diff options
Diffstat (limited to 'sysdeps/posix/tempname.c')
| -rw-r--r-- | sysdeps/posix/tempname.c | 65 |
1 files changed, 43 insertions, 22 deletions
diff --git a/sysdeps/posix/tempname.c b/sysdeps/posix/tempname.c index 7689bb0..536225e 100644 --- a/sysdeps/posix/tempname.c +++ b/sysdeps/posix/tempname.c @@ -27,6 +27,7 @@ #include <fcntl.h> #include <unistd.h> #include <sys/time.h> +#include <assert.h> /* Return nonzero if DIR is an existent directory. */ static int @@ -106,20 +107,27 @@ static const char letters[] = /* Generate a temporary file name based on TMPL. TMPL must match the rules for mk[s]temp (i.e. end in "XXXXXX"). The name constructed does not exist at the time of the call to __gen_tempname. TMPL is - overwritten with the result. If OPENIT is nonzero, creates the - file and returns a read-write fd; the file is mode 0600 modulo - umask. If LARGEFILE is nonzero, uses open64() instead of open(). + overwritten with the result. + + KIND may be one of: + __GT_NOCREATE: simply verify that the name does not exist + at the time of the call. + __GT_FILE: create the file using open(O_CREAT|O_EXCL) + and return a read-write fd. The file is mode 0600. + __GT_BIGFILE: same as __GT_FILE but use open64(). + __GT_DIR: create a directory, which will be mode 0700. We use a clever algorithm to get hard-to-predict names. */ int -__gen_tempname (char *tmpl, int openit, int largefile) +__gen_tempname (char *tmpl, int kind) { int len; char *XXXXXX; static uint64_t value; struct timeval tv; - int count, fd; + int count, fd = -1; int save_errno = errno; + struct stat st; len = strlen (tmpl); if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX")) @@ -152,24 +160,25 @@ __gen_tempname (char *tmpl, int openit, int largefile) v /= 62; XXXXXX[5] = letters[v % 62]; - if (openit) - { - fd = (largefile - ? __open (tmpl, O_RDWR | O_CREAT | O_EXCL, 0600) - : __open64 (tmpl, O_RDWR | O_CREAT | O_EXCL, 0600)); - if (fd >= 0) - { - __set_errno (save_errno); - return fd; - } - else if (errno != EEXIST) - /* Any other error will apply also to other names we might - try, and there are 2^32 or so of them, so give up now. */ - return -1; - } - else + switch (kind) { - struct stat st; + case __GT_FILE: + fd = __open (tmpl, O_RDWR | O_CREAT | O_EXCL, 0600); + break; + + case __GT_BIGFILE: + fd = __open64 (tmpl, O_RDWR | O_CREAT | O_EXCL, 0600); + break; + + case __GT_DIR: + fd = __mkdir (tmpl, 0700); + break; + + case __GT_NOCREATE: + /* This case is backward from the other three. __gen_tempname + succeeds if __xstat fails because the name does not exist. + Note the continue to bypass the common logic at the bottom + of the loop. */ if (__xstat (_STAT_VER, tmpl, &st) < 0) { if (errno == ENOENT) @@ -181,7 +190,19 @@ __gen_tempname (char *tmpl, int openit, int largefile) /* Give up now. */ return -1; } + continue; + + default: + assert (! "invalid KIND in __gen_tempname"); + } + + if (fd >= 0) + { + __set_errno (save_errno); + return fd; } + else if (errno != EEXIST) + return -1; } /* We got out of the loop because we ran out of combinations to try. */ |