tests/test-ptsname_r.c

   1 /* Test of ptsname_r(3).
   2    Copyright (C) 2010-2025 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Don't use __attribute__ __nonnull__ in this compilation unit.  Otherwise gcc
  18    may "optimize" the null_ptr function, when its result gets passed to a
  19    function that has an argument declared as _GL_ARG_NONNULL.  */
  20 #define _GL_ARG_NONNULL(params)
  21
  22 #include <config.h>
  23
  24 #include <stdlib.h>
  25
  26 #include "signature.h"
  27 SIGNATURE_CHECK (ptsname_r, int, (int, char *, size_t));
  28
  29 #include <errno.h>
  30 #include <fcntl.h>
  31 #include <signal.h>
  32 #include <stdio.h>
  33 #include <string.h>
  34 #include <unistd.h>
  35 #include <sys/stat.h>
  36
  37 #include "same-inode.h"
  38
  39 #if GNULIB_defined_ptsname_r
  40 # include "null-ptr.h"
  41 #endif
  42
  43 #include "macros.h"
  44
  45 /* Compare two slave names.
  46    On some systems, there are hard links in the /dev/ directory.
  47    For example, on OSF/1 5.1,
  48      /dev/ttyp0 == /dev/pts/0
  49      /dev/ttyp9 == /dev/pts/9
  50      /dev/ttypa == /dev/pts/10
  51      /dev/ttype == /dev/pts/14
  52  */
  53 static int
  54 same_slave (const char *slave_name1, const char *slave_name2)
  55 {
  56   struct stat statbuf1;
  57   struct stat statbuf2;
  58
  59   return (strcmp (slave_name1, slave_name2) == 0
  60           || (stat (slave_name1, &statbuf1) >= 0
  61               && stat (slave_name2, &statbuf2) >= 0
  62               && psame_inode (&statbuf1, &statbuf2)));
  63 }
  64
  65 static void
  66 test_errors (int fd, const char *slave)
  67 {
  68   char buffer[256];
  69   size_t len;
  70   size_t buflen_max;
  71   size_t buflen;
  72   int result;
  73
  74   len = strlen (slave);
  75   buflen_max = len + 5;
  76   if (buflen_max > sizeof buffer)
  77     buflen_max = sizeof buffer;
  78   for (buflen = 0; buflen <= buflen_max; buflen++)
  79     {
  80       memset (buffer, 'X', sizeof buffer);
  81       result = ptsname_r (fd, buffer, buflen);
  82       if (buflen > len)
  83         {
  84           ASSERT (result == 0);
  85           ASSERT (buffer[0] == '/');
  86         }
  87       else
  88         {
  89           ASSERT (result != 0);
  90           ASSERT (result == ERANGE);
  91           ASSERT (buffer[0] == 'X');
  92         }
  93     }
  94
  95   /* This test works only if the ptsname_r implementation comes from gnulib.
  96      If it comes from libc, we have no way to prevent gcc from "optimizing"
  97      the null_ptr function in invalid ways.  See
  98      <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93156>.  */
  99 #if GNULIB_defined_ptsname_r
 100   result = ptsname_r (fd, null_ptr (), 0);
 101   ASSERT (result != 0);
 102   ASSERT (result == EINVAL);
 103 #endif
 104 }
 105
 106 int
 107 main (void)
 108 {
 109 #if HAVE_DECL_ALARM
 110   /* Declare failure if test takes too long, by using default abort
 111      caused by SIGALRM.  */
 112 # if defined _AIX
 113   int alarm_value = 20;
 114 # else
 115   int alarm_value = 5;
 116 # endif
 117   signal (SIGALRM, SIG_DFL);
 118   alarm (alarm_value);
 119 #endif
 120
 121   {
 122     char buffer[256];
 123     int result;
 124
 125     result = ptsname_r (-1, buffer, sizeof buffer);
 126     ASSERT (result != 0);
 127     ASSERT (result == EBADF || result == ENOTTY);
 128   }
 129
 130   {
 131     int fd;
 132     char buffer[256];
 133     int result;
 134
 135     /* Open the controlling tty of the current process.  */
 136     fd = open ("/dev/tty", O_RDONLY);
 137     if (fd < 0)
 138       {
 139         if (test_exit_status != EXIT_SUCCESS)
 140           return test_exit_status;
 141         fprintf (stderr, "Skipping test: cannot open controlling tty\n");
 142         return 77;
 143       }
 144
 145     result = ptsname_r (fd, buffer, sizeof buffer);
 146     /* The result is usually NULL, because /dev/tty is a slave, not a
 147        master.  */
 148     if (result == 0)
 149       {
 150         ASSERT (memcmp (buffer, "/dev/", 5) == 0);
 151       }
 152
 153     close (fd);
 154   }
 155
 156 #if defined __sun || defined __DragonFly__
 157   /* Solaris has BSD-style /dev/pty[p-r][0-9a-f] files, but the function
 158      ptsname() does not work on them.
 159      DragonFly BSD has only /dev/ptmx.  */
 160   {
 161     int fd;
 162     char buffer[256];
 163     int result;
 164
 165     /* Open a pty master.  */
 166     fd = open ("/dev/ptmx", O_RDWR | O_NOCTTY);
 167     if (fd < 0)
 168       {
 169         if (test_exit_status != EXIT_SUCCESS)
 170           return test_exit_status;
 171         fprintf (stderr, "Skipping test: cannot open pseudo-terminal\n");
 172         return 77;
 173       }
 174
 175     result = ptsname_r (fd, buffer, sizeof buffer);
 176     ASSERT (result == 0);
 177     ASSERT (memcmp (buffer, "/dev/pts/", 9) == 0);
 178
 179     test_errors (fd, buffer);
 180
 181     close (fd);
 182   }
 183
 184 #elif defined _AIX
 185   /* AIX has BSD-style /dev/ptyp[0-9a-f] files, and the function ptsname()
 186      produces the corresponding /dev/ttyp[0-9a-f] file for each.  But opening
 187      such a pty causes the process to hang in a state where it does not even
 188      react to the SIGALRM signal for N * 15 seconds, where N is the number of
 189      opened ptys, either in the close (fd) call or - when this close (fd) call
 190      is commented out - at the process exit.
 191      So, better don't use these BSD-style ptys.  The modern way to open a pty
 192      is to go through /dev/ptc.  */
 193   {
 194     int fd;
 195     char buffer[256];
 196     int result;
 197
 198     /* Open a pty master.  */
 199     fd = open ("/dev/ptc", O_RDWR | O_NOCTTY);
 200     if (fd < 0)
 201       {
 202         if (test_exit_status != EXIT_SUCCESS)
 203           return test_exit_status;
 204         fprintf (stderr, "Skipping test: cannot open pseudo-terminal\n");
 205         return 77;
 206       }
 207
 208     result = ptsname_r (fd, buffer, sizeof buffer);
 209     ASSERT (result == 0);
 210     ASSERT (memcmp (buffer, "/dev/pts/", 9) == 0);
 211
 212     test_errors (fd, buffer);
 213
 214     /* This close (fd) call takes 15 seconds.  It would be interruptible by the
 215        SIGALRM timer, but then this test would report failure.  */
 216     close (fd);
 217   }
 218
 219 #elif defined __GNU__ /* Hurd */
 220
 221   /* Try various master names of Hurd: /dev/pty[p-q][0-9a-v]  */
 222   {
 223     int char1;
 224     int char2;
 225
 226     for (char1 = 'p'; char1 <= 'q'; char1++)
 227       for (char2 = '0'; char2 <= 'v'; (char2 == '9' ? char2 = 'a' : char2++))
 228         {
 229           char master_name[32];
 230           int fd;
 231
 232           sprintf (master_name, "/dev/pty%c%c", char1, char2);
 233           fd = open (master_name, O_RDONLY);
 234           if (fd >= 0)
 235             {
 236               char buffer[256];
 237               int result;
 238               char slave_name[32];
 239
 240               result = ptsname_r (fd, buffer, sizeof buffer);
 241               ASSERT (result == 0);
 242               sprintf (slave_name, "/dev/tty%c%c", char1, char2);
 243               ASSERT (same_slave (buffer, slave_name));
 244
 245               test_errors (fd, buffer);
 246
 247               close (fd);
 248             }
 249         }
 250   }
 251
 252 #else
 253
 254   /* Try various master names of Mac OS X: /dev/pty[p-w][0-9a-f]  */
 255   {
 256     int char1;
 257     int char2;
 258
 259     for (char1 = 'p'; char1 <= 'w'; char1++)
 260       for (char2 = '0'; char2 <= 'f'; (char2 == '9' ? char2 = 'a' : char2++))
 261         {
 262           char master_name[32];
 263           int fd;
 264
 265           sprintf (master_name, "/dev/pty%c%c", char1, char2);
 266           fd = open (master_name, O_RDONLY);
 267           if (fd >= 0)
 268             {
 269               char buffer[256];
 270               int result;
 271               char slave_name[32];
 272
 273               result = ptsname_r (fd, buffer, sizeof buffer);
 274               ASSERT (result == 0);
 275               sprintf (slave_name, "/dev/tty%c%c", char1, char2);
 276               ASSERT (same_slave (buffer, slave_name));
 277
 278               test_errors (fd, buffer);
 279
 280               /* This call hangs on AIX.  */
 281               close (fd);
 282             }
 283         }
 284   }
 285
 286   /* Try various master names of *BSD: /dev/pty[p-sP-S][0-9a-v]  */
 287   {
 288     int upper;
 289     int char1;
 290     int char2;
 291
 292     for (upper = 0; upper <= 1; upper++)
 293       for (char1 = (upper ? 'P' : 'p'); char1 <= (upper ? 'S' : 's'); char1++)
 294         for (char2 = '0'; char2 <= 'v'; (char2 == '9' ? char2 = 'a' : char2++))
 295           {
 296             char master_name[32];
 297             int fd;
 298
 299             sprintf (master_name, "/dev/pty%c%c", char1, char2);
 300             fd = open (master_name, O_RDONLY);
 301             if (fd >= 0)
 302               {
 303                 char buffer[256];
 304                 int result;
 305                 char slave_name[32];
 306
 307                 result = ptsname_r (fd, buffer, sizeof buffer);
 308                 ASSERT (result == 0);
 309                 sprintf (slave_name, "/dev/tty%c%c", char1, char2);
 310                 ASSERT (same_slave (buffer, slave_name));
 311
 312                 test_errors (fd, buffer);
 313
 314                 close (fd);
 315               }
 316           }
 317   }
 318
 319 #endif
 320
 321   return test_exit_status;
 322 }