git_config_parse_key(): return baselen as size_t

As with the recent change to parse_config_key(), the best type to return
a string length is a size_t, as it won't cause integer truncation for a
gigantic key. And as with that change, this is mostly a clarity /
hygiene issue for now, as our config parser would choke on such a large
key anyway.

There are a few ripple effects within the config code, as callers switch
to using size_t. I also adjusted a few related variables that iterate
over strings. The most unexpected change is that a call to strbuf_addf()
had to switch to strbuf_add(). We can't use a size_t with "%.*s",
because printf precisions must have type "int" (we could cast, of
course, but that would miss the point of using size_t in the first
place).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

config.c

@@ -358,12 +358,13 @@ static inline int iskeychar(int c)
  *
  * store_key - pointer to char* which will hold a copy of the key with
  *             lowercase section and variable name
- * baselen - pointer to int which will hold the length of the
+ * baselen - pointer to size_t which will hold the length of the
  *           section + subsection part, can be NULL
  */
-static int git_config_parse_key_1(const char *key, char **store_key, int *baselen_, int quiet)
+static int git_config_parse_key_1(const char *key, char **store_key, size_t *baselen_, int quiet)
 {
-	int i, dot, baselen;
+	size_t i, baselen;
+	int dot;
 	const char *last_dot = strrchr(key, '.');
 
 	/*
@@ -425,7 +426,7 @@ static int git_config_parse_key_1(const char *key, char **store_key, int *basele
 	return -CONFIG_INVALID_KEY;
 }
 
-int git_config_parse_key(const char *key, char **store_key, int *baselen)
+int git_config_parse_key(const char *key, char **store_key, size_t *baselen)
 {
 	return git_config_parse_key_1(key, store_key, baselen, 0);
 }
@@ -2383,7 +2384,7 @@ void git_die_config(const char *key, const char *err, ...)
  */
 
 struct config_store_data {
-	int baselen;
+	size_t baselen;
 	char *key;
 	int do_not_match;
 	regex_t *value_regex;
@@ -2509,7 +2510,7 @@ static struct strbuf store_create_section(const char *key,
 					  const struct config_store_data *store)
 {
 	const char *dot;
-	int i;
+	size_t i;
 	struct strbuf sb = STRBUF_INIT;
 
 	dot = memchr(key, '.', store->baselen);
@@ -2522,7 +2523,9 @@ static struct strbuf store_create_section(const char *key,
 		}
 		strbuf_addstr(&sb, "\"]\n");
 	} else {
-		strbuf_addf(&sb, "[%.*s]\n", store->baselen, key);
+		strbuf_addch(&sb, '[');
+		strbuf_add(&sb, key, store->baselen);
+		strbuf_addstr(&sb, "]\n");
 	}
 
 	return sb;

config.h

@@ -254,7 +254,7 @@ int git_config_set_gently(const char *, const char *);
  */
 void git_config_set(const char *, const char *);
 
-int git_config_parse_key(const char *, char **, int *);
+int git_config_parse_key(const char *, char **, size_t *);
 int git_config_key_is_valid(const char *key);
 int git_config_set_multivar_gently(const char *, const char *, const char *, int);
 void git_config_set_multivar(const char *, const char *, const char *, int);