libiberty/choose-temp.c

   1 /* Utility to pick a temporary filename prefix.
   2    Copyright (C) 1996-2021 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 #ifdef HAVE_UNISTD_H
  27 #include <unistd.h>
  28 #endif
  29 #ifdef HAVE_STDLIB_H
  30 #include <stdlib.h>
  31 #endif
  32 #ifdef HAVE_STRING_H
  33 #include <string.h>
  34 #endif
  35
  36 #include "libiberty.h"
  37
  38 /* Name of temporary file.
  39    mktemp requires 6 trailing X's.  */
  40 #define TEMP_FILE "ccXXXXXX"
  41 #define TEMP_FILE_LEN (sizeof(TEMP_FILE) - 1)
  42
  43 /*
  44
  45 @deftypefn Extension char* choose_temp_base (void)
  46
  47 Return a prefix for temporary file names or @code{NULL} if unable to
  48 find one.  The current directory is chosen if all else fails so the
  49 program is exited if a temporary directory can't be found (@code{mktemp}
  50 fails).  The buffer for the result is obtained with @code{xmalloc}.
  51
  52 This function is provided for backwards compatibility only.  Its use is
  53 not recommended.
  54
  55 @end deftypefn
  56
  57 */
  58
  59 char *
  60 choose_temp_base (void)
  61 {
  62   const char *base = choose_tmpdir ();
  63   char *temp_filename;
  64   int len;
  65
  66   len = strlen (base);
  67   temp_filename = XNEWVEC (char, len + TEMP_FILE_LEN + 1);
  68   strcpy (temp_filename, base);
  69   strcpy (temp_filename + len, TEMP_FILE);
  70
  71   if (mktemp (temp_filename) == 0)
  72     abort ();
  73   return temp_filename;
  74 }