| /** |
| * @file |
| * Stack-internal timers implementation. |
| * This file includes timer callbacks for stack-internal timers as well as |
| * functions to set up or stop timers and check for expired timers. |
| * |
| */ |
| |
| /* |
| * Copyright (c) 2001-2004 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> |
| * Simon Goldschmidt |
| * |
| */ |
| |
| #include "lwip/opt.h" |
| |
| #include "lwip/timeouts.h" |
| #include "lwip/priv/tcp_priv.h" |
| |
| #include "lwip/def.h" |
| #include "lwip/memp.h" |
| #include "lwip/priv/tcpip_priv.h" |
| |
| #include "lwip/ip4_frag.h" |
| #include "lwip/etharp.h" |
| #include "lwip/dhcp.h" |
| #include "lwip/autoip.h" |
| #include "lwip/igmp.h" |
| #include "lwip/dns.h" |
| #include "lwip/nd6.h" |
| #include "lwip/ip6_frag.h" |
| #include "lwip/mld6.h" |
| #include "lwip/dhcp6.h" |
| #include "lwip/sys.h" |
| #include "lwip/pbuf.h" |
| |
| #if LWIP_DEBUG_TIMERNAMES |
| #define HANDLER(x) x, #x |
| #else /* LWIP_DEBUG_TIMERNAMES */ |
| #define HANDLER(x) x |
| #endif /* LWIP_DEBUG_TIMERNAMES */ |
| |
| #define LWIP_MAX_TIMEOUT 0x7fffffff |
| |
| /* Check if timer's expiry time is greater than time and care about u32_t wraparounds */ |
| #define TIME_LESS_THAN(t, compare_to) ( (((u32_t)((t)-(compare_to))) > LWIP_MAX_TIMEOUT) ? 1 : 0 ) |
| |
| /** This array contains all stack-internal cyclic timers. To get the number of |
| * timers, use LWIP_ARRAYSIZE() */ |
| const struct lwip_cyclic_timer lwip_cyclic_timers[] = { |
| #if LWIP_TCP |
| /* The TCP timer is a special case: it does not have to run always and |
| is triggered to start from TCP using tcp_timer_needed() */ |
| {TCP_TMR_INTERVAL, HANDLER(tcp_tmr)}, |
| #endif /* LWIP_TCP */ |
| #if LWIP_IPV4 |
| #if IP_REASSEMBLY |
| {IP_TMR_INTERVAL, HANDLER(ip_reass_tmr)}, |
| #endif /* IP_REASSEMBLY */ |
| #if LWIP_ARP |
| {ARP_TMR_INTERVAL, HANDLER(etharp_tmr)}, |
| #endif /* LWIP_ARP */ |
| #if LWIP_DHCP |
| {DHCP_COARSE_TIMER_MSECS, HANDLER(dhcp_coarse_tmr)}, |
| {DHCP_FINE_TIMER_MSECS, HANDLER(dhcp_fine_tmr)}, |
| #endif /* LWIP_DHCP */ |
| #if LWIP_AUTOIP |
| {AUTOIP_TMR_INTERVAL, HANDLER(autoip_tmr)}, |
| #endif /* LWIP_AUTOIP */ |
| #if LWIP_IGMP |
| {IGMP_TMR_INTERVAL, HANDLER(igmp_tmr)}, |
| #endif /* LWIP_IGMP */ |
| #endif /* LWIP_IPV4 */ |
| #if LWIP_DNS |
| {DNS_TMR_INTERVAL, HANDLER(dns_tmr)}, |
| #endif /* LWIP_DNS */ |
| #if LWIP_IPV6 |
| {ND6_TMR_INTERVAL, HANDLER(nd6_tmr)}, |
| #if LWIP_IPV6_REASS |
| {IP6_REASS_TMR_INTERVAL, HANDLER(ip6_reass_tmr)}, |
| #endif /* LWIP_IPV6_REASS */ |
| #if LWIP_IPV6_MLD |
| {MLD6_TMR_INTERVAL, HANDLER(mld6_tmr)}, |
| #endif /* LWIP_IPV6_MLD */ |
| #if LWIP_IPV6_DHCP6 |
| {DHCP6_TIMER_MSECS, HANDLER(dhcp6_tmr)}, |
| #endif /* LWIP_IPV6_DHCP6 */ |
| #endif /* LWIP_IPV6 */ |
| }; |
| const int lwip_num_cyclic_timers = LWIP_ARRAYSIZE(lwip_cyclic_timers); |
| |
| #if LWIP_TIMERS && !LWIP_TIMERS_CUSTOM |
| |
| /** The one and only timeout list */ |
| static struct sys_timeo *next_timeout; |
| |
| static u32_t current_timeout_due_time; |
| |
| #if LWIP_TESTMODE |
| struct sys_timeo** |
| sys_timeouts_get_next_timeout(void) |
| { |
| return &next_timeout; |
| } |
| #endif |
| |
| #if LWIP_TCP |
| /** global variable that shows if the tcp timer is currently scheduled or not */ |
| static int tcpip_tcp_timer_active; |
| |
| /** |
| * Timer callback function that calls tcp_tmr() and reschedules itself. |
| * |
| * @param arg unused argument |
| */ |
| static void |
| tcpip_tcp_timer(void *arg) |
| { |
| LWIP_UNUSED_ARG(arg); |
| |
| /* call TCP timer handler */ |
| tcp_tmr(); |
| /* timer still needed? */ |
| if (tcp_active_pcbs || tcp_tw_pcbs) { |
| /* restart timer */ |
| sys_timeout(TCP_TMR_INTERVAL, tcpip_tcp_timer, NULL); |
| } else { |
| /* disable timer */ |
| tcpip_tcp_timer_active = 0; |
| } |
| } |
| |
| /** |
| * Called from TCP_REG when registering a new PCB: |
| * the reason is to have the TCP timer only running when |
| * there are active (or time-wait) PCBs. |
| */ |
| void |
| tcp_timer_needed(void) |
| { |
| LWIP_ASSERT_CORE_LOCKED(); |
| |
| /* timer is off but needed again? */ |
| if (!tcpip_tcp_timer_active && (tcp_active_pcbs || tcp_tw_pcbs)) { |
| /* enable and start timer */ |
| tcpip_tcp_timer_active = 1; |
| sys_timeout(TCP_TMR_INTERVAL, tcpip_tcp_timer, NULL); |
| } |
| } |
| #endif /* LWIP_TCP */ |
| |
| static void |
| #if LWIP_DEBUG_TIMERNAMES |
| sys_timeout_abs(u32_t abs_time, sys_timeout_handler handler, void *arg, const char *handler_name) |
| #else /* LWIP_DEBUG_TIMERNAMES */ |
| sys_timeout_abs(u32_t abs_time, sys_timeout_handler handler, void *arg) |
| #endif |
| { |
| struct sys_timeo *timeout, *t; |
| |
| timeout = (struct sys_timeo *)memp_malloc(MEMP_SYS_TIMEOUT); |
| if (timeout == NULL) { |
| LWIP_ASSERT("sys_timeout: timeout != NULL, pool MEMP_SYS_TIMEOUT is empty", timeout != NULL); |
| return; |
| } |
| |
| timeout->next = NULL; |
| timeout->h = handler; |
| timeout->arg = arg; |
| timeout->time = abs_time; |
| |
| #if LWIP_DEBUG_TIMERNAMES |
| timeout->handler_name = handler_name; |
| LWIP_DEBUGF(TIMERS_DEBUG, ("sys_timeout: %p abs_time=%"U32_F" handler=%s arg=%p\n", |
| (void *)timeout, abs_time, handler_name, (void *)arg)); |
| #endif /* LWIP_DEBUG_TIMERNAMES */ |
| |
| if (next_timeout == NULL) { |
| next_timeout = timeout; |
| return; |
| } |
| if (TIME_LESS_THAN(timeout->time, next_timeout->time)) { |
| timeout->next = next_timeout; |
| next_timeout = timeout; |
| } else { |
| for (t = next_timeout; t != NULL; t = t->next) { |
| if ((t->next == NULL) || TIME_LESS_THAN(timeout->time, t->next->time)) { |
| timeout->next = t->next; |
| t->next = timeout; |
| break; |
| } |
| } |
| } |
| } |
| |
| /** |
| * Timer callback function that calls cyclic->handler() and reschedules itself. |
| * |
| * @param arg unused argument |
| */ |
| #if !LWIP_TESTMODE |
| static |
| #endif |
| void |
| lwip_cyclic_timer(void *arg) |
| { |
| u32_t now; |
| u32_t next_timeout_time; |
| const struct lwip_cyclic_timer *cyclic = (const struct lwip_cyclic_timer *)arg; |
| |
| #if LWIP_DEBUG_TIMERNAMES |
| LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: %s()\n", cyclic->handler_name)); |
| #endif |
| cyclic->handler(); |
| |
| now = sys_now(); |
| next_timeout_time = (u32_t)(current_timeout_due_time + cyclic->interval_ms); /* overflow handled by TIME_LESS_THAN macro */ |
| if (TIME_LESS_THAN(next_timeout_time, now)) { |
| /* timer would immediately expire again -> "overload" -> restart without any correction */ |
| #if LWIP_DEBUG_TIMERNAMES |
| sys_timeout_abs((u32_t)(now + cyclic->interval_ms), lwip_cyclic_timer, arg, cyclic->handler_name); |
| #else |
| sys_timeout_abs((u32_t)(now + cyclic->interval_ms), lwip_cyclic_timer, arg); |
| #endif |
| |
| } else { |
| /* correct cyclic interval with handler execution delay and sys_check_timeouts jitter */ |
| #if LWIP_DEBUG_TIMERNAMES |
| sys_timeout_abs(next_timeout_time, lwip_cyclic_timer, arg, cyclic->handler_name); |
| #else |
| sys_timeout_abs(next_timeout_time, lwip_cyclic_timer, arg); |
| #endif |
| } |
| } |
| |
| /** Initialize this module */ |
| void sys_timeouts_init(void) |
| { |
| size_t i; |
| /* tcp_tmr() at index 0 is started on demand */ |
| for (i = (LWIP_TCP ? 1 : 0); i < LWIP_ARRAYSIZE(lwip_cyclic_timers); i++) { |
| /* we have to cast via size_t to get rid of const warning |
| (this is OK as cyclic_timer() casts back to const* */ |
| sys_timeout(lwip_cyclic_timers[i].interval_ms, lwip_cyclic_timer, LWIP_CONST_CAST(void *, &lwip_cyclic_timers[i])); |
| } |
| } |
| |
| /** |
| * Create a one-shot timer (aka timeout). Timeouts are processed in the |
| * following cases: |
| * - while waiting for a message using sys_timeouts_mbox_fetch() |
| * - by calling sys_check_timeouts() (NO_SYS==1 only) |
| * |
| * @param msecs time in milliseconds after that the timer should expire |
| * @param handler callback function to call when msecs have elapsed |
| * @param arg argument to pass to the callback function |
| */ |
| #if LWIP_DEBUG_TIMERNAMES |
| void |
| sys_timeout_debug(u32_t msecs, sys_timeout_handler handler, void *arg, const char *handler_name) |
| #else /* LWIP_DEBUG_TIMERNAMES */ |
| void |
| sys_timeout(u32_t msecs, sys_timeout_handler handler, void *arg) |
| #endif /* LWIP_DEBUG_TIMERNAMES */ |
| { |
| u32_t next_timeout_time; |
| |
| LWIP_ASSERT_CORE_LOCKED(); |
| |
| LWIP_ASSERT("Timeout time too long, max is LWIP_UINT32_MAX/4 msecs", msecs <= (LWIP_UINT32_MAX / 4)); |
| |
| next_timeout_time = (u32_t)(sys_now() + msecs); /* overflow handled by TIME_LESS_THAN macro */ |
| |
| #if LWIP_DEBUG_TIMERNAMES |
| sys_timeout_abs(next_timeout_time, handler, arg, handler_name); |
| #else |
| sys_timeout_abs(next_timeout_time, handler, arg); |
| #endif |
| } |
| |
| /** |
| * Go through timeout list (for this task only) and remove the first matching |
| * entry (subsequent entries remain untouched), even though the timeout has not |
| * triggered yet. |
| * |
| * @param handler callback function that would be called by the timeout |
| * @param arg callback argument that would be passed to handler |
| */ |
| void |
| sys_untimeout(sys_timeout_handler handler, void *arg) |
| { |
| struct sys_timeo *prev_t, *t; |
| |
| LWIP_ASSERT_CORE_LOCKED(); |
| |
| if (next_timeout == NULL) { |
| return; |
| } |
| |
| for (t = next_timeout, prev_t = NULL; t != NULL; prev_t = t, t = t->next) { |
| if ((t->h == handler) && (t->arg == arg)) { |
| /* We have a match */ |
| /* Unlink from previous in list */ |
| if (prev_t == NULL) { |
| next_timeout = t->next; |
| } else { |
| prev_t->next = t->next; |
| } |
| memp_free(MEMP_SYS_TIMEOUT, t); |
| return; |
| } |
| } |
| return; |
| } |
| |
| /** |
| * @ingroup lwip_nosys |
| * Handle timeouts for NO_SYS==1 (i.e. without using |
| * tcpip_thread/sys_timeouts_mbox_fetch(). Uses sys_now() to call timeout |
| * handler functions when timeouts expire. |
| * |
| * Must be called periodically from your main loop. |
| */ |
| void |
| sys_check_timeouts(void) |
| { |
| u32_t now; |
| |
| LWIP_ASSERT_CORE_LOCKED(); |
| |
| /* Process only timers expired at the start of the function. */ |
| now = sys_now(); |
| |
| do { |
| struct sys_timeo *tmptimeout; |
| sys_timeout_handler handler; |
| void *arg; |
| |
| PBUF_CHECK_FREE_OOSEQ(); |
| |
| tmptimeout = next_timeout; |
| if (tmptimeout == NULL) { |
| return; |
| } |
| |
| if (TIME_LESS_THAN(now, tmptimeout->time)) { |
| return; |
| } |
| |
| /* Timeout has expired */ |
| next_timeout = tmptimeout->next; |
| handler = tmptimeout->h; |
| arg = tmptimeout->arg; |
| current_timeout_due_time = tmptimeout->time; |
| #if LWIP_DEBUG_TIMERNAMES |
| if (handler != NULL) { |
| LWIP_DEBUGF(TIMERS_DEBUG, ("sct calling h=%s t=%"U32_F" arg=%p\n", |
| tmptimeout->handler_name, sys_now() - tmptimeout->time, arg)); |
| } |
| #endif /* LWIP_DEBUG_TIMERNAMES */ |
| memp_free(MEMP_SYS_TIMEOUT, tmptimeout); |
| if (handler != NULL) { |
| handler(arg); |
| } |
| LWIP_TCPIP_THREAD_ALIVE(); |
| |
| /* Repeat until all expired timers have been called */ |
| } while (1); |
| } |
| |
| /** Rebase the timeout times to the current time. |
| * This is necessary if sys_check_timeouts() hasn't been called for a long |
| * time (e.g. while saving energy) to prevent all timer functions of that |
| * period being called. |
| */ |
| void |
| sys_restart_timeouts(void) |
| { |
| u32_t now; |
| u32_t base; |
| struct sys_timeo *t; |
| |
| if (next_timeout == NULL) { |
| return; |
| } |
| |
| now = sys_now(); |
| base = next_timeout->time; |
| |
| for (t = next_timeout; t != NULL; t = t->next) { |
| t->time = (t->time - base) + now; |
| } |
| } |
| |
| /** Return the time left before the next timeout is due. If no timeouts are |
| * enqueued, returns 0xffffffff |
| */ |
| u32_t |
| sys_timeouts_sleeptime(void) |
| { |
| u32_t now; |
| |
| LWIP_ASSERT_CORE_LOCKED(); |
| |
| if (next_timeout == NULL) { |
| return SYS_TIMEOUTS_SLEEPTIME_INFINITE; |
| } |
| now = sys_now(); |
| if (TIME_LESS_THAN(next_timeout->time, now)) { |
| return 0; |
| } else { |
| u32_t ret = (u32_t)(next_timeout->time - now); |
| LWIP_ASSERT("invalid sleeptime", ret <= LWIP_MAX_TIMEOUT); |
| return ret; |
| } |
| } |
| |
| #else /* LWIP_TIMERS && !LWIP_TIMERS_CUSTOM */ |
| /* Satisfy the TCP code which calls this function */ |
| void |
| tcp_timer_needed(void) |
| { |
| } |
| #endif /* LWIP_TIMERS && !LWIP_TIMERS_CUSTOM */ |