├── .gitignore ├── Makefile ├── test.html ├── README.md ├── pipe.c └── LICENSE /.gitignore: -------------------------------------------------------------------------------- 1 | *.swp 2 | *.swo 3 | objs/ 4 | objs/* 5 | webpipe 6 | -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | CC=gcc 2 | OBJDIR=objs 3 | SRCDIR=. 4 | 5 | SRCS=$(wildcard $(SRCDIR)/*.c) 6 | OBJS=$(patsubst $(SRCDIR)/%.c, $(OBJDIR)/%.o, $(SRCS)) 7 | 8 | CFLAGS+=$(ENV_CFLAGS) 9 | LDFLAGS+=$(ENV_LDFLAGS) 10 | CFLAGS+=-I/usr/include -Wall -O2 11 | ifndef STATIC_LIBWEBSOCKETS 12 | LDFLAGS+=-lwebsockets 13 | endif 14 | LDFLAGS+=-lpthread 15 | 16 | TARGET=webpipe 17 | 18 | .PHONY: all clean install 19 | 20 | all: $(TARGET) 21 | 22 | $(TARGET): $(OBJS) 23 | $(CC) $(CFLAGS) $^ -o $@ $(LDFLAGS) 24 | 25 | $(OBJS): | $(OBJDIR) 26 | $(OBJDIR): 27 | mkdir -p $@ 28 | 29 | $(OBJDIR)/%.o: $(SRCDIR)/%.c Makefile 30 | $(CC) $(CFLAGS) $< -c -o $@ 31 | 32 | clean: 33 | rm -rf $(OBJDIR) $(TARGET) 34 | 35 | install: $(TARGET) 36 | cp $(TARGET) /usr/local/bin/$(TARGET) 37 | -------------------------------------------------------------------------------- /test.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | 14 | 15 |
 

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27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # webpipe 2 | A simple command line websocket utility for piping messages to and from a browser 3 | 4 | ### Server 5 | 6 | while true; do date; sleep 1; done | webpipe -f test.html 7 | 8 | ### Client 9 | 10 | webpipe -i '{"type":"subscribe","product_id":"BTC-USD"}' wss://ws-feed.exchange.coinbase.com|sed -n 's/.*price":"\([0-9\.]*\)".*/\1/p' 11 | 12 | 13 | ## Installation 14 | 15 | 16 | git clone https://github.com/emgram769/webpipe && cd webpipe 17 | ./build.sh --install 18 | 19 | Or you can install the latest version of `libwebsockets` [(source here)](https://github.com/warmcat/libwebsockets) 20 | and run `make` instead of `./build.sh`. 21 | 22 | 23 | ## Try it out 24 | 25 | ./build.sh 26 | ./webpipe -f test.html 27 | 28 | Navigate to `localhost:8000` and open your browser's console. 29 | Type what ever you'd like into your terminal. 30 | 31 | ## Use it as a simple chat 32 | 33 | In one shell: 34 | 35 | webpipe 36 | and in another: 37 | 38 | webpipe localhost:8000 39 | 40 | ## Usage 41 | 42 | ####Client: 43 | 44 | webpipe somesite.com 45 | 46 | for example 47 | 48 | webpipe -i '{"type":"subscribe","product_id":"BTC-USD"}' wss://ws-feed.exchange.coinbase.com 49 | 50 | 51 | ####Server: 52 | 53 | webpipe -p 5000 -f file.html 54 | 55 | #### Flags 56 | - `-p [port]` to specify a port number to serve on. 57 | - `-f [file]` to host an HTML file (hardcoded mime-type). 58 | - `-i [message]` to send a message once the server is connected. This is useful for subscription based services. 59 | - `-s` to attempt to connect with SSL. 60 | - `-D [delimiter]` to specify a character other than `\n` as a delimiter. 61 | - `-d` to see debug messages in stderr. 62 | - `-U [max users]` to specify the maximum number of connections. 63 | - `-B [max buffer size]` to specify the maximum size of any sent message. 64 | -------------------------------------------------------------------------------- /pipe.c: -------------------------------------------------------------------------------- 1 | #include 2 | #include 3 | #include 4 | #include 5 | #include 6 | 7 | #define DEFAULT_MAX_USERS 1024 8 | #define DEFAULT_MAX_BUFFER 1024 9 | #define DEFAULT_PORT 8000 10 | #define DEFAULT_DELIMITER '\n' 11 | 12 | static struct lws_protocols *protocols; 13 | static struct lws_context *context; 14 | static uint16_t port = DEFAULT_PORT; 15 | static uint32_t max_users = DEFAULT_MAX_USERS; 16 | static uint32_t max_buffer_size = DEFAULT_MAX_BUFFER; 17 | static uint32_t use_ssl = 0; 18 | 19 | static char *served_html_file; 20 | static char *first_message; 21 | static char delimiter = DEFAULT_DELIMITER; 22 | 23 | static pthread_mutex_t users_mutex = PTHREAD_MUTEX_INITIALIZER; 24 | static struct lws **users; 25 | static uint32_t num_users; 26 | 27 | static void send_buffer(char *buffer, uint32_t len); 28 | 29 | static int ws_server_callback(struct lws *wsi, 30 | enum lws_callback_reasons reason, 31 | void *user, 32 | void *in, 33 | size_t len) { 34 | switch (reason) { 35 | case LWS_CALLBACK_HTTP: 36 | { 37 | if (served_html_file) { 38 | lws_serve_http_file(wsi, served_html_file, "text/html", NULL, 0); 39 | fprintf(stderr, "HTTP Request: serving %s\n", served_html_file); 40 | } else { 41 | fprintf(stderr, "HTTP Request error: no file to serve (use the -f flag)\n"); 42 | } 43 | break; 44 | } 45 | case LWS_CALLBACK_RECEIVE: 46 | { 47 | printf("%s\n", (char *)in); 48 | fflush(NULL); 49 | break; 50 | } 51 | case LWS_CALLBACK_ESTABLISHED: 52 | { 53 | pthread_mutex_lock(&users_mutex); 54 | users[num_users++] = wsi; 55 | pthread_mutex_unlock(&users_mutex); 56 | fprintf(stderr, "Connect: %d users\n", num_users); 57 | break; 58 | } 59 | case LWS_CALLBACK_CLOSED: 60 | { 61 | pthread_mutex_lock(&users_mutex); 62 | // Find the user and remove them 63 | int i; 64 | for (i = 0; i < num_users; i++) { 65 | if (wsi == users[i]) { 66 | // If there are users beyond this, move them closer 67 | if (i + 1 < num_users) { 68 | memmove(&users[i], &users[i+1], (num_users - i - 1) * sizeof(struct lws *)); 69 | } 70 | num_users--; 71 | } 72 | } 73 | pthread_mutex_unlock(&users_mutex); 74 | fprintf(stderr, "Disconnect: %d users\n", num_users); 75 | break; 76 | } 77 | default: break; 78 | } 79 | return 0; 80 | } 81 | 82 | static int ws_client_callback(struct lws *wsi, 83 | enum lws_callback_reasons reason, 84 | void *user, 85 | void *in, 86 | size_t len) { 87 | switch (reason) { 88 | case LWS_CALLBACK_CLIENT_CONNECTION_ERROR: 89 | fprintf(stderr, "Error attempting to connect: %s\n", (char *)in); 90 | exit(0); 91 | break; 92 | case LWS_CALLBACK_CLIENT_ESTABLISHED: 93 | fprintf(stderr, "Successfully connected to server.\n"); 94 | if (first_message) { 95 | send_buffer(first_message, strlen(first_message)); 96 | } 97 | break; 98 | case LWS_CALLBACK_CLOSED: 99 | fprintf(stderr, "Connection closed.\n"); 100 | exit(0); 101 | break; 102 | case LWS_CALLBACK_CLIENT_RECEIVE: 103 | printf("%s\n", (char *)in); 104 | fflush(NULL); 105 | break; 106 | default: 107 | break; 108 | } 109 | return 0; 110 | } 111 | 112 | static int initialize_ws_server(void) { 113 | struct lws_protocols _protocols[] = { 114 | { 115 | "default", 116 | ws_server_callback, 117 | 0, 118 | max_buffer_size 119 | }, 120 | { NULL, NULL, 0 } 121 | }; 122 | protocols = malloc(sizeof(_protocols)); 123 | memcpy(protocols, _protocols, sizeof(_protocols)); 124 | 125 | struct lws_context_creation_info *info = calloc(1, sizeof(struct lws_context_creation_info)); 126 | info->port = port; 127 | info->iface = NULL; 128 | info->protocols = protocols; 129 | info->extensions = NULL; 130 | context = lws_create_context(info); 131 | if (context == NULL) { 132 | fprintf(stderr, "Unable to create lws context.\n"); 133 | goto error; 134 | } 135 | 136 | return 0; 137 | 138 | error: 139 | free(protocols); 140 | free(info); 141 | return -1; 142 | } 143 | 144 | static int initialize_ws_client(char *address) { 145 | struct lws_protocols _protocols[] = { 146 | { 147 | "default", 148 | ws_client_callback, 149 | 0, 150 | max_buffer_size 151 | }, 152 | { NULL, NULL, 0 } 153 | }; 154 | 155 | protocols = malloc(sizeof(_protocols)); 156 | memcpy(protocols, _protocols, sizeof(_protocols)); 157 | 158 | struct lws_context_creation_info *info = calloc(1, sizeof(struct lws_context_creation_info)); 159 | info->port = CONTEXT_PORT_NO_LISTEN; 160 | info->iface = NULL; 161 | info->protocols = protocols; 162 | info->extensions = NULL; 163 | 164 | context = lws_create_context(info); 165 | if (context == NULL) { 166 | fprintf(stderr, "Unable to create lws context.\n"); 167 | goto error; 168 | } 169 | 170 | // Parse out the address:port/path 171 | char hostname[100]; 172 | char path[100]; 173 | // Defaults 174 | port = 80; 175 | strcpy(path, "/"); 176 | 177 | // Check for ws:// or wss:// 178 | const char wss_prefix[] = "wss://"; 179 | const char ws_prefix[] = "ws://"; 180 | 181 | size_t wss_prefix_len = strlen(wss_prefix); 182 | size_t ws_prefix_len = strlen(ws_prefix); 183 | 184 | if (strncmp(wss_prefix, address, wss_prefix_len) == 0) { 185 | address = &(address[wss_prefix_len]); 186 | port = 443; 187 | use_ssl = 1; 188 | } else if (strncmp(ws_prefix, address, ws_prefix_len) == 0) { 189 | address = &(address[ws_prefix_len]); 190 | } 191 | 192 | if (sscanf(address, "%99[^:]:%99hu/%99[^\n]", hostname, &port, &path[1]) < 2) { 193 | sscanf(address, "%99[^/]/%99[^\n]", hostname, &path[1]); 194 | } 195 | 196 | char address_w_port[1024]; 197 | sprintf(address_w_port, "%s:%d", hostname, port); 198 | 199 | if (port != 80) { 200 | fprintf(stderr, "Connecting to %s on %s\n", address_w_port, path); 201 | } else { 202 | fprintf(stderr, "Connecting to %s on %s\n", hostname, path); 203 | } 204 | 205 | struct lws *client_wsi = lws_client_connect(context, hostname, port, use_ssl, path, address_w_port, NULL, NULL, -1); 206 | if (client_wsi == NULL) { 207 | fprintf(stderr, "Unable to connect to client.\n"); 208 | goto error; 209 | } 210 | users = calloc(1, sizeof(struct lws *)); 211 | users[0] = client_wsi; 212 | num_users = 1; 213 | 214 | return 0; 215 | 216 | error: 217 | free(protocols); 218 | free(info); 219 | return -1; 220 | } 221 | 222 | static void *ws_thread_loop(void *args) { 223 | while(1) { 224 | lws_service(context, 50); 225 | } 226 | return NULL; 227 | } 228 | 229 | static void send_buffer(char *buffer, uint32_t len) { 230 | fprintf(stderr, "Sending %s to %d users\n", buffer, num_users); 231 | char out_buffer[LWS_SEND_BUFFER_PRE_PADDING + len + LWS_SEND_BUFFER_POST_PADDING]; 232 | memset(&out_buffer[LWS_SEND_BUFFER_PRE_PADDING], 0, len); 233 | strncpy(&out_buffer[LWS_SEND_BUFFER_PRE_PADDING], buffer, len); 234 | int i; 235 | pthread_mutex_lock(&users_mutex); 236 | for (i = 0; i < num_users; i++) { 237 | lws_write(users[i], (unsigned char *)&out_buffer[LWS_SEND_BUFFER_PRE_PADDING], len, LWS_WRITE_TEXT); 238 | } 239 | pthread_mutex_unlock(&users_mutex); 240 | } 241 | 242 | static void turn_off_errors(void) { 243 | // Remove errors 244 | int devnull_fd = open("/dev/null", O_WRONLY); 245 | dup2(devnull_fd, STDERR_FILENO); 246 | } 247 | 248 | static void read_input(void) { 249 | char buffer[max_buffer_size]; 250 | uint32_t pos = 0; 251 | char ch; 252 | while (read(STDIN_FILENO, &ch,1) > 0) { 253 | if (ch == delimiter) { 254 | buffer[pos] = '\0'; 255 | send_buffer(buffer, pos); 256 | pos = 0; 257 | continue; 258 | } else { 259 | buffer[pos++] = ch; 260 | } 261 | if (pos >= max_buffer_size) { 262 | fprintf(stderr, "Max buffer size exceeded!"); 263 | send_buffer(buffer, pos); 264 | pos = 0; 265 | } 266 | } 267 | } 268 | 269 | static void print_usage() { 270 | printf("webpipe [-p port] [-f file.html] [-d] [server]\n"); 271 | } 272 | 273 | int main(int argc, char *argv[]) { 274 | int debug_flag = 0; 275 | int c; 276 | while((c = getopt(argc, argv, "p:U:B:f:i:D:sdh?")) != -1) { 277 | switch (c) { 278 | case 'p': 279 | port = atoi(optarg); 280 | break; 281 | case 'U': 282 | max_users = atoi(optarg); 283 | break; 284 | case 'B': 285 | max_buffer_size = atoi(optarg); 286 | break; 287 | case 'f': 288 | served_html_file = optarg; 289 | break; 290 | case 'i': 291 | first_message = optarg; 292 | break; 293 | case 'D': 294 | delimiter = optarg[0]; 295 | break; 296 | case 'd': 297 | debug_flag = 1; 298 | break; 299 | case 's': 300 | use_ssl = 2; 301 | break; 302 | case 'h': 303 | case '?': 304 | default: 305 | print_usage(); 306 | break; 307 | } 308 | } 309 | 310 | if (!debug_flag) { 311 | turn_off_errors(); 312 | } 313 | 314 | int err = 0; 315 | 316 | if (argv[optind] != NULL) { 317 | fprintf(stderr, "Starting a client connection to %s.\n", argv[optind]); 318 | // Start a client 319 | err = initialize_ws_client(argv[optind]); 320 | } else { 321 | fprintf(stderr, "Starting a server.\n"); 322 | users = calloc(max_users, sizeof(struct lws *)); 323 | // Start a server 324 | err = initialize_ws_server(); 325 | } 326 | sleep(1); 327 | // Start websocket connection on a different thread. 328 | pthread_t ws_thread; 329 | if (!err) { 330 | pthread_create(&ws_thread, NULL, ws_thread_loop, NULL); 331 | } 332 | 333 | // Read input. 334 | read_input(); 335 | 336 | return 0; 337 | } 338 | 339 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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Patents. 472 | 473 | A "contributor" is a copyright holder who authorizes use under this 474 | License of the Program or a work on which the Program is based. The 475 | work thus licensed is called the contributor's "contributor version". 476 | 477 | A contributor's "essential patent claims" are all patent claims 478 | owned or controlled by the contributor, whether already acquired or 479 | hereafter acquired, that would be infringed by some manner, permitted 480 | by this License, of making, using, or selling its contributor version, 481 | but do not include claims that would be infringed only as a 482 | consequence of further modification of the contributor version. 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You may not convey a covered 525 | work if you are a party to an arrangement with a third party that is 526 | in the business of distributing software, under which you make payment 527 | to the third party based on the extent of your activity of conveying 528 | the work, and under which the third party grants, to any of the 529 | parties who would receive the covered work from you, a discriminatory 530 | patent license (a) in connection with copies of the covered work 531 | conveyed by you (or copies made from those copies), or (b) primarily 532 | for and in connection with specific products or compilations that 533 | contain the covered work, unless you entered into that arrangement, 534 | or that patent license was granted, prior to 28 March 2007. 535 | 536 | Nothing in this License shall be construed as excluding or limiting 537 | any implied license or other defenses to infringement that may 538 | otherwise be available to you under applicable patent law. 539 | 540 | 12. No Surrender of Others' Freedom. 541 | 542 | If conditions are imposed on you (whether by court order, agreement or 543 | otherwise) that contradict the conditions of this License, they do not 544 | excuse you from the conditions of this License. If you cannot convey a 545 | covered work so as to satisfy simultaneously your obligations under this 546 | License and any other pertinent obligations, then as a consequence you may 547 | not convey it at all. For example, if you agree to terms that obligate you 548 | to collect a royalty for further conveying from those to whom you convey 549 | the Program, the only way you could satisfy both those terms and this 550 | License would be to refrain entirely from conveying the Program. 551 | 552 | 13. Use with the GNU Affero General Public License. 553 | 554 | Notwithstanding any other provision of this License, you have 555 | permission to link or combine any covered work with a work licensed 556 | under version 3 of the GNU Affero General Public License into a single 557 | combined work, and to convey the resulting work. The terms of this 558 | License will continue to apply to the part which is the covered work, 559 | but the special requirements of the GNU Affero General Public License, 560 | section 13, concerning interaction through a network will apply to the 561 | combination as such. 562 | 563 | 14. Revised Versions of this License. 564 | 565 | The Free Software Foundation may publish revised and/or new versions of 566 | the GNU General Public License from time to time. Such new versions will 567 | be similar in spirit to the present version, but may differ in detail to 568 | address new problems or concerns. 569 | 570 | Each version is given a distinguishing version number. If the 571 | Program specifies that a certain numbered version of the GNU General 572 | Public License "or any later version" applies to it, you have the 573 | option of following the terms and conditions either of that numbered 574 | version or of any later version published by the Free Software 575 | Foundation. If the Program does not specify a version number of the 576 | GNU General Public License, you may choose any version ever published 577 | by the Free Software Foundation. 578 | 579 | If the Program specifies that a proxy can decide which future 580 | versions of the GNU General Public License can be used, that proxy's 581 | public statement of acceptance of a version permanently authorizes you 582 | to choose that version for the Program. 583 | 584 | Later license versions may give you additional or different 585 | permissions. However, no additional obligations are imposed on any 586 | author or copyright holder as a result of your choosing to follow a 587 | later version. 588 | 589 | 15. Disclaimer of Warranty. 590 | 591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT 593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY 594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, 595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM 597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF 598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 599 | 600 | 16. Limitation of Liability. 601 | 602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS 604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY 605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE 606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF 607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD 608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), 609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF 610 | SUCH DAMAGES. 611 | 612 | 17. Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | {one line to give the program's name and a brief idea of what it does.} 635 | Copyright (C) {year} {name of author} 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | {project} Copyright (C) {year} {fullname} 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | --------------------------------------------------------------------------------