Merge branch 'ps/leakfixes' into ps/no-writable-strings

* ps/leakfixes:
  builtin/mv: fix leaks for submodule gitfile paths
  builtin/mv: refactor to use `struct strvec`
  builtin/mv duplicate string list memory
  builtin/mv: refactor `add_slash()` to always return allocated strings
  strvec: add functions to replace and remove strings
  submodule: fix leaking memory for submodule entries
  commit-reach: fix memory leak in `ahead_behind()`
  builtin/credential: clear credential before exit
  config: plug various memory leaks
  config: clarify memory ownership in `git_config_string()`
  builtin/log: stop using globals for format config
  builtin/log: stop using globals for log config
  convert: refactor code to clarify ownership of check_roundtrip_encoding
  diff: refactor code to clarify memory ownership of prefixes
  config: clarify memory ownership in `git_config_pathname()`
  http: refactor code to clarify memory ownership
  checkout: clarify memory ownership in `unique_tracking_name()`
  strbuf: fix leak when `appendwholeline()` fails with EOF
  transport-helper: fix leaking helper name

1 files changed, 11 insertions, 9 deletions

diff --git a/diff.c b/diff.c
index ded9ac70df..e70301df76 100644
--- a/diff.c
+++ b/diff.c
@@ -56,14 +56,14 @@ static int diff_color_moved_default;
 static int diff_color_moved_ws_default;
 static int diff_context_default = 3;
 static int diff_interhunk_context_default;
-static const char *diff_word_regex_cfg;
-static const char *external_diff_cmd_cfg;
-static const char *diff_order_file_cfg;
+static char *diff_word_regex_cfg;
+static char *external_diff_cmd_cfg;
+static char *diff_order_file_cfg;
 int diff_auto_refresh_index = 1;
 static int diff_mnemonic_prefix;
 static int diff_no_prefix;
-static const char *diff_src_prefix = "a/";
-static const char *diff_dst_prefix = "b/";
+static char *diff_src_prefix;
+static char *diff_dst_prefix;
 static int diff_relative;
 static int diff_stat_name_width;
 static int diff_stat_graph_width;
@@ -411,9 +411,11 @@ int git_diff_ui_config(const char *var, const char *value,
 		return 0;
 	}
 	if (!strcmp(var, "diff.srcprefix")) {
+		FREE_AND_NULL(diff_src_prefix);
 		return git_config_string(&diff_src_prefix, var, value);
 	}
 	if (!strcmp(var, "diff.dstprefix")) {
+		FREE_AND_NULL(diff_dst_prefix);
 		return git_config_string(&diff_dst_prefix, var, value);
 	}
 	if (!strcmp(var, "diff.relative")) {
@@ -3433,8 +3435,8 @@ void diff_set_noprefix(struct diff_options *options)
 
 void diff_set_default_prefix(struct diff_options *options)
 {
-	options->a_prefix = diff_src_prefix;
-	options->b_prefix = diff_dst_prefix;
+	options->a_prefix = diff_src_prefix ? diff_src_prefix : "a/";
+	options->b_prefix = diff_dst_prefix ? diff_dst_prefix : "b/";
 }
 
 struct userdiff_driver *get_textconv(struct repository *r,
@@ -5371,8 +5373,8 @@ static int diff_opt_default_prefix(const struct option *opt,
 
 	BUG_ON_OPT_NEG(unset);
 	BUG_ON_OPT_ARG(optarg);
-	diff_src_prefix = "a/";
-	diff_dst_prefix = "b/";
+	FREE_AND_NULL(diff_src_prefix);
+	FREE_AND_NULL(diff_dst_prefix);
 	diff_set_default_prefix(options);
 	return 0;
 }