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author | Junio C Hamano <gitster@pobox.com> | 2010-03-08 00:36:00 -0800 |
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committer | Junio C Hamano <gitster@pobox.com> | 2010-03-08 00:36:00 -0800 |
commit | 493e433277ee72b200e72f7a17e08266ed9497c5 (patch) | |
tree | 8db1b524e77ee9d24ed89d22f311f17ff50baf64 /path.c | |
parent | 6ae611fa8d1e15e918e59b7e20abf98643cd25e4 (diff) | |
parent | 5256b006312e4d06e11b49a8b128e9e550e54f31 (diff) | |
download | git-493e433277ee72b200e72f7a17e08266ed9497c5.tar.gz |
Merge branch 'mm/mkstemps-mode-for-packfiles' into maint
* mm/mkstemps-mode-for-packfiles:
Use git_mkstemp_mode instead of plain mkstemp to create object files
git_mkstemps_mode: don't set errno to EINVAL on exit.
Use git_mkstemp_mode and xmkstemp_mode in odb_mkstemp, not chmod later.
git_mkstemp_mode, xmkstemp_mode: variants of gitmkstemps with mode argument.
Move gitmkstemps to path.c
Add a testcase for ACL with restrictive umask.
Diffstat (limited to 'path.c')
-rw-r--r-- | path.c | 79 |
1 files changed, 79 insertions, 0 deletions
@@ -157,6 +157,85 @@ int git_mkstemps(char *path, size_t len, const char *template, int suffix_len) return mkstemps(path, suffix_len); } +/* Adapted from libiberty's mkstemp.c. */ + +#undef TMP_MAX +#define TMP_MAX 16384 + +int git_mkstemps_mode(char *pattern, int suffix_len, int mode) +{ + 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, mode); + 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'; + return -1; +} + +int git_mkstemp_mode(char *pattern, int mode) +{ + /* mkstemp is just mkstemps with no suffix */ + return git_mkstemps_mode(pattern, 0, mode); +} + +int gitmkstemps(char *pattern, int suffix_len) +{ + return git_mkstemps_mode(pattern, suffix_len, 0600); +} + int validate_headref(const char *path) { struct stat st; |