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/* ath.c - Thread-safeness library.
Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of Libgcrypt.
Libgcrypt 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 2.1 of
the License, or (at your option) any later version.
Libgcrypt 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 Libgcrypt; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <assert.h> /* Right: We need to use assert and not gcry_assert. */
#include <unistd.h>
#ifdef HAVE_SYS_SELECT_H
# include <sys/select.h>
#else
# include <sys/time.h>
#endif
#include <sys/types.h>
#ifndef _WIN32
#include <sys/wait.h>
#endif
#include <errno.h>
#include "ath.h"
/* The interface table. */
static struct ath_ops ops;
/* True if we should use the external callbacks. */
static int ops_set;
/* For the dummy interface. */
#define MUTEX_UNLOCKED ((ath_mutex_t) 0)
#define MUTEX_LOCKED ((ath_mutex_t) 1)
#define MUTEX_DESTROYED ((ath_mutex_t) 2)
/* Return the thread type from the option field. */
#define GET_OPTION(a) ((a) & 0xff)
/* Return the version number from the option field. */
#define GET_VERSION(a) (((a) >> 8)& 0xff)
/* The lock we take while checking for lazy lock initialization. */
static ath_mutex_t check_init_lock = ATH_MUTEX_INITIALIZER;
int
ath_init (void)
{
int err = 0;
if (ops_set)
{
if (ops.init)
err = (*ops.init) ();
if (err)
return err;
err = (*ops.mutex_init) (&check_init_lock);
}
return err;
}
/* Initialize the locking library. Returns 0 if the operation was
successful, EINVAL if the operation table was invalid and EBUSY if
we already were initialized. */
gpg_err_code_t
ath_install (struct ath_ops *ath_ops, int check_only)
{
if (check_only)
{
unsigned int option = 0;
/* Check if the requested thread option is compatible to the
thread option we are already committed to. */
if (ath_ops)
option = ath_ops->option;
if (!ops_set && GET_OPTION (option))
return GPG_ERR_NOT_SUPPORTED;
if (GET_OPTION (ops.option) == ATH_THREAD_OPTION_USER
|| GET_OPTION (option) == ATH_THREAD_OPTION_USER
|| GET_OPTION (ops.option) != GET_OPTION (option)
|| GET_VERSION (ops.option) != GET_VERSION (option))
return GPG_ERR_NOT_SUPPORTED;
return 0;
}
if (ath_ops)
{
/* It is convenient to not require DESTROY. */
if (!ath_ops->mutex_init || !ath_ops->mutex_lock
|| !ath_ops->mutex_unlock)
return GPG_ERR_INV_ARG;
ops = *ath_ops;
ops_set = 1;
}
else
ops_set = 0;
return 0;
}
static int
mutex_init (ath_mutex_t *lock, int just_check)
{
int err = 0;
if (just_check)
(*ops.mutex_lock) (&check_init_lock);
if (*lock == ATH_MUTEX_INITIALIZER || !just_check)
err = (*ops.mutex_init) (lock);
if (just_check)
(*ops.mutex_unlock) (&check_init_lock);
return err;
}
int
ath_mutex_init (ath_mutex_t *lock)
{
if (ops_set)
return mutex_init (lock, 0);
#ifndef NDEBUG
*lock = MUTEX_UNLOCKED;
#endif
return 0;
}
int
ath_mutex_destroy (ath_mutex_t *lock)
{
if (ops_set)
{
if (!ops.mutex_destroy)
return 0;
(*ops.mutex_lock) (&check_init_lock);
if (*lock == ATH_MUTEX_INITIALIZER)
{
(*ops.mutex_unlock) (&check_init_lock);
return 0;
}
(*ops.mutex_unlock) (&check_init_lock);
return (*ops.mutex_destroy) (lock);
}
#ifndef NDEBUG
assert (*lock == MUTEX_UNLOCKED);
*lock = MUTEX_DESTROYED;
#endif
return 0;
}
int
ath_mutex_lock (ath_mutex_t *lock)
{
if (ops_set)
{
int ret = mutex_init (lock, 1);
if (ret)
return ret;
return (*ops.mutex_lock) (lock);
}
#ifndef NDEBUG
assert (*lock == MUTEX_UNLOCKED);
*lock = MUTEX_LOCKED;
#endif
return 0;
}
int
ath_mutex_unlock (ath_mutex_t *lock)
{
if (ops_set)
{
int ret = mutex_init (lock, 1);
if (ret)
return ret;
return (*ops.mutex_unlock) (lock);
}
#ifndef NDEBUG
assert (*lock == MUTEX_LOCKED);
*lock = MUTEX_UNLOCKED;
#endif
return 0;
}
ssize_t
ath_read (int fd, void *buf, size_t nbytes)
{
if (ops_set && ops.read)
return (*ops.read) (fd, buf, nbytes);
else
return read (fd, buf, nbytes);
}
ssize_t
ath_write (int fd, const void *buf, size_t nbytes)
{
if (ops_set && ops.write)
return (*ops.write) (fd, buf, nbytes);
else
return write (fd, buf, nbytes);
}
ssize_t
#ifdef _WIN32
ath_select (int nfd, void *rset, void *wset, void *eset,
struct timeval *timeout)
#else
ath_select (int nfd, fd_set *rset, fd_set *wset, fd_set *eset,
struct timeval *timeout)
#endif
{
if (ops_set && ops.select)
return (*ops.select) (nfd, rset, wset, eset, timeout);
else
#ifdef _WIN32
return -1;
#else
return select (nfd, rset, wset, eset, timeout);
#endif
}
ssize_t
ath_waitpid (pid_t pid, int *status, int options)
{
if (ops_set && ops.waitpid)
return (*ops.waitpid) (pid, status, options);
else
#ifdef _WIN32
return -1;
#else
return waitpid (pid, status, options);
#endif
}
int
#ifdef _WIN32
ath_accept (int s, void *addr, int *length_ptr)
#else
ath_accept (int s, struct sockaddr *addr, socklen_t *length_ptr)
#endif
{
if (ops_set && ops.accept)
return (*ops.accept) (s, addr, length_ptr);
else
#ifdef _WIN32
return -1;
#else
return accept (s, addr, length_ptr);
#endif
}
int
#ifdef _WIN32
ath_connect (int s, void *addr, int length)
#else
ath_connect (int s, struct sockaddr *addr, socklen_t length)
#endif
{
if (ops_set && ops.connect)
return (*ops.connect) (s, addr, length);
else
#ifdef _WIN32
return -1;
#else
return connect (s, addr, length);
#endif
}
int
#ifdef _WIN32
ath_sendmsg (int s, const void *msg, int flags)
#else
ath_sendmsg (int s, const struct msghdr *msg, int flags)
#endif
{
if (ops_set && ops.sendmsg)
return (*ops.sendmsg) (s, msg, flags);
else
#ifdef _WIN32
return -1;
#else
return sendmsg (s, msg, flags);
#endif
}
int
#ifdef _WIN32
ath_recvmsg (int s, void *msg, int flags)
#else
ath_recvmsg (int s, struct msghdr *msg, int flags)
#endif
{
if (ops_set && ops.recvmsg)
return (*ops.recvmsg) (s, msg, flags);
else
#ifdef _WIN32
return -1;
#else
return recvmsg (s, msg, flags);
#endif
}