Add config level support in the config API

Added `struct git_config_entry`: a git_config_entry contains the key, the value, and the config file level from which a config element was found.
Added `git_config_open_level`: build a single-level focused config object from a multi-level one.

We are now storing `git_config_entry`s in the khash of the config_file

7 files changed, 397 insertions, 237 deletions

diff --git a/src/config.c b/src/config.c
index b89c16b1c..f9bd205af 100644
--- a/src/config.c
+++ b/src/config.c
@@ -17,21 +17,29 @@
 #include <ctype.h>
 
 typedef struct {
+	git_refcount rc;
+
 	git_config_file *file;
-	int priority;
+	unsigned int level;
 } file_internal;
 
+static void file_internal_free(file_internal *internal)
+{
+	git_config_file *file;
+
+	file = internal->file;
+	file->free(file);
+	git__free(internal);
+}
+
 static void config_free(git_config *cfg)
 {
 	unsigned int i;
-	git_config_file *file;
 	file_internal *internal;
 
 	for(i = 0; i < cfg->files.length; ++i){
 		internal = git_vector_get(&cfg->files, i);
-		file = internal->file;
-		file->free(file);
-		git__free(internal);
+		GIT_REFCOUNT_DEC(internal, file_internal_free);
 	}
 
 	git_vector_free(&cfg->files);
@@ -51,7 +59,7 @@ static int config_backend_cmp(const void *a, const void *b)
 	const file_internal *bk_a = (const file_internal *)(a);
 	const file_internal *bk_b = (const file_internal *)(b);
 
-	return bk_b->priority - bk_a->priority;
+	return bk_b->level - bk_a->level;
 }
 
 int git_config_new(git_config **out)
@@ -73,20 +81,25 @@ int git_config_new(git_config **out)
 	return 0;
 }
 
-int git_config_add_file_ondisk(git_config *cfg, const char *path, int priority)
+int git_config_add_file_ondisk(
+	git_config *cfg,
+	const char *path,
+	unsigned int level,
+	int force)
 {
 	git_config_file *file = NULL;
+	int res;
 
 	if (git_config_file__ondisk(&file, path) < 0)
 		return -1;
 
-	if (git_config_add_file(cfg, file, priority) < 0) {
+	if ((res = git_config_add_file(cfg, file, level, force)) < 0) {
 		/*
 		 * free manually; the file is not owned by the config
 		 * instance yet and will not be freed on cleanup
 		 */
 		file->free(file);
-		return -1;
+		return res;
 	}
 
 	return 0;
@@ -97,7 +110,7 @@ int git_config_open_ondisk(git_config **cfg, const char *path)
 	if (git_config_new(cfg) < 0)
 		return -1;
 
-	if (git_config_add_file_ondisk(*cfg, path, 1) < 0) {
+	if (git_config_add_file_ondisk(*cfg, path, GIT_CONFIG_LEVEL_LOCAL, 0) < 0) {
 		git_config_free(*cfg);
 		return -1;
 	}
@@ -105,30 +118,152 @@ int git_config_open_ondisk(git_config **cfg, const char *path)
 	return 0;
 }
 
-int git_config_add_file(git_config *cfg, git_config_file *file, int priority)
+static int find_internal_file_by_level(
+	file_internal **internal_out,
+	git_config *cfg,
+	int level)
+{
+	int pos = -1;
+	file_internal *internal;
+	unsigned int i;
+
+	assert(cfg->files.length);
+
+	/* when passing GIT_CONFIG_HIGHEST_LEVEL, the idea is to get the config file
+	 * which has the highest level. As config files are stored in a vector
+	 * sorted by decreasing order of level, getting the file at position 0
+	 * will do the job.
+	 */
+	if (level == GIT_CONFIG_HIGHEST_LEVEL) {
+		pos = 0;
+	} else {
+		git_vector_foreach(&cfg->files, i, internal) {
+			if (internal->level == (unsigned int)level)
+				pos = i;
+		}
+	}
+
+	if (pos == -1) {
+		giterr_set(GITERR_CONFIG,
+			"No config file exists for the given level '%i'", level);
+		return GIT_ENOTFOUND;
+	}
+
+	*internal_out = git_vector_get(&cfg->files, pos);
+
+	return 0;
+}
+
+static int duplicate_level(void **old_raw, void *new_raw)
+{
+	file_internal **old = (file_internal **)old_raw;
+
+	GIT_UNUSED(new_raw);
+
+	giterr_set(GITERR_CONFIG, "A file with the same level (%i) has already been added to the config", (*old)->level);
+	return GIT_EEXISTS;
+}
+
+static void try_remove_existing_file_internal(
+	git_config *cfg,
+	unsigned int level)
+{
+	int pos = -1;
+	file_internal *internal;
+	unsigned int i;
+
+	git_vector_foreach(&cfg->files, i, internal) {
+		if (internal->level == level)
+			pos = i;
+	}
+
+	if (pos == -1)
+		return;
+
+	internal = git_vector_get(&cfg->files, pos);
+
+	if (git_vector_remove(&cfg->files, pos) < 0)
+		return;
+
+	GIT_REFCOUNT_DEC(internal, file_internal_free);
+}
+
+static int git_config__add_internal(
+	git_config *cfg,
+	file_internal *internal,
+	unsigned int level,
+	int force)
+{
+	int result;
+
+	/* delete existing config file for level if it exists */
+	if (force)
+		try_remove_existing_file_internal(cfg, level);
+
+	if ((result = git_vector_insert_sorted(&cfg->files,
+			internal, &duplicate_level)) < 0)
+		return result;
+
+	git_vector_sort(&cfg->files);
+	internal->file->cfg = cfg;
+
+	GIT_REFCOUNT_INC(internal);
+
+	return 0;
+}
+
+int git_config_open_level(
+    git_config **cfg_out,
+    git_config *cfg_parent,
+    unsigned int level)
+{
+	git_config *cfg;
+	file_internal *internal;
+	int res;
+
+	if ((res = find_internal_file_by_level(&internal, cfg_parent, level)) < 0)
+		return res;
+
+	if ((res = git_config_new(&cfg)) < 0)
+		return res;
+
+	if ((res = git_config__add_internal(cfg, internal, level, true)) < 0) {
+		git_config_free(cfg);
+		return res;
+	}
+
+	*cfg_out = cfg;
+
+	return 0;
+}
+
+int git_config_add_file(
+	git_config *cfg,
+	git_config_file *file,
+	unsigned int level,
+	int force)
 {
 	file_internal *internal;
 	int result;
 
 	assert(cfg && file);
 
-	if ((result = file->open(file)) < 0)
+	if ((result = file->open(file, level)) < 0)
 		return result;
 
 	internal = git__malloc(sizeof(file_internal));
 	GITERR_CHECK_ALLOC(internal);
 
+	memset(internal, 0x0, sizeof(file_internal));
+
 	internal->file = file;
-	internal->priority = priority;
+	internal->level = level;
 
-	if (git_vector_insert(&cfg->files, internal) < 0) {
+	if ((result = git_config__add_internal(cfg, internal, level, force)) < 0) {
 		git__free(internal);
-		return -1;
+		return result;
 	}
 
-	git_vector_sort(&cfg->files);
-	internal->file->cfg = cfg;
-
 	return 0;
 }
 
@@ -137,7 +272,7 @@ int git_config_add_file(git_config *cfg, git_config_file *file, int priority)
  */
 
 int git_config_foreach(
-	git_config *cfg, int (*fn)(const char *, const char *, void *), void *data)
+	git_config *cfg, int (*fn)(const git_config_entry *, void *), void *data)
 {
 	return git_config_foreach_match(cfg, NULL, fn, data);
 }
@@ -145,7 +280,7 @@ int git_config_foreach(
 int git_config_foreach_match(
 	git_config *cfg,
 	const char *regexp,
-	int (*fn)(const char *, const char *, void *),
+	int (*fn)(const git_config_entry *, void *),
 	void *data)
 {
 	int ret = 0;
@@ -164,10 +299,8 @@ int git_config_foreach_match(
 
 int git_config_delete(git_config *cfg, const char *name)
 {
-	file_internal *internal;
 	git_config_file *file;
-
-	assert(cfg->files.length);
+	file_internal *internal;
 
 	internal = git_vector_get(&cfg->files, 0);
 	file = internal->file;
@@ -198,10 +331,8 @@ int git_config_set_bool(git_config *cfg, const char *name, int value)
 
 int git_config_set_string(git_config *cfg, const char *name, const char *value)
 {
-	file_internal *internal;
 	git_config_file *file;
-
-	assert(cfg->files.length);
+	file_internal *internal;
 
 	internal = git_vector_get(&cfg->files, 0);
 	file = internal->file;
@@ -209,105 +340,9 @@ int git_config_set_string(git_config *cfg, const char *name, const char *value)
 	return file->set(file, name, value);
 }
 
-static int parse_int64(int64_t *out, const char *value)
-{
-	const char *num_end;
-	int64_t num;
-
-	if (git__strtol64(&num, value, &num_end, 0) < 0)
-		return -1;
-
-	switch (*num_end) {
-	case 'g':
-	case 'G':
-		num *= 1024;
-		/* fallthrough */
-
-	case 'm':
-	case 'M':
-		num *= 1024;
-		/* fallthrough */
-
-	case 'k':
-	case 'K':
-		num *= 1024;
-
-		/* check that that there are no more characters after the
-		 * given modifier suffix */
-		if (num_end[1] != '\0')
-			return -1;
-
-		/* fallthrough */
-
-	case '\0':
-		*out = num;
-		return 0;
-
-	default:
-		return -1;
-	}
-}
-
-static int parse_int32(int32_t *out, const char *value)
-{
-	int64_t tmp;
-	int32_t truncate;
-
-	if (parse_int64(&tmp, value) < 0)
-		return -1;
-
-	truncate = tmp & 0xFFFFFFFF;
-	if (truncate != tmp)
-		return -1;
-
-	*out = truncate;
-	return 0;
-}
-
 /***********
  * Getters
  ***********/
-int git_config_lookup_map_value(
-	git_cvar_map *maps, size_t map_n, const char *value, int *out)
-{
-	size_t i;
-
-	if (!value)
-		return GIT_ENOTFOUND;
-
-	for (i = 0; i < map_n; ++i) {
-		git_cvar_map *m = maps + i;
-
-		switch (m->cvar_type) {
-		case GIT_CVAR_FALSE:
-		case GIT_CVAR_TRUE: {
-			int bool_val;
-
-			if (git__parse_bool(&bool_val, value) == 0 &&
-				bool_val == (int)m->cvar_type) {
-				*out = m->map_value;
-				return 0;
-			}
-			break;
-		}
-
-		case GIT_CVAR_INT32:
-			if (parse_int32(out, value) == 0)
-				return 0;
-			break;
-
-		case GIT_CVAR_STRING:
-			if (strcasecmp(value, m->str_match) == 0) {
-				*out = m->map_value;
-				return 0;
-			}
-			break;
-		}
-	}
-
-	return GIT_ENOTFOUND;
-}
-
 int git_config_get_mapped(
 	int *out,
 	git_config *cfg,
@@ -318,16 +353,10 @@ int git_config_get_mapped(
 	const char *value;
 	int ret;
 
-	ret = git_config_get_string(&value, cfg, name);
-	if (ret < 0)
+	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
 		return ret;
 
-	if (!git_config_lookup_map_value(maps, map_n, value, out))
-		return 0;
-
-	giterr_set(GITERR_CONFIG,
-		"Failed to map the '%s' config variable with a valid value", name);
-	return -1;
+	return git_config_lookup_map_value(out, maps, map_n, value);
 }
 
 int git_config_get_int64(int64_t *out, git_config *cfg, const char *name)
@@ -335,16 +364,10 @@ int git_config_get_int64(int64_t *out, git_config *cfg, const char *name)
 	const char *value;
 	int ret;
 
-	ret = git_config_get_string(&value, cfg, name);
-	if (ret < 0)
+	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
 		return ret;
 
-	if (parse_int64(out, value) < 0) {
-		giterr_set(GITERR_CONFIG, "Failed to parse '%s' as an integer", value);
-		return -1;
-	}
-
-	return 0;
+	return git_config_parse_int64(out, value);
 }
 
 int git_config_get_int32(int32_t *out, git_config *cfg, const char *name)
@@ -352,16 +375,10 @@ int git_config_get_int32(int32_t *out, git_config *cfg, const char *name)
 	const char *value;
 	int ret;
 
-	ret = git_config_get_string(&value, cfg, name);
-	if (ret < 0)
+	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
 		return ret;
 
-	if (parse_int32(out, value) < 0) {
-		giterr_set(GITERR_CONFIG, "Failed to parse '%s' as a 32-bit integer", value);
-		return -1;
-	}
-
-	return 0;
+	return git_config_parse_int32(out, value);
 }
 
 int git_config_get_bool(int *out, git_config *cfg, const char *name)
@@ -369,20 +386,24 @@ int git_config_get_bool(int *out, git_config *cfg, const char *name)
 	const char *value;
 	int ret;
 
-	ret = git_config_get_string(&value, cfg, name);
-	if (ret < 0)
+	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
 		return ret;
 
-	if (git__parse_bool(out, value) == 0)
-		return 0;
+	return git_config_parse_bool(out, value);
+}
 
-	if (parse_int32(out, value) == 0) {
-		*out = !!(*out);
-		return 0;
-	}
+static int get_string_at_file(const char **out, git_config_file *file, const char *name)
+{
+	const git_config_entry *entry;
+	int res;
 
-	giterr_set(GITERR_CONFIG, "Failed to parse '%s' as a boolean value", value);
-	return -1;
+	*out = NULL;
+
+	res = file->get(file, name, &entry);
+	if (res != GIT_ENOTFOUND)
+		*out = entry->value;
+
+	return res;
 }
 
 int git_config_get_string(const char **out, git_config *cfg, const char *name)
@@ -392,6 +413,23 @@ int git_config_get_string(const char **out, git_config *cfg, const char *name)
 
 	assert(cfg->files.length);
 
+	git_vector_foreach(&cfg->files, i, internal) {
+		int res = get_string_at_file(out, internal->file, name);
+
+		if (res != GIT_ENOTFOUND)
+			return res;
+	}
+
+	return GIT_ENOTFOUND;
+}
+
+int git_config_get_config_entry(const git_config_entry **out, git_config *cfg, const char *name)
+{
+	file_internal *internal;
+	unsigned int i;
+
+	assert(cfg->files.length);
+
 	*out = NULL;
 
 	git_vector_foreach(&cfg->files, i, internal) {
@@ -405,7 +443,7 @@ int git_config_get_string(const char **out, git_config *cfg, const char *name)
 }
 
 int git_config_get_multivar(git_config *cfg, const char *name, const char *regexp,
-			    int (*fn)(const char *value, void *data), void *data)
+			    int (*fn)(const git_config_entry *entry, void *data), void *data)
 {
 	file_internal *internal;
 	git_config_file *file;
@@ -431,20 +469,13 @@ int git_config_get_multivar(git_config *cfg, const char *name, const char *regex
 
 int git_config_set_multivar(git_config *cfg, const char *name, const char *regexp, const char *value)
 {
-	file_internal *internal;
 	git_config_file *file;
-	int ret = GIT_ENOTFOUND;
-	size_t i;
+	file_internal *internal;
 
-	for (i = cfg->files.length; i > 0; --i) {
-		internal = git_vector_get(&cfg->files, i - 1);
-		file = internal->file;
-		ret = file->set_multivar(file, name, regexp, value);
-		if (ret < 0 && ret != GIT_ENOTFOUND)
-			return ret;
-	}
+	internal = git_vector_get(&cfg->files, 0);
+	file = internal->file;
 
-	return 0;
+	return file->set_multivar(file, name, regexp, value);
 }
 
 int git_config_find_global_r(git_buf *path)
@@ -541,13 +572,16 @@ int git_config_open_default(git_config **out)
 	error = git_config_new(&cfg);
 
 	if (!error && !git_config_find_global_r(&buf))
-		error = git_config_add_file_ondisk(cfg, buf.ptr, 3);
+		error = git_config_add_file_ondisk(cfg, buf.ptr,
+			GIT_CONFIG_LEVEL_GLOBAL, 0);
 
 	if (!error && !git_config_find_xdg_r(&buf))
-		error = git_config_add_file_ondisk(cfg, buf.ptr, 2);
+		error = git_config_add_file_ondisk(cfg, buf.ptr,
+			GIT_CONFIG_LEVEL_XDG, 0);
 
 	if (!error && !git_config_find_system_r(&buf))
-		error = git_config_add_file_ondisk(cfg, buf.ptr, 1);
+		error = git_config_add_file_ondisk(cfg, buf.ptr,
+			GIT_CONFIG_LEVEL_SYSTEM, 0);
 
 	git_buf_free(&buf);
 
@@ -560,3 +594,129 @@ int git_config_open_default(git_config **out)
 
 	return error;
 }
+
+/***********
+ * Parsers
+ ***********/
+int git_config_lookup_map_value(
+	int *out,
+	git_cvar_map *maps,
+	size_t map_n,
+	const char *value)
+{
+	size_t i;
+
+	if (!value)
+		goto fail_parse;
+
+	for (i = 0; i < map_n; ++i) {
+		git_cvar_map *m = maps + i;
+
+		switch (m->cvar_type) {
+		case GIT_CVAR_FALSE:
+		case GIT_CVAR_TRUE: {
+			int bool_val;
+
+			if (git__parse_bool(&bool_val, value) == 0 &&
+				bool_val == (int)m->cvar_type) {
+				*out = m->map_value;
+				return 0;
+			}
+			break;
+		}
+
+		case GIT_CVAR_INT32:
+			if (git_config_parse_int32(out, value) == 0)
+				return 0;
+			break;
+
+		case GIT_CVAR_STRING:
+			if (strcasecmp(value, m->str_match) == 0) {
+				*out = m->map_value;
+				return 0;
+			}
+			break;
+		}
+	}
+
+fail_parse:
+	giterr_set(GITERR_CONFIG, "Failed to map '%s'", value);
+	return -1;
+}
+
+int git_config_parse_bool(int *out, const char *value)
+{
+	if (git__parse_bool(out, value) == 0)
+		return 0;
+
+	if (git_config_parse_int32(out, value) == 0) {
+		*out = !!(*out);
+		return 0;
+	}
+
+	giterr_set(GITERR_CONFIG, "Failed to parse '%s' as a boolean value", value);
+	return -1;
+}
+
+int git_config_parse_int64(int64_t *out, const char *value)
+{
+	const char *num_end;
+	int64_t num;
+
+	if (git__strtol64(&num, value, &num_end, 0) < 0)
+		goto fail_parse;
+
+	switch (*num_end) {
+	case 'g':
+	case 'G':
+		num *= 1024;
+		/* fallthrough */
+
+	case 'm':
+	case 'M':
+		num *= 1024;
+		/* fallthrough */
+
+	case 'k':
+	case 'K':
+		num *= 1024;
+
+		/* check that that there are no more characters after the
+		 * given modifier suffix */
+		if (num_end[1] != '\0')
+			return -1;
+
+		/* fallthrough */
+
+	case '\0':
+		*out = num;
+		return 0;
+
+	default:
+		goto fail_parse;
+	}
+
+fail_parse:
+	giterr_set(GITERR_CONFIG, "Failed to parse '%s' as an integer", value);
+	return -1;
+}
+
+int git_config_parse_int32(int32_t *out, const char *value)
+{
+	int64_t tmp;
+	int32_t truncate;
+
+	if (git_config_parse_int64(&tmp, value) < 0)
+		goto fail_parse;
+
+	truncate = tmp & 0xFFFFFFFF;
+	if (truncate != tmp)
+		goto fail_parse;
+
+	*out = truncate;
+	return 0;
+
+fail_parse:
+	giterr_set(GITERR_CONFIG, "Failed to parse '%s' as a 32-bit integer", value);
+	return -1;
+}
diff --git a/src/config.h b/src/config.h
index 471b42dad..16b8413b7 100644
--- a/src/config.h
+++ b/src/config.h
@@ -27,9 +27,4 @@ extern int git_config_find_global_r(git_buf *global_config_path);
 extern int git_config_find_xdg_r(git_buf *system_config_path);
 extern int git_config_find_system_r(git_buf *system_config_path);
 
-extern int git_config_parse_bool(int *out, const char *bool_string);
-
-extern int git_config_lookup_map_value(
-	git_cvar_map *maps, size_t map_n, const char *value, int *out);
-
 #endif
diff --git a/src/config_file.c b/src/config_file.c
index 12ae4a214..92fe13296 100644
--- a/src/config_file.c
+++ b/src/config_file.c
@@ -22,15 +22,9 @@ GIT__USE_STRMAP;
 
 typedef struct cvar_t {
 	struct cvar_t *next;
-	char *key; /* TODO: we might be able to get rid of this */
-	char *value;
+	git_config_entry *entry;
 } cvar_t;
 
-typedef struct {
-	struct cvar_t *head;
-	struct cvar_t *tail;
-} cvar_t_list;
-
 #define CVAR_LIST_HEAD(list) ((list)->head)
 
 #define CVAR_LIST_TAIL(list) ((list)->tail)
@@ -84,7 +78,7 @@ typedef struct {
 	char *file_path;
 } diskfile_backend;
 
-static int config_parse(diskfile_backend *cfg_file);
+static int config_parse(diskfile_backend *cfg_file, unsigned int level);
 static int parse_variable(diskfile_backend *cfg, char **var_name, char **var_value);
 static int config_write(diskfile_backend *cfg, const char *key, const regex_t *preg, const char *value);
 static char *escape_value(const char *ptr);
@@ -100,8 +94,9 @@ static void cvar_free(cvar_t *var)
 	if (var == NULL)
 		return;
 
-	git__free(var->key);
-	git__free(var->value);
+	git__free((char*)var->entry->name);
+	git__free((char *)var->entry->value);
+	git__free(var->entry);
 	git__free(var);
 }
 
@@ -150,7 +145,7 @@ static void free_vars(git_strmap *values)
 	git_strmap_free(values);
 }
 
-static int config_open(git_config_file *cfg)
+static int config_open(git_config_file *cfg, unsigned int level)
 {
 	int res;
 	diskfile_backend *b = (diskfile_backend *)cfg;
@@ -165,7 +160,7 @@ static int config_open(git_config_file *cfg)
 	if (res == GIT_ENOTFOUND)
 		return 0;
 
-	if (res < 0 || config_parse(b) <  0) {
+	if (res < 0 || config_parse(b, level) <  0) {
 		free_vars(b->values);
 		b->values = NULL;
 		git_buf_free(&b->reader.buffer);
@@ -191,7 +186,7 @@ static void backend_free(git_config_file *_backend)
 static int file_foreach(
 	git_config_file *backend,
 	const char *regexp,
-	int (*fn)(const char *, const char *, void *),
+	int (*fn)(const git_config_entry *, void *),
 	void *data)
 {
 	diskfile_backend *b = (diskfile_backend *)backend;
@@ -220,7 +215,7 @@ static int file_foreach(
 				continue;
 
 			/* abort iterator on non-zero return value */
-			if (fn(key, var->value, data)) {
+			if (fn(var->entry, data)) {
 				giterr_clear();
 				result = GIT_EUSER;
 				goto cleanup;
@@ -263,8 +258,8 @@ static int config_set(git_config_file *cfg, const char *name, const char *value)
 		}
 
 		/* don't update if old and new values already match */
-		if ((!existing->value && !value) ||
-			(existing->value && value && !strcmp(existing->value, value)))
+		if ((!existing->entry->value && !value) ||
+			(existing->entry->value && value && !strcmp(existing->entry->value, value)))
 			return 0;
 
 		if (value) {
@@ -274,10 +269,10 @@ static int config_set(git_config_file *cfg, const char *name, const char *value)
 			GITERR_CHECK_ALLOC(esc_value);
 		}
 
-		git__free(existing->value);
-		existing->value = tmp;
+		git__free((void *)existing->entry->value);
+		existing->entry->value = tmp;
 
-		ret = config_write(b, existing->key, NULL, esc_value);
+		ret = config_write(b, existing->entry->name, NULL, esc_value);
 
 		git__free(esc_value);
 		return ret;
@@ -285,15 +280,17 @@ static int config_set(git_config_file *cfg, const char *name, const char *value)
 
 	var = git__malloc(sizeof(cvar_t));
 	GITERR_CHECK_ALLOC(var);
-
 	memset(var, 0x0, sizeof(cvar_t));
+	var->entry = git__malloc(sizeof(git_config_entry));
+	GITERR_CHECK_ALLOC(var->entry);
+	memset(var->entry, 0x0, sizeof(git_config_entry));
 
-	var->key = key;
-	var->value = NULL;
+	var->entry->name = key;
+	var->entry->value = NULL;
 
 	if (value) {
-		var->value = git__strdup(value);
-		GITERR_CHECK_ALLOC(var->value);
+		var->entry->value = git__strdup(value);
+		GITERR_CHECK_ALLOC(var->entry->value);
 		esc_value = escape_value(value);
 		GITERR_CHECK_ALLOC(esc_value);
 	}
@@ -317,7 +314,7 @@ static int config_set(git_config_file *cfg, const char *name, const char *value)
 /*
  * Internal function that actually gets the value in string form
  */
-static int config_get(git_config_file *cfg, const char *name, const char **out)
+static int config_get(git_config_file *cfg, const char *name, const git_config_entry **out)
 {
 	diskfile_backend *b = (diskfile_backend *)cfg;
 	char *key;
@@ -333,7 +330,7 @@ static int config_get(git_config_file *cfg, const char *name, const char **out)
 	if (!git_strmap_valid_index(b->values, pos))
 		return GIT_ENOTFOUND;
 
-	*out = ((cvar_t *)git_strmap_value_at(b->values, pos))->value;
+	*out = ((cvar_t *)git_strmap_value_at(b->values, pos))->entry;
 
 	return 0;
 }
@@ -342,7 +339,7 @@ static int config_get_multivar(
 	git_config_file *cfg,
 	const char *name,
 	const char *regex_str,
-	int (*fn)(const char *, void *),
+	int (*fn)(const git_config_entry *, void *),
 	void *data)
 {
 	cvar_t *var;
@@ -376,10 +373,10 @@ static int config_get_multivar(
 		/* and throw the callback only on the variables that
 		 * match the regex */
 		do {
-			if (regexec(&regex, var->value, 0, NULL, 0) == 0) {
+			if (regexec(&regex, var->entry->value, 0, NULL, 0) == 0) {
 				/* early termination by the user is not an error;
 				 * just break and return successfully */
-				if (fn(var->value, data) < 0)
+				if (fn(var->entry, data) < 0)
 					break;
 			}
 
@@ -391,7 +388,7 @@ static int config_get_multivar(
 		do {
 			/* early termination by the user is not an error;
 			 * just break and return successfully */
-			if (fn(var->value, data) < 0)
+			if (fn(var->entry, data) < 0)
 				break;
 
 			var = var->next;
@@ -434,12 +431,12 @@ static int config_set_multivar(
 	}
 
 	for (;;) {
-		if (regexec(&preg, var->value, 0, NULL, 0) == 0) {
+		if (regexec(&preg, var->entry->value, 0, NULL, 0) == 0) {
 			char *tmp = git__strdup(value);
 			GITERR_CHECK_ALLOC(tmp);
 
-			git__free(var->value);
-			var->value = tmp;
+			git__free((void *)var->entry->value);
+			var->entry->value = tmp;
 			replaced = 1;
 		}
 
@@ -453,14 +450,18 @@ static int config_set_multivar(
 	if (!replaced) {
 		newvar = git__malloc(sizeof(cvar_t));
 		GITERR_CHECK_ALLOC(newvar);
-
 		memset(newvar, 0x0, sizeof(cvar_t));
+		newvar->entry = git__malloc(sizeof(git_config_entry));
+		GITERR_CHECK_ALLOC(newvar->entry);
+		memset(newvar->entry, 0x0, sizeof(git_config_entry));
+
+		newvar->entry->name = git__strdup(var->entry->name);
+		GITERR_CHECK_ALLOC(newvar->entry->name);
 
-		newvar->key = git__strdup(var->key);
-		GITERR_CHECK_ALLOC(newvar->key);
+		newvar->entry->value = git__strdup(value);
+		GITERR_CHECK_ALLOC(newvar->entry->value);
 
-		newvar->value = git__strdup(value);
-		GITERR_CHECK_ALLOC(newvar->value);
+		newvar->entry->level = var->entry->level;
 
 		var->next = newvar;
 	}
@@ -501,7 +502,7 @@ static int config_delete(git_config_file *cfg, const char *name)
 
 	git_strmap_delete_at(b->values, pos);
 
-	result = config_write(b, var->key, NULL, NULL);
+	result = config_write(b, var->entry->name, NULL, NULL);
 
 	cvar_free(var);
 	return result;
@@ -898,7 +899,7 @@ static int strip_comments(char *line, int in_quotes)
 	return quote_count;
 }
 
-static int config_parse(diskfile_backend *cfg_file)
+static int config_parse(diskfile_backend *cfg_file, unsigned int level)
 {
 	int c;
 	char *current_section = NULL;
@@ -946,8 +947,10 @@ static int config_parse(diskfile_backend *cfg_file)
 
 			var = git__malloc(sizeof(cvar_t));
 			GITERR_CHECK_ALLOC(var);
-
 			memset(var, 0x0, sizeof(cvar_t));
+			var->entry = git__malloc(sizeof(git_config_entry));
+			GITERR_CHECK_ALLOC(var->entry);
+			memset(var->entry, 0x0, sizeof(git_config_entry));
 
 			git__strtolower(var_name);
 			git_buf_printf(&buf, "%s.%s", current_section, var_name);
@@ -956,13 +959,14 @@ static int config_parse(diskfile_backend *cfg_file)
 			if (git_buf_oom(&buf))
 				return -1;
 
-			var->key = git_buf_detach(&buf);
-			var->value = var_value;
+			var->entry->name = git_buf_detach(&buf);
+			var->entry->value = var_value;
+			var->entry->level = level;
 
 			/* Add or append the new config option */
-			pos = git_strmap_lookup_index(cfg_file->values, var->key);
+			pos = git_strmap_lookup_index(cfg_file->values, var->entry->name);
 			if (!git_strmap_valid_index(cfg_file->values, pos)) {
-				git_strmap_insert(cfg_file->values, var->key, var, result);
+				git_strmap_insert(cfg_file->values, var->entry->name, var, result);
 				if (result < 0)
 					break;
 				result = 0;
diff --git a/src/config_file.h b/src/config_file.h
index bf687b516..b500dd64f 100644
--- a/src/config_file.h
+++ b/src/config_file.h
@@ -9,9 +9,9 @@
 
 #include "git2/config.h"
 
-GIT_INLINE(int) git_config_file_open(git_config_file *cfg)
+GIT_INLINE(int) git_config_file_open(git_config_file *cfg, unsigned int level)
 {
-	return cfg->open(cfg);
+	return cfg->open(cfg, level);
 }
 
 GIT_INLINE(void) git_config_file_free(git_config_file *cfg)
@@ -20,7 +20,7 @@ GIT_INLINE(void) git_config_file_free(git_config_file *cfg)
 }
 
 GIT_INLINE(int) git_config_file_get_string(
-	const char **out, git_config_file *cfg, const char *name)
+	const git_config_entry **out, git_config_file *cfg, const char *name)
 {
 	return cfg->get(cfg, name, out);
 }
@@ -39,7 +39,7 @@ GIT_INLINE(int) git_config_file_delete(
 
 GIT_INLINE(int) git_config_file_foreach(
 	git_config_file *cfg,
-	int (*fn)(const char *key, const char *value, void *data),
+	int (*fn)(const git_config_entry *entry, void *data),
 	void *data)
 {
 	return cfg->foreach(cfg, NULL, fn, data);
@@ -48,7 +48,7 @@ GIT_INLINE(int) git_config_file_foreach(
 GIT_INLINE(int) git_config_file_foreach_match(
 	git_config_file *cfg,
 	const char *regexp,
-	int (*fn)(const char *key, const char *value, void *data),
+	int (*fn)(const git_config_entry *entry, void *data),
 	void *data)
 {
 	return cfg->foreach(cfg, regexp, fn, data);
diff --git a/src/remote.c b/src/remote.c
index 5ef791d39..e05ea059f 100644
--- a/src/remote.c
+++ b/src/remote.c
@@ -637,12 +637,12 @@ struct cb_data {
 	regex_t *preg;
 };
 
-static int remote_list_cb(const char *name, const char *value, void *data_)
+static int remote_list_cb(const git_config_entry *entry, void *data_)
 {
 	struct cb_data *data = (struct cb_data *)data_;
 	size_t nmatch = 2;
 	regmatch_t pmatch[2];
-	GIT_UNUSED(value);
+	const char *name = entry->name;
 
 	if (!regexec(data->preg, name, nmatch, pmatch, 0)) {
 		char *remote_name = git__strndup(&name[pmatch[1].rm_so], pmatch[1].rm_eo - pmatch[1].rm_so);
diff --git a/src/repository.c b/src/repository.c
index db0888a89..43e0eda8f 100644
--- a/src/repository.c
+++ b/src/repository.c
@@ -461,23 +461,23 @@ static int load_config(
 		&config_path, repo->path_repository, GIT_CONFIG_FILENAME_INREPO) < 0)
 		goto on_error;
 
-	if (git_config_add_file_ondisk(cfg, config_path.ptr, 4) < 0)
+	if (git_config_add_file_ondisk(cfg, config_path.ptr, GIT_CONFIG_LEVEL_LOCAL, 0) < 0)
 		goto on_error;
 
 	git_buf_free(&config_path);
 
 	if (global_config_path != NULL) {
-		if (git_config_add_file_ondisk(cfg, global_config_path, 3) < 0)
+		if (git_config_add_file_ondisk(cfg, global_config_path, GIT_CONFIG_LEVEL_GLOBAL, 0) < 0)
 			goto on_error;
 	}
 
 	if (xdg_config_path != NULL) {
-		if (git_config_add_file_ondisk(cfg, xdg_config_path, 2) < 0)
+		if (git_config_add_file_ondisk(cfg, xdg_config_path, GIT_CONFIG_LEVEL_XDG, 0) < 0)
 			goto on_error;
 	}
 
 	if (system_config_path != NULL) {
-		if (git_config_add_file_ondisk(cfg, system_config_path, 1) < 0)
+		if (git_config_add_file_ondisk(cfg, system_config_path, GIT_CONFIG_LEVEL_SYSTEM, 0) < 0)
 			goto on_error;
 	}
 
diff --git a/src/submodule.c b/src/submodule.c
index 180528641..e3657f9ad 100644
--- a/src/submodule.c
+++ b/src/submodule.c
@@ -72,7 +72,7 @@ static int submodule_get(git_submodule **, git_repository *, const char *, const
 static void submodule_release(git_submodule *sm, int decr);
 static int submodule_load_from_index(git_repository *, const git_index_entry *);
 static int submodule_load_from_head(git_repository*, const char*, const git_oid*);
-static int submodule_load_from_config(const char *, const char *, void *);
+static int submodule_load_from_config(const git_config_entry *, void *);
 static int submodule_load_from_wd_lite(git_submodule *, const char *, void *);
 static int submodule_update_config(git_submodule *, const char *, const char *, bool, bool);
 static void submodule_mode_mismatch(git_repository *, const char *, unsigned int);
@@ -974,11 +974,12 @@ static int submodule_config_error(const char *property, const char *value)
 }
 
 static int submodule_load_from_config(
-	const char *key, const char *value, void *data)
+	const git_config_entry *entry, void *data)
 {
 	git_repository *repo = data;
 	git_strmap *smcfg = repo->submodules;
 	const char *namestart, *property, *alternate = NULL;
+	const char *key = entry->name, *value = entry->value;
 	git_buf name = GIT_BUF_INIT;
 	git_submodule *sm;
 	bool is_path;
@@ -1055,7 +1056,7 @@ static int submodule_load_from_config(
 	else if (strcasecmp(property, "update") == 0) {
 		int val;
 		if (git_config_lookup_map_value(
-			_sm_update_map, ARRAY_SIZE(_sm_update_map), value, &val) < 0)
+			&val, _sm_update_map, ARRAY_SIZE(_sm_update_map), value) < 0)
 			return submodule_config_error("update", value);
 		sm->update_default = sm->update = (git_submodule_update_t)val;
 	}
@@ -1066,7 +1067,7 @@ static int submodule_load_from_config(
 	else if (strcasecmp(property, "ignore") == 0) {
 		int val;
 		if (git_config_lookup_map_value(
-			_sm_ignore_map, ARRAY_SIZE(_sm_ignore_map), value, &val) < 0)
+			&val, _sm_ignore_map, ARRAY_SIZE(_sm_ignore_map), value) < 0)
 			return submodule_config_error("ignore", value);
 		sm->ignore_default = sm->ignore = (git_submodule_ignore_t)val;
 	}
@@ -1204,7 +1205,7 @@ static git_config_file *open_gitmodules(
 			if (git_config_file__ondisk(&mods, path.ptr) < 0)
 				mods = NULL;
 			/* open should only fail here if the file is malformed */
-			else if (git_config_file_open(mods) < 0) {
+			else if (git_config_file_open(mods, GIT_CONFIG_LEVEL_LOCAL) < 0) {
 				git_config_file_free(mods);
 				mods = NULL;
 			}