X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/8c304be359f15151ed8fe3e5ff61b0238881358d..0ef889274f104dd1e69021deec1d73ae2a1090a2:/src/debug.c diff --git a/src/debug.c b/src/debug.c index fff8d727..42a73883 100644 --- a/src/debug.c +++ b/src/debug.c @@ -2,6 +2,13 @@ #include "sha1.h" /* SHA1 is used for DEBUG DIGEST */ #include +#include + +#ifdef HAVE_BACKTRACE +#include +#include +#include +#endif /* HAVE_BACKTRACE */ /* ================================= Debugging ============================== */ @@ -91,16 +98,15 @@ void computeDatasetDigest(unsigned char *final) { while((de = dictNext(di)) != NULL) { sds key; robj *keyobj, *o; - time_t expiretime; + long long expiretime; memset(digest,0,20); /* This key-val digest */ - key = dictGetEntryKey(de); + key = dictGetKey(de); keyobj = createStringObject(key,sdslen(key)); mixDigest(digest,key,sdslen(key)); - /* Make sure the key is loaded if VM is active */ - o = lookupKeyRead(db,keyobj); + o = dictGetVal(de); aux = htonl(o->type); mixDigest(digest,&aux,sizeof(aux)); @@ -127,22 +133,57 @@ void computeDatasetDigest(unsigned char *final) { } setTypeReleaseIterator(si); } else if (o->type == REDIS_ZSET) { - zset *zs = o->ptr; - dictIterator *di = dictGetIterator(zs->dict); - dictEntry *de; - - while((de = dictNext(di)) != NULL) { - robj *eleobj = dictGetEntryKey(de); - double *score = dictGetEntryVal(de); - unsigned char eledigest[20]; - - snprintf(buf,sizeof(buf),"%.17g",*score); - memset(eledigest,0,20); - mixObjectDigest(eledigest,eleobj); - mixDigest(eledigest,buf,strlen(buf)); - xorDigest(digest,eledigest,20); + unsigned char eledigest[20]; + + if (o->encoding == REDIS_ENCODING_ZIPLIST) { + unsigned char *zl = o->ptr; + unsigned char *eptr, *sptr; + unsigned char *vstr; + unsigned int vlen; + long long vll; + double score; + + eptr = ziplistIndex(zl,0); + redisAssert(eptr != NULL); + sptr = ziplistNext(zl,eptr); + redisAssert(sptr != NULL); + + while (eptr != NULL) { + redisAssert(ziplistGet(eptr,&vstr,&vlen,&vll)); + score = zzlGetScore(sptr); + + memset(eledigest,0,20); + if (vstr != NULL) { + mixDigest(eledigest,vstr,vlen); + } else { + ll2string(buf,sizeof(buf),vll); + mixDigest(eledigest,buf,strlen(buf)); + } + + snprintf(buf,sizeof(buf),"%.17g",score); + mixDigest(eledigest,buf,strlen(buf)); + xorDigest(digest,eledigest,20); + zzlNext(zl,&eptr,&sptr); + } + } else if (o->encoding == REDIS_ENCODING_SKIPLIST) { + zset *zs = o->ptr; + dictIterator *di = dictGetIterator(zs->dict); + dictEntry *de; + + while((de = dictNext(di)) != NULL) { + robj *eleobj = dictGetKey(de); + double *score = dictGetVal(de); + + snprintf(buf,sizeof(buf),"%.17g",*score); + memset(eledigest,0,20); + mixObjectDigest(eledigest,eleobj); + mixDigest(eledigest,buf,strlen(buf)); + xorDigest(digest,eledigest,20); + } + dictReleaseIterator(di); + } else { + redisPanic("Unknown sorted set encoding"); } - dictReleaseIterator(di); } else if (o->type == REDIS_HASH) { hashTypeIterator *hi; robj *obj; @@ -177,83 +218,49 @@ void computeDatasetDigest(unsigned char *final) { void debugCommand(redisClient *c) { if (!strcasecmp(c->argv[1]->ptr,"segfault")) { *((char*)-1) = 'x'; + } else if (!strcasecmp(c->argv[1]->ptr,"assert")) { + if (c->argc >= 3) c->argv[2] = tryObjectEncoding(c->argv[2]); + redisAssertWithInfo(c,c->argv[0],1 == 2); } else if (!strcasecmp(c->argv[1]->ptr,"reload")) { - if (rdbSave(server.dbfilename) != REDIS_OK) { + if (rdbSave(server.rdb_filename) != REDIS_OK) { addReply(c,shared.err); return; } emptyDb(); - if (rdbLoad(server.dbfilename) != REDIS_OK) { - addReply(c,shared.err); + if (rdbLoad(server.rdb_filename) != REDIS_OK) { + addReplyError(c,"Error trying to load the RDB dump"); return; } redisLog(REDIS_WARNING,"DB reloaded by DEBUG RELOAD"); addReply(c,shared.ok); } else if (!strcasecmp(c->argv[1]->ptr,"loadaof")) { emptyDb(); - if (loadAppendOnlyFile(server.appendfilename) != REDIS_OK) { + if (loadAppendOnlyFile(server.aof_filename) != REDIS_OK) { addReply(c,shared.err); return; } + server.dirty = 0; /* Prevent AOF / replication */ redisLog(REDIS_WARNING,"Append Only File loaded by DEBUG LOADAOF"); addReply(c,shared.ok); } else if (!strcasecmp(c->argv[1]->ptr,"object") && c->argc == 3) { - dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr); + dictEntry *de; robj *val; + char *strenc; - if (!de) { + if ((de = dictFind(c->db->dict,c->argv[2]->ptr)) == NULL) { addReply(c,shared.nokeyerr); return; } - val = dictGetEntryVal(de); - if (!server.vm_enabled || (val->storage == REDIS_VM_MEMORY || - val->storage == REDIS_VM_SWAPPING)) { - char *strenc; - - strenc = strEncoding(val->encoding); - addReplyStatusFormat(c, - "Value at:%p refcount:%d " - "encoding:%s serializedlength:%lld " - "lru:%d lru_seconds_idle:%lu", - (void*)val, val->refcount, - strenc, (long long) rdbSavedObjectLen(val), - val->lru, estimateObjectIdleTime(val)); - } else { - vmpointer *vp = (vmpointer*) val; - addReplyStatusFormat(c, - "Value swapped at: page %llu " - "using %llu pages", - (unsigned long long) vp->page, - (unsigned long long) vp->usedpages); - } - } else if (!strcasecmp(c->argv[1]->ptr,"swapin") && c->argc == 3) { - lookupKeyRead(c->db,c->argv[2]); - addReply(c,shared.ok); - } else if (!strcasecmp(c->argv[1]->ptr,"swapout") && c->argc == 3) { - dictEntry *de = dictFind(c->db->dict,c->argv[2]->ptr); - robj *val; - vmpointer *vp; - - if (!server.vm_enabled) { - addReplyError(c,"Virtual Memory is disabled"); - return; - } - if (!de) { - addReply(c,shared.nokeyerr); - return; - } - val = dictGetEntryVal(de); - /* Swap it */ - if (val->storage != REDIS_VM_MEMORY) { - addReplyError(c,"This key is not in memory"); - } else if (val->refcount != 1) { - addReplyError(c,"Object is shared"); - } else if ((vp = vmSwapObjectBlocking(val)) != NULL) { - dictGetEntryVal(de) = vp; - addReply(c,shared.ok); - } else { - addReply(c,shared.err); - } + val = dictGetVal(de); + strenc = strEncoding(val->encoding); + + addReplyStatusFormat(c, + "Value at:%p refcount:%d " + "encoding:%s serializedlength:%lld " + "lru:%d lru_seconds_idle:%lu", + (void*)val, val->refcount, + strenc, (long long) rdbSavedObjectLen(val), + val->lru, estimateObjectIdleTime(val)); } else if (!strcasecmp(c->argv[1]->ptr,"populate") && c->argc == 3) { long keys, j; robj *key, *val; @@ -284,26 +291,463 @@ void debugCommand(redisClient *c) { d = sdscatprintf(d, "%02x",digest[j]); addReplyStatus(c,d); sdsfree(d); + } else if (!strcasecmp(c->argv[1]->ptr,"sleep") && c->argc == 3) { + double dtime = strtod(c->argv[2]->ptr,NULL); + long long utime = dtime*1000000; + + usleep(utime); + addReply(c,shared.ok); } else { addReplyError(c, "Syntax error, try DEBUG [SEGFAULT|OBJECT |SWAPIN |SWAPOUT |RELOAD]"); } } +/* =========================== Crash handling ============================== */ + void _redisAssert(char *estr, char *file, int line) { + bugReportStart(); redisLog(REDIS_WARNING,"=== ASSERTION FAILED ==="); redisLog(REDIS_WARNING,"==> %s:%d '%s' is not true",file,line,estr); #ifdef HAVE_BACKTRACE - redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)"); - *((char*)-1) = 'x'; + server.assert_failed = estr; + server.assert_file = file; + server.assert_line = line; + redisLog(REDIS_WARNING,"(forcing SIGSEGV to print the bug report.)"); #endif + *((char*)-1) = 'x'; +} + +void _redisAssertPrintClientInfo(redisClient *c) { + int j; + + bugReportStart(); + redisLog(REDIS_WARNING,"=== ASSERTION FAILED CLIENT CONTEXT ==="); + redisLog(REDIS_WARNING,"client->flags = %d", c->flags); + redisLog(REDIS_WARNING,"client->fd = %d", c->fd); + redisLog(REDIS_WARNING,"client->argc = %d", c->argc); + for (j=0; j < c->argc; j++) { + char buf[128]; + char *arg; + + if (c->argv[j]->type == REDIS_STRING && + c->argv[j]->encoding == REDIS_ENCODING_RAW) + { + arg = (char*) c->argv[j]->ptr; + } else { + snprintf(buf,sizeof(buf),"Object type: %d, encoding: %d", + c->argv[j]->type, c->argv[j]->encoding); + arg = buf; + } + redisLog(REDIS_WARNING,"client->argv[%d] = \"%s\" (refcount: %d)", + j, arg, c->argv[j]->refcount); + } +} + +void redisLogObjectDebugInfo(robj *o) { + redisLog(REDIS_WARNING,"Object type: %d", o->type); + redisLog(REDIS_WARNING,"Object encoding: %d", o->encoding); + redisLog(REDIS_WARNING,"Object refcount: %d", o->refcount); + if (o->type == REDIS_STRING && o->encoding == REDIS_ENCODING_RAW) { + redisLog(REDIS_WARNING,"Object raw string len: %d", sdslen(o->ptr)); + if (sdslen(o->ptr) < 4096) + redisLog(REDIS_WARNING,"Object raw string content: \"%s\"", (char*)o->ptr); + } else if (o->type == REDIS_LIST) { + redisLog(REDIS_WARNING,"List length: %d", (int) listTypeLength(o)); + } else if (o->type == REDIS_SET) { + redisLog(REDIS_WARNING,"Set size: %d", (int) setTypeSize(o)); + } else if (o->type == REDIS_HASH) { + redisLog(REDIS_WARNING,"Hash size: %d", (int) hashTypeLength(o)); + } else if (o->type == REDIS_ZSET) { + redisLog(REDIS_WARNING,"Sorted set size: %d", (int) zsetLength(o)); + if (o->encoding == REDIS_ENCODING_SKIPLIST) + redisLog(REDIS_WARNING,"Skiplist level: %d", (int) ((zset*)o->ptr)->zsl->level); + } +} + +void _redisAssertPrintObject(robj *o) { + bugReportStart(); + redisLog(REDIS_WARNING,"=== ASSERTION FAILED OBJECT CONTEXT ==="); + redisLogObjectDebugInfo(o); +} + +void _redisAssertWithInfo(redisClient *c, robj *o, char *estr, char *file, int line) { + if (c) _redisAssertPrintClientInfo(c); + if (o) _redisAssertPrintObject(o); + _redisAssert(estr,file,line); } void _redisPanic(char *msg, char *file, int line) { + bugReportStart(); + redisLog(REDIS_WARNING,"------------------------------------------------"); redisLog(REDIS_WARNING,"!!! Software Failure. Press left mouse button to continue"); redisLog(REDIS_WARNING,"Guru Meditation: %s #%s:%d",msg,file,line); #ifdef HAVE_BACKTRACE redisLog(REDIS_WARNING,"(forcing SIGSEGV in order to print the stack trace)"); +#endif + redisLog(REDIS_WARNING,"------------------------------------------------"); *((char*)-1) = 'x'; +} + +void bugReportStart(void) { + if (server.bug_report_start == 0) { + redisLog(REDIS_WARNING, + "\n\n=== REDIS BUG REPORT START: Cut & paste starting from here ==="); + server.bug_report_start = 1; + } +} + +#ifdef HAVE_BACKTRACE +static void *getMcontextEip(ucontext_t *uc) { +#if defined(__APPLE__) && !defined(MAC_OS_X_VERSION_10_6) + /* OSX < 10.6 */ + #if defined(__x86_64__) + return (void*) uc->uc_mcontext->__ss.__rip; + #elif defined(__i386__) + return (void*) uc->uc_mcontext->__ss.__eip; + #else + return (void*) uc->uc_mcontext->__ss.__srr0; + #endif +#elif defined(__APPLE__) && defined(MAC_OS_X_VERSION_10_6) + /* OSX >= 10.6 */ + #if defined(_STRUCT_X86_THREAD_STATE64) && !defined(__i386__) + return (void*) uc->uc_mcontext->__ss.__rip; + #else + return (void*) uc->uc_mcontext->__ss.__eip; + #endif +#elif defined(__linux__) + /* Linux */ + #if defined(__i386__) + return (void*) uc->uc_mcontext.gregs[14]; /* Linux 32 */ + #elif defined(__X86_64__) || defined(__x86_64__) + return (void*) uc->uc_mcontext.gregs[16]; /* Linux 64 */ + #elif defined(__ia64__) /* Linux IA64 */ + return (void*) uc->uc_mcontext.sc_ip; + #endif +#else + return NULL; +#endif +} + +void logStackContent(void **sp) { + int i; + for (i = 15; i >= 0; i--) { + if (sizeof(long) == 4) + redisLog(REDIS_WARNING, "(%08lx) -> %08lx", sp+i, sp[i]); + else + redisLog(REDIS_WARNING, "(%016lx) -> %016lx", sp+i, sp[i]); + } +} + +void logRegisters(ucontext_t *uc) { + redisLog(REDIS_WARNING, "--- REGISTERS"); + +/* OSX */ +#if defined(__APPLE__) && defined(MAC_OS_X_VERSION_10_6) + /* OSX AMD64 */ + #if defined(_STRUCT_X86_THREAD_STATE64) && !defined(__i386__) + redisLog(REDIS_WARNING, + "\n" + "RAX:%016lx RBX:%016lx\nRCX:%016lx RDX:%016lx\n" + "RDI:%016lx RSI:%016lx\nRBP:%016lx RSP:%016lx\n" + "R8 :%016lx R9 :%016lx\nR10:%016lx R11:%016lx\n" + "R12:%016lx R13:%016lx\nR14:%016lx R15:%016lx\n" + "RIP:%016lx EFL:%016lx\nCS :%016lx FS:%016lx GS:%016lx", + uc->uc_mcontext->__ss.__rax, + uc->uc_mcontext->__ss.__rbx, + uc->uc_mcontext->__ss.__rcx, + uc->uc_mcontext->__ss.__rdx, + uc->uc_mcontext->__ss.__rdi, + uc->uc_mcontext->__ss.__rsi, + uc->uc_mcontext->__ss.__rbp, + uc->uc_mcontext->__ss.__rsp, + uc->uc_mcontext->__ss.__r8, + uc->uc_mcontext->__ss.__r9, + uc->uc_mcontext->__ss.__r10, + uc->uc_mcontext->__ss.__r11, + uc->uc_mcontext->__ss.__r12, + uc->uc_mcontext->__ss.__r13, + uc->uc_mcontext->__ss.__r14, + uc->uc_mcontext->__ss.__r15, + uc->uc_mcontext->__ss.__rip, + uc->uc_mcontext->__ss.__rflags, + uc->uc_mcontext->__ss.__cs, + uc->uc_mcontext->__ss.__fs, + uc->uc_mcontext->__ss.__gs + ); + logStackContent((void**)uc->uc_mcontext->__ss.__rsp); + #else + /* OSX x86 */ + redisLog(REDIS_WARNING, + "\n" + "EAX:%08lx EBX:%08lx ECX:%08lx EDX:%08lx\n" + "EDI:%08lx ESI:%08lx EBP:%08lx ESP:%08lx\n" + "SS:%08lx EFL:%08lx EIP:%08lx CS :%08lx\n" + "DS:%08lx ES:%08lx FS :%08lx GS :%08lx", + uc->uc_mcontext->__ss.__eax, + uc->uc_mcontext->__ss.__ebx, + uc->uc_mcontext->__ss.__ecx, + uc->uc_mcontext->__ss.__edx, + uc->uc_mcontext->__ss.__edi, + uc->uc_mcontext->__ss.__esi, + uc->uc_mcontext->__ss.__ebp, + uc->uc_mcontext->__ss.__esp, + uc->uc_mcontext->__ss.__ss, + uc->uc_mcontext->__ss.__eflags, + uc->uc_mcontext->__ss.__eip, + uc->uc_mcontext->__ss.__cs, + uc->uc_mcontext->__ss.__ds, + uc->uc_mcontext->__ss.__es, + uc->uc_mcontext->__ss.__fs, + uc->uc_mcontext->__ss.__gs + ); + logStackContent((void**)uc->uc_mcontext->__ss.__esp); + #endif +/* Linux */ +#elif defined(__linux__) + /* Linux x86 */ + #if defined(__i386__) + redisLog(REDIS_WARNING, + "\n" + "EAX:%08lx EBX:%08lx ECX:%08lx EDX:%08lx\n" + "EDI:%08lx ESI:%08lx EBP:%08lx ESP:%08lx\n" + "SS :%08lx EFL:%08lx EIP:%08lx CS:%08lx\n" + "DS :%08lx ES :%08lx FS :%08lx GS:%08lx", + uc->uc_mcontext.gregs[11], + uc->uc_mcontext.gregs[8], + uc->uc_mcontext.gregs[10], + uc->uc_mcontext.gregs[9], + uc->uc_mcontext.gregs[4], + uc->uc_mcontext.gregs[5], + uc->uc_mcontext.gregs[6], + uc->uc_mcontext.gregs[7], + uc->uc_mcontext.gregs[18], + uc->uc_mcontext.gregs[17], + uc->uc_mcontext.gregs[14], + uc->uc_mcontext.gregs[15], + uc->uc_mcontext.gregs[3], + uc->uc_mcontext.gregs[2], + uc->uc_mcontext.gregs[1], + uc->uc_mcontext.gregs[0] + ); + logStackContent((void**)uc->uc_mcontext.gregs[7]); + #elif defined(__X86_64__) || defined(__x86_64__) + /* Linux AMD64 */ + redisLog(REDIS_WARNING, + "\n" + "RAX:%016lx RBX:%016lx\nRCX:%016lx RDX:%016lx\n" + "RDI:%016lx RSI:%016lx\nRBP:%016lx RSP:%016lx\n" + "R8 :%016lx R9 :%016lx\nR10:%016lx R11:%016lx\n" + "R12:%016lx R13:%016lx\nR14:%016lx R15:%016lx\n" + "RIP:%016lx EFL:%016lx\nCSGSFS:%016lx", + uc->uc_mcontext.gregs[13], + uc->uc_mcontext.gregs[11], + uc->uc_mcontext.gregs[14], + uc->uc_mcontext.gregs[12], + uc->uc_mcontext.gregs[8], + uc->uc_mcontext.gregs[9], + uc->uc_mcontext.gregs[10], + uc->uc_mcontext.gregs[15], + uc->uc_mcontext.gregs[0], + uc->uc_mcontext.gregs[1], + uc->uc_mcontext.gregs[2], + uc->uc_mcontext.gregs[3], + uc->uc_mcontext.gregs[4], + uc->uc_mcontext.gregs[5], + uc->uc_mcontext.gregs[6], + uc->uc_mcontext.gregs[7], + uc->uc_mcontext.gregs[16], + uc->uc_mcontext.gregs[17], + uc->uc_mcontext.gregs[18] + ); + logStackContent((void**)uc->uc_mcontext.gregs[15]); + #endif +#else + redisLog(REDIS_WARNING, + " Dumping of registers not supported for this OS/arch"); +#endif +} + +/* Logs the stack trace using the backtrace() call. This function is designed + * to be called from signal handlers safely. */ +void logStackTrace(ucontext_t *uc) { + void *trace[100]; + int trace_size = 0, fd; + + /* Open the log file in append mode. */ + fd = server.logfile ? + open(server.logfile, O_APPEND|O_CREAT|O_WRONLY, 0644) : + STDOUT_FILENO; + if (fd == -1) return; + + /* Generate the stack trace */ + trace_size = backtrace(trace, 100); + + /* overwrite sigaction with caller's address */ + if (getMcontextEip(uc) != NULL) + trace[1] = getMcontextEip(uc); + + /* Write symbols to log file */ + backtrace_symbols_fd(trace, trace_size, fd); + + /* Cleanup */ + if (server.logfile) close(fd); +} + +/* Log information about the "current" client, that is, the client that is + * currently being served by Redis. May be NULL if Redis is not serving a + * client right now. */ +void logCurrentClient(void) { + if (server.current_client == NULL) return; + + redisClient *cc = server.current_client; + sds client; + int j; + + redisLog(REDIS_WARNING, "--- CURRENT CLIENT INFO"); + client = getClientInfoString(cc); + redisLog(REDIS_WARNING,"client: %s", client); + sdsfree(client); + for (j = 0; j < cc->argc; j++) { + robj *decoded; + + decoded = getDecodedObject(cc->argv[j]); + redisLog(REDIS_WARNING,"argv[%d]: '%s'", j, (char*)decoded->ptr); + decrRefCount(decoded); + } + /* Check if the first argument, usually a key, is found inside the + * selected DB, and if so print info about the associated object. */ + if (cc->argc >= 1) { + robj *val, *key; + dictEntry *de; + + key = getDecodedObject(cc->argv[1]); + de = dictFind(cc->db->dict, key->ptr); + if (de) { + val = dictGetVal(de); + redisLog(REDIS_WARNING,"key '%s' found in DB containing the following object:", key->ptr); + redisLogObjectDebugInfo(val); + } + decrRefCount(key); + } +} + +void sigsegvHandler(int sig, siginfo_t *info, void *secret) { + ucontext_t *uc = (ucontext_t*) secret; + sds infostring, clients; + struct sigaction act; + REDIS_NOTUSED(info); + + bugReportStart(); + redisLog(REDIS_WARNING, + " Redis %s crashed by signal: %d", REDIS_VERSION, sig); + redisLog(REDIS_WARNING, + " Failed assertion: %s (%s:%d)", server.assert_failed, + server.assert_file, server.assert_line); + + /* Log the stack trace */ + redisLog(REDIS_WARNING, "--- STACK TRACE"); + logStackTrace(uc); + + /* Log INFO and CLIENT LIST */ + redisLog(REDIS_WARNING, "--- INFO OUTPUT"); + infostring = genRedisInfoString("all"); + infostring = sdscatprintf(infostring, "hash_init_value: %u\n", + dictGetHashFunctionSeed()); + redisLogRaw(REDIS_WARNING, infostring); + redisLog(REDIS_WARNING, "--- CLIENT LIST OUTPUT"); + clients = getAllClientsInfoString(); + redisLogRaw(REDIS_WARNING, clients); + sdsfree(infostring); + sdsfree(clients); + + /* Log the current client */ + logCurrentClient(); + + /* Log dump of processor registers */ + logRegisters(uc); + + redisLog(REDIS_WARNING, +"\n=== REDIS BUG REPORT END. Make sure to include from START to END. ===\n\n" +" Please report the crash opening an issue on github:\n\n" +" http://github.com/antirez/redis/issues\n\n" +" Suspect RAM error? Use redis-server --test-memory to veryfy it.\n\n" +); + /* free(messages); Don't call free() with possibly corrupted memory. */ + if (server.daemonize) unlink(server.pidfile); + + /* Make sure we exit with the right signal at the end. So for instance + * the core will be dumped if enabled. */ + sigemptyset (&act.sa_mask); + act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_RESETHAND; + act.sa_handler = SIG_DFL; + sigaction (sig, &act, NULL); + kill(getpid(),sig); +} +#endif /* HAVE_BACKTRACE */ + +/* =========================== Software Watchdog ============================ */ +#include + +void watchdogSignalHandler(int sig, siginfo_t *info, void *secret) { +#ifdef HAVE_BACKTRACE + ucontext_t *uc = (ucontext_t*) secret; +#endif + REDIS_NOTUSED(info); + REDIS_NOTUSED(sig); + + redisLogFromHandler(REDIS_WARNING,"\n--- WATCHDOG TIMER EXPIRED ---"); +#ifdef HAVE_BACKTRACE + logStackTrace(uc); +#else + redisLogFromHandler(REDIS_WARNING,"Sorry: no support for backtrace()."); #endif + redisLogFromHandler(REDIS_WARNING,"--------\n"); +} + +/* Schedule a SIGALRM delivery after the specified period in milliseconds. + * If a timer is already scheduled, this function will re-schedule it to the + * specified time. If period is 0 the current timer is disabled. */ +void watchdogScheduleSignal(int period) { + struct itimerval it; + + /* Will stop the timer if period is 0. */ + it.it_value.tv_sec = period/1000; + it.it_value.tv_usec = (period%1000)*1000; + /* Don't automatically restart. */ + it.it_interval.tv_sec = 0; + it.it_interval.tv_usec = 0; + setitimer(ITIMER_REAL, &it, NULL); +} + +/* Enable the software watchdong with the specified period in milliseconds. */ +void enableWatchdog(int period) { + if (server.watchdog_period == 0) { + struct sigaction act; + + /* Watchdog was actually disabled, so we have to setup the signal + * handler. */ + sigemptyset(&act.sa_mask); + act.sa_flags = SA_NODEFER | SA_ONSTACK | SA_SIGINFO; + act.sa_sigaction = watchdogSignalHandler; + sigaction(SIGALRM, &act, NULL); + } + if (period < 200) period = 200; /* We don't accept periods < 200 ms. */ + watchdogScheduleSignal(period); /* Adjust the current timer. */ + server.watchdog_period = period; +} + +/* Disable the software watchdog. */ +void disableWatchdog(void) { + struct sigaction act; + if (server.watchdog_period == 0) return; /* Already disabled. */ + watchdogScheduleSignal(0); /* Stop the current timer. */ + + /* Set the signal handler to SIG_IGN, this will also remove pending + * signals from the queue. */ + sigemptyset(&act.sa_mask); + act.sa_flags = 0; + act.sa_handler = SIG_IGN; + sigaction(SIGALRM, &act, NULL); + server.watchdog_period = 0; }