[Mesa-dev] [PATCH] glsl/cache: correct asprintf error handling

[Iago Toral]

Reviewed-by: Iago Toral Quiroga <itoral at igalia.com>

On Thu, 2016-11-03 at 11:03 +0100, Nicolai Hähnle wrote:
> From: Nicolai Hähnle <nicolai.haehnle at amd.com>
> 
> From the manpage of asprintf:
> 
>    "If memory allocation wasn't possible, or some other error occurs,
>     these functions will return -1, and the contents of strp are
>     undefined."
> ---
>  src/compiler/glsl/cache.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/src/compiler/glsl/cache.c b/src/compiler/glsl/cache.c
> index 64a34f0..e74c27d 100644
> --- a/src/compiler/glsl/cache.c
> +++ b/src/compiler/glsl/cache.c
> @@ -409,21 +409,22 @@ choose_random_file_matching(const char
> *dir_path,
>           break;
>  
>        count++;
>     }
>  
>     if (entry == NULL) {
>        closedir(dir);
>        return NULL;
>     }
>  
> -   asprintf(&filename, "%s/%s", dir_path, entry->d_name);
> +   if (asprintf(&filename, "%s/%s", dir_path, entry->d_name) < 0)
> +      filename = NULL;
>  
>     closedir(dir);
>  
>     return filename;
>  }
>  
>  /* Is entry a regular file, and not having a name with a trailing
>   * ".tmp"
>   */
>  static bool
> @@ -490,22 +491,21 @@ evict_random_item(struct program_cache *cache)
>     int a, b;
>     size_t size;
>  
>     /* With a reasonably-sized, full cache, (and with keys generated
>      * from a cryptographic hash), we can choose two random hex
> digits
>      * and reasonably expect the directory to exist with a file in
> it.
>      */
>     a = rand() % 16;
>     b = rand() % 16;
>  
> -   asprintf (&dir_path, "%s/%c%c", cache->path, hex[a], hex[b]);
> -   if (dir_path == NULL)
> +   if (asprintf(&dir_path, "%s/%c%c", cache->path, hex[a], hex[b]) <
> 0)
>        return;
>  
>     size = unlink_random_file_from_directory(dir_path);
>  
>     free(dir_path);
>  
>     if (size) {
>        p_atomic_add(cache->size, - size);
>        return;
>     }