gdb/unittests/scoped_mmap-selftests.c

   1 /* Self tests for scoped_mmap for GDB, the GNU debugger.
   2
   3    Copyright (C) 2018-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20
  21 #include "gdbsupport/filestuff.h"
  22 #include "gdbsupport/scoped_mmap.h"
  23 #include "config.h"
  24
  25 #if defined(HAVE_SYS_MMAN_H)
  26
  27 #include "gdbsupport/selftest.h"
  28 #include "gdbsupport/gdb_unlinker.h"
  29
  30 #include <unistd.h>
  31
  32 namespace selftests {
  33 namespace scoped_mmap {
  34
  35 /* Test that the file is unmapped.  */
  36 static void
  37 test_destroy ()
  38 {
  39   void *mem;
  40
  41   errno = 0;
  42   {
  43     ::scoped_mmap smmap (nullptr, sysconf (_SC_PAGESIZE), PROT_WRITE,
  44                          MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
  45
  46     mem = smmap.get ();
  47     SELF_CHECK (mem != nullptr);
  48   }
  49
  50   SELF_CHECK (msync (mem, sysconf (_SC_PAGESIZE), 0) == -1 && errno == ENOMEM);
  51 }
  52
  53 /* Test that the memory can be released.  */
  54 static void
  55 test_release ()
  56 {
  57   void *mem;
  58
  59   errno = 0;
  60   {
  61     ::scoped_mmap smmap (nullptr, sysconf (_SC_PAGESIZE), PROT_WRITE,
  62                          MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
  63
  64     mem = smmap.release ();
  65     SELF_CHECK (mem != nullptr);
  66   }
  67
  68   SELF_CHECK (msync (mem, sysconf (_SC_PAGESIZE), 0) == 0 || errno != ENOMEM);
  69
  70   munmap (mem, sysconf (_SC_PAGESIZE));
  71 }
  72
  73 /* Run selftests.  */
  74 static void
  75 run_tests ()
  76 {
  77   test_destroy ();
  78   test_release ();
  79 }
  80
  81 } /* namespace scoped_mmap */
  82
  83 namespace mmap_file
  84 {
  85
  86 /* Test the standard usage of mmap_file.  */
  87 static void
  88 test_normal ()
  89 {
  90   char filename[] = "scoped_mmapped_file-selftest-XXXXXX";
  91   {
  92     scoped_fd fd = gdb_mkostemp_cloexec (filename);
  93     SELF_CHECK (fd.get () >= 0);
  94
  95     SELF_CHECK (write (fd.get (), "Hello!", 7) == 7);
  96   }
  97
  98   gdb::unlinker unlink_test_file (filename);
  99
 100   {
 101     ::scoped_mmap m = ::mmap_file (filename);
 102
 103     SELF_CHECK (m.get () != MAP_FAILED);
 104     SELF_CHECK (m.size () == 7);
 105     SELF_CHECK (0 == strcmp ((char *) m.get (), "Hello!"));
 106   }
 107 }
 108
 109 /* Calling mmap_file with a non-existent file should throw an exception.  */
 110 static void
 111 test_invalid_filename ()
 112 {
 113   bool threw = false;
 114
 115   try {
 116       ::scoped_mmap m = ::mmap_file ("/this/file/should/not/exist");
 117   } catch (const gdb_exception &e) {
 118       threw = true;
 119   }
 120
 121   SELF_CHECK (threw);
 122 }
 123
 124
 125 /* Run selftests.  */
 126 static void
 127 run_tests ()
 128 {
 129   test_normal ();
 130   test_invalid_filename ();
 131 }
 132
 133 } /* namespace mmap_file */
 134 } /* namespace selftests */
 135
 136 #endif /* !defined(HAVE_SYS_MMAN_H) */
 137
 138 void _initialize_scoped_mmap_selftests ();
 139 void
 140 _initialize_scoped_mmap_selftests ()
 141 {
 142 #if defined(HAVE_SYS_MMAN_H)
 143   selftests::register_test ("scoped_mmap",
 144                             selftests::scoped_mmap::run_tests);
 145   selftests::register_test ("mmap_file",
 146                             selftests::mmap_file::run_tests);
 147 #endif
 148 }