4 * DEBUG: section 0 Debug Routines
5 * AUTHOR: Harvest Derived
7 * SQUID Web Proxy Cache http://www.squid-cache.org/
8 * ----------------------------------------------------------
10 * Squid is the result of efforts by numerous individuals from
11 * the Internet community; see the CONTRIBUTORS file for full
12 * details. Many organizations have provided support for Squid's
13 * development; see the SPONSORS file for full details. Squid is
14 * Copyrighted (C) 2001 by the Regents of the University of
15 * California; see the COPYRIGHT file for full details. Squid
16 * incorporates software developed and/or copyrighted by other
17 * sources; see the CREDITS file for full details.
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
37 #include "SquidTime.h"
40 /* for shutting_down flag in xassert() */
43 /* cope with no squid.h */
45 #define MAXPATHLEN 256
48 char *Debug::debugOptions
= NULL
;
49 int Debug::override_X
= 0;
50 int Debug::log_stderr
= -1;
51 bool Debug::log_syslog
= false;
52 int Debug::Levels
[MAX_DEBUG_SECTIONS
];
54 char *Debug::cache_log
= NULL
;
55 int Debug::rotateNumber
= -1;
56 FILE *debug_log
= NULL
;
57 static char *debug_log_file
= NULL
;
58 static int Ctx_Lock
= 0;
59 static const char *debugLogTime(void);
60 static void ctx_print(void);
63 static int syslog_facility
= 0;
65 static void _db_print_syslog(const char *format
, va_list args
);
67 static void _db_print_stderr(const char *format
, va_list args
);
68 static void _db_print_file(const char *format
, va_list args
);
71 SQUIDCEXTERN LPCRITICAL_SECTION dbg_mutex
;
72 typedef BOOL (WINAPI
* PFInitializeCriticalSectionAndSpinCount
) (LPCRITICAL_SECTION
, DWORD
);
76 _db_print(const char *format
,...)
78 char f
[BUFSIZ
]; f
[0]='\0';
84 /* Multiple WIN32 threads may call this simultaneously */
87 HMODULE krnl_lib
= GetModuleHandle("Kernel32");
88 PFInitializeCriticalSectionAndSpinCount InitializeCriticalSectionAndSpinCount
= NULL
;
91 InitializeCriticalSectionAndSpinCount
=
92 (PFInitializeCriticalSectionAndSpinCount
) GetProcAddress(krnl_lib
,
93 "InitializeCriticalSectionAndSpinCount");
95 dbg_mutex
= static_cast<CRITICAL_SECTION
*>(xcalloc(1, sizeof(CRITICAL_SECTION
)));
97 if (InitializeCriticalSectionAndSpinCount
) {
98 /* let multiprocessor systems EnterCriticalSection() fast */
100 if (!InitializeCriticalSectionAndSpinCount(dbg_mutex
, 4000)) {
102 fprintf(debug_log
, "FATAL: _db_print: can't initialize critical section\n");
106 fprintf(stderr
, "FATAL: _db_print: can't initialize critical section\n");
109 InitializeCriticalSection(dbg_mutex
);
113 EnterCriticalSection(dbg_mutex
);
116 /* give a chance to context-based debugging to print current context */
120 va_start(args1
, format
);
121 va_start(args2
, format
);
122 va_start(args3
, format
);
124 snprintf(f
, BUFSIZ
, "%s| %s",
128 _db_print_file(f
, args1
);
129 _db_print_stderr(f
, args2
);
132 _db_print_syslog(format
, args3
);
136 LeaveCriticalSection(dbg_mutex
);
145 _db_print_file(const char *format
, va_list args
)
147 if (debug_log
== NULL
)
150 /* give a chance to context-based debugging to print current context */
154 vfprintf(debug_log
, format
, args
);
159 _db_print_stderr(const char *format
, va_list args
)
161 if (Debug::log_stderr
< Debug::level
)
164 if (debug_log
== stderr
)
167 vfprintf(stderr
, format
, args
);
172 _db_print_syslog(const char *format
, va_list args
)
174 /* level 0,1 go to syslog */
176 if (Debug::level
> 1)
179 if (!Debug::log_syslog
)
185 vsnprintf(tmpbuf
, BUFSIZ
, format
, args
);
187 tmpbuf
[BUFSIZ
- 1] = '\0';
189 syslog(Debug::level
== 0 ? LOG_WARNING
: LOG_NOTICE
, "%s", tmpbuf
);
191 #endif /* HAVE_SYSLOG */
194 debugArg(const char *arg
)
200 if (!strncasecmp(arg
, "rotate=", 7)) {
202 Debug::rotateNumber
= atoi(arg
);
204 } else if (!strncasecmp(arg
, "ALL", 3)) {
209 while (*arg
&& *arg
++ != ',');
215 if (s
>= MAX_DEBUG_SECTIONS
)
216 s
= MAX_DEBUG_SECTIONS
-1;
225 Debug::Levels
[s
] = l
;
229 for (i
= 0; i
< MAX_DEBUG_SECTIONS
; i
++)
230 Debug::Levels
[i
] = l
;
234 debugOpenLog(const char *logfile
)
236 if (logfile
== NULL
) {
242 xfree(debug_log_file
);
244 debug_log_file
= xstrdup(logfile
); /* keep a static copy */
246 if (debug_log
&& debug_log
!= stderr
)
249 debug_log
= fopen(logfile
, "a+");
252 fprintf(stderr
, "WARNING: Cannot write log file: %s\n", logfile
);
254 fprintf(stderr
, " messages will be sent to 'stderr'.\n");
260 setmode(fileno(debug_log
), O_TEXT
);
268 static struct syslog_facility_name
{
273 syslog_facility_names
[] = {
282 "authpriv", LOG_AUTHPRIV
383 _db_set_syslog(const char *facility
)
385 Debug::log_syslog
= true;
390 syslog_facility
= LOG_DAEMON
;
393 syslog_facility
= LOG_LOCAL4
;
394 #endif /* LOG_DAEMON */
398 struct syslog_facility_name
*n
;
400 for (n
= syslog_facility_names
; n
->name
; n
++) {
401 if (strcmp(n
->name
, facility
) == 0) {
402 syslog_facility
= n
->facility
;
407 fprintf(stderr
, "unknown syslog facility '%s'\n", facility
);
413 fprintf(stderr
, "syslog facility type not supported on your system\n");
415 #endif /* LOG_LOCAL4 */
421 Debug::parseOptions(char const *options
)
428 debugs(0, 9, "command-line -X overrides: " << options
);
432 for (i
= 0; i
< MAX_DEBUG_SECTIONS
; i
++)
433 Debug::Levels
[i
] = 0;
436 p
= xstrdup(options
);
438 for (s
= strtok(p
, w_space
); s
; s
= strtok(NULL
, w_space
))
446 _db_init(const char *logfile
, const char *options
)
448 Debug::parseOptions(options
);
450 debugOpenLog(logfile
);
452 #if HAVE_SYSLOG && defined(LOG_LOCAL4)
454 if (Debug::log_syslog
)
455 openlog(APP_SHORTNAME
, LOG_PID
| LOG_NDELAY
| LOG_CONS
, syslog_facility
);
457 #endif /* HAVE_SYSLOG */
459 /* Pre-Init TZ env, see bug #2656 */
466 if (debug_log_file
== NULL
)
471 if (stat(debug_log_file
, &sb
) == 0)
472 if (S_ISREG(sb
.st_mode
) == 0)
476 char from
[MAXPATHLEN
];
483 * NOTE: we cannot use xrename here without having it in a
484 * separate file -- tools.c has too many dependencies to be
485 * used everywhere debug.c is used.
487 /* Rotate numbers 0 through N up one */
488 for (int i
= Debug::rotateNumber
; i
> 1;) {
490 snprintf(from
, MAXPATHLEN
, "%s.%d", debug_log_file
, i
- 1);
491 snprintf(to
, MAXPATHLEN
, "%s.%d", debug_log_file
, i
);
500 * You can't rename open files on Microsoft "operating systems"
501 * so we close before renaming.
504 if (debug_log
!= stderr
)
507 /* Rotate the current log to .0 */
508 if (Debug::rotateNumber
> 0) {
509 snprintf(to
, MAXPATHLEN
, "%s.%d", debug_log_file
, 0);
514 rename(debug_log_file
, to
);
517 /* Close and reopen the log. It may have been renamed "manually"
518 * before HUP'ing us. */
519 if (debug_log
!= stderr
)
520 debugOpenLog(Debug::cache_log
);
527 time_t t
= getCurrentTime();
530 static char buf
[128];
531 static time_t last_t
= 0;
533 if (Debug::level
> 1) {
536 strftime(buf2
, 127, "%Y/%m/%d %H:%M:%S", tm
);
538 snprintf(buf
, 127, "%s.%03d", buf2
, (int) current_time
.tv_usec
/ 1000);
540 } else if (t
!= last_t
) {
542 strftime(buf
, 127, "%Y/%m/%d %H:%M:%S", tm
);
551 xassert(const char *msg
, const char *file
, int line
)
553 debugs(0, 0, "assertion failed: " << file
<< ":" << line
<< ": \"" << msg
<< "\"");
560 * Context-based Debugging
565 * When you have a long nested processing sequence, it is often impossible
566 * for low level routines to know in what larger context they operate. If a
567 * routine coredumps, one can restore the context using debugger trace.
568 * However, in many case you do not want to coredump, but just want to report
569 * a potential problem. A report maybe useless out of problem context.
571 * To solve this potential problem, use the following approach:
574 * top_level_foo(const char *url)
576 * // define current context
577 * // note: we stack but do not dup ctx descriptions!
578 * Ctx ctx = ctx_enter(url);
580 * // go down; middle_level_bar will eventually call bottom_level_boo
581 * middle_level_bar(method, protocol);
583 * // exit, clean after yourself
588 * bottom_level_boo(int status, void *data)
590 * // detect exceptional condition, and simply report it, the context
591 * // information will be available somewhere close in the log file
592 * if (status == STRANGE_STATUS)
593 * debugs(13, 6, "DOS attack detected, data: " << data);
597 * Current implementation is extremely simple but still very handy. It has a
598 * negligible overhead (descriptions are not duplicated).
600 * When the _first_ debug message for a given context is printed, it is
601 * prepended with the current context description. Context is printed with
602 * the same debugging level as the original message.
604 * Note that we do not print context every type you do ctx_enter(). This
605 * approach would produce too many useless messages. For the same reason, a
606 * context description is printed at most _once_ even if you have 10
607 * debugging messages within one context.
609 * Contexts can be nested, of course. You must use ctx_enter() to enter a
610 * context (push it onto stack). It is probably safe to exit several nested
611 * contexts at _once_ by calling ctx_exit() at the top level (this will pop
612 * all context till current one). However, as in any stack, you cannot start
616 * i) locate debugging message,
617 * ii) locate current context by going _upstream_ in your log file,
624 * decide if we want to dup() descriptions (adds overhead) but allows to
625 * add printf()-style interface
630 * descriptions for contexts over CTX_MAX_LEVEL limit are ignored, you probably
631 * have a bug if your nesting goes that deep.
634 #define CTX_MAX_LEVEL 255
637 * produce a warning when nesting reaches this level and then double
640 static int Ctx_Warn_Level
= 32;
641 /* all descriptions has been printed up to this level */
642 static int Ctx_Reported_Level
= -1;
643 /* descriptions are still valid or active up to this level */
644 static int Ctx_Valid_Level
= -1;
645 /* current level, the number of nested ctx_enter() calls */
646 static int Ctx_Current_Level
= -1;
647 /* saved descriptions (stack) */
648 static const char *Ctx_Descrs
[CTX_MAX_LEVEL
+ 1];
649 /* "safe" get secription */
650 static const char *ctx_get_descr(Ctx ctx
);
654 ctx_enter(const char *descr
)
658 if (Ctx_Current_Level
<= CTX_MAX_LEVEL
)
659 Ctx_Descrs
[Ctx_Current_Level
] = descr
;
661 if (Ctx_Current_Level
== Ctx_Warn_Level
) {
662 debugs(0, 0, "# ctx: suspiciously deep (" << Ctx_Warn_Level
<< ") nesting:");
666 return Ctx_Current_Level
;
673 Ctx_Current_Level
= (ctx
>= 0) ? ctx
- 1 : -1;
675 if (Ctx_Valid_Level
> Ctx_Current_Level
)
676 Ctx_Valid_Level
= Ctx_Current_Level
;
680 * the idea id to print each context description at most once but provide enough
681 * info for deducing the current execution stack
686 /* lock so _db_print will not call us recursively */
688 /* ok, user saw [0,Ctx_Reported_Level] descriptions */
689 /* first inform about entries popped since user saw them */
691 if (Ctx_Valid_Level
< Ctx_Reported_Level
) {
692 if (Ctx_Reported_Level
!= Ctx_Valid_Level
+ 1)
693 _db_print("ctx: exit levels from %2d down to %2d\n",
694 Ctx_Reported_Level
, Ctx_Valid_Level
+ 1);
696 _db_print("ctx: exit level %2d\n", Ctx_Reported_Level
);
698 Ctx_Reported_Level
= Ctx_Valid_Level
;
701 /* report new contexts that were pushed since last report */
702 while (Ctx_Reported_Level
< Ctx_Current_Level
) {
703 Ctx_Reported_Level
++;
705 _db_print("ctx: enter level %2d: '%s'\n", Ctx_Reported_Level
,
706 ctx_get_descr(Ctx_Reported_Level
));
713 /* checks for nulls and overflows */
715 ctx_get_descr(Ctx ctx
)
717 if (ctx
< 0 || ctx
> CTX_MAX_LEVEL
)
720 return Ctx_Descrs
[ctx
] ? Ctx_Descrs
[ctx
] : "<null>";
723 int Debug::TheDepth
= 0;
728 assert(TheDepth
>= 0);
731 assert(CurrentDebug
);
732 *CurrentDebug
<< std::endl
<< "reentrant debuging " << TheDepth
<< "-{";
734 assert(!CurrentDebug
);
735 CurrentDebug
= new std::ostringstream();
736 // set default formatting flags
737 CurrentDebug
->setf(std::ios::fixed
);
738 CurrentDebug
->precision(2);
740 return *CurrentDebug
;
746 assert(TheDepth
>= 0);
747 assert(CurrentDebug
);
749 *CurrentDebug
<< "}-" << TheDepth
<< std::endl
;
751 assert(TheDepth
== 1);
752 _db_print("%s\n", CurrentDebug
->str().c_str());
759 // Hack: replaces global ::xassert() to debug debugging assertions
760 // Relies on assert macro calling xassert() without a specific scope.
762 Debug::xassert(const char *msg
, const char *file
, int line
)
766 *CurrentDebug
<< "assertion failed: " << file
<< ":" << line
<<
767 ": \"" << msg
<< "\"";
772 std::ostringstream (*Debug::CurrentDebug
)(NULL
);
777 // XXX: This must be kept in sync with the actual debug.cc location
778 const char *ThisFileNameTail
= "src/debug.cc";
780 const char *file
=__FILE__
;
782 // Disable heuristic if it does not work.
783 if (!strstr(file
, ThisFileNameTail
))
786 return strlen(file
)-strlen(ThisFileNameTail
);
790 SkipBuildPrefix(const char* path
)
792 static const size_t BuildPrefixLength
= BuildPrefixInit();
794 return path
+BuildPrefixLength
;