├── .gitignore ├── examples └── colordemo-example.png ├── pdm.lock ├── colordemo ├── colors.py ├── __init__.py ├── __main__.py ├── color_display.py └── terminal_query.py ├── pyproject.toml ├── CHANGELOG.md ├── README.md └── COPYING /.gitignore: -------------------------------------------------------------------------------- 1 | *~ 2 | *.swp 3 | *.pyc 4 | build/ 5 | dist/ 6 | *.egg-info 7 | 8 | .pdm-python 9 | .pdm.toml 10 | -------------------------------------------------------------------------------- /examples/colordemo-example.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/dranjan/python-colordemo/HEAD/examples/colordemo-example.png -------------------------------------------------------------------------------- /pdm.lock: -------------------------------------------------------------------------------- 1 | # This file is @generated by PDM. 2 | # It is not intended for manual editing. 3 | 4 | [metadata] 5 | lock_version = "4.2" 6 | cross_platform = true 7 | groups = ["default"] 8 | content_hash = "sha256:b151d65006a47670ce0477b322dbd276233a188e1dc4c9af00e09a575e9309c5" 9 | 10 | [metadata.files] 11 | -------------------------------------------------------------------------------- /colordemo/colors.py: -------------------------------------------------------------------------------- 1 | # Copyright 2012 Darsh Ranjan 2 | # 3 | # This file is part of termcolors. 4 | # 5 | # termcolors is free software: you can redistribute it and/or modify 6 | # it under the terms of the GNU General Public License as published by 7 | # the Free Software Foundation, either version 3 of the License, or 8 | # (at your option) any later version. 9 | # 10 | # termcolors is distributed in the hope that it will be useful, but 11 | # WITHOUT ANY WARRANTY; without even the implied warranty of 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 | # General Public License for more details. 14 | # 15 | # You should have received a copy of the GNU General Public License 16 | # along with termcolors. If not, see 17 | # . 18 | 19 | from collections import namedtuple 20 | 21 | RGBAColor = namedtuple('RGBAColor', ('r', 'g', 'b', 'a')) 22 | -------------------------------------------------------------------------------- /pyproject.toml: -------------------------------------------------------------------------------- 1 | [project] 2 | name = "colordemo" 3 | version = "0.3.0" 4 | description = "RGB queries on xterm-like terminals" 5 | authors = [ 6 | {name = "Darsh Ranjan", email = "dranjan@berkeley.edu"}, 7 | ] 8 | readme = "README.md" 9 | license = {file = "COPYING"} 10 | requires-python = ">=3.0" 11 | dependencies = [] 12 | classifiers = [ 13 | "Development Status :: 4 - Beta", 14 | "License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)", 15 | "Operating System :: OS Independent", 16 | "Programming Language :: Python :: 3", 17 | ] 18 | 19 | [project.scripts] 20 | colordemo = "colordemo.__main__:main" 21 | 22 | [build-system] 23 | requires = ["pdm-backend"] 24 | build-backend = "pdm.backend" 25 | 26 | [project.urls] 27 | Homepage = "https://github.com/dranjan/python-colordemo" 28 | Documentation = "https://github.com/dranjan/python-colordemo" 29 | Repository = "https://github.com/dranjan/python-colordemo" 30 | -------------------------------------------------------------------------------- /colordemo/__init__.py: -------------------------------------------------------------------------------- 1 | # Copyright 2012-2023 Darsh Ranjan 2 | # 3 | # This file is part of termcolors. 4 | # 5 | # termcolors is free software: you can redistribute it and/or modify 6 | # it under the terms of the GNU General Public License as published by 7 | # the Free Software Foundation, either version 3 of the License, or 8 | # (at your option) any later version. 9 | # 10 | # termcolors is distributed in the hope that it will be useful, but 11 | # WITHOUT ANY WARRANTY; without even the implied warranty of 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 | # General Public License for more details. 14 | # 15 | # You should have received a copy of the GNU General Public License 16 | # along with termcolors. If not, see 17 | # . 18 | 19 | from .terminal_query import (TerminalQueryContext, 20 | TerminalQueryError, 21 | TerminalSetupError, 22 | NoResponseError, 23 | TerminalUninitializedError) 24 | 25 | from .colors import RGBAColor 26 | -------------------------------------------------------------------------------- /CHANGELOG.md: -------------------------------------------------------------------------------- 1 | # Change log 2 | 3 | All notable changes to this project will be documented here. 4 | 5 | ## [Unreleased] 6 | ### Fixed 7 | - Support status of `st` in the documentation. 8 | 9 | ## [0.3.0] - 2023-07-29 10 | ### Added 11 | - Support for newer urxvt versions. 12 | - Change log. 13 | 14 | ### Removed 15 | - Support for older urxvt versions, which are now considered buggy. 16 | 17 | ## [0.2.1] - 2023-07-24 18 | ### Added 19 | - Improved documentation. 20 | 21 | ### Removed 22 | - Code path specific to Python 2. 23 | 24 | ## [0.2] - 2023-07-22 25 | ### Added 26 | - Improved documentation. 27 | 28 | ### Fixed 29 | - Changed line endings to be compliant with specification. 30 | - Improved validation of property and element names. 31 | 32 | ## 0.1 - 2023-07-22 33 | ### Added 34 | - Initial implementation. 35 | 36 | (This code was largely written in 2012, with minor updates since then.) 37 | 38 | [Unreleased]: https://github.com/dranjan/python-colordemo/compare/v0.3.0...HEAD 39 | [0.3.0]: https://github.com/dranjan/python-colordemo/compare/v0.2.1...v0.3.0 40 | [0.2.1]: https://github.com/dranjan/python-colordemo/compare/v0.2...v0.2.1 41 | [0.2]: https://github.com/dranjan/python-colordemo/compare/v0.1...v0.2 42 | -------------------------------------------------------------------------------- /colordemo/__main__.py: -------------------------------------------------------------------------------- 1 | # Copyright 2012-2023 Darsh Ranjan 2 | # 3 | # This file is part of termcolors. 4 | # 5 | # termcolors is free software: you can redistribute it and/or modify 6 | # it under the terms of the GNU General Public License as published by 7 | # the Free Software Foundation, either version 3 of the License, or 8 | # (at your option) any later version. 9 | # 10 | # termcolors is distributed in the hope that it will be useful, but 11 | # WITHOUT ANY WARRANTY; without even the implied warranty of 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 | # General Public License for more details. 14 | # 15 | # You should have received a copy of the GNU General Public License 16 | # along with termcolors. If not, see 17 | # . 18 | 19 | from sys import (stdout, stderr) 20 | from argparse import (ArgumentParser, ArgumentError) 21 | 22 | from .color_display import ColorDisplay 23 | 24 | ######################################################################## 25 | # Command-line arguments 26 | 27 | timeout_dft = -1 28 | 29 | parser = ArgumentParser( 30 | description="Python script to show off terminal colors.", 31 | epilog="Run this script from the terminal whose colors " + 32 | "you want to showcase. " + 33 | "Only xterm-like terminals are supported " + 34 | "(see the README).") 35 | 36 | mode_group = parser.add_mutually_exclusive_group() 37 | 38 | p_choices = [16, 88, 256] 39 | 40 | arg_p = mode_group.add_argument( 41 | '-p', '--pretty', 42 | action='store_true', default=False, 43 | help="show colors 0 through N-1 in a pretty format. " + 44 | ("N must belong to %r. " % p_choices) + 45 | "If N > 16, it should be the actual number of colors " + 46 | "supported by the terminal, or the output will almost " + 47 | "certainly not be pretty.") 48 | 49 | mode_group.add_argument( 50 | '-f', '--flat', 51 | action='store_true', default=False, 52 | help="show a simple table with colors 0 through N-1. ") 53 | 54 | parser.add_argument( 55 | 'n', nargs='?', metavar='N', 56 | type=int, default=16, 57 | help="number of colors to show. " + 58 | "Unless you explicitly supply -p/--pretty or -f/--flat, " + 59 | "--pretty is used if possible and --flat is used " + 60 | "otherwise. " + 61 | "N defaults to 16, showing the ANSI colors 0-15. " + 62 | "If N is 0, the script will attempt to determine the " + 63 | "maximum number of colors automatically " + 64 | "(which may be slow).") 65 | 66 | parser.add_argument( 67 | '--no-fgbg', 68 | action='store_false', dest='fgbg', default=True, 69 | help="suppress display of foreground/background colors.") 70 | 71 | parser.add_argument( 72 | '--no-query', 73 | action='store_false', dest='do_query', default=True, 74 | help="don't try to query any RGB values from the terminal " + 75 | "and just use placeholders.") 76 | 77 | parser.add_argument( 78 | '-t', '--timeout', metavar='T', 79 | type=int, default=timeout_dft, 80 | help="how long to wait for the terminal to " 81 | "respond to a query, in milliseconds " + 82 | "[default: {0}]. ".format(timeout_dft) + 83 | "If your output has '?' characters " + 84 | "instead of RGB values " + 85 | "or junk printed after the script runs, " + 86 | "increasing this value may or may not " + 87 | "help, depending on the terminal. " + 88 | "A negative T will behave like infinity.") 89 | 90 | parser.add_argument( 91 | '-l', '--level', metavar='L', 92 | type=int, default=3, 93 | help="choose how much color to use in the output. " + 94 | "(0 = no color; 3 = most color [default])") 95 | 96 | parser.add_argument( 97 | '--screen-forward', '--tmux-forward', 98 | action='store_true', default=False, 99 | help="attempt to pass terminal queries through a tmux " + 100 | "session (ignored if this is not a tmux session)") 101 | 102 | ######################################################################## 103 | 104 | 105 | def main(): 106 | args = parser.parse_args() 107 | 108 | assert not (args.pretty and args.flat) 109 | 110 | if args.pretty: 111 | if args.n not in p_choices: 112 | raise ArgumentError( 113 | arg_p, 114 | "N must belong to %r" % p_choices) 115 | 116 | with ColorDisplay(0, args.timeout, args.level, args.do_query, 117 | args.screen_forward) as C: 118 | 119 | if args.n == 0: 120 | args.n = C.get_num_colors(args.timeout) 121 | 122 | if not (args.pretty or args.flat): 123 | if args.n in p_choices: 124 | args.pretty = True 125 | else: 126 | args.flat = True 127 | 128 | if args.level >= 1: 129 | stdout.write(C.reset) 130 | 131 | if args.fgbg: 132 | C.show_fgbg() 133 | 134 | if args.pretty: 135 | assert args.n in p_choices 136 | 137 | stdout.write('\n ANSI colors:\n\n') 138 | C.show_ansi() 139 | 140 | if args.n > 16: 141 | stdout.write('\n RGB cube:\n\n') 142 | C.show_color_cube(args.n) 143 | 144 | stdout.write(' Grayscale ramp:\n\n') 145 | C.show_grayscale_ramp(args.n) 146 | else: 147 | C.show_colors(args.n) 148 | 149 | if C.num_errors > 0: 150 | stderr.write("Warning: not all queries succeeded\n" + 151 | "Warning: (output contains " + 152 | "placeholders and may be inaccurate)\n") 153 | 154 | 155 | if __name__ == "__main__": 156 | main() 157 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # `colordemo` 2 | 3 | `colordemo` is a Python package implementing RGB queries on xterm-like 4 | terminals. It includes a demo script for presenting terminal color 5 | schemes, complete with RGB hex codes. 6 | 7 |
8 | 9 |
10 | 11 | ## Quick start 12 | 13 | There are many ways to run the demo script, and we will briefly describe 14 | them here. Note that with any of the methods below, the `colordemo` 15 | tool can accept command-line options. To see which options are available, 16 | use `--help` with any of the methods, e.g., 17 | 18 | pipx run colordemo --help 19 | 20 | ### Using `pipx` 21 | 22 | With only an active internet connection and the `pipx` Python utility, 23 | the script can be run directly without installation: 24 | 25 | pipx run colordemo 26 | 27 | Alternatively, it can also be installed explicitly and run that way: 28 | 29 | pipx install colordemo 30 | colordemo 31 | 32 | ### Using `pip` 33 | 34 | The package can also be installed and run as a normal Python package 35 | using `pip` (preferably in a `virtualenv` environment): 36 | 37 | pip install colordemo 38 | colordemo 39 | 40 | # Equivalent 41 | python -m colordemo 42 | 43 | ### From the source tree 44 | 45 | Finally, the script can be run easily from the source tree directly. 46 | This package has no dependencies besides Python, so no actions are 47 | needed besides cloning the repository. 48 | 49 | git clone 'git@github.com:dranjan/python-colordemo.git' 50 | cd python-colordemo 51 | python -m colordemo 52 | 53 | ## Overview of functionality 54 | 55 | `colordemo` allows you to programmatically determine the RGB values of 56 | some terminals' ANSI colors (or more colors, if the terminal has them). 57 | The functions must be run from the terminal whose colors you want to 58 | determine, and with caveats if within a screen or tmux session (see 59 | below for more on this). Not all terminal types are supported (see the 60 | next section). 61 | 62 | ## Terminal support 63 | 64 | The fundamental requirement for a terminal to be supported by `colordemo` 65 | is for it to support the xterm-like OSC ("Operating System Command") control 66 | sequences, listed under "Operating System Commands" here: 67 | 68 | https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h3-Operating-System-Commands 69 | 70 | (Sometimes this support can be ascertained from the documentation of 71 | the terminal, but often you just need to try it.) 72 | 73 | We call these terminals "xterm-like". If a terminal emulator doesn't 74 | support those sequences, then it won't be supported here. 75 | There may be other ways to obtain RGB values for these terminals, such 76 | as parsing configuration files or perhaps parsing the output of 77 | `xrdb --query`, but we have no plans to implement any of these. 78 | The only way to add support for a currently unsupported terminal is to 79 | patch the terminal with support for the OSC sequences. 80 | 81 | There are too many terminals for us to test all of them, so the lists 82 | below are not exhaustive. If a terminal isn't mentioned in one of the 83 | following subsections, attempt at your own risk! 84 | 85 | ### Fully supported terminals 86 | 87 | **Note:** a terminal being "supported" doesn't mean `colordemo` will 88 | work well on all versions of the terminal. For many terminals, proper 89 | support for the xterm-like OSC sequences was added and improved over 90 | time. 91 | 92 | - xterm 93 | - urxvt 94 | - VTE-based terminals, including: 95 | - vte 96 | - Terminal (XFCE) 97 | - gnome-terminal 98 | - terminator 99 | - tilda 100 | - (etc.) 101 | - st 102 | - kitty 103 | - alacritty 104 | - wezterm 105 | - ttyd 106 | - Ghostty 107 | - (etc.) 108 | 109 | ### Unsupported terminals 110 | 111 | - Konsole-based terminals, which are buggy: 112 | - Konsole 113 | - yakuake 114 | - (etc.) 115 | - terminology 116 | - anything in Emacs (Eshell, vterm, ...) 117 | - Linux basic TTY (text mode without X) 118 | - (etc.) 119 | 120 | Some terminals (like terminology) don't seem to allow their colors to be 121 | queried dynamically, so all RGB queries will fail, but the failure can 122 | be detected. The demo script will therefore be able to output a color 123 | table, but without RGB values. 124 | 125 | Other terminals (like Konsole) seem to support the query codes but are 126 | extremely buggy, returning incorrect values and even segfaulting 127 | sometimes. 128 | 129 | In other cases (like older versions of the basic TTY), `colordemo` will garble 130 | the TTY and make it unreadable. (Try `tput reset` to restore it 131 | to something usable.) 132 | 133 | ## Note regarding screen and tmux 134 | 135 | It generally doesn't make sense to query a terminal from inside a screen 136 | or tmux session, since a single screen or tmux session can be attached 137 | to multiple terminals. However, in the special case of being attached 138 | to a single terminal, it is possible because tmux and screen provide 139 | (different) methods to pass control sequences through to the attached 140 | terminal. Of course, it makes no sense to try this if there are 141 | multiple terminals attached, and you should expect crazy results if you 142 | do. Thus, forwarding queries through screen or tmux is currently an 143 | opt-in feature (see the `screen_forward` optional argument in 144 | `TerminalQueryContext.__init__` or the 145 | `--screen-forward`/`--tmux-forward` command-line options). 146 | This will fail inside a nested screen or tmux session. 147 | 148 | (Not using the optional screen/tmux control-passthrough support, it's 149 | interesting to observe that screen and tmux emulate a 256-color terminal 150 | independently of the terminal(s) to which they are attached, which is 151 | very apparent if you run the script with 256-color output on a screen 152 | session attached to a terminal with 8- or 16-color terminfo (or with 153 | TERM set to such).) 154 | 155 | ## Python API 156 | 157 | For greater flexbility, the functionality of this package can also be 158 | accessed through its Python API. For example, this could be useful to 159 | create new color scheme demo scripts. 160 | 161 | The primary interface is the context manager, 162 | `colordemo.TerminalQueryContext`. The color queries must be performed 163 | inside the context manager's context. 164 | 165 | ```Python Console 166 | import colordemo 167 | 168 | with colordemo.TerminalQueryContext() as tq: 169 | # Simplest method: get everything at once. 170 | # This provides a list of RGBAColor instances. 171 | colors = tq.get_all_indexed_colors() 172 | 173 | # Alternatively, you can query individual colors. 174 | n = tq.get_num_colors() 175 | colors = [tq.get_indexed_color(k) for k in range(n)] 176 | 177 | # The foreground and background colors need to 178 | # be queried separately: 179 | fg = tq.get_fg() 180 | bg = tq.get_bg() 181 | 182 | # Color values are represented as instances of `RGBAColor`, which is 183 | # a specialization of `namedtuple`. 184 | (r, g, b, a) = fg 185 | 186 | # Equivalent: 187 | r, g, b, a = fg.r, fg.g, fg.b, fg.a 188 | 189 | # Color components are floating-point numbers in the range [0, 1]. 190 | # To convert these to two-digit hex codes: 191 | r_hex = '%02x' % (int(r * 0xffff) // 256) # etc. 192 | ``` 193 | 194 | ## Credits 195 | 196 | - dranjan: main implementation 197 | - oblique: improved tmux support 198 | - Xyne: much useful discussion and review 199 | -------------------------------------------------------------------------------- /colordemo/color_display.py: -------------------------------------------------------------------------------- 1 | # Copyright 2012-2023 Darsh Ranjan 2 | # 3 | # This file is part of termcolors. 4 | # 5 | # termcolors is free software: you can redistribute it and/or modify 6 | # it under the terms of the GNU General Public License as published by 7 | # the Free Software Foundation, either version 3 of the License, or 8 | # (at your option) any later version. 9 | # 10 | # termcolors is distributed in the hope that it will be useful, but 11 | # WITHOUT ANY WARRANTY; without even the implied warranty of 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 | # General Public License for more details. 14 | # 15 | # You should have received a copy of the GNU General Public License 16 | # along with termcolors. If not, see 17 | # . 18 | 19 | from collections import defaultdict 20 | from sys import stdout 21 | 22 | from .terminal_query import TerminalQueryContext 23 | 24 | 25 | class ColorDisplay(TerminalQueryContext): 26 | """ 27 | Class for producing a colored display of terminal RGB values. It's 28 | best to use this class as a context manager, which will properly set 29 | and reset the terminal's attributes. 30 | """ 31 | 32 | def __init__(self, tty_fd, 33 | timeout=100, color_level=3, do_query=True, 34 | screen_forward=False): 35 | """ 36 | Arguments: 37 | tty_fd: open file descriptor connected to a terminal. 38 | timeout: same interpretation as in rgb_query. A larger 39 | timeout will be used a small number of times to test the 40 | capabilities of the terminal. 41 | color_level: how much color should be in the output. Use 0 42 | to suppress all color and 3 or greater for maximum 43 | coloredness. 44 | do_query: whether to attempt to query RGB values from the 45 | terminal or just use placeholders everywhere. 46 | screen_forward: whether to attempt to forward queries 47 | through a screen or tmux session if we are in one. 48 | """ 49 | TerminalQueryContext.__init__(self, tty_fd, screen_forward) 50 | 51 | self.timeout = timeout 52 | self.color_level = color_level 53 | self.do_query = do_query 54 | 55 | def none_factory(): 56 | return None 57 | 58 | # colors for highlighting 59 | self.hi = defaultdict(none_factory) 60 | 61 | self.hi['['] = 10 62 | self.hi[']'] = 10 63 | self.hi['+'] = 9 64 | self.hi['/'] = 9 65 | 66 | for c in '0123456789ABCDEF': 67 | self.hi[c] = 12 68 | 69 | # String to use for color values that couldn't be determined 70 | self.rgb_placeholder = '??????' 71 | self.fmt = '{:02X}{:02X}{:02X}' 72 | self.scale = 0xff 73 | 74 | def __enter__(self): 75 | TerminalQueryContext.__enter__(self) 76 | 77 | # try getting the rgb value for color 0 to decide whether to 78 | # bother trying to query any more colors. 79 | self.do_query = (self.do_query and 80 | self.get_indexed_color(0, self.timeout*2)) 81 | 82 | if self.color_level >= 1: 83 | stdout.write(self.reset) 84 | 85 | return self 86 | 87 | def __exit__(self, exc_type, exc_value, traceback): 88 | if self.color_level >= 1: 89 | stdout.write(self.reset) 90 | 91 | TerminalQueryContext.__exit__(self, exc_type, exc_value, 92 | traceback) 93 | 94 | def show_fgbg(self): 95 | """ 96 | Show the foreground and background colors. 97 | 98 | Errors: 99 | TerminalUninitializedError: if this instance's context has 100 | not been entered. 101 | """ 102 | if self.do_query: 103 | bg = self.format(self.get_bg(timeout=self.timeout)) 104 | fg = self.format(self.get_fg(timeout=self.timeout)) 105 | else: 106 | bg = self.rgb_placeholder 107 | fg = self.rgb_placeholder 108 | 109 | stdout.write("\n Background: %s\n" % bg) 110 | stdout.write(" Foreground: %s\n\n" % fg) 111 | 112 | def show_ansi(self): 113 | """ 114 | Show the 16 ANSI colors (colors 0-15). 115 | 116 | Errors: 117 | TerminalUninitializedError: if this instance's context has 118 | not been entered. 119 | """ 120 | color_order = [0, 1, 3, 2, 6, 4, 5, 7] 121 | 122 | names = [' Black ', ' Red ', ' Green ', ' Yellow ', 123 | ' Blue ', ' Magenta', ' Cyan ', ' White '] 124 | 125 | stdout.write(self.fgcolor('15', 3)) 126 | 127 | for k in range(8): 128 | a = color_order[k] 129 | stdout.write(names[a]) 130 | 131 | stdout.write('\n') 132 | stdout.write(self.fgcolor(None, 3)) 133 | 134 | c = None 135 | for k in range(8): 136 | a = color_order[k] 137 | c = self.hiprint(' [%X/%X] ' % (a, 8 + a), c) 138 | stdout.write('\n') 139 | 140 | self.show_color_table([0, 8], color_order) 141 | 142 | def show_color_cube(self, n): 143 | """ 144 | Show the "RGB cube" (xterm colors 16-231 (256-color) or 16-79 145 | (88-color)). The cube has sides of length 6 or 4 (for 256-color 146 | or 88-color, respectively). 147 | 148 | Arguments: 149 | n: 256 or 88. 150 | 151 | Errors: 152 | TerminalUninitializedError: if this instance's context has 153 | not been entered. 154 | """ 155 | base = {256: 6, 88: 4}[n] 156 | 157 | c = None 158 | c = self.hiprint('[ + ] ', c) 159 | for w in range(base): 160 | c = self.hiprint('[%X] ' % w, c) 161 | stdout.write('\n\n' + self.fgcolor(None, 3)) 162 | 163 | for u in range(base): 164 | for v in range(base): 165 | stdout.write(' '*v) 166 | 167 | x = (u*base + v)*base 168 | self.hiprint(' [%02X] ' % (16 + x)) 169 | stdout.write(self.fgcolor(None, 3)) 170 | 171 | for w in range(base): 172 | self.show_color(x + w + 16) 173 | stdout.write('\n') 174 | stdout.write('\n\n') 175 | 176 | def show_grayscale_ramp(self, end): 177 | """ 178 | Show the "grayscale ramp" (xterm colors 232-255 (256-color) or 179 | 80-87 (88-color)). 180 | 181 | Arguments: 182 | n: 256 or 88. 183 | 184 | Errors: 185 | TerminalUninitializedError: if this instance's context has 186 | not been entered. 187 | """ 188 | start = {256: 232, 88: 80}[end] 189 | n = end - start 190 | 191 | vals = [self.get_color(a) for a in range(start, end)] 192 | 193 | c = None 194 | 195 | c = self.hiprint('[ ', c) 196 | for v in range(n): 197 | c = self.hiprint('%02X ' % (start + v), c) 198 | c = self.hiprint(']\n', c) 199 | 200 | stdout.write('\n ' + self.fgcolor(None, 3)) 201 | 202 | for v in range(n): 203 | stdout.write(' ' + self.block(start + v, 2)) 204 | stdout.write('\n ') 205 | 206 | for u in range(3): 207 | for v in range(n): 208 | stdout.write(' ') 209 | stdout.write(self.fgcolor(start + v, 2)) 210 | stdout.write(vals[v][2*u: 2*(u + 1)]) 211 | stdout.write(self.fgcolor(None, 2)) 212 | stdout.write('\n ') 213 | stdout.write('\n') 214 | 215 | def show_colors(self, n): 216 | """ 217 | Make a table showing colors 0 through n-1. 218 | 219 | Arguments: 220 | n: the number (int) of colors to show. 221 | 222 | Errors: 223 | TerminalUninitializedError: if this instance's context has 224 | not been entered. 225 | """ 226 | self.show_color_table(range(0, n, 8), range(8), n, True) 227 | 228 | def show_color_table(self, rows, cols, stop=-1, label=False): 229 | """ 230 | Make a color table with all possible color indices of the form 231 | rows[k] + cols[j] that are less than `stop` (if `stop` is not 232 | negative). If label is True, then print row and column labels. 233 | 234 | Arguments: 235 | rows, cols: iterable of int.. 236 | stop: if nonnegative, the upper bound (non-inclusive) on the 237 | color indices to display. 238 | label: whether to show row and column labels. 239 | 240 | Errors: 241 | TerminalUninitializedError: if this instance's context has 242 | not been entered. 243 | """ 244 | if label: 245 | self.hiprint('[ + ]') 246 | stdout.write(self.fgcolor(None, 3)) 247 | 248 | for a in cols: 249 | stdout.write(' ' + self.octal(a) + ' ') 250 | stdout.write('\n' + self.fgcolor(None, 1)) 251 | 252 | if label: 253 | stdout.write(' ') 254 | 255 | stdout.write('\n') 256 | 257 | for b in rows: 258 | if label: 259 | stdout.write(self.octal(b) + ' ' + 260 | self.fgcolor(None, 1)) 261 | 262 | for a in cols: 263 | c = a + b 264 | if stop < 0 or c < stop: 265 | self.show_color(b + a) 266 | else: 267 | stdout.write(' ') 268 | stdout.write('\n') 269 | stdout.write('\n') 270 | 271 | def show_color(self, a): 272 | """ 273 | Make a pretty display of color number `a`, showing a block of 274 | that color followed by the 6-character hexadecimal code for the 275 | color. 276 | 277 | Arguments: 278 | a: color index to show. 279 | 280 | Errors: 281 | TerminalUninitializedError: if this instance's context has 282 | not been entered. 283 | """ 284 | stdout.write(' ' + self.block(a) + ' ') 285 | stdout.write(self.fgcolor(a, 2) + (self.get_color(a))) 286 | stdout.write(self.fgcolor(None, 2)) 287 | 288 | def hiprint(self, s, last_color=-1): 289 | """ 290 | Print s to stdout, highlighting digits, brackets, etc. if the 291 | color level allows it. 292 | 293 | Arguments: 294 | s: the string to print. 295 | last_color: the current terminal foreground color. This 296 | should be `None` if no color is set, or the current 297 | color index, or something else (like a negative integer) 298 | if the color isn't known. (The last option is always 299 | safe and will force this function to do the right 300 | thing.) 301 | 302 | Return: the current foreground color, which can be passed as 303 | last_color to the next call if the color isn't changed in 304 | between. 305 | """ 306 | for c in s: 307 | if c == ' ': 308 | color = last_color 309 | else: 310 | color = self.hi[c] 311 | 312 | if color != last_color: 313 | stdout.write(self.fgcolor(color, 3)) 314 | 315 | stdout.write(c) 316 | last_color = color 317 | 318 | return last_color 319 | 320 | def octal(self, x): 321 | """ 322 | Return a base-8 string for the integer x, highlighted if the 323 | color level allows it. 324 | 325 | Arguments: 326 | x: integer to convert. 327 | 328 | Return: string representation, possibly with ANSI color codes. 329 | """ 330 | return (self.fgcolor(self.hi['+'], 3) + '0' 331 | + self.fgcolor(self.hi['0'], 3) + ('%03o' % x)) 332 | 333 | def block(self, c, n=1): 334 | """ 335 | Return a string that prints as a block of color `c` and size `n`. 336 | 337 | Arguments: 338 | c: color index of block. 339 | n: length of block. 340 | 341 | Return: string representation, possibly with ANSI color codes. 342 | """ 343 | return self.bgcolor(c, 1) + ' '*n + self.bgcolor(None, 1) 344 | 345 | # Changing the foreground and background colors. 346 | # 347 | # While the 38;5 and 48;5 SGR codes are less portable than the usual 348 | # 30-37 and 40-47, these codes seem to be fairly widely implemented 349 | # (on X-windows terminals, screen, and tmux) and support the whole 350 | # color range, as opposed to just colors 0-8. They also make it 351 | # very easy to set the background to a given color without needing 352 | # to mess around with bold or reverse video (which are hardly 353 | # portable themselves). This is useful even for the 16 ANSI colors. 354 | 355 | def fgcolor(self, a=None, level=-1): 356 | """ 357 | Return a string designed to set the foreground color to `a` when 358 | printed to the terminal. None means default. 359 | 360 | Arguments: 361 | a: color index to set to, or None to reset to default. 362 | level: minimum colorfulness level for which colors should be 363 | affected. 364 | 365 | Return: ANSI control sequence as string. 366 | """ 367 | if self.color_level >= level: 368 | if a is None: 369 | return self.csi + '39m' 370 | else: 371 | return self.csi + '38;5;' + str(a) + 'm' 372 | else: 373 | return '' 374 | 375 | def bgcolor(self, a=None, level=-1): 376 | """ 377 | Return a string designed to set the background color to `a` when 378 | printed to the terminal. None means default. 379 | 380 | Arguments: 381 | a: color index to set to, or None to reset to default. 382 | level: minimum colorfulness level for which colors should be 383 | affected. 384 | 385 | Return: ANSI control sequence as string. 386 | """ 387 | if self.color_level >= level: 388 | if a is None: 389 | return self.csi + '49m' 390 | else: 391 | return self.csi + '48;5;' + str(a) + 'm' 392 | else: 393 | return '' 394 | 395 | def get_color(self, a): 396 | """ 397 | Return a formatted string representing the given color index, 398 | if possible. 399 | 400 | Arguments: 401 | a: color index to convert. 402 | 403 | Return: the color's hex code, or a placeholder. 404 | 405 | Errors: 406 | TerminalUninitializedError: if this instance's context has 407 | not been entered. 408 | """ 409 | if self.do_query: 410 | c = self.get_indexed_color(a, timeout=self.timeout) 411 | return self.format(c) 412 | else: 413 | return self.rgb_placeholder 414 | 415 | def format(self, c): 416 | """ 417 | Return a formatted string representing RGBAColor instance c. 418 | 419 | Arguments: 420 | c: RGBAColor instance to convert, or None. 421 | 422 | Return: hex code of c, or a placeholder. 423 | """ 424 | if c: 425 | return "%02X%02X%02X" % (int(c.r * 0xffff) // 256, 426 | int(c.g * 0xffff) // 256, 427 | int(c.b * 0xffff) // 256) 428 | else: 429 | return self.rgb_placeholder 430 | -------------------------------------------------------------------------------- /colordemo/terminal_query.py: -------------------------------------------------------------------------------- 1 | # Copyright 2012-2023 Darsh Ranjan, oblique 2 | # 3 | # This file is part of termcolors. 4 | # 5 | # termcolors is free software: you can redistribute it and/or modify 6 | # it under the terms of the GNU General Public License as published by 7 | # the Free Software Foundation, either version 3 of the License, or 8 | # (at your option) any later version. 9 | # 10 | # termcolors is distributed in the hope that it will be useful, but 11 | # WITHOUT ANY WARRANTY; without even the implied warranty of 12 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 | # General Public License for more details. 14 | # 15 | # You should have received a copy of the GNU General Public License 16 | # along with termcolors. If not, see 17 | # . 18 | 19 | import os 20 | import re 21 | import select 22 | import termios 23 | 24 | from .colors import RGBAColor 25 | 26 | ####################################################################### 27 | # Query-related error conditions 28 | 29 | 30 | class TerminalQueryError(Exception): 31 | """ 32 | Base class for the other exceptions. 33 | """ 34 | 35 | def __init__(self, message): 36 | Exception.__init__(self, message) 37 | 38 | 39 | class TerminalSetupError(TerminalQueryError): 40 | """ 41 | We couldn't set up the terminal properly. 42 | """ 43 | 44 | def __init__(self, fd): 45 | TerminalQueryError.__init__( 46 | self, 47 | ("Couldn't set up terminal on file " + 48 | ("descriptor %d" % fd))) 49 | 50 | 51 | class NoResponseError(TerminalQueryError): 52 | """ 53 | The terminal didn't respond, or we were too impatient. 54 | """ 55 | 56 | def __init__(self, q): 57 | TerminalQueryError.__init__( 58 | self, 59 | "Timeout on query " + repr(q)) 60 | 61 | 62 | class TerminalUninitializedError(TerminalQueryError): 63 | """ 64 | Someone tried to do something without setting up the terminal 65 | properly (by calling TerminalQueryContext.__enter__). 66 | """ 67 | 68 | def __init__(self, fd): 69 | TerminalQueryError.__init__( 70 | self, 71 | (("Terminal on file descriptor %d " % fd) + 72 | "not set up")) 73 | 74 | 75 | ######################################################################## 76 | 77 | class TerminalQueryContext(object): 78 | """ 79 | Context manager for terminal RGB queries. 80 | """ 81 | 82 | # Operating system command 83 | osc = "\033]" 84 | 85 | # String terminator 86 | # ("\033\\" is another option, but "\007" seems to be understood by 87 | # more terminals. Terminology, for example, doesn't seem to like 88 | # "\033\\".) 89 | st = "\007" 90 | 91 | # Control sequence introducer 92 | csi = "\033[" 93 | 94 | # ANSI SGR0 95 | reset = csi + 'm' 96 | 97 | def __init__(self, fd=0, screen_forward=False): 98 | """ 99 | Arguments: 100 | fd: open file descriptor referring to the terminal we care 101 | about. The default (0) is almost always correct. 102 | screen_forward: whether to attempt to forward queries 103 | through a screen or tmux session if we are in one. 104 | """ 105 | self.tc_save = None 106 | self.fd = fd 107 | 108 | self.num_errors = 0 109 | 110 | self.screen_forward = screen_forward 111 | 112 | def __enter__(self): 113 | """ 114 | Set up the terminal for queries. 115 | """ 116 | self.tc_save = termios.tcgetattr(self.fd) 117 | 118 | tc = termios.tcgetattr(self.fd) 119 | 120 | # Don't echo the terminal's responses 121 | tc[3] &= ~termios.ECHO 122 | 123 | # Noncanonical mode (i.e., disable buffering on the terminal 124 | # level) 125 | tc[3] &= ~termios.ICANON 126 | 127 | # Make input non-blocking 128 | tc[6][termios.VMIN] = 0 129 | tc[6][termios.VTIME] = 0 130 | 131 | termios.tcsetattr(self.fd, termios.TCSANOW, tc) 132 | 133 | # Check if it succeeded 134 | if termios.tcgetattr(self.fd) != tc: 135 | termios.tcsetattr(self.fd, termios.TCSANOW, self.tc_save) 136 | raise TerminalSetupError(self.fd) 137 | 138 | self.P = select.poll() 139 | self.P.register(self.fd, select.POLLIN) 140 | 141 | return self 142 | 143 | def __exit__(self, exc_type, exc_value, traceback): 144 | """ 145 | Reset the terminal to its original state. 146 | """ 147 | self.flush_input() 148 | 149 | if self.tc_save is not None: 150 | termios.tcsetattr(self.fd, termios.TCSANOW, self.tc_save) 151 | 152 | del self.P 153 | 154 | def get_num_colors(self, timeout=-1): 155 | """ 156 | Attempt to determine the number of colors we are able to query 157 | from the terminal. A larger timeout is safer but will cause this 158 | function to take proportionally more time. 159 | 160 | Arguments: 161 | timeout: millisecond timeout, same interpretation as in 162 | self.guarded_query. 163 | 164 | Return: integer number of colors that are queryable. 165 | 166 | Errors: 167 | TerminalUninitializedError: if this instance's context has 168 | not been entered. 169 | """ 170 | # We won't count failed queries in this function, since we're 171 | # guaranteed to fail a few. 172 | num_errors = self.num_errors 173 | 174 | if not self.get_indexed_color(0, timeout): 175 | return 0 176 | 177 | a = 0 178 | b = 1 179 | while self.get_indexed_color(b, timeout): 180 | a = b 181 | b += b 182 | 183 | while b - a > 1: 184 | c = (a + b) >> 1 185 | if self.get_indexed_color(c, timeout): 186 | a = c 187 | else: 188 | b = c 189 | 190 | self.num_errors = num_errors 191 | return b 192 | 193 | def get_all_indexed_colors(self, limit=-1, timeout=-1): 194 | """ 195 | Query as many indexed RGB values as possible up to `limit` 196 | and return them all in a list. 197 | 198 | Arguments: 199 | limit: maximum number of colors to query, if nonnegative. 200 | Negative values disable the limit. 201 | timeout: millisecond timeout, same interpretation as in 202 | self.guarded_query. 203 | 204 | Return: list of RGBAColor instances. 205 | 206 | Errors: 207 | TerminalUninitializedError: if this instance's context has 208 | not been entered. 209 | """ 210 | colors = [] 211 | 212 | k = 0 213 | while limit < 0 or k < limit: 214 | c = self.get_indexed_color(k, timeout) 215 | if c: 216 | colors.append(c) 217 | k += 1 218 | else: 219 | if limit < 0: 220 | self.num_errors -= 1 221 | break 222 | 223 | return colors 224 | 225 | # Wrappers for xterm & urxvt operating system controls. 226 | # 227 | # These codes are all common to xterm and urxvt. Their responses 228 | # aren't always in the same format (xterm generally being more 229 | # consistent), but the regular expression used to parse the 230 | # responses is general enough to work for both. 231 | # 232 | # Note: none of these functions is remotely thread-safe. 233 | 234 | def get_fg(self, timeout=-1): 235 | """ 236 | Get the terminal's foreground (text) color. 237 | 238 | Arguments: 239 | timeout: millisecond timeout, same interpretation as in 240 | self.guarded_query. 241 | 242 | Return: RGBAColor instance. 243 | 244 | Errors: 245 | TerminalUninitializedError: if this instance's context has 246 | not been entered. 247 | """ 248 | return self.rgb_query([10], timeout) 249 | 250 | def get_bg(self, timeout=-1): 251 | """ 252 | Get the terminal's background color. 253 | 254 | Arguments: 255 | timeout: millisecond timeout, same interpretation as in 256 | self.guarded_query. 257 | 258 | Return: RGBAColor instance. 259 | 260 | Errors: 261 | TerminalUninitializedError: if this instance's context has 262 | not been entered. 263 | """ 264 | return self.rgb_query([11], timeout) 265 | 266 | def get_indexed_color(self, a, timeout=-1): 267 | """ 268 | Get color number `a`. 269 | 270 | Arguments: 271 | a: color index to query. 272 | timeout: millisecond timeout, same interpretation as in 273 | self.guarded_query. 274 | 275 | Return: RGBAColor instance. 276 | 277 | Errors: 278 | TerminalUninitializedError: if this instance's context has 279 | not been entered. 280 | """ 281 | return self.rgb_query([4, a], timeout) 282 | 283 | def flush_input(self): 284 | """ 285 | Discard any input that can be read at this moment. 286 | """ 287 | while self.P.poll(0): 288 | os.read(self.fd, 4096) 289 | 290 | # Patterns matching unsigned decimal and hexadecimal integer 291 | # literals 292 | ndec = "[0-9]+" 293 | nhex = "[0-9a-fA-F]+" 294 | 295 | # The "guard" query and its response pattern. 296 | q_guard = csi + "6n" 297 | 298 | str_guard = "(.*)\033\\[{ndec};{ndec}R".format(**vars()) 299 | re_guard = re.compile(str_guard) 300 | 301 | # This is what we expect the terminal's response to a query for a 302 | # color to look like. If we didn't care about urxvt, we could get 303 | # away with a simpler implementation here, since xterm and vte seem 304 | # to give pretty consistent and systematic responses. 305 | str_rgb = ("\033\\]({ndec};)+rgba?:" + 306 | "({nhex})/({nhex})/({nhex})(/({nhex}))?" 307 | ).format(**vars()) 308 | re_rgb = re.compile(str_rgb) 309 | 310 | def rgb_query(self, q, timeout=-1): 311 | r""" 312 | Query a color-valued terminal parameter. 313 | 314 | See 315 | http://invisible-island.net/xterm/ctlseqs/ctlseqs.html 316 | 317 | ("Operating System Controls") to see the various queries 318 | supported by xterm. Urxvt supports some, but not all, of them, 319 | and has a number of its own (see man -s7 urxvt). 320 | 321 | self.__enter__ must be called prior to calling this function, or 322 | TerminalUninitializedError will be raised. 323 | 324 | Arguments: 325 | q: The query code as a sequence of nonnegative integers, 326 | i.e., [q0, q1, ...] if the escape sequence in 327 | pseudo-Python is 328 | 329 | "\033]{q0};{q1};...;?\007" 330 | 331 | timeout: millisecond timeout, same interpretation as in 332 | self.guarded_query. 333 | 334 | Return: the color value as an RGBAColor instance. If the 335 | terminal provides an unparseable (or no) response, then None 336 | will be returned. 337 | 338 | Errors: 339 | TerminalUninitializedError: if this instance's context has 340 | not been entered. 341 | """ 342 | query = (self.osc + 343 | ';'.join([str(k) for k in q]) + ';?' + 344 | self.st) 345 | 346 | try: 347 | response = self.guarded_query(query, timeout) 348 | except NoResponseError: 349 | return None 350 | 351 | m = self.re_rgb.match(response) 352 | 353 | if not m: 354 | self.num_errors += 1 355 | return None 356 | 357 | # (possibly overkill, since all terminals that reply seem to 358 | # give 4-digit RGB components, in which case `nd' is 4 and `u' 359 | # is 0xffff) 360 | nd = len(m.group(4)) 361 | u = (1 << (nd << 2)) - 1 362 | 363 | alpha = float(int(m.group(6), 16))/u if m.group(6) else 1.0 364 | (r, g, b) = (int(m.group(i), 16)/u for i in [2, 3, 4]) 365 | 366 | return RGBAColor(r, g, b, alpha) 367 | 368 | # If a terminal sees an escape sequence it doesn't like, it will 369 | # simply ignore it. Also, it's hard to predict how long a terminal 370 | # will take to respond to a query it does like. However, some 371 | # escape sequences, like "\033[6n", will produce a predictable 372 | # response on *most* (but not all) terminals, and this fact can be 373 | # used to test for the absence of a response to a particular query 374 | # on such terminals. 375 | 376 | def guarded_query(self, q, timeout=-1, flush=True): 377 | """ 378 | Send the terminal query string `q` and return the terminal's 379 | response. 380 | 381 | Arguments: 382 | q: the query string to send to the terminal. 383 | timeout: how many milliseconds to wait for a response, a 384 | negative number meaning "infinite". 385 | flush: whether to discard waiting input before sending the 386 | query. It usually makes sense to do this, but note that 387 | the terminal may still send seemingly unsolicited data 388 | (possibly in response to an earlier query) after the 389 | input is flushed, so flushing the input does not 390 | provide any guarantees. 391 | 392 | Return: The terminal's response to the query as a string. 393 | 394 | Errors: 395 | NoResponseError: if the query times out. 396 | TerminalUninitializedError: if this instance's context has 397 | not been entered. 398 | """ 399 | if not hasattr(self, "P"): 400 | raise TerminalUninitializedError(self.fd) 401 | 402 | query = q + self.q_guard 403 | 404 | if self.screen_forward: 405 | if os.getenv("TMUX"): 406 | # We seem to be in a tmux session. tmux can be used 407 | # like a proxy to send queries to the actual terminal. 408 | # The format of proxy query is: 409 | # 410 | # \033Ptmux;{original query}\0\033\\ 411 | # 412 | # Also, all the \033 of the original query must be 413 | # escaped with \033. 414 | query = ("\033Ptmux;" + 415 | query.replace("\033", "\033\033") + 416 | "\0\033\\") 417 | 418 | elif os.getenv("STY"): 419 | # We seem to be in a screen session. Like tmux, screen 420 | # can also send queries through to the terminal. Unlike 421 | # tmux, \033 does not need to be (cannot be???) escaped. 422 | # 423 | # XXX Is there a better way to "escape" string 424 | # terminators? 425 | query = ("\033P" + 426 | query.replace("\033\\", "\033\033\\\033P\\") + 427 | "\033\\") 428 | 429 | if flush: 430 | self.flush_input() 431 | 432 | os.write(self.fd, query.encode()) 433 | 434 | response = "" 435 | 436 | while self.P.poll(timeout): 437 | response += os.read(self.fd, 4096).decode() 438 | m = self.re_guard.match(response) 439 | if m: 440 | return m.group(1) 441 | else: 442 | self.num_errors += 1 443 | raise NoResponseError(query) 444 | -------------------------------------------------------------------------------- /COPYING: -------------------------------------------------------------------------------- 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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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 | 635 | Copyright (C) 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 | Copyright (C) 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 | --------------------------------------------------------------------------------