/****************************************************************************
* netutils/thttpd/timers.c
* FD watcher routines for poll()
*
* Copyright (C) 2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Derived from the file of the same name in the original THTTPD package:
*
* Copyright � 1999,2000 by Jef Poskanzer <jef@mail.acme.com>.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <stdlib.h>
#include <debug.h>
#include <poll.h>
#include <debug.h>
#include "config.h"
#include "thttpd_alloc.h"
#include "fdwatch.h"
#ifdef CONFIG_THTTPD
/****************************************************************************
* Pre-Processor Definitions
****************************************************************************/
/* Debug output from this file is normally suppressed. If enabled, be aware
* that output to stdout will interfere with CGI programs (you could use the
* the low-level debug (lldbg) functions which probably do not use stdout
*/
#ifdef CONFIG_THTTPD_FDWATCH_DEBUG
# ifdef CONFIG_CPP_HAVE_VARARGS
# define fwdbg(format, arg...) ndbg(format, ##arg)
# define fwlldbg(format, arg...) nlldbg(format, ##arg)
# define fwvdbg(format, arg...) nvdbg(format, ##arg)
# define fwllvdbg(format, arg...) nllvdbg(format, ##arg)
# else
# define fwdbg ndbg
# define fwlldbg nlldbg
# define fwvdbg nvdbg
# define fwllvdbg nllvdbg
# endif
#else
# ifdef CONFIG_CPP_HAVE_VARARGS
# define fwdbg(x...)
# define fwlldbg(x...)
# define fwvdbg(x...)
# define fwllvdbg(x...)
# else
# define fwdbg (void)
# define fwlldbg (void)
# define fwvdbg (void)
# define fwllvdbg (void)
# endif
#endif
#ifndef MIN
# define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
#ifdef CONFIG_THTTPD_FDWATCH_DEBUG
static void fdwatch_dump(const char *msg, FAR struct fdwatch_s *fw)
{
int i;
fwvdbg("%s\n", msg);
fwvdbg("nwatched: %d nfds: %d\n", fw->nwatched, fw->nfds);
for (i = 0; i < fw->nwatched; i++)
{
fwvdbg("%2d. pollfds: {fd: %d events: %02x revents: %02x} client: %p\n",
i+1, fw->pollfds[i].fd, fw->pollfds[i].events,
fw->pollfds[i].revents, fw->client[i]);
}
fwvdbg("nactive: %d next: %d\n", fw->nactive, fw->next);
for (i = 0; i < fw->nactive; i++)
{
fwvdbg("%2d. %d active\n", i, fw->ready[i]);
}
}
#else
# define fdwatch_dump(m,f)
#endif
static int fdwatch_pollndx(FAR struct fdwatch_s *fw, int fd)
{
int pollndx;
/* Get the index associated with the fd */
for (pollndx = 0; pollndx < fw->nwatched; pollndx++)
{
if (fw->pollfds[pollndx].fd == fd)
{
fwvdbg("pollndx: %d\n", pollndx);
return pollndx;
}
}
fwdbg("No poll index for fd %d: %d\n", fd);
return -1;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/* Initialize the fdwatch data structures. Returns -1 on failure. */
struct fdwatch_s *fdwatch_initialize(int nfds)
{
FAR struct fdwatch_s *fw;
/* Allocate the fdwatch data structure */
fw = (struct fdwatch_s*)zalloc(sizeof(struct fdwatch_s));
if (!fw)
{
fwdbg("Failed to allocate fdwatch\n");
return NULL;
}
/* Initialize the fdwatch data structures. */
fw->nfds = nfds;
fw->client = (void**)httpd_malloc(sizeof(void*) * nfds);
if (!fw->client)
{
goto errout_with_allocations;
}
fw->pollfds = (struct pollfd*)httpd_malloc(sizeof(struct pollfd) * nfds);
if (!fw->pollfds)
{
goto errout_with_allocations;
}
fw->ready = (uint8_t*)httpd_malloc(sizeof(uint8_t) * nfds);
if (!fw->ready)
{
goto errout_with_allocations;
}
fdwatch_dump("Initial state:", fw);
return fw;
errout_with_allocations:
fdwatch_uninitialize(fw);
return NULL;
}
/* Uninitialize the fwdatch data structure */
void fdwatch_uninitialize(struct fdwatch_s *fw)
{
if (fw)
{
fdwatch_dump("Uninitializing:", fw);
if (fw->client)
{
httpd_free(fw->client);
}
if (fw->pollfds)
{
httpd_free(fw->pollfds);
}
if (fw->ready)
{
httpd_free(fw->ready);
}
httpd_free(fw);
}
}
/* Add a descriptor to the watch list. rw is either FDW_READ or FDW_WRITE. */
void fdwatch_add_fd(struct fdwatch_s *fw, int fd, void *client_data)
{
fwvdbg("fd: %d client_data: %p\n", fd, client_data);
fdwatch_dump("Before adding:", fw);
if (fw->nwatched >= fw->nfds)
{
fwdbg("too many fds\n");
return;
}
/* Save the new fd at the end of the list */
fw->pollfds[fw->nwatched].fd = fd;
fw->pollfds[fw->nwatched].events = POLLIN;
fw->client[fw->nwatched] = client_data;
/* Increment the count of watched descriptors */
fw->nwatched++;
fdwatch_dump("After adding:", fw);
}
/* Remove a descriptor from the watch list. */
void fdwatch_del_fd(struct fdwatch_s *fw, int fd)
{
int pollndx;
fwvdbg("fd: %d\n", fd);
fdwatch_dump("Before deleting:", fw);
/* Get the index associated with the fd */
pollndx = fdwatch_pollndx(fw, fd);
if (pollndx >= 0)
{
/* Decrement the number of fds in the poll table */
fw->nwatched--;
/* Replace the deleted one with the one at the the end
* of the list.
*/
if (pollndx != fw->nwatched)
{
fw->pollfds[pollndx] = fw->pollfds[fw->nwatched];
fw->client[pollndx] = fw->client[fw->nwatched];
}
}
fdwatch_dump("After deleting:", fw);
}
/* Do the watch. Return value is the number of descriptors that are ready,
* or 0 if the timeout expired, or -1 on errors. A timeout of INFTIM means
* wait indefinitely.
*/
int fdwatch(struct fdwatch_s *fw, long timeout_msecs)
{
int ret;
int i;
/* Wait for activity on any of the desciptors. When poll() returns, ret
* will hold the number of descriptors with activity (or zero on a timeout
* or <0 on an error.
*/
fdwatch_dump("Before waiting:", fw);
fwvdbg("Waiting... (timeout %d)\n", timeout_msecs);
fw->nactive = 0;
fw->next = 0;
ret = poll(fw->pollfds, fw->nwatched, (int)timeout_msecs);
fwvdbg("Awakened: %d\n", ret);
/* Look through all of the descriptors and make a list of all of them than
* have activity.
*/
if (ret > 0)
{
for (i = 0; i < fw->nwatched; i++)
{
/* Is there activity on this descriptor? */
if (fw->pollfds[i].revents & (POLLIN | POLLERR | POLLHUP | POLLNVAL))
{
/* Yes... save it in a shorter list */
fwvdbg("pollndx: %d fd: %d revents: %04x\n",
i, fw->pollfds[i].fd, fw->pollfds[i].revents);
fw->ready[fw->nactive++] = fw->pollfds[i].fd;
if (fw->nactive == ret)
{
/* We have all of them, break out early */
break;
}
}
}
}
/* Return the number of descriptors with activity */
fwvdbg("nactive: %d\n", fw->nactive);
fdwatch_dump("After wakeup:", fw);
return ret;
}
/* Check if a descriptor was ready. */
int fdwatch_check_fd(struct fdwatch_s *fw, int fd)
{
int pollndx;
fwvdbg("fd: %d\n", fd);
fdwatch_dump("Checking:", fw);
/* Get the index associated with the fd */
pollndx = fdwatch_pollndx(fw, fd);
if (pollndx >= 0 && (fw->pollfds[pollndx].revents & POLLERR) == 0)
{
return fw->pollfds[pollndx].revents & (POLLIN | POLLHUP | POLLNVAL);
}
fwvdbg("POLLERR fd: %d\n", fd);
return 0;
}
void *fdwatch_get_next_client_data(struct fdwatch_s *fw)
{
fdwatch_dump("Before getting client data:", fw);
if (fw->next >= fw->nwatched)
{
fwvdbg("All client data returned: %d\n", fw->next);
return (void*)-1;
}
fwvdbg("client_data[%d]: %p\n", fw->next, fw->client[fw->next]);
return fw->client[fw->next++];
}
#endif /* CONFIG_THTTPD */
