GUACAMOLE-278: Handle xterm 256-color SGR sequences.
Project: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/repo Commit: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/commit/87fba523 Tree: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/tree/87fba523 Diff: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/diff/87fba523 Branch: refs/heads/master Commit: 87fba523ee668c8f7f81d36d2df5c3c560aff8c9 Parents: 11bf6f0 Author: Michael Jumper <[email protected]> Authored: Sun Apr 23 12:53:47 2017 -0700 Committer: Michael Jumper <[email protected]> Committed: Sun Apr 23 13:24:13 2017 -0700 ---------------------------------------------------------------------- src/terminal/terminal_handlers.c | 156 +++++++++++++++++++++++++++++++++- 1 file changed, 152 insertions(+), 4 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/blob/87fba523/src/terminal/terminal_handlers.c ---------------------------------------------------------------------- diff --git a/src/terminal/terminal_handlers.c b/src/terminal/terminal_handlers.c index a4e514c..ecb60e9 100644 --- a/src/terminal/terminal_handlers.c +++ b/src/terminal/terminal_handlers.c @@ -435,6 +435,133 @@ static bool* __guac_terminal_get_flag(guac_terminal* term, int num, char private } +/** + * Parses an xterm SGR sequence specifying the RGB values of a color. + * + * @param argc + * The number of arguments within the argv array. + * + * @param argv + * The SGR arguments to parse, with the first relevant argument the + * red component of the RGB color. + * + * @param color + * The guac_terminal_color structure which should receive the parsed + * color values. + * + * @return + * The number of arguments parsed, or zero if argv does not contain + * enough elements to represent an RGB color. + */ +static int guac_terminal_parse_xterm256_rgb(int argc, const int* argv, + guac_terminal_color* color) { + + /* RGB color palette entries require three arguments */ + if (argc < 3) + return 0; + + /* Store RGB components */ + color->red = (uint8_t) argv[0]; + color->green = (uint8_t) argv[1]; + color->blue = (uint8_t) argv[2]; + + /* Color is not from the palette */ + color->palette_index = -1; + + /* Done */ + return 3; + +} + +/** + * Parses an xterm SGR sequence specifying the index of a color within the + * 256-color palette. + * + * @param argc + * The number of arguments within the argv array. + * + * @param argv + * The SGR arguments to parse, with the first relevant argument being + * the index of the color. + * + * @param color + * The guac_terminal_color structure which should receive the parsed + * color values. + * + * @return + * The number of arguments parsed, or zero if the palette index is + * out of range or absent. + */ +static int guac_terminal_parse_xterm256_index(int argc, const int* argv, + guac_terminal_color* color) { + + /* 256-color palette entries require only one argument */ + if (argc < 1) + return 0; + + /* Verify palette index bounds */ + int index = argv[0]; + if (index < 0 || index > 255) + return 0; + + /* Copy palette entry */ + *color = guac_terminal_palette[index]; + + /* Done */ + return 1; + +} + +/** + * Parses an xterm SGR sequence specifying the index of a color within the + * 256-color palette, or specfying the RGB values of a color. The number of + * arguments required by these sequences varies. If a 256-color sequence is + * recognized, the number of arguments parsed is returned. + * + * @param argc + * The number of arguments within the argv array. + * + * @param argv + * The SGR arguments to parse, with the first relevant argument being + * the first element of the array. In the case of an xterm 256-color + * SGR sequence, the first element here will be either 2, for an + * RGB color, or 5, for a 256-color palette index. All other values + * are invalid and will not be parsed. + * + * @param color + * The guac_terminal_color structure which should receive the parsed + * color values. + * + * @return + * The number of arguments parsed, or zero if argv does not point to + * the first element of an xterm 256-color SGR sequence. + */ +static int guac_terminal_parse_xterm256(int argc, const int* argv, + guac_terminal_color* color) { + + /* All 256-color codes must have at least a type */ + if (argc < 1) + return 0; + + switch (argv[0]) { + + /* RGB */ + case 2: + return guac_terminal_parse_xterm256_rgb( + argc - 1, &argv[1], color) + 1; + + /* Palette index */ + case 5: + return guac_terminal_parse_xterm256_index( + argc - 1, &argv[1], color) + 1; + + } + + /* Invalid type */ + return 0; + +} + int guac_terminal_csi(guac_terminal* term, unsigned char c) { /* CSI function arguments */ @@ -783,11 +910,27 @@ int guac_terminal_csi(guac_terminal* term, unsigned char c) { term->current_attributes.foreground = guac_terminal_palette[value - 30]; - /* Underscore on, default foreground */ + /* Underscore on, default foreground OR 256-color + * foreground */ else if (value == 38) { - term->current_attributes.underscore = true; - term->current_attributes.foreground = - term->default_char.attributes.foreground; + + /* Attempt to set foreground with 256-color entry */ + int xterm256_length = + guac_terminal_parse_xterm256(argc - 1, &argv[i + 1], + &term->current_attributes.foreground); + + /* If valid 256-color entry, foreground has been set */ + if (xterm256_length > 0) + i += xterm256_length; + + /* Otherwise interpret as underscore and default + * foreground */ + else { + term->current_attributes.underscore = true; + term->current_attributes.foreground = + term->default_char.attributes.foreground; + } + } /* Underscore off, default foreground */ @@ -802,6 +945,11 @@ int guac_terminal_csi(guac_terminal* term, unsigned char c) { term->current_attributes.background = guac_terminal_palette[value - 40]; + /* 256-color background */ + else if (value == 48) + i += guac_terminal_parse_xterm256(argc - 1, &argv[i + 1], + &term->current_attributes.background); + /* Reset background */ else if (value == 49) term->current_attributes.background =
