| /* |
| * Copyright 2008, 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. |
| */ |
| |
| #include "utility.h" |
| |
| #include <errno.h> |
| #include <signal.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <sys/ptrace.h> |
| #include <sys/wait.h> |
| |
| #include <backtrace/Backtrace.h> |
| #include <log/log.h> |
| #include <log/logd.h> |
| |
| const int sleep_time_usec = 50000; // 0.05 seconds |
| const int max_total_sleep_usec = 10000000; // 10 seconds |
| |
| static int write_to_am(int fd, const char* buf, int len) { |
| int to_write = len; |
| while (to_write > 0) { |
| int written = TEMP_FAILURE_RETRY(write(fd, buf + len - to_write, to_write)); |
| if (written < 0) { |
| // hard failure |
| LOG("AM write failure (%d / %s)\n", errno, strerror(errno)); |
| return -1; |
| } |
| to_write -= written; |
| } |
| return len; |
| } |
| |
| void _LOG(log_t* log, int scopeFlags, const char* fmt, ...) { |
| bool want_tfd_write = log && log->tfd >= 0; |
| bool want_log_write = IS_AT_FAULT(scopeFlags) && (!log || !log->quiet); |
| bool want_amfd_write = IS_AT_FAULT(scopeFlags) && !IS_SENSITIVE(scopeFlags) && log && log->amfd >= 0; |
| |
| char buf[512]; |
| va_list ap; |
| va_start(ap, fmt); |
| vsnprintf(buf, sizeof(buf), fmt, ap); |
| va_end(ap); |
| |
| size_t len = strlen(buf); |
| if (len <= 0) { |
| return; |
| } |
| |
| if (want_tfd_write) { |
| TEMP_FAILURE_RETRY(write(log->tfd, buf, len)); |
| } |
| |
| if (want_log_write) { |
| __android_log_buf_write(LOG_ID_CRASH, ANDROID_LOG_INFO, "DEBUG", buf); |
| if (want_amfd_write) { |
| int written = write_to_am(log->amfd, buf, len); |
| if (written <= 0) { |
| // timeout or other failure on write; stop informing the activity manager |
| log->amfd = -1; |
| } |
| } |
| } |
| } |
| |
| int wait_for_signal(pid_t tid, int* total_sleep_time_usec) { |
| for (;;) { |
| int status; |
| pid_t n = waitpid(tid, &status, __WALL | WNOHANG); |
| if (n < 0) { |
| if (errno == EAGAIN) |
| continue; |
| LOG("waitpid failed: %s\n", strerror(errno)); |
| return -1; |
| } else if (n > 0) { |
| XLOG("waitpid: n=%d status=%08x\n", n, status); |
| if (WIFSTOPPED(status)) { |
| return WSTOPSIG(status); |
| } else { |
| LOG("unexpected waitpid response: n=%d, status=%08x\n", n, status); |
| return -1; |
| } |
| } |
| |
| if (*total_sleep_time_usec > max_total_sleep_usec) { |
| LOG("timed out waiting for tid=%d to die\n", tid); |
| return -1; |
| } |
| |
| // not ready yet |
| XLOG("not ready yet\n"); |
| usleep(sleep_time_usec); |
| *total_sleep_time_usec += sleep_time_usec; |
| } |
| } |
| |
| void wait_for_stop(pid_t tid, int* total_sleep_time_usec) { |
| siginfo_t si; |
| while (TEMP_FAILURE_RETRY(ptrace(PTRACE_GETSIGINFO, tid, 0, &si)) < 0 && errno == ESRCH) { |
| if (*total_sleep_time_usec > max_total_sleep_usec) { |
| LOG("timed out waiting for tid=%d to stop\n", tid); |
| break; |
| } |
| |
| usleep(sleep_time_usec); |
| *total_sleep_time_usec += sleep_time_usec; |
| } |
| } |
| |
| #if defined (__mips__) |
| #define DUMP_MEMORY_AS_ASCII 1 |
| #else |
| #define DUMP_MEMORY_AS_ASCII 0 |
| #endif |
| |
| void dump_memory(log_t* log, pid_t tid, uintptr_t addr, int scope_flags) { |
| char code_buffer[64]; |
| char ascii_buffer[32]; |
| uintptr_t p, end; |
| |
| p = addr & ~(sizeof(long) - 1); |
| /* Dump 32 bytes before addr */ |
| p -= 32; |
| if (p > addr) { |
| /* catch underflow */ |
| p = 0; |
| } |
| /* Dump 256 bytes */ |
| end = p + 256; |
| /* catch overflow; 'end - p' has to be multiples of 16 */ |
| while (end < p) { |
| end -= 16; |
| } |
| |
| /* Dump the code around PC as: |
| * addr contents ascii |
| * 0000000000008d34 ef000000e8bd0090 e1b00000512fff1e ............../Q |
| * 0000000000008d44 ea00b1f9e92d0090 e3a070fcef000000 ......-..p...... |
| * On 32-bit machines, there are still 16 bytes per line but addresses and |
| * words are of course presented differently. |
| */ |
| while (p < end) { |
| char* asc_out = ascii_buffer; |
| |
| int len = snprintf(code_buffer, sizeof(code_buffer), "%" PRIPTR " ", p); |
| |
| for (size_t i = 0; i < 16/sizeof(long); i++) { |
| long data = ptrace(PTRACE_PEEKTEXT, tid, (void*)p, NULL); |
| if (data == -1 && errno != 0) { |
| // ptrace failed, probably because we're dumping memory in an |
| // unmapped or inaccessible page. |
| #ifdef __LP64__ |
| len += sprintf(code_buffer + len, "---------------- "); |
| #else |
| len += sprintf(code_buffer + len, "-------- "); |
| #endif |
| } else { |
| len += sprintf(code_buffer + len, "%" PRIPTR " ", |
| static_cast<uintptr_t>(data)); |
| } |
| |
| #if DUMP_MEMORY_AS_ASCII |
| for (size_t j = 0; j < sizeof(long); j++) { |
| /* |
| * Our isprint() allows high-ASCII characters that display |
| * differently (often badly) in different viewers, so we |
| * just use a simpler test. |
| */ |
| char val = (data >> (j*8)) & 0xff; |
| if (val >= 0x20 && val < 0x7f) { |
| *asc_out++ = val; |
| } else { |
| *asc_out++ = '.'; |
| } |
| } |
| #endif |
| p += sizeof(long); |
| } |
| *asc_out = '\0'; |
| _LOG(log, scope_flags, " %s %s\n", code_buffer, ascii_buffer); |
| } |
| } |