diff options
Diffstat (limited to 'libc/misc/internals/tempname.c')
| -rw-r--r-- | libc/misc/internals/tempname.c | 106 |
1 files changed, 64 insertions, 42 deletions
diff --git a/libc/misc/internals/tempname.c b/libc/misc/internals/tempname.c index 41325d998..427c16cb5 100644 --- a/libc/misc/internals/tempname.c +++ b/libc/misc/internals/tempname.c @@ -27,12 +27,14 @@ #include <stdlib.h> #include <string.h> #include <errno.h> -#include <sys/types.h> -#include <sys/stat.h> #include <fcntl.h> #include <unistd.h> +#include <assert.h> +#include <sys/types.h> +#include <sys/stat.h> #include <sys/time.h> + /* Return nonzero if DIR is an existent directory. */ static int direxists (const char *dir) { @@ -46,8 +48,8 @@ static int direxists (const char *dir) for use with mk[s]temp. Will fail (-1) if DIR is non-null and doesn't exist, none of the searched dirs exists, or there's not enough space in TMPL. */ -int __path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx, - int try_tmpdir) +int __path_search (char *tmpl, size_t tmpl_len, const char *dir, + const char *pfx, int try_tmpdir) { //const char *d; size_t dlen, plen; @@ -111,22 +113,28 @@ 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 __gen_tempname (char *tmpl, int kind) { int len; char *XXXXXX; static uint64_t value; struct timeval tv; - uint32_t high, low, rh; - unsigned int k; + uint32_t high, low, rh; + unsigned int k; int count, fd; int save_errno = errno; - int i; + int i; len = strlen (tmpl); if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX")) @@ -148,46 +156,60 @@ int __gen_tempname (char *tmpl, int openit) high = value >> 32; for (i = 0 ; i < 6 ; i++) { - rh = high % 62; - high /= 62; + rh = high % 62; + high /= 62; #define L ((UINT32_MAX % 62 + 1) % 62) - k = (low % 62) + (L * rh); + k = (low % 62) + (L * rh); #undef L #define H ((UINT32_MAX / 62) + ((UINT32_MAX % 62 + 1) / 62)) - low = (low / 62) + (H * rh) + (k / 62); + low = (low / 62) + (H * rh) + (k / 62); #undef H - k %= 62; - XXXXXX[i] = letters[k]; + k %= 62; + XXXXXX[i] = letters[k]; } - if (openit) - { - fd = open (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 - { - struct stat st; - if (stat (tmpl, &st) < 0) - { - if (errno == ENOENT) + switch(kind) { + case __GT_NOCREATE: { - __set_errno (save_errno); - return 0; + struct stat st; + if (stat (tmpl, &st) < 0) + { + if (errno == ENOENT) + { + __set_errno (save_errno); + return 0; + } + else + /* Give up now. */ + return -1; + } + else + continue; } - else - /* Give up now. */ - return -1; - } + case __GT_FILE: + fd = open (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); + break; +#if defined __UCLIBC_HAVE_LFS__ + case __GT_BIGFILE: + fd = open64 (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); + break; +#endif + case __GT_DIR: + fd = mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR); + break; + default: + fd = -1; + assert (! "invalid KIND in __gen_tempname"); } + + 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; } /* We got out of the loop because we ran out of combinations to try. */ |