| /* |
| * Copyright (C) 2012-2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #define LOG_TAG "DEBUG" |
| |
| #include <dirent.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <signal.h> |
| #include <stddef.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <time.h> |
| #include <sys/ptrace.h> |
| #include <sys/stat.h> |
| |
| #include <memory> |
| #include <string> |
| |
| #include <private/android_filesystem_config.h> |
| |
| #include <android-base/stringprintf.h> |
| #include <cutils/properties.h> |
| #include <log/log.h> |
| #include <log/logger.h> |
| #include <log/logprint.h> |
| |
| #include <backtrace/Backtrace.h> |
| #include <backtrace/BacktraceMap.h> |
| |
| #include <selinux/android.h> |
| |
| #include "backtrace.h" |
| #include "elf_utils.h" |
| #include "machine.h" |
| #include "tombstone.h" |
| |
| #define STACK_WORDS 16 |
| |
| #define MAX_TOMBSTONES 10 |
| #define TOMBSTONE_DIR "/data/tombstones" |
| #define TOMBSTONE_TEMPLATE (TOMBSTONE_DIR"/tombstone_%02d") |
| |
| static bool signal_has_si_addr(int sig) { |
| switch (sig) { |
| case SIGBUS: |
| case SIGFPE: |
| case SIGILL: |
| case SIGSEGV: |
| case SIGTRAP: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static const char* get_signame(int sig) { |
| switch(sig) { |
| case SIGABRT: return "SIGABRT"; |
| case SIGBUS: return "SIGBUS"; |
| case SIGFPE: return "SIGFPE"; |
| case SIGILL: return "SIGILL"; |
| case SIGSEGV: return "SIGSEGV"; |
| #if defined(SIGSTKFLT) |
| case SIGSTKFLT: return "SIGSTKFLT"; |
| #endif |
| case SIGSTOP: return "SIGSTOP"; |
| case SIGTRAP: return "SIGTRAP"; |
| default: return "?"; |
| } |
| } |
| |
| static const char* get_sigcode(int signo, int code) { |
| // Try the signal-specific codes... |
| switch (signo) { |
| case SIGILL: |
| switch (code) { |
| case ILL_ILLOPC: return "ILL_ILLOPC"; |
| case ILL_ILLOPN: return "ILL_ILLOPN"; |
| case ILL_ILLADR: return "ILL_ILLADR"; |
| case ILL_ILLTRP: return "ILL_ILLTRP"; |
| case ILL_PRVOPC: return "ILL_PRVOPC"; |
| case ILL_PRVREG: return "ILL_PRVREG"; |
| case ILL_COPROC: return "ILL_COPROC"; |
| case ILL_BADSTK: return "ILL_BADSTK"; |
| } |
| static_assert(NSIGILL == ILL_BADSTK, "missing ILL_* si_code"); |
| break; |
| case SIGBUS: |
| switch (code) { |
| case BUS_ADRALN: return "BUS_ADRALN"; |
| case BUS_ADRERR: return "BUS_ADRERR"; |
| case BUS_OBJERR: return "BUS_OBJERR"; |
| case BUS_MCEERR_AR: return "BUS_MCEERR_AR"; |
| case BUS_MCEERR_AO: return "BUS_MCEERR_AO"; |
| } |
| static_assert(NSIGBUS == BUS_MCEERR_AO, "missing BUS_* si_code"); |
| break; |
| case SIGFPE: |
| switch (code) { |
| case FPE_INTDIV: return "FPE_INTDIV"; |
| case FPE_INTOVF: return "FPE_INTOVF"; |
| case FPE_FLTDIV: return "FPE_FLTDIV"; |
| case FPE_FLTOVF: return "FPE_FLTOVF"; |
| case FPE_FLTUND: return "FPE_FLTUND"; |
| case FPE_FLTRES: return "FPE_FLTRES"; |
| case FPE_FLTINV: return "FPE_FLTINV"; |
| case FPE_FLTSUB: return "FPE_FLTSUB"; |
| } |
| static_assert(NSIGFPE == FPE_FLTSUB, "missing FPE_* si_code"); |
| break; |
| case SIGSEGV: |
| switch (code) { |
| case SEGV_MAPERR: return "SEGV_MAPERR"; |
| case SEGV_ACCERR: return "SEGV_ACCERR"; |
| #if defined(SEGV_BNDERR) |
| case SEGV_BNDERR: return "SEGV_BNDERR"; |
| #endif |
| } |
| #if defined(SEGV_BNDERR) |
| static_assert(NSIGSEGV == SEGV_BNDERR, "missing SEGV_* si_code"); |
| #else |
| static_assert(NSIGSEGV == SEGV_ACCERR, "missing SEGV_* si_code"); |
| #endif |
| break; |
| case SIGTRAP: |
| switch (code) { |
| case TRAP_BRKPT: return "TRAP_BRKPT"; |
| case TRAP_TRACE: return "TRAP_TRACE"; |
| case TRAP_BRANCH: return "TRAP_BRANCH"; |
| case TRAP_HWBKPT: return "TRAP_HWBKPT"; |
| } |
| static_assert(NSIGTRAP == TRAP_HWBKPT, "missing TRAP_* si_code"); |
| break; |
| } |
| // Then the other codes... |
| switch (code) { |
| case SI_USER: return "SI_USER"; |
| case SI_KERNEL: return "SI_KERNEL"; |
| case SI_QUEUE: return "SI_QUEUE"; |
| case SI_TIMER: return "SI_TIMER"; |
| case SI_MESGQ: return "SI_MESGQ"; |
| case SI_ASYNCIO: return "SI_ASYNCIO"; |
| case SI_SIGIO: return "SI_SIGIO"; |
| case SI_TKILL: return "SI_TKILL"; |
| case SI_DETHREAD: return "SI_DETHREAD"; |
| } |
| // Then give up... |
| return "?"; |
| } |
| |
| static void dump_header_info(log_t* log) { |
| char fingerprint[PROPERTY_VALUE_MAX]; |
| char revision[PROPERTY_VALUE_MAX]; |
| |
| property_get("ro.build.fingerprint", fingerprint, "unknown"); |
| property_get("ro.revision", revision, "unknown"); |
| |
| _LOG(log, logtype::HEADER, "Build fingerprint: '%s'\n", fingerprint); |
| _LOG(log, logtype::HEADER, "Revision: '%s'\n", revision); |
| _LOG(log, logtype::HEADER, "ABI: '%s'\n", ABI_STRING); |
| } |
| |
| static void dump_signal_info(log_t* log, pid_t tid, int signal, int si_code) { |
| siginfo_t si; |
| memset(&si, 0, sizeof(si)); |
| if (ptrace(PTRACE_GETSIGINFO, tid, 0, &si) == -1) { |
| ALOGE("cannot get siginfo: %s\n", strerror(errno)); |
| return; |
| } |
| |
| // bionic has to re-raise some signals, which overwrites the si_code with SI_TKILL. |
| si.si_code = si_code; |
| |
| char addr_desc[32]; // ", fault addr 0x1234" |
| if (signal_has_si_addr(signal)) { |
| snprintf(addr_desc, sizeof(addr_desc), "%p", si.si_addr); |
| } else { |
| snprintf(addr_desc, sizeof(addr_desc), "--------"); |
| } |
| |
| _LOG(log, logtype::HEADER, "signal %d (%s), code %d (%s), fault addr %s\n", |
| signal, get_signame(signal), si.si_code, get_sigcode(signal, si.si_code), addr_desc); |
| } |
| |
| static void dump_thread_info(log_t* log, pid_t pid, pid_t tid) { |
| char path[64]; |
| char threadnamebuf[1024]; |
| char* threadname = nullptr; |
| FILE *fp; |
| |
| snprintf(path, sizeof(path), "/proc/%d/comm", tid); |
| if ((fp = fopen(path, "r"))) { |
| threadname = fgets(threadnamebuf, sizeof(threadnamebuf), fp); |
| fclose(fp); |
| if (threadname) { |
| size_t len = strlen(threadname); |
| if (len && threadname[len - 1] == '\n') { |
| threadname[len - 1] = '\0'; |
| } |
| } |
| } |
| // Blacklist logd, logd.reader, logd.writer, logd.auditd, logd.control ... |
| static const char logd[] = "logd"; |
| if (threadname != nullptr && !strncmp(threadname, logd, sizeof(logd) - 1) |
| && (!threadname[sizeof(logd) - 1] || (threadname[sizeof(logd) - 1] == '.'))) { |
| log->should_retrieve_logcat = false; |
| } |
| |
| char procnamebuf[1024]; |
| char* procname = nullptr; |
| |
| snprintf(path, sizeof(path), "/proc/%d/cmdline", pid); |
| if ((fp = fopen(path, "r"))) { |
| procname = fgets(procnamebuf, sizeof(procnamebuf), fp); |
| fclose(fp); |
| } |
| |
| _LOG(log, logtype::HEADER, "pid: %d, tid: %d, name: %s >>> %s <<<\n", pid, tid, |
| threadname ? threadname : "UNKNOWN", procname ? procname : "UNKNOWN"); |
| } |
| |
| static void dump_stack_segment( |
| Backtrace* backtrace, log_t* log, uintptr_t* sp, size_t words, int label) { |
| // Read the data all at once. |
| word_t stack_data[words]; |
| size_t bytes_read = backtrace->Read(*sp, reinterpret_cast<uint8_t*>(&stack_data[0]), sizeof(word_t) * words); |
| words = bytes_read / sizeof(word_t); |
| std::string line; |
| for (size_t i = 0; i < words; i++) { |
| line = " "; |
| if (i == 0 && label >= 0) { |
| // Print the label once. |
| line += android::base::StringPrintf("#%02d ", label); |
| } else { |
| line += " "; |
| } |
| line += android::base::StringPrintf("%" PRIPTR " %" PRIPTR, *sp, stack_data[i]); |
| |
| backtrace_map_t map; |
| backtrace->FillInMap(stack_data[i], &map); |
| if (BacktraceMap::IsValid(map) && !map.name.empty()) { |
| line += " " + map.name; |
| uintptr_t offset = 0; |
| std::string func_name(backtrace->GetFunctionName(stack_data[i], &offset)); |
| if (!func_name.empty()) { |
| line += " (" + func_name; |
| if (offset) { |
| line += android::base::StringPrintf("+%" PRIuPTR, offset); |
| } |
| line += ')'; |
| } |
| } |
| _LOG(log, logtype::STACK, "%s\n", line.c_str()); |
| |
| *sp += sizeof(word_t); |
| } |
| } |
| |
| static void dump_stack(Backtrace* backtrace, log_t* log) { |
| size_t first = 0, last; |
| for (size_t i = 0; i < backtrace->NumFrames(); i++) { |
| const backtrace_frame_data_t* frame = backtrace->GetFrame(i); |
| if (frame->sp) { |
| if (!first) { |
| first = i+1; |
| } |
| last = i; |
| } |
| } |
| if (!first) { |
| return; |
| } |
| first--; |
| |
| // Dump a few words before the first frame. |
| word_t sp = backtrace->GetFrame(first)->sp - STACK_WORDS * sizeof(word_t); |
| dump_stack_segment(backtrace, log, &sp, STACK_WORDS, -1); |
| |
| // Dump a few words from all successive frames. |
| // Only log the first 3 frames, put the rest in the tombstone. |
| for (size_t i = first; i <= last; i++) { |
| const backtrace_frame_data_t* frame = backtrace->GetFrame(i); |
| if (sp != frame->sp) { |
| _LOG(log, logtype::STACK, " ........ ........\n"); |
| sp = frame->sp; |
| } |
| if (i == last) { |
| dump_stack_segment(backtrace, log, &sp, STACK_WORDS, i); |
| if (sp < frame->sp + frame->stack_size) { |
| _LOG(log, logtype::STACK, " ........ ........\n"); |
| } |
| } else { |
| size_t words = frame->stack_size / sizeof(word_t); |
| if (words == 0) { |
| words = 1; |
| } else if (words > STACK_WORDS) { |
| words = STACK_WORDS; |
| } |
| dump_stack_segment(backtrace, log, &sp, words, i); |
| } |
| } |
| } |
| |
| static std::string get_addr_string(uintptr_t addr) { |
| std::string addr_str; |
| #if defined(__LP64__) |
| addr_str = android::base::StringPrintf("%08x'%08x", |
| static_cast<uint32_t>(addr >> 32), |
| static_cast<uint32_t>(addr & 0xffffffff)); |
| #else |
| addr_str = android::base::StringPrintf("%08x", addr); |
| #endif |
| return addr_str; |
| } |
| |
| static void dump_abort_message(Backtrace* backtrace, log_t* log, uintptr_t address) { |
| if (address == 0) { |
| return; |
| } |
| |
| address += sizeof(size_t); // Skip the buffer length. |
| |
| char msg[512]; |
| memset(msg, 0, sizeof(msg)); |
| char* p = &msg[0]; |
| while (p < &msg[sizeof(msg)]) { |
| word_t data; |
| size_t len = sizeof(word_t); |
| if (!backtrace->ReadWord(address, &data)) { |
| break; |
| } |
| address += sizeof(word_t); |
| |
| while (len > 0 && (*p++ = (data >> (sizeof(word_t) - len) * 8) & 0xff) != 0) { |
| len--; |
| } |
| } |
| msg[sizeof(msg) - 1] = '\0'; |
| |
| _LOG(log, logtype::HEADER, "Abort message: '%s'\n", msg); |
| } |
| |
| static void dump_all_maps(Backtrace* backtrace, BacktraceMap* map, log_t* log, pid_t tid) { |
| bool print_fault_address_marker = false; |
| uintptr_t addr = 0; |
| siginfo_t si; |
| memset(&si, 0, sizeof(si)); |
| if (ptrace(PTRACE_GETSIGINFO, tid, 0, &si) != -1) { |
| print_fault_address_marker = signal_has_si_addr(si.si_signo); |
| addr = reinterpret_cast<uintptr_t>(si.si_addr); |
| } else { |
| ALOGE("Cannot get siginfo for %d: %s\n", tid, strerror(errno)); |
| } |
| |
| ScopedBacktraceMapIteratorLock lock(map); |
| _LOG(log, logtype::MAPS, "\n"); |
| if (!print_fault_address_marker) { |
| _LOG(log, logtype::MAPS, "memory map:\n"); |
| } else { |
| _LOG(log, logtype::MAPS, "memory map: (fault address prefixed with --->)\n"); |
| if (map->begin() != map->end() && addr < map->begin()->start) { |
| _LOG(log, logtype::MAPS, "--->Fault address falls at %s before any mapped regions\n", |
| get_addr_string(addr).c_str()); |
| print_fault_address_marker = false; |
| } |
| } |
| |
| std::string line; |
| for (BacktraceMap::const_iterator it = map->begin(); it != map->end(); ++it) { |
| line = " "; |
| if (print_fault_address_marker) { |
| if (addr < it->start) { |
| _LOG(log, logtype::MAPS, "--->Fault address falls at %s between mapped regions\n", |
| get_addr_string(addr).c_str()); |
| print_fault_address_marker = false; |
| } else if (addr >= it->start && addr < it->end) { |
| line = "--->"; |
| print_fault_address_marker = false; |
| } |
| } |
| line += get_addr_string(it->start) + '-' + get_addr_string(it->end - 1) + ' '; |
| if (it->flags & PROT_READ) { |
| line += 'r'; |
| } else { |
| line += '-'; |
| } |
| if (it->flags & PROT_WRITE) { |
| line += 'w'; |
| } else { |
| line += '-'; |
| } |
| if (it->flags & PROT_EXEC) { |
| line += 'x'; |
| } else { |
| line += '-'; |
| } |
| line += android::base::StringPrintf(" %8" PRIxPTR " %8" PRIxPTR, |
| it->offset, it->end - it->start); |
| bool space_needed = true; |
| if (it->name.length() > 0) { |
| space_needed = false; |
| line += " " + it->name; |
| std::string build_id; |
| if ((it->flags & PROT_READ) && elf_get_build_id(backtrace, it->start, &build_id)) { |
| line += " (BuildId: " + build_id + ")"; |
| } |
| } |
| if (it->load_base != 0) { |
| if (space_needed) { |
| line += ' '; |
| } |
| line += android::base::StringPrintf(" (load base 0x%" PRIxPTR ")", it->load_base); |
| } |
| _LOG(log, logtype::MAPS, "%s\n", line.c_str()); |
| } |
| if (print_fault_address_marker) { |
| _LOG(log, logtype::MAPS, "--->Fault address falls at %s after any mapped regions\n", |
| get_addr_string(addr).c_str()); |
| } |
| } |
| |
| static void dump_backtrace_and_stack(Backtrace* backtrace, log_t* log) { |
| if (backtrace->NumFrames()) { |
| _LOG(log, logtype::BACKTRACE, "\nbacktrace:\n"); |
| dump_backtrace_to_log(backtrace, log, " "); |
| |
| _LOG(log, logtype::STACK, "\nstack:\n"); |
| dump_stack(backtrace, log); |
| } |
| } |
| |
| static void dump_thread(log_t* log, pid_t pid, pid_t tid, BacktraceMap* map, int signal, |
| int si_code, uintptr_t abort_msg_address, bool primary_thread) { |
| log->current_tid = tid; |
| if (!primary_thread) { |
| _LOG(log, logtype::THREAD, "--- --- --- --- --- --- --- --- --- --- --- --- --- --- --- ---\n"); |
| } |
| dump_thread_info(log, pid, tid); |
| |
| if (signal) { |
| dump_signal_info(log, tid, signal, si_code); |
| } |
| |
| std::unique_ptr<Backtrace> backtrace(Backtrace::Create(pid, tid, map)); |
| if (primary_thread) { |
| dump_abort_message(backtrace.get(), log, abort_msg_address); |
| } |
| dump_registers(log, tid); |
| if (backtrace->Unwind(0)) { |
| dump_backtrace_and_stack(backtrace.get(), log); |
| } else { |
| ALOGE("Unwind failed: pid = %d, tid = %d", pid, tid); |
| } |
| |
| if (primary_thread) { |
| dump_memory_and_code(log, backtrace.get()); |
| if (map) { |
| dump_all_maps(backtrace.get(), map, log, tid); |
| } |
| } |
| |
| log->current_tid = log->crashed_tid; |
| } |
| |
| // Reads the contents of the specified log device, filters out the entries |
| // that don't match the specified pid, and writes them to the tombstone file. |
| // |
| // If "tail" is non-zero, log the last "tail" number of lines. |
| static EventTagMap* g_eventTagMap = NULL; |
| |
| static void dump_log_file( |
| log_t* log, pid_t pid, const char* filename, unsigned int tail) { |
| bool first = true; |
| struct logger_list* logger_list; |
| |
| if (!log->should_retrieve_logcat) { |
| return; |
| } |
| |
| logger_list = android_logger_list_open( |
| android_name_to_log_id(filename), ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK, tail, pid); |
| |
| if (!logger_list) { |
| ALOGE("Unable to open %s: %s\n", filename, strerror(errno)); |
| return; |
| } |
| |
| struct log_msg log_entry; |
| |
| while (true) { |
| ssize_t actual = android_logger_list_read(logger_list, &log_entry); |
| struct logger_entry* entry; |
| |
| if (actual < 0) { |
| if (actual == -EINTR) { |
| // interrupted by signal, retry |
| continue; |
| } else if (actual == -EAGAIN) { |
| // non-blocking EOF; we're done |
| break; |
| } else { |
| ALOGE("Error while reading log: %s\n", strerror(-actual)); |
| break; |
| } |
| } else if (actual == 0) { |
| ALOGE("Got zero bytes while reading log: %s\n", strerror(errno)); |
| break; |
| } |
| |
| // NOTE: if you ALOGV something here, this will spin forever, |
| // because you will be writing as fast as you're reading. Any |
| // high-frequency debug diagnostics should just be written to |
| // the tombstone file. |
| |
| entry = &log_entry.entry_v1; |
| |
| if (first) { |
| _LOG(log, logtype::LOGS, "--------- %slog %s\n", |
| tail ? "tail end of " : "", filename); |
| first = false; |
| } |
| |
| // Msg format is: <priority:1><tag:N>\0<message:N>\0 |
| // |
| // We want to display it in the same format as "logcat -v threadtime" |
| // (although in this case the pid is redundant). |
| static const char* kPrioChars = "!.VDIWEFS"; |
| unsigned hdr_size = log_entry.entry.hdr_size; |
| if (!hdr_size) { |
| hdr_size = sizeof(log_entry.entry_v1); |
| } |
| char* msg = reinterpret_cast<char*>(log_entry.buf) + hdr_size; |
| |
| char timeBuf[32]; |
| time_t sec = static_cast<time_t>(entry->sec); |
| struct tm tmBuf; |
| struct tm* ptm; |
| ptm = localtime_r(&sec, &tmBuf); |
| strftime(timeBuf, sizeof(timeBuf), "%m-%d %H:%M:%S", ptm); |
| |
| if (log_entry.id() == LOG_ID_EVENTS) { |
| if (!g_eventTagMap) { |
| g_eventTagMap = android_openEventTagMap(EVENT_TAG_MAP_FILE); |
| } |
| AndroidLogEntry e; |
| char buf[512]; |
| android_log_processBinaryLogBuffer(entry, &e, g_eventTagMap, buf, sizeof(buf)); |
| _LOG(log, logtype::LOGS, "%s.%03d %5d %5d %c %-8s: %s\n", |
| timeBuf, entry->nsec / 1000000, entry->pid, entry->tid, |
| 'I', e.tag, e.message); |
| continue; |
| } |
| |
| unsigned char prio = msg[0]; |
| char* tag = msg + 1; |
| msg = tag + strlen(tag) + 1; |
| |
| // consume any trailing newlines |
| char* nl = msg + strlen(msg) - 1; |
| while (nl >= msg && *nl == '\n') { |
| *nl-- = '\0'; |
| } |
| |
| char prioChar = (prio < strlen(kPrioChars) ? kPrioChars[prio] : '?'); |
| |
| // Look for line breaks ('\n') and display each text line |
| // on a separate line, prefixed with the header, like logcat does. |
| do { |
| nl = strchr(msg, '\n'); |
| if (nl) { |
| *nl = '\0'; |
| ++nl; |
| } |
| |
| _LOG(log, logtype::LOGS, "%s.%03d %5d %5d %c %-8s: %s\n", |
| timeBuf, entry->nsec / 1000000, entry->pid, entry->tid, |
| prioChar, tag, msg); |
| } while ((msg = nl)); |
| } |
| |
| android_logger_list_free(logger_list); |
| } |
| |
| // Dumps the logs generated by the specified pid to the tombstone, from both |
| // "system" and "main" log devices. Ideally we'd interleave the output. |
| static void dump_logs(log_t* log, pid_t pid, unsigned int tail) { |
| dump_log_file(log, pid, "system", tail); |
| dump_log_file(log, pid, "main", tail); |
| } |
| |
| // Dumps all information about the specified pid to the tombstone. |
| static void dump_crash(log_t* log, BacktraceMap* map, pid_t pid, pid_t tid, |
| const std::set<pid_t>& siblings, int signal, int si_code, |
| uintptr_t abort_msg_address) { |
| // don't copy log messages to tombstone unless this is a dev device |
| char value[PROPERTY_VALUE_MAX]; |
| property_get("ro.debuggable", value, "0"); |
| bool want_logs = (value[0] == '1'); |
| |
| _LOG(log, logtype::HEADER, |
| "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n"); |
| dump_header_info(log); |
| dump_thread(log, pid, tid, map, signal, si_code, abort_msg_address, true); |
| if (want_logs) { |
| dump_logs(log, pid, 5); |
| } |
| |
| if (!siblings.empty()) { |
| for (pid_t sibling : siblings) { |
| dump_thread(log, pid, sibling, map, 0, 0, 0, false); |
| } |
| } |
| |
| if (want_logs) { |
| dump_logs(log, pid, 0); |
| } |
| } |
| |
| // open_tombstone - find an available tombstone slot, if any, of the |
| // form tombstone_XX where XX is 00 to MAX_TOMBSTONES-1, inclusive. If no |
| // file is available, we reuse the least-recently-modified file. |
| int open_tombstone(std::string* out_path) { |
| // In a single pass, find an available slot and, in case none |
| // exist, find and record the least-recently-modified file. |
| char path[128]; |
| int fd = -1; |
| int oldest = -1; |
| struct stat oldest_sb; |
| for (int i = 0; i < MAX_TOMBSTONES; i++) { |
| snprintf(path, sizeof(path), TOMBSTONE_TEMPLATE, i); |
| |
| struct stat sb; |
| if (stat(path, &sb) == 0) { |
| if (oldest < 0 || sb.st_mtime < oldest_sb.st_mtime) { |
| oldest = i; |
| oldest_sb.st_mtime = sb.st_mtime; |
| } |
| continue; |
| } |
| if (errno != ENOENT) continue; |
| |
| fd = open(path, O_CREAT | O_EXCL | O_WRONLY | O_NOFOLLOW | O_CLOEXEC, 0600); |
| if (fd < 0) continue; // raced ? |
| |
| if (out_path) { |
| *out_path = path; |
| } |
| fchown(fd, AID_SYSTEM, AID_SYSTEM); |
| return fd; |
| } |
| |
| if (oldest < 0) { |
| ALOGE("debuggerd: failed to find a valid tombstone, default to using tombstone 0.\n"); |
| oldest = 0; |
| } |
| |
| // we didn't find an available file, so we clobber the oldest one |
| snprintf(path, sizeof(path), TOMBSTONE_TEMPLATE, oldest); |
| fd = open(path, O_CREAT | O_TRUNC | O_WRONLY | O_NOFOLLOW | O_CLOEXEC, 0600); |
| if (fd < 0) { |
| ALOGE("debuggerd: failed to open tombstone file '%s': %s\n", path, strerror(errno)); |
| return -1; |
| } |
| |
| if (out_path) { |
| *out_path = path; |
| } |
| fchown(fd, AID_SYSTEM, AID_SYSTEM); |
| return fd; |
| } |
| |
| void engrave_tombstone(int tombstone_fd, BacktraceMap* map, pid_t pid, pid_t tid, |
| const std::set<pid_t>& siblings, int signal, int original_si_code, |
| uintptr_t abort_msg_address, std::string* amfd_data) { |
| log_t log; |
| log.current_tid = tid; |
| log.crashed_tid = tid; |
| |
| if (tombstone_fd < 0) { |
| ALOGE("debuggerd: skipping tombstone write, nothing to do.\n"); |
| return; |
| } |
| |
| log.tfd = tombstone_fd; |
| log.amfd_data = amfd_data; |
| dump_crash(&log, map, pid, tid, siblings, signal, original_si_code, abort_msg_address); |
| } |