/src/libfsntfs/libcthreads/libcthreads_read_write_lock.c

Source (jump to first uncovered line)
/*
 * Read/Write lock functions
 *
 * Copyright (C) 2012-2024, Joachim Metz <joachim.metz@gmail.com>
 *
 * Refer to AUTHORS for acknowledgements.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <common.h>
#include <memory.h>
#include <types.h>

#include <errno.h>

#if defined( _MSC_VER ) && defined( WINAPI ) && ( WINVER >= 0x0602 )
#include <Synchapi.h>
#endif

#if defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
#include <pthread.h>
#endif

#include "libcthreads_libcerror.h"
#include "libcthreads_read_write_lock.h"
#include "libcthreads_types.h"

#if !defined( HAVE_LOCAL_LIBCTHREADS ) || defined( HAVE_MULTI_THREAD_SUPPORT )

/* Creates a read/write lock
 * Make sure the value read_write_lock is referencing, is set to NULL
 * Returns 1 if successful or -1 on error
 */
int libcthreads_read_write_lock_initialize(
     libcthreads_read_write_lock_t **read_write_lock,
     libcerror_error_t **error )
{
  libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
  static char *function                                            = "libcthreads_read_write_lock_initialize";

#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
  DWORD error_code                                                 = 0;

#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
  int pthread_result                                               = 0;
#endif

  if( read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid read/write lock.",
     function );

    return( -1 );
  }
  if( *read_write_lock != NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,
     "%s: invalid read/write lock value already set.",
     function );

    return( -1 );
  }
  internal_read_write_lock = memory_allocate_structure(
                              libcthreads_internal_read_write_lock_t );

  if( internal_read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
     "%s: unable to create read/write lock.",
     function );

    goto on_error;
  }
  if( memory_set(
       internal_read_write_lock,
       0,
       sizeof( libcthreads_internal_read_write_lock_t ) ) == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_SET_FAILED,
     "%s: unable to clear read/write lock.",
     function );

    memory_free(
     internal_read_write_lock );

    return( -1 );
  }
#if defined( WINAPI ) && ( WINVER >= 0x0600 )
  InitializeSRWLock(
   &( internal_read_write_lock->slim_read_write_lock ) );

#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
  InitializeCriticalSection(
   &( internal_read_write_lock->write_critical_section ) );

  InitializeCriticalSection(
   &( internal_read_write_lock->read_critical_section ) );

  internal_read_write_lock->no_read_event_handle = CreateEvent(
                                                    NULL,
                                                    TRUE,
                                                    TRUE,
                                                    NULL );

  if( internal_read_write_lock->no_read_event_handle == NULL )
  {
    error_code = GetLastError();

    libcerror_system_set_error(
     error,
     error_code,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_INITIALIZE_FAILED,
     "%s: unable to initialize no read event handle.",
     function );

    goto on_error;
  }
#elif defined( WINAPI )

#error libcthreads_read_write_lock_initialize for Windows earlier than NT4 not implemented

#elif defined( HAVE_PTHREAD_H )
  pthread_result = pthread_rwlock_init(
                    &( internal_read_write_lock->read_write_lock ),
                    NULL );

  switch( pthread_result )
  {
    case 0:
      break;

    case EAGAIN:
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to initialize read/write lock with error: Insufficient resources.",
       function );

      goto on_error;

    default:
      libcerror_system_set_error(
       error,
       pthread_result,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to initialize read/write lock.",
       function );

      goto on_error;
  }
#endif
  *read_write_lock = (libcthreads_read_write_lock_t *) internal_read_write_lock;

  return( 1 );

on_error:
  if( internal_read_write_lock != NULL )
  {
#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
    DeleteCriticalSection(
     &( internal_read_write_lock->read_critical_section ) );

    DeleteCriticalSection(
     &( internal_read_write_lock->write_critical_section ) );
#endif
    memory_free(
     internal_read_write_lock );
  }
  return( -1 );
}

/* Frees a read/write lock
 * Returns 1 if successful or -1 on error
 */
int libcthreads_read_write_lock_free(
     libcthreads_read_write_lock_t **read_write_lock,
     libcerror_error_t **error )
{
  libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
  static char *function                                            = "libcthreads_read_write_lock_free";
  int result                                                       = 1;

#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
  DWORD error_code                                                 = 0;

#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
  int pthread_result                                               = 0;
#endif

  if( read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid read/write lock.",
     function );

    return( -1 );
  }
  if( *read_write_lock != NULL )
  {
    internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) *read_write_lock;
    *read_write_lock         = NULL;

#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
    if( CloseHandle(
         internal_read_write_lock->no_read_event_handle ) == 0 )
    {
      error_code = GetLastError();

      libcerror_system_set_error(
       error,
       error_code,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to free no read event handle.",
       function );

      result = -1;
    }
    DeleteCriticalSection(
     &( internal_read_write_lock->read_critical_section ) );

    DeleteCriticalSection(
     &( internal_read_write_lock->write_critical_section ) );

#elif defined( WINAPI ) && ( WINVER < 0x0400 )

#error libcthreads_read_write_lock_free for Windows earlier than NT4 not implemented

#elif defined( HAVE_PTHREAD_H )
    pthread_result = pthread_rwlock_destroy(
                      &( internal_read_write_lock->read_write_lock ) );

    switch( pthread_result )
    {
      case 0:
        break;

      case EAGAIN:
        libcerror_error_set(
         error,
         LIBCERROR_ERROR_DOMAIN_RUNTIME,
         LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
         "%s: unable to destroy read/write lock with error: Insufficient resources.",
         function );

        result = -1;
        break;

      case EBUSY:
        libcerror_error_set(
         error,
         LIBCERROR_ERROR_DOMAIN_RUNTIME,
         LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
         "%s: unable to destroy read/write lock with error: Resource busy.",
         function );

        result = -1;
        break;

      default:
        libcerror_system_set_error(
         error,
         pthread_result,
         LIBCERROR_ERROR_DOMAIN_RUNTIME,
         LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
         "%s: unable to destroy read/write lock.",
         function );

        result = -1;
        break;
    }
#endif
    memory_free(
     internal_read_write_lock );
  }
  return( result );
}

/* Grabs a read/write lock for reading
 * Returns 1 if successful or -1 on error
 */
int libcthreads_read_write_lock_grab_for_read(
     libcthreads_read_write_lock_t *read_write_lock,
     libcerror_error_t **error )
{
  libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
  static char *function                                            = "libcthreads_read_write_lock_grab_for_read";

#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
  DWORD error_code                                                 = 0;
  BOOL result                                                      = 0;

#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
  int pthread_result                                               = 0;
#endif

  if( read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid read/write lock.",
     function );

    return( -1 );
  }
  internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;

#if defined( WINAPI ) && ( WINVER >= 0x0600 )
  AcquireSRWLockShared(
   &( internal_read_write_lock->slim_read_write_lock ) );

#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
  EnterCriticalSection(
   &( internal_read_write_lock->write_critical_section ) );

  EnterCriticalSection(
   &( internal_read_write_lock->read_critical_section ) );

  internal_read_write_lock->number_of_readers++;

  if( internal_read_write_lock->number_of_readers == 1 )
  {
    result = ResetEvent(
              internal_read_write_lock->no_read_event_handle );

    if( result == 0 )
    {
      error_code = GetLastError();

      internal_read_write_lock->number_of_readers--;
    }
  }
  else
  {
    result = 1;
  }
  LeaveCriticalSection(
   &( internal_read_write_lock->read_critical_section ) );

  LeaveCriticalSection(
   &( internal_read_write_lock->write_critical_section ) );

  if( result == 0 )
  {
    libcerror_system_set_error(
     error,
     error_code,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_SET_FAILED,
     "%s: reset of no read event failed.",
     function );

    return( -1 );
  }
#elif defined( WINAPI )

#error libcthreads_read_write_lock_grab_for_read for Windows earlier than NT4 not implemented

#elif defined( HAVE_PTHREAD_H )
  pthread_result = pthread_rwlock_rdlock(
                    &( internal_read_write_lock->read_write_lock ) );

  switch( pthread_result )
  {
    case 0:
      break;

    case EAGAIN:
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to lock read/write lock for read with error: Maximum number of locks exceeded.",
       function );

      return( -1 );

    case EDEADLK:
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to lock read/write lock for read with error: Deadlock condition detected.",
       function );

      return( -1 );

    default:
      libcerror_system_set_error(
       error,
       pthread_result,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to lock read/write lock for read.",
       function );

      return( -1 );
  }
#endif
  return( 1 );
}

/* Grabs a read/write lock for writing
 * Returns 1 if successful or -1 on error
 */
int libcthreads_read_write_lock_grab_for_write(
     libcthreads_read_write_lock_t *read_write_lock,
     libcerror_error_t **error )
{
  libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
  static char *function                                            = "libcthreads_read_write_lock_grab_for_write";

#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
  DWORD error_code                                                 = 0;
  DWORD wait_status                                                = 0;

#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
  int pthread_result                                               = 0;
#endif

  if( read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid read/write lock.",
     function );

    return( -1 );
  }
  internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;

#if defined( WINAPI ) && ( WINVER >= 0x0600 )
  AcquireSRWLockExclusive(
   &( internal_read_write_lock->slim_read_write_lock ) );

#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
  EnterCriticalSection(
   &( internal_read_write_lock->write_critical_section ) );

  wait_status = WaitForSingleObject(
                 internal_read_write_lock->no_read_event_handle,
                 INFINITE );

  if( wait_status == WAIT_FAILED )
  {
    error_code = GetLastError();

    LeaveCriticalSection(
     &( internal_read_write_lock->write_critical_section ) );

    libcerror_system_set_error(
     error,
     error_code,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
     "%s: wait for no read event handle failed.",
     function );

    return( -1 );
  }
#elif defined( WINAPI )

#error libcthreads_read_write_lock_grab_for_write for Windows earlier than NT4 not implemented

#elif defined( HAVE_PTHREAD_H )
  pthread_result = pthread_rwlock_wrlock(
                    &( internal_read_write_lock->read_write_lock ) );

  switch( pthread_result )
  {
    case 0:
      break;

    case EDEADLK:
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to lock read/write lock for write with error: Deadlock condition detected.",
       function );

      return( -1 );

    default:
      libcerror_system_set_error(
       error,
       pthread_result,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
       "%s: unable to lock read/write lock for write.",
       function );

      return( -1 );
  }
#endif
  return( 1 );
}

/* Releases a read/write lock for reading
 * Returns 1 if successful or -1 on error
 */
int libcthreads_read_write_lock_release_for_read(
     libcthreads_read_write_lock_t *read_write_lock,
     libcerror_error_t **error )
{
  libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
  static char *function                                            = "libcthreads_read_write_lock_release_for_read";

#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
  DWORD error_code                                                 = 0;
  BOOL result                                                      = 0;

#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
  int pthread_result                                               = 0;
#endif

  if( read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid read/write lock.",
     function );

    return( -1 );
  }
  internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;

#if defined( WINAPI ) && ( WINVER >= 0x0600 )
  ReleaseSRWLockShared(
   &( internal_read_write_lock->slim_read_write_lock ) );

#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
  EnterCriticalSection(
   &( internal_read_write_lock->read_critical_section ) );

  internal_read_write_lock->number_of_readers--;

  if( internal_read_write_lock->number_of_readers == 0 )
  {
    result = SetEvent(
              internal_read_write_lock->no_read_event_handle );

    if( result == 0 )
    {
      error_code = GetLastError();

      internal_read_write_lock->number_of_readers++;
    }
  }
  else
  {
    result = 1;
  }
  LeaveCriticalSection(
   &( internal_read_write_lock->read_critical_section ) );

  if( result == 0 )
  {
    libcerror_system_set_error(
     error,
     error_code,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_SET_FAILED,
     "%s: set of no read event failed.",
     function );

    return( -1 );
  }
#elif defined( WINAPI )

#error libcthreads_read_write_lock_release_for_read for Windows earlier than NT4 not implemented

#elif defined( HAVE_PTHREAD_H )
  pthread_result = pthread_rwlock_unlock(
                    &( internal_read_write_lock->read_write_lock ) );

  if( pthread_result != 0 )
  {
    libcerror_system_set_error(
     error,
     pthread_result,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_SET_FAILED,
     "%s: unable to unlock read/write lock.",
     function );

    return( -1 );
  }
#endif
  return( 1 );
}

/* Releases a read/write lock for writing
 * Returns 1 if successful or -1 on error
 */
int libcthreads_read_write_lock_release_for_write(
     libcthreads_read_write_lock_t *read_write_lock,
     libcerror_error_t **error )
{
  libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
  static char *function                                            = "libcthreads_read_write_lock_release_for_write";

#if defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
  int pthread_result                                               = 0;
#endif

  if( read_write_lock == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid read/write lock.",
     function );

    return( -1 );
  }
  internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;

#if defined( WINAPI ) && ( WINVER >= 0x0600 )
  ReleaseSRWLockExclusive(
   &( internal_read_write_lock->slim_read_write_lock ) );

#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
  LeaveCriticalSection(
   &( internal_read_write_lock->write_critical_section ) );

#elif defined( WINAPI )

#error libcthreads_read_write_lock_release_for_write for Windows earlier than NT4 not implemented

#elif defined( HAVE_PTHREAD_H )
  pthread_result = pthread_rwlock_unlock(
                    &( internal_read_write_lock->read_write_lock ) );

  if( pthread_result != 0 )
  {
    libcerror_system_set_error(
     error,
     pthread_result,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_SET_FAILED,
     "%s: unable to unlock read/write lock.",
     function );

    return( -1 );
  }
#endif
  return( 1 );
}

#endif /* !defined( HAVE_LOCAL_LIBCTHREADS ) || defined( HAVE_MULTI_THREAD_SUPPORT ) */


Coverage Report

Created: 2024-02-25 07:20

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Read/Write lock functions
3		*
4		* Copyright (C) 2012-2024, Joachim Metz <joachim.metz@gmail.com>
5		*
6		* Refer to AUTHORS for acknowledgements.
7		*
8		* This program is free software: you can redistribute it and/or modify
9		* it under the terms of the GNU Lesser General Public License as published by
10		* the Free Software Foundation, either version 3 of the License, or
11		* (at your option) any later version.
12		*
13		* This program is distributed in the hope that it will be useful,
14		* but WITHOUT ANY WARRANTY; without even the implied warranty of
15		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16		* GNU General Public License for more details.
17		*
18		* You should have received a copy of the GNU Lesser General Public License
19		* along with this program. If not, see <https://www.gnu.org/licenses/>.
20		*/
21
22		#include <common.h>
23		#include <memory.h>
24		#include <types.h>
25
26		#include <errno.h>
27
28		#if defined( _MSC_VER ) && defined( WINAPI ) && ( WINVER >= 0x0602 )
29		#include <Synchapi.h>
30		#endif
31
32		#if defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
33		#include <pthread.h>
34		#endif
35
36		#include "libcthreads_libcerror.h"
37		#include "libcthreads_read_write_lock.h"
38		#include "libcthreads_types.h"
39
40		#if !defined( HAVE_LOCAL_LIBCTHREADS ) \|\| defined( HAVE_MULTI_THREAD_SUPPORT )
41
42		/* Creates a read/write lock
43		* Make sure the value read_write_lock is referencing, is set to NULL
44		* Returns 1 if successful or -1 on error
45		*/
46		int libcthreads_read_write_lock_initialize(
47		libcthreads_read_write_lock_t **read_write_lock,
48		libcerror_error_t **error )
49	129k	{
50	129k	libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
51	129k	static char *function = "libcthreads_read_write_lock_initialize";
52
53		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
54		DWORD error_code = 0;
55
56		#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
57	129k	int pthread_result = 0;
58	129k	#endif
59
60	129k	if( read_write_lock == NULL )
61	0	{
62	0	libcerror_error_set(
63	0	error,
64	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
65	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
66	0	"%s: invalid read/write lock.",
67	0	function );
68
69	0	return( -1 );
70	0	}
71	129k	if( *read_write_lock != NULL )
72	0	{
73	0	libcerror_error_set(
74	0	error,
75	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
76	0	LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,
77	0	"%s: invalid read/write lock value already set.",
78	0	function );
79
80	0	return( -1 );
81	0	}
82	129k	internal_read_write_lock = memory_allocate_structure(
83	129k	libcthreads_internal_read_write_lock_t );
84
85	129k	if( internal_read_write_lock == NULL )
86	0	{
87	0	libcerror_error_set(
88	0	error,
89	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
90	0	LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
91	0	"%s: unable to create read/write lock.",
92	0	function );
93
94	0	goto on_error;
95	0	}
96	129k	if( memory_set(
97	129k	internal_read_write_lock,
98	129k	0,
99	129k	sizeof( libcthreads_internal_read_write_lock_t ) ) == NULL )
100	0	{
101	0	libcerror_error_set(
102	0	error,
103	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
104	0	LIBCERROR_MEMORY_ERROR_SET_FAILED,
105	0	"%s: unable to clear read/write lock.",
106	0	function );
107
108	0	memory_free(
109	0	internal_read_write_lock );
110
111	0	return( -1 );
112	0	}
113		#if defined( WINAPI ) && ( WINVER >= 0x0600 )
114		InitializeSRWLock(
115		&( internal_read_write_lock->slim_read_write_lock ) );
116
117		#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
118		InitializeCriticalSection(
119		&( internal_read_write_lock->write_critical_section ) );
120
121		InitializeCriticalSection(
122		&( internal_read_write_lock->read_critical_section ) );
123
124		internal_read_write_lock->no_read_event_handle = CreateEvent(
125		NULL,
126		TRUE,
127		TRUE,
128		NULL );
129
130		if( internal_read_write_lock->no_read_event_handle == NULL )
131		{
132		error_code = GetLastError();
133
134		libcerror_system_set_error(
135		error,
136		error_code,
137		LIBCERROR_ERROR_DOMAIN_RUNTIME,
138		LIBCERROR_RUNTIME_ERROR_INITIALIZE_FAILED,
139		"%s: unable to initialize no read event handle.",
140		function );
141
142		goto on_error;
143		}
144		#elif defined( WINAPI )
145
146		#error libcthreads_read_write_lock_initialize for Windows earlier than NT4 not implemented
147
148		#elif defined( HAVE_PTHREAD_H )
149	129k	pthread_result = pthread_rwlock_init(
150	129k	&( internal_read_write_lock->read_write_lock ),
151	129k	NULL );
152
153	129k	switch( pthread_result )
154	129k	{
155	129k	case 0:
156	129k	break;
157
158	0	case EAGAIN:
159	0	libcerror_error_set(
160	0	error,
161	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
162	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
163	0	"%s: unable to initialize read/write lock with error: Insufficient resources.",
164	0	function );
165
166	0	goto on_error;
167
168	0	default:
169	0	libcerror_system_set_error(
170	0	error,
171	0	pthread_result,
172	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
173	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
174	0	"%s: unable to initialize read/write lock.",
175	0	function );
176
177	0	goto on_error;
178	129k	}
179	129k	#endif
180	129k	read_write_lock = (libcthreads_read_write_lock_t ) internal_read_write_lock;
181
182	129k	return( 1 );
183
184	0	on_error:
185	0	if( internal_read_write_lock != NULL )
186	0	{
187		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
188		DeleteCriticalSection(
189		&( internal_read_write_lock->read_critical_section ) );
190
191		DeleteCriticalSection(
192		&( internal_read_write_lock->write_critical_section ) );
193		#endif
194	0	memory_free(
195	0	internal_read_write_lock );
196	0	}
197	0	return( -1 );
198	129k	}
199
200		/* Frees a read/write lock
201		* Returns 1 if successful or -1 on error
202		*/
203		int libcthreads_read_write_lock_free(
204		libcthreads_read_write_lock_t **read_write_lock,
205		libcerror_error_t **error )
206	129k	{
207	129k	libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
208	129k	static char *function = "libcthreads_read_write_lock_free";
209	129k	int result = 1;
210
211		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
212		DWORD error_code = 0;
213
214		#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
215	129k	int pthread_result = 0;
216	129k	#endif
217
218	129k	if( read_write_lock == NULL )
219	0	{
220	0	libcerror_error_set(
221	0	error,
222	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
223	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
224	0	"%s: invalid read/write lock.",
225	0	function );
226
227	0	return( -1 );
228	0	}
229	129k	if( *read_write_lock != NULL )
230	129k	{
231	129k	internal_read_write_lock = (libcthreads_internal_read_write_lock_t ) read_write_lock;
232	129k	*read_write_lock = NULL;
233
234		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
235		if( CloseHandle(
236		internal_read_write_lock->no_read_event_handle ) == 0 )
237		{
238		error_code = GetLastError();
239
240		libcerror_system_set_error(
241		error,
242		error_code,
243		LIBCERROR_ERROR_DOMAIN_RUNTIME,
244		LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
245		"%s: unable to free no read event handle.",
246		function );
247
248		result = -1;
249		}
250		DeleteCriticalSection(
251		&( internal_read_write_lock->read_critical_section ) );
252
253		DeleteCriticalSection(
254		&( internal_read_write_lock->write_critical_section ) );
255
256		#elif defined( WINAPI ) && ( WINVER < 0x0400 )
257
258		#error libcthreads_read_write_lock_free for Windows earlier than NT4 not implemented
259
260		#elif defined( HAVE_PTHREAD_H )
261	129k	pthread_result = pthread_rwlock_destroy(
262	129k	&( internal_read_write_lock->read_write_lock ) );
263
264	129k	switch( pthread_result )
265	129k	{
266	129k	case 0:
267	129k	break;
268
269	0	case EAGAIN:
270	0	libcerror_error_set(
271	0	error,
272	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
273	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
274	0	"%s: unable to destroy read/write lock with error: Insufficient resources.",
275	0	function );
276
277	0	result = -1;
278	0	break;
279
280	0	case EBUSY:
281	0	libcerror_error_set(
282	0	error,
283	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
284	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
285	0	"%s: unable to destroy read/write lock with error: Resource busy.",
286	0	function );
287
288	0	result = -1;
289	0	break;
290
291	0	default:
292	0	libcerror_system_set_error(
293	0	error,
294	0	pthread_result,
295	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
296	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
297	0	"%s: unable to destroy read/write lock.",
298	0	function );
299
300	0	result = -1;
301	0	break;
302	129k	}
303	129k	#endif
304	129k	memory_free(
305	129k	internal_read_write_lock );
306	129k	}
307	129k	return( result );
308	129k	}
309
310		/* Grabs a read/write lock for reading
311		* Returns 1 if successful or -1 on error
312		*/
313		int libcthreads_read_write_lock_grab_for_read(
314		libcthreads_read_write_lock_t *read_write_lock,
315		libcerror_error_t **error )
316	65.6k	{
317	65.6k	libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
318	65.6k	static char *function = "libcthreads_read_write_lock_grab_for_read";
319
320		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
321		DWORD error_code = 0;
322		BOOL result = 0;
323
324		#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
325	65.6k	int pthread_result = 0;
326	65.6k	#endif
327
328	65.6k	if( read_write_lock == NULL )
329	0	{
330	0	libcerror_error_set(
331	0	error,
332	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
333	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
334	0	"%s: invalid read/write lock.",
335	0	function );
336
337	0	return( -1 );
338	0	}
339	65.6k	internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;
340
341		#if defined( WINAPI ) && ( WINVER >= 0x0600 )
342		AcquireSRWLockShared(
343		&( internal_read_write_lock->slim_read_write_lock ) );
344
345		#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
346		EnterCriticalSection(
347		&( internal_read_write_lock->write_critical_section ) );
348
349		EnterCriticalSection(
350		&( internal_read_write_lock->read_critical_section ) );
351
352		internal_read_write_lock->number_of_readers++;
353
354		if( internal_read_write_lock->number_of_readers == 1 )
355		{
356		result = ResetEvent(
357		internal_read_write_lock->no_read_event_handle );
358
359		if( result == 0 )
360		{
361		error_code = GetLastError();
362
363		internal_read_write_lock->number_of_readers--;
364		}
365		}
366		else
367		{
368		result = 1;
369		}
370		LeaveCriticalSection(
371		&( internal_read_write_lock->read_critical_section ) );
372
373		LeaveCriticalSection(
374		&( internal_read_write_lock->write_critical_section ) );
375
376		if( result == 0 )
377		{
378		libcerror_system_set_error(
379		error,
380		error_code,
381		LIBCERROR_ERROR_DOMAIN_RUNTIME,
382		LIBCERROR_RUNTIME_ERROR_SET_FAILED,
383		"%s: reset of no read event failed.",
384		function );
385
386		return( -1 );
387		}
388		#elif defined( WINAPI )
389
390		#error libcthreads_read_write_lock_grab_for_read for Windows earlier than NT4 not implemented
391
392		#elif defined( HAVE_PTHREAD_H )
393	65.6k	pthread_result = pthread_rwlock_rdlock(
394	65.6k	&( internal_read_write_lock->read_write_lock ) );
395
396	65.6k	switch( pthread_result )
397	65.6k	{
398	65.6k	case 0:
399	65.6k	break;
400
401	0	case EAGAIN:
402	0	libcerror_error_set(
403	0	error,
404	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
405	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
406	0	"%s: unable to lock read/write lock for read with error: Maximum number of locks exceeded.",
407	0	function );
408
409	0	return( -1 );
410
411	0	case EDEADLK:
412	0	libcerror_error_set(
413	0	error,
414	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
415	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
416	0	"%s: unable to lock read/write lock for read with error: Deadlock condition detected.",
417	0	function );
418
419	0	return( -1 );
420
421	0	default:
422	0	libcerror_system_set_error(
423	0	error,
424	0	pthread_result,
425	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
426	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
427	0	"%s: unable to lock read/write lock for read.",
428	0	function );
429
430	0	return( -1 );
431	65.6k	}
432	65.6k	#endif
433	65.6k	return( 1 );
434	65.6k	}
435
436		/* Grabs a read/write lock for writing
437		* Returns 1 if successful or -1 on error
438		*/
439		int libcthreads_read_write_lock_grab_for_write(
440		libcthreads_read_write_lock_t *read_write_lock,
441		libcerror_error_t **error )
442	142k	{
443	142k	libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
444	142k	static char *function = "libcthreads_read_write_lock_grab_for_write";
445
446		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
447		DWORD error_code = 0;
448		DWORD wait_status = 0;
449
450		#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
451	142k	int pthread_result = 0;
452	142k	#endif
453
454	142k	if( read_write_lock == NULL )
455	0	{
456	0	libcerror_error_set(
457	0	error,
458	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
459	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
460	0	"%s: invalid read/write lock.",
461	0	function );
462
463	0	return( -1 );
464	0	}
465	142k	internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;
466
467		#if defined( WINAPI ) && ( WINVER >= 0x0600 )
468		AcquireSRWLockExclusive(
469		&( internal_read_write_lock->slim_read_write_lock ) );
470
471		#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
472		EnterCriticalSection(
473		&( internal_read_write_lock->write_critical_section ) );
474
475		wait_status = WaitForSingleObject(
476		internal_read_write_lock->no_read_event_handle,
477		INFINITE );
478
479		if( wait_status == WAIT_FAILED )
480		{
481		error_code = GetLastError();
482
483		LeaveCriticalSection(
484		&( internal_read_write_lock->write_critical_section ) );
485
486		libcerror_system_set_error(
487		error,
488		error_code,
489		LIBCERROR_ERROR_DOMAIN_RUNTIME,
490		LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
491		"%s: wait for no read event handle failed.",
492		function );
493
494		return( -1 );
495		}
496		#elif defined( WINAPI )
497
498		#error libcthreads_read_write_lock_grab_for_write for Windows earlier than NT4 not implemented
499
500		#elif defined( HAVE_PTHREAD_H )
501	142k	pthread_result = pthread_rwlock_wrlock(
502	142k	&( internal_read_write_lock->read_write_lock ) );
503
504	142k	switch( pthread_result )
505	142k	{
506	142k	case 0:
507	142k	break;
508
509	0	case EDEADLK:
510	0	libcerror_error_set(
511	0	error,
512	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
513	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
514	0	"%s: unable to lock read/write lock for write with error: Deadlock condition detected.",
515	0	function );
516
517	0	return( -1 );
518
519	0	default:
520	0	libcerror_system_set_error(
521	0	error,
522	0	pthread_result,
523	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
524	0	LIBCERROR_RUNTIME_ERROR_FINALIZE_FAILED,
525	0	"%s: unable to lock read/write lock for write.",
526	0	function );
527
528	0	return( -1 );
529	142k	}
530	142k	#endif
531	142k	return( 1 );
532	142k	}
533
534		/* Releases a read/write lock for reading
535		* Returns 1 if successful or -1 on error
536		*/
537		int libcthreads_read_write_lock_release_for_read(
538		libcthreads_read_write_lock_t *read_write_lock,
539		libcerror_error_t **error )
540	65.6k	{
541	65.6k	libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
542	65.6k	static char *function = "libcthreads_read_write_lock_release_for_read";
543
544		#if defined( WINAPI ) && ( WINVER >= 0x0400 ) && ( WINVER < 0x0600 )
545		DWORD error_code = 0;
546		BOOL result = 0;
547
548		#elif defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
549	65.6k	int pthread_result = 0;
550	65.6k	#endif
551
552	65.6k	if( read_write_lock == NULL )
553	0	{
554	0	libcerror_error_set(
555	0	error,
556	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
557	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
558	0	"%s: invalid read/write lock.",
559	0	function );
560
561	0	return( -1 );
562	0	}
563	65.6k	internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;
564
565		#if defined( WINAPI ) && ( WINVER >= 0x0600 )
566		ReleaseSRWLockShared(
567		&( internal_read_write_lock->slim_read_write_lock ) );
568
569		#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
570		EnterCriticalSection(
571		&( internal_read_write_lock->read_critical_section ) );
572
573		internal_read_write_lock->number_of_readers--;
574
575		if( internal_read_write_lock->number_of_readers == 0 )
576		{
577		result = SetEvent(
578		internal_read_write_lock->no_read_event_handle );
579
580		if( result == 0 )
581		{
582		error_code = GetLastError();
583
584		internal_read_write_lock->number_of_readers++;
585		}
586		}
587		else
588		{
589		result = 1;
590		}
591		LeaveCriticalSection(
592		&( internal_read_write_lock->read_critical_section ) );
593
594		if( result == 0 )
595		{
596		libcerror_system_set_error(
597		error,
598		error_code,
599		LIBCERROR_ERROR_DOMAIN_RUNTIME,
600		LIBCERROR_RUNTIME_ERROR_SET_FAILED,
601		"%s: set of no read event failed.",
602		function );
603
604		return( -1 );
605		}
606		#elif defined( WINAPI )
607
608		#error libcthreads_read_write_lock_release_for_read for Windows earlier than NT4 not implemented
609
610		#elif defined( HAVE_PTHREAD_H )
611	65.6k	pthread_result = pthread_rwlock_unlock(
612	65.6k	&( internal_read_write_lock->read_write_lock ) );
613
614	65.6k	if( pthread_result != 0 )
615	0	{
616	0	libcerror_system_set_error(
617	0	error,
618	0	pthread_result,
619	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
620	0	LIBCERROR_RUNTIME_ERROR_SET_FAILED,
621	0	"%s: unable to unlock read/write lock.",
622	0	function );
623
624	0	return( -1 );
625	0	}
626	65.6k	#endif
627	65.6k	return( 1 );
628	65.6k	}
629
630		/* Releases a read/write lock for writing
631		* Returns 1 if successful or -1 on error
632		*/
633		int libcthreads_read_write_lock_release_for_write(
634		libcthreads_read_write_lock_t *read_write_lock,
635		libcerror_error_t **error )
636	142k	{
637	142k	libcthreads_internal_read_write_lock_t *internal_read_write_lock = NULL;
638	142k	static char *function = "libcthreads_read_write_lock_release_for_write";
639
640	142k	#if defined( HAVE_PTHREAD_H ) && !defined( WINAPI )
641	142k	int pthread_result = 0;
642	142k	#endif
643
644	142k	if( read_write_lock == NULL )
645	0	{
646	0	libcerror_error_set(
647	0	error,
648	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
649	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
650	0	"%s: invalid read/write lock.",
651	0	function );
652
653	0	return( -1 );
654	0	}
655	142k	internal_read_write_lock = (libcthreads_internal_read_write_lock_t *) read_write_lock;
656
657		#if defined( WINAPI ) && ( WINVER >= 0x0600 )
658		ReleaseSRWLockExclusive(
659		&( internal_read_write_lock->slim_read_write_lock ) );
660
661		#elif defined( WINAPI ) && ( WINVER >= 0x0400 )
662		LeaveCriticalSection(
663		&( internal_read_write_lock->write_critical_section ) );
664
665		#elif defined( WINAPI )
666
667		#error libcthreads_read_write_lock_release_for_write for Windows earlier than NT4 not implemented
668
669		#elif defined( HAVE_PTHREAD_H )
670	142k	pthread_result = pthread_rwlock_unlock(
671	142k	&( internal_read_write_lock->read_write_lock ) );
672
673	142k	if( pthread_result != 0 )
674	0	{
675	0	libcerror_system_set_error(
676	0	error,
677	0	pthread_result,
678	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
679	0	LIBCERROR_RUNTIME_ERROR_SET_FAILED,
680	0	"%s: unable to unlock read/write lock.",
681	0	function );
682
683	0	return( -1 );
684	0	}
685	142k	#endif
686	142k	return( 1 );
687	142k	}
688
689		#endif /* !defined( HAVE_LOCAL_LIBCTHREADS ) \|\| defined( HAVE_MULTI_THREAD_SUPPORT ) */
690