gdb/unittests/scoped_mmap-selftests.c

   1 /* Self tests for scoped_mmap for GDB, the GNU debugger.
   2
   3    Copyright (C) 2018-2023 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 #include "defs.h"
  21
  22 #include "gdbsupport/filestuff.h"
  23 #include "gdbsupport/scoped_mmap.h"
  24 #include "config.h"
  25
  26 #if defined(HAVE_SYS_MMAN_H)
  27
  28 #include "gdbsupport/selftest.h"
  29 #include "gdbsupport/gdb_unlinker.h"
  30
  31 #include <unistd.h>
  32
  33 namespace selftests {
  34 namespace scoped_mmap {
  35
  36 /* Test that the file is unmapped.  */
  37 static void
  38 test_destroy ()
  39 {
  40   void *mem;
  41
  42   errno = 0;
  43   {
  44     ::scoped_mmap smmap (nullptr, sysconf (_SC_PAGESIZE), PROT_WRITE,
  45                          MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
  46
  47     mem = smmap.get ();
  48     SELF_CHECK (mem != nullptr);
  49   }
  50
  51   SELF_CHECK (msync (mem, sysconf (_SC_PAGESIZE), 0) == -1 && errno == ENOMEM);
  52 }
  53
  54 /* Test that the memory can be released.  */
  55 static void
  56 test_release ()
  57 {
  58   void *mem;
  59
  60   errno = 0;
  61   {
  62     ::scoped_mmap smmap (nullptr, sysconf (_SC_PAGESIZE), PROT_WRITE,
  63                          MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
  64
  65     mem = smmap.release ();
  66     SELF_CHECK (mem != nullptr);
  67   }
  68
  69   SELF_CHECK (msync (mem, sysconf (_SC_PAGESIZE), 0) == 0 || errno != ENOMEM);
  70
  71   munmap (mem, sysconf (_SC_PAGESIZE));
  72 }
  73
  74 /* Run selftests.  */
  75 static void
  76 run_tests ()
  77 {
  78   test_destroy ();
  79   test_release ();
  80 }
  81
  82 } /* namespace scoped_mmap */
  83
  84 namespace mmap_file
  85 {
  86
  87 /* Test the standard usage of mmap_file.  */
  88 static void
  89 test_normal ()
  90 {
  91   char filename[] = "scoped_mmapped_file-selftest-XXXXXX";
  92   {
  93     scoped_fd fd = gdb_mkostemp_cloexec (filename);
  94     SELF_CHECK (fd.get () >= 0);
  95
  96     SELF_CHECK (write (fd.get (), "Hello!", 7) == 7);
  97   }
  98
  99   gdb::unlinker unlink_test_file (filename);
 100
 101   {
 102     ::scoped_mmap m = ::mmap_file (filename);
 103
 104     SELF_CHECK (m.get () != MAP_FAILED);
 105     SELF_CHECK (m.size () == 7);
 106     SELF_CHECK (0 == strcmp ((char *) m.get (), "Hello!"));
 107   }
 108 }
 109
 110 /* Calling mmap_file with a non-existent file should throw an exception.  */
 111 static void
 112 test_invalid_filename ()
 113 {
 114   bool threw = false;
 115
 116   try {
 117       ::scoped_mmap m = ::mmap_file ("/this/file/should/not/exist");
 118   } catch (gdb_exception &e) {
 119       threw = true;
 120   }
 121
 122   SELF_CHECK (threw);
 123 }
 124
 125
 126 /* Run selftests.  */
 127 static void
 128 run_tests ()
 129 {
 130   test_normal ();
 131   test_invalid_filename ();
 132 }
 133
 134 } /* namespace mmap_file */
 135 } /* namespace selftests */
 136
 137 #endif /* !defined(HAVE_SYS_MMAN_H) */
 138
 139 void _initialize_scoped_mmap_selftests ();
 140 void
 141 _initialize_scoped_mmap_selftests ()
 142 {
 143 #if defined(HAVE_SYS_MMAN_H)
 144   selftests::register_test ("scoped_mmap",
 145                             selftests::scoped_mmap::run_tests);
 146   selftests::register_test ("mmap_file",
 147                             selftests::mmap_file::run_tests);
 148 #endif
 149 }