config: arbitrary number of matches for --unset and --replace-all

git-config used a static match array to hold the matches we want to
unset/replace when using --unset or --replace-all.  Use a
variable-sized array instead.

This in particular fixes the symptoms git-svn had when storing large
numbers of svn-remote.*.added-placeholder entries in the config file.

While the tests are rather more paranoid than just --unset and
--replace-all, the other operations already worked.  Indeed git-svn's
usage only breaks the first time *after* creating so many entries,
when it wants to unset and re-add them all.

Reported-by: Jess Hottenstein <jess.hottenstein@gmail.com>
Signed-off-by: Thomas Rast <tr@thomasrast.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 13 insertions, 6 deletions

diff --git a/config.c b/config.c
index 9f9bf0c..a1e80da 100644
--- a/config.c
+++ b/config.c
@@ -1160,15 +1160,14 @@ int git_config(config_fn_t fn, void *data)
  * Find all the stuff for git_config_set() below.
  */
 
-#define MAX_MATCHES 512
-
 static struct {
 	int baselen;
 	char *key;
 	int do_not_match;
 	regex_t *value_regex;
 	int multi_replace;
-	size_t offset[MAX_MATCHES];
+	size_t *offset;
+	unsigned int offset_alloc;
 	enum { START, SECTION_SEEN, SECTION_END_SEEN, KEY_SEEN } state;
 	int seen;
 } store;
@@ -1191,11 +1190,11 @@ static int store_aux(const char *key, const char *value, void *cb)
 		if (matches(key, value)) {
 			if (store.seen == 1 && store.multi_replace == 0) {
 				warning("%s has multiple values", key);
-			} else if (store.seen >= MAX_MATCHES) {
-				error("too many matches for %s", key);
-				return 1;
 			}
 
+			ALLOC_GROW(store.offset, store.seen + 1,
+				   store.offset_alloc);
+
 			store.offset[store.seen] = cf->do_ftell(cf);
 			store.seen++;
 		}
@@ -1223,11 +1222,15 @@ static int store_aux(const char *key, const char *value, void *cb)
 		 * Do not increment matches: this is no match, but we
 		 * just made sure we are in the desired section.
 		 */
+		ALLOC_GROW(store.offset, store.seen + 1,
+			   store.offset_alloc);
 		store.offset[store.seen] = cf->do_ftell(cf);
 		/* fallthru */
 	case SECTION_END_SEEN:
 	case START:
 		if (matches(key, value)) {
+			ALLOC_GROW(store.offset, store.seen + 1,
+				   store.offset_alloc);
 			store.offset[store.seen] = cf->do_ftell(cf);
 			store.state = KEY_SEEN;
 			store.seen++;
@@ -1235,6 +1238,9 @@ static int store_aux(const char *key, const char *value, void *cb)
 			if (strrchr(key, '.') - key == store.baselen &&
 			      !strncmp(key, store.key, store.baselen)) {
 					store.state = SECTION_SEEN;
+					ALLOC_GROW(store.offset,
+						   store.seen + 1,
+						   store.offset_alloc);
 					store.offset[store.seen] = cf->do_ftell(cf);
 			}
 		}
@@ -1533,6 +1539,7 @@ int git_config_set_multivar_in_file(const char *config_filename,
 			}
 		}
 
+		ALLOC_GROW(store.offset, 1, store.offset_alloc);
 		store.offset[0] = 0;
 		store.state = START;
 		store.seen = 0;