| /* |
| * Copyright (C) 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 <errno.h> |
| #include <fcntl.h> |
| #include <libgen.h> |
| #include <poll.h> |
| #include <pthread.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/socket.h> |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| #include <android/log.h> |
| #include <cutils/klog.h> |
| #include <logwrap/logwrap.h> |
| #include <private/android_filesystem_config.h> |
| |
| #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) |
| #define MIN(a,b) (((a)<(b))?(a):(b)) |
| |
| static pthread_mutex_t fd_mutex = PTHREAD_MUTEX_INITIALIZER; |
| |
| #define ERROR(fmt, args...) \ |
| do { \ |
| fprintf(stderr, fmt, ## args); \ |
| ALOG(LOG_ERROR, "logwrapper", fmt, ## args); \ |
| } while(0) |
| |
| #define FATAL_CHILD(fmt, args...) \ |
| do { \ |
| ERROR(fmt, ## args); \ |
| _exit(-1); \ |
| } while(0) |
| |
| #define MAX_KLOG_TAG 16 |
| |
| /* This is a simple buffer that holds up to the first beginning_buf->buf_size |
| * bytes of output from a command. |
| */ |
| #define BEGINNING_BUF_SIZE 0x1000 |
| struct beginning_buf { |
| char *buf; |
| size_t alloc_len; |
| /* buf_size is the usable space, which is one less than the allocated size */ |
| size_t buf_size; |
| size_t used_len; |
| }; |
| |
| /* This is a circular buf that holds up to the last ending_buf->buf_size bytes |
| * of output from a command after the first beginning_buf->buf_size bytes |
| * (which are held in beginning_buf above). |
| */ |
| #define ENDING_BUF_SIZE 0x1000 |
| struct ending_buf { |
| char *buf; |
| ssize_t alloc_len; |
| /* buf_size is the usable space, which is one less than the allocated size */ |
| ssize_t buf_size; |
| ssize_t used_len; |
| /* read and write offsets into the circular buffer */ |
| int read; |
| int write; |
| }; |
| |
| /* A structure to hold all the abbreviated buf data */ |
| struct abbr_buf { |
| struct beginning_buf b_buf; |
| struct ending_buf e_buf; |
| int beginning_buf_full; |
| }; |
| |
| /* Collect all the various bits of info needed for logging in one place. */ |
| struct log_info { |
| int log_target; |
| char klog_fmt[MAX_KLOG_TAG * 2]; |
| char *btag; |
| bool abbreviated; |
| FILE *fp; |
| struct abbr_buf a_buf; |
| }; |
| |
| /* Forware declaration */ |
| static void add_line_to_abbr_buf(struct abbr_buf *a_buf, char *linebuf, int linelen); |
| |
| /* Return 0 on success, and 1 when full */ |
| static int add_line_to_linear_buf(struct beginning_buf *b_buf, |
| char *line, ssize_t line_len) |
| { |
| int full = 0; |
| |
| if ((line_len + b_buf->used_len) > b_buf->buf_size) { |
| full = 1; |
| } else { |
| /* Add to the end of the buf */ |
| memcpy(b_buf->buf + b_buf->used_len, line, line_len); |
| b_buf->used_len += line_len; |
| } |
| |
| return full; |
| } |
| |
| static void add_line_to_circular_buf(struct ending_buf *e_buf, |
| char *line, ssize_t line_len) |
| { |
| ssize_t free_len; |
| ssize_t needed_space; |
| int cnt; |
| |
| if (e_buf->buf == NULL) { |
| return; |
| } |
| |
| if (line_len > e_buf->buf_size) { |
| return; |
| } |
| |
| free_len = e_buf->buf_size - e_buf->used_len; |
| |
| if (line_len > free_len) { |
| /* remove oldest entries at read, and move read to make |
| * room for the new string */ |
| needed_space = line_len - free_len; |
| e_buf->read = (e_buf->read + needed_space) % e_buf->buf_size; |
| e_buf->used_len -= needed_space; |
| } |
| |
| /* Copy the line into the circular buffer, dealing with possible |
| * wraparound. |
| */ |
| cnt = MIN(line_len, e_buf->buf_size - e_buf->write); |
| memcpy(e_buf->buf + e_buf->write, line, cnt); |
| if (cnt < line_len) { |
| memcpy(e_buf->buf, line + cnt, line_len - cnt); |
| } |
| e_buf->used_len += line_len; |
| e_buf->write = (e_buf->write + line_len) % e_buf->buf_size; |
| } |
| |
| /* Log directly to the specified log */ |
| static void do_log_line(struct log_info *log_info, char *line) { |
| if (log_info->log_target & LOG_KLOG) { |
| klog_write(6, log_info->klog_fmt, line); |
| } |
| if (log_info->log_target & LOG_ALOG) { |
| ALOG(LOG_INFO, log_info->btag, "%s", line); |
| } |
| if (log_info->log_target & LOG_FILE) { |
| fprintf(log_info->fp, "%s\n", line); |
| } |
| } |
| |
| /* Log to either the abbreviated buf, or directly to the specified log |
| * via do_log_line() above. |
| */ |
| static void log_line(struct log_info *log_info, char *line, int len) { |
| if (log_info->abbreviated) { |
| add_line_to_abbr_buf(&log_info->a_buf, line, len); |
| } else { |
| do_log_line(log_info, line); |
| } |
| } |
| |
| /* |
| * The kernel will take a maximum of 1024 bytes in any single write to |
| * the kernel logging device file, so find and print each line one at |
| * a time. The allocated size for buf should be at least 1 byte larger |
| * than buf_size (the usable size of the buffer) to make sure there is |
| * room to temporarily stuff a null byte to terminate a line for logging. |
| */ |
| static void print_buf_lines(struct log_info *log_info, char *buf, int buf_size) |
| { |
| char *line_start; |
| char c; |
| int i; |
| |
| line_start = buf; |
| for (i = 0; i < buf_size; i++) { |
| if (*(buf + i) == '\n') { |
| /* Found a line ending, print the line and compute new line_start */ |
| /* Save the next char and replace with \0 */ |
| c = *(buf + i + 1); |
| *(buf + i + 1) = '\0'; |
| do_log_line(log_info, line_start); |
| /* Restore the saved char */ |
| *(buf + i + 1) = c; |
| line_start = buf + i + 1; |
| } else if (*(buf + i) == '\0') { |
| /* The end of the buffer, print the last bit */ |
| do_log_line(log_info, line_start); |
| break; |
| } |
| } |
| /* If the buffer was completely full, and didn't end with a newline, just |
| * ignore the partial last line. |
| */ |
| } |
| |
| static void init_abbr_buf(struct abbr_buf *a_buf) { |
| char *new_buf; |
| |
| memset(a_buf, 0, sizeof(struct abbr_buf)); |
| new_buf = malloc(BEGINNING_BUF_SIZE); |
| if (new_buf) { |
| a_buf->b_buf.buf = new_buf; |
| a_buf->b_buf.alloc_len = BEGINNING_BUF_SIZE; |
| a_buf->b_buf.buf_size = BEGINNING_BUF_SIZE - 1; |
| } |
| new_buf = malloc(ENDING_BUF_SIZE); |
| if (new_buf) { |
| a_buf->e_buf.buf = new_buf; |
| a_buf->e_buf.alloc_len = ENDING_BUF_SIZE; |
| a_buf->e_buf.buf_size = ENDING_BUF_SIZE - 1; |
| } |
| } |
| |
| static void free_abbr_buf(struct abbr_buf *a_buf) { |
| free(a_buf->b_buf.buf); |
| free(a_buf->e_buf.buf); |
| } |
| |
| static void add_line_to_abbr_buf(struct abbr_buf *a_buf, char *linebuf, int linelen) { |
| if (!a_buf->beginning_buf_full) { |
| a_buf->beginning_buf_full = |
| add_line_to_linear_buf(&a_buf->b_buf, linebuf, linelen); |
| } |
| if (a_buf->beginning_buf_full) { |
| add_line_to_circular_buf(&a_buf->e_buf, linebuf, linelen); |
| } |
| } |
| |
| static void print_abbr_buf(struct log_info *log_info) { |
| struct abbr_buf *a_buf = &log_info->a_buf; |
| |
| /* Add the abbreviated output to the kernel log */ |
| if (a_buf->b_buf.alloc_len) { |
| print_buf_lines(log_info, a_buf->b_buf.buf, a_buf->b_buf.used_len); |
| } |
| |
| /* Print an ellipsis to indicate that the buffer has wrapped or |
| * is full, and some data was not logged. |
| */ |
| if (a_buf->e_buf.used_len == a_buf->e_buf.buf_size) { |
| do_log_line(log_info, "...\n"); |
| } |
| |
| if (a_buf->e_buf.used_len == 0) { |
| return; |
| } |
| |
| /* Simplest way to print the circular buffer is allocate a second buf |
| * of the same size, and memcpy it so it's a simple linear buffer, |
| * and then cal print_buf_lines on it */ |
| if (a_buf->e_buf.read < a_buf->e_buf.write) { |
| /* no wrap around, just print it */ |
| print_buf_lines(log_info, a_buf->e_buf.buf + a_buf->e_buf.read, |
| a_buf->e_buf.used_len); |
| } else { |
| /* The circular buffer will always have at least 1 byte unused, |
| * so by allocating alloc_len here we will have at least |
| * 1 byte of space available as required by print_buf_lines(). |
| */ |
| char * nbuf = malloc(a_buf->e_buf.alloc_len); |
| if (!nbuf) { |
| return; |
| } |
| int first_chunk_len = a_buf->e_buf.buf_size - a_buf->e_buf.read; |
| memcpy(nbuf, a_buf->e_buf.buf + a_buf->e_buf.read, first_chunk_len); |
| /* copy second chunk */ |
| memcpy(nbuf + first_chunk_len, a_buf->e_buf.buf, a_buf->e_buf.write); |
| print_buf_lines(log_info, nbuf, first_chunk_len + a_buf->e_buf.write); |
| free(nbuf); |
| } |
| } |
| |
| static int parent(const char *tag, int parent_read, pid_t pid, |
| int *chld_sts, int log_target, bool abbreviated, char *file_path, |
| const struct AndroidForkExecvpOption* opts, size_t opts_len) { |
| int status = 0; |
| char buffer[4096]; |
| struct pollfd poll_fds[] = { |
| [0] = { |
| .fd = parent_read, |
| .events = POLLIN, |
| }, |
| }; |
| int rc = 0; |
| int fd; |
| |
| struct log_info log_info; |
| |
| int a = 0; // start index of unprocessed data |
| int b = 0; // end index of unprocessed data |
| int sz; |
| bool found_child = false; |
| char tmpbuf[256]; |
| |
| log_info.btag = basename(tag); |
| if (!log_info.btag) { |
| log_info.btag = (char*) tag; |
| } |
| |
| if (abbreviated && (log_target == LOG_NONE)) { |
| abbreviated = 0; |
| } |
| if (abbreviated) { |
| init_abbr_buf(&log_info.a_buf); |
| } |
| |
| if (log_target & LOG_KLOG) { |
| snprintf(log_info.klog_fmt, sizeof(log_info.klog_fmt), |
| "<6>%.*s: %%s\n", MAX_KLOG_TAG, log_info.btag); |
| } |
| |
| if ((log_target & LOG_FILE) && !file_path) { |
| /* No file_path specified, clear the LOG_FILE bit */ |
| log_target &= ~LOG_FILE; |
| } |
| |
| if (log_target & LOG_FILE) { |
| fd = open(file_path, O_WRONLY | O_CREAT, 0664); |
| if (fd < 0) { |
| ERROR("Cannot log to file %s\n", file_path); |
| log_target &= ~LOG_FILE; |
| } else { |
| lseek(fd, 0, SEEK_END); |
| log_info.fp = fdopen(fd, "a"); |
| } |
| } |
| |
| log_info.log_target = log_target; |
| log_info.abbreviated = abbreviated; |
| |
| while (!found_child) { |
| if (TEMP_FAILURE_RETRY(poll(poll_fds, ARRAY_SIZE(poll_fds), -1)) < 0) { |
| ERROR("poll failed\n"); |
| rc = -1; |
| goto err_poll; |
| } |
| |
| if (poll_fds[0].revents & POLLIN) { |
| sz = TEMP_FAILURE_RETRY( |
| read(parent_read, &buffer[b], sizeof(buffer) - 1 - b)); |
| |
| for (size_t i = 0; sz > 0 && i < opts_len; ++i) { |
| if (opts[i].opt_type == FORK_EXECVP_OPTION_CAPTURE_OUTPUT) { |
| opts[i].opt_capture_output.on_output( |
| (uint8_t*)&buffer[b], sz, opts[i].opt_capture_output.user_pointer); |
| } |
| } |
| |
| sz += b; |
| // Log one line at a time |
| for (b = 0; b < sz; b++) { |
| if (buffer[b] == '\r') { |
| if (abbreviated) { |
| /* The abbreviated logging code uses newline as |
| * the line separator. Lucikly, the pty layer |
| * helpfully cooks the output of the command |
| * being run and inserts a CR before NL. So |
| * I just change it to NL here when doing |
| * abbreviated logging. |
| */ |
| buffer[b] = '\n'; |
| } else { |
| buffer[b] = '\0'; |
| } |
| } else if (buffer[b] == '\n') { |
| buffer[b] = '\0'; |
| log_line(&log_info, &buffer[a], b - a); |
| a = b + 1; |
| } |
| } |
| |
| if (a == 0 && b == sizeof(buffer) - 1) { |
| // buffer is full, flush |
| buffer[b] = '\0'; |
| log_line(&log_info, &buffer[a], b - a); |
| b = 0; |
| } else if (a != b) { |
| // Keep left-overs |
| b -= a; |
| memmove(buffer, &buffer[a], b); |
| a = 0; |
| } else { |
| a = 0; |
| b = 0; |
| } |
| } |
| |
| if (poll_fds[0].revents & POLLHUP) { |
| int ret; |
| |
| ret = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0)); |
| if (ret < 0) { |
| rc = errno; |
| ALOG(LOG_ERROR, "logwrap", "waitpid failed with %s\n", strerror(errno)); |
| goto err_waitpid; |
| } |
| if (ret > 0) { |
| found_child = true; |
| } |
| } |
| } |
| |
| if (chld_sts != NULL) { |
| *chld_sts = status; |
| } else { |
| if (WIFEXITED(status)) |
| rc = WEXITSTATUS(status); |
| else |
| rc = -ECHILD; |
| } |
| |
| // Flush remaining data |
| if (a != b) { |
| buffer[b] = '\0'; |
| log_line(&log_info, &buffer[a], b - a); |
| } |
| |
| /* All the output has been processed, time to dump the abbreviated output */ |
| if (abbreviated) { |
| print_abbr_buf(&log_info); |
| } |
| |
| if (WIFEXITED(status)) { |
| if (WEXITSTATUS(status)) { |
| snprintf(tmpbuf, sizeof(tmpbuf), |
| "%s terminated by exit(%d)\n", log_info.btag, WEXITSTATUS(status)); |
| do_log_line(&log_info, tmpbuf); |
| } |
| } else { |
| if (WIFSIGNALED(status)) { |
| snprintf(tmpbuf, sizeof(tmpbuf), |
| "%s terminated by signal %d\n", log_info.btag, WTERMSIG(status)); |
| do_log_line(&log_info, tmpbuf); |
| } else if (WIFSTOPPED(status)) { |
| snprintf(tmpbuf, sizeof(tmpbuf), |
| "%s stopped by signal %d\n", log_info.btag, WSTOPSIG(status)); |
| do_log_line(&log_info, tmpbuf); |
| } |
| } |
| |
| err_waitpid: |
| err_poll: |
| if (log_target & LOG_FILE) { |
| fclose(log_info.fp); /* Also closes underlying fd */ |
| } |
| if (abbreviated) { |
| free_abbr_buf(&log_info.a_buf); |
| } |
| return rc; |
| } |
| |
| static void child(int argc, char* argv[]) { |
| // create null terminated argv_child array |
| char* argv_child[argc + 1]; |
| memcpy(argv_child, argv, argc * sizeof(char *)); |
| argv_child[argc] = NULL; |
| |
| if (execvp(argv_child[0], argv_child)) { |
| FATAL_CHILD("executing %s failed: %s\n", argv_child[0], |
| strerror(errno)); |
| } |
| } |
| |
| int android_fork_execvp_ext(int argc, char* argv[], int *status, bool ignore_int_quit, |
| int log_target, bool abbreviated, char *file_path, |
| const struct AndroidForkExecvpOption* opts, size_t opts_len) { |
| pid_t pid; |
| int parent_ptty; |
| int child_ptty; |
| struct sigaction intact; |
| struct sigaction quitact; |
| sigset_t blockset; |
| sigset_t oldset; |
| int rc = 0; |
| |
| rc = pthread_mutex_lock(&fd_mutex); |
| if (rc) { |
| ERROR("failed to lock signal_fd mutex\n"); |
| goto err_lock; |
| } |
| |
| /* Use ptty instead of socketpair so that STDOUT is not buffered */ |
| parent_ptty = TEMP_FAILURE_RETRY(open("/dev/ptmx", O_RDWR)); |
| if (parent_ptty < 0) { |
| ERROR("Cannot create parent ptty\n"); |
| rc = -1; |
| goto err_open; |
| } |
| |
| char child_devname[64]; |
| if (grantpt(parent_ptty) || unlockpt(parent_ptty) || |
| ptsname_r(parent_ptty, child_devname, sizeof(child_devname)) != 0) { |
| ERROR("Problem with /dev/ptmx\n"); |
| rc = -1; |
| goto err_ptty; |
| } |
| |
| child_ptty = TEMP_FAILURE_RETRY(open(child_devname, O_RDWR)); |
| if (child_ptty < 0) { |
| ERROR("Cannot open child_ptty\n"); |
| rc = -1; |
| goto err_child_ptty; |
| } |
| |
| sigemptyset(&blockset); |
| sigaddset(&blockset, SIGINT); |
| sigaddset(&blockset, SIGQUIT); |
| pthread_sigmask(SIG_BLOCK, &blockset, &oldset); |
| |
| pid = fork(); |
| if (pid < 0) { |
| close(child_ptty); |
| ERROR("Failed to fork\n"); |
| rc = -1; |
| goto err_fork; |
| } else if (pid == 0) { |
| pthread_mutex_unlock(&fd_mutex); |
| pthread_sigmask(SIG_SETMASK, &oldset, NULL); |
| close(parent_ptty); |
| |
| // redirect stdin, stdout and stderr |
| for (size_t i = 0; i < opts_len; ++i) { |
| if (opts[i].opt_type == FORK_EXECVP_OPTION_INPUT) { |
| dup2(child_ptty, 0); |
| break; |
| } |
| } |
| dup2(child_ptty, 1); |
| dup2(child_ptty, 2); |
| close(child_ptty); |
| |
| child(argc, argv); |
| } else { |
| close(child_ptty); |
| if (ignore_int_quit) { |
| struct sigaction ignact; |
| |
| memset(&ignact, 0, sizeof(ignact)); |
| ignact.sa_handler = SIG_IGN; |
| sigaction(SIGINT, &ignact, &intact); |
| sigaction(SIGQUIT, &ignact, &quitact); |
| } |
| |
| for (size_t i = 0; i < opts_len; ++i) { |
| if (opts[i].opt_type == FORK_EXECVP_OPTION_INPUT) { |
| size_t left = opts[i].opt_input.input_len; |
| const uint8_t* input = opts[i].opt_input.input; |
| while (left > 0) { |
| ssize_t res = |
| TEMP_FAILURE_RETRY(write(parent_ptty, input, left)); |
| if (res < 0) { |
| break; |
| } |
| left -= res; |
| input += res; |
| } |
| } |
| } |
| |
| rc = parent(argv[0], parent_ptty, pid, status, log_target, |
| abbreviated, file_path, opts, opts_len); |
| } |
| |
| if (ignore_int_quit) { |
| sigaction(SIGINT, &intact, NULL); |
| sigaction(SIGQUIT, &quitact, NULL); |
| } |
| err_fork: |
| pthread_sigmask(SIG_SETMASK, &oldset, NULL); |
| err_child_ptty: |
| err_ptty: |
| close(parent_ptty); |
| err_open: |
| pthread_mutex_unlock(&fd_mutex); |
| err_lock: |
| return rc; |
| } |