lwip-contrib-mac/ports/unix/sys_arch.c
davidhaas 7d1204e144 Fixed SYS_ARCH_PROTECT macros when NO_SYS is not defined.
Added documentation for lightweight protection.

Fixed debug statement in ip.c.

Removed tabs in files I changed.
2003-02-18 21:14:26 +00:00

513 lines
14 KiB
C

/*
* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
/*
* Wed Apr 17 16:05:29 EDT 2002 (James Roth)
*
* - Fixed an unlikely sys_thread_new() race condition.
*
* - Made current_thread() work with threads which where
* not created with sys_thread_new(). This includes
* the main thread and threads made with pthread_create().
*
* - Catch overflows where more than SYS_MBOX_SIZE messages
* are waiting to be read. The sys_mbox_post() routine
* will block until there is more room instead of just
* leaking messages.
*/
#include "lwip/debug.h"
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include "lwip/sys.h"
#include "lwip/opt.h"
#include "lwip/stats.h"
#define UMAX(a, b) ((a) > (b) ? (a) : (b))
static struct sys_thread *threads = NULL;
static pthread_mutex_t threads_mutex = PTHREAD_MUTEX_INITIALIZER;
struct sys_mbox_msg {
struct sys_mbox_msg *next;
void *msg;
};
#define SYS_MBOX_SIZE 128
struct sys_mbox {
int first, last;
void *msgs[SYS_MBOX_SIZE];
struct sys_sem *mail;
struct sys_sem *mutex;
int wait_send;
};
struct sys_sem {
unsigned int c;
pthread_cond_t cond;
pthread_mutex_t mutex;
};
struct sys_thread {
struct sys_thread *next;
struct sys_timeouts timeouts;
pthread_t pthread;
};
static struct timeval starttime;
static pthread_mutex_t lwprot_mutex = PTHREAD_MUTEX_INITIALIZER;
static pthread_t lwprot_thread = (pthread_t) 0xDEAD;
static int lwprot_count = 0;
static struct sys_sem *sys_sem_new_(u8_t count);
static void sys_sem_free_(struct sys_sem *sem);
static u32_t cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex,
u32_t timeout);
/*-----------------------------------------------------------------------------------*/
static struct sys_thread *
introduce_thread(pthread_t id)
{
struct sys_thread *thread;
thread = malloc(sizeof(struct sys_thread));
if(thread) {
pthread_mutex_lock(&threads_mutex);
thread->next = threads;
thread->timeouts.next = NULL;
thread->pthread = id;
threads = thread;
pthread_mutex_unlock(&threads_mutex);
}
return thread;
}
/*-----------------------------------------------------------------------------------*/
static struct sys_thread *
current_thread(void)
{
struct sys_thread *st;
pthread_t pt;
pt = pthread_self();
pthread_mutex_lock(&threads_mutex);
for(st = threads; st != NULL; st = st->next) {
if(pthread_equal(st->pthread, pt)) {
pthread_mutex_unlock(&threads_mutex);
return st;
}
}
pthread_mutex_unlock(&threads_mutex);
st = introduce_thread(pt);
if(!st) {
printf("current_thread???\n");
abort();
}
return st;
}
/*-----------------------------------------------------------------------------------*/
sys_thread_t
sys_thread_new(void (*function)(void *arg), void *arg)
{
int code;
pthread_t tmp;
struct sys_thread *st = NULL;
code = pthread_create(&tmp,
NULL,
(void *(*)(void *))
function,
arg);
if(0 == code) {
st = introduce_thread(tmp);
}
if(NULL == st) {
DEBUGF(SYS_DEBUG, ("sys_thread_new: pthread_create %d, st = 0x%x",
code, (int)st));
abort();
}
return st;
}
/*-----------------------------------------------------------------------------------*/
struct sys_mbox *
sys_mbox_new()
{
struct sys_mbox *mbox;
mbox = malloc(sizeof(struct sys_mbox));
mbox->first = mbox->last = 0;
mbox->mail = sys_sem_new_(0);
mbox->mutex = sys_sem_new_(1);
mbox->wait_send = 0;
#ifdef SYS_STATS
lwip_stats.sys.mbox.used++;
if(lwip_stats.sys.mbox.used > lwip_stats.sys.mbox.max) {
lwip_stats.sys.mbox.max = lwip_stats.sys.mbox.used;
}
#endif /* SYS_STATS */
return mbox;
}
/*-----------------------------------------------------------------------------------*/
void
sys_mbox_free(struct sys_mbox *mbox)
{
if(mbox != SYS_MBOX_NULL) {
#ifdef SYS_STATS
lwip_stats.sys.mbox.used--;
#endif /* SYS_STATS */
sys_sem_wait(mbox->mutex);
sys_sem_free_(mbox->mail);
sys_sem_free_(mbox->mutex);
mbox->mail = mbox->mutex = NULL;
/* DEBUGF("sys_mbox_free: mbox 0x%lx\n", mbox); */
free(mbox);
}
}
/*-----------------------------------------------------------------------------------*/
void
sys_mbox_post(struct sys_mbox *mbox, void *msg)
{
u8_t first;
sys_sem_wait(mbox->mutex);
DEBUGF(SYS_DEBUG, ("sys_mbox_post: mbox %p msg %p\n", (void *)mbox, (void *)msg));
while((mbox->last + 1) >= (mbox->first + SYS_MBOX_SIZE)) {
mbox->wait_send++;
sys_sem_signal(mbox->mutex);
sys_arch_sem_wait(mbox->mail, 0);
sys_arch_sem_wait(mbox->mutex, 0);
mbox->wait_send--;
}
mbox->msgs[mbox->last % SYS_MBOX_SIZE] = msg;
if(mbox->last == mbox->first) {
first = 1;
} else {
first = 0;
}
mbox->last++;
if(first) {
sys_sem_signal(mbox->mail);
}
sys_sem_signal(mbox->mutex);
}
/*-----------------------------------------------------------------------------------*/
u32_t
sys_arch_mbox_fetch(struct sys_mbox *mbox, void **msg, u32_t timeout)
{
u32_t time = 1;
/* The mutex lock is quick so we don't bother with the timeout
stuff here. */
sys_arch_sem_wait(mbox->mutex, 0);
while(mbox->first == mbox->last) {
sys_sem_signal(mbox->mutex);
/* We block while waiting for a mail to arrive in the mailbox. We
must be prepared to timeout. */
if(timeout != 0) {
time = sys_arch_sem_wait(mbox->mail, timeout);
/* If time == 0, the sem_wait timed out, and we return 0. */
if(time == 0) {
return 0;
}
} else {
sys_arch_sem_wait(mbox->mail, 0);
}
sys_arch_sem_wait(mbox->mutex, 0);
}
DEBUGF(SYS_DEBUG, ("sys_mbox_fetch: mbox %p msg %p\n", (void *)mbox, *msg));
if(msg != NULL) {
*msg = mbox->msgs[mbox->first % SYS_MBOX_SIZE];
}
mbox->first++;
if(mbox->wait_send) {
sys_sem_signal(mbox->mail);
}
sys_sem_signal(mbox->mutex);
return time;
}
/*-----------------------------------------------------------------------------------*/
struct sys_sem *
sys_sem_new(u8_t count)
{
#ifdef SYS_STATS
lwip_stats.sys.sem.used++;
if(lwip_stats.sys.sem.used > lwip_stats.sys.sem.max) {
lwip_stats.sys.sem.max = lwip_stats.sys.sem.used;
}
#endif /* SYS_STATS */
return sys_sem_new_(count);
}
/*-----------------------------------------------------------------------------------*/
static struct sys_sem *
sys_sem_new_(u8_t count)
{
struct sys_sem *sem;
sem = malloc(sizeof(struct sys_sem));
sem->c = count;
pthread_cond_init(&(sem->cond), NULL);
pthread_mutex_init(&(sem->mutex), NULL);
return sem;
}
/*-----------------------------------------------------------------------------------*/
static u32_t
cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex, u32_t timeout)
{
int tdiff;
unsigned long sec, usec;
struct timeval rtime1, rtime2;
struct timespec ts;
struct timezone tz;
int retval;
if(timeout > 0) {
/* Get a timestamp and add the timeout value. */
gettimeofday(&rtime1, &tz);
sec = rtime1.tv_sec;
usec = rtime1.tv_usec;
usec += timeout % 1000 * 1000;
sec += (int)(timeout / 1000) + (int)(usec / 1000000);
usec = usec % 1000000;
ts.tv_nsec = usec * 1000;
ts.tv_sec = sec;
retval = pthread_cond_timedwait(cond, mutex, &ts);
if(retval == ETIMEDOUT) {
return 0;
} else {
/* Calculate for how long we waited for the cond. */
gettimeofday(&rtime2, &tz);
tdiff = (rtime2.tv_sec - rtime1.tv_sec) * 1000 +
(rtime2.tv_usec - rtime1.tv_usec) / 1000;
if(tdiff <= 0) {
return 1;
}
return tdiff;
}
} else {
pthread_cond_wait(cond, mutex);
return 0;
}
}
/*-----------------------------------------------------------------------------------*/
u32_t
sys_arch_sem_wait(struct sys_sem *sem, u32_t timeout)
{
u32_t time = 1;
pthread_mutex_lock(&(sem->mutex));
while(sem->c <= 0) {
if(timeout > 0) {
time = cond_wait(&(sem->cond), &(sem->mutex), timeout);
if(time == 0) {
pthread_mutex_unlock(&(sem->mutex));
return 0;
}
/* pthread_mutex_unlock(&(sem->mutex));
return time; */
} else {
cond_wait(&(sem->cond), &(sem->mutex), 0);
}
}
sem->c--;
pthread_mutex_unlock(&(sem->mutex));
return time;
}
/*-----------------------------------------------------------------------------------*/
void
sys_sem_signal(struct sys_sem *sem)
{
pthread_mutex_lock(&(sem->mutex));
sem->c++;
if(sem->c > 1) {
sem->c = 1;
}
pthread_cond_broadcast(&(sem->cond));
pthread_mutex_unlock(&(sem->mutex));
}
/*-----------------------------------------------------------------------------------*/
void
sys_sem_free(struct sys_sem *sem)
{
if(sem != SYS_SEM_NULL) {
#ifdef SYS_STATS
lwip_stats.sys.sem.used--;
#endif /* SYS_STATS */
sys_sem_free_(sem);
}
}
/*-----------------------------------------------------------------------------------*/
static void
sys_sem_free_(struct sys_sem *sem)
{
pthread_cond_destroy(&(sem->cond));
pthread_mutex_destroy(&(sem->mutex));
free(sem);
}
/*-----------------------------------------------------------------------------------*/
unsigned long
sys_unix_now()
{
struct timeval tv;
struct timezone tz;
long sec, usec;
unsigned long msec;
gettimeofday(&tv, &tz);
sec = tv.tv_sec - starttime.tv_sec;
usec = tv.tv_usec - starttime.tv_usec;
msec = sec * 1000 + usec / 1000;
return msec;
}
/*-----------------------------------------------------------------------------------*/
void
sys_init()
{
struct timezone tz;
gettimeofday(&starttime, &tz);
}
/*-----------------------------------------------------------------------------------*/
struct sys_timeouts *
sys_arch_timeouts(void)
{
struct sys_thread *thread;
thread = current_thread();
return &thread->timeouts;
}
/*-----------------------------------------------------------------------------------*/
/** sys_prot_t sys_arch_protect(void)
This optional function does a "fast" critical region protection and returns
the previous protection level. This function is only called during very short
critical regions. An embedded system which supports ISR-based drivers might
want to implement this function by disabling interrupts. Task-based systems
might want to implement this by using a mutex or disabling tasking. This
function should support recursive calls from the same task or interrupt. In
other words, sys_arch_protect() could be called while already protected. In
that case the return value indicates that it is already protected.
sys_arch_protect() is only required if your port is supporting an operating
system.
*/
sys_prot_t
sys_arch_protect(void)
{
/* Note that for the UNIX port, we are using a lightweight mutex, and our
* own counter (which is locked by the mutex). The return code is not actually
* used. */
if (lwprot_thread != pthread_self())
{
/* We are locking the mutex where it has not been locked before *
* or is being locked by another thread */
pthread_mutex_lock(&lwprot_mutex);
lwprot_thread = pthread_self();
lwprot_count = 1;
}
else
/* It is already locked by THIS thread */
lwprot_count++;
return 0;
}
/*-----------------------------------------------------------------------------------*/
/** void sys_arch_unprotect(sys_prot_t pval)
This optional function does a "fast" set of critical region protection to the
value specified by pval. See the documentation for sys_arch_protect() for
more information. This function is only required if your port is supporting
an operating system.
*/
void
sys_arch_unprotect(sys_prot_t pval)
{
if (lwprot_thread == pthread_self())
{
if (--lwprot_count == 0)
{
lwprot_thread = (pthread_t) 0xDEAD;
pthread_mutex_unlock(&lwprot_mutex);
}
}
}
/*-----------------------------------------------------------------------------------*/