[PATCH 1/4] rev-parse: exit with non-zero status if ref@{n} is not valid.

[Jon Seymour <jon.seymour@gmail.com>]

>From Junio's e-mail:

"The current behaviour of ref@{...} syntax parser is suboptimal:

    $ git rev-parse --verify jch@{99999}; echo $?
    warning: Log for 'jch' only has 1368 entries.
    cfb88e9a8d4926b0011ae2dd67e1f57a98f4b768
    0

It even knows that it is running off the cut-off point; it should just
cause the caller to notice that fact.  I don't think changing it to error
out should cause any harm to existing callers."

This commit is based on a patch suggested by Junio.

Note that the error message reporting the bad log reference
is printed twice if --verify is not specified because
the function is called from two different paths. This is
fixed in subsequent commits.

Signed-off-by: Jon Seymour <jon.seymour@gmail.com>
---
 sha1_name.c |   21 ++++++++++++---------
 1 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/sha1_name.c b/sha1_name.c
index 4af94fa..82ad0f9 100644
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -342,7 +342,7 @@ static int get_sha1_1(const char *name, int len, unsigned char *sha1);
 
 static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 {
-	static const char *warning = "warning: refname '%.*s' is ambiguous.\n";
+	static const char *warn_msg = "warning: refname '%.*s' is ambiguous.";
 	char *real_ref = NULL;
 	int refs_found = 0;
 	int at, reflog_len;
@@ -390,7 +390,7 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 		return -1;
 
 	if (warn_ambiguous_refs && refs_found > 1)
-		fprintf(stderr, warning, len, str);
+		fprintf(stderr, warn_msg, len, str);
 
 	if (reflog_len) {
 		int nth, i;
@@ -426,14 +426,17 @@ static int get_sha1_basic(const char *str, int len, unsigned char *sha1)
 		if (read_ref_at(real_ref, at_time, nth, sha1, NULL,
 				&co_time, &co_tz, &co_cnt)) {
 			if (at_time)
-				fprintf(stderr,
-					"warning: Log for '%.*s' only goes "
-					"back to %s.\n", len, str,
+				warning("Log for '%.*s' only goes "
+					"back to %s.", len, str,
 					show_date(co_time, co_tz, DATE_RFC2822));
-			else
-				fprintf(stderr,
-					"warning: Log for '%.*s' only has "
-					"%d entries.\n", len, str, co_cnt);
+			else {
+				error("Log for '%.*s' only has %d entries.",
+					len,
+					str,
+					co_cnt);
+				free(real_ref);
+				return -1;
+			}
 		}
 	}
 
-- 
1.7.2.1.156.gf148c