Fix a bug about the iSCSI DHCP dependency issue.

[mirror_edk2.git] / StdLib / LibC / Stdio / flockfile.c

/*  $NetBSD: flockfile.c,v 1.8 2003/07/22 00:56:25 nathanw Exp $  */\r
\r
/*-\r
 * Copyright (c) 2002 The NetBSD Foundation, Inc.\r
 * All rights reserved.\r
 *\r
 * This code is derived from software contributed to The NetBSD Foundation\r
 * by Nathan J. Williams.\r
 *\r
 * Redistribution and use in source and binary forms, with or without\r
 * modification, are permitted provided that the following conditions\r
 * are met:\r
 * 1. Redistributions of source code must retain the above copyright\r
 *    notice, this list of conditions and the following disclaimer.\r
 * 2. Redistributions in binary form must reproduce the above copyright\r
 *    notice, this list of conditions and the following disclaimer in the\r
 *    documentation and/or other materials provided with the distribution.\r
 * 3. All advertising materials mentioning features or use of this software\r
 *    must display the following acknowledgement:\r
 *        This product includes software developed by the NetBSD\r
 *        Foundation, Inc. and its contributors.\r
 * 4. Neither the name of The NetBSD Foundation nor the names of its\r
 *    contributors may be used to endorse or promote products derived\r
 *    from this software without specific prior written permission.\r
 *\r
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS\r
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED\r
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR\r
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS\r
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR\r
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF\r
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS\r
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN\r
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)\r
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\r
 * POSSIBILITY OF SUCH DAMAGE.\r
 */\r
#include  <LibConfig.h>\r
#include <sys/EfiCdefs.h>\r
#if defined(LIBC_SCCS) && !defined(lint)\r
__RCSID("$NetBSD: flockfile.c,v 1.8 2003/07/22 00:56:25 nathanw Exp $");\r
#endif /* LIBC_SCCS and not lint */\r
\r
#include "namespace.h"\r
\r
#include <assert.h>\r
#include <errno.h>\r
#include <stdio.h>\r
#include <string.h>\r
#include "reentrant.h"\r
#include "local.h"\r
\r
#ifdef __weak_alias\r
__weak_alias(flockfile,_flockfile)\r
__weak_alias(ftrylockfile,_ftrylockfile)\r
__weak_alias(funlockfile,_funlockfile)\r
#endif\r
\r
#ifdef _REENTRANT\r
/*\r
 * XXX This code makes the assumption that a thr_t (pthread_t) is a\r
 * XXX pointer.\r
 */\r
\r
extern int __isthreaded;\r
\r
void\r
flockfile(FILE *fp)\r
{\r
\r
  __flockfile_internal(fp, 0);\r
}\r
\r
int\r
ftrylockfile(FILE *fp)\r
{\r
  int retval;\r
\r
  if (__isthreaded == 0)\r
    return 0;\r
\r
  retval = 0;\r
  mutex_lock(&_LOCK(fp));\r
\r
  if (_LOCKOWNER(fp) == thr_self()) {\r
    _LOCKCOUNT(fp)++;\r
  } else if (_LOCKOWNER(fp) == NULL) {\r
    _LOCKOWNER(fp) = thr_self();\r
    _LOCKCOUNT(fp) = 1;\r
  } else\r
    retval = -1;\r
\r
  mutex_unlock(&_LOCK(fp));\r
\r
  return retval;\r
}\r
\r
void\r
funlockfile(FILE *fp)\r
{\r
\r
  __funlockfile_internal(fp, 0);\r
}\r
\r
void\r
__flockfile_internal(FILE *fp, int internal)\r
{\r
\r
  if (__isthreaded == 0)\r
    return;\r
\r
  mutex_lock(&_LOCK(fp));\r
\r
  if (_LOCKOWNER(fp) == thr_self()) {\r
    _LOCKCOUNT(fp)++;\r
    if (internal)\r
      _LOCKINTERNAL(fp)++;\r
  } else {\r
    /* danger! cond_wait() is a cancellation point. */\r
    int oldstate;\r
    thr_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate);\r
    while (_LOCKOWNER(fp) != NULL)\r
      cond_wait(&_LOCKCOND(fp), &_LOCK(fp));\r
    thr_setcancelstate(oldstate, NULL);\r
    _LOCKOWNER(fp) = thr_self();\r
    _LOCKCOUNT(fp) = 1;\r
    if (internal)\r
      _LOCKINTERNAL(fp) = 1;\r
  }\r
\r
  if (_LOCKINTERNAL(fp) == 1)\r
    /* stash cancellation state and disable */\r
    thr_setcancelstate(PTHREAD_CANCEL_DISABLE,\r
        &_LOCKCANCELSTATE(fp));\r
\r
  mutex_unlock(&_LOCK(fp));\r
}\r
\r
void\r
__funlockfile_internal(FILE *fp, int internal)\r
{\r
\r
  if (__isthreaded == 0)\r
    return;\r
\r
  mutex_lock(&_LOCK(fp));\r
\r
  if (internal) {\r
    _LOCKINTERNAL(fp)--;\r
    if (_LOCKINTERNAL(fp) == 0)\r
      thr_setcancelstate(_LOCKCANCELSTATE(fp), NULL);\r
  }\r
\r
  _LOCKCOUNT(fp)--;\r
  if (_LOCKCOUNT(fp) == 0) {\r
    _LOCKOWNER(fp) = NULL;\r
    cond_signal(&_LOCKCOND(fp));\r
  }\r
\r
  mutex_unlock(&_LOCK(fp));\r
}\r
\r
#else /* _REENTRANT */\r
\r
void\r
flockfile(FILE *fp)\r
{\r
  /* LINTED deliberate lack of effect */\r
  (void)fp;\r
\r
  return;\r
}\r
\r
int\r
ftrylockfile(FILE *fp)\r
{\r
  /* LINTED deliberate lack of effect */\r
  (void)fp;\r
\r
  return (0);\r
}\r
\r
void\r
funlockfile(FILE *fp)\r
{\r
  /* LINTED deliberate lack of effect */\r
  (void)fp;\r
\r
  return;\r
}\r
\r
#endif /* _REENTRANT */\r