git.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] help: colorize man pages
@ 2021-05-18  1:01 Felipe Contreras
  2021-05-18  1:19 ` brian m. carlson
  0 siblings, 1 reply; 33+ messages in thread
From: Felipe Contreras @ 2021-05-18  1:01 UTC (permalink / raw)
  To: git
  Cc: Ævar Arnfjörð Bjarmason, Junio C Hamano,
	Randall S. Becker, Felipe Contreras

Our man pages don't contain many useful colors (just blue links),
moreover, many people have groff SGR disabled, so they don't see any
colors with man pages.

We can set LESS_TERMCAP variables to render bold and underlined text
with colors in the pager; a common trick[1].

Bold is rendered as red, underlined as blue, and standout (messages and
highlighted search) as inverse magenta.

This only works when the pager is less, and the color.pager
configuration is enabled, as well as color.ui.

[1] https://unix.stackexchange.com/questions/119/colors-in-man-pages/147

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
 builtin/help.c | 27 ++++++++++++++++++++++++++-
 color.h        |  1 +
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/builtin/help.c b/builtin/help.c
index bb339f0fc8..0119e833a8 100644
--- a/builtin/help.c
+++ b/builtin/help.c
@@ -11,6 +11,7 @@
 #include "config-list.h"
 #include "help.h"
 #include "alias.h"
+#include "color.h"
 
 #ifndef DEFAULT_HELP_FORMAT
 #define DEFAULT_HELP_FORMAT "man"
@@ -253,10 +254,33 @@ static void exec_man_konqueror(const char *path, const char *page)
 	}
 }
 
+static void colorize_man(void)
+{
+	if (!pager_use_color || !want_color(GIT_COLOR_UNKNOWN))
+		return;
+
+	/* Disable groff colors */
+	setenv("GROFF_NO_SGR", "1", 0);
+
+	/* Bold */
+	setenv("LESS_TERMCAP_md", GIT_COLOR_BOLD_RED, 0);
+	setenv("LESS_TERMCAP_me", GIT_COLOR_RESET, 0);
+
+	/* Underline */
+	setenv("LESS_TERMCAP_us", GIT_COLOR_BLUE GIT_COLOR_UNDERLINE, 0);
+	setenv("LESS_TERMCAP_ue", GIT_COLOR_RESET, 0);
+
+	/* Standout */
+	setenv("LESS_TERMCAP_so", GIT_COLOR_MAGENTA GIT_COLOR_REVERSE, 0);
+	setenv("LESS_TERMCAP_se", GIT_COLOR_RESET, 0);
+}
+
 static void exec_man_man(const char *path, const char *page)
 {
 	if (!path)
 		path = "man";
+
+	colorize_man();
 	execlp(path, "man", page, (char *)NULL);
 	warning_errno(_("failed to exec '%s'"), path);
 }
@@ -264,6 +288,7 @@ static void exec_man_man(const char *path, const char *page)
 static void exec_man_cmd(const char *cmd, const char *page)
 {
 	struct strbuf shell_cmd = STRBUF_INIT;
+	colorize_man();
 	strbuf_addf(&shell_cmd, "%s %s", cmd, page);
 	execl(SHELL_PATH, SHELL_PATH, "-c", shell_cmd.buf, (char *)NULL);
 	warning(_("failed to exec '%s'"), cmd);
@@ -372,7 +397,7 @@ static int git_help_config(const char *var, const char *value, void *cb)
 	if (starts_with(var, "man."))
 		return add_man_viewer_info(var, value);
 
-	return git_default_config(var, value, cb);
+	return git_color_default_config(var, value, cb);
 }
 
 static struct cmdnames main_cmds, other_cmds;
diff --git a/color.h b/color.h
index 98894d6a17..d012add4e8 100644
--- a/color.h
+++ b/color.h
@@ -51,6 +51,7 @@ struct strbuf;
 #define GIT_COLOR_FAINT		"\033[2m"
 #define GIT_COLOR_FAINT_ITALIC	"\033[2;3m"
 #define GIT_COLOR_REVERSE	"\033[7m"
+#define GIT_COLOR_UNDERLINE	"\033[4m"
 
 /* A special value meaning "no color selected" */
 #define GIT_COLOR_NIL "NIL"
-- 
2.31.1


^ permalink raw reply	[flat|nested] 33+ messages in thread

end of thread, other threads:[~2021-05-23 14:48 UTC | newest]

Thread overview: 33+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-05-18  1:01 [PATCH] help: colorize man pages Felipe Contreras
2021-05-18  1:19 ` brian m. carlson
2021-05-18  3:22   ` Felipe Contreras
2021-05-18 23:49     ` brian m. carlson
2021-05-19  1:08       ` Junio C Hamano
2021-05-19  2:07         ` brian m. carlson
2021-05-19  6:09           ` Junio C Hamano
2021-05-19  8:41             ` Ævar Arnfjörð Bjarmason
2021-05-19 10:36               ` Felipe Contreras
2021-05-21  0:58               ` brian m. carlson
2021-05-21 18:09                 ` Felipe Contreras
2021-05-21 19:48                   ` Igor Djordjevic
2021-05-21 21:20                     ` Felipe Contreras
2021-05-21 22:10                       ` Igor Djordjevic
2021-05-21 23:04                         ` Felipe Contreras
2021-05-22 18:38                           ` Igor Djordjevic
2021-05-22 21:48                             ` Felipe Contreras
2021-05-23 11:25                               ` Igor Djordjevic
2021-05-23 14:48                                 ` Felipe Contreras
2021-05-21 22:47                     ` Igor Djordjevic
2021-05-21 23:32                     ` Junio C Hamano
2021-05-19  9:26       ` Ævar Arnfjörð Bjarmason
2021-05-19 10:10         ` Jeff King
2021-05-19 11:45           ` Felipe Contreras
2021-05-19 11:19         ` Felipe Contreras
2021-05-19 12:21           ` Felipe Contreras
2021-05-20  1:55         ` brian m. carlson
2021-05-20  2:23           ` Junio C Hamano
2021-05-20  3:05             ` Felipe Contreras
2021-05-20  3:28               ` Junio C Hamano
2021-05-20  3:48                 ` Felipe Contreras
2021-05-20  2:45           ` Felipe Contreras
2021-05-19 10:25       ` Felipe Contreras

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).