source3/lib/debug.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Samba utility functions
   5    Copyright (C) Andrew Tridgell 1992-1998
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 /* -------------------------------------------------------------------------- **
  25  * This module implements Samba's debugging utility.
  26  *
  27  * The syntax of a debugging log file is represented as:
  28  *
  29  *  <debugfile> :== { <debugmsg> }
  30  *
  31  *  <debugmsg>  :== <debughdr> '\n' <debugtext>
  32  *
  33  *  <debughdr>  :== '[' TIME ',' LEVEL ']' [ [FILENAME ':'] [FUNCTION '()'] ]
  34  *
  35  *  <debugtext> :== { <debugline> }
  36  *
  37  *  <debugline> :== TEXT '\n'
  38  *
  39  * TEXT     is a string of characters excluding the newline character.
  40  * LEVEL    is the DEBUG level of the message (an integer in the range 0..10).
  41  * TIME     is a timestamp.
  42  * FILENAME is the name of the file from which the debug message was generated.
  43  * FUNCTION is the function from which the debug message was generated.
  44  *
  45  * Basically, what that all means is:
  46  *
  47  * - A debugging log file is made up of debug messages.
  48  *
  49  * - Each debug message is made up of a header and text.  The header is
  50  *   separated from the text by a newline.
  51  *
  52  * - The header begins with the timestamp and debug level of the message
  53  *   enclosed in brackets.  The filename and function from which the
  54  *   message was generated may follow.  The filename is terminated by a
  55  *   colon, and the function name is terminated by parenthesis.
  56  *
  57  * - The message text is made up of zero or more lines, each terminated by
  58  *   a newline.
  59  */
  60
  61 /* -------------------------------------------------------------------------- **
  62  * External variables.
  63  *
  64  *  dbf           - Global debug file handle.
  65  *  debugf        - Debug file name.
  66  *  append_log    - If True, then the output file will be opened in append
  67  *                  mode.
  68  *  DEBUGLEVEL    - System-wide debug message limit.  Messages with message-
  69  *                  levels higher than DEBUGLEVEL will not be processed.
  70  */
  71
  72 FILE   *dbf        = NULL;
  73 pstring debugf     = "";
  74 BOOL    append_log = False;
  75 int     DEBUGLEVEL = 1;
  76
  77
  78 /* -------------------------------------------------------------------------- **
  79  * Internal variables.
  80  *
  81  *  stdout_logging  - Default False, if set to True then dbf will be set to
  82  *                    stdout and debug output will go to dbf only, and not
  83  *                    to syslog.  Set in setup_logging() and read in Debug1().
  84  *
  85  *  debug_count     - Number of debug messages that have been output.
  86  *                    Used to check log size.
  87  *
  88  *  syslog_level    - Internal copy of the message debug level.  Written by
  89  *                    dbghdr() and read by Debug1().
  90  *
  91  *  format_bufr     - Used to format debug messages.  The dbgtext() function
  92  *                    prints debug messages to a string, and then passes the
  93  *                    string to format_debug_text(), which uses format_bufr
  94  *                    to build the formatted output.
  95  *
  96  *  format_pos      - Marks the first free byte of the format_bufr.
  97  */
  98
  99 static BOOL    stdout_logging = False;
 100 static int     debug_count    = 0;
 101 static int     syslog_level   = 0;
 102 static pstring format_bufr    = { '\0' };
 103 static int     format_pos     = 0;
 104
 105
 106 /* -------------------------------------------------------------------------- **
 107  * Functions...
 108  */
 109
 110 #if defined(SIGUSR2)
 111 /* ************************************************************************** **
 112  * catch a sigusr2 - decrease the debug log level.
 113  * ************************************************************************** **
 114  */
 115 int sig_usr2( void )
 116   {
 117   BlockSignals( True, SIGUSR2 );
 118
 119   DEBUGLEVEL--;
 120   if( DEBUGLEVEL < 0 )
 121     DEBUGLEVEL = 0;
 122
 123   DEBUG( 0, ( "Got SIGUSR2; set debug level to %d.\n", DEBUGLEVEL ) );
 124
 125   BlockSignals( False, SIGUSR2 );
 126   CatchSignal( SIGUSR2, SIGNAL_CAST sig_usr2 );
 127
 128   return( 0 );
 129   } /* sig_usr2 */
 130 #endif /* SIGUSR2 */
 131
 132 #if defined(SIGUSR1)
 133 /* ************************************************************************** **
 134  * catch a sigusr1 - increase the debug log level.
 135  * ************************************************************************** **
 136  */
 137 int sig_usr1( void )
 138   {
 139   BlockSignals( True, SIGUSR1 );
 140
 141   DEBUGLEVEL++;
 142
 143   if( DEBUGLEVEL > 10 )
 144     DEBUGLEVEL = 10;
 145
 146   DEBUG( 0, ( "Got SIGUSR1; set debug level to %d.\n", DEBUGLEVEL ) );
 147
 148   BlockSignals( False, SIGUSR1 );
 149   CatchSignal( SIGUSR1, SIGNAL_CAST sig_usr1 );
 150
 151   return( 0 );
 152   } /* sig_usr1 */
 153 #endif /* SIGUSR1 */
 154
 155
 156 /* ************************************************************************** **
 157  * get ready for syslog stuff
 158  * ************************************************************************** **
 159  */
 160 void setup_logging( char *pname, BOOL interactive )
 161   {
 162   if( interactive )
 163     {
 164     stdout_logging = True;
 165     dbf = stdout;
 166     }
 167 #ifdef WITH_SYSLOG
 168   else
 169     {
 170     char *p = strrchr( pname,'/' );
 171
 172     if( p )
 173       pname = p + 1;
 174 #ifdef LOG_DAEMON
 175     openlog( pname, LOG_PID, SYSLOG_FACILITY );
 176 #else /* for old systems that have no facility codes. */
 177     openlog( pname, LOG_PID );
 178 #endif
 179     }
 180 #endif
 181   } /* setup_logging */
 182
 183 /* ************************************************************************** **
 184  * reopen the log files
 185  * ************************************************************************** **
 186  */
 187 void reopen_logs( void )
 188   {
 189   pstring fname;
 190
 191   if( DEBUGLEVEL > 0 )
 192     {
 193     pstrcpy( fname, debugf );
 194     if( lp_loaded() && (*lp_logfile()) )
 195       pstrcpy( fname, lp_logfile() );
 196
 197     if( !strcsequal( fname, debugf ) || !dbf || !file_exist( debugf, NULL ) )
 198       {
 199       int oldumask = umask( 022 );
 200
 201       pstrcpy( debugf, fname );
 202       if( dbf )
 203         (void)fclose( dbf );
 204       if( append_log )
 205         dbf = fopen( debugf, "a" );
 206       else
 207         dbf = fopen( debugf, "w" );
 208       /* Fix from klausr@ITAP.Physik.Uni-Stuttgart.De
 209        * to fix problem where smbd's that generate less
 210        * than 100 messages keep growing the log.
 211        */
 212       force_check_log_size();
 213       if( dbf )
 214         setbuf( dbf, NULL );
 215       (void)umask( oldumask );
 216       }
 217     }
 218   else
 219     {
 220     if( dbf )
 221       {
 222       (void)fclose( dbf );
 223       dbf = NULL;
 224       }
 225     }
 226   } /* reopen_logs */
 227
 228 /* ************************************************************************** **
 229  * Force a check of the log size.
 230  * ************************************************************************** **
 231  */
 232 void force_check_log_size( void )
 233   {
 234   debug_count = 100;
 235   } /* force_check_log_size */
 236
 237 /* ************************************************************************** **
 238  * Check to see if the log has grown to be too big.
 239  * ************************************************************************** **
 240  */
 241 static void check_log_size( void )
 242   {
 243   int         maxlog;
 244   struct stat st;
 245
 246   if( debug_count++ < 100 || getuid() != 0 )
 247     return;
 248
 249   maxlog = lp_max_log_size() * 1024;
 250   if( !dbf || maxlog <= 0 )
 251     return;
 252
 253   if( fstat( fileno( dbf ), &st ) == 0 && st.st_size > maxlog )
 254     {
 255     (void)fclose( dbf );
 256     dbf = NULL;
 257     reopen_logs();
 258     if( dbf && file_size( debugf ) > maxlog )
 259       {
 260       pstring name;
 261
 262       (void)fclose( dbf );
 263       dbf = NULL;
 264       slprintf( name, sizeof(name)-1, "%s.old", debugf );
 265       (void)rename( debugf, name );
 266       reopen_logs();
 267       }
 268     }
 269   debug_count = 0;
 270   } /* check_log_size */
 271
 272 /* ************************************************************************** **
 273  * Write an debug message on the debugfile.
 274  * This is called by dbghdr() and format_debug_text().
 275  * ************************************************************************** **
 276  */
 277 #ifdef HAVE_STDARG_H
 278  int Debug1( char *format_str, ... )
 279 {
 280 #else
 281  int Debug1(va_alist)
 282 va_dcl
 283 {
 284   char *format_str;
 285 #endif
 286   va_list ap;
 287   int old_errno = errno;
 288
 289   if( stdout_logging )
 290     {
 291 #ifdef HAVE_STDARG_H
 292     va_start( ap, format_str );
 293 #else
 294     va_start( ap );
 295     format_str = va_arg( ap, char * );
 296 #endif
 297     (void)vfprintf( dbf, format_str, ap );
 298     va_end( ap );
 299     errno = old_errno;
 300     return( 0 );
 301     }
 302
 303 #ifdef WITH_SYSLOG
 304   if( !lp_syslog_only() )
 305 #endif
 306     {
 307     if( !dbf )
 308       {
 309       int oldumask = umask( 022 );
 310
 311       if( append_log )
 312         dbf = fopen( debugf, "a" );
 313       else
 314         dbf = fopen( debugf, "w" );
 315       (void)umask( oldumask );
 316       if( dbf )
 317         {
 318         setbuf( dbf, NULL );
 319         }
 320       else
 321         {
 322         errno = old_errno;
 323         return(0);
 324         }
 325       }
 326     }
 327
 328 #ifdef WITH_SYSLOG
 329   if( syslog_level < lp_syslog() )
 330     {
 331     /* map debug levels to syslog() priorities
 332      * note that not all DEBUG(0, ...) calls are
 333      * necessarily errors
 334      */
 335     static int priority_map[] = {
 336       LOG_ERR,     /* 0 */
 337       LOG_WARNING, /* 1 */
 338       LOG_NOTICE,  /* 2 */
 339       LOG_INFO,    /* 3 */
 340       };
 341     int     priority;
 342     pstring msgbuf;
 343
 344     if( syslog_level >= ( sizeof(priority_map) / sizeof(priority_map[0]) )
 345      || syslog_level < 0)
 346       priority = LOG_DEBUG;
 347     else
 348       priority = priority_map[syslog_level];
 349
 350 #ifdef HAVE_STDARG_H
 351     va_start( ap, format_str );
 352 #else
 353     va_start( ap );
 354     format_str = va_arg( ap, char * );
 355 #endif
 356     vslprintf( msgbuf, sizeof(msgbuf)-1, format_str, ap );
 357     va_end( ap );
 358
 359     msgbuf[255] = '\0';
 360     syslog( priority, "%s", msgbuf );
 361     }
 362 #endif
 363
 364 #ifdef WITH_SYSLOG
 365   if( !lp_syslog_only() )
 366 #endif
 367     {
 368 #ifdef HAVE_STDARG_H
 369     va_start( ap, format_str );
 370 #else
 371     va_start( ap );
 372     format_str = va_arg( ap, char * );
 373 #endif
 374     (void)vfprintf( dbf, format_str, ap );
 375     va_end( ap );
 376     (void)fflush( dbf );
 377     }
 378
 379   check_log_size();
 380
 381   errno = old_errno;
 382
 383   return( 0 );
 384   } /* Debug1 */
 385
 386
 387 /* ************************************************************************** **
 388  * Print the buffer content via Debug1(), then reset the buffer.
 389  *
 390  *  Input:  none
 391  *  Output: none
 392  *
 393  * ************************************************************************** **
 394  */
 395 static void bufr_print( void )
 396   {
 397   format_bufr[format_pos] = '\0';
 398   (void)Debug1( "%s", format_bufr );
 399   format_pos = 0;
 400   } /* bufr_print */
 401
 402 /* ************************************************************************** **
 403  * Format the debug message text.
 404  *
 405  *  Input:  msg - Text to be added to the "current" debug message text.
 406  *
 407  *  Output: none.
 408  *
 409  *  Notes:  The purpose of this is two-fold.  First, each call to syslog()
 410  *          (used by Debug1(), see above) generates a new line of syslog
 411  *          output.  This is fixed by storing the partial lines until the
 412  *          newline character is encountered.  Second, printing the debug
 413  *          message lines when a newline is encountered allows us to add
 414  *          spaces, thus indenting the body of the message and making it
 415  *          more readable.
 416  *
 417  * ************************************************************************** **
 418  */
 419 static void format_debug_text( char *msg )
 420   {
 421   int max = sizeof( format_bufr ) - 1;
 422   int i;
 423
 424   for( i = 0; msg[i]; i++ )
 425     {
 426     /* Indent two spaces at each new line. */
 427     if( 0 == format_pos )
 428       {
 429       format_bufr[0] = format_bufr[1] = ' ';
 430       format_pos = 2;
 431       }
 432
 433     /* If there's room, copy the character to the format buffer. */
 434     if( format_pos < max )
 435       format_bufr[format_pos++] = msg[i];
 436
 437     /* If a newline is encountered, print & restart. */
 438     if( '\n' == msg[i] )
 439       bufr_print();
 440     }
 441
 442   /* Just to be safe... */
 443   format_bufr[format_pos] = '\0';
 444   } /* format_debug_text */
 445
 446 /* ************************************************************************** **
 447  * Flush debug output, including the format buffer content.
 448  *
 449  *  Input:  none
 450  *  Output: none
 451  *
 452  * ************************************************************************** **
 453  */
 454 void dbgflush( void )
 455   {
 456   bufr_print();
 457   (void)fflush( dbf );
 458   } /* dbgflush */
 459
 460 /* ************************************************************************** **
 461  * Print a Debug Header.
 462  *
 463  *  Input:  level - Debug level of the message (not the system-wide debug
 464  *                  level.
 465  *          file  - Pointer to a string containing the name of the file
 466  *                  from which this function was called, or an empty string
 467  *                  if the __FILE__ macro is not implemented.
 468  *          func  - Pointer to a string containing the name of the function
 469  *                  from which this function was called, or an empty string
 470  *                  if the __FUNCTION__ macro is not implemented.
 471  *          line  - line number of the call to dbghdr, assuming __LINE__
 472  *                  works.
 473  *
 474  *  Output: Always True.  This makes it easy to fudge a call to dbghdr()
 475  *          in a macro, since the function can be called as part of a test.
 476  *          Eg: ( (level <= DEBUGLEVEL) && (dbghdr(level,"",line)) )
 477  *
 478  *  Notes:  This function takes care of setting syslog_level.
 479  *
 480  * ************************************************************************** **
 481  */
 482 BOOL dbghdr( int level, char *file, char *func, int line )
 483   {
 484   if( format_pos )
 485     {
 486     /* This is a fudge.  If there is stuff sitting in the format_bufr, then
 487      * the *right* thing to do is to call
 488      *   format_debug_text( "\n" );
 489      * to write the remainder, and then proceed with the new header.
 490      * Unfortunately, there are several places in the code at which
 491      * the DEBUG() macro is used to build partial lines.  That in mind,
 492      * we'll work under the assumption that an incomplete line indicates
 493      * that a new header is *not* desired.
 494      */
 495     return( True );
 496     }
 497
 498   /* Set syslog_level. */
 499   syslog_level = level;
 500
 501   /* Don't print a header if we're logging to stdout. */
 502   if( stdout_logging )
 503     return( True );
 504
 505   /* Print the header if timestamps are turned on.  If parameters are
 506    * not yet loaded, then default to timestamps on.
 507    */
 508   if( lp_timestamp_logs() || !(lp_loaded()) )
 509     {
 510     /* Print it all out at once to prevent split syslog output. */
 511     (void)Debug1( "[%s, %d] %s:%s(%d)\n",
 512                   timestring(), level, file, func, line );
 513     }
 514
 515   return( True );
 516   } /* dbghdr */
 517
 518 /* ************************************************************************** **
 519  * Add text to the body of the "current" debug message via the format buffer.
 520  *
 521  *  Input:  format_str  - Format string, as used in printf(), et. al.
 522  *          ...         - Variable argument list.
 523  *
 524  *  ..or..  va_alist    - Old style variable parameter list starting point.
 525  *
 526  *  Output: Always True.  See dbghdr() for more info, though this is not
 527  *          likely to be used in the same way.
 528  *
 529  * ************************************************************************** **
 530  */
 531 #ifdef HAVE_STDARG_H
 532  BOOL dbgtext( char *format_str, ... )
 533   {
 534   va_list ap;
 535   pstring msgbuf;
 536
 537   va_start( ap, format_str );
 538   vslprintf( msgbuf, sizeof(msgbuf)-1, format_str, ap );
 539   va_end( ap );
 540
 541   format_debug_text( msgbuf );
 542
 543   return( True );
 544   } /* dbgtext */
 545
 546 #else
 547  BOOL dbgtext( va_alist )
 548  va_dcl
 549   {
 550   char *format_str;
 551   va_list ap;
 552   pstring msgbuf;
 553
 554   va_start( ap );
 555   format_str = va_arg( ap, char * );
 556   vslprintf( msgbuf, sizeof(msgbuf)-1, format_str, ap );
 557   va_end( ap );
 558
 559   format_debug_text( msgbuf );
 560
 561   return( True );
 562   } /* dbgtext */
 563
 564 #endif
 565
 566 /* ************************************************************************** */