sergiotarxz/nuttx
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

mkstemp: Only look at the trailing Xs

Browse Source 
As it's stated in the standards.

The original code look at the first Xs. It can end up with
an unexpected behavior, if a template contains multiple series of Xs.
E.g. /tmp/XXXXXX/XXXXXX
This commit is contained in:
YAMAMOTO Takashi 2020-06-16 17:21:28 +09:00 committed by Xiang Xiao
parent ae92afd250
commit 66052f7c4c
1 changed files with 6 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
libs/libc/stdlib/lib_mkstemp.c
View File

@ -198,29 +198,28 @@ int mkstemp(FAR char *path_template)
uint8_t base62[MAX_XS];
uint32_t retries;
FAR char *xptr;
FAR char *ptr;
int xlen;
int fd;
int i;
/* Count the number of X's at the end of the template */
xptr = strchr(path_template, 'X');
if (!xptr)
xptr = &path_template[strlen(path_template)];
for (xlen = 0; xlen < MAX_XS && path_template < xptr && *(xptr - 1) == 'X';
xlen++, xptr--);
if (xlen == 0)
{
/* No Xs? There should always really be 6 */
return open(path_template, O_RDWR | O_CREAT | O_EXCL, 0666);
}
/* There is at least one.. count all of them */
for (xlen = 0, ptr = xptr; xlen < MAX_XS && *ptr == 'X'; xlen++, ptr++);
/* Ignore any X's after the sixth */
if (xlen > MAX_XS)
{
xptr += xlen - MAX_XS;
xlen = MAX_XS;
}