/* source: error.c */
/* Copyright Gerhard Rieger and contributors (see file CHANGES) */
/* Published under the GNU General Public License V.2, see file COPYING */
/* the logging subsystem */
#include "config.h"
#include "sysincludes.h"
#include "mytypes.h"
#include "compat.h"
#include "utils.h"
#include "vsnprintf_r.h"
#include "snprinterr.h"
#include "error.h"
#include "sycls.h"
/* translate MSG level to SYSLOG level */
int syslevel[] = {
LOG_DEBUG,
LOG_INFO,
LOG_NOTICE,
LOG_WARNING,
LOG_ERR,
LOG_CRIT };
struct diag_opts {
const char *progname;
int msglevel;
int exitlevel;
int syslog;
FILE *logfile;
int logfacility;
bool micros;
int exitstatus; /* pass signal number to error exit */
bool withhostname; /* in custom logs add hostname */
char *hostname;
} ;
static void _diag_exit(int status);
struct diag_opts diagopts =
{ NULL, E_ERROR, E_ERROR, 0, NULL, LOG_DAEMON, false, 0 } ;
static void msg2(
#if HAVE_CLOCK_GETTIME
struct timespec *now,
#elif HAVE_GETTIMEOFDAY
struct timeval *now,
#else
time_t *now,
#endif
int level, int exitcode, int handler, const char *text);
static void _msg(int level, const char *buff, const char *syslp);
sig_atomic_t diag_in_handler; /* !=0 indicates to msg() that in signal handler */
sig_atomic_t diag_immediate_msg; /* !=0 prints messages even from within signal handler instead of deferring them */
sig_atomic_t diag_immediate_exit; /* !=0 calls exit() from diag_exit() even when in signal handler. For system() */
static struct wordent facilitynames[] = {
{"auth", (void *)LOG_AUTH},
#ifdef LOG_AUTHPRIV
{"authpriv", (void *)LOG_AUTHPRIV},
#endif
#ifdef LOG_CONSOLE
{"console", (void *)LOG_CONSOLE},
#endif
{"cron", (void *)LOG_CRON},
{"daemon", (void *)LOG_DAEMON},
#ifdef LOG_FTP
{"ftp", (void *)LOG_FTP},
#endif
{"kern", (void *)LOG_KERN},
{"local0", (void *)LOG_LOCAL0},
{"local1", (void *)LOG_LOCAL1},
{"local2", (void *)LOG_LOCAL2},
{"local3", (void *)LOG_LOCAL3},
{"local4", (void *)LOG_LOCAL4},
{"local5", (void *)LOG_LOCAL5},
{"local6", (void *)LOG_LOCAL6},
{"local7", (void *)LOG_LOCAL7},
{"lpr", (void *)LOG_LPR},
{"mail", (void *)LOG_MAIL},
{"news", (void *)LOG_NEWS},
#ifdef LOG_SECURITY
{"security", (void *)LOG_SECURITY},
#endif
{"syslog", (void *)LOG_SYSLOG},
{"user", (void *)LOG_USER},
{"uucp", (void *)LOG_UUCP}
} ;
/* serialize message for sending from signal handlers */
struct sermsg {
int severity;
#if HAVE_CLOCK_GETTIME
struct timespec ts;
#else
struct timeval tv;
#endif
} ;
static int diaginitialized;
static int diag_sock_send = -1;
static int diag_sock_recv = -1;
static int diag_msg_avail = 0; /* !=0: messages from within signal handler may be waiting */
static int diag_init(void) {
int handlersocks[2];
if (diaginitialized) {
return 0;
}
diaginitialized = 1;
/* gcc with GNU libc refuses to set this in the initializer */
diagopts.logfile = stderr;
if (socketpair(AF_UNIX, SOCK_DGRAM, 0, handlersocks) < 0) {
diag_sock_send = -1;
diag_sock_recv = -1;
return -1;
}
diag_sock_send = handlersocks[1];
diag_sock_recv = handlersocks[0];
return 0;
}
#define DIAG_INIT ((void)(diaginitialized || diag_init()))
void diag_set(char what, const char *arg) {
DIAG_INIT;
switch (what) {
const struct wordent *keywd;
case 'y': diagopts.syslog = true;
if (arg && arg[0]) {
if ((keywd =
keyw(facilitynames, arg,
sizeof(facilitynames)/sizeof(struct wordent))) == NULL) {
Error1("unknown syslog facility \"%s\"", arg);
} else {
diagopts.logfacility = (int)(size_t)keywd->desc;
}
}
openlog(diagopts.progname, LOG_PID, diagopts.logfacility);
if (diagopts.logfile != NULL && diagopts.logfile != stderr) {
fclose(diagopts.logfile);
}
diagopts.logfile = NULL;
break;
case 'f':
if (diagopts.logfile != NULL && diagopts.logfile != stderr) {
fclose(diagopts.logfile);
}
if ((diagopts.logfile = fopen(arg, "a")) == NULL) {
Error2("cannot open log file \"%s\": %s", arg, strerror(errno));
}
break;
case 's':
if (diagopts.logfile != NULL && diagopts.logfile != stderr) {
fclose(diagopts.logfile);
}
diagopts.logfile = stderr; break; /* logging to stderr is default */
case 'p': diagopts.progname = arg;
openlog(diagopts.progname, LOG_PID, diagopts.logfacility);
break;
case 'd': --diagopts.msglevel; break;
case 'u': diagopts.micros = true; break;
default: msg(E_ERROR, "unknown diagnostic option %c", what);
}
}
void diag_set_int(char what, int arg) {
DIAG_INIT;
switch (what) {
case 'D': diagopts.msglevel = arg; break;
case 'e': diagopts.exitlevel = arg; break;
case 'x': diagopts.exitstatus = arg; break;
case 'h': diagopts.withhostname = arg;
if ((diagopts.hostname = getenv("HOSTNAME")) == NULL) {
struct utsname ubuf;
uname(&ubuf);
diagopts.hostname = strdup(ubuf.nodename);
}
break;
default: msg(E_ERROR, "unknown diagnostic option %c", what);
}
}
int diag_get_int(char what) {
DIAG_INIT;
switch (what) {
case 'y': return diagopts.syslog;
case 's': return diagopts.logfile == stderr;
case 'd': case 'D': return diagopts.msglevel;
case 'e': return diagopts.exitlevel;
}
return -1;
}
const char *diag_get_string(char what) {
DIAG_INIT;
switch (what) {
case 'p': return diagopts.progname;
}
return NULL;
}
/* Linux and AIX syslog format:
Oct 4 17:10:37 hostname socat[52798]: D signal(13, 1)
*/
void msg(int level, const char *format, ...) {
struct diag_dgram diag_dgram;
va_list ap;
/* does not perform a system call if nothing todo, thanks diag_msg_avail */
diag_dgram._errno = errno; /* keep for passing from signal handler to sock.
reason is that strerror is definitely not
async-signal-safe */
DIAG_INIT;
/* in normal program flow (not in signal handler) */
/* first flush the queue of datagrams from the socket */
if (diag_msg_avail && !diag_in_handler) {
diag_msg_avail = 0; /* _before_ flush to prevent inconsistent state when signal occurs inbetween */
diag_flush();
}
if (level < diagopts.msglevel) { return; }
va_start(ap, format);
/* we do only a minimum in the outer parts which may run in a signal handler
these are: get actual time, level, serialized message and write them to socket
*/
diag_dgram.op = DIAG_OP_MSG;
#if HAVE_CLOCK_GETTIME
clock_gettime(CLOCK_REALTIME, &diag_dgram.now);
#elif HAVE_GETTIMEOFDAY
gettimeofday(&diag_dgram.now, NULL);
#else
diag_dgram.now = time(NULL);
#endif
diag_dgram.level = level;
diag_dgram.exitcode = diagopts.exitstatus;
vsnprintf_r(diag_dgram.text, sizeof(diag_dgram.text), format, ap);
if (diag_in_handler && !diag_immediate_msg) {
send(diag_sock_send, &diag_dgram, sizeof(diag_dgram)-TEXTLEN + strlen(diag_dgram.text)+1, MSG_DONTWAIT
#ifdef MSG_NOSIGNAL
|MSG_NOSIGNAL
#endif
);
diag_msg_avail = 1;
va_end(ap);
return;
}
msg2(&diag_dgram.now, diag_dgram.level, diagopts.exitstatus, 0, diag_dgram.text);
va_end(ap); return;
}
void msg2(
#if HAVE_CLOCK_GETTIME
struct timespec *now,
#elif HAVE_GETTIMEOFDAY
struct timeval *now,
#else
time_t *now,
#endif
int level, /* E_INFO... */
int exitcode, /* on exit use this exit code */
int handler, /* message comes from signal handler */
const char *text) {
time_t epoch;
unsigned long micros;
#if HAVE_STRFTIME
struct tm struct_tm;
#endif
#define BUFLEN 512
char buff[BUFLEN], *bufp, *syslp;
size_t bytes;
#if HAVE_CLOCK_GETTIME
epoch = now->tv_sec;
#elif HAVE_GETTIMEOFDAY
epoch = now->tv_sec;
#else
epoch = *now;
#endif
#if HAVE_STRFTIME
bytes = strftime(buff, 20, "%Y/%m/%d %H:%M:%S", localtime_r(&epoch, &struct_tm));
buff[bytes] = '\0';
#else
bytes = snprintf(buff, 11, F_time, epoch);
#endif
if (diagopts.micros) {
#if HAVE_CLOCK_GETTIME
micros = now->tv_nsec/1000;
#elif HAVE_GETTIMEOFDAY
micros = now->tv_usec;
#else
micros = 0;
#endif
bytes += sprintf(buff+19, ".%06lu ", micros);
} else {
buff[19] = ' '; buff[20] = '\0';
}
bytes = strlen(buff);
bufp = buff + bytes;
if (diagopts.withhostname) {
bytes = sprintf(bufp, "%s ", diagopts.hostname), bufp+=bytes;
}
bytes = sprintf(bufp, "%s["F_pid"] ", diagopts.progname, getpid());
bufp += bytes;
syslp = bufp;
*bufp++ = "DINWEF"[level];
#if 0 /* only for debugging socat */
if (handler) bufp[-1] = tolower(bufp[-1]); /* for debugging, low chars indicate messages from signal handlers */
#endif
*bufp++ = ' ';
strncpy(bufp, text, BUFLEN-(bufp-buff)-1);
strcat(bufp, "\n");
_msg(level, buff, syslp);
if (level >= diagopts.exitlevel) {
if (E_NOTICE >= diagopts.msglevel) {
snprintf_r(syslp, 16, "N exit(%d)\n", exitcode?exitcode:(diagopts.exitstatus?diagopts.exitstatus:1));
_msg(E_NOTICE, buff, syslp);
}
exit(exitcode?exitcode:(diagopts.exitstatus?diagopts.exitstatus:1));
}
}
static void _msg(int level, const char *buff, const char *syslp) {
if (diagopts.syslog) {
/* prevent format string attacks (thanks to CoKi) */
syslog(syslevel[level], "%s", syslp);
}
if (diagopts.logfile) {
fputs(buff, diagopts.logfile); fflush(diagopts.logfile);
}
}
/* handle the messages in the queue */
void diag_flush(void) {
struct diag_dgram recv_dgram;
char exitmsg[20];
while (recv(diag_sock_recv, &recv_dgram, sizeof(recv_dgram)-1, MSG_DONTWAIT) > 0) {
recv_dgram.text[TEXTLEN-1] = '\0';
switch (recv_dgram.op) {
case DIAG_OP_EXIT:
/* we want the actual time, not when this dgram was sent */
#if HAVE_CLOCK_GETTIME
clock_gettime(CLOCK_REALTIME, &recv_dgram.now);
#elif HAVE_GETTIMEOFDAY
gettimeofday(&recv_dgram.now, NULL);
#else
recv_dgram.now = time(NULL);
#endif
if (E_NOTICE >= diagopts.msglevel) {
snprintf_r(exitmsg, sizeof(exitmsg), "exit(%d)", recv_dgram.exitcode?recv_dgram.exitcode:1);
msg2(&recv_dgram.now, E_NOTICE, recv_dgram.exitcode?recv_dgram.exitcode:1, 1, exitmsg);
}
exit(recv_dgram.exitcode?recv_dgram.exitcode:1);
case DIAG_OP_MSG:
if (recv_dgram._errno) {
/* there might be a %m control in the string (glibc compatible,
replace with strerror(...errno) ) */
char text[TEXTLEN];
errno = recv_dgram._errno;
snprinterr(text, TEXTLEN, recv_dgram.text);
msg2(&recv_dgram.now, recv_dgram.level, recv_dgram.exitcode, 1, text);
} else {
msg2(&recv_dgram.now, recv_dgram.level, recv_dgram.exitcode, 1, recv_dgram.text);
}
break;
}
}
}
/* use a new log output file descriptor that is dup'ed from the current one.
this is useful when socat logs to stderr but fd 2 should be redirected to
serve other purposes */
int diag_dup(void) {
int newfd;
DIAG_INIT;
if (diagopts.logfile == NULL) {
return -1;
}
newfd = dup(fileno(diagopts.logfile));
if (diagopts.logfile != stderr) {
fclose(diagopts.logfile);
}
if (newfd >= 0) {
diagopts.logfile = fdopen(newfd, "w");
}
return newfd;
}
/* this function is kind of async-signal-safe exit(). When invoked from signal
handler it defers exit. */
void diag_exit(int status) {
struct diag_dgram diag_dgram;
if (diag_in_handler && !diag_immediate_exit) {
diag_dgram.op = DIAG_OP_EXIT;
diag_dgram.exitcode = status;
send(diag_sock_send, &diag_dgram, sizeof(diag_dgram)-TEXTLEN, MSG_DONTWAIT
#ifdef MSG_NOSIGNAL
|MSG_NOSIGNAL
#endif
);
return;
}
_diag_exit(status);
}
static void _diag_exit(int status) {
Exit(status);
}
/* a function that appears to the application like select() but that also
monitors the diag socket diag_sock_recv and processes its messages.
Do not call from within a signal handler. */
int diag_select(int nfds, fd_set *readfds, fd_set *writefds,
fd_set *exceptfds, struct timeval *timeout) {
int result;
fd_set save_readfds, save_writefds, save_exceptfds;
if (readfds) { memcpy(&save_readfds, readfds, sizeof(*readfds)); }
if (writefds) { memcpy(&save_writefds, writefds, sizeof(*writefds)); }
if (exceptfds) { memcpy(&save_exceptfds, exceptfds, sizeof(*exceptfds)); }
while (1) {
FD_SET(diag_sock_recv, readfds);
result = Select(nfds, readfds, writefds,
exceptfds, timeout);
if (!FD_ISSET(diag_sock_recv, readfds)) {
/* select terminated not due to diag_sock_recv, normalt continuation */
break;
}
diag_flush();
if (readfds) { memcpy(readfds, &save_readfds, sizeof(*readfds)); }
if (writefds) { memcpy(writefds, &save_writefds, sizeof(*writefds)); }
if (exceptfds) { memcpy(exceptfds, &save_exceptfds, sizeof(*exceptfds)); }
}
return result;
}