Re: [PATCH 2/1] config: let `config_store_data_clear()` handle `value_regex`

[Eric Sunshine]

On Sun, May 13, 2018 at 5:58 AM, Martin Ågren  wrote:
> Instead of carefully clearing up `value_regex` in each code path, let
> `config_store_data_clear()` handle that.
>
> Signed-off-by: Martin Ågren 
> ---
> I *think* that it should be ok to `regfree()` after `regcomp()` failed,
> but I'll need to look into that some more (and say something about it in
> the commit message).

My research (for instance [1,2]) seems to indicate that it would be
better to avoid regfree() upon failed regcomp(), even though such a
situation is handled sanely in some implementations.

[1]: https://www.redhat.com/archives/libvir-list/2013-September/msg00276.html
[2]: https://www.redhat.com/archives/libvir-list/2013-September/msg00273.html

[PATCH 2/1] config: let `config_store_data_clear()` handle `value_regex`

[Martin Ågren]

Instead of carefully clearing up `value_regex` in each code path, let
`config_store_data_clear()` handle that.

Signed-off-by: Martin Ågren 
---
I *think* that it should be ok to `regfree()` after `regcomp()` failed,
but I'll need to look into that some more (and say something about it in
the commit message).

 config.c | 16 +---
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/config.c b/config.c
index 83d7d0851a..2e3c6c94e9 100644
--- a/config.c
+++ b/config.c
@@ -2335,6 +2335,11 @@ struct config_store_data {
 
 void config_store_data_clear(struct config_store_data *store)
 {
+   if (store->value_regex != NULL &&
+   store->value_regex != CONFIG_REGEX_NONE) {
+   regfree(store->value_regex);
+   free(store->value_regex);
+   }
free(store->parsed);
free(store->seen);
memset(store, 0, sizeof(*store));
@@ -2722,7 +2727,6 @@ int git_config_set_multivar_in_file_gently(const char 
*config_filename,
if (regcomp(store.value_regex, value_regex,
REG_EXTENDED)) {
error("invalid pattern: %s", value_regex);
-   free(store.value_regex);
ret = CONFIG_INVALID_PATTERN;
goto out_free;
}
@@ -2748,21 +2752,11 @@ int git_config_set_multivar_in_file_gently(const char 
*config_filename,
  , )) {
error("invalid config file %s", config_filename);
free(store.key);
-   if (store.value_regex != NULL &&
-   store.value_regex != CONFIG_REGEX_NONE) {
-   regfree(store.value_regex);
-   free(store.value_regex);
-   }
ret = CONFIG_INVALID_FILE;
goto out_free;
}
 
free(store.key);
-   if (store.value_regex != NULL &&
-   store.value_regex != CONFIG_REGEX_NONE) {
-   regfree(store.value_regex);
-   free(store.value_regex);
-   }
 
/* if nothing to unset, or too many matches, error out */
if ((store.seen_nr == 0 && value == NULL) ||
-- 
2.17.0.583.g9a75a153ac