support/temp_file.c

   1 /* Temporary file handling for tests.
   2    Copyright (C) 1998-2017 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 /* This is required to get an mkstemp which can create large files on
  20    some 32-bit platforms. */
  21 #define _FILE_OFFSET_BITS 64
  22
  23 #include <support/temp_file.h>
  24 #include <support/temp_file-internal.h>
  25 #include <support/support.h>
  26
  27 #include <paths.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <unistd.h>
  32
  33 /* List of temporary files.  */
  34 static struct temp_name_list
  35 {
  36   struct temp_name_list *next;
  37   char *name;
  38   pid_t owner;
  39 } *temp_name_list;
  40
  41 /* Location of the temporary files.  Set by the test skeleton via
  42    support_set_test_dir.  The string is not be freed.  */
  43 static const char *test_dir = _PATH_TMP;
  44
  45 void
  46 add_temp_file (const char *name)
  47 {
  48   struct temp_name_list *newp
  49     = (struct temp_name_list *) xcalloc (sizeof (*newp), 1);
  50   char *newname = strdup (name);
  51   if (newname != NULL)
  52     {
  53       newp->name = newname;
  54       newp->next = temp_name_list;
  55       newp->owner = getpid ();
  56       temp_name_list = newp;
  57     }
  58   else
  59     free (newp);
  60 }
  61
  62 int
  63 create_temp_file (const char *base, char **filename)
  64 {
  65   char *fname;
  66   int fd;
  67
  68   fname = (char *) xmalloc (strlen (test_dir) + 1 + strlen (base)
  69                             + sizeof ("XXXXXX"));
  70   strcpy (stpcpy (stpcpy (stpcpy (fname, test_dir), "/"), base), "XXXXXX");
  71
  72   fd = mkstemp (fname);
  73   if (fd == -1)
  74     {
  75       printf ("cannot open temporary file '%s': %m\n", fname);
  76       free (fname);
  77       return -1;
  78     }
  79
  80   add_temp_file (fname);
  81   if (filename != NULL)
  82     *filename = fname;
  83   else
  84     free (fname);
  85
  86   return fd;
  87 }
  88
  89 /* Helper functions called by the test skeleton follow.  */
  90
  91 void
  92 support_set_test_dir (const char *path)
  93 {
  94   test_dir = path;
  95 }
  96
  97 void
  98 support_delete_temp_files (void)
  99 {
 100   pid_t pid = getpid ();
 101   while (temp_name_list != NULL)
 102     {
 103       /* Only perform the removal if the path was registed in the same
 104          process, as identified by the PID.  (This assumes that the
 105          parent process which registered the temporary file sticks
 106          around, to prevent PID reuse.)  */
 107       if (temp_name_list->owner == pid)
 108         {
 109           if (remove (temp_name_list->name) != 0)
 110             printf ("warning: could not remove temporary file: %s: %m\n",
 111                     temp_name_list->name);
 112         }
 113       free (temp_name_list->name);
 114
 115       struct temp_name_list *next = temp_name_list->next;
 116       free (temp_name_list);
 117       temp_name_list = next;
 118     }
 119 }
 120
 121 void
 122 support_print_temp_files (FILE *f)
 123 {
 124   if (temp_name_list != NULL)
 125     {
 126       struct temp_name_list *n;
 127       fprintf (f, "temp_files=(\n");
 128       for (n = temp_name_list; n != NULL; n = n->next)
 129         fprintf (f, "  '%s'\n", n->name);
 130       fprintf (f, ")\n");
 131     }
 132 }