diff options
Diffstat (limited to 'src/rc-logger.c')
| -rw-r--r-- | src/rc-logger.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/rc-logger.c b/src/rc-logger.c new file mode 100644 index 0000000..fa3303c --- /dev/null +++ b/src/rc-logger.c @@ -0,0 +1,235 @@ +/* + rc-logger.c + Spawns a logging daemon to capture stdout and stderr so we can log + them to a buffer and/or files. + + Copyright 2007 Gentoo Foundation + Released under the GPLv2 + */ + +#include <sys/types.h> +#include <sys/wait.h> +#include <ctype.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <termios.h> +#include <time.h> +#include <unistd.h> + +#ifdef __linux__ +# include <pty.h> +#else +# include <libutil.h> +#endif + +#include "einfo.h" +#include "rc-logger.h" +#include "rc-misc.h" +#include "rc.h" + +#define LOGFILE RC_SVCDIR "/rc.log" +#define PERMLOG "/var/log/rc.log" +#define MOVELOG "mv " LOGFILE " " PERMLOG ".$$.tmp && cat " PERMLOG \ + ".$$.tmp >>" PERMLOG " 2>/dev/null && rm -f " PERMLOG ".$$.tmp" + +static int signal_pipe[2] = { -1, -1 }; +static int fd_stdout = -1; +static int fd_stderr = -1; +static const char *runlevel = NULL; +static bool in_escape = false; +static bool in_term = false; + +static char *logbuf = NULL; +static size_t logbuf_size = 0; +static size_t logbuf_len = 0; + +pid_t rc_logger_pid = -1; +int rc_logger_tty = -1; +bool rc_in_logger = false; + +static void write_log (int logfd, const char *buffer, size_t bytes) +{ + const char *p = buffer; + + while ((size_t) (p - buffer) < bytes) { + switch (*p) { + case '\r': + goto cont; + case '\033': + in_escape = true; + in_term = false; + goto cont; + case '\n': + in_escape = in_term = false; + break; + case '[': + if (in_escape) + in_term = true; + break; + } + + if (! in_escape) { + write (logfd, p++, 1); + continue; + } + + if (! in_term || isalpha (*p)) + in_escape = in_term = false; +cont: + p++; + } +} + +static void write_time (FILE *f, const char *s) +{ + time_t now = time (NULL); + struct tm *tm = localtime (&now); + + fprintf (f, "\nrc %s logging %s at %s\n", runlevel, s, asctime (tm)); + fflush (f); +} + +void rc_logger_close () +{ + if (signal_pipe[1] > -1) { + int sig = SIGTERM; + write (signal_pipe[1], &sig, sizeof (sig)); + close (signal_pipe[1]); + signal_pipe[1] = -1; + } + + if (rc_logger_pid > 0) + waitpid (rc_logger_pid, 0, 0); + + if (fd_stdout > -1) + dup2 (fd_stdout, STDOUT_FILENO); + if (fd_stderr > -1) + dup2 (fd_stderr, STDERR_FILENO); +} + +void rc_logger_open (const char *level) +{ + int slave_tty; + struct termios tt; + struct winsize ws; + char *buffer; + fd_set rset; + int s; + size_t bytes; + int selfd; + int i; + FILE *log = NULL; + + if (! isatty (STDOUT_FILENO)) + return; + + if (! rc_env_bool ("RC_LOGGER")) + return; + + if (pipe (signal_pipe) == -1) + eerrorx ("pipe: %s", strerror (errno)); + for (i = 0; i < 2; i++) + if ((s = fcntl (signal_pipe[i], F_GETFD, 0) == -1 || + fcntl (signal_pipe[i], F_SETFD, s | FD_CLOEXEC) == -1)) + eerrorx ("fcntl: %s", strerror (errno)); + + tcgetattr (STDOUT_FILENO, &tt); + ioctl (STDOUT_FILENO, TIOCGWINSZ, &ws); + + /* /dev/pts may not be available yet */ + if (openpty (&rc_logger_tty, &slave_tty, NULL, &tt, &ws)) + return; + + rc_logger_pid = fork (); + switch (rc_logger_pid) { + case -1: + eerror ("forkpty: %s", strerror (errno)); + break; + case 0: + rc_in_logger = true; + close (signal_pipe[1]); + signal_pipe[1] = -1; + + runlevel = level; + if ((log = fopen (LOGFILE, "a"))) + write_time (log, "started"); + else { + free (logbuf); + logbuf_size = RC_LINEBUFFER * 10; + logbuf = xmalloc (sizeof (char) * logbuf_size); + logbuf_len = 0; + } + + buffer = xmalloc (sizeof (char) * RC_LINEBUFFER); + selfd = rc_logger_tty > signal_pipe[0] ? rc_logger_tty : signal_pipe[0]; + while (1) { + FD_ZERO (&rset); + FD_SET (rc_logger_tty, &rset); + FD_SET (signal_pipe[0], &rset); + + if ((s = select (selfd + 1, &rset, NULL, NULL, NULL)) == -1) { + eerror ("select: %s", strerror (errno)); + break; + } + + if (s > 0) { + if (FD_ISSET (rc_logger_tty, &rset)) { + memset (buffer, 0, RC_LINEBUFFER); + bytes = read (rc_logger_tty, buffer, RC_LINEBUFFER); + write (STDOUT_FILENO, buffer, bytes); + + if (log) + write_log (fileno (log), buffer, bytes); + else { + if (logbuf_size - logbuf_len < bytes) { + logbuf_size += RC_LINEBUFFER * 10; + logbuf = xrealloc (logbuf, sizeof (char ) * + logbuf_size); + } + + memcpy (logbuf + logbuf_len, buffer, bytes); + logbuf_len += bytes; + } + } + + /* Only SIGTERMS signals come down this pipe */ + if (FD_ISSET (signal_pipe[0], &rset)) + break; + } + } + free (buffer); + if (logbuf) { + if ((log = fopen (LOGFILE, "a"))) { + write_time (log, "started"); + write_log (fileno (log), logbuf, logbuf_len); + } + free (logbuf); + } + if (log) { + write_time (log, "stopped"); + fclose (log); + } + + /* Try and cat our new logfile to a more permament location and then + * punt it */ + system (MOVELOG); + + exit (0); + default: + setpgid (rc_logger_pid, 0); + fd_stdout = dup (STDOUT_FILENO); + fd_stderr = dup (STDERR_FILENO); + dup2 (slave_tty, STDOUT_FILENO); + dup2 (slave_tty, STDERR_FILENO); + if (slave_tty != STDIN_FILENO && + slave_tty != STDOUT_FILENO && + slave_tty != STDERR_FILENO) + close (slave_tty); + close (signal_pipe[0]); + signal_pipe[0] = -1; + break; + } +} |