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Diffstat (limited to 'nuttx/net/uip/uip_igmptimer.c')
-rwxr-xr-x | nuttx/net/uip/uip_igmptimer.c | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/nuttx/net/uip/uip_igmptimer.c b/nuttx/net/uip/uip_igmptimer.c new file mode 100755 index 000000000..27e2f9ff0 --- /dev/null +++ b/nuttx/net/uip/uip_igmptimer.c @@ -0,0 +1,257 @@ +/**************************************************************************** + * net/uip/uip_igmptimer.c + * + * Copyright (C) 2010-2011 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * The NuttX implementation of IGMP was inspired by the IGMP add-on for the + * lwIP TCP/IP stack by Steve Reynolds: + * + * Copyright (c) 2002 CITEL Technologies Ltd. + * 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. Neither the name of CITEL Technologies Ltd nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES 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 CITEL TECHNOLOGIES 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 <nuttx/compiler.h> + +#include <wdog.h> +#include <assert.h> +#include <debug.h> + +#include <nuttx/net/uip/uipopt.h> +#include <nuttx/net/uip/uip.h> +#include <nuttx/net/uip/uip-igmp.h> + +#include "uip_internal.h" + +#ifdef CONFIG_NET_IGMP + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/* Debug ********************************************************************/ + +#undef IGMP_GTMRDEBUG /* Define to enable detailed IGMP group debug */ + +#ifndef CONFIG_NET_IGMP +# undef IGMP_GTMRDEBUG +#endif + +#ifdef CONFIG_CPP_HAVE_VARARGS +# ifdef IGMP_GTMRDEBUG +# define gtmrdbg(format, arg...) ndbg(format, ##arg) +# define gtmrlldbg(format, arg...) nlldbg(format, ##arg) +# define gtmrvdbg(format, arg...) nvdbg(format, ##arg) +# define gtmrllvdbg(format, arg...) nllvdbg(format, ##arg) +# else +# define gtmrdbg(x...) +# define gtmrlldbg(x...) +# define gtmrvdbg(x...) +# define gtmrllvdbg(x...) +# endif +#else +# ifdef IGMP_GTMRDEBUG +# define gtmrdbg ndbg +# define gtmrlldbg nlldbg +# define gtmrvdbg nvdbg +# define gtmrllvdbg nllvdbg +# else +# define gtmrdbg (void) +# define gtmrlldbg (void) +# define gtmrvdbg (void) +# define gtmrllvdbg (void) +# endif +#endif + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: uip_igmptimeout + * + * Description: + * Timeout watchdog handler. + * + * Assumptions: + * This function is called from the wdog timer handler which runs in the + * context of the timer interrupt handler. + * + ****************************************************************************/ + +static void uip_igmptimeout(int argc, uint32_t arg, ...) +{ + FAR struct igmp_group_s *group; + + /* If the state is DELAYING_MEMBER then we send a report for this group */ + + nllvdbg("Timeout!\n"); + group = (FAR struct igmp_group_s *)arg; + DEBUGASSERT(argc == 1 && group); + + /* If the group exists and is no an IDLE MEMBER, then it must be a DELAYING + * member. Race conditions are avoided because (1) the timer is not started + * until after the first IGMPv2_MEMBERSHIP_REPORT during the join, and (2) + * the timer is canceled before sending the IGMP_LEAVE_GROUP during a leave. + */ + + if (!IS_IDLEMEMBER(group->flags)) + { + /* Schedule (and forget) the Membership Report. NOTE: + * Since we are executing from a timer interrupt, we cannot wait + * for the message to be sent. + */ + + IGMP_STATINCR(uip_stat.igmp.report_sched); + uip_igmpschedmsg(group, IGMPv2_MEMBERSHIP_REPORT); + + /* Also note: The Membership Report is sent at most two times becasue + * the timer is not reset here. Hmm.. does this mean that the group + * is stranded if both reports were lost? This is consistent with the + * RFC that states: "To cover the possibility of the initial Membership + * Report being lost or damaged, it is recommended that it be repeated + * once or twice after shortdelays [Unsolicited Report Interval]..." + */ + } +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: uip_igmpstarttimer + * + * Description: + * Start the IGMP timer. + * + * Assumptions: + * This function may be called from most any context. + * + ****************************************************************************/ + +int uip_decisec2tick(int decisecs) +{ + /* Convert the deci-second comparison value to clock ticks. The CLK_TCK + * value is the number of clock ticks per second; decisecs argument is the + * maximum delay in 100's of milliseconds. CLK_TCK/10 is then the number + * of clock ticks in 100 milliseconds. + */ + + return CLK_TCK * decisecs / 10; +} + +/**************************************************************************** + * Name: uip_igmpstartticks and uip_igmpstarttimer + * + * Description: + * Start the IGMP timer with differing time units (ticks or deciseconds). + * + * Assumptions: + * This function may be called from most any context. + * + ****************************************************************************/ + +void uip_igmpstartticks(FAR struct igmp_group_s *group, int ticks) +{ + int ret; + + /* Start the timer */ + + gtmrlldbg("ticks: %d\n", ticks); + ret = wd_start(group->wdog, ticks, uip_igmptimeout, 1, (uint32_t)group); + DEBUGASSERT(ret == OK); +} + +void uip_igmpstarttimer(FAR struct igmp_group_s *group, uint8_t decisecs) +{ + /* Convert the decisec value to system clock ticks and start the timer. + * Important!! this should be a random timer from 0 to decisecs + */ + + gtmrdbg("decisecs: %d\n", decisecs); + uip_igmpstartticks(group, uip_decisec2tick(decisecs)); +} + +/**************************************************************************** + * Name: uip_igmpcmptimer + * + * Description: + * Compare the timer remaining on the watching timer to the deci-second + * value. If maxticks > ticks-remaining, then (1) cancel the timer (to + * avoid race conditions) and return true. + * + * Assumptions: + * This function may be called from most any context. If true is retuend + * then the caller must call uip_igmpstartticks() to restart the timer + * + ****************************************************************************/ + +bool uip_igmpcmptimer(FAR struct igmp_group_s *group, int maxticks) +{ + uip_lock_t flags; + int remaining; + + /* Disable interrupts so that there is no race condition with the actual + * timer expiration. + */ + + flags = uip_lock(); + + /* Get the timer remaining on the watchdog. A time of <= zero means that + * the watchdog was never started. + */ + + remaining = wd_gettime(group->wdog); + + /* A remaining time of zero means that the watchdog was never started + * or has already expired. That case should be covered in the following + * test as well. + */ + + gtmrdbg("maxticks: %d remaining: %d\n", maxticks, remaining); + if (maxticks > remaining) + { + /* Cancel the watchdog timer and return true */ + + wd_cancel(group->wdog); + uip_unlock(flags); + return true; + } + + uip_unlock(flags); + return false; +} + +#endif /* CONFIG_NET_IGMP */ |