Allow custom "comment char"

Some users do want to write a line that begin with a pound sign, #,
in their commit log message.  Many tracking system recognise
a token of #<bugid> form, for example.

The support we offer these use cases is not very friendly to the end
users.  They have a choice between

 - Don't do it.  Avoid such a line by rewrapping or indenting; and

 - Use --cleanup=whitespace but remove all the hint lines we add.

Give them a way to set a custom comment char, e.g.

    $ git -c core.commentchar="%" commit

so that they do not have to do either of the two workarounds.

[jc: although I started the topic, all the tests and documentation
updates, many of the call sites of the new strbuf_add_commented_*()
functions, and the change to git-submodule.sh scripted Porcelain are
from Ralf.]

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/strbuf.h b/strbuf.h
index ecae4e2..958822c 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -110,6 +110,8 @@ extern void strbuf_remove(struct strbuf *, size_t pos, size_t len);
 extern void strbuf_splice(struct strbuf *, size_t pos, size_t len,
                           const void *, size_t);
 
+extern void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size);
+
 extern void strbuf_add(struct strbuf *, const void *, size_t);
 static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
 	strbuf_add(sb, s, strlen(s));
@@ -131,6 +133,8 @@ extern void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *
 
 __attribute__((format (printf,2,3)))
 extern void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
+__attribute__((format (printf, 2, 3)))
+extern void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...);
 __attribute__((format (printf,2,0)))
 extern void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap);