diff options
Diffstat (limited to 'lib/tmpdir.c')
| -rw-r--r-- | lib/tmpdir.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/lib/tmpdir.c b/lib/tmpdir.c new file mode 100644 index 0000000..3e47875 --- /dev/null +++ b/lib/tmpdir.c @@ -0,0 +1,165 @@ +/* Copyright (C) 1999, 2001-2002, 2006, 2009-2022 Free Software Foundation, + Inc. + This file is part of the GNU C Library. + + This file is free software: you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation, either version 3 of the + License, or (at your option) any later version. + + This file is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* Extracted from sysdeps/posix/tempname.c. */ + +#include <config.h> + +/* Specification. */ +#include "tmpdir.h" + +#include <stdbool.h> +#include <stdlib.h> +#include <string.h> + +#include <errno.h> +#ifndef __set_errno +# define __set_errno(Val) errno = (Val) +#endif + +#include <stdio.h> +#ifndef P_tmpdir +# ifdef _P_tmpdir /* native Windows */ +# define P_tmpdir _P_tmpdir +# else +# define P_tmpdir "/tmp" +# endif +#endif + +#include <sys/stat.h> + +#if defined _WIN32 && ! defined __CYGWIN__ +# define WIN32_LEAN_AND_MEAN /* avoid including junk */ +# include <windows.h> +#endif + +#include "pathmax.h" + +#if defined _WIN32 && ! defined __CYGWIN__ +/* Don't assume that UNICODE is not defined. */ +# undef GetTempPath +# define GetTempPath GetTempPathA +#endif + +#if _LIBC +# define struct_stat64 struct stat64 +#else +# define struct_stat64 struct stat +# define __libc_secure_getenv secure_getenv +# define __xstat64(version, path, buf) stat (path, buf) +#endif + +/* Pathname support. + ISSLASH(C) tests whether C is a directory separator character. + */ +#if defined _WIN32 || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__ + /* Native Windows, Cygwin, OS/2, DOS */ +# define ISSLASH(C) ((C) == '/' || (C) == '\\') +#else + /* Unix */ +# define ISSLASH(C) ((C) == '/') +#endif + + +/* Return nonzero if DIR is an existent directory. */ +static bool +direxists (const char *dir) +{ + struct_stat64 buf; + return __xstat64 (_STAT_VER, dir, &buf) == 0 && S_ISDIR (buf.st_mode); +} + +/* Path search algorithm, for tmpnam, tmpfile, etc. If DIR is + non-null and exists, uses it; otherwise uses the first of $TMPDIR, + P_tmpdir, /tmp that exists. Copies into TMPL a template suitable + 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, + bool try_tmpdir) +{ + const char *d; + size_t dlen, plen; + bool add_slash; + + if (!pfx || !pfx[0]) + { + pfx = "file"; + plen = 4; + } + else + { + plen = strlen (pfx); + if (plen > 5) + plen = 5; + } + + if (try_tmpdir) + { + d = __libc_secure_getenv ("TMPDIR"); + if (d != NULL && direxists (d)) + dir = d; + else if (dir != NULL && direxists (dir)) + /* nothing */ ; + else + dir = NULL; + } + if (dir == NULL) + { +#if defined _WIN32 && ! defined __CYGWIN__ + char dirbuf[PATH_MAX]; + DWORD retval; + + /* Find Windows temporary file directory. + We try this before P_tmpdir because Windows defines P_tmpdir to "\\" + and will therefore try to put all temporary files in the root + directory (unless $TMPDIR is set). */ + retval = GetTempPath (PATH_MAX, dirbuf); + if (retval > 0 && retval < PATH_MAX && direxists (dirbuf)) + dir = dirbuf; + else +#endif + if (direxists (P_tmpdir)) + dir = P_tmpdir; + else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp")) + dir = "/tmp"; + else + { + __set_errno (ENOENT); + return -1; + } + } + + dlen = strlen (dir); +#ifdef __VMS + add_slash = 0; +#else + add_slash = dlen != 0 && !ISSLASH (dir[dlen - 1]); +#endif + + /* check we have room for "${dir}/${pfx}XXXXXX\0" */ + if (tmpl_len < dlen + add_slash + plen + 6 + 1) + { + __set_errno (EINVAL); + return -1; + } + + memcpy (tmpl, dir, dlen); + sprintf (tmpl + dlen, &"/%.*sXXXXXX"[!add_slash], (int) plen, pfx); + return 0; +} |