2 * This file is part of DisOrder.
3 * Copyright (C) 2004-2008 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 /** @file lib/log.c @brief Errors and logging
20 * All messages are initially emitted by one of the four functions
21 * below. disorder_debug() is generally invoked via D() so that
22 * mostly you just do a test rather than a complete subroutine call.
24 * Messages are dispatched via @ref log_default. This defaults to @ref
25 * log_stderr. daemonize() will turn off @ref log_stderr and use @ref
28 * disorder_fatal() will call exitfn() with a nonzero status. The
29 * default value is exit(), but it should be set to _exit() anywhere
30 * but the 'main line' of the program, to guarantee that exit() gets
31 * called at most once.
34 #define NO_MEMORY_ALLOCATION
35 /* because the memory allocation functions report errors */
48 /** @brief Definition of a log output */
50 /** @brief Function to call */
51 void (*fn
)(int pri
, const char *msg
, void *user
);
52 /** @brief User data */
56 /** @brief Function to call on a fatal error
58 * This is normally @c exit() but in the presence of @c fork() it
59 * sometimes gets set to @c _exit(). */
60 void (*exitfn
)(int) attribute((noreturn
)) = exit
;
62 /** @brief Debug flag */
65 /** @brief Program name */
68 /** @brief Filename for debug messages */
69 const char *debug_filename
;
71 /** @brief Set to include timestamps in log messages */
74 /** @brief Line number for debug messages */
77 /** @brief Pointer to chosen log output structure */
78 struct log_output
*log_default
= &log_stderr
;
80 /** @brief Filename to debug for */
81 static const char *debug_only
;
83 /** @brief Construct log line, encoding special characters
85 * We might be receiving things in any old encoding, or binary rubbish
86 * in no encoding at all, so escape anything we don't like the look
87 * of. We limit the log message to a kilobyte.
89 static void format(char buffer
[], size_t bufsize
, const char *fmt
, va_list ap
) {
95 if(byte_vsnprintf(t
, sizeof t
, fmt
, ap
) < 0) {
96 strcpy(t
, "[byte_vsnprintf failed: ");
97 strncat(t
, fmt
, sizeof t
- strlen(t
) - 1);
100 while((ch
= (unsigned char)*p
++)) {
101 if(ch
>= ' ' && ch
<= 126) {
102 if(n
< bufsize
) buffer
[n
++] = ch
;
104 if(n
< bufsize
) buffer
[n
++] = '\\';
105 if(n
< bufsize
) buffer
[n
++] = '0' + ((ch
>> 6) & 7);
106 if(n
< bufsize
) buffer
[n
++] = '0' + ((ch
>> 3) & 7);
107 if(n
< bufsize
) buffer
[n
++] = '0' + ((ch
>> 0) & 7);
115 /** @brief Log to a file
116 * @param pri Message priority (as per syslog)
117 * @param msg Messagge to log
118 * @param user The @c FILE @c * to log to or NULL for @c stderr
120 static void logfp(int pri
, const char *msg
, void *user
) {
122 FILE *fp
= user ? user
: stderr
;
123 /* ...because stderr is not a constant so we can't initialize log_stderr
130 gettimeofday(&tv
, 0);
131 tm
= localtime(&tv
.tv_sec
);
132 strftime(timebuf
, sizeof timebuf
, "%Y-%m-%d %H:%M:%S %Z", tm
);
133 fprintf(fp
, "%s: ", timebuf
);
136 fprintf(fp
, "%s: ", progname
);
138 fputs("ERROR: ", fp
);
139 else if(pri
< LOG_DEBUG
)
143 if(!(debug_only
= getenv("DISORDER_DEBUG_ONLY")))
146 gettimeofday(&tv
, 0);
148 while(!strncmp(p
, "../", 3)) p
+= 3;
149 if(*debug_only
&& strcmp(p
, debug_only
))
151 fprintf(fp
, "%llu.%06lu: %s:%d: ",
152 (unsigned long long)tv
.tv_sec
, (unsigned long)tv
.tv_usec
,
159 /** @brief Log to syslog */
160 static void logsyslog(int pri
, const char *msg
,
161 void attribute((unused
)) *user
) {
163 syslog(pri
, "%s", msg
);
165 syslog(pri
, "%s:%d: %s", debug_filename
, debug_lineno
, msg
);
168 /** @brief Log output that writes to @c stderr */
169 struct log_output log_stderr
= { logfp
, 0 };
171 /** @brief Log output that sends to syslog */
172 struct log_output log_syslog
= { logsyslog
, 0 };
174 /** @brief Format and log a message */
175 static void vlogger(int pri
, const char *fmt
, va_list ap
) {
178 format(buffer
, sizeof buffer
, fmt
, ap
);
179 log_default
->fn(pri
, buffer
, log_default
->user
);
182 /** @brief Format and log a message */
183 static void logger(int pri
, const char *fmt
, ...) {
187 vlogger(pri
, fmt
, ap
);
191 /** @brief Format and log a message
192 * @param pri Message priority (as per syslog)
193 * @param fmt Format string
194 * @param errno_value Errno value to include as a string, or 0
195 * @param ap Argument list
197 void elog(int pri
, int errno_value
, const char *fmt
, va_list ap
) {
201 vlogger(pri
, fmt
, ap
);
203 memset(buffer
, 0, sizeof buffer
);
204 byte_vsnprintf(buffer
, sizeof buffer
, fmt
, ap
);
205 buffer
[sizeof buffer
- 1] = 0;
206 logger(pri
, "%s: %s", buffer
, strerror(errno_value
));
210 /** @brief Log an error and quit
212 * If @c ${DISORDER_FATAL_ABORT} is defined (as anything) then the process
213 * is aborted, so you can get a backtrace.
215 void disorder_fatal(int errno_value
, const char *msg
, ...) {
219 elog(LOG_CRIT
, errno_value
, msg
, ap
);
221 if(getenv("DISORDER_FATAL_ABORT")) abort();
222 exitfn(EXIT_FAILURE
);
225 /** @brief Log an error */
226 void disorder_error(int errno_value
, const char *msg
, ...) {
230 elog(LOG_ERR
, errno_value
, msg
, ap
);
234 /** @brief Log an informational message */
235 void disorder_info(const char *msg
, ...) {
239 elog(LOG_INFO
, 0, msg
, ap
);
243 /** @brief Log a debug message */
244 void disorder_debug(const char *msg
, ...) {
248 vlogger(LOG_DEBUG
, msg
, ap
);
252 /** @brief Set the program name from @c argc */
253 void set_progname(char **argv
) {
254 if((progname
= strrchr(argv
[0], '/')))