diff --git a/Documentation/config/sideband.txt b/Documentation/config/sideband.txt index 3fb5045cd7..b55c73726f 100644 --- a/Documentation/config/sideband.txt +++ b/Documentation/config/sideband.txt @@ -1,5 +1,17 @@ sideband.allowControlCharacters:: By default, control characters that are delivered via the sideband - are masked, to prevent potentially unwanted ANSI escape sequences - from being sent to the terminal. Use this config setting to override - this behavior. + are masked, except ANSI color sequences. This prevents potentially + unwanted ANSI escape sequences from being sent to the terminal. Use + this config setting to override this behavior: ++ +-- + `default`:: + `color`:: + Allow ANSI color sequences, line feeds and horizontal tabs, + but mask all other control characters. This is the default. + `false`:: + Mask all control characters other than line feeds and + horizontal tabs. + `true`:: + Allow all control characters to be sent to the terminal. +-- diff --git a/sideband.c b/sideband.c index 1499587ff6..f4bcdcaf9b 100644 --- a/sideband.c +++ b/sideband.c @@ -25,7 +25,12 @@ static struct keyword_entry keywords[] = { { "error", GIT_COLOR_BOLD_RED }, }; -static int allow_control_characters; +static enum { + ALLOW_NO_CONTROL_CHARACTERS = 0, + ALLOW_ANSI_COLOR_SEQUENCES = 1<<0, + ALLOW_DEFAULT_ANSI_SEQUENCES = ALLOW_ANSI_COLOR_SEQUENCES, + ALLOW_ALL_CONTROL_CHARACTERS = 1<<1, +} allow_control_characters = ALLOW_ANSI_COLOR_SEQUENCES; /* Returns a color setting (GIT_COLOR_NEVER, etc). */ static int use_sideband_colors(void) @@ -40,8 +45,26 @@ static int use_sideband_colors(void) if (use_sideband_colors_cached >= 0) return use_sideband_colors_cached; - git_config_get_bool("sideband.allowcontrolcharacters", - &allow_control_characters); + switch (git_config_get_maybe_bool("sideband.allowcontrolcharacters", &i)) { + case 0: /* Boolean value */ + allow_control_characters = i ? ALLOW_ALL_CONTROL_CHARACTERS : + ALLOW_NO_CONTROL_CHARACTERS; + break; + case -1: /* non-Boolean value */ + if (git_config_get_string_tmp("sideband.allowcontrolcharacters", + &value)) + ; /* huh? `get_maybe_bool()` returned -1 */ + else if (!strcmp(value, "default")) + allow_control_characters = ALLOW_DEFAULT_ANSI_SEQUENCES; + else if (!strcmp(value, "color")) + allow_control_characters = ALLOW_ANSI_COLOR_SEQUENCES; + else + warning(_("unrecognized value for `sideband." + "allowControlCharacters`: '%s'"), value); + break; + default: + break; /* not configured */ + } if (!git_config_get_string_tmp(key, &value)) use_sideband_colors_cached = git_config_colorbool(key, value); @@ -70,9 +93,41 @@ void list_config_color_sideband_slots(struct string_list *list, const char *pref list_config_item(list, prefix, keywords[i].keyword); } +static int handle_ansi_color_sequence(struct strbuf *dest, const char *src, int n) +{ + int i; + + /* + * Valid ANSI color sequences are of the form + * + * ESC [ [ [; ]*] m + * + * These are part of the Select Graphic Rendition sequences which + * contain more than just color sequences, for more details see + * https://en.wikipedia.org/wiki/ANSI_escape_code#SGR. + */ + + if (allow_control_characters != ALLOW_ANSI_COLOR_SEQUENCES || + n < 3 || src[0] != '\x1b' || src[1] != '[') + return 0; + + for (i = 2; i < n; i++) { + if (src[i] == 'm') { + strbuf_add(dest, src, i + 1); + return i; + } + if (!isdigit(src[i]) && src[i] != ';') + break; + } + + return 0; +} + static void strbuf_add_sanitized(struct strbuf *dest, const char *src, int n) { - if (allow_control_characters) { + int i; + + if (allow_control_characters == ALLOW_ALL_CONTROL_CHARACTERS) { strbuf_add(dest, src, n); return; } @@ -81,6 +136,9 @@ static void strbuf_add_sanitized(struct strbuf *dest, const char *src, int n) for (; n && *src; src++, n--) { if (!iscntrl(*src) || *src == '\t' || *src == '\n') { strbuf_addch(dest, *src); + } else if ((i = handle_ansi_color_sequence(dest, src, n))) { + src += i; + n -= i; } else { strbuf_addch(dest, '^'); strbuf_addch(dest, *src == 0x7f ? '?' : 0x40 + *src); diff --git a/t/t5409-colorize-remote-messages.sh b/t/t5409-colorize-remote-messages.sh index e8067df591..f34977b332 100755 --- a/t/t5409-colorize-remote-messages.sh +++ b/t/t5409-colorize-remote-messages.sh @@ -101,7 +101,7 @@ test_expect_success 'fallback to color.ui' ' test_expect_success 'disallow (color) control sequences in sideband' ' write_script .git/color-me-surprised <<-\EOF && - printf "error: Have you \\033[31mread\\033[m this?\\n" >&2 + printf "error: Have you \\033[31mread\\033[m this?\\a\\n" >&2 exec "$@" EOF test_config_global uploadPack.packObjectsHook ./color-me-surprised && @@ -109,12 +109,24 @@ test_expect_success 'disallow (color) control sequences in sideband' ' git clone --no-local . throw-away 2>stderr && test_decode_color decoded && + test_grep RED decoded && + test_grep "\\^G" stderr && + tr -dc "\\007" actual && + test_must_be_empty actual && + + rm -rf throw-away && + git -c sideband.allowControlCharacters=false \ + clone --no-local . throw-away 2>stderr && + test_decode_color decoded && test_grep ! RED decoded && + test_grep "\\^G" stderr && rm -rf throw-away && git -c sideband.allowControlCharacters clone --no-local . throw-away 2>stderr && test_decode_color decoded && - test_grep RED decoded + test_grep RED decoded && + tr -dc "\\007" actual && + test_file_not_empty actual ' test_done