blame: handle broken commit headers gracefully

split_ident_line() can leave us with the pointers date_begin, date_end,
tz_begin and tz_end all set to NULL.  Check them before use and supply
the same fallback values as in the case of a negative return code from
split_ident_line().

The "(unknown)" is not actually shown in the output, though, because it
will be converted to a number (zero) eventually.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/blame.c b/builtin/blame.c
index 86100e96627e4f839fb5b627bc09ed4264c36176..77707819afa03703b3ee110345a79eec3d3d9d6f 100644 (file)
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -1375,10 +1375,15 @@ static void get_ac_line(const char *inbuf, const char *what,
        maillen = ident.mail_end - ident.mail_begin;
        mailbuf = ident.mail_begin;
 
-       *time = strtoul(ident.date_begin, NULL, 10);
+       if (ident.date_begin && ident.date_end)
+               *time = strtoul(ident.date_begin, NULL, 10);
+       else
+               *time = 0;
 
-       len = ident.tz_end - ident.tz_begin;
-       strbuf_add(tz, ident.tz_begin, len);
+       if (ident.tz_begin && ident.tz_end)
+               strbuf_add(tz, ident.tz_begin, ident.tz_end - ident.tz_begin);
+       else
+               strbuf_addstr(tz, "(unknown)");
 
        /*
         * Now, convert both name and e-mail using mailmap