Browse Source
mkstemps() is a BSD extension so provide an implementation for cross-platform use. Signed-off-by: David Aguilar <davvid@gmail.com> Tested-by: Johannes Sixt <j6t@kdbg.org> (Windows) Signed-off-by: Junio C Hamano <gitster@pobox.com>maint
David Aguilar
16 years ago
committed by
Junio C Hamano
5 changed files with 102 additions and 0 deletions
@ -0,0 +1,70 @@
@@ -0,0 +1,70 @@
|
||||
#include "../git-compat-util.h" |
||||
|
||||
/* Adapted from libiberty's mkstemp.c. */ |
||||
|
||||
#undef TMP_MAX |
||||
#define TMP_MAX 16384 |
||||
|
||||
int gitmkstemps(char *pattern, int suffix_len) |
||||
{ |
||||
static const char letters[] = |
||||
"abcdefghijklmnopqrstuvwxyz" |
||||
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" |
||||
"0123456789"; |
||||
static const int num_letters = 62; |
||||
uint64_t value; |
||||
struct timeval tv; |
||||
char *template; |
||||
size_t len; |
||||
int fd, count; |
||||
|
||||
len = strlen(pattern); |
||||
|
||||
if (len < 6 + suffix_len) { |
||||
errno = EINVAL; |
||||
return -1; |
||||
} |
||||
|
||||
if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) { |
||||
errno = EINVAL; |
||||
return -1; |
||||
} |
||||
|
||||
/* |
||||
* Replace pattern's XXXXXX characters with randomness. |
||||
* Try TMP_MAX different filenames. |
||||
*/ |
||||
gettimeofday(&tv, NULL); |
||||
value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid(); |
||||
template = &pattern[len - 6 - suffix_len]; |
||||
for (count = 0; count < TMP_MAX; ++count) { |
||||
uint64_t v = value; |
||||
/* Fill in the random bits. */ |
||||
template[0] = letters[v % num_letters]; v /= num_letters; |
||||
template[1] = letters[v % num_letters]; v /= num_letters; |
||||
template[2] = letters[v % num_letters]; v /= num_letters; |
||||
template[3] = letters[v % num_letters]; v /= num_letters; |
||||
template[4] = letters[v % num_letters]; v /= num_letters; |
||||
template[5] = letters[v % num_letters]; v /= num_letters; |
||||
|
||||
fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, 0600); |
||||
if (fd > 0) |
||||
return fd; |
||||
/* |
||||
* Fatal error (EPERM, ENOSPC etc). |
||||
* It doesn't make sense to loop. |
||||
*/ |
||||
if (errno != EEXIST) |
||||
break; |
||||
/* |
||||
* This is a random value. It is only necessary that |
||||
* the next TMP_MAX values generated by adding 7777 to |
||||
* VALUE are different with (module 2^32). |
||||
*/ |
||||
value += 7777; |
||||
} |
||||
/* We return the null string if we can't find a unique file name. */ |
||||
pattern[0] = '\0'; |
||||
errno = EINVAL; |
||||
return -1; |
||||
} |
||||
Loading…
Reference in new issue