1 /* Utility to pick a temporary filename prefix. 2 Copyright (C) 1996, 1997, 1998, 2001, 2009, 2010 3 Free Software Foundation, Inc. 4 5 This file is part of the libiberty library. 6 Libiberty is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Library General Public 8 License as published by the Free Software Foundation; either 9 version 2 of the License, or (at your option) any later version. 10 11 Libiberty is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Library General Public License for more details. 15 16 You should have received a copy of the GNU Library General Public 17 License along with libiberty; see the file COPYING.LIB. If not, 18 write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, 19 Boston, MA 02110-1301, USA. */ 20 21 #ifdef HAVE_CONFIG_H 22 #include "config.h" 23 #endif 24 25 #include <stdio.h> /* May get P_tmpdir. */ 26 #include <sys/types.h> 27 #include <errno.h> 28 #ifdef HAVE_UNISTD_H 29 #include <unistd.h> 30 #endif 31 #ifdef HAVE_STDLIB_H 32 #include <stdlib.h> 33 #endif 34 #ifdef HAVE_STRING_H 35 #include <string.h> 36 #endif 37 #ifdef HAVE_SYS_FILE_H 38 #include <sys/file.h> /* May get R_OK, etc. on some systems. */ 39 #endif 40 #if defined(_WIN32) && !defined(__CYGWIN__) 41 #include <windows.h> 42 #endif 43 44 #ifndef R_OK 45 #define R_OK 4 46 #define W_OK 2 47 #define X_OK 1 48 #endif 49 50 #include "libiberty.h" 51 extern int mkstemps (char *, int); 52 53 /* '/' works just fine on MS-DOS based systems. */ 54 #ifndef DIR_SEPARATOR 55 #define DIR_SEPARATOR '/' 56 #endif 57 58 /* Name of temporary file. 59 mktemp requires 6 trailing X's. */ 60 #define TEMP_FILE "ccXXXXXX" 61 #define TEMP_FILE_LEN (sizeof(TEMP_FILE) - 1) 62 63 #if !defined(_WIN32) || defined(__CYGWIN__) 64 65 /* Subroutine of choose_tmpdir. 66 If BASE is non-NULL, return it. 67 Otherwise it checks if DIR is a usable directory. 68 If success, DIR is returned. 69 Otherwise NULL is returned. */ 70 71 static inline const char *try_dir (const char *, const char *); 72 73 static inline const char * 74 try_dir (const char *dir, const char *base) 75 { 76 if (base != 0) 77 return base; 78 if (dir != 0 79 && access (dir, R_OK | W_OK | X_OK) == 0) 80 return dir; 81 return 0; 82 } 83 84 static const char tmp[] = { DIR_SEPARATOR, 't', 'm', 'p', 0 }; 85 static const char usrtmp[] = 86 { DIR_SEPARATOR, 'u', 's', 'r', DIR_SEPARATOR, 't', 'm', 'p', 0 }; 87 static const char vartmp[] = 88 { DIR_SEPARATOR, 'v', 'a', 'r', DIR_SEPARATOR, 't', 'm', 'p', 0 }; 89 90 #endif 91 92 static char *memoized_tmpdir; 93 94 /* 95 96 @deftypefn Replacement const char* choose_tmpdir () 97 98 Returns a pointer to a directory path suitable for creating temporary 99 files in. 100 101 @end deftypefn 102 103 */ 104 105 const char * 106 choose_tmpdir (void) 107 { 108 if (!memoized_tmpdir) 109 { 110 #if !defined(_WIN32) || defined(__CYGWIN__) 111 const char *base = 0; 112 char *tmpdir; 113 unsigned int len; 114 115 #ifdef VMS 116 /* Try VMS standard temp logical. */ 117 base = try_dir ("/sys$scratch", base); 118 #else 119 base = try_dir (getenv ("TMPDIR"), base); 120 base = try_dir (getenv ("TMP"), base); 121 base = try_dir (getenv ("TEMP"), base); 122 #endif 123 124 #ifdef P_tmpdir 125 /* We really want a directory name here as if concatenated with say \dir 126 we do not end up with a double \\ which defines an UNC path. */ 127 if (strcmp (P_tmpdir, "\\") == 0) 128 base = try_dir ("\\.", base); 129 else 130 base = try_dir (P_tmpdir, base); 131 #endif 132 133 /* Try /var/tmp, /usr/tmp, then /tmp. */ 134 base = try_dir (vartmp, base); 135 base = try_dir (usrtmp, base); 136 base = try_dir (tmp, base); 137 138 /* If all else fails, use the current directory! */ 139 if (base == 0) 140 base = "."; 141 /* Append DIR_SEPARATOR to the directory we've chosen 142 and return it. */ 143 len = strlen (base); 144 tmpdir = XNEWVEC (char, len + 2); 145 strcpy (tmpdir, base); 146 tmpdir[len] = DIR_SEPARATOR; 147 tmpdir[len+1] = '\0'; 148 memoized_tmpdir = tmpdir; 149 #else /* defined(_WIN32) && !defined(__CYGWIN__) */ 150 DWORD len; 151 152 /* Figure out how much space we need. */ 153 len = GetTempPath(0, NULL); 154 if (len) 155 { 156 memoized_tmpdir = XNEWVEC (char, len); 157 if (!GetTempPath(len, memoized_tmpdir)) 158 { 159 XDELETEVEC (memoized_tmpdir); 160 memoized_tmpdir = NULL; 161 } 162 } 163 if (!memoized_tmpdir) 164 /* If all else fails, use the current directory. */ 165 memoized_tmpdir = xstrdup (".\\"); 166 #endif /* defined(_WIN32) && !defined(__CYGWIN__) */ 167 } 168 169 return memoized_tmpdir; 170 } 171 172 /* 173 174 @deftypefn Replacement char* make_temp_file (const char *@var{suffix}) 175 176 Return a temporary file name (as a string) or @code{NULL} if unable to 177 create one. @var{suffix} is a suffix to append to the file name. The 178 string is @code{malloc}ed, and the temporary file has been created. 179 180 @end deftypefn 181 182 */ 183 184 char * 185 make_temp_file (const char *suffix) 186 { 187 const char *base = choose_tmpdir (); 188 char *temp_filename; 189 int base_len, suffix_len; 190 int fd; 191 192 if (suffix == 0) 193 suffix = ""; 194 195 base_len = strlen (base); 196 suffix_len = strlen (suffix); 197 198 temp_filename = XNEWVEC (char, base_len 199 + TEMP_FILE_LEN 200 + suffix_len + 1); 201 strcpy (temp_filename, base); 202 strcpy (temp_filename + base_len, TEMP_FILE); 203 strcpy (temp_filename + base_len + TEMP_FILE_LEN, suffix); 204 205 fd = mkstemps (temp_filename, suffix_len); 206 /* Mkstemps failed. It may be EPERM, ENOSPC etc. */ 207 if (fd == -1) 208 { 209 fprintf (stderr, "Cannot create temporary file in %s: %s\n", 210 base, strerror (errno)); 211 abort (); 212 } 213 /* We abort on failed close out of sheer paranoia. */ 214 if (close (fd)) 215 abort (); 216 return temp_filename; 217 } 218
