[PATCH 4/7] add line number and file name info to `config_set`

[Tanay Abhra <tanayabh@gmail.com>]

Store file name and line number for each key-value pair in the cache.
Use the information to print line number and file name in errors raised
by `git_config()` which now uses the configuration files caching layer
internally.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 config.c | 32 ++++++++++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/config.c b/config.c
index a7fb9a4..43a951f 100644
--- a/config.c
+++ b/config.c
@@ -1237,9 +1237,15 @@ static int git_config_raw(config_fn_t fn, void *data)
 	return git_config_with_options(fn, data, NULL, 1);
 }
 
+struct key_value_info {
+	const char *filename;
+	int linenr;
+};
+
 static int configset_iter(struct config_set *cs, config_fn_t fn, void *data)
 {
 	int i;
+	struct key_value_info *kv_info;
 	struct string_list *strptr;
 	struct config_set_element *entry;
 	struct hashmap_iter iter;
@@ -1247,8 +1253,15 @@ static int configset_iter(struct config_set *cs, config_fn_t fn, void *data)
 	while ((entry = hashmap_iter_next(&iter))) {
 		strptr = &entry->value_list;
 		for (i = 0; i < strptr->nr; i++) {
-			if (fn(entry->key, strptr->items[i].string, data) < 0)
-				die("bad config file line in (TODO: file/line info)");
+			if (fn(entry->key, strptr->items[i].string, data) < 0) {
+				kv_info = strptr->items[i].util;
+				if (!kv_info->linenr)
+					die("unable to parse command-line config");
+				else
+					die("bad config file line %d in %s",
+						kv_info->linenr,
+						kv_info->filename);
+			}
 		}
 	}
 	return 0;
@@ -1287,6 +1300,8 @@ static struct config_set_element *configset_find_element(struct config_set *cs,
 static int configset_add_value(struct config_set *cs, const char *key, const char *value)
 {
 	struct config_set_element *e;
+	struct key_value_info *kv_info = xmalloc(sizeof(*kv_info));
+	struct string_list_item *si;
 	e = configset_find_element(cs, key);
 	/*
 	 * Since the keys are being fed by git_config*() callback mechanism, they
@@ -1299,7 +1314,16 @@ static int configset_add_value(struct config_set *cs, const char *key, const cha
 		string_list_init(&e->value_list, 1);
 		hashmap_add(&cs->config_hash, e);
 	}
-	string_list_append_nodup(&e->value_list, value ? xstrdup(value) : NULL);
+	si = string_list_append_nodup(&e->value_list, value ? xstrdup(value) : NULL);
+	if (cf) {
+		kv_info->filename = strintern(cf->name);
+		kv_info->linenr = cf->linenr;
+	} else {
+		/* for values read from `git_config_from_parameters()` */
+		kv_info->filename = strintern("parameter");
+		kv_info->linenr = 0;
+	}
+	si->util = kv_info;
 
 	return 0;
 }
@@ -1326,7 +1350,7 @@ void git_configset_clear(struct config_set *cs)
 	hashmap_iter_init(&cs->config_hash, &iter);
 	while ((entry = hashmap_iter_next(&iter))) {
 		free(entry->key);
-		string_list_clear(&entry->value_list, 0);
+		string_list_clear(&entry->value_list, 1);
 	}
 	hashmap_free(&cs->config_hash, 1);
 	cs->hash_initialized = 0;
-- 
1.9.0.GIT