[PATCH] builtin-grep: workaround for non GNU grep.
Some implementations do not know what to do with -H; define NO_H_OPTION_IN_GREP when you build git if your grep lacks -H.
Most of the time, it can be worked around by prepending /dev/null to the argument list, but that causes -L and -c to slightly misbehave (they both expose /dev/null is given), so when these options are given, do not run external grep that does not understand -H.
Signed-off-by: Junio C Hamano <junkio@cox.net>
---
Junio C Hamano <junkio@cox.net> writes:
> But I think this approach breaks -L; I do not think Solaris
> supports -L, so it does not matter there, but on platforms that
> knows how to do -L it does.
So this is an updated version. I am not proud of the handling
of the new Makefile variable, although I like the C code that
does not need #ifdef thanks to it.
Makefile | 11 +++++++++++
builtin-grep.c | 22 +++++++++++++++++++---
2 files changed, 30 insertions(+), 3 deletions(-)
diff --git a/Makefile b/Makefile
index 9ba608c..c67108d 100644
--- a/Makefile
+++ b/Makefile
@@ -46,6 +46,8 @@ # Patrick Mauritz).
#
# Define NO_MMAP if you want to avoid mmap.
#
+# Define NO_H_OPTION_IN_GREP if your grep does not understand -H.
+#
# Define WITH_OWN_SUBPROCESS_PY if you want to use with python 2.3.
#
# Define NO_IPV6 if you lack IPv6 support and getaddrinfo().
@@ -444,6 +446,12 @@ ifdef NO_ACCURATE_DIFF
ALL_CFLAGS += -DNO_ACCURATE_DIFF
endif
+ifdef NO_H_OPTION_IN_GREP
+ NO_H_OPTION_IN_GREP=1
+else
+ NO_H_OPTION_IN_GREP=0
+endif
+
# Shell quote (do not use $(call) to accomodate ancient setups);
SHA1_HEADER_SQ = $(subst ','\'',$(SHA1_HEADER))
@@ -526,6 +534,9 @@ git$X git.spec \
%.o: %.S
$(CC) -o $*.o -c $(ALL_CFLAGS) $<
+builtin-grep.o: builtin-grep.c
+ $(CC) -o $*.o -c $(ALL_CFLAGS) -DNO_H_OPTION_IN_GREP=$(NO_H_OPTION_IN_GREP) $<
+
exec_cmd.o: exec_cmd.c
$(CC) -o $*.o -c $(ALL_CFLAGS) '-DGIT_EXEC_PATH="$(gitexecdir_SQ)"' $<
diff --git a/builtin-grep.c b/builtin-grep.c
index 66111de..36512d8 100644
--- a/builtin-grep.c
+++ b/builtin-grep.c
@@ -453,7 +453,6 @@ static int external_grep(struct grep_opt
len = nr = 0;
push_arg("grep");
- push_arg("-H");
if (opt->fixed)
push_arg("-F");
if (opt->linenum)
@@ -503,7 +502,13 @@ static int external_grep(struct grep_opt
push_arg("-e");
push_arg(p->pattern);
}
- push_arg("--");
+
+ if (NO_H_OPTION_IN_GREP)
+ push_arg("/dev/null");
+ else {
+ push_arg("-H");
+ push_arg("--");
+ }
hit = 0;
argc = nr;
@@ -535,8 +540,19 @@ #ifdef __unix__
* Use the external "grep" command for the case where
* we grep through the checked-out files. It tends to
* be a lot more optimized
+ *
+ * Some grep implementations do not understand -H nor --
+ * but /dev/null can be used as a substitution in most
+ * cases.
+ *
+ * However -L and -c would slightly misbehave (-L would
+ * list /dev/null as a hit, and -c would report 0 hits
+ * from /dev/null); so do not use the external one on
+ * such platforms.
*/
- if (!cached) {
+ if (!cached &&
+ (!NO_H_OPTION_IN_GREP ||
+ (!opt->count && !opt->unmatch_name_only))) {
hit = external_grep(opt, paths, cached);
if (hit >= 0)
return hit;
--
1.3.3.g8a24
