[v2] time: Remove alloca() from getdate
Checks
Context |
Check |
Description |
dj/TryBot-apply_patch |
success
|
Patch applied to master at the time it was sent
|
dj/TryBot-32bit |
success
|
Build for i686
|
Commit Message
Changes to v1:
* Add error handling for __strndup()
--8<--
Reduce the usage of alloca() to the bare minimum to avoid the potential
for stack overflow. Use __strndup to simplify the code.
---
time/getdate.c | 23 +++++------------------
1 file changed, 5 insertions(+), 18 deletions(-)
Comments
On 2023-04-26 11:22, Joe Simmons-Talbott via Libc-alpha wrote:
> Changes to v1:
> * Add error handling for __strndup()
>
> --8<--
> Reduce the usage of alloca() to the bare minimum to avoid the potential
> for stack overflow. Use __strndup to simplify the code.
> ---
> time/getdate.c | 23 +++++------------------
> 1 file changed, 5 insertions(+), 18 deletions(-)
+1, I don't see a good reason to prematurely optimize this path given
that file operations on $DATEMSK should dominate any profile in this
function.
LGTM.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
>
> diff --git a/time/getdate.c b/time/getdate.c
> index c5c8378707..2f0ebbe097 100644
> --- a/time/getdate.c
> +++ b/time/getdate.c
> @@ -26,7 +26,6 @@
> #include <unistd.h>
> #include <sys/stat.h>
> #include <ctype.h>
> -#include <alloca.h>
>
> #define TM_YEAR_BASE 1900
>
> @@ -153,26 +152,14 @@ __getdate_r (const char *string, struct tm *tp)
>
> if (inlen < oldlen)
> {
> - bool using_malloc = false;
> -
> - if (__libc_use_alloca (inlen + 1))
> - instr = alloca (inlen + 1);
> - else
> + instr = __strndup(string, inlen);
> + if (instr == NULL)
> {
> - instr = malloc (inlen + 1);
> - if (instr == NULL)
> - {
> - fclose (fp);
> - return 6;
> - }
> - using_malloc = true;
> + fclose(fp);
> + return 6;
> }
> - memcpy (instr, string, inlen);
> - instr[inlen] = '\0';
> +
> string = instr;
> -
> - if (!using_malloc)
> - instr = NULL;
> }
>
> line = NULL;
@@ -26,7 +26,6 @@
#include <unistd.h>
#include <sys/stat.h>
#include <ctype.h>
-#include <alloca.h>
#define TM_YEAR_BASE 1900
@@ -153,26 +152,14 @@ __getdate_r (const char *string, struct tm *tp)
if (inlen < oldlen)
{
- bool using_malloc = false;
-
- if (__libc_use_alloca (inlen + 1))
- instr = alloca (inlen + 1);
- else
+ instr = __strndup(string, inlen);
+ if (instr == NULL)
{
- instr = malloc (inlen + 1);
- if (instr == NULL)
- {
- fclose (fp);
- return 6;
- }
- using_malloc = true;
+ fclose(fp);
+ return 6;
}
- memcpy (instr, string, inlen);
- instr[inlen] = '\0';
+
string = instr;
-
- if (!using_malloc)
- instr = NULL;
}
line = NULL;