diff options
| -rw-r--r-- | logwrapper/logwrap.c | 151 |
1 files changed, 49 insertions, 102 deletions
diff --git a/logwrapper/logwrap.c b/logwrapper/logwrap.c index 129ffb1..bf91977 100644 --- a/logwrapper/logwrap.c +++ b/logwrapper/logwrap.c @@ -17,7 +17,6 @@ #include <string.h> #include <sys/types.h> #include <sys/socket.h> -#include <signal.h> #include <poll.h> #include <sys/wait.h> #include <stdio.h> @@ -35,7 +34,6 @@ #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) -static int signal_fd_write; static pthread_mutex_t fd_mutex = PTHREAD_MUTEX_INITIALIZER; #define ERROR(fmt, args...) \ @@ -50,94 +48,77 @@ do { \ _exit(-1); \ } while(0) -static int parent(const char *tag, int parent_read, int signal_fd, pid_t pid, - int *chld_sts, bool logwrap) { +static int parent(const char *tag, int parent_read, pid_t pid, int *chld_sts, + bool logwrap) { int status = 0; char buffer[4096]; struct pollfd poll_fds[] = { [0] = { - .fd = signal_fd, - .events = POLLIN, - }, - [1] = { .fd = parent_read, .events = POLLIN, }, }; int rc = 0; - sigset_t chldset; int a = 0; // start index of unprocessed data int b = 0; // end index of unprocessed data int sz; - bool remote_hung = false; bool found_child = false; char *btag = basename(tag); if (!btag) btag = (char*) tag; - sigemptyset(&chldset); - sigaddset(&chldset, SIGCHLD); - pthread_sigmask(SIG_UNBLOCK, &chldset, NULL); - while (!found_child) { - if (TEMP_FAILURE_RETRY(poll(poll_fds, remote_hung ? 1 : 2, -1)) < 0) { + if (TEMP_FAILURE_RETRY(poll(poll_fds, ARRAY_SIZE(poll_fds), -1)) < 0) { ERROR("poll failed\n"); rc = -1; goto err_poll; } - if (!remote_hung) { - if (poll_fds[1].revents & POLLIN) { - sz = read(parent_read, &buffer[b], sizeof(buffer) - 1 - b); - - sz += b; - // Log one line at a time - for (b = 0; b < sz; b++) { - if (buffer[b] == '\r') { - buffer[b] = '\0'; - } else if (buffer[b] == '\n') { - buffer[b] = '\0'; - if (logwrap) - ALOG(LOG_INFO, btag, "%s", &buffer[a]); - a = b + 1; - } - } + if (poll_fds[0].revents & POLLIN) { + sz = read(parent_read, &buffer[b], sizeof(buffer) - 1 - b); - if (a == 0 && b == sizeof(buffer) - 1) { - // buffer is full, flush + sz += b; + // Log one line at a time + for (b = 0; b < sz; b++) { + if (buffer[b] == '\r') { + buffer[b] = '\0'; + } else if (buffer[b] == '\n') { buffer[b] = '\0'; if (logwrap) ALOG(LOG_INFO, btag, "%s", &buffer[a]); - b = 0; - } else if (a != b) { - // Keep left-overs - b -= a; - memmove(buffer, &buffer[a], b); - a = 0; - } else { - a = 0; - b = 0; + a = b + 1; } } - if (poll_fds[1].revents & POLLHUP) { - remote_hung = true; + if (a == 0 && b == sizeof(buffer) - 1) { + // buffer is full, flush + buffer[b] = '\0'; + if (logwrap) + ALOG(LOG_INFO, btag, "%s", &buffer[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 & POLLIN) { - char tmp[32]; + if (poll_fds[0].revents & POLLHUP) { int ret; - read(signal_fd, tmp, sizeof(tmp)); - while (!found_child) { - ret = TEMP_FAILURE_RETRY(waitpid(-1, &status, WNOHANG)); - - if (ret <= 0) - break; - - found_child = (pid == ret); + ret = waitpid(pid, &status, WNOHANG); + 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; } } } @@ -171,6 +152,7 @@ static int parent(const char *tag, int parent_read, int signal_fd, pid_t pid, } } +err_waitpid: err_poll: return rc; } @@ -187,23 +169,16 @@ static void child(int argc, char* argv[], bool logwrap) { } } -static void sigchld_handler(int sig) { - write(signal_fd_write, &sig, 1); -} - int android_fork_execvp(int argc, char* argv[], int *status, bool ignore_int_quit, bool logwrap) { pid_t pid; int parent_ptty; int child_ptty; char *child_devname = NULL; - struct sigaction chldact; - struct sigaction oldchldact; struct sigaction intact; struct sigaction quitact; sigset_t blockset; sigset_t oldset; - int sockets[2]; int rc = 0; rc = pthread_mutex_lock(&fd_mutex); @@ -227,14 +202,21 @@ int android_fork_execvp(int argc, char* argv[], int *status, bool ignore_int_qui goto err_ptty; } + child_ptty = 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); - sigaddset(&blockset, SIGCHLD); pthread_sigmask(SIG_BLOCK, &blockset, &oldset); pid = fork(); if (pid < 0) { + close(child_ptty); ERROR("Failed to fork\n"); rc = -1; goto err_fork; @@ -243,12 +225,6 @@ int android_fork_execvp(int argc, char* argv[], int *status, bool ignore_int_qui pthread_sigmask(SIG_SETMASK, &oldset, NULL); close(parent_ptty); - child_ptty = open(child_devname, O_RDWR); - if (child_ptty < 0) { - FATAL_CHILD("Problem with child ptty\n"); - return -1; - } - // redirect stdout and stderr dup2(child_ptty, 1); dup2(child_ptty, 2); @@ -256,55 +232,26 @@ int android_fork_execvp(int argc, char* argv[], int *status, bool ignore_int_qui child(argc, argv, logwrap); } else { - struct sigaction ignact; - - memset(&chldact, 0, sizeof(chldact)); - chldact.sa_handler = sigchld_handler; - chldact.sa_flags = SA_NOCLDSTOP; - - sigaction(SIGCHLD, &chldact, &oldchldact); - if ((!(oldchldact.sa_flags & SA_SIGINFO) && - oldchldact.sa_handler != SIG_DFL && - oldchldact.sa_handler != SIG_IGN) || - ((oldchldact.sa_flags & SA_SIGINFO) && - oldchldact.sa_sigaction != NULL)) { - ALOG(LOG_WARN, "logwrapper", "logwrap replaced the SIGCHLD " - "handler and might cause interaction issues"); - } - + 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); } - rc = socketpair(AF_UNIX, SOCK_STREAM, 0, sockets); - if (rc == -1) { - ERROR("socketpair failed: %s\n", strerror(errno)); - goto err_socketpair; - } - - fcntl(sockets[0], F_SETFD, FD_CLOEXEC); - fcntl(sockets[0], F_SETFL, O_NONBLOCK); - fcntl(sockets[1], F_SETFD, FD_CLOEXEC); - fcntl(sockets[1], F_SETFL, O_NONBLOCK); - - signal_fd_write = sockets[0]; - - rc = parent(argv[0], parent_ptty, sockets[1], pid, status, logwrap); + rc = parent(argv[0], parent_ptty, pid, status, logwrap); } - close(sockets[0]); - close(sockets[1]); -err_socketpair: if (ignore_int_quit) { sigaction(SIGINT, &intact, NULL); sigaction(SIGQUIT, &quitact, NULL); } - sigaction(SIGCHLD, &oldchldact, NULL); err_fork: pthread_sigmask(SIG_SETMASK, &oldset, NULL); +err_child_ptty: err_ptty: close(parent_ptty); err_open: |