/*
* UCW Library -- Logging
*
- * (c) 1997--2008 Martin Mares <mj@ucw.cz>
+ * (c) 1997--2009 Martin Mares <mj@ucw.cz>
+ * (c) 2008 Tomas Gavenciak <gavento@ucw.cz>
*
* This software may be freely distributed and used according to the terms
* of the GNU Lesser General Public License.
*/
#include "ucw/lib.h"
+#include "ucw/log.h"
+#include "ucw/simple-lists.h"
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <time.h>
#include <alloca.h>
+#include <errno.h>
-static char log_progname[32];
-char *log_filename;
char *log_title;
int log_pid;
-int log_precise_timings;
void (*log_die_hook)(void);
-void (*log_switch_hook)(struct tm *tm);
+
+/*** The default log stream, which logs to stderr ***/
+
+static int default_log_handler(struct log_stream *ls, struct log_msg *m)
+{
+ // This is a completely bare version of the log-file module. Errors are ignored.
+ write(ls->idata, m->m, m->m_len);
+ return 0;
+}
+
+const struct log_stream log_stream_default = {
+ .name = "stderr",
+ .idata = 2,
+ .handler = default_log_handler,
+ .levels = LS_ALL_LEVELS,
+ .msgfmt = LSFMT_DEFAULT,
+ // an empty clist
+ .substreams.head.next = (cnode *) &log_stream_default.substreams.head,
+ .substreams.head.prev = (cnode *) &log_stream_default.substreams.head,
+};
+
+/*** Registry of streams and their identifiers ***/
+
+struct lsbuf_t log_streams; /* A growing array of pointers to log_streams */
+int log_streams_after = 0; /* The first never-used index in log_streams.ptr */
+
+/*
+ * Find a stream by its identifier given as LS_SET_STRNUM(flags).
+ * Returns NULL if the stream doesn't exist or it's invalid.
+ *
+ * If the log-stream machinery has not been initialized (which is normal for programs
+ * with no fancy logging), the log_streams gbuf is empty and this function only
+ * translates stream #0 to the static log_stream_default.
+ */
+
+struct log_stream *
+log_stream_by_flags(uns flags)
+{
+ int n = LS_GET_STRNUM(flags);
+ if (n < 0 || n >= log_streams_after || log_streams.ptr[n]->regnum == -1)
+ return (n ? NULL : (struct log_stream *) &log_stream_default);
+ return log_streams.ptr[n];
+}
+
+/*** Logging ***/
void
-vmsg(unsigned int cat, const char *fmt, va_list args)
+vmsg(uns cat, const char *fmt, va_list args)
{
struct timeval tv;
- int have_tm = 0;
struct tm tm;
- byte *buf, *p;
- int buflen = 256;
- int l, l0, r;
va_list args2;
+ char stime[24];
+ char sutime[12];
+ char msgbuf[256];
+ char *p;
+ int len;
+ struct log_stream *ls = log_stream_by_flags(cat);
+ struct log_msg m = { .flags = cat };
+
+ /* Check the stream existence */
+ if (!ls)
+ {
+ msg((LS_INTERNAL_MASK&cat)|L_WARN, "No log_stream with number %d! Logging to the default log.", LS_GET_STRNUM(cat));
+ ls = (struct log_stream *) &log_stream_default;
+ }
- if (!(cat & L_SIGHANDLER))
+ /* Get the current time */
+ if (!(cat & LSFLAG_SIGHANDLER))
{
/* CAVEAT: These calls are not safe in signal handlers. */
gettimeofday(&tv, NULL);
if (localtime_r(&tv.tv_sec, &tm))
- have_tm = 1;
- if (log_switch_hook)
- log_switch_hook(&tm);
+ m.tm = &tm;
}
- while (1)
+ /* Generate time strings */
+ if (m.tm)
{
- p = buf = alloca(buflen);
- *p++ = cat & 0xff;
- if (have_tm)
- {
- p += strftime(p, buflen, " %Y-%m-%d %H:%M:%S", &tm);
- if (log_precise_timings)
- p += sprintf(p, ".%06d", (int)tv.tv_usec);
- }
- else
- {
- p += sprintf(p, " \?\?\?\?-\?\?-\?\? \?\?:\?\?:\?\?");
- if (log_precise_timings)
- p += sprintf(p, ".\?\?\?\?\?\?");
- }
+ strftime(stime, sizeof(stime), "%Y-%m-%d %H:%M:%S", &tm);
+ snprintf(sutime, sizeof(sutime), ".%06d", (int)tv.tv_usec);
+ m.stime = stime;
+ m.sutime = sutime;
+ }
+ else
+ {
+ m.stime = "\?\?\?\?-\?\?-\?\? \?\?:\?\?:\?\?";
+ m.sutime = ".\?\?\?\?\?\?";
+ }
+
+ /* Generate the message string */
+ va_copy(args2, args);
+ len = vsnprintf(msgbuf, sizeof(msgbuf), fmt, args2);
+ va_end(args2);
+ if (len < (int) sizeof(msgbuf))
+ m.raw_msg = msgbuf;
+ else
+ {
+ m.raw_msg = xmalloc(len+1);
+ vsnprintf(m.raw_msg, len+1, fmt, args);
+ }
+
+ /* Remove non-printable characters and newlines */
+ p = m.raw_msg;
+ while (*p)
+ {
+ if (*p < 0x20 && *p != '\t')
+ *p = 0x7f;
+ p++;
+ }
+
+ /* Pass the message to the log_stream */
+ if (log_pass_msg(0, ls, &m))
+ {
+ /* Error (such as infinite loop) occurred */
+ log_pass_msg(0, (struct log_stream *) &log_stream_default, &m);
+ }
+
+ if (m.raw_msg != msgbuf)
+ xfree(m.raw_msg);
+}
+
+/* Maximal depth of log_pass_msg recursion */
+#define LS_MAX_DEPTH 64
+
+int
+log_pass_msg(int depth, struct log_stream *ls, struct log_msg *m)
+{
+ ASSERT(ls);
+
+ /* Check recursion depth */
+ if (depth > LS_MAX_DEPTH)
+ {
+ struct log_msg errm = *m;
+ errm.flags = L_ERROR | (m->flags & LS_INTERNAL_MASK);
+ errm.raw_msg = "Loop in the log_stream system detected.";
+ log_pass_msg(0, (struct log_stream *) &log_stream_default, &errm);
+ }
+
+ /* Filter by level and hook function */
+ if (!((1 << LS_GET_LEVEL(m->flags)) & ls->levels))
+ return 0;
+ if (ls->filter && ls->filter(ls, m))
+ return 0;
+
+ /* Pass the message to substreams */
+ CLIST_FOR_EACH(simp_node *, s, ls->substreams)
+ if (log_pass_msg(depth+1, s->p, m))
+ return 1;
+
+ /* Will pass to the handler of this stream... is there any? */
+ if (!ls->handler)
+ return 0;
+
+ /* Upper bound on message length */
+ int len = strlen(m->raw_msg) + strlen(m->stime) + strlen(m->sutime) + 32;
+ if (log_title)
+ len += strlen(log_title);
+ if (ls->name)
+ len += strlen(ls->name);
+
+ /* Get a buffer and format the message */
+ char *free_buf = NULL;
+ if (len <= 256)
+ m->m = alloca(len);
+ else
+ m->m = free_buf = xmalloc(len);
+ char *p = m->m;
+
+ /* Level (2 chars) */
+ if (ls->msgfmt & LSFMT_LEVEL)
+ {
+ *p++ = LS_LEVEL_LETTER(LS_GET_LEVEL(m->flags));
*p++ = ' ';
- if (log_title)
+ }
+
+ /* Time (|stime| + |sutime| + 1 chars) */
+ if (ls->msgfmt & LSFMT_TIME)
+ {
+ const char *q = m->stime;
+ while (*q)
+ *p++ = *q++;
+ if (ls->msgfmt & LSFMT_USEC)
{
- if (log_pid)
- p += sprintf(p, "[%s (%d)] ", log_title, log_pid);
- else
- p += sprintf(p, "[%s] ", log_title);
+ q = m->sutime;
+ while (*q)
+ *p++ = *q++;
}
+ *p++ = ' ';
+ }
+
+ /* Process name, PID ( |log_title| + 6 + (|PID|<=10) chars ) */
+ if ((ls->msgfmt & LSFMT_TITLE) && log_title)
+ {
+ if (ls->msgfmt & LSFMT_PID)
+ p += sprintf(p, "[%s (%d)] ", log_title, log_pid);
else
- {
- if (log_pid)
- p += sprintf(p, "[%d] ", log_pid);
- }
- l0 = p - buf + 1;
- r = buflen - l0;
- va_copy(args2, args);
- l = vsnprintf(p, r, fmt, args2);
- va_end(args2);
- if (l < 0)
- l = r;
- else if (l < r)
- {
- while (*p)
- {
- if (*p < 0x20 && *p != '\t')
- *p = 0x7f;
- p++;
- }
- *p = '\n';
- write(2, buf, l + l0);
- return;
- }
- buflen = l + l0 + 1;
+ p += sprintf(p, "[%s] ", log_title);
+ }
+ else
+ {
+ if (ls->msgfmt & LSFMT_PID)
+ p += sprintf(p, "[%d] ", log_pid);
}
+
+ /* log_stream name ( |ls->name| + 4 chars ) */
+ if (ls->msgfmt & LSFMT_LOGNAME)
+ {
+ if (ls->name)
+ p += sprintf(p, "<%s> ", ls->name);
+ else
+ p += sprintf(p, "<?> ");
+ }
+
+ /* The message itself ( |m| + 1 chars ) */
+ {
+ const char *q = m->raw_msg;
+ while (*q)
+ *p++ = *q++;
+ *p++ = '\n';
+ *p = '\0';
+ m->m_len = p - m->m;
+ ls->handler(ls, m);
+ }
+
+ if (free_buf)
+ xfree(free_buf);
+ return 0;
}
+/*** Utility functions ***/
+
void
msg(unsigned int cat, const char *fmt, ...)
{
{
if (argv0)
{
+ static char log_progname[32];
strncpy(log_progname, log_basename(argv0), sizeof(log_progname)-1);
log_progname[sizeof(log_progname)-1] = 0;
log_title = log_progname;
}
}
+
+void
+log_fork(void)
+{
+ log_pid = getpid();
+}
+
+#ifdef TEST
+
+#include <syslog.h>
+
+int main(void)
+{
+ struct log_stream *ls = log_new_syslog(LOG_USER, "syslog");
+ msg(L_INFO | ls->regnum, "Brum <%300s>", ":-)");
+ return 0;
+}
+
+#endif