tests/framework/tst_preload_FILE.c

   1 /*****************************************************************************
   2  * This file is part of gfxprim library.                                     *
   3  *                                                                           *
   4  * Gfxprim is free software; you can redistribute it and/or                  *
   5  * modify it under the terms of the GNU Lesser General Public                *
   6  * License as published by the Free Software Foundation; either              *
   7  * version 2.1 of the License, or (at your option) any later version.        *
   8  *                                                                           *
   9  * Gfxprim is distributed in the hope that it will be useful,                *
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
  12  * Lesser General Public License for more details.                           *
  13  *                                                                           *
  14  * You should have received a copy of the GNU Lesser General Public          *
  15  * License along with gfxprim; if not, write to the Free Software            *
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                        *
  17  * Boston, MA  02110-1301  USA                                               *
  18  *                                                                           *
  19  * Copyright (C) 2009-2012 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23 #define _GNU_SOURCE
  24 #include <stdio.h>
  25 #include <dlfcn.h>
  26 #include <errno.h>
  27 #include <string.h>
  28
  29 #include "tst_test.h"
  30 #include "tst_preload_FILE.h"
  31
  32 struct tst_fail_FILE *failures = NULL;
  33
  34 void tst_fail_FILE_register(struct tst_fail_FILE *self)
  35 {
  36         failures = self;
  37 }
  38
  39 static struct tst_fail_FILE *failure_by_path(const char *path,
  40                                              enum tst_file_call call)
  41 {
  42         unsigned int i;
  43
  44         if (failures == NULL)
  45                 return NULL;
  46
  47         for (i = 0; failures[i].path != NULL; i++)
  48                 if (failures[i].call == call &&
  49                     !strcmp(path, failures[i].path))
  50                         return &failures[i];
  51
  52         return NULL;
  53 }
  54
  55 void failures_init_FILE(const char *path, FILE *f)
  56 {
  57         unsigned int i;
  58
  59         if (failures == NULL)
  60                 return;
  61
  62         //TODO: warn on f not NULL
  63         for (i = 0; failures[i].path != NULL; i++)
  64                 if (!strcmp(path, failures[i].path))
  65                         failures[i].f = f;
  66 }
  67
  68 static struct tst_fail_FILE *failure_by_FILE(FILE *f, enum tst_file_call call)
  69 {
  70         unsigned int i;
  71
  72         if (failures == NULL)
  73                 return NULL;
  74
  75         for (i = 0; failures[i].path != NULL; i++)
  76                 if (failures[i].call == call && f == failures[i].f)
  77                         return &failures[i];
  78
  79         return NULL;
  80 }
  81
  82 FILE *fopen(const char *path, const char *mode)
  83 {
  84         static FILE *(*real_fopen)(const char *, const char *);
  85
  86         if (!real_fopen)
  87                 real_fopen = dlsym(RTLD_NEXT, "fopen");
  88
  89         struct tst_fail_FILE *failure = failure_by_path(path, TST_FAIL_FOPEN);
  90
  91         if (failure) {
  92                 if (failure->err)
  93                         errno = failure->err;
  94
  95                 return NULL;
  96         }
  97
  98
  99         FILE *f = real_fopen(path, mode);
 100
 101         failures_init_FILE(path, f);
 102
 103         return f;
 104 }
 105
 106 int fclose(FILE *fp)
 107 {
 108         static int (*real_fclose)(FILE *);
 109
 110         if (!real_fclose)
 111                 real_fclose = dlsym(RTLD_NEXT, "fclose");
 112
 113         struct tst_fail_FILE *failure = failure_by_FILE(fp, TST_FAIL_FCLOSE);
 114
 115         /*
 116          * We close the file here correctly, we can because when fclose() has
 117          * failed any further access results in undefined behavior.
 118          */
 119         if (failure) {
 120                 real_fclose(fp);
 121
 122                 if (failure->err)
 123                         errno = failure->err;
 124
 125                 return EOF;
 126         }
 127
 128         return real_fclose(fp);
 129 }