diff options
Diffstat (limited to 'lib/tempname.c')
| -rw-r--r-- | lib/tempname.c | 120 |
1 files changed, 51 insertions, 69 deletions
diff --git a/lib/tempname.c b/lib/tempname.c index da0c41c16..f0f7e7f29 100644 --- a/lib/tempname.c +++ b/lib/tempname.c @@ -1,6 +1,6 @@ /* tempname.c - generate the name of a temporary file. - Copyright (C) 1991-2003, 2005-2007, 2009-2015 Free Software Foundation, Inc. + Copyright (C) 1991-2003, 2005-2007, 2009-2014 Free Software Foundation, Inc. This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by @@ -62,7 +62,6 @@ # define struct_stat64 struct stat64 #else # define struct_stat64 struct stat -# define __try_tempname try_tempname # define __gen_tempname gen_tempname # define __getpid getpid # define __gettimeofday gettimeofday @@ -177,9 +176,21 @@ __path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx, static const char letters[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; +/* Generate a temporary file name based on TMPL. TMPL must match the + rules for mk[s]temp (i.e. end in "XXXXXX", possibly with a suffix). + The name constructed does not exist at the time of the call to + __gen_tempname. TMPL is 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_DIR: create a directory, which will be mode 0700. + + We use a clever algorithm to get hard-to-predict names. */ int -__try_tempname (char *tmpl, int suffixlen, void *args, - int (*tryfunc) (char *, void *)) +__gen_tempname (char *tmpl, int suffixlen, int flags, int kind) { int len; char *XXXXXX; @@ -188,6 +199,7 @@ __try_tempname (char *tmpl, int suffixlen, void *args, unsigned int count; int fd = -1; int save_errno = errno; + struct_stat64 st; /* A lower bound on the number of temporary files to attempt to generate. The maximum total number of temporary file names that @@ -244,7 +256,41 @@ __try_tempname (char *tmpl, int suffixlen, void *args, v /= 62; XXXXXX[5] = letters[v % 62]; - fd = tryfunc (tmpl, args); + switch (kind) + { + case __GT_FILE: + fd = __open (tmpl, + (flags & ~O_ACCMODE) + | O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); + break; + + case __GT_DIR: + fd = __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR); + 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 (__lxstat64 (_STAT_VER, tmpl, &st) < 0) + { + if (errno == ENOENT) + { + __set_errno (save_errno); + return 0; + } + else + /* Give up now. */ + return -1; + } + continue; + + default: + assert (! "invalid KIND in __gen_tempname"); + abort (); + } + if (fd >= 0) { __set_errno (save_errno); @@ -258,67 +304,3 @@ __try_tempname (char *tmpl, int suffixlen, void *args, __set_errno (EEXIST); return -1; } - -static int -try_file (char *tmpl, void *flags) -{ - int *openflags = flags; - return __open (tmpl, - (*openflags & ~O_ACCMODE) - | O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); -} - -static int -try_dir (char *tmpl, void *flags _GL_UNUSED) -{ - return __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR); -} - -static int -try_nocreate (char *tmpl, void *flags _GL_UNUSED) -{ - struct_stat64 st; - - if (__lxstat64 (_STAT_VER, tmpl, &st) == 0) - __set_errno (EEXIST); - return errno == ENOENT ? 0 : -1; -} - -/* Generate a temporary file name based on TMPL. TMPL must match the - rules for mk[s]temp (i.e. end in "XXXXXX", possibly with a suffix). - The name constructed does not exist at the time of the call to - __gen_tempname. TMPL is 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_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 suffixlen, int flags, int kind) -{ - int (*tryfunc) (char *, void *); - - switch (kind) - { - case __GT_FILE: - tryfunc = try_file; - break; - - case __GT_DIR: - tryfunc = try_dir; - break; - - case __GT_NOCREATE: - tryfunc = try_nocreate; - break; - - default: - assert (! "invalid KIND in __gen_tempname"); - abort (); - } - return __try_tempname (tmpl, suffixlen, &flags, tryfunc); -} |