├── .gitignore ├── README.md ├── images ├── Avail Arch.excalidraw ├── Avail Arch.svg ├── Light Client P2P Network.jpg └── Nomad Avail Message Flow.svg └── reference document ├── ACM-Reference-Format.bst ├── Avail Reference Paper v2 17 Sept 2024.pdf ├── Avail Reference Paper v2.1 6 Nov 2024.pdf ├── DA-KC-Data.drawio ├── DA-KC-Data.png ├── DA_references.bib ├── Data Availability - Reference Document.pdf ├── Data Availability - Reference Document.tex ├── README.md └── acmart.cls /.gitignore: -------------------------------------------------------------------------------- 1 | reference document/Data Availability - Reference Document.log 2 | reference document/Data Availability - Reference Document.synctex.gz 3 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 |

2 |

Avail

3 |

Documentation & Links for the Avail blockchain

4 |

5 | 6 |
7 | 8 | Avail is a Web3 infrastructure layer that allows modular execution layers to scale and interoperate in a trust minimized way. Below, you can find a list of some of the relevant GitHub repositories. 9 | 10 | | Name (with link) | Description | 11 | |:----------------------:|:---------------------------------------------------------------------------------------:| 12 | | [Reference Document](https://github.com/availproject/data-availability/blob/93c547ce4efce3e992b573179a8d22b3657fdcee/reference%20document/Avail%20Reference%20Paper%20v2.1%206%20Nov%202024.pdf) | Document containing the overall rationale, design decisions and theoretical backgrounds | 13 | | [Avail Node](https://github.com/availproject/avail) | Avail node implementation repo. Built using Substrate. | 14 | | [Light Client](https://github.com/availproject/avail-light) | Light client designed to check data availability proofs on Avail. | 15 | | [Explorer](https://github.com/availproject/avail-apps) | Avail explorer implementation repo. Built using Polkadot apps. | 16 | | [Bridge UI](https://github.com/availproject/bridge-ui) | Repository for the official Avail <-> ETH bridge UI | 17 | | [Documentation](https://availproject.github.io/) | Avail documentation hub. | 18 | | [Tests](https://github.com/availproject/avail-test) | End to end tests for Avail. | 19 | 20 | Suggestions and feedback welcome. 21 | 22 | ## Avail Architecture 23 | 24 | There are two main components in the Avail network: 25 | 26 | - [Avail Node](https://github.com/availproject/avail): This forms the blockchain layer of Avail. It is built using Substrate, with modifications to specialize it for data availability. Apart from basic blockchain operations like balance transfer, validator staking, slashing and governance, it also contains methods for applications to submit data blobs. This network is secured by the GRANDPA+BABE consensus engine, under the assumption that at least 2/3 of the validator set is honest. 27 | - [Avail Light Client](https://github.com/availproject/avail-light): The light clients (LC) form an overlay P2P network. Individually, all LCs subscribe to (finalized) headers of the chain. It performs Data Availability Sampling (DAS) to gain high confidence of DA. The LCs also host the sampled data on the P2P so that together the P2P network can have the entire data in a highly available manner. 28 | 29 | ![Avail Architecture](./images/Light%20Client%20P2P%20Network.jpg) 30 | 31 | ## Bridge between Avail and Ethereum using VectorX 32 | 33 | The Avail team has partnered with [Succinct labs](https://succinct.xyz/) to develop a trust-minimized bridge between Avail DA and Ethereum. VectorX enables efficient and trust-minimized bridging of arbitrary messages between Avail DA and Ethereum, which enables use cases like token bridging. You can use the [bridge](https://docs.availproject.org/docs/end-user-guide/vectorx) through the [official UI](bridge.availproject.org). 34 | 35 | -------------------------------------------------------------------------------- /images/Avail Arch.svg: -------------------------------------------------------------------------------- 1 | -------------------------------------------------------------------------------- /images/Light Client P2P Network.jpg: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/availproject/data-availability/1fa5e8b1260344b137b17a3dfa1e493a14b5888a/images/Light Client P2P Network.jpg -------------------------------------------------------------------------------- /reference document/ACM-Reference-Format.bst: -------------------------------------------------------------------------------- 1 | %%% -*-BibTeX-*- 2 | %%% ==================================================================== 3 | %%% @BibTeX-style-file{ 4 | %%% author = "Nelson H. F. Beebe, Boris Veytsman and Gerald Murray", 5 | %%% version = "2.1", 6 | %%% date = "14 June 2017", 7 | %%% filename = "ACM-Reference-Format.bst", 8 | %%% email = "borisv@lk.net, boris@varphi.com", 9 | %%% codetable = "ISO/ASCII", 10 | %%% keywords = "ACM Transactions bibliography style; BibTeX", 11 | %%% license = "public domain", 12 | %%% supported = "yes", 13 | %%% abstract = "", 14 | %%% } 15 | %%% ==================================================================== 16 | 17 | %%% Revision history: see source in git 18 | 19 | ENTRY 20 | { address 21 | advisor 22 | archiveprefix 23 | author 24 | booktitle 25 | chapter 26 | city 27 | date 28 | edition 29 | editor 30 | eprint 31 | eprinttype 32 | eprintclass 33 | howpublished 34 | institution 35 | journal 36 | key 37 | location 38 | month 39 | note 40 | number 41 | organization 42 | pages 43 | primaryclass 44 | publisher 45 | school 46 | series 47 | title 48 | type 49 | volume 50 | year 51 | % New keys recognized 52 | issue % UTAH: used in, e.g., ACM SIGSAM Bulletin and ACM Communications in Computer Algebra 53 | articleno 54 | eid 55 | day % UTAH: needed for newspapers, weeklies, bi-weeklies 56 | doi % UTAH 57 | url % UTAH 58 | bookpages % UTAH 59 | numpages 60 | lastaccessed % UTAH: used only for @Misc{...} 61 | coden % UTAH 62 | isbn % UTAH 63 | isbn-13 % UTAH 64 | issn % UTAH 65 | lccn % UTAH 66 | } 67 | {} 68 | { label.year extra.label sort.year sort.label basic.label.year} 69 | 70 | INTEGERS { output.state before.all mid.sentence after.sentence after.block } 71 | 72 | INTEGERS { show-isbn-10-and-13 } % initialized below in begin.bib 73 | 74 | INTEGERS { nameptr namesleft numnames } 75 | 76 | INTEGERS { multiresult } 77 | 78 | INTEGERS { len } 79 | 80 | INTEGERS { last.extra.num } 81 | 82 | STRINGS { s t t.org u } 83 | 84 | STRINGS { last.label next.extra } 85 | 86 | STRINGS { p1 p2 p3 page.count } 87 | 88 | 89 | FUNCTION { not } 90 | { 91 | { #0 } 92 | { #1 } 93 | if$ 94 | } 95 | 96 | FUNCTION { and } 97 | { 98 | 'skip$ 99 | { pop$ #0 } 100 | if$ 101 | } 102 | 103 | FUNCTION { or } 104 | { 105 | { pop$ #1 } 106 | 'skip$ 107 | if$ 108 | } 109 | 110 | 111 | FUNCTION { dump.stack.1 } 112 | { 113 | duplicate$ "STACK[top] = [" swap$ * "]" * warning$ 114 | } 115 | 116 | FUNCTION { dump.stack.2 } 117 | { 118 | duplicate$ "STACK[top ] = [" swap$ * "]" * warning$ 119 | swap$ 120 | duplicate$ "STACK[top-1] = [" swap$ * "]" * warning$ 121 | swap$ 122 | } 123 | 124 | FUNCTION { empty.or.unknown } 125 | { 126 | %% Examine the top stack entry, and push 1 if it is empty, or 127 | %% consists only of whitespace, or is a string beginning with two 128 | %% queries (??), and otherwise, push 0. 129 | %% 130 | %% This function provides a replacement for empty$, with the 131 | %% convenient feature that unknown values marked by two leading 132 | %% queries are treated the same as missing values, and thus, do not 133 | %% appear in the output .bbl file, and yet, their presence in .bib 134 | %% file(s) serves to mark values which are temporarily missing, but 135 | %% are expected to be filled in eventually once more data is 136 | %% obtained. The TeX User Group and BibNet bibliography archives 137 | %% make extensive use of this practice. 138 | %% 139 | %% An empty string cannot serve the same purpose, because just as in 140 | %% statistics data processing, an unknown value is not the same as an 141 | %% empty value. 142 | %% 143 | %% At entry: stack = ... top:[string] 144 | %% At exit: stack = ... top:[0 or 1] 145 | 146 | duplicate$ empty$ 147 | { pop$ #1 } 148 | { #1 #2 substring$ "??" = } 149 | if$ 150 | } 151 | 152 | FUNCTION { writeln } 153 | { 154 | %% In BibTeX style files, the sequences 155 | %% 156 | %% ... "one" "two" output 157 | %% ... "one" "two" output.xxx 158 | %% 159 | %% ship "one" to the output file, possibly following by punctuation, 160 | %% leaving the stack with 161 | %% 162 | %% ... "two" 163 | %% 164 | %% There is thus a one-string lag in output processing that must be 165 | %% carefully handled to avoid duplicating a string in the output 166 | %% file. Unless otherwise noted, all output.xxx functions leave 167 | %% just one new string on the stack, and that model should be born 168 | %% in mind when reading or writing function code. 169 | %% 170 | %% BibTeX's asynchronous buffering of output from strings from the 171 | %% stack is confusing because newline$ bypasses the buffer. It 172 | %% would have been so much easier for newline to be a character 173 | %% rather than a state of the output-in-progress. 174 | %% 175 | %% The documentation in btxhak.dvi is WRONG: it says 176 | %% 177 | %% newline$ Writes onto the bbl file what's accumulated in the 178 | %% output buffer. It writes a blank line if and only 179 | %% if the output buffer is empty. Since write$ does 180 | %% reasonable line breaking, you should use this 181 | %% function only when you want a blank line or an 182 | %% explicit line break. 183 | %% 184 | %% write$ Pops the top (string) literal and writes it on the 185 | %% output buffer (which will result in stuff being 186 | %% written onto the bbl file when the buffer fills 187 | %% up). 188 | %% 189 | %% Examination of the BibTeX source code shows that write$ does 190 | %% indeed behave as claimed, but newline$ sends a newline character 191 | %% directly to the output file, leaving the stack unchanged. The 192 | %% first line "Writes onto ... buffer." is therefore wrong. 193 | %% 194 | %% The original BibTeX style files almost always use "write$ newline$" 195 | %% in that order, so it makes sense to hide that pair in a private 196 | %% function like this one, named after a statement in Pascal, 197 | %% the programming language embedded in the BibTeX Web program. 198 | 199 | write$ % output top-of-stack string 200 | newline$ % immediate write of newline (not via stack) 201 | } 202 | 203 | FUNCTION { init.state.consts } 204 | { 205 | #0 'before.all := 206 | #1 'mid.sentence := 207 | #2 'after.sentence := 208 | #3 'after.block := 209 | } 210 | 211 | FUNCTION { output.nonnull } 212 | { % Stack in: ... R S T Stack out: ... R T File out: S 213 | 's := 214 | output.state mid.sentence = 215 | { 216 | ", " * write$ 217 | } 218 | { 219 | output.state after.block = 220 | { 221 | add.period$ writeln 222 | "\newblock " write$ 223 | } 224 | { 225 | output.state before.all = 226 | { 227 | write$ 228 | } 229 | { 230 | add.period$ " " * write$ 231 | } 232 | if$ 233 | } 234 | if$ 235 | mid.sentence 'output.state := 236 | } 237 | if$ 238 | s 239 | } 240 | 241 | FUNCTION { output.nonnull.dot.space } 242 | { % Stack in: ... R S T Stack out: ... R T File out: S 243 | 's := 244 | output.state mid.sentence = % { ". " * write$ } 245 | { 246 | ". " * write$ 247 | } 248 | { 249 | output.state after.block = 250 | { 251 | add.period$ writeln "\newblock " write$ 252 | } 253 | { 254 | output.state before.all = 255 | { 256 | write$ 257 | } 258 | { 259 | add.period$ " " * write$ 260 | } 261 | if$ 262 | } 263 | if$ 264 | mid.sentence 'output.state := 265 | } 266 | if$ 267 | s 268 | } 269 | 270 | FUNCTION { output.nonnull.remove } 271 | { % Stack in: ... R S T Stack out: ... R T File out: S 272 | 's := 273 | output.state mid.sentence = 274 | { 275 | " " * write$ 276 | } 277 | { 278 | output.state after.block = 279 | { 280 | add.period$ writeln "\newblock " write$ 281 | } 282 | { 283 | output.state before.all = 284 | { 285 | write$ 286 | } 287 | { 288 | add.period$ " " * write$ 289 | } 290 | if$ 291 | } 292 | if$ 293 | mid.sentence 'output.state := 294 | } 295 | if$ 296 | s 297 | } 298 | 299 | FUNCTION { output.nonnull.removenospace } 300 | { % Stack in: ... R S T Stack out: ... R T File out: S 301 | 's := 302 | output.state mid.sentence = 303 | { 304 | "" * write$ 305 | } 306 | { 307 | output.state after.block = 308 | { 309 | add.period$ writeln "\newblock " write$ 310 | } 311 | { 312 | output.state before.all = 313 | { 314 | write$ 315 | } 316 | { 317 | add.period$ " " * write$ 318 | } 319 | if$ 320 | } 321 | if$ 322 | mid.sentence 'output.state := 323 | } 324 | if$ 325 | s 326 | } 327 | 328 | FUNCTION { output } 329 | { % discard top token if empty, else like output.nonnull 330 | duplicate$ empty.or.unknown 331 | 'pop$ 332 | 'output.nonnull 333 | if$ 334 | } 335 | 336 | FUNCTION { output.dot.space } 337 | { % discard top token if empty, else like output.nonnull.dot.space 338 | duplicate$ empty.or.unknown 339 | 'pop$ 340 | 'output.nonnull.dot.space 341 | if$ 342 | } 343 | 344 | FUNCTION { output.removenospace } 345 | { % discard top token if empty, else like output.nonnull.removenospace 346 | duplicate$ empty.or.unknown 347 | 'pop$ 348 | 'output.nonnull.removenospace 349 | if$ 350 | } 351 | 352 | FUNCTION { output.check } 353 | { % like output, but warn if key name on top-of-stack is not set 354 | 't := 355 | duplicate$ empty.or.unknown 356 | { pop$ "empty " t * " in " * cite$ * warning$ } 357 | 'output.nonnull 358 | if$ 359 | } 360 | 361 | FUNCTION { bibinfo.output.check } 362 | { % like output.check, adding bibinfo field 363 | 't := 364 | duplicate$ empty.or.unknown 365 | { pop$ "empty " t * " in " * cite$ * warning$ } 366 | { "\bibinfo{" t "}{" * * swap$ * "}" * 367 | output.nonnull } 368 | if$ 369 | } 370 | 371 | FUNCTION { output.check.dot.space } 372 | { % like output.dot.space, but warn if key name on top-of-stack is not set 373 | 't := 374 | duplicate$ empty.or.unknown 375 | { pop$ "empty " t * " in " * cite$ * warning$ } 376 | 'output.nonnull.dot.space 377 | if$ 378 | } 379 | 380 | FUNCTION { fin.block } 381 | { % functionally, but not logically, identical to fin.entry 382 | add.period$ 383 | writeln 384 | } 385 | 386 | FUNCTION { fin.entry } 387 | { 388 | add.period$ 389 | writeln 390 | } 391 | 392 | FUNCTION { new.sentence } 393 | { % update sentence state, with neither output nor stack change 394 | output.state after.block = 395 | 'skip$ 396 | { 397 | output.state before.all = 398 | 'skip$ 399 | { after.sentence 'output.state := } 400 | if$ 401 | } 402 | if$ 403 | } 404 | 405 | FUNCTION { fin.sentence } 406 | { 407 | add.period$ 408 | write$ 409 | new.sentence 410 | "" 411 | } 412 | 413 | FUNCTION { new.block } 414 | { 415 | output.state before.all = 416 | 'skip$ 417 | { after.block 'output.state := } 418 | if$ 419 | } 420 | 421 | FUNCTION { output.coden } % UTAH 422 | { % output non-empty CODEN as one-line sentence (stack untouched) 423 | coden empty.or.unknown 424 | { } 425 | { "\showCODEN{" coden * "}" * writeln } 426 | if$ 427 | } 428 | 429 | % 430 | % Sometimes articleno starts with the word 'Article' or 'Paper. 431 | % (this is a bug of acmdl, sigh) 432 | % We strip them. We assume eid or articleno is already on stack 433 | % 434 | 435 | FUNCTION { strip.articleno.or.eid } 436 | { 437 | 't := 438 | t #1 #7 substring$ "Article" = 439 | {t #8 t text.length$ substring$ 't :=} 440 | { } 441 | if$ 442 | t #1 #7 substring$ "article" = 443 | {t #8 t text.length$ substring$ 't :=} 444 | { } 445 | if$ 446 | t #1 #5 substring$ "Paper" = 447 | {t #6 t text.length$ substring$ 't :=} 448 | { } 449 | if$ 450 | t #1 #5 substring$ "paper" = 451 | {t #6 t text.length$ substring$ 't :=} 452 | { } 453 | if$ 454 | % Strip any left trailing space or ~ 455 | t #1 #1 substring$ " " = 456 | {t #2 t text.length$ substring$ 't :=} 457 | { } 458 | if$ 459 | t #1 #1 substring$ "~" = 460 | {t #2 t text.length$ substring$ 't :=} 461 | { } 462 | if$ 463 | t 464 | } 465 | 466 | 467 | FUNCTION { format.articleno } 468 | { 469 | articleno empty.or.unknown not eid empty.or.unknown not and 470 | { "Both articleno and eid are defined for " cite$ * warning$ } 471 | 'skip$ 472 | if$ 473 | articleno empty.or.unknown eid empty.or.unknown and 474 | { "" } 475 | { 476 | numpages empty.or.unknown 477 | { "articleno or eid field, but no numpages field, in " 478 | cite$ * warning$ } 479 | { } 480 | if$ 481 | eid empty.or.unknown 482 | { "Article \bibinfo{articleno}{" articleno strip.articleno.or.eid * "}" * } 483 | { "Article \bibinfo{articleno}{" eid strip.articleno.or.eid * "}" * } 484 | if$ 485 | } 486 | if$ 487 | } 488 | 489 | FUNCTION { format.year } 490 | { % push year string or "[n.\,d.]" onto output stack 491 | %% Because year is a mandatory field, we always force SOMETHING 492 | %% to be output 493 | "\bibinfo{year}{" 494 | year empty.or.unknown 495 | { "[n.\,d.]" } 496 | { year } 497 | if$ 498 | * "}" * 499 | } 500 | 501 | FUNCTION { format.day.month } 502 | { % push "day month " or "month " or "" onto output stack 503 | day empty.or.unknown 504 | { 505 | month empty.or.unknown 506 | { "" } 507 | { "\bibinfo{date}{" month * "} " *} 508 | if$ 509 | } 510 | { 511 | month empty.or.unknown 512 | { "" } 513 | { "\bibinfo{date}{" day * " " * month * "} " *} 514 | if$ 515 | } 516 | if$ 517 | } 518 | 519 | FUNCTION { format.day.month.year } % UTAH 520 | { % if month is empty, push "" else push "(MON.)" or "(DD MON.)" 521 | % Needed for frequent periodicals: 2008. ... New York Times C-1, C-2, C-17 (23 Oct.) 522 | % acm-*.bst addition: prefix parenthesized date string with 523 | % ", Article nnn " 524 | articleno empty.or.unknown eid empty.or.unknown and 525 | { "" } 526 | { output.state after.block = 527 | {", " format.articleno * } 528 | { format.articleno } 529 | if$ 530 | } 531 | if$ 532 | " (" * format.day.month * format.year * ")" * 533 | } 534 | 535 | FUNCTION { output.day.month.year } % UTAH 536 | { % if month is empty value, do nothing; else output stack top and 537 | % leave with new top string "(MON.)" or "(DD MON.)" 538 | % Needed for frequent periodicals: 2008. ... New York Times C-1, C-2, C-17 (23 Oct.) 539 | format.day.month.year 540 | output.nonnull.remove 541 | } 542 | 543 | FUNCTION { strip.doi } % UTAH 544 | { % Strip any Web address prefix to recover the bare DOI, leaving the 545 | % result on the output stack, as recommended by CrossRef DOI 546 | % documentation. 547 | % For example, reduce "http://doi.acm.org/10.1145/1534530.1534545" to 548 | % "10.1145/1534530.1534545". A suitable URL is later typeset and 549 | % displayed as the LAST item in the reference list entry. Publisher Web 550 | % sites wrap this with a suitable link to a real URL to resolve the DOI, 551 | % and the master https://doi.org/ address is preferred, since publisher- 552 | % specific URLs can disappear in response to economic events. All 553 | % journals are encouraged by the DOI authorities to use that typeset 554 | % format and link procedures for uniformity across all publications that 555 | % include DOIs in reference lists. 556 | % The numeric prefix is guaranteed to start with "10.", so we use 557 | % that as a test. 558 | % 2017-02-04 Added stripping of https:// (Boris) 559 | doi #1 #3 substring$ "10." = 560 | { doi } 561 | { 562 | doi 't := % get modifiable copy of DOI 563 | 564 | % Change https:// to http:// to strip both prefixes (BV) 565 | 566 | t #1 #8 substring$ "https://" = 567 | { "http://" t #9 t text.length$ #8 - substring$ * 't := } 568 | { } 569 | if$ 570 | 571 | t #1 #7 substring$ "http://" = 572 | { 573 | t #8 t text.length$ #7 - substring$ 't := 574 | 575 | "INTERNAL STYLE-FILE ERROR" 's := 576 | 577 | % search for next "/" and assign its suffix to s 578 | 579 | { t text.length$ } 580 | { 581 | t #1 #1 substring$ "/" = 582 | { 583 | % save rest of string as true DOI (should be 10.xxxx/yyyy) 584 | t #2 t text.length$ #1 - substring$ 's := 585 | "" 't := % empty string t terminates the loop 586 | } 587 | { 588 | % discard first character and continue loop: t <= substring(t,2,last) 589 | t #2 t text.length$ #1 - substring$ 't := 590 | } 591 | if$ 592 | } 593 | while$ 594 | 595 | % check for valid DOI (should be 10.xxxx/yyyy) 596 | s #1 #3 substring$ "10." = 597 | { } 598 | { "unrecognized DOI substring " s * " in DOI value [" * doi * "]" * warning$ } 599 | if$ 600 | 601 | s % push the stripped DOI on the output stack 602 | 603 | } 604 | { 605 | "unrecognized DOI value [" doi * "]" * warning$ 606 | doi % push the unrecognized original DOI on the output stack 607 | } 608 | if$ 609 | } 610 | if$ 611 | } 612 | 613 | % 614 | % Change by BV: added standard prefix to URL 615 | % 616 | FUNCTION { output.doi } % UTAH 617 | { % output non-empty DOI as one-line sentence (stack untouched) 618 | doi empty.or.unknown 619 | { } 620 | { 621 | %% Use \urldef here for the same reason it is used in output.url, 622 | %% see output.url for further discussion. 623 | "\urldef\tempurl%" writeln 624 | "\url{https://doi.org/" strip.doi * "}" * writeln 625 | "\showDOI{\tempurl}" writeln 626 | } 627 | if$ 628 | } 629 | 630 | FUNCTION { output.isbn } % UTAH 631 | { % output non-empty ISBN-10 and/or ISBN-13 as one-line sentences (stack untouched) 632 | show-isbn-10-and-13 633 | { 634 | %% show both 10- and 13-digit ISBNs 635 | isbn empty.or.unknown 636 | { } 637 | { 638 | "\showISBNx{" isbn * "}" * writeln 639 | } 640 | if$ 641 | isbn-13 empty.or.unknown 642 | { } 643 | { 644 | "\showISBNxiii{" isbn-13 * "}" * writeln 645 | } 646 | if$ 647 | } 648 | { 649 | %% show 10-digit ISBNs only if 13-digit ISBNs not available 650 | isbn-13 empty.or.unknown 651 | { 652 | isbn empty.or.unknown 653 | { } 654 | { 655 | "\showISBNx{" isbn * "}" * writeln 656 | } 657 | if$ 658 | } 659 | { 660 | "\showISBNxiii{" isbn-13 * "}" * writeln 661 | } 662 | if$ 663 | } 664 | if$ 665 | } 666 | 667 | FUNCTION { output.issn } % UTAH 668 | { % output non-empty ISSN as one-line sentence (stack untouched) 669 | issn empty.or.unknown 670 | { } 671 | { "\showISSN{" issn * "}" * writeln } 672 | if$ 673 | } 674 | 675 | FUNCTION { output.issue } 676 | { % output non-empty issue number as a one-line sentence (stack untouched) 677 | issue empty.or.unknown 678 | { } 679 | { "Issue " issue * "." * writeln } 680 | if$ 681 | } 682 | 683 | FUNCTION { output.lccn } % UTAH 684 | { % return with stack untouched 685 | lccn empty.or.unknown 686 | { } 687 | { "\showLCCN{" lccn * "}" * writeln } 688 | if$ 689 | } 690 | 691 | FUNCTION { output.note } % UTAH 692 | { % return with stack empty 693 | note empty.or.unknown 694 | { } 695 | { "\shownote{" note add.period$ * "}" * writeln } 696 | if$ 697 | } 698 | 699 | FUNCTION { output.note.check } % UTAH 700 | { % return with stack empty 701 | note empty.or.unknown 702 | { "empty note in " cite$ * warning$ } 703 | { "\shownote{" note add.period$ * "}" * writeln } 704 | if$ 705 | } 706 | 707 | FUNCTION { output.eprint } % 708 | { % return with stack empty 709 | eprint empty.or.unknown 710 | { } 711 | { "\showeprint" 712 | archiveprefix empty.or.unknown 713 | { eprinttype empty.or.unknown 714 | { } 715 | { "[" eprinttype "]" * * * } 716 | if$ 717 | } 718 | { "[" archiveprefix "l" change.case$ "]" * * * } 719 | if$ 720 | "{" eprint "}" * * * 721 | primaryclass empty.or.unknown 722 | { eprintclass empty.or.unknown 723 | { } 724 | { "~[" eprintclass "]" * * * } 725 | if$ 726 | } 727 | { "~[" primaryclass "]" * * * } 728 | if$ 729 | writeln 730 | } 731 | if$ 732 | } 733 | 734 | 735 | % 736 | % Changes by BV 2011/04/15. Do not output 737 | % url if doi is defined 738 | % 739 | FUNCTION { output.url } % UTAH 740 | { % return with stack untouched 741 | % output URL and associated lastaccessed fields 742 | doi empty.or.unknown 743 | { 744 | url empty.or.unknown 745 | { } 746 | { 747 | %% Use \urldef, outside \showURL, so that %nn, #, etc in URLs work 748 | %% correctly. Put the actual URL on its own line to reduce the 749 | %% likelihood of BibTeX's nasty line wrapping after column 79. 750 | %% \url{} can undo this, but if that doesn't work for some reason 751 | %% the .bbl file would have to be repaired manually. 752 | "\urldef\tempurl%" writeln 753 | "\url{" url * "}" * writeln 754 | 755 | "\showURL{%" writeln 756 | lastaccessed empty.or.unknown 757 | { "" } 758 | { "Retrieved " lastaccessed * " from " * } 759 | if$ 760 | "\tempurl}" * writeln 761 | } 762 | if$ 763 | } 764 | { } 765 | if$ 766 | } 767 | 768 | FUNCTION { output.year.check } 769 | { % warn if year empty, output top string and leave " YEAR" on stack in mid-sentence 770 | year empty.or.unknown 771 | { "empty year in " cite$ * warning$ 772 | write$ 773 | " \bibinfo{year}{[n.d.]}" 774 | "\natexlab{" extra.label * "}" * * 775 | mid.sentence 'output.state := 776 | } 777 | { write$ 778 | " \bibinfo{year}{" year * "}" * 779 | "\natexlab{" extra.label * "}" * * 780 | mid.sentence 'output.state := 781 | } 782 | if$ 783 | } 784 | 785 | 786 | FUNCTION { le } 787 | { 788 | %% test whether first number is less than or equal to second number 789 | %% stack in: n1 n2 790 | %% stack out: if n1 <= n2 then 1 else 0 791 | 792 | %% "DEBUG: le " cite$ * warning$ 793 | > { #0 } { #1 } if$ 794 | } 795 | 796 | FUNCTION { ge } 797 | { 798 | %% test whether first number is greater than or equal to second number 799 | %% stack in: n1 n2 800 | %% stack out: if n1 >= n2 then 1 else 0 801 | 802 | %% "DEBUG: ge " cite$ * warning$ 803 | < { #0 } { #1 } if$ 804 | } 805 | 806 | FUNCTION { is.leading.digit } 807 | { 808 | %% test whether first character of string is a digit 809 | %% stack in: string 810 | %% stack out: if first-char-is-digit then 1 else 0 811 | 812 | #1 #1 substring$ % replace string by string[1:1] 813 | duplicate$ % string[1:1] string[1:1] 814 | chr.to.int$ 815 | "0" chr.to.int$ swap$ le % "0" <= string[1:1] --> 0-or-1 816 | swap$ % 0-or-1 string[1:1] 817 | chr.to.int$ 818 | "9" chr.to.int$ le % string[1:1} <= "9" --> 0-or-1 819 | and 820 | } 821 | 822 | FUNCTION { skip.digits } 823 | { 824 | %% skip over leading digits in string 825 | %% stack in: string 826 | %% stack out: rest-of-string leading-digits 827 | 828 | %% "DEBUG: enter skip.digits " cite$ * warning$ 829 | 830 | %% dump.stack.1 831 | 832 | duplicate$ 833 | 't := 834 | 't.org := 835 | "" 'u := 836 | 837 | { t text.length$ } 838 | { 839 | %% "=================DEBUG: skip.digits t = [" t * "]" * warning$ 840 | t is.leading.digit 841 | { t #2 t text.length$ #1 - substring$ } 842 | { 843 | t 'u := 844 | "" 845 | } 846 | if$ 847 | 't := 848 | } 849 | while$ 850 | 851 | u % rest of string 852 | t.org #1 t.org text.length$ u text.length$ - substring$ % leading digits 853 | 854 | %% "DEBUG: t.org = [" t.org * "]" * warning$ 855 | %% "DEBUG: u = [" u * "]" * warning$ 856 | 857 | %% dump.stack.2 858 | 859 | %% "DEBUG: leave skip.digits " cite$ * warning$ 860 | } 861 | 862 | FUNCTION { skip.nondigits } 863 | { 864 | %% skip over leading nondigits in string 865 | %% stack in: string 866 | %% stack out: rest-of-string 867 | 868 | %% "DEBUG: enter skip.nondigits " cite$ * warning$ 869 | 870 | 't := 871 | "" 'u := 872 | 873 | { t text.length$ } 874 | { 875 | %% "=================DEBUG: skip.nondigits t = [" t * "]" * warning$ 876 | t is.leading.digit 877 | { 878 | t 'u := 879 | "" 880 | } 881 | { t #2 t text.length$ #1 - substring$ } 882 | if$ 883 | 't := 884 | } 885 | while$ 886 | 887 | u % rest of string 888 | 889 | %% dump.stack.1 890 | %% "DEBUG: leave skip.nondigits " cite$ * warning$ 891 | } 892 | 893 | FUNCTION { parse.next.number } 894 | { 895 | %% stack in: string 896 | %% stack out: rest-of-string next-numeric-part-of-string 897 | %% Example: 898 | %% stack in: "123:1--123:59" 899 | %% stack out: ":1--123:59" "123" 900 | 901 | 's := 902 | s skip.nondigits 's := 903 | s skip.digits 904 | } 905 | 906 | FUNCTION { reduce.pages.to.page.count } 907 | { 908 | %% Stack in: arbitrary-and-unused 909 | %% Stack out: unchanged 910 | %% 911 | %% For the new-style pagination with article number and numpages or 912 | %% pages, we expect to have BibTeX entries containing something like 913 | %% articleno = "17", 914 | %% pages = "1--23", 915 | %% with output "Article 17, 23 pages", 916 | %% or 917 | %% articleno = "17", 918 | %% numpages = "23", 919 | %% with output "Article 17, 23 pages", 920 | %% or 921 | %% articleno = "17", 922 | %% pages = "17:1--17:23", 923 | %% with output "Article 17, 23 pages", 924 | %% 925 | %% If articleno is missing or empty, then we should output "1--23", 926 | %% "23" (with a warning of a missing articleno), or "17:1--17:23", 927 | %% respectively. 928 | 929 | %% "DEBUG: enter reduce.pages.to.page.count " cite$ * warning$ 930 | 931 | %% "DEBUG: pages = [" pages * "]" * warning$ 932 | 933 | pages 934 | parse.next.number 'p1 := 935 | parse.next.number 'p2 := 936 | parse.next.number 'p3 := 937 | parse.next.number 'page.count := 938 | 939 | duplicate$ 940 | empty.or.unknown 941 | { } 942 | { 943 | duplicate$ "unexpected trailing garbage [" swap$ * 944 | "] after n:p1--n:p2 in pages = [" * 945 | pages * 946 | "] in " * 947 | cite$ * 948 | warning$ 949 | } 950 | if$ 951 | 952 | pop$ 953 | 954 | %% "DEBUG: reduce.pages.to.page.count: " 955 | %% " p1 = " p1 * * 956 | %% " p2 = " p2 * * 957 | %% " p3 = " p3 * * 958 | %% " p4 = " page.count * * 959 | %% " in " cite$ * * warning$ 960 | 961 | p1 p3 = p2 "1" = and numpages empty.or.unknown and 962 | { "INFO: reduced pages = [" pages * "] to numpages = [" * page.count * "]" * warning$ } 963 | { 964 | numpages empty.or.unknown 965 | { pages } 966 | { numpages } 967 | if$ 968 | 'page.count := 969 | } 970 | if$ 971 | 972 | p1 "1" = p3 empty.or.unknown and numpages empty.or.unknown and 973 | { 974 | p2 'page.count := 975 | "INFO: reduced pages = [" pages * "] to numpages = [" * page.count * "]" * warning$ 976 | } 977 | { 978 | numpages empty.or.unknown 979 | { pages } 980 | { numpages } 981 | if$ 982 | 'page.count := 983 | } 984 | if$ 985 | 986 | %% "DEBUG: leave reduce.pages.to.page.count " cite$ * warning$ 987 | } 988 | 989 | FUNCTION { new.block.checkb } 990 | { % issue a new.block only if at least one of top two stack strings is not empty 991 | empty.or.unknown 992 | swap$ empty.or.unknown 993 | and 994 | 'skip$ 995 | 'new.block 996 | if$ 997 | } 998 | 999 | FUNCTION { field.or.null } 1000 | { % convert empty value to null string, else return value 1001 | duplicate$ empty.or.unknown 1002 | { pop$ "" } 1003 | 'skip$ 1004 | if$ 1005 | } 1006 | 1007 | 1008 | 1009 | FUNCTION { emphasize } 1010 | { % emphasize a non-empty top string on the stack 1011 | duplicate$ empty.or.unknown 1012 | { pop$ "" } 1013 | { "\emph{" swap$ * "}" * } 1014 | if$ 1015 | } 1016 | 1017 | FUNCTION { comma } 1018 | { % convert empty string to null string, or brace string and add trailing comma 1019 | duplicate$ empty.or.unknown 1020 | { pop$ "" } 1021 | { "{" swap$ * "}," * } 1022 | if$ 1023 | } 1024 | 1025 | FUNCTION { format.names } 1026 | { 1027 | % Format bibliographical entries with the first author last name first, 1028 | % and subsequent authors with initials followed by last name. 1029 | % All names are formatted in this routine. 1030 | 1031 | 's := 1032 | #1 'nameptr := % nameptr = 1; 1033 | s num.names$ 'numnames := % numnames = num.name$(s); 1034 | numnames 'namesleft := 1035 | { namesleft #0 > } 1036 | { nameptr #1 = 1037 | %NO: BAD ORDER: {"{" s nameptr "{ff~}{ll}{, jj}{, vv}" format.name$ * "}" * 't := } 1038 | %NO: BAD ORDER: {"{" s nameptr "{ff~}{ll}{, jj}{, vv}" format.name$ * "}" * 't := } 1039 | {"\bibinfo{person}{" s nameptr "{ff }{vv }{ll}{, jj}" format.name$ * "}" * 't := } 1040 | {"\bibinfo{person}{" s nameptr "{ff }{vv }{ll}{, jj}" format.name$ * "}" * 't := } 1041 | if$ 1042 | nameptr #1 > 1043 | { 1044 | namesleft #1 > 1045 | { ", " * t * } 1046 | { 1047 | numnames #2 > 1048 | { "," * } 1049 | 'skip$ 1050 | if$ 1051 | t "\bibinfo{person}{others}" = 1052 | { " {et~al\mbox{.}}" * } % jrh: avoid spacing problems 1053 | { " {and} " * t * } % from Chicago Manual of Style 1054 | if$ 1055 | } 1056 | if$ 1057 | } 1058 | 't 1059 | if$ 1060 | nameptr #1 + 'nameptr := % nameptr += 1; 1061 | namesleft #1 - 'namesleft := % namesleft =- 1; 1062 | } 1063 | while$ 1064 | } 1065 | 1066 | FUNCTION { my.full.label } 1067 | { 1068 | 's := 1069 | #1 'nameptr := % nameptr = 1; 1070 | s num.names$ 'numnames := % numnames = num.name$(s); 1071 | numnames 'namesleft := 1072 | { namesleft #0 > } 1073 | 1074 | { s nameptr "{vv~}{ll}" format.name$ 't := % get the next name 1075 | nameptr #1 > 1076 | { 1077 | namesleft #1 > 1078 | { ", " * t * } 1079 | { 1080 | numnames #2 > 1081 | { "," * } 1082 | 'skip$ 1083 | if$ 1084 | t "others" = 1085 | { " et~al\mbox{.}" * } % jrh: avoid spacing problems 1086 | { " and " * t * } % from Chicago Manual of Style 1087 | if$ 1088 | } 1089 | if$ 1090 | } 1091 | 't 1092 | if$ 1093 | nameptr #1 + 'nameptr := % nameptr += 1; 1094 | namesleft #1 - 'namesleft := % namesleft =- 1; 1095 | } 1096 | while$ 1097 | 1098 | } 1099 | 1100 | FUNCTION { format.names.fml } 1101 | { 1102 | % Format names in "familiar" format, with first initial followed by 1103 | % last name. Like format.names, ALL names are formatted. 1104 | % jtb: The names are NOT put in small caps 1105 | 1106 | 's := 1107 | #1 'nameptr := % nameptr = 1; 1108 | s num.names$ 'numnames := % numnames = num.name$(s); 1109 | numnames 'namesleft := 1110 | { namesleft #0 > } 1111 | 1112 | { 1113 | "\bibinfo{person}{" s nameptr "{ff~}{vv~}{ll}{, jj}" format.name$ * "}" * 't := 1114 | 1115 | nameptr #1 > 1116 | { 1117 | namesleft #1 > 1118 | { ", " * t * } 1119 | { 1120 | numnames #2 > 1121 | { "," * } 1122 | 'skip$ 1123 | if$ 1124 | t "\bibinfo{person}{others}" = 1125 | { " {et~al\mbox{.}}" * } 1126 | { " {and} " * t * } 1127 | if$ 1128 | } 1129 | if$ 1130 | } 1131 | 't 1132 | if$ 1133 | nameptr #1 + 'nameptr := % nameptr += 1; 1134 | namesleft #1 - 'namesleft := % namesleft =- 1; 1135 | } 1136 | while$ 1137 | } 1138 | 1139 | FUNCTION { format.authors } 1140 | { 1141 | author empty.or.unknown 1142 | { "" } 1143 | { 1144 | "\bibfield{author}{" 1145 | author format.names add.period$ * "}" *} % jtb: add period if none before 1146 | if$ 1147 | } 1148 | 1149 | FUNCTION { format.key } 1150 | { 1151 | empty.or.unknown 1152 | { key field.or.null } 1153 | { "" } 1154 | if$ 1155 | } 1156 | 1157 | FUNCTION { format.no.key } 1158 | { 1159 | empty.or.unknown 1160 | { "" } 1161 | { "" } 1162 | if$ 1163 | } 1164 | 1165 | FUNCTION { format.editors.fml } 1166 | { 1167 | % Format editor names for use in the "in" types: inbook, incollection, 1168 | % inproceedings: first initial, then last names. When editors are the 1169 | % LABEL for an entry, then format.editor is used which lists editors 1170 | % by last name first. 1171 | 1172 | editor empty.or.unknown 1173 | { "" } 1174 | { 1175 | "\bibfield{editor}{" 1176 | editor format.names.fml 1177 | * "}" * 1178 | editor num.names$ #1 > 1179 | { " (Eds.)" * } 1180 | { " (Ed.)" * } 1181 | if$ 1182 | } 1183 | if$ 1184 | } 1185 | 1186 | FUNCTION { format.editors } 1187 | { % format editor names for use in labels, last names first. 1188 | editor empty.or.unknown 1189 | { "" } 1190 | { 1191 | "\bibfield{editor}{" 1192 | editor format.names 1193 | * "}" * 1194 | editor num.names$ #1 > 1195 | { " (Eds.)." * } 1196 | { " (Ed.)." * } 1197 | if$ 1198 | } 1199 | if$ 1200 | } 1201 | 1202 | FUNCTION { format.articletitle } 1203 | { 1204 | title empty.or.unknown 1205 | { "" } 1206 | % Use this to preserve lettercase in titles: 1207 | { "\showarticletitle{" title * "}" * } 1208 | % Use this for downcase title style: 1209 | % { \showarticletitle{" title "t" change.case$ * "}" * } 1210 | if$ 1211 | } 1212 | 1213 | FUNCTION { format.title } 1214 | { 1215 | title empty.or.unknown 1216 | { "" } 1217 | % Use this to preserve lettercase in titles: 1218 | { "\bibinfo{title}{" title * "}" * } 1219 | % Use this for downcase title style: 1220 | % { title "t" change.case$ } 1221 | if$ 1222 | } 1223 | 1224 | FUNCTION { n.dashify } 1225 | { 1226 | 't := 1227 | "" 1228 | { t empty.or.unknown not } 1229 | { 1230 | t #1 #1 substring$ "-" = 1231 | { 1232 | t #1 #2 substring$ "--" = not 1233 | { "--" * 1234 | t #2 global.max$ substring$ 't := 1235 | } 1236 | { 1237 | { t #1 #1 substring$ "-" = } 1238 | { 1239 | "-" * 1240 | t #2 global.max$ substring$ 't := 1241 | } 1242 | while$ 1243 | } 1244 | if$ 1245 | } 1246 | { 1247 | t #1 #1 substring$ * 1248 | t #2 global.max$ substring$ 't := 1249 | } 1250 | if$ 1251 | } 1252 | while$ 1253 | } 1254 | 1255 | FUNCTION { format.a.title.with.edition } 1256 | { 1257 | "\bibinfo{booktitle}{" 1258 | swap$ emphasize * 1259 | edition empty.or.unknown 1260 | 'skip$ 1261 | { " (\bibinfo{edition}{" * edition "l" change.case$ * 1262 | "} ed.)" * } % jtb: no parens for ed. 1263 | if$ 1264 | "}" * 1265 | } 1266 | 1267 | FUNCTION { format.btitle } 1268 | { title format.a.title.with.edition } 1269 | 1270 | FUNCTION { format.emphasize.booktitle } 1271 | { booktitle format.a.title.with.edition } 1272 | 1273 | 1274 | 1275 | FUNCTION { format.city } 1276 | { 1277 | % jtb: if the preceding string (the title of the conference) is non-empty, 1278 | % jtb: append the location, otherwise leave empty (so as to trigger the 1279 | % jtb: error message in output.check 1280 | 1281 | duplicate$ empty.or.unknown 1282 | { } 1283 | { 1284 | city empty.or.unknown location empty.or.unknown and 1285 | { 1286 | date empty.or.unknown 1287 | { } 1288 | { " (" * date * ")" * } 1289 | if$ 1290 | } 1291 | { 1292 | location empty.or.unknown 1293 | { 1294 | date empty.or.unknown 1295 | { " (" * city * ")" * } 1296 | { " (" * city * ", " * date * ")" * } 1297 | if$ 1298 | } 1299 | { 1300 | date empty.or.unknown 1301 | { " (" * location * ")" * } 1302 | { " (" * location * ", " * date * ")" * } 1303 | if$ 1304 | } 1305 | if$ 1306 | } 1307 | if$ 1308 | } 1309 | if$ 1310 | } 1311 | 1312 | FUNCTION { tie.or.space.connect } 1313 | { 1314 | duplicate$ text.length$ #3 < 1315 | { "~" } 1316 | { " " } 1317 | if$ 1318 | swap$ * * 1319 | } 1320 | 1321 | FUNCTION { either.or.check } 1322 | { 1323 | empty.or.unknown 1324 | 'pop$ 1325 | { "can't use both " swap$ * " fields in " * cite$ * warning$ } 1326 | if$ 1327 | } 1328 | 1329 | FUNCTION { format.bvolume } 1330 | { 1331 | % jtb: If there is a series, this is added and the volume trails after it. 1332 | % jtb: Otherwise, "Vol" is Capitalized. 1333 | 1334 | volume empty.or.unknown 1335 | { "" } 1336 | { 1337 | series empty.or.unknown 1338 | { "Vol.~\bibinfo{volume}{" volume "}" * *} 1339 | { "\bibinfo{series}{" series "}, " * * 1340 | "Vol.~\bibinfo{volume}{" volume "}" * * *} 1341 | if$ 1342 | "volume and number" number either.or.check 1343 | } 1344 | if$ 1345 | } 1346 | 1347 | FUNCTION { format.bvolume.noseries } 1348 | { 1349 | volume empty.or.unknown 1350 | { "" } 1351 | { "Vol.~\bibinfo{volume}{" volume "}" * * 1352 | "volume and number" number either.or.check 1353 | } 1354 | if$ 1355 | } 1356 | 1357 | FUNCTION { format.series } 1358 | { 1359 | series empty.or.unknown 1360 | {""} 1361 | {" \emph{(\bibinfo{series}{" * series "}" * 1362 | volume empty.or.unknown 1363 | { 1364 | number empty.or.unknown 1365 | {")}" *} 1366 | {", \bibinfo{number}{" number "})}" * * *} 1367 | if$ 1368 | } 1369 | {", Vol.~\bibinfo{volume}{" volume "})}" * * * 1370 | "volume and number" number either.or.check 1371 | } 1372 | if$ 1373 | } 1374 | if$ 1375 | } 1376 | 1377 | FUNCTION { format.number.series } 1378 | { 1379 | volume empty.or.unknown 1380 | { 1381 | number empty.or.unknown 1382 | { 1383 | volume empty.or.unknown 1384 | { "" } 1385 | { 1386 | series empty.or.unknown 1387 | { "" } 1388 | { " (\bibinfo{series}{" series * "})" * } 1389 | if$ 1390 | } 1391 | if$ 1392 | } % { series field.or.null } 1393 | { 1394 | output.state mid.sentence = 1395 | { "Number" } % gnp - changed to mixed case always 1396 | { "Number" } 1397 | if$ 1398 | number tie.or.space.connect series empty.or.unknown 1399 | { "there's a number but no series in " cite$ * warning$ } 1400 | { " in \bibinfo{series}{" * series * "}" * } 1401 | if$ 1402 | } 1403 | if$ 1404 | } 1405 | { 1406 | "" 1407 | } 1408 | if$ 1409 | } 1410 | 1411 | FUNCTION { multi.page.check } 1412 | { 1413 | 't := 1414 | #0 'multiresult := 1415 | { multiresult not 1416 | t empty.or.unknown not 1417 | and 1418 | } 1419 | { t #1 #1 substring$ 1420 | duplicate$ "-" = 1421 | swap$ duplicate$ "," = 1422 | swap$ "+" = 1423 | or or 1424 | { #1 'multiresult := } 1425 | { t #2 global.max$ substring$ 't := } 1426 | if$ 1427 | } 1428 | while$ 1429 | multiresult 1430 | } 1431 | 1432 | FUNCTION { format.pages } 1433 | { 1434 | pages empty.or.unknown 1435 | { "" } 1436 | { "\bibinfo{pages}{" 1437 | pages multi.page.check 1438 | { pages n.dashify } % gnp - removed () % jtb: removed pp. 1439 | { pages } 1440 | if$ 1441 | * "}" * 1442 | } 1443 | if$ 1444 | } 1445 | 1446 | FUNCTION { format.pages.check.without.articleno } 1447 | { %% format pages field only if articleno is absent 1448 | %% Stack out: pages-specification 1449 | numpages missing$ pages missing$ and 1450 | { "page numbers missing in both pages and numpages fields in " cite$ * warning$ } 1451 | { } 1452 | if$ 1453 | 1454 | articleno empty.or.unknown eid empty.or.unknown and 1455 | { 1456 | pages missing$ 1457 | { 1458 | numpages empty.or.unknown 1459 | {""} 1460 | { "\bibinfo{numpages}{" numpages * "}~pages" * } 1461 | if$ 1462 | } 1463 | { format.pages } 1464 | if$ 1465 | } 1466 | { "" } 1467 | if$ 1468 | } 1469 | 1470 | FUNCTION { format.pages.check } 1471 | { 1472 | pages empty.or.unknown 1473 | { "page numbers missing in " cite$ * warning$ "" } 1474 | { pages n.dashify } 1475 | if$ 1476 | } 1477 | 1478 | FUNCTION { format.bookpages } 1479 | { 1480 | bookpages empty.or.unknown 1481 | { "" } 1482 | { bookpages "book pages" tie.or.space.connect } 1483 | if$ 1484 | } 1485 | 1486 | FUNCTION { format.named.pages } 1487 | { 1488 | pages empty.or.unknown 1489 | { "" } 1490 | { format.pages "pages" tie.or.space.connect } 1491 | if$ 1492 | } 1493 | 1494 | % 1495 | % Changed by Boris Veytsman, 2011-03-13 1496 | % Now the word "pages" is printed even if 1497 | % there field pages is not empty. 1498 | % 1499 | 1500 | FUNCTION { format.page.count } 1501 | { 1502 | page.count empty.or.unknown 1503 | { "" } 1504 | { "\bibinfo{numpages}{" page.count * "}~pages" * } 1505 | if$ 1506 | } 1507 | 1508 | FUNCTION { format.articleno.numpages } 1509 | { 1510 | %% There are seven possible outputs, depending on which fields are set. 1511 | %% 1512 | %% These four are handled here: 1513 | %% 1514 | %% articleno, numpages, pages -> "Article articleno-value, numpages-value pages" 1515 | %% articleno, numpages -> "Article articleno-value, numpages-value pages" 1516 | %% articleno, pages -> "Article articleno-value, reduced-pages-value pages" 1517 | %% articleno -> "Article articleno-value" and warn about missing numpages 1518 | %% 1519 | %% The remaining three have already been handled by 1520 | %% format.pages.check.without.articleno: 1521 | %% 1522 | %% numpages, pages -> "pages-value" 1523 | %% numpages -> "numpages-value" 1524 | %% pages -> "pages-value" 1525 | %% 1526 | %% We no longer issue warninig when missing articleno, but having numpages 1527 | 1528 | articleno empty.or.unknown eid empty.or.unknown and 1529 | { 1530 | %% numpages empty.or.unknown 1531 | %% { } 1532 | %% { "numpages field, but no articleno or eid field, in " 1533 | %% cite$ * warning$ } 1534 | %% if$ 1535 | "" 1536 | } 1537 | { 1538 | numpages empty.or.unknown 1539 | { 1540 | pages empty.or.unknown 1541 | { 1542 | "articleno or eid, but no pages or numpages field in " 1543 | cite$ * warning$ 1544 | "" 'page.count := 1545 | } 1546 | { reduce.pages.to.page.count } 1547 | if$ 1548 | } 1549 | { numpages 'page.count := } 1550 | if$ 1551 | 1552 | %% The Article number is now handled in format.day.month.year because 1553 | %% ACM prefers the style "Digital Libraries 12, 3, Article 5 (July 2008)" 1554 | %% over "Digital Libraries 12, 3 (July 2008), Article 5" 1555 | %% format.articleno output 1556 | format.page.count 1557 | } 1558 | if$ 1559 | } 1560 | 1561 | FUNCTION {calc.format.page.count} 1562 | { 1563 | numpages empty.or.unknown 1564 | { 1565 | pages empty.or.unknown 1566 | { 1567 | "" 'page.count := 1568 | } 1569 | { reduce.pages.to.page.count } 1570 | if$ 1571 | } 1572 | { numpages 'page.count := } 1573 | if$ 1574 | format.page.count 1575 | } 1576 | 1577 | 1578 | FUNCTION { journal.canon.abbrev } 1579 | { 1580 | % Returns a canonical abbreviation for 'journal', or else 'journal' 1581 | % unchanged. 1582 | journal "ACM Computing Surveys" = { "Comput. Surveys" } { 1583 | journal "{ACM} Computing Surveys" = { "Comput. Surveys" } { 1584 | journal "ACM Transactions on Mathematical Software" = { "ACM Trans. Math. Software" } { 1585 | journal "{ACM} Transactions on Mathematical Software" = { "ACM Trans. Math. Software" } { 1586 | journal "ACM SIGNUM Newsletter" = { "ACM SIGNUM Newslett." } { 1587 | journal "ACM {SIGNUM} Newsletter" = { "ACM SIGNUM Newslett." } { 1588 | journal "{ACM} SIGNUM Newsletter" = { "ACM SIGNUM Newslett." } { 1589 | journal "{ACM} {SIGNUM} Newsletter" = { "ACM SIGNUM Newslett." } { 1590 | journal "American Journal of Sociology" = { "Amer. J. Sociology" } { 1591 | journal "American Mathematical Monthly" = { "Amer. Math. Monthly" } { 1592 | journal "American Mathematical Society Translations" = { "Amer. Math. Soc. Transl." } { 1593 | journal "Applied Mathematics and Computation" = { "Appl. Math. Comput." } { 1594 | journal "British Journal of Mathematical and Statistical Psychology" = { "Brit. J. Math. Statist. Psych." } { 1595 | journal "Bulletin of the American Mathematical Society" = { "Bull. Amer. Math. Soc." } { 1596 | journal "Canadian Mathematical Bulletin" = { "Canad. Math. Bull." } { 1597 | journal "Communications of the ACM" = { "Commun. ACM" } { 1598 | journal "Communications of the {ACM}" = { "Commun. ACM" } { 1599 | journal "Computers and Structures" = { "Comput. \& Structures" } { 1600 | journal "Contemporary Mathematics" = { "Contemp. Math." } { 1601 | journal "Crelle's Journal" = { "Crelle's J." } { 1602 | journal "Giornale di Mathematiche" = { "Giorn. Mat." } { 1603 | journal "IEEE Transactions on Aerospace and Electronic Systems" = { "IEEE Trans. Aerospace Electron. Systems" } { 1604 | journal "{IEEE} Transactions on Aerospace and Electronic Systems" = { "IEEE Trans. Aerospace Electron. Systems" } { 1605 | journal "IEEE Transactions on Automatic Control" = { "IEEE Trans. Automat. Control" } { 1606 | journal "{IEEE} Transactions on Automatic Control" = { "IEEE Trans. Automat. Control" } { 1607 | journal "IEEE Transactions on Computers" = { "IEEE Trans. Comput." } { 1608 | journal "{IEEE} Transactions on Computers" = { "IEEE Trans. Comput." } { 1609 | journal "IMA Journal of Numerical Analysis" = { "IMA J. Numer. Anal." } { 1610 | journal "{IMA} Journal of Numerical Analysis" = { "IMA J. Numer. Anal." } { 1611 | journal "Information Processing Letters" = { "Inform. Process. Lett." } { 1612 | journal "International Journal for Numerical Methods in Engineering" = { "Internat. J. Numer. Methods Engrg." } { 1613 | journal "International Journal of Control" = { "Internat. J. Control" } { 1614 | journal "International Journal of Supercomputing Applications" = { "Internat. J. Supercomputing Applic." } { 1615 | journal "Journal of Computational Physics" = { "J. Comput. Phys." } { 1616 | journal "Journal of Computational and Applied Mathematics" = { "J. Comput. Appl. Math." } { 1617 | journal "Journal of Computer and System Sciences" = { "J. Comput. System Sci." } { 1618 | journal "Journal of Mathematical Analysis and Applications" = { "J. Math. Anal. Appl." } { 1619 | journal "Journal of Mathematical Physics" = { "J. Math. Phys." } { 1620 | journal "Journal of Parallel and Distributed Computing" = { "J. Parallel and Distrib. Comput." } { 1621 | journal "Journal of Research of the National Bureau of Standards" = { "J. Res. Nat. Bur. Standards" } { 1622 | journal "Journal of VLSI and Computer Systems" = { "J. VLSI Comput. Syst." } { 1623 | journal "Journal of {VLSI} and Computer Systems" = { "J. VLSI Comput. Syst." } { 1624 | journal "Journal of the ACM" = { "J. ACM" } { 1625 | journal "Journal of the American Statistical Association" = { "J. Amer. Statist. Assoc." } { 1626 | journal "Journal of the Institute of Mathematics and its Applications" = { "J. Inst. Math. Appl." } { 1627 | journal "Journal of the Society for Industrial and Applied Mathematics" = { "J. Soc. Indust. Appl. Math." } { 1628 | journal "Journal of the Society for Industrial and Applied Mathematics, Series B, Numerical Analysis" = { "J. Soc. Indust. Appl. Math. Ser. B Numer. Anal." } { 1629 | journal "Linear Algebra and its Applications" = { "Linear Algebra Appl." } { 1630 | journal "Mathematica Scandinavica" = { "Math. Scand." } { 1631 | journal "Mathematical Tables and Other Aids to Computation" = { "Math. Tables Aids Comput." } { 1632 | journal "Mathematics of Computation" = { "Math. Comp." } { 1633 | journal "Mathematische Annalen" = { "Math. Ann." } { 1634 | journal "Numerische Mathematik" = { "Numer. Math." } { 1635 | journal "Pacific Journal of Mathematics" = { "Pacific J. Math." } { 1636 | journal "Parallel Computing" = { "Parallel Comput." } { 1637 | journal "Philosophical Magazine" = { "Philos. Mag." } { 1638 | journal "Proceedings of the American Mathematical Society" = { "Proc. Amer. Math. Soc." } { 1639 | journal "Proceedings of the IEEE" = { "Proc. IEEE" } { 1640 | journal "Proceedings of the {IEEE}" = { "Proc. IEEE" } { 1641 | journal "Proceedings of the National Academy of Sciences of the USA" = { "Proc. Nat. Acad. Sci. U. S. A." } { 1642 | journal "Quarterly Journal of Mathematics, Oxford, Series (2)" = { "Quart. J. Math. Oxford Ser. (2)" } { 1643 | journal "Quarterly of Applied Mathematics" = { "Quart. Appl. Math." } { 1644 | journal "Review of the International Statisical Institute" = { "Rev. Inst. Internat. Statist." } { 1645 | journal "SIAM Journal on Algebraic and Discrete Methods" = { "SIAM J. Algebraic Discrete Methods" } { 1646 | journal "{SIAM} Journal on Algebraic and Discrete Methods" = { "SIAM J. Algebraic Discrete Methods" } { 1647 | journal "SIAM Journal on Applied Mathematics" = { "SIAM J. Appl. Math." } { 1648 | journal "{SIAM} Journal on Applied Mathematics" = { "SIAM J. Appl. Math." } { 1649 | journal "SIAM Journal on Computing" = { "SIAM J. Comput." } { 1650 | journal "{SIAM} Journal on Computing" = { "SIAM J. Comput." } { 1651 | journal "SIAM Journal on Matrix Analysis and Applications" = { "SIAM J. Matrix Anal. Appl." } { 1652 | journal "{SIAM} Journal on Matrix Analysis and Applications" = { "SIAM J. Matrix Anal. Appl." } { 1653 | journal "SIAM Journal on Numerical Analysis" = { "SIAM J. Numer. Anal." } { 1654 | journal "{SIAM} Journal on Numerical Analysis" = { "SIAM J. Numer. Anal." } { 1655 | journal "SIAM Journal on Scientific and Statistical Computing" = { "SIAM J. Sci. Statist. Comput." } { 1656 | journal "{SIAM} Journal on Scientific and Statistical Computing" = { "SIAM J. Sci. Statist. Comput." } { 1657 | journal "SIAM Review" = { "SIAM Rev." } { 1658 | journal "{SIAM} Review" = { "SIAM Rev." } { 1659 | journal "Software Practice and Experience" = { "Software Prac. Experience" } { 1660 | journal "Statistical Science" = { "Statist. Sci." } { 1661 | journal "The Computer Journal" = { "Comput. J." } { 1662 | journal "Transactions of the American Mathematical Society" = { "Trans. Amer. Math. Soc." } { 1663 | journal "USSR Computational Mathematics and Mathematical Physics" = { "U. S. S. R. Comput. Math. and Math. Phys." } { 1664 | journal "{USSR} Computational Mathematics and Mathematical Physics" = { "U. S. S. R. Comput. Math. and Math. Phys." } { 1665 | journal "Zeitschrift fur Angewandte Mathematik und Mechanik" = { "Z. Angew. Math. Mech." } { 1666 | journal "Zeitschrift fur Angewandte Mathematik und Physik" = { "Z. Angew. Math. Phys." } { 1667 | journal 1668 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1669 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1670 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1671 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1672 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1673 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1674 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1675 | } if$ } if$ } if$ } if$ } if$ } if$ } if$ } if$ 1676 | } 1677 | 1678 | FUNCTION { format.journal.volume.number.day.month.year } 1679 | { 1680 | % By Young (and Spencer) 1681 | % GNP - fixed bugs with missing volume, number, and/or pages 1682 | % 1683 | % Format journal, volume, number, pages for article types. 1684 | % 1685 | journal empty.or.unknown 1686 | { "no journal in " cite$ * warning$ "" } 1687 | { "\bibinfo{journal}{" 1688 | journal.canon.abbrev emphasize * 1689 | "}" * } 1690 | if$ 1691 | 1692 | number empty.or.unknown 1693 | { 1694 | volume empty.or.unknown 1695 | { "no number and no volume in " cite$ * warning$ "" * } 1696 | { " " * " \bibinfo{volume}{" * volume * "}" * } 1697 | if$ 1698 | } 1699 | { 1700 | volume empty.or.unknown 1701 | { 1702 | "unusual to have number, but no volume, for " cite$ * warning$ 1703 | " \bibinfo{number}{" * number * "}" * 1704 | } 1705 | { " \bibinfo{volume}{" * volume * "}, \bibinfo{number}{" * 1706 | number * "}" *} 1707 | if$ 1708 | } 1709 | if$ 1710 | after.block 'output.state := 1711 | 1712 | % Sometimes proceedings are published in journals 1713 | % In this case we do not want to put year, day and month here 1714 | 1715 | type$ "inproceedings" = 1716 | { } 1717 | {format.day.month.year * } 1718 | if$ 1719 | } 1720 | 1721 | FUNCTION { format.chapter.pages } 1722 | { 1723 | chapter empty.or.unknown 1724 | 'format.pages 1725 | { type empty.or.unknown 1726 | { "Chapter" } % gnp - changed to mixed case 1727 | { type "t" change.case$ } 1728 | if$ 1729 | chapter tie.or.space.connect 1730 | pages empty.or.unknown 1731 | {"page numbers missing in " cite$ * warning$} % gnp - added check 1732 | { ", " * format.pages * } 1733 | if$ 1734 | } 1735 | if$ 1736 | } 1737 | 1738 | FUNCTION { format.in.emphasize.booktitle } 1739 | { % jtb: format for collections or proceedings not appearing in a journal 1740 | booktitle empty.or.unknown 1741 | { "" } 1742 | { "In " format.emphasize.booktitle * } 1743 | if$ 1744 | } 1745 | 1746 | FUNCTION { format.in.booktitle } 1747 | { % jtb: format for proceedings appearing in a journal 1748 | booktitle empty.or.unknown 1749 | { "" } 1750 | { "In \bibinfo{booktitle}{" booktitle * "}" * } 1751 | if$ 1752 | } 1753 | 1754 | FUNCTION { format.in.ed.booktitle } 1755 | { 1756 | booktitle empty.or.unknown 1757 | { "" } 1758 | { editor empty.or.unknown 1759 | { "In " format.emphasize.booktitle * } 1760 | % jtb: swapped editor location 1761 | { "In " format.emphasize.booktitle * ", " * format.editors.fml * } 1762 | if$ 1763 | } 1764 | if$ 1765 | } 1766 | 1767 | FUNCTION { format.thesis.type } 1768 | { % call with default type on stack top 1769 | type empty.or.unknown 1770 | 'skip$ % use default type 1771 | { 1772 | pop$ % discard default type 1773 | % NO: it is silly to have to brace protect every degree type!: type "t" change.case$ 1774 | type 1775 | } 1776 | if$ 1777 | } 1778 | 1779 | FUNCTION { format.tr.number } 1780 | { 1781 | "\bibinfo{type}{" 1782 | type empty.or.unknown 1783 | { "{T}echnical {R}eport" } 1784 | 'type 1785 | if$ 1786 | "}" * * 1787 | number empty.or.unknown 1788 | { "t" change.case$ } 1789 | %% LOOKS BAD: { "." * number tie.or.space.connect } 1790 | %% Prefer "Research report RJ687." to "Research report. RJ687." 1791 | { number tie.or.space.connect } 1792 | if$ 1793 | } 1794 | 1795 | FUNCTION { format.advisor } 1796 | { 1797 | advisor empty.or.unknown 1798 | { "" } 1799 | { "Advisor(s) " advisor * } 1800 | if$ 1801 | } 1802 | 1803 | FUNCTION { format.article.crossref } 1804 | { "See" 1805 | "\citeN{" * crossref * "}" * 1806 | } 1807 | 1808 | FUNCTION { format.crossref.editor } 1809 | { 1810 | editor #1 "{vv~}{ll}" format.name$ 1811 | editor num.names$ duplicate$ 1812 | #2 > 1813 | { pop$ " et~al\mbox{.}" * } % jrh: avoid spacing problems 1814 | { #2 < 1815 | 'skip$ 1816 | { editor #2 "{ff }{vv }{ll}{ jj}" format.name$ "others" = 1817 | { " et~al\mbox{.}" * } % jrh: avoid spacing problems 1818 | { " and " * editor #2 "{vv~}{ll}" format.name$ * } 1819 | if$ 1820 | } 1821 | if$ 1822 | } 1823 | if$ 1824 | } 1825 | 1826 | FUNCTION { format.book.crossref } 1827 | { 1828 | volume empty.or.unknown 1829 | { "empty volume in " cite$ * "'s crossref of " * crossref * warning$ 1830 | "In " 1831 | } 1832 | { "Volume" volume tie.or.space.connect % gnp - changed to mixed case 1833 | " of " * 1834 | } 1835 | if$ 1836 | editor empty.or.unknown 1837 | editor field.or.null author field.or.null = 1838 | or 1839 | { key empty.or.unknown 1840 | { series empty.or.unknown 1841 | { "need editor, key, or series for " cite$ * " to crossref " * 1842 | crossref * warning$ 1843 | "" * 1844 | } 1845 | { series emphasize * } 1846 | if$ 1847 | } 1848 | { key * } 1849 | if$ 1850 | } 1851 | { format.crossref.editor * } 1852 | if$ 1853 | " \citeN{" * crossref * "}" * 1854 | } 1855 | 1856 | FUNCTION { format.incoll.inproc.crossref } 1857 | { "See" 1858 | " \citeN{" * crossref * "}" * 1859 | } 1860 | 1861 | FUNCTION { format.lab.names } 1862 | { 1863 | % format.lab.names: 1864 | % 1865 | % determines "short" names for the abbreviated author information. 1866 | % "Long" labels are created in calc.label, using the routine my.full.label 1867 | % to format author and editor fields. 1868 | % 1869 | % There are 4 cases for labels. (n=3 in the example) 1870 | % a) one author Foo 1871 | % b) one to n Foo, Bar and Baz 1872 | % c) use of "and others" Foo, Bar et al. 1873 | % d) more than n Foo et al. 1874 | 1875 | 's := 1876 | s num.names$ 'numnames := 1877 | numnames #2 > % change number to number of others allowed before 1878 | % forcing "et al". 1879 | { s #1 "{vv~}{ll}" format.name$ " et~al\mbox{.}" * } % jrh: \mbox{} added 1880 | { 1881 | numnames #1 - 'namesleft := 1882 | #2 'nameptr := 1883 | s #1 "{vv~}{ll}" format.name$ 1884 | { namesleft #0 > } 1885 | { nameptr numnames = 1886 | { s nameptr "{ff }{vv }{ll}{ jj}" format.name$ "others" = 1887 | { " et~al\mbox{.}" * } % jrh: avoid spacing problems 1888 | { " and " * s nameptr "{vv~}{ll}" format.name$ * } 1889 | if$ 1890 | } 1891 | { ", " * s nameptr "{vv~}{ll}" format.name$ * } 1892 | if$ 1893 | nameptr #1 + 'nameptr := 1894 | namesleft #1 - 'namesleft := 1895 | } 1896 | while$ 1897 | } 1898 | if$ 1899 | } 1900 | 1901 | FUNCTION { author.key.label } 1902 | { 1903 | author empty.or.unknown 1904 | { key empty.or.unknown 1905 | { "no key, author in " cite$ * warning$ 1906 | cite$ #1 #3 substring$ } 1907 | 'key 1908 | if$ 1909 | } 1910 | { author format.lab.names } 1911 | if$ 1912 | } 1913 | 1914 | FUNCTION { editor.key.organization.label } 1915 | { % added - gnp. Provide label formatting by organization if editor is null. 1916 | editor empty.or.unknown 1917 | { organization empty.or.unknown 1918 | { key empty.or.unknown 1919 | { "no key, editor or organization in " cite$ * warning$ 1920 | cite$ #1 #3 substring$ } 1921 | 'key 1922 | if$ 1923 | } 1924 | { organization } 1925 | if$ 1926 | } 1927 | { editor format.lab.names } 1928 | if$ 1929 | } 1930 | 1931 | FUNCTION { author.editor.key.label } 1932 | { 1933 | author empty.or.unknown 1934 | { editor empty.or.unknown 1935 | { key empty.or.unknown 1936 | { "no key, author, or editor in " cite$ * warning$ 1937 | cite$ #1 #3 substring$ } 1938 | 'key 1939 | if$ 1940 | } 1941 | { editor format.lab.names } 1942 | if$ 1943 | } 1944 | { author format.lab.names } 1945 | if$ 1946 | } 1947 | 1948 | FUNCTION { author.editor.key.organization.label } 1949 | { % added - gnp. Provide label formatting by organization if author is null. 1950 | author empty.or.unknown 1951 | { editor empty.or.unknown 1952 | { organization empty.or.unknown 1953 | { key empty.or.unknown 1954 | { "no key, author, editor or organization in " cite$ * warning$ 1955 | cite$ #1 #3 substring$ } 1956 | 'key 1957 | if$ 1958 | } 1959 | { organization } 1960 | if$ 1961 | } 1962 | { editor format.lab.names } 1963 | if$ 1964 | } 1965 | { author format.lab.names } 1966 | if$ 1967 | } 1968 | 1969 | % Calculate label and leave it on stack 1970 | FUNCTION { calc.basic.label } 1971 | { 1972 | type$ "book" = 1973 | type$ "inbook" = 1974 | or 1975 | type$ "article" = 1976 | or 1977 | 'author.editor.key.label 1978 | { type$ "proceedings" = 1979 | type$ "periodical" = 1980 | or 1981 | 'editor.key.organization.label 1982 | { type$ "manual" = 1983 | 'author.editor.key.organization.label 1984 | 'author.key.label 1985 | if$ 1986 | } 1987 | if$ 1988 | } 1989 | if$ 1990 | duplicate$ 1991 | year empty.or.unknown 1992 | { "[n.d.]" } 1993 | { year field.or.null purify$ #-1 #4 substring$} 1994 | if$ 1995 | * 1996 | 'basic.label.year := 1997 | } 1998 | 1999 | FUNCTION { calc.label } 2000 | { 2001 | % Changed - GNP. See also author.editor.organization.sort, editor.organization.sort 2002 | % Form label for BibTeX entry. The classification of which fields are used 2003 | % for which type of entry (book, inbook, etc.) are taken from alpha.bst. 2004 | % The change here from newapa is to also include organization as a 2005 | % citation label if author or editor is missing. 2006 | 2007 | calc.basic.label 2008 | 2009 | author empty.or.unknown % generate the full label citation information. 2010 | { 2011 | editor empty.or.unknown 2012 | { 2013 | organization empty.or.unknown 2014 | { 2015 | key empty.or.unknown 2016 | { 2017 | "no author, editor, organization, or key in " cite$ * warning$ 2018 | "??" 2019 | } 2020 | { key } 2021 | if$ 2022 | } 2023 | { organization } 2024 | if$ 2025 | } 2026 | { editor my.full.label } 2027 | if$ 2028 | } 2029 | { author my.full.label } 2030 | if$ 2031 | 2032 | % leave label on the stack, to be popped when required. 2033 | 2034 | "}{" * swap$ * "}{" * 2035 | % year field.or.null purify$ #-1 #4 substring$ * 2036 | % 2037 | % save the year for sort processing afterwards (adding a, b, c, etc.) 2038 | % 2039 | year empty.or.unknown 2040 | { "[n.d.]" } 2041 | { year field.or.null purify$ #-1 #4 substring$} 2042 | if$ 2043 | 'label.year := 2044 | } 2045 | 2046 | 2047 | FUNCTION { output.bibitem } 2048 | { 2049 | newline$ 2050 | "\bibitem[\protect\citeauthoryear{" write$ 2051 | calc.label write$ 2052 | sort.year write$ 2053 | "}]%" writeln 2054 | " {" write$ 2055 | cite$ write$ 2056 | "}" writeln 2057 | "" 2058 | before.all 'output.state := 2059 | } 2060 | 2061 | 2062 | FUNCTION { output.issue.doi.coden.isxn.lccn.url.eprint } 2063 | { % enter and return with stack empty 2064 | %% We switch now from buffered output to output of complete lines, so 2065 | %% that the Issue .. URL data have their own lines, and are less likely 2066 | %% to be line-wrapped by BibTeX's short-sighted algorithm, which wraps 2067 | %% lines longer than 79 characters, backtracking to what it thinks is 2068 | %% a break point in the string. Any such wrapping MUST be undone to 2069 | %% prevent percent-newline from appearing in DOIs and URLs. The 2070 | %% output data are intentionally wrapped in \showxxx{} macros at 2071 | %% beginning of line, and that supply their own punctuation (if they 2072 | %% are not defined to suppress output entirely), to make it easier for 2073 | %% other software to recover them from .bbl files. 2074 | %% 2075 | %% It also makes it possible to later change the macro definitions 2076 | %% to suppress particular output values, or alter their appearance. 2077 | %% 2078 | %% Note that it is possible for theses, technical reports, and 2079 | %% manuals to have ISBNs, and anything that has an ISBN may also 2080 | %% have an ISSN. When there are no values for these keys, there 2081 | %% is no output generated for them here. 2082 | 2083 | "\newblock" writeln 2084 | after.block 'output.state := 2085 | 2086 | output.issue 2087 | output.isbn 2088 | output.coden % CODEN is functionally like ISSN, so output them sequentially 2089 | output.issn 2090 | output.lccn 2091 | output.doi % DOI is ALWAYS last according to CrossRef DOI documentation 2092 | output.eprint 2093 | output.url % but ACM wants URL last 2094 | } 2095 | 2096 | FUNCTION { output.issue.doi.coden.isxn.lccn.url.eprint.note } 2097 | { % enter with stack empty, return with empty string on stack 2098 | output.issue.doi.coden.isxn.lccn.url.eprint 2099 | note empty.or.unknown 2100 | { } 2101 | { 2102 | "\newblock" writeln 2103 | output.note 2104 | } 2105 | if$ 2106 | "" 2107 | } 2108 | 2109 | FUNCTION { output.issue.doi.coden.isxn.lccn.url.eprint.note.check } 2110 | { % enter with stack empty, return with empty string on stack 2111 | output.issue.doi.coden.isxn.lccn.url.eprint 2112 | note empty.or.unknown 2113 | { } 2114 | { 2115 | "\newblock" writeln 2116 | output.note.check 2117 | } 2118 | if$ 2119 | "" 2120 | } 2121 | 2122 | FUNCTION { article } 2123 | { 2124 | output.bibitem 2125 | 2126 | author empty.or.unknown 2127 | { 2128 | editor empty.or.unknown 2129 | { "neither author and editor supplied for " cite$ * warning$ } 2130 | { format.editors "editor" output.check } 2131 | if$ 2132 | } 2133 | { format.authors "author" output.check } 2134 | if$ 2135 | 2136 | author format.no.key output % added 2137 | output.year.check % added 2138 | new.block 2139 | format.articletitle "title" output.check 2140 | new.block 2141 | howpublished empty.or.unknown 2142 | { } 2143 | { "\bibinfo{howpublished}{" howpublished "}" * * output } 2144 | if$ 2145 | 2146 | crossref missing$ 2147 | { format.journal.volume.number.day.month.year output} 2148 | { 2149 | "cross reference in @Article{...} is unusual" warning$ 2150 | format.article.crossref output.nonnull 2151 | } 2152 | if$ 2153 | 2154 | format.pages.check.without.articleno output 2155 | format.articleno.numpages output 2156 | fin.block 2157 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2158 | fin.entry 2159 | } 2160 | 2161 | FUNCTION { book } 2162 | { 2163 | output.bibitem 2164 | author empty.or.unknown 2165 | { format.editors "author and editor" output.check } 2166 | { format.authors output.nonnull 2167 | crossref missing$ 2168 | { "author and editor" editor either.or.check } 2169 | 'skip$ 2170 | if$ 2171 | } 2172 | if$ 2173 | output.year.check % added 2174 | new.block 2175 | format.btitle "title" output.check 2176 | crossref missing$ 2177 | { new.sentence % jtb: start a new sentence for series/volume 2178 | format.bvolume output 2179 | new.block 2180 | format.number.series output 2181 | new.sentence 2182 | publisher "publisher" bibinfo.output.check 2183 | address "address" bibinfo.output.check % jtb: require address 2184 | fin.sentence 2185 | pages empty.or.unknown 2186 | { format.bookpages } % use bookpages when pages empty 2187 | { format.pages.check "pages" tie.or.space.connect } 2188 | if$ 2189 | output 2190 | } 2191 | { new.block 2192 | format.book.crossref output.nonnull 2193 | } 2194 | if$ 2195 | fin.block 2196 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2197 | fin.entry 2198 | } 2199 | 2200 | FUNCTION { booklet } 2201 | { 2202 | output.bibitem 2203 | format.authors output 2204 | author format.key output % added 2205 | output.year.check % added 2206 | new.block 2207 | format.title "title" output.check 2208 | new.block 2209 | howpublished empty.or.unknown 2210 | { } 2211 | { "\bibinfo{howpublished}{" howpublished "}" * * output } 2212 | if$ 2213 | address output 2214 | fin.block 2215 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2216 | fin.entry 2217 | } 2218 | 2219 | FUNCTION { inbook } 2220 | { 2221 | output.bibitem 2222 | author empty.or.unknown 2223 | { format.editors 2224 | "author and editor" output.check 2225 | } 2226 | { format.authors output.nonnull 2227 | crossref missing$ 2228 | { "author and editor" editor either.or.check } 2229 | 'skip$ 2230 | if$ 2231 | } 2232 | if$ 2233 | output.year.check % added 2234 | new.block 2235 | format.btitle "title" output.check 2236 | crossref missing$ 2237 | { new.sentence % jtb: start a new sentence for series/volume 2238 | format.bvolume output 2239 | new.block 2240 | format.number.series output 2241 | new.sentence 2242 | publisher "publisher" bibinfo.output.check 2243 | address "address" bibinfo.output.check % jtb: require address 2244 | format.bookpages output 2245 | format.chapter.pages 2246 | "chapter and pages" output.check % jtb: moved from before publisher 2247 | } 2248 | { 2249 | format.bookpages output 2250 | format.chapter.pages "chapter and pages" output.check 2251 | new.block 2252 | format.book.crossref output.nonnull 2253 | } 2254 | if$ 2255 | fin.block 2256 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2257 | fin.entry 2258 | } 2259 | 2260 | FUNCTION { incollection } 2261 | { 2262 | output.bibitem 2263 | format.authors "author" output.check 2264 | author format.key output % added 2265 | output.year.check % added 2266 | new.block 2267 | format.articletitle "title" output.check 2268 | new.block 2269 | crossref missing$ 2270 | { format.in.ed.booktitle "booktitle" output.check 2271 | new.sentence % jtb: start a new sentence for series/volume 2272 | format.bvolume output 2273 | format.number.series output 2274 | new.sentence 2275 | publisher "publisher" bibinfo.output.check 2276 | address "address" bibinfo.output.check % jtb: require address 2277 | format.bookpages output 2278 | format.chapter.pages output % gnp - was special.output.nonnull 2279 | % left out comma before page numbers 2280 | % jtb: moved from before publisher 2281 | } 2282 | { 2283 | format.incoll.inproc.crossref output.nonnull 2284 | format.chapter.pages output 2285 | } 2286 | if$ 2287 | fin.block 2288 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2289 | fin.entry 2290 | } 2291 | 2292 | FUNCTION { inproceedings } 2293 | { 2294 | output.bibitem 2295 | format.authors "author" output.check 2296 | author format.key output % added 2297 | output.year.check % added 2298 | new.block 2299 | format.articletitle "title" output.check 2300 | howpublished empty.or.unknown 2301 | { } 2302 | { "\bibinfo{howpublished}{" howpublished "}" * * output.dot.space } 2303 | if$ 2304 | crossref missing$ 2305 | { 2306 | journal missing$ % jtb: proceedings appearing in journals 2307 | { format.in.emphasize.booktitle format.city "booktitle" output.check.dot.space 2308 | format.series output.removenospace 2309 | format.editors.fml output % BV 2011/09/27 Moved dot to comma 2310 | series empty.or.unknown 2311 | { format.bvolume.noseries output } 2312 | {} 2313 | if$ 2314 | new.sentence 2315 | organization output 2316 | publisher "publisher" bibinfo.output.check % jtb: require publisher (?) 2317 | address "address" bibinfo.output.check % jtb: require address 2318 | format.bookpages output 2319 | } 2320 | { 2321 | format.in.booktitle format.city "booktitle" output.check 2322 | format.editors.fml output 2323 | new.sentence 2324 | format.journal.volume.number.day.month.year output 2325 | } 2326 | if$ 2327 | format.articleno output 2328 | format.pages.check.without.articleno output 2329 | } 2330 | { 2331 | format.incoll.inproc.crossref output.nonnull 2332 | format.articleno output 2333 | format.pages.check.without.articleno output 2334 | } 2335 | if$ 2336 | format.articleno.numpages output 2337 | fin.block 2338 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2339 | fin.entry 2340 | } 2341 | 2342 | FUNCTION { conference } { inproceedings } 2343 | 2344 | FUNCTION { manual } 2345 | { 2346 | output.bibitem 2347 | author empty.or.unknown 2348 | { editor empty.or.unknown 2349 | { organization "organization" output.check 2350 | organization format.key output } % if all else fails, use key 2351 | { format.editors "author and editor" output.check } 2352 | if$ 2353 | } 2354 | { format.authors output.nonnull } 2355 | if$ 2356 | output.year.check % added 2357 | new.block 2358 | format.btitle "title" output.check 2359 | organization address new.block.checkb 2360 | % jtb: back to normal style: organization, address 2361 | organization "organization" output.check 2362 | address output 2363 | fin.block 2364 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2365 | fin.entry 2366 | } 2367 | 2368 | FUNCTION { mastersthesis } 2369 | { 2370 | output.bibitem 2371 | format.authors "author" output.check 2372 | author format.key output % added 2373 | output.year.check % added 2374 | new.block 2375 | format.title emphasize "title" output.check % NB: ACM style requires emphasized thesis title 2376 | new.block 2377 | "\bibinfo{thesistype}{Master's\ thesis}" format.thesis.type output 2378 | new.sentence 2379 | school "school" bibinfo.output.check 2380 | address empty.or.unknown 2381 | { } 2382 | { "\bibinfo{address}{" address * "}" * output } 2383 | if$ 2384 | new.block 2385 | format.advisor output 2386 | fin.block 2387 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2388 | fin.entry 2389 | } 2390 | 2391 | FUNCTION { misc } 2392 | { 2393 | output.bibitem 2394 | format.authors "author" output.check 2395 | author format.key output % added 2396 | output.year.check % added 2397 | title howpublished new.block.checkb 2398 | format.title output 2399 | new.block 2400 | howpublished empty.or.unknown 2401 | { } 2402 | { "\bibinfo{howpublished}{" howpublished "}" * * output } 2403 | if$ 2404 | "" output.nonnull.dot.space 2405 | calc.format.page.count output 2406 | fin.block 2407 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2408 | fin.entry 2409 | } 2410 | 2411 | FUNCTION { online } { manual } 2412 | 2413 | FUNCTION { game } { manual } 2414 | 2415 | FUNCTION { artifactsoftware } { manual } 2416 | 2417 | FUNCTION { artifactdataset } { manual } 2418 | 2419 | FUNCTION { software } { manual } 2420 | 2421 | FUNCTION { dataset } { manual } 2422 | 2423 | FUNCTION { phdthesis } 2424 | { 2425 | output.bibitem 2426 | format.authors "author" output.check 2427 | author format.key output % added 2428 | output.year.check % added 2429 | new.block 2430 | format.title emphasize "title" output.check % NB: ACM style requires emphasized thesis title 2431 | new.block 2432 | "\bibinfo{thesistype}{Ph.D. Dissertation}" format.thesis.type output 2433 | new.sentence 2434 | school "school" bibinfo.output.check 2435 | address empty.or.unknown 2436 | { } 2437 | { "\bibinfo{address}{" address * "}" * output } 2438 | if$ 2439 | new.block 2440 | format.advisor output 2441 | fin.block 2442 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2443 | fin.entry 2444 | } 2445 | 2446 | FUNCTION {format.date} 2447 | { year empty.or.unknown 2448 | { month empty.or.unknown 2449 | { 2450 | "" % output empty date if year/month both empty 2451 | day empty.or.unknown 2452 | { } 2453 | { "there's a day but no month or year in " cite$ * warning$ } 2454 | if$ 2455 | } 2456 | { "there's a month but no year in " cite$ * warning$ 2457 | month 2458 | day empty.or.unknown 2459 | { } 2460 | { " " * day * } 2461 | if$ 2462 | } 2463 | if$ 2464 | } 2465 | { month empty.or.unknown 2466 | { 2467 | year % output only year if month empty 2468 | day empty.or.unknown 2469 | { } 2470 | { "there's a day and year but no month in " cite$ * warning$ } 2471 | if$ 2472 | } 2473 | { 2474 | month " " * 2475 | day empty.or.unknown 2476 | { } 2477 | { day * ", " * } 2478 | if$ 2479 | year * 2480 | } 2481 | if$ 2482 | } 2483 | if$ 2484 | } 2485 | 2486 | FUNCTION {new.block.checka} 2487 | { 2488 | empty.or.unknown 2489 | 'skip$ 2490 | 'new.block 2491 | if$ 2492 | } 2493 | 2494 | FUNCTION { periodical } 2495 | { 2496 | output.bibitem 2497 | editor empty.or.unknown 2498 | { organization output } 2499 | { format.editors output.nonnull } 2500 | if$ 2501 | new.block 2502 | output.year.check 2503 | new.sentence 2504 | format.articletitle "title" output.check 2505 | format.journal.volume.number.day.month.year output 2506 | calc.format.page.count output 2507 | fin.entry 2508 | } 2509 | 2510 | FUNCTION { proceedings } 2511 | { 2512 | output.bibitem 2513 | editor empty.or.unknown 2514 | { organization output 2515 | organization format.key output } % gnp - changed from author format.key 2516 | { format.editors output.nonnull } 2517 | if$ 2518 | % author format.key output % gnp - removed (should be either 2519 | % editor or organization 2520 | output.year.check % added (newapa) 2521 | new.block 2522 | format.btitle format.city "title" output.check % jtb: added city 2523 | new.sentence 2524 | format.bvolume output 2525 | format.number.series output 2526 | new.sentence 2527 | organization output 2528 | % jtb: normal order: publisher, address 2529 | publisher empty.or.unknown 2530 | { } 2531 | { "\bibinfo{publisher}{" publisher * "}" * output } 2532 | if$ 2533 | address empty.or.unknown 2534 | { } 2535 | { "\bibinfo{address}{" address * "}" * output } 2536 | if$ 2537 | fin.block 2538 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2539 | fin.entry 2540 | } 2541 | 2542 | FUNCTION { collection } { proceedings } 2543 | 2544 | FUNCTION { techreport } 2545 | { 2546 | output.bibitem 2547 | format.authors "author" output.check 2548 | author format.key output % added 2549 | output.year.check % added 2550 | new.block 2551 | format.btitle "title" output.check 2552 | new.block 2553 | % format.tr.number output % jtb: moved month ... 2554 | format.tr.number output new.sentence % Gerry - need dot 2011/09/28 2555 | institution "institution" bibinfo.output.check 2556 | address empty.or.unknown 2557 | { } 2558 | { "\bibinfo{address}{" address "}" * * output } 2559 | if$ 2560 | new.sentence 2561 | format.named.pages output 2562 | % ACM omits year at end in transactions style 2563 | % format.day.month.year output.nonnull.dot.space % jtb: ... to here (no parens) 2564 | fin.block 2565 | output.issue.doi.coden.isxn.lccn.url.eprint.note 2566 | fin.entry 2567 | } 2568 | 2569 | FUNCTION { unpublished } 2570 | { 2571 | output.bibitem 2572 | format.authors 2573 | "author" output.check 2574 | author format.key output % added 2575 | output.year.check % added 2576 | new.block 2577 | format.title "title" output.check 2578 | fin.sentence 2579 | output.day.month.year % UTAH 2580 | calc.format.page.count output 2581 | fin.block 2582 | output.issue.doi.coden.isxn.lccn.url.eprint.note.check 2583 | fin.entry 2584 | } 2585 | 2586 | FUNCTION { default.type } { misc } 2587 | 2588 | %%% ACM journal-style month definitions: full name if 1--5 letters, else 2589 | %%% abbreviation of 3 or 4 characters and a dot 2590 | 2591 | MACRO {jan} {"Jan."} 2592 | 2593 | MACRO {feb} {"Feb."} 2594 | 2595 | MACRO {mar} {"March"} 2596 | 2597 | MACRO {apr} {"April"} 2598 | 2599 | MACRO {may} {"May"} 2600 | 2601 | MACRO {jun} {"June"} 2602 | 2603 | MACRO {jul} {"July"} 2604 | 2605 | MACRO {aug} {"Aug."} 2606 | 2607 | MACRO {sep} {"Sept."} 2608 | 2609 | MACRO {oct} {"Oct."} 2610 | 2611 | MACRO {nov} {"Nov."} 2612 | 2613 | MACRO {dec} {"Dec."} 2614 | 2615 | 2616 | 2617 | READ 2618 | 2619 | FUNCTION { sortify } 2620 | { 2621 | purify$ 2622 | "l" change.case$ 2623 | } 2624 | 2625 | FUNCTION { chop.word } 2626 | { 2627 | 's := 2628 | 'len := 2629 | s #1 len substring$ = 2630 | { s len #1 + global.max$ substring$ } 2631 | 's 2632 | if$ 2633 | } 2634 | 2635 | FUNCTION { sort.format.names } 2636 | { 2637 | 's := 2638 | #1 'nameptr := 2639 | "" 2640 | s num.names$ 'numnames := 2641 | numnames 'namesleft := 2642 | { namesleft #0 > } 2643 | { nameptr #1 > 2644 | { " " * } 2645 | 'skip$ 2646 | if$ 2647 | s nameptr "{vv{ } }{ll{ }}{ f{ }}{ jj{ }}" format.name$ 't := 2648 | nameptr numnames = t "others" = and 2649 | { " et~al" * } 2650 | { t sortify * } 2651 | if$ 2652 | nameptr #1 + 'nameptr := 2653 | namesleft #1 - 'namesleft := 2654 | } 2655 | while$ 2656 | } 2657 | 2658 | FUNCTION { sort.format.title } 2659 | { 2660 | 't := 2661 | "A " #2 2662 | "An " #3 2663 | "The " #4 t chop.word 2664 | chop.word 2665 | chop.word 2666 | sortify 2667 | #1 global.max$ substring$ 2668 | } 2669 | 2670 | FUNCTION { author.sort } 2671 | { 2672 | author empty.or.unknown 2673 | { key empty.or.unknown 2674 | { "to sort, need author or key in " cite$ * warning$ 2675 | "" } 2676 | { key sortify } 2677 | if$ 2678 | } 2679 | { author sort.format.names } 2680 | if$ 2681 | } 2682 | 2683 | FUNCTION { author.editor.sort } 2684 | { 2685 | author empty.or.unknown 2686 | { 2687 | editor empty.or.unknown 2688 | { 2689 | key empty.or.unknown 2690 | { "to sort, need author, editor, or key in " cite$ * warning$ 2691 | "" 2692 | } 2693 | { key sortify } 2694 | if$ 2695 | } 2696 | { editor sort.format.names } 2697 | if$ 2698 | } 2699 | { author sort.format.names } 2700 | if$ 2701 | } 2702 | 2703 | FUNCTION { editor.organization.sort } 2704 | { 2705 | % added - GNP. Stack editor or organization for sorting (from alpha.bst). 2706 | % Unlike alpha.bst, we need entire names, not abbreviations 2707 | 2708 | editor empty.or.unknown 2709 | { organization empty.or.unknown 2710 | { key empty.or.unknown 2711 | { "to sort, need editor, organization, or key in " cite$ * warning$ 2712 | "" 2713 | } 2714 | { key sortify } 2715 | if$ 2716 | } 2717 | { organization sortify } 2718 | if$ 2719 | } 2720 | { editor sort.format.names } 2721 | if$ 2722 | } 2723 | 2724 | FUNCTION { author.editor.organization.sort } 2725 | { 2726 | % added - GNP. Stack author or organization for sorting (from alpha.bst). 2727 | % Unlike alpha.bst, we need entire names, not abbreviations 2728 | 2729 | author empty.or.unknown 2730 | { 2731 | editor empty.or.unknown 2732 | { organization empty.or.unknown 2733 | { key empty.or.unknown 2734 | { "to sort, need author, editor, or key in " cite$ * warning$ 2735 | "" 2736 | } 2737 | { key sortify } 2738 | if$ 2739 | } 2740 | { organization sortify } 2741 | if$ 2742 | } 2743 | { editor sort.format.names } 2744 | if$ 2745 | } 2746 | { author sort.format.names } 2747 | if$ 2748 | } 2749 | 2750 | FUNCTION { presort } 2751 | { 2752 | % Presort creates the bibentry's label via a call to calc.label, and then 2753 | % sorts the entries based on entry type. Chicago.bst adds support for 2754 | % including organizations as the sort key; the following is stolen from 2755 | % alpha.bst. 2756 | 2757 | calc.label 2758 | basic.label.year 2759 | swap$ 2760 | " " 2761 | swap$ 2762 | * * 2763 | " " 2764 | * 2765 | sortify 2766 | year field.or.null purify$ #-1 #4 substring$ * % add year 2767 | " " 2768 | * 2769 | type$ "book" = 2770 | type$ "inbook" = 2771 | or 2772 | type$ "article" = 2773 | or 2774 | 'author.editor.sort 2775 | { type$ "proceedings" = 2776 | type$ "periodical" = 2777 | or 2778 | 'editor.organization.sort 2779 | { type$ "manual" = 2780 | 'author.editor.organization.sort 2781 | 'author.sort 2782 | if$ 2783 | } 2784 | if$ 2785 | } 2786 | if$ 2787 | #1 entry.max$ substring$ % added for newapa 2788 | 'sort.label := % added for newapa 2789 | sort.label % added for newapa 2790 | * 2791 | " " 2792 | * 2793 | title field.or.null 2794 | sort.format.title 2795 | * 2796 | #1 entry.max$ substring$ 2797 | 'sort.key$ := 2798 | } 2799 | 2800 | 2801 | 2802 | ITERATE { presort } 2803 | 2804 | SORT % by label, year, author/editor, title 2805 | 2806 | % From plainnat.bst 2807 | STRINGS { longest.label } 2808 | 2809 | INTEGERS { longest.label.width number.label } 2810 | 2811 | FUNCTION {initialize.longest.label} 2812 | { "" 'longest.label := 2813 | #0 int.to.chr$ 'last.label := 2814 | "" 'next.extra := 2815 | #0 'longest.label.width := 2816 | #0 'last.extra.num := 2817 | #0 'number.label := 2818 | } 2819 | 2820 | 2821 | 2822 | FUNCTION { initialize.extra.label.stuff } 2823 | { #0 int.to.chr$ 'last.label := 2824 | "" 'next.extra := 2825 | #0 'last.extra.num := 2826 | } 2827 | 2828 | FUNCTION { forward.pass } 2829 | { 2830 | % Pass through all entries, comparing current entry to last one. 2831 | % Need to concatenate year to the stack (done by calc.label) to determine 2832 | % if two entries are the same (see presort) 2833 | 2834 | last.label 2835 | calc.basic.label year field.or.null purify$ #-1 #4 substring$ * % add year 2836 | #1 entry.max$ substring$ = % are they equal? 2837 | { last.extra.num #1 + 'last.extra.num := 2838 | last.extra.num int.to.chr$ 'extra.label := 2839 | } 2840 | { "a" chr.to.int$ 'last.extra.num := 2841 | "" 'extra.label := 2842 | calc.basic.label year field.or.null purify$ #-1 #4 substring$ * % add year 2843 | #1 entry.max$ substring$ 'last.label := % assign to last.label 2844 | } 2845 | if$ 2846 | number.label #1 + 'number.label := 2847 | } 2848 | 2849 | FUNCTION { reverse.pass } 2850 | { 2851 | next.extra "b" = 2852 | { "a" 'extra.label := } 2853 | 'skip$ 2854 | if$ 2855 | label.year extra.label * 'sort.year := 2856 | extra.label 'next.extra := 2857 | } 2858 | 2859 | EXECUTE {initialize.extra.label.stuff} 2860 | EXECUTE {initialize.longest.label} 2861 | 2862 | 2863 | ITERATE {forward.pass} 2864 | 2865 | REVERSE {reverse.pass} 2866 | 2867 | FUNCTION { bib.sort.order } 2868 | { 2869 | sort.label 2870 | " " 2871 | * 2872 | year field.or.null sortify 2873 | * 2874 | " " 2875 | * 2876 | title field.or.null 2877 | sort.format.title 2878 | * 2879 | #1 entry.max$ substring$ 2880 | 'sort.key$ := 2881 | } 2882 | 2883 | ITERATE { bib.sort.order } 2884 | 2885 | SORT % by sort.label, year, title --- giving final bib. order. 2886 | 2887 | FUNCTION { begin.bib } 2888 | { 2889 | %% Set to #0 show 13-digit ISBN in preference to 10-digit ISBN. 2890 | %% Set to #1 to show both 10-digit and 13-digit ISBNs. 2891 | #1 'show-isbn-10-and-13 := 2892 | 2893 | "%%% -*-BibTeX-*-" writeln 2894 | "%%% Do NOT edit. File created by BibTeX with style" writeln 2895 | "%%% ACM-Reference-Format-Journals [18-Jan-2012]." writeln 2896 | "" writeln 2897 | 2898 | preamble$ empty.or.unknown 2899 | 'skip$ 2900 | { preamble$ writeln } 2901 | if$ 2902 | "\begin{thebibliography}{" number.label int.to.str$ * "}" * writeln 2903 | "" writeln 2904 | "%%% ====================================================================" writeln 2905 | "%%% NOTE TO THE USER: you can override these defaults by providing" writeln 2906 | "%%% customized versions of any of these macros before the \bibliography" writeln 2907 | "%%% command. Each of them MUST provide its own final punctuation," writeln 2908 | "%%% except for \shownote{}, \showDOI{}, and \showURL{}. The latter two" writeln 2909 | "%%% do not use final punctuation, in order to avoid confusing it with" writeln 2910 | "%%% the Web address." writeln 2911 | "%%%" writeln 2912 | "%%% To suppress output of a particular field, define its macro to expand" writeln 2913 | "%%% to an empty string, or better, \unskip, like this:" writeln 2914 | "%%%" writeln 2915 | "%%% \newcommand{\showDOI}[1]{\unskip} % LaTeX syntax" writeln 2916 | "%%%" writeln 2917 | "%%% \def \showDOI #1{\unskip} % plain TeX syntax" writeln 2918 | "%%%" writeln 2919 | "%%% ====================================================================" writeln 2920 | "" writeln 2921 | 2922 | %% ACM publications do not use CODEN, ISSN, and LCCN data, so their default 2923 | %% macro wrappers expand to \unskip, discarding their values and unwanted 2924 | %% space. 2925 | %% 2926 | %% For other publications, prior definitions like these may be useful: 2927 | %% 2928 | %% Plain TeX: 2929 | %% \def \showCODEN #1{CODEN #1.} 2930 | %% \def \showISSN #1{ISSN #1.} 2931 | %% \def \showLCCN #1{LCCN #1.} 2932 | %% 2933 | %% LaTeX: 2934 | %% \newcommand{\showCODEN}[1]{CODEN #1.} 2935 | %% \newcommand{\showISSN}[1]#1{ISSN #1.} 2936 | %% \newcommand{\showLCCN}[1]{LCCN #1.} 2937 | 2938 | "\ifx \showCODEN \undefined \def \showCODEN #1{\unskip} \fi" writeln 2939 | "\ifx \showDOI \undefined \def \showDOI #1{#1}\fi" writeln 2940 | % ACM styles omit ISBNs, but they can be included by suitable definitions of 2941 | % \showISBNx and \showISBNxiii before the .bbl file is read 2942 | "\ifx \showISBNx \undefined \def \showISBNx #1{\unskip} \fi" writeln 2943 | "\ifx \showISBNxiii \undefined \def \showISBNxiii #1{\unskip} \fi" writeln 2944 | "\ifx \showISSN \undefined \def \showISSN #1{\unskip} \fi" writeln 2945 | "\ifx \showLCCN \undefined \def \showLCCN #1{\unskip} \fi" writeln 2946 | "\ifx \shownote \undefined \def \shownote #1{#1} \fi" writeln % NB: final period supplied by add.period$ above 2947 | "\ifx \showarticletitle \undefined \def \showarticletitle #1{#1} \fi" writeln 2948 | "\ifx \showURL \undefined \def \showURL {\relax} \fi" writeln 2949 | "% The following commands are used for tagged output and should be " writeln 2950 | "% invisible to TeX" writeln 2951 | "\providecommand\bibfield[2]{#2}" writeln 2952 | "\providecommand\bibinfo[2]{#2}" writeln 2953 | "\providecommand\natexlab[1]{#1}" writeln 2954 | "\providecommand\showeprint[2][]{arXiv:#2}" writeln 2955 | } 2956 | 2957 | EXECUTE {begin.bib} 2958 | 2959 | EXECUTE {init.state.consts} 2960 | 2961 | ITERATE {call.type$} 2962 | 2963 | FUNCTION { end.bib } 2964 | { 2965 | newline$ 2966 | "\end{thebibliography}" 2967 | writeln 2968 | } 2969 | 2970 | EXECUTE {end.bib} 2971 | -------------------------------------------------------------------------------- /reference document/Avail Reference Paper v2 17 Sept 2024.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/availproject/data-availability/1fa5e8b1260344b137b17a3dfa1e493a14b5888a/reference document/Avail Reference Paper v2 17 Sept 2024.pdf -------------------------------------------------------------------------------- /reference document/Avail Reference Paper v2.1 6 Nov 2024.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/availproject/data-availability/1fa5e8b1260344b137b17a3dfa1e493a14b5888a/reference document/Avail Reference Paper v2.1 6 Nov 2024.pdf -------------------------------------------------------------------------------- /reference document/DA-KC-Data.drawio: -------------------------------------------------------------------------------- 1 | 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2020)" 12 | } 13 | @manual{polkadot_consensus:2020, 14 | title = "Polkadot Consensus", 15 | author = "Polkadot", 16 | url = "https://wiki.polkadot.network/docs/en/learn-consensus", 17 | year = "2020 (accessed December 18, 2020)" 18 | } 19 | @misc{grandpa, 20 | title={GRANDPA: a Byzantine Finality Gadget}, 21 | author={Alistair Stewart and Eleftherios Kokoris-Kogia}, 22 | year={2020}, 23 | eprint={2007.01560}, 24 | archivePrefix={arXiv}, 25 | primaryClass={cs.DC} 26 | } 27 | @manual{StarkEx:2020, 28 | title = "zkRollup vs. Validium", 29 | author = "Alex Gluchowski", 30 | url = "https://medium.com/matter-labs/zkrollup-vs-validium-starkex-5614e38bc263", 31 | year = "2020 (accessed November 24, 2020)" 32 | } 33 | @manual{dankrad_poly:2019, 34 | title = "An alternative low-degreeness proof using polynomial commitment schemes", 35 | author = "Dankrad Feist", 36 | url = "https://ethresear.ch/t/an-alternative-low-degreeness-proof-using-polynomial-commitment-schemes/6649", 37 | year = "2019 (accessed November 24, 2020)" 38 | } 39 | @manual{EthResearch_DA:2020, 40 | title = "2D data availability with Kate commitments", 41 | author = "Vitalik Buterin", 42 | url = "https://ethresear.ch/t/2d-data-availability-with-kate-commitments/8081", 43 | year = "2020 (accessed November 24, 2020)" 44 | } 45 | @manual{EthWiki:2018, 46 | title = "A note on data availability and erasure coding", 47 | author = "Vitalik Buterin", 48 | url = "https://github.com/ethereum/research/wiki/A-note-on-data-availability-and-erasure-coding", 49 | year = "2018 (accessed November 24, 2020)" 50 | } 51 | @misc{albassam2019fraud, 52 | title={Fraud and Data Availability Proofs: Maximising Light Client Security and Scaling Blockchains with Dishonest Majorities}, 53 | author={Mustafa Al-Bassam and Alberto Sonnino and Vitalik Buterin}, 54 | year={2019}, 55 | eprint={1809.09044}, 56 | archivePrefix={arXiv}, 57 | primaryClass={cs.CR} 58 | } 59 | @misc{yu2019coded, 60 | title={Coded Merkle Tree: Solving Data Availability Attacks in Blockchains}, 61 | author={Mingchao Yu and Saeid Sahraei and Songze Li and Salman Avestimehr and Sreeram Kannan and Pramod Viswanath}, 62 | year={2019}, 63 | eprint={1910.01247}, 64 | archivePrefix={arXiv}, 65 | primaryClass={cs.CR} 66 | } 67 | @InProceedings{Kate:2010, 68 | author="Kate, Aniket 69 | and Zaverucha, Gregory M. 70 | and Goldberg, Ian", 71 | editor="Abe, Masayuki", 72 | title="Constant-Size Commitments to Polynomials and Their Applications", 73 | booktitle="Advances in Cryptology - ASIACRYPT 2010", 74 | year="2010", 75 | publisher="Springer Berlin Heidelberg", 76 | address="Berlin, Heidelberg", 77 | pages="177--194", 78 | isbn="978-3-642-17373-8" 79 | } 80 | @misc{lazyledger, 81 | title={LazyLedger: A Distributed Data Availability Ledger With Client-Side Smart Contracts}, 82 | author={Mustafa Al-Bassam}, 83 | year={2019}, 84 | eprint={1905.09274}, 85 | archivePrefix={arXiv}, 86 | primaryClass={cs.CR} 87 | } -------------------------------------------------------------------------------- /reference document/Data Availability - Reference Document.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/availproject/data-availability/1fa5e8b1260344b137b17a3dfa1e493a14b5888a/reference document/Data Availability - Reference Document.pdf -------------------------------------------------------------------------------- /reference document/Data Availability - Reference Document.tex: -------------------------------------------------------------------------------- 1 | \documentclass[sigconf, screen=true, nonacm]{acmart} 2 | 3 | \usepackage{todonotes} 4 | \setuptodonotes{size=\tiny} 5 | 6 | \settopmatter{printacmref=false} 7 | \setcopyright{none} 8 | \renewcommand\footnotetextcopyrightpermission[1]{} 9 | 10 | \hypersetup{pdftitle={Avail - Data Availability}} 11 | 12 | \newcommand{\DA}{\textit{DA layer}} 13 | \newcommand{\EX}{\textit{Exec layer}} 14 | \newcommand{\DR}{\textit{DR layer}} 15 | 16 | \begin{document} 17 | 18 | \title{Avail: The Data Availability Blockchain} 19 | \author{Avail \vspace{1cm}} 20 | 21 | \begin{abstract} 22 | % We discuss a blockchain design where the data hosting and availability, contract execution and dispute resolution is decoupled. We further propose the details of the data layer which guarantees availability. 23 | We study the scalability issue in present blockchain architecture and propose a design which decouples the data hosting, execution and verification. We discuss few suitable primitives for the construction of a data hosting layer that guarantees data availability. We sketch out the system goals, design, security and implementation details of Avail which is our availability focussed blockchain solution. 24 | \end{abstract} 25 | 26 | \maketitle 27 | 28 | 29 | \section{Present DApp Architecture} 30 | In present day Ethereum-like ecosystems, there are mainly three types of peers - validator nodes, full nodes and light clients. A block is appended to the blockchain by a validator node which collects transactions from the mempool, executes them, generates the block before propagating it across the network. The block contains a small block header containing digest and metadata related to the transactions included in the block. The full nodes across the network receive this block and verify its correctness by re-executing the transactions. The light clients only fetch the block header and fetch transaction details from neighbouring full nodes on an as-needed basis. The metadata inside the block header enables the light client to verify the authenticity of the received transactional details. 31 | 32 | While this architecture is extremely secure and has been widely adopted, it has some serious practical limitations~\cite{Stanford:2020}. Because every transaction is executed by all the full nodes in the system, it becomes a bottleneck resulting in limited throughput. With wide adoption of such DApps, the number of transactions grow rapidly resulting in increased cost of including a transaction into a block. To counter these issues, layer 2 solutions have been proposed. 33 | 34 | Layer 2 scaling solutions work by creating a chain anchored to the main chain like Ethereum. In such an architecture, DApps reside on the L2 chain and only periodic checkpoints are recorded on the main chain. The throughput in such a system depends on the transaction processing rate of the L2 chain whereas any dispute resolution can be performed on the main chain. The benefit of such a decoupled execution and dispute resolution is that it gives much higher throughput while retaining the security properties. In practice, multiple such L2 chains may function in parallel resulting in improved processing power of the system, while retaining the security of the main chain. 35 | 36 | \section{Plasma, Optimistic Rollup and ZK Rollup}\label{rollup} 37 | A major part of a successful layer 2 solution is the execution and verification framework. Plasma based sidechain approach can process thousands of transactions and submit only a single hash as checkpoint to the main chain. However, it faces an important issue. In case of a dispute on the sidechain, Plasma lacks an efficient mechanisms for users to exit the sidechain. Also, Plasma lacks the ability to process arbitrary instructions although they are supported by a quasi Turing-complete main chain like Ethereum. 38 | 39 | Optimistic Rollups like Arbitrum and Optimism use the optimistic execution paradigm where a manager/operator executes the sidechain transactions and submits an assertion on the main chain. In case of dispute, other participants can challenge the assertion on chain within a fixed timeout and then the main chain performs the dispute resolution. While this scales up the transaction processing rate, it has a few downsides like delayed finality for non-fungible assets among others. 40 | 41 | Zero-knowledge based rollups like Polygon zkEVM and Starkware take the ZK based approach to off-chain execution. The operators execute the transactions and submit a ZK proof to the main chain. The main chain can quickly verify the proof and on-chain participants can be assured that only valid state transitions were performed. 42 | 43 | Another class of rollup is Validium which is a hybrid between Plasma and ZK based rollups. They make use of Zero-knowledge based proofs of execution and at the same time keep the transactional data off-chain. Although this improves the throughput of the system, they suffer similar problems to that of Plasma. User funds can be frozen or seized and other crypto-economic attacks are also possible on such a system. \cite{StarkEx:2020} provides a detailed discussion on the approach and possible attacks. 44 | 45 | While there is still debate inside the community about which of these approaches is the best, we envision multiple such roll-ups operating simultaneously together forming the execution layer of our design. 46 | 47 | \section{The Data Availability Problem} 48 | While the off-chain execution based architecture improves throughput, it is still limited by the amount of data that the main chain like Ethereum can handle. This is because although the execution is off-chain, the verification or dispute resolution is strictly on-chain. The transactional data is submitted as calldata on Ethereum to ensure that the data is available for future reconstruction. This is extremely important. In case of optimistic rollups, the operator may submit invalid transactions and then suppress parts of the block to the world. This way, the other full nodes in the system will not be able to verify whether the submitted assertion is correct. Due to lack of data, they will not be able to produce any fraud proof/challenge to show that the assertion is indeed invalid. In case of Zero-knowledge based rollups, the ZKP soundness ensures that accepted transactions are valid. However, even in the presence of such guarantees, not revealing the data backing a transaction can have serious side effects. It may lead to other validators not being able to calculate the current state of the system. \cite{EthWiki:2018} contains a detailed discussion on the subject. 49 | 50 | We recognize that to achieve higher throughput, we not only need to put execution off-chain but also need to have a scalable data hosting layer that guarantees data availability. In later sections we discuss a design of such a decentralized Data Availability layer. 51 | 52 | \section{System Overview} 53 | \subsection{Decoupling the components} 54 | On a high level, a successful blockchain design needs to address the following components: 55 | \begin{itemize} 56 | \item \textbf{Data Hosting and Ordering:} This component would receive transactional data and order it without any execution. It would then store the data and ensure complete data availability in a decentralized manner. We call this component the \DA. 57 | \item \textbf{Execution:} The execution component should take ordered transactions from the \DA{} and execute them. It should create a checkpoint/assertion/proof and submit it to the \DR. We call this the \EX. 58 | \item \textbf{Verification/Dispute Resolution:} This component represents the settlement layer to which the system is anchored. The security of the design is dependent on the robustness and security properties of this component along with the \DA. The checkpoint or assertion or proof submitted by \EX{} is processed by this layer to guarantee that only valid state transitions are accepted in the system (provided that the data is available). We refer to this component as the \DR. 59 | \end{itemize} 60 | 61 | In this work, we are proposing Avail, which acts as the \DA. We envision the multiple roll-up initiatives or legacy execution layers to form the \EX. The \DR{} can be any secure settlement layer which supports the execution verification. 62 | 63 | \subsection{Participants and System Goals} 64 | \subsubsection{Types of Nodes} 65 | We consider the following types of nodes for Avail: 66 | \begin{itemize} 67 | \item \textbf{Full Nodes:} The full nodes download the blocks and validate their correctness but do not participate in consensus. They store the blockchain but are not incentivized to participate or remain honest. 68 | \item \textbf{Validator Nodes:} The validator nodes take part in block generation and decide on transaction inclusion and ordering. These nodes are incentivized to participate in consensus and host the blockchain. Essentially, they are also full nodes with stake in the system. 69 | \item \textbf{Light Clients:} These are clients with resource constraints who have access to only the block header and query transactional data from other full nodes on an as-needed basis. They want to have high confidence that the block is available, and when querying data they want a proof that the data belongs to the block. 70 | \end{itemize} 71 | % We assume that the nodes are part of a peer-to-peer network with the light client connected to at least one honest full node. We have two types of adversaries in our system: 72 | % \begin{enumerate} 73 | % \item \textbf{Ordering Attacker:} This type of adversary wants to disrupt the decentralized data hosting layer by either not allowing the blockchain to grow or by trying the network to accept two contradictory blocks. As our blockchain does not enforce any transactional logic but only enforces a strict ordering, the adversary of this type want to make the network accept two blocks with different orderings. We assume that at most $\frac{1}{3}$ of validators can be controlled by this adversary. 74 | % \item \textbf{Data Availability Attacker:} The DA attacker wants to hide a small portion of the data present inside a block and wants the network to accept such a block. We assume that majority of full nodes can go rogue and be controlled by this type of an adversary, but there is at least one honest full node with the entire data. We note that the DA attacker can target data present in any block and not just the most recent block. In particular, we want the \DA{} to be resistant against such an attacker for historical data as well. 75 | % \end{enumerate} 76 | \subsubsection{System Goals}\label{goals} 77 | Our design for Avail should provide the following guarantees: 78 | \begin{enumerate} 79 | \item \label{goal:one} The decentralized data availability blockchain keeps producing a canonical chain of blocks even in the presence of an adversary that controls $<\!\!\frac{1}{3}$ of the validator nodes in the network. 80 | \item \label{goal:two} The honest participants of the system with access to the canonical chain of block headers will not accept a block whose underlying data is unavailable even if a very powerful adversary is controlling all the other nodes in the system. Under the assumption that there are enough honest participants, the data should remain available for a limited amount of time. 81 | \end{enumerate} 82 | We want to guarantee achieving both these system goals. We want to emphasize that both the goals have different adversarial assumptions. Goal \ref{goal:one} ensures that the blockchain system continues to function in a decentralized manner as long as a super-majority of validator nodes remain honest. Goal \ref{goal:two} ensures that an outside participant like an application running a light node, who has access to the canonical chain of block headers, need not trust any full node to have the guarantee that the underlying data for a particular block is available. This is an extremely strong assumption which eliminates any trust assumption to detect data hiding attempt. In the next sections we discuss our construction ideas and argue that they achieve these goals. 83 | 84 | \section{Designing the Data Availability Layer} 85 | \subsection{Primitives} 86 | % Hash Function. Erasure Coding. Kate Commitment. \todo{expand} 87 | \subsubsection{Why is redundancy important in ensuring Data Availability?} 88 | Suppose we have a block $B$ divided into data chunks $D_1, \dots, D_n$. The block producer wants to suppress one chunk. Without loss of generality, let us assume that the first chunk is hidden by the block producer. Clients can query one chunk at random to get guarantees that data is indeed available. It can repeat this process many times so as to get sufficient confidence that the data is accessible. Hence, for each query, the block producer needs to be lucky enough that $D_1$ is not queried. 89 | 90 | However, with redundancy included by schemes like erasure coding, suppose the $n$ chunks are encoded into $2n$ chunks. Erasure coding ensures that any $n$ out of the $2n$ chunks are sufficient to recreate the data. This makes the hiding task harder for the block producer. To hide one particular chunk, it needs to make at least $n+1$ chunks unavailable. As a client, querying constant number of times gives a very high confidence that the data is indeed available. Hence, redundancy plays a vital role in the data availability. An erasure coding based design along with the related tradeoffs are discussed in \cite{albassam2019fraud}. 91 | 92 | \subsubsection{Fraud Proofs} 93 | In the previous section although we discussed the advantage of redundancy in data, we omitted the case when the erasure coded chunks are misconstructed by the block producer. In these cases, even though most chunks are indeed available, the entire block data might not be accessible. Hence, fraud proofs are constructed by other full nodes in the system and propagated to the light nodes. The light nodes verify the fraud proof and get convinced that the received block header is that of an erroneous block. An interesting property of fraud proofs is that they function even under a minority honest assumption. This is because having a single honest full node as a neighbour is sufficient for an honest light node to be guaranteed that it receives the fraud proof. 94 | 95 | An important factor to consider during design of \DA{} is the size of fraud proofs. In simple erasure coded chunks, to proof that the encoding is incorrect, the entire original data block needs to be propagated to the light client. Hence, the fraud proof size is at least linear to the size of the block. Although we do not discuss the higher dimensional erasure coding based design here, we refer to \cite{albassam2019fraud} for a detailed analysis of fraud proof sizes. 96 | 97 | \subsubsection{Commitment Size} 98 | In a one dimensional erasure coding based design, once a block producer selects data chunks $D_1, \dots, D_n$, it encodes the chunks to generate $D_1, \dots, D_{2n}$ (assuming coding rate to be $0.5$). It then constructs a Merkle tree over the chunks and keeps the root of it in the block header which acts as the commitment. A light client fetching $D_i$ gets a Merkle membership proof along with the data chunk so that it can quickly verify that a legitimate chunk has been supplied. The commitment (root of Merkle tree) size is an important factor to consider in any design. With large commitments, block headers become larger resulting in increased network traffic. While higher dimensional erasure coding based schemes achieve shorter fraud proof size, it comes at the cost of larger commitments. 99 | 100 | \subsection{Coded Merkle Tree based Design} 101 | We briefly discuss the Coded Merkle Tree (CMT) based approach~\cite{yu2019coded} proposed by Yu \textit{et al.} The novelty of this approach is that it gives constant sized commitments with logarithmic sized fraud proofs. 102 | 103 | The design uses systematic erasure codes at each layer of the Merkle tree. In particular, at the base layer, it takes $k$ data chunks and extends it to $n$ data chunks in such a manner that the first $k$ out of $n$ chunks are the original chunks and the rest are parity symbols. Each chunk in the next layer of the tree is made from hashes of $q$ chunks of the previous layer. Similar systematic erasure code is applied on that layer as well and we keep building successive levels of the tree until we have $t$ hashes which we keep as the commitment inside the block header. 104 | 105 | When a light node samples a base layer chunk, the chunk along with a Merkle membership proof is given in such a manner that not only availability of base layer is ensured but also the higher layer availability is guaranteed. A light client sampling $s$ base layer chunks the Merkle membership proof will automatically sample $s$ intermediate layer chunks with high probability. 106 | 107 | For a full client, decoding the tree and generation of fraud proof is also extremely efficient. With access to the root layer of the CMT present in the header and some coded chunks of the previous layer, the hash-aware peeling decoder decodes the previous layer getting access to all the hashes of the preceding layer. The decoder continues until all the chunks in the base layer is decoded or it finds evidence of an incorrect coding. In case of the former, the full node gets access to the entire data and in case of the latter, it generates the fraud proof and broadcasts it. 108 | 109 | A detailed description of the construction along with performance analysis is present in \cite{yu2019coded}. 110 | 111 | \subsection{Kate Commitment based Design} 112 | In this section we first discuss polynomial commitments proposed by Kate \textit{et al.}~\cite{Kate:2010}. Then we go on to discuss a \DA{} design based on Kate commitments as proposed in \cite{EthResearch_DA:2020}. 113 | 114 | Given a polynomial $\phi(x) \in \mathbb{Z}_p[x]$ over a bilinear pairing group, Kate \textit{et al.} proposed a scheme to have a commitment to the polynomial using a single group element. Moreover, the scheme supports opening of a commitment at a point $i$ to get $\phi(i)$ using constant sized witness that allows a verifier to confirm that $\phi(x)$ was indeed evaluated at $i$ to get $\phi(i)$. The commitment scheme is both computationally hiding and binding. The commitment scheme is additively homomorphic and supports a single witness for a batch of openings on multiple points of the same polynomial. 115 | 116 | Given such a scheme, the block producer breaks the block data into chunks such that each chunk is an element of the field. It arranges the chunks into n rows and m columns such that it forms an $n \times m$ matrix $D$. It uses the evaluation form to construct a polynomial from each row to obtain $\phi_1(x), \dots, \phi_n(x)$. It then commits each polynomial to get $C_1, \dots, C_n$ respectively. For redundancy, it extends $C_1, \dots, C_n$ to $C_1, \dots, C_{2n}$. It puts $C_1, \dots, C_{2n}$ inside the block header and broadcasts it. Figure \ref{fig:KC_data} shows the data arrangement and the corresponding commitments. 117 | 118 | \begin{figure}[h] 119 | \centering 120 | \includegraphics[width=\linewidth]{DA-KC-Data.png} 121 | \caption{Data Arrangement in Kate Commitment based \DA} 122 | \label{fig:KC_data} 123 | \end{figure} 124 | 125 | The light clients querying a data block will sample some chunk $D[i][j]$. Along with the data, the light client gets a witness $w[i][j]$ and it can immediately verify the validity using the Kate Commitment scheme discussed above. If it queries multiple chunks of the same row, the batch commitment scheme helps have a single witness for all the sampled points. Hence the membership proofs are extremely efficient. 126 | 127 | For full nodes, the system can have two types of full nodes: 1. classical full nodes having entire block, 2. Column full nodes which keep only a single column of the data. For classical ones, it takes the entire matrix $D$, extends each column to $2n$ points and getting an extended matrix $D'$. 128 | 129 | It then verifies for each row of $D'$ whether the commitment to $i^{th}$ row is $C_i$ for $1 \leq i \leq 2n$. 130 | 131 | For the column full nodes, they can fetch and keep only a column of the matrix $D$. They would extend each column to check whether they belong to the extended set of commitments. This is possible because of the homomorphic nature of the commitments and witnesses. In particular, having $D[1][j], \dots,\allowbreak D[n][j]$ and $w[1][j],\allowbreak \dots, w[n][j]$, the node can extend both to $2n$ points and immediately verify whether the extended openings are valid. If the number of such column full node is $O(m)$, and each column full node ensures at least one column is available, then collaboratively the entire data is available within the column full nodes. 132 | 133 | As the block size grows, so does the number of commitments (keeping number of columns fixed, the number of rows grow). Hence the commitment size grows linear to that of the block size. However, we do not need any fraud proofs in such a system. For each light client, the communication and computational overhead is constant. For each full node, the computational overhead is $O(m*n log(n))$ as it needs to perform $O(m)$ FFTs, $O(1)$ for each column, along with some pairing checks for verification. However, a column node has to only perform $O(n log(n))$ work because it works on a single column of data. 134 | 135 | 136 | \section{Analysis} 137 | \subsection{Attack Vectors} 138 | Any \DA{} needs to counter the following attacks on data availability: 139 | \begin{enumerate} 140 | \item \label{attack:ordering} A super-majority of the validators in the \DA{} wants to change the ordering of an already finalized block. 141 | \item \label{attack:wrong} A super-majority of the validators create a wrong block header, i.e., the commitment of the data present in the header is wrong. 142 | \item \label{attack:hide} A super-majority of the validators want to hide at least one chunk of the block. For a light node, this would mean not being able to detect hiding of data with a non-negligible probability. For a full node, this would mean not being able to reconstruct the data. 143 | \end{enumerate} 144 | 145 | We take the case of the super-majority of validators attacking the \DA{} because we want to minimize honesty assumption required for our design. 146 | 147 | Under the assumption that finality is reached, the reordering attack (attack \ref{attack:ordering}) is hard to mount. This is because, to successfully mount this attack the attacker would need to break the non-equivocation property of the underlying consensus. In particular, the finality layer ensures that if equivocation occurs, the dishonest parties can be identified and their stake slashed. 148 | 149 | In the subsequent sections we show how Attack \ref{attack:wrong} and Attack \ref{attack:hide} is countered in each of the two design choices - CMT and Kate Commitments. 150 | 151 | \subsection{Coded Merkle Trees} 152 | In the CMT based approach, the block proposer(s) may attempt to construct wrong header in two ways: 153 | \begin{itemize} 154 | \item The erasure coding in one or more layers is wrong. 155 | \item The Merkle tree construction is wrong. 156 | \end{itemize} 157 | 158 | In both cases, the fraud proof captures such an attack. A full node, with access to the data, can build the incorrect-coding proof and broadcast it for the light clients. \cite{yu2019coded} contains a detailed description of such a fraud proof. 159 | 160 | The random sampling from base layer by a light client also samples higher layers. As each layer is erasure coded, hence, probability of hiding any chunk from any of the layers of the Merkle tree is extremely low for sufficiently many samplings. A full client who wants to reconstruct the Merkle tree needs access to the block header which contains the root hashes. Along with that, it needs $(1-\alpha)n$ samples of the each layer, where $n$ is the total chunks in the layer and $\alpha$ is the minimum fraction of coded symbols a malicious block producer needs to make unavailable to prevent full decoding. With these information it can decode the entire tree. The entire decoding strategy along with the hash-aware peeling decoder construction is given in \cite{yu2019coded}. 161 | 162 | Hence, the CMT approach can mitigate both attack \ref{attack:wrong} and \ref{attack:hide}. We however note that the mitigation assumes a single honest full node, which is not as strong as Goal \ref{goal:two} defined in Section \ref{goals}. 163 | 164 | \subsection{Kate Commitments} 165 | In the Kate commitment based approach, attack \ref{attack:wrong} amounts to a wrong commitment by the block producer. Without loss of generality, suppose $C_1$ is wrong. This would mean that at least one out of $D[1][1]$ to $D[1][n]$ does not belong to $C_1$. Again, let us assume $D[1][1] \not\in C_1$. This would mean that at least one of this is true: $D[n+1][1] \not\in C_{n+1}, \dots, D[2n][1] \not\in C_{2n}$. This is because $C_{n+1}, \dots, C_{2n}$ are extended from $C_1, \dots, C_n$ and $D[n+1][1], \dots, D[2n][1]$ are extended from $D[1][1], \dots, D[n][1]$. Hence, such an attack is caught by a light client with overwhelming probability. 166 | 167 | In case of attack \ref{attack:hide}, a light client querying constant samples can achieve arbitrarily high confidence that the data is indeed available. This is due to the redundancy in the data as discussed previously. For a full node, it needs to download the at least $n$ chunks from each column so that it can reconstruct the entire extended data. It checks the commitments to know whether the downloaded data is correct. A column full node needs to perform similar operations but only for one column of data. Even if the supermajority wants to suppress data after some time, the light client P2P layer contains the data with redundancy. This enables new clients to recover block data without reliance on the full nodes or validators. 168 | 169 | Hence, this approach mitigates all discussed attacks and achieves the goals set in Section \ref{goals}. 170 | 171 | \section{Implementation} 172 | In this section, we discuss the implementation details of Avail. Among the two techniques discussed above, we use the Kate commitment based approach in order to avoid fraud proofs and provide strong data availability guarantees even in presence of powerful adversaries. 173 | 174 | \subsection{Consensus} 175 | We need our validators to reach consensus on the next block which contains the ordered set of transactions along with redundant erasure coded data. 176 | % To achieve that, we use a consensus protocol that satisfies the following: 177 | % \begin{itemize} 178 | % \item \textbf{Safety:} No two honest nodes have finalized chain of blocks with two conflicting blocks. In our context, this means that all honest nodes agree on a unique ordering of transactions. 179 | % \item \textbf{Liveness:} Irrespective of previous events, new blocks can always be added to the chain and finalized. In our context, this ensures that new transactions are always added in the chain. 180 | % \end{itemize} 181 | Although there exists many possible blockchain consensus protocols, we opted for the Proof-of-Stake (PoS) family of consensus algorithms. We wanted a PoS consensus that supports high number of validators, provable finality and a robust security framework. In particular, we chose the BABE/GRANDPA hybrid consensus used by Polkadot~\cite{polkadot_consensus:2020}. It uses two separate protocols for block production and finality. 182 | 183 | The block production is done using Blind Assignment for Blockchain Extension protocol (BABE)~\cite{BABE:2020}. The block producers produce blocks based on a Verifiable Random Function (VRF). The protocol does not assume access to a central clock. In case no validator is chosen as the block producer for a particular slot, or if the chosen producer(s) go down, there is a secondary block producer who can step in. BABE ensures liveness which guarantees that transactions submitted to honest players will eventually be inserted into the chain. 184 | 185 | GRANDPA (GHOST-based Recursive ANcestor Deriving Prefix Agreement)~\cite{grandpa} is a finality gadget ensuring provable finality. Without the finality gadget, the users can only have probabilistic finality, like in classical blockchain systems. GRANDPA guarantees that blocks reach quicker finality and a finalized block can never be reverted. 186 | 187 | \subsection{Full Nodes} 188 | To implement our design in a standalone blockchain, we use the Substrate framework~\footnote{https://github.com/paritytech/substrate}. Substrate provides great flexibility to implement custom runtime logic with inherent BABE/GRANDPA consensus support. Our design needed major changes in the Substrate codebase and hence we worked on a separate codebase~\footnote{https://github.com/availproject/avail}. The major changes that we made are: 189 | \begin{itemize} 190 | \item The contents of the block are arranged into the data matrix, extended and polynomial commitment generation is performed during the block building process. 191 | \item The header structure is changed to contain the commitments as part of the header. 192 | \item Block sizes are made dynamic, according to the number of transactions on the mempool. However, the maximum block size allowed is 4 MB, including the data redundancy. 193 | \item Additional RPC methods to support data availability queries are introduced. These can be used by light clients to gain confidence about availability and inclusion. 194 | \end{itemize} 195 | We have modified the Polkadot Apps~\footnote{https://github.com/availproject/avail-apps} to build our block explorer~\footnote{https://testnet.avail.tools/} for our test network. 196 | 197 | \subsection{Light Client} 198 | In our present design, light clients are nodes that participate in the system without investing resources to host a full node. We want our light clients to have very high data availability guarantees without hosting a full node or trusting on any other peer. Keeping this in mind, we have developed a light client~\footnote{https://github.com/availproject/avail-light} which keeps track of the chain header and performs availability queries to gain confidence on the availability of interested blocks. They also help contribute to data availability by hosting sampled data for other light clients within the P2P network. The client can gain as high confidence as deemed suitable for the specific application. We envisage the applications using our chain to host a light client. 199 | 200 | \subsection{Ethereum Data Availability Guarantees} 201 | A \DR{} layer like Ethereum, when validating proofs or resolving dispute, need assurance that the underlying data is indeed available (as discussed in Sec \ref{rollup}). To enable this in an organic manner, we want to guarantee data availability to a smart contract on Ethereum (or any settlement layer which supports this logic). This allows the checkpoint/assertion/proof accepting smart contract to communicate with this light client contract and directly get DA assurance. 202 | 203 | We discuss three main approaches on how to provide the on-chain DA guarantee. We also briefly mention their advantages and limitations. 204 | 205 | % \subsubsection{Light Client as a Smart Contract} 206 | % The most obvious approach to achieve DA guarantee is to host the conventional light client as a smart contract. This provides the same guarantees on-chain as the off-chain light client. However, there are three main challenges to this approach: 207 | % \begin{itemize} 208 | % \item The smart contract needs a continuous feed of Avail chain headers. The primary concern is who submits these headers, how do we verify the submitted headers and how do we compensate the cost these submitting parties incur. We can take ideas from existing cross-chain bridging solutions to address these concerns. 209 | % \item The DA guarantee is highly dependent on the randomness of the queries. Smart contracts, on the other hand, can only run deterministic programs. We may use solutions like RANDAO~\footnote{https://github.com/randao/randao} to eliminate this bottleneck. 210 | % \item Even if the header is available to the contract, query is generated randomly and proof is submitted, the smart contract still needs to verify the responses to get confidence that the data is available. On-chain Kate commitment verification is challenging without supporting opcode for field operations. We could propose new pre-compiled contracts to support them but implementation requires consensus within the community and a hard fork. 211 | % \end{itemize} 212 | 213 | \subsubsection{Data Availability Oracle} 214 | A widely accepted approach for off-loading expensive tasks from smart contracts is the oracle based approach. When on-chain DA guarantee for a particular block is needed, multiple oracle nodes can be incentivized to submit their respective confidence factors. The on-chain contract can aggregate the metrics to decide whether it has sufficient guarantee that the data is available. Although well-accepted within the community, this approach has to trust the oracle nodes resulting in reduced security guarantees. The amount of trust can be limited by proper incentivization and decentralization. 215 | 216 | \textbf{Proof of Concept Implementation}: To emphasize the viability of the protocol, we have implemented an on-chain light client using Chainlink Oracle Network, based on the second design discussed above. Whenever the on-chain contract needs availability guarantee for a particular block, it requests the on-chain Chainlink Oracle which uses events to communicate with multiple off-chain oracle nodes. These off-chain nodes use their own light clients or hosted instances to gain confidence and communicate the same back to the original contract through the Chainlink Oracle. The incentivization is handled using the LINK token. 217 | 218 | \subsubsection{Bridges} 219 | A well-known approach for cross-chain message passing is using bridges. Using a bridge from Avail to \DR, the validators of Avail can attest to the fact that a particular piece of data is available. The downside of such approach is that it relies on the supermajority of the Avail validator set to be honest and to keep the data available. For most applications, this is a good enough assumption. 220 | 221 | Under this model, the rollup operator submits the data on Avail and gets back a finalized block post transaction inclusion. It computes a proof of transaction inclusion within that block and posts it, along with proof of transactional validity, to the settlement rollup contract. The bridge operator(s), on the other hand, post finalized block metadata on the settlement layer. The rollup contract, upon receiving the proofs, checks the correctness of proofs against the bridge contract. The rollup transaction is accepted iff the proofs are verified to be correct. 222 | 223 | % \subsubsection{Non-interactive DA proofs} 224 | % The light client construction and security guarantees are based on an interactive protocol where the client queries to full nodes to get proofs which they verify to gain confidence on the availability. We need to explore making the protocol non-interactive where the light clients can subscribe to availability proofs without compromising the security. However, the guarantee that the data is available now does not enforce its availability in the future. We need to carefully design the protocol keeping security, efficiency and practicality in mind. 225 | 226 | 227 | \section{Additional Modules} 228 | \subsection{Application Specific Data Retrieval} 229 | We would want our construction to allow applications to download data which is only relevant to them. To enable this, we want the full nodes to prove to an application client that the complete set of data relevant to the application has been communicated. 230 | 231 | To enable Application Specific Data Retrieval (ASDR), we have introduced two main fields: 232 | \begin{itemize} 233 | \item \textbf{AppID}: Every transaction has been associated with an application identifier (appID). We envision rollup or application specific chains to register as applications if they want to download parts of block with only relevant application data. Any user is free to use the default appID `0' which is used for all types of transaction, including Avail system transactions. Any transaction with nonzero appID has to be of type application data submission only. 234 | \item \textbf{appDataLookup}: Every block header contains an index field, containing the starting cell indices of application cells inside the block. This is created by the block producer when creating the block by grouping the data matrix by appID and then flattening it to infer the starting position of each group. 235 | \end{itemize} 236 | 237 | The changes above together ensure that an application client can download only app-specific cells without downloading other application data. 238 | 239 | However, it is worth noting that there is no reliance on the block producer to create the index or group the data correctly. This is because, we create a deterministic algorithm that all honest application clients follow. Hence, all honest clients would retrieve the same app data for a particular appID. It can happen that clients get partial data, i.e., there exists data within the block associated with an appID which was not downloaded following the algorithm. However, the aim is to have the same view of their app to all honest app clients by providing them with same data. The polynomial commitments inside header assure that two clients with access to the same header cannot receive different sets of data. 240 | 241 | % To illustrate, let us assume a roll-up \textit{R} operates on our proposed \DA. Hence, it would want to download only transactions which are intended for \textit{R}. 242 | 243 | % For the CMT based approach, we can use a Namespaced Merkle Tree as described in \cite{lazyledger}. We would need to make some alterations to the original construction to make it work with the CMT. We leave the exact construction details for future work. 244 | 245 | % For the Kate Commitment based approach, let us assume that each data chunk is prepended with an application identifier (ID) which is unique to the application. 246 | % % For our example, let the ID for \textit{R} be $R$. 247 | % Let the data matrix $D_{n \times m}$ be filled up column-wise and let the ordering be such that all transactions relevant to a particular application are put in contiguous chunks of data. Incomplete data chunks are padded appropriately. Let the application data be spread from $D[i_1][j_1]$ to $D[i_2][j_2]$, where $1 \leq i_1, i_2 \leq n$ and $1 \leq j_1 \leq j_2 \leq m$. 248 | 249 | % With this setup, an application client can query its data from a full node. The full node need to give openings to all chunks from $D[i_1][j_1]$ to $D[i_2][j_2]$, taken column-wise. On top of that, it also needs to give openings to $D[i_1-1][j_1]$ (or $D[n][j_1-1]$ if $i_1=0$) and $D[i_2+1][j_2]$ (or $D[0][j_2+1]$ if $i_2=n$). The client can then verify that for all openings within $D[i_1][j_1]$ to $D[i_2][j_2]$, the data starts with the correct ID and for the remaining two openings, the data has a different ID. This would prove the client that it has received all relevant data, under the assumption that the ordering is done correctly (equivalently, that supermajority of validators are honest in \DA). 250 | 251 | % In case the client approaches column full nodes, it would need to approach at most ($\lceil size/n \rceil + 2$) column full nodes. 252 | 253 | 254 | % \section{Related Work} 255 | % Lazyledger \cite{lazyledger} proposes a \DA{} construction using higher dimensional erasure coding. TODO: compare and contrast. 256 | 257 | % \section{Open Issues} 258 | % We note that a successful implementation of a \DA{} will need to address these issues: 259 | % \begin{itemize} 260 | % \item In Kate Commitment based scheme, a trusted setup phase is needed. A deeper look into the details of it is needed. Some representative numbers are present in \cite{dankrad_poly:2019}. 261 | % \item Aligning data chunks into field elements needs some engineering. Also, choosing a formally verified bilinear pairing library with high performance is critical. A good place to start would be blst library. 262 | % \item Choice of parameters need to be carefully addressed. In CMT approach, the number of hashes in the root, coding rate, hashes per chunk, base layer data per chunk, etc., need to be chosen. In Kate commitment approach, the number of columns, choice of underlying group, etc., need to be fixed. In both approaches, simple parallelisation is possible which would increase efficiency. 263 | % \end{itemize} 264 | 265 | \bibliographystyle{ACM-Reference-Format} 266 | \bibliography{DA_references} 267 | 268 | \end{document} 269 | -------------------------------------------------------------------------------- /reference document/README.md: -------------------------------------------------------------------------------- 1 | # Avail Reference Paper 2 | 3 | This introductory paper to Avail was originally published in Dec 2020. The paper has subsequently been updated to reflect the growth and development of the Avail project. 4 | 5 | The paper provides a comprehensive overview of the Avail Network and the way it solves problems facing blockchain scalability, interoperability and security. The paper will be updated as the Avail network matures. 6 | 7 | *Here you will find links to the current reference document for Avail along with a version history of previously published version.* 8 | 9 | ##### Current Paper 10 | - [V2.1](https://github.com/availproject/data-availability/blob/93c547ce4efce3e992b573179a8d22b3657fdcee/reference%20document/Avail%20Reference%20Paper%20v2.1%206%20Nov%202024.pdf) *Nov 6, 2024* 11 | ##### Version History 12 | - [V2](https://github.com/availproject/data-availability/blob/master/reference%20document/Avail%20Reference%20Paper%20v2%2017%20Sept%202024.pdf) Sep 17, 2024 13 | - [V1](https://github.com/availproject/data-availability/blob/master/reference%20document/Data%20Availability%20-%20Reference%20Document.pdf) Dec 2023 14 | --------------------------------------------------------------------------------