| 1 | /* Utility to pick a temporary filename prefix. |
| 2 | Copyright (C) 1996-2019 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of the libiberty library. |
| 5 | Libiberty is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Library General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2 of the License, or (at your option) any later version. |
| 9 | |
| 10 | Libiberty is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Library General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Library General Public |
| 16 | License along with libiberty; see the file COPYING.LIB. If not, |
| 17 | write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
| 18 | Boston, MA 02110-1301, USA. */ |
| 19 | |
| 20 | #ifdef HAVE_CONFIG_H |
| 21 | #include "config.h" |
| 22 | #endif |
| 23 | |
| 24 | #include <stdio.h> /* May get P_tmpdir. */ |
| 25 | #include <sys/types.h> |
| 26 | #include <errno.h> |
| 27 | #ifdef HAVE_UNISTD_H |
| 28 | #include <unistd.h> |
| 29 | #endif |
| 30 | #ifdef HAVE_STDLIB_H |
| 31 | #include <stdlib.h> |
| 32 | #endif |
| 33 | #ifdef HAVE_STRING_H |
| 34 | #include <string.h> |
| 35 | #endif |
| 36 | #ifdef HAVE_SYS_FILE_H |
| 37 | #include <sys/file.h> /* May get R_OK, etc. on some systems. */ |
| 38 | #endif |
| 39 | #if defined(_WIN32) && !defined(__CYGWIN__) |
| 40 | #include <windows.h> |
| 41 | #endif |
| 42 | |
| 43 | #ifndef R_OK |
| 44 | #define R_OK 4 |
| 45 | #define W_OK 2 |
| 46 | #define X_OK 1 |
| 47 | #endif |
| 48 | |
| 49 | #include "libiberty.h" |
| 50 | extern int mkstemps (char *, int); |
| 51 | |
| 52 | /* '/' works just fine on MS-DOS based systems. */ |
| 53 | #ifndef DIR_SEPARATOR |
| 54 | #define DIR_SEPARATOR '/' |
| 55 | #endif |
| 56 | |
| 57 | /* Name of temporary file. |
| 58 | mktemp requires 6 trailing X's. */ |
| 59 | #define TEMP_FILE "XXXXXX" |
| 60 | #define TEMP_FILE_LEN (sizeof(TEMP_FILE) - 1) |
| 61 | |
| 62 | #if !defined(_WIN32) || defined(__CYGWIN__) |
| 63 | |
| 64 | /* Subroutine of choose_tmpdir. |
| 65 | If BASE is non-NULL, return it. |
| 66 | Otherwise it checks if DIR is a usable directory. |
| 67 | If success, DIR is returned. |
| 68 | Otherwise NULL is returned. */ |
| 69 | |
| 70 | static inline const char *try_dir (const char *, const char *); |
| 71 | |
| 72 | static inline const char * |
| 73 | try_dir (const char *dir, const char *base) |
| 74 | { |
| 75 | if (base != 0) |
| 76 | return base; |
| 77 | if (dir != 0 |
| 78 | && access (dir, R_OK | W_OK | X_OK) == 0) |
| 79 | return dir; |
| 80 | return 0; |
| 81 | } |
| 82 | |
| 83 | static const char tmp[] = { DIR_SEPARATOR, 't', 'm', 'p', 0 }; |
| 84 | static const char usrtmp[] = |
| 85 | { DIR_SEPARATOR, 'u', 's', 'r', DIR_SEPARATOR, 't', 'm', 'p', 0 }; |
| 86 | static const char vartmp[] = |
| 87 | { DIR_SEPARATOR, 'v', 'a', 'r', DIR_SEPARATOR, 't', 'm', 'p', 0 }; |
| 88 | |
| 89 | #endif |
| 90 | |
| 91 | static char *memoized_tmpdir; |
| 92 | |
| 93 | /* |
| 94 | |
| 95 | @deftypefn Replacement const char* choose_tmpdir () |
| 96 | |
| 97 | Returns a pointer to a directory path suitable for creating temporary |
| 98 | files in. |
| 99 | |
| 100 | @end deftypefn |
| 101 | |
| 102 | */ |
| 103 | |
| 104 | const char * |
| 105 | choose_tmpdir (void) |
| 106 | { |
| 107 | if (!memoized_tmpdir) |
| 108 | { |
| 109 | #if !defined(_WIN32) || defined(__CYGWIN__) |
| 110 | const char *base = 0; |
| 111 | char *tmpdir; |
| 112 | unsigned int len; |
| 113 | |
| 114 | #ifdef VMS |
| 115 | /* Try VMS standard temp logical. */ |
| 116 | base = try_dir ("/sys$scratch", base); |
| 117 | #else |
| 118 | base = try_dir (getenv ("TMPDIR"), base); |
| 119 | base = try_dir (getenv ("TMP"), base); |
| 120 | base = try_dir (getenv ("TEMP"), base); |
| 121 | #endif |
| 122 | |
| 123 | #ifdef P_tmpdir |
| 124 | /* We really want a directory name here as if concatenated with say \dir |
| 125 | we do not end up with a double \\ which defines an UNC path. */ |
| 126 | if (strcmp (P_tmpdir, "\\") == 0) |
| 127 | base = try_dir ("\\.", base); |
| 128 | else |
| 129 | base = try_dir (P_tmpdir, base); |
| 130 | #endif |
| 131 | |
| 132 | /* Try /var/tmp, /usr/tmp, then /tmp. */ |
| 133 | base = try_dir (vartmp, base); |
| 134 | base = try_dir (usrtmp, base); |
| 135 | base = try_dir (tmp, base); |
| 136 | |
| 137 | /* If all else fails, use the current directory! */ |
| 138 | if (base == 0) |
| 139 | base = "."; |
| 140 | /* Append DIR_SEPARATOR to the directory we've chosen |
| 141 | and return it. */ |
| 142 | len = strlen (base); |
| 143 | tmpdir = XNEWVEC (char, len + 2); |
| 144 | strcpy (tmpdir, base); |
| 145 | tmpdir[len] = DIR_SEPARATOR; |
| 146 | tmpdir[len+1] = '\0'; |
| 147 | memoized_tmpdir = tmpdir; |
| 148 | #else /* defined(_WIN32) && !defined(__CYGWIN__) */ |
| 149 | DWORD len; |
| 150 | |
| 151 | /* Figure out how much space we need. */ |
| 152 | len = GetTempPath(0, NULL); |
| 153 | if (len) |
| 154 | { |
| 155 | memoized_tmpdir = XNEWVEC (char, len); |
| 156 | if (!GetTempPath(len, memoized_tmpdir)) |
| 157 | { |
| 158 | XDELETEVEC (memoized_tmpdir); |
| 159 | memoized_tmpdir = NULL; |
| 160 | } |
| 161 | } |
| 162 | if (!memoized_tmpdir) |
| 163 | /* If all else fails, use the current directory. */ |
| 164 | memoized_tmpdir = xstrdup (".\\"); |
| 165 | #endif /* defined(_WIN32) && !defined(__CYGWIN__) */ |
| 166 | } |
| 167 | |
| 168 | return memoized_tmpdir; |
| 169 | } |
| 170 | |
| 171 | /* |
| 172 | |
| 173 | @deftypefn Replacement char* make_temp_file (const char *@var{suffix}) |
| 174 | |
| 175 | Return a temporary file name (as a string) or @code{NULL} if unable to |
| 176 | create one. @var{suffix} is a suffix to append to the file name. The |
| 177 | string is @code{malloc}ed, and the temporary file has been created. |
| 178 | |
| 179 | @end deftypefn |
| 180 | |
| 181 | */ |
| 182 | |
| 183 | char * |
| 184 | make_temp_file_with_prefix (const char *prefix, const char *suffix) |
| 185 | { |
| 186 | const char *base = choose_tmpdir (); |
| 187 | char *temp_filename; |
| 188 | int base_len, suffix_len, prefix_len; |
| 189 | int fd; |
| 190 | |
| 191 | if (prefix == 0) |
| 192 | prefix = "cc"; |
| 193 | |
| 194 | if (suffix == 0) |
| 195 | suffix = ""; |
| 196 | |
| 197 | base_len = strlen (base); |
| 198 | prefix_len = strlen (prefix); |
| 199 | suffix_len = strlen (suffix); |
| 200 | |
| 201 | temp_filename = XNEWVEC (char, base_len |
| 202 | + TEMP_FILE_LEN |
| 203 | + suffix_len |
| 204 | + prefix_len + 1); |
| 205 | strcpy (temp_filename, base); |
| 206 | strcpy (temp_filename + base_len, prefix); |
| 207 | strcpy (temp_filename + base_len + prefix_len, TEMP_FILE); |
| 208 | strcpy (temp_filename + base_len + prefix_len + TEMP_FILE_LEN, suffix); |
| 209 | |
| 210 | fd = mkstemps (temp_filename, suffix_len); |
| 211 | /* Mkstemps failed. It may be EPERM, ENOSPC etc. */ |
| 212 | if (fd == -1) |
| 213 | { |
| 214 | fprintf (stderr, "Cannot create temporary file in %s: %s\n", |
| 215 | base, strerror (errno)); |
| 216 | abort (); |
| 217 | } |
| 218 | /* We abort on failed close out of sheer paranoia. */ |
| 219 | if (close (fd)) |
| 220 | abort (); |
| 221 | return temp_filename; |
| 222 | } |
| 223 | |
| 224 | char * |
| 225 | make_temp_file (const char *suffix) |
| 226 | { |
| 227 | return make_temp_file_with_prefix (NULL, suffix); |
| 228 | } |