stdio-common/tst-fmemopen2.c

   1 /* fmemopen tests.
   2    Copyright (C) 2015-2024 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    <https://www.gnu.org/licenses/>.  */
  18
  19
  20 #include <assert.h>
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <sys/types.h>
  24 #include <stdint.h>
  25 #include <errno.h>
  26
  27 /* Check fmemopen with user provided buffer open for write.  */
  28 static int
  29 do_test_with_buffer (void)
  30 {
  31   int result = 0;
  32   char buf[100];
  33   const size_t nbuf = sizeof (buf);
  34
  35   FILE *fp = fmemopen (buf, nbuf, "w");
  36   if (fp == NULL)
  37     {
  38       printf ("FAIL: fmemopen failed (%s)\n", __FUNCTION__);
  39       return 1;
  40     }
  41
  42   /* Default write operation, check if file position is correct after it.  */
  43   static const char str[] = "hello world";
  44   const size_t nstr = sizeof (str) - 1;
  45   fputs (str, fp);
  46   off_t o = ftello (fp);
  47   if (o != nstr)
  48     {
  49       printf ("FAIL: first ftello returned %jd, expected %zu\n",
  50               (intmax_t)o, nstr);
  51       result = 1;
  52     }
  53
  54   /* Rewind stream and seek tests, the position size should be equal to
  55      buffer size provided in open function.  */
  56   rewind (fp);
  57   o = ftello (fp);
  58   if (o != 0)
  59     {
  60       printf ("FAIL: second ftello returned %jd, expected 0\n",
  61               (intmax_t)o);
  62       result = 1;
  63     }
  64   if (fseeko (fp, 0, SEEK_END) != 0)
  65     {
  66       printf ("FAIL: fseeko failed\n");
  67       result = 1;
  68     }
  69   o = ftello (fp);
  70   if (o != nstr)
  71     {
  72       printf ("FAIL: third ftello returned %jd, expected %zu\n",
  73               (intmax_t)o, nstr);
  74       result = 1;
  75     }
  76
  77   /* Rewind the stream and recheck by using a shorter string.  */
  78   rewind (fp);
  79   static const char str2[] = "just hello";
  80   const size_t nstr2 = sizeof (str2) - 1;
  81   assert (nstr2 < nstr);
  82   fputs (str2, fp);
  83   o = ftello (fp);
  84   if (o != nstr2)
  85     {
  86       printf ("FAIL: fourth ftello returned %jd, expected %zu\n",
  87               (intmax_t)o, nstr2);
  88       result = 1;
  89     }
  90   fclose (fp);
  91
  92   /* Again, but now with a larger string.  */
  93   static const char str3[] = "just hellod";
  94   if (strcmp (buf, str3) != 0)
  95     {
  96       printf ("FAIL: final string is \"%s\", expected \"%s\"\n",
  97               buf, str3);
  98       result = 1;
  99     }
 100   return result;
 101 }
 102
 103 /* Check fmemopen without user provided buffer open for write.  */
 104 static int
 105 do_test_without_buffer (void)
 106 {
 107   int result = 0;
 108   const size_t nbuf = 100;
 109
 110   FILE *fp = fmemopen (NULL, nbuf, "w");
 111   if (fp == NULL)
 112     {
 113       printf ("FAIL: fmemopen failed (%s)\n", __FUNCTION__);
 114       return 1;
 115     }
 116
 117   static const char str[] = "hello world";
 118   const size_t nstr = sizeof (str) - 1;
 119
 120   /* Default write operation, check if file position is correct after it.  */
 121   fputs (str, fp);
 122   off_t o = ftello (fp);
 123   if (o != nstr)
 124     {
 125       printf ("FAIL: first ftello returned %jd, expected %zu\n",
 126               (intmax_t) o, nstr);
 127       result = 1;
 128     }
 129   if (fseeko (fp, 0, SEEK_END) != 0)
 130     {
 131       printf ("FAIL: fseeko failed\n");
 132       result = 1;
 133     }
 134   o = ftello (fp);
 135   if (o != nstr)
 136     {
 137       printf ("FAIL: second ftello returned %jd, expected %zu\n",
 138               (intmax_t) o, nbuf);
 139       result = 1;
 140     }
 141
 142   /* Rewind the stream and recheck by using a shorter string.  */
 143   rewind (fp);
 144   static const char str2[] = "just hello";
 145   const size_t nstr2 = sizeof (str2) - 1;
 146   assert (nstr2 < nstr);
 147   fputs (str2, fp);
 148   o = ftello (fp);
 149   if (o != nstr2)
 150     {
 151       printf ("FAIL: third ftello returned %jd, expected %zu\n",
 152               (intmax_t) o, nstr2);
 153       result = 1;
 154     }
 155   fclose (fp);
 156
 157   return result;
 158 }
 159
 160 /* Check fmemopen with a buffer length of zero.  */
 161 static int
 162 do_test_length_zero (void)
 163 {
 164   int result = 0;
 165   FILE *fp;
 166 #define BUFCONTENTS "testing buffer"
 167   char buf[100] = BUFCONTENTS;
 168   const size_t nbuf = 0;
 169   int r;
 170
 171   fp = fmemopen (buf, nbuf, "r");
 172   if (fp == NULL)
 173     {
 174       printf ("FAIL: fmemopen failed (%s)\n", __FUNCTION__);
 175       return 1;
 176     }
 177
 178   /* Reading any data on a zero-length buffer should return EOF.  */
 179   if ((r = fgetc (fp)) != EOF)
 180     {
 181       printf ("FAIL: fgetc on a zero-length returned: %d\n", r);
 182       result = 1;
 183     }
 184   off_t o = ftello (fp);
 185   if (o != 0)
 186     {
 187       printf ("FAIL: first ftello returned %jd, expected 0\n",
 188               (intmax_t) o);
 189       result = 1;
 190     }
 191   fclose (fp);
 192
 193   /* Writing any data shall start at current position and shall not pass
 194      current buffer size beyond the size in fmemopen call.  */
 195   fp = fmemopen (buf, nbuf, "w");
 196   if (fp == NULL)
 197     {
 198       printf ("FAIL: second fmemopen failed (%s)\n", __FUNCTION__);
 199       return 1;
 200     }
 201
 202   static const char str[] = "hello world";
 203   /* Because of buffering, the fputs call itself will not fail. However the
 204      final buffer should be not changed because length 0 was passed to the
 205      fmemopen call.  */
 206   fputs (str, fp);
 207   r = 0;
 208   errno = 0;
 209   if (fflush (fp) != EOF)
 210     {
 211       printf ("FAIL: fflush did not return EOF\n");
 212       fclose (fp);
 213       return 1;
 214     }
 215   if (errno != ENOSPC)
 216     {
 217       printf ("FAIL: errno is %i (expected ENOSPC)\n", errno);
 218       fclose (fp);
 219       return 1;
 220     }
 221
 222   fclose (fp);
 223
 224   if (strcmp (buf, BUFCONTENTS) != 0)
 225     {
 226       printf ("FAIL: strcmp (%s, %s) failed\n", buf, BUFCONTENTS);
 227       return 1;
 228     }
 229
 230   /* Different than 'w' mode, 'w+' truncates the buffer.  */
 231   fp = fmemopen (buf, nbuf, "w+");
 232   if (fp == NULL)
 233     {
 234       printf ("FAIL: third fmemopen failed (%s)\n", __FUNCTION__);
 235       return 1;
 236     }
 237
 238   fclose (fp);
 239
 240   if (strcmp (buf, "") != 0)
 241     {
 242       printf ("FAIL: strcmp (%s, \"\") failed\n", buf);
 243       return 1;
 244     }
 245
 246   return result;
 247 }
 248
 249 static int
 250 do_test (void)
 251 {
 252   int ret = 0;
 253
 254   ret += do_test_with_buffer ();
 255   ret += do_test_without_buffer ();
 256   ret += do_test_length_zero ();
 257
 258   return ret;
 259 }
 260
 261 #define TEST_FUNCTION do_test ()
 262 #include "../test-skeleton.c"