scheduler/log.c

   1 /*
   2  * "$Id: log.c 7699 2008-06-27 20:44:23Z mike $"
   3  *
   4  *   Log file routines for the Common UNIX Printing System (CUPS).
   5  *
   6  *   Copyright 2007-2008 by Apple Inc.
   7  *   Copyright 1997-2007 by Easy Software Products, all rights reserved.
   8  *
   9  *   These coded instructions, statements, and computer programs are the
  10  *   property of Apple Inc. and are protected by Federal copyright
  11  *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  12  *   which should have been included with this file.  If this file is
  13  *   file is missing or damaged, see the license at "http://www.cups.org/".
  14  *
  15  * Contents:
  16  *
  17  *   cupsdGetDateTime()   - Returns a pointer to a date/time string.
  18  *   cupsdLogGSSMessage() - Log a GSSAPI error...
  19  *   cupsdLogJob()        - Log a job message.
  20  *   cupsdLogMessage()    - Log a message to the error log file.
  21  *   cupsdLogPage()       - Log a page to the page log file.
  22  *   cupsdLogRequest()    - Log an HTTP request in Common Log Format.
  23  *   cupsdWriteErrorLog() - Write a line to the ErrorLog.
  24  *   check_log_file()     - Open/rotate a log file if it needs it.
  25  *   format_log_line()    - Format a line for a log file.
  26  */
  27
  28 /*
  29  * Include necessary headers...
  30  */
  31
  32 #include "cupsd.h"
  33 #include <stdarg.h>
  34 #include <syslog.h>
  35
  36
  37 /*
  38  * Local globals...
  39  */
  40
  41 static int      log_linesize = 0;       /* Size of line for output file */
  42 static char     *log_line = NULL;       /* Line for output file */
  43
  44
  45 /*
  46  * Local functions...
  47  */
  48
  49 static int      check_log_file(cups_file_t **lf, const char *logname);
  50 static char     *format_log_line(const char *message, va_list ap);
  51
  52
  53 /*
  54  * 'cupsdGetDateTime()' - Returns a pointer to a date/time string.
  55  */
  56
  57 char *                                  /* O - Date/time string */
  58 cupsdGetDateTime(time_t t)              /* I - Time value */
  59 {
  60   struct tm     *date;                  /* Date/time value */
  61   static time_t last_time = -1;         /* Last time value */
  62   static char   s[1024];                /* Date/time string */
  63   static const char * const months[12] =/* Months */
  64                 {
  65                   "Jan",
  66                   "Feb",
  67                   "Mar",
  68                   "Apr",
  69                   "May",
  70                   "Jun",
  71                   "Jul",
  72                   "Aug",
  73                   "Sep",
  74                   "Oct",
  75                   "Nov",
  76                   "Dec"
  77                 };
  78
  79
  80  /*
  81   * Make sure we have a valid time...
  82   */
  83
  84   if (!t)
  85     t = time(NULL);
  86
  87   if (t != last_time)
  88   {
  89     last_time = t;
  90
  91    /*
  92     * Get the date and time from the UNIX time value, and then format it
  93     * into a string.  Note that we *can't* use the strftime() function since
  94     * it is localized and will seriously confuse automatic programs if the
  95     * month names are in the wrong language!
  96     *
  97     * Also, we use the "timezone" variable that contains the current timezone
  98     * offset from GMT in seconds so that we are reporting local time in the
  99     * log files.  If you want GMT, set the TZ environment variable accordingly
 100     * before starting the scheduler.
 101     *
 102     * (*BSD and Darwin store the timezone offset in the tm structure)
 103     */
 104
 105     date = localtime(&t);
 106
 107     snprintf(s, sizeof(s), "[%02d/%s/%04d:%02d:%02d:%02d %+03ld%02ld]",
 108              date->tm_mday, months[date->tm_mon], 1900 + date->tm_year,
 109              date->tm_hour, date->tm_min, date->tm_sec,
 110 #ifdef HAVE_TM_GMTOFF
 111              date->tm_gmtoff / 3600, (date->tm_gmtoff / 60) % 60);
 112 #else
 113              timezone / 3600, (timezone / 60) % 60);
 114 #endif /* HAVE_TM_GMTOFF */
 115   }
 116
 117   return (s);
 118 }
 119
 120
 121 #ifdef HAVE_GSSAPI
 122 /*
 123  * 'cupsdLogGSSMessage()' - Log a GSSAPI error...
 124  */
 125
 126 int                                     /* O - 1 on success, 0 on error */
 127 cupsdLogGSSMessage(
 128     int        level,                   /* I - Log level */
 129     int        major_status,            /* I - Major GSSAPI status */
 130     int        minor_status,            /* I - Minor GSSAPI status */
 131     const char *message,                /* I - printf-style message string */
 132     ...)                                /* I - Additional args as needed */
 133 {
 134   OM_uint32     err_major_status,       /* Major status code for display */
 135                 err_minor_status;       /* Minor status code for display */
 136   OM_uint32     msg_ctx;                /* Message context */
 137   gss_buffer_desc major_status_string = GSS_C_EMPTY_BUFFER,
 138                                         /* Major status message */
 139                 minor_status_string = GSS_C_EMPTY_BUFFER;
 140                                         /* Minor status message */
 141   int           ret;                    /* Return value */
 142
 143
 144   msg_ctx             = 0;
 145   err_major_status    = gss_display_status(&err_minor_status,
 146                                            major_status,
 147                                            GSS_C_GSS_CODE,
 148                                            GSS_C_NO_OID,
 149                                            &msg_ctx,
 150                                            &major_status_string);
 151
 152   if (!GSS_ERROR(err_major_status))
 153     err_major_status = gss_display_status(&err_minor_status,
 154                                           minor_status,
 155                                           GSS_C_MECH_CODE,
 156                                           GSS_C_NULL_OID,
 157                                           &msg_ctx,
 158                                           &minor_status_string);
 159
 160   ret = cupsdLogMessage(level, "%s: %s, %s", message,
 161                         (char *)major_status_string.value,
 162                         (char *)minor_status_string.value);
 163   gss_release_buffer(&err_minor_status, &major_status_string);
 164   gss_release_buffer(&err_minor_status, &minor_status_string);
 165
 166   return (ret);
 167 }
 168 #endif /* HAVE_GSSAPI */
 169
 170
 171 /*
 172  * 'cupsdLogJob()' - Log a job message.
 173  */
 174
 175 int                                     /* O - 1 on success, 0 on error */
 176 cupsdLogJob(cupsd_job_t *job,           /* I - Job */
 177             int         level,          /* I - Log level */
 178             const char  *message,       /* I - Printf-style message string */
 179             ...)                        /* I - Additional arguments as needed */
 180 {
 181   va_list               ap;             /* Argument pointer */
 182   char                  jobmsg[1024],   /* Format string for job message */
 183                         *line;          /* Message line */
 184
 185
 186  /*
 187   * See if we want to log this message...
 188   */
 189
 190   if (TestConfigFile || level > LogLevel || !ErrorLog)
 191     return (1);
 192
 193  /*
 194   * Format and write the log message...
 195   */
 196
 197   snprintf(jobmsg, sizeof(jobmsg), "[Job %d] %s", job->id, message);
 198
 199   va_start(ap, message);
 200   line = format_log_line(jobmsg, ap);
 201   va_end(ap);
 202
 203   if (line)
 204     return (cupsdWriteErrorLog(level, line));
 205   else
 206     return (cupsdWriteErrorLog(CUPSD_LOG_ERROR,
 207                                "Unable to allocate memory for log line!"));
 208 }
 209
 210
 211 /*
 212  * 'cupsdLogMessage()' - Log a message to the error log file.
 213  */
 214
 215 int                                     /* O - 1 on success, 0 on error */
 216 cupsdLogMessage(int        level,       /* I - Log level */
 217                 const char *message,    /* I - printf-style message string */
 218                 ...)                    /* I - Additional args as needed */
 219 {
 220   va_list               ap;             /* Argument pointer */
 221   char                  *line;          /* Message line */
 222
 223
 224  /*
 225   * See if we want to log this message...
 226   */
 227
 228   if (TestConfigFile)
 229   {
 230     if (level <= CUPSD_LOG_WARN)
 231     {
 232       va_start(ap, message);
 233       vfprintf(stderr, message, ap);
 234       putc('\n', stderr);
 235       va_end(ap);
 236     }
 237
 238     return (1);
 239   }
 240
 241   if (level > LogLevel || !ErrorLog)
 242     return (1);
 243
 244  /*
 245   * Format and write the log message...
 246   */
 247
 248   va_start(ap, message);
 249   line = format_log_line(message, ap);
 250   va_end(ap);
 251
 252   if (line)
 253     return (cupsdWriteErrorLog(level, line));
 254   else
 255     return (cupsdWriteErrorLog(CUPSD_LOG_ERROR,
 256                                "Unable to allocate memory for log line!"));
 257 }
 258
 259
 260 /*
 261  * 'cupsdLogPage()' - Log a page to the page log file.
 262  */
 263
 264 int                                     /* O - 1 on success, 0 on error */
 265 cupsdLogPage(cupsd_job_t *job,          /* I - Job being printed */
 266              const char  *page)         /* I - Page being printed */
 267 {
 268   int                   i;              /* Looping var */
 269   char                  buffer[2048],   /* Buffer for page log */
 270                         *bufptr,        /* Pointer into buffer */
 271                         name[256];      /* Attribute name */
 272   const char            *format,        /* Pointer into PageLogFormat */
 273                         *nameend;       /* End of attribute name */
 274   ipp_attribute_t       *attr;          /* Current attribute */
 275   int                   number;         /* Page number */
 276   char                  copies[256];    /* Number of copies */
 277
 278
 279  /*
 280   * Format the line going into the page log...
 281   */
 282
 283   if (!PageLogFormat)
 284     return (1);
 285
 286   number = 1;
 287   strcpy(copies, "1");
 288   sscanf(page, "%d%255s", &number, copies);
 289
 290   for (format = PageLogFormat, bufptr = buffer; *format; format ++)
 291   {
 292     if (*format == '%')
 293     {
 294       format ++;
 295
 296       switch (*format)
 297       {
 298         case '%' :                      /* Literal % */
 299             if (bufptr < (buffer + sizeof(buffer) - 1))
 300               *bufptr++ = '%';
 301             break;
 302
 303         case 'p' :                      /* Printer name */
 304             strlcpy(bufptr, job->printer->name,
 305                     sizeof(buffer) - (bufptr - buffer));
 306             bufptr += strlen(bufptr);
 307             break;
 308
 309         case 'j' :                      /* Job ID */
 310             snprintf(bufptr, sizeof(buffer) - (bufptr - buffer), "%d", job->id);
 311             bufptr += strlen(bufptr);
 312             break;
 313
 314         case 'u' :                      /* Username */
 315             strlcpy(bufptr, job->username ? job->username : "-",
 316                     sizeof(buffer) - (bufptr - buffer));
 317             bufptr += strlen(bufptr);
 318             break;
 319
 320         case 'T' :                      /* Date and time */
 321             strlcpy(bufptr, cupsdGetDateTime(time(NULL)),
 322                     sizeof(buffer) - (bufptr - buffer));
 323             bufptr += strlen(bufptr);
 324             break;
 325
 326         case 'P' :                      /* Page number */
 327             snprintf(bufptr, sizeof(buffer) - (bufptr - buffer), "%d", number);
 328             bufptr += strlen(bufptr);
 329             break;
 330
 331         case 'C' :                      /* Number of copies */
 332             strlcpy(bufptr, copies, sizeof(buffer) - (bufptr - buffer));
 333             bufptr += strlen(bufptr);
 334             break;
 335
 336         case '{' :                      /* {attribute} */
 337             if ((nameend = strchr(format, '}')) != NULL &&
 338                 (nameend - format - 2) < (sizeof(name) - 1))
 339             {
 340              /*
 341               * Pull the name from inside the brackets...
 342               */
 343
 344               memcpy(name, format + 1, nameend - format - 1);
 345               name[nameend - format - 1] = '\0';
 346
 347               format = nameend;
 348
 349               if ((attr = ippFindAttribute(job->attrs, name,
 350                                            IPP_TAG_ZERO)) != NULL)
 351               {
 352                /*
 353                 * Add the attribute value...
 354                 */
 355
 356                 for (i = 0;
 357                      i < attr->num_values &&
 358                          bufptr < (buffer + sizeof(buffer) - 1);
 359                      i ++)
 360                 {
 361                   if (i)
 362                     *bufptr++ = ',';
 363
 364                   switch (attr->value_tag)
 365                   {
 366                     case IPP_TAG_INTEGER :
 367                     case IPP_TAG_ENUM :
 368                         snprintf(bufptr, sizeof(buffer) - (bufptr - buffer),
 369                                  "%d", attr->values[i].integer);
 370                         bufptr += strlen(bufptr);
 371                         break;
 372
 373                     case IPP_TAG_BOOLEAN :
 374                         snprintf(bufptr, sizeof(buffer) - (bufptr - buffer),
 375                                  "%d", attr->values[i].boolean);
 376                         bufptr += strlen(bufptr);
 377                         break;
 378
 379                     case IPP_TAG_TEXTLANG :
 380                     case IPP_TAG_NAMELANG :
 381                     case IPP_TAG_TEXT :
 382                     case IPP_TAG_NAME :
 383                     case IPP_TAG_KEYWORD :
 384                     case IPP_TAG_URI :
 385                     case IPP_TAG_URISCHEME :
 386                     case IPP_TAG_CHARSET :
 387                     case IPP_TAG_LANGUAGE :
 388                     case IPP_TAG_MIMETYPE :
 389                         strlcpy(bufptr, attr->values[i].string.text,
 390                                 sizeof(buffer) - (bufptr - buffer));
 391                         bufptr += strlen(bufptr);
 392                         break;
 393
 394                     default :
 395                         strlcpy(bufptr, "???",
 396                                 sizeof(buffer) - (bufptr - buffer));
 397                         bufptr += strlen(bufptr);
 398                         break;
 399                   }
 400                 }
 401               }
 402               else if (bufptr < (buffer + sizeof(buffer) - 1))
 403                 *bufptr++ = '-';
 404               break;
 405             }
 406
 407         default :
 408             if (bufptr < (buffer + sizeof(buffer) - 2))
 409             {
 410               *bufptr++ = '%';
 411               *bufptr++ = *format;
 412             }
 413             break;
 414       }
 415     }
 416     else if (bufptr < (buffer + sizeof(buffer) - 1))
 417       *bufptr++ = *format;
 418   }
 419
 420   *bufptr = '\0';
 421
 422 #ifdef HAVE_VSYSLOG
 423  /*
 424   * See if we are logging pages via syslog...
 425   */
 426
 427   if (!strcmp(PageLog, "syslog"))
 428   {
 429     syslog(LOG_INFO, "%s", buffer);
 430
 431     return (1);
 432   }
 433 #endif /* HAVE_VSYSLOG */
 434
 435  /*
 436   * Not using syslog; check the log file...
 437   */
 438
 439   if (!check_log_file(&PageFile, PageLog))
 440     return (0);
 441
 442  /*
 443   * Print a page log entry of the form:
 444   *
 445   *    printer user job-id [DD/MON/YYYY:HH:MM:SS +TTTT] page num-copies \
 446   *        billing hostname
 447   */
 448
 449   cupsFilePrintf(PageFile, "%s\n", buffer);
 450   cupsFileFlush(PageFile);
 451
 452   return (1);
 453 }
 454
 455
 456 /*
 457  * 'cupsdLogRequest()' - Log an HTTP request in Common Log Format.
 458  */
 459
 460 int                                     /* O - 1 on success, 0 on error */
 461 cupsdLogRequest(cupsd_client_t *con,    /* I - Request to log */
 462                 http_status_t  code)    /* I - Response code */
 463 {
 464   char  temp[2048];                     /* Temporary string for URI */
 465   static const char * const states[] =  /* HTTP client states... */
 466                 {
 467                   "WAITING",
 468                   "OPTIONS",
 469                   "GET",
 470                   "GET",
 471                   "HEAD",
 472                   "POST",
 473                   "POST",
 474                   "POST",
 475                   "PUT",
 476                   "PUT",
 477                   "DELETE",
 478                   "TRACE",
 479                   "CLOSE",
 480                   "STATUS"
 481                 };
 482
 483
 484 #ifdef HAVE_VSYSLOG
 485  /*
 486   * See if we are logging accesses via syslog...
 487   */
 488
 489   if (!strcmp(AccessLog, "syslog"))
 490   {
 491     syslog(LOG_INFO,
 492            "REQUEST %s - %s \"%s %s HTTP/%d.%d\" %d " CUPS_LLFMT " %s %s\n",
 493            con->http.hostname, con->username[0] != '\0' ? con->username : "-",
 494            states[con->operation], _httpEncodeURI(temp, con->uri, sizeof(temp)),
 495            con->http.version / 100, con->http.version % 100,
 496            code, CUPS_LLCAST con->bytes,
 497            con->request ?
 498                ippOpString(con->request->request.op.operation_id) : "-",
 499            con->response ?
 500                ippErrorString(con->response->request.status.status_code) : "-");
 501
 502     return (1);
 503   }
 504 #endif /* HAVE_VSYSLOG */
 505
 506  /*
 507   * Not using syslog; check the log file...
 508   */
 509
 510   if (!check_log_file(&AccessFile, AccessLog))
 511     return (0);
 512
 513  /*
 514   * Write a log of the request in "common log format"...
 515   */
 516
 517   cupsFilePrintf(AccessFile,
 518                  "%s - %s %s \"%s %s HTTP/%d.%d\" %d " CUPS_LLFMT " %s %s\n",
 519                  con->http.hostname, con->username[0] != '\0' ? con->username : "-",
 520                  cupsdGetDateTime(con->start), states[con->operation],
 521                  _httpEncodeURI(temp, con->uri, sizeof(temp)),
 522                  con->http.version / 100, con->http.version % 100,
 523                  code, CUPS_LLCAST con->bytes,
 524                  con->request ?
 525                      ippOpString(con->request->request.op.operation_id) : "-",
 526                  con->response ?
 527                      ippErrorString(con->response->request.status.status_code) :
 528                      "-");
 529
 530   cupsFileFlush(AccessFile);
 531
 532   return (1);
 533 }
 534
 535
 536 /*
 537  * 'cupsdWriteErrorLog()' - Write a line to the ErrorLog.
 538  */
 539
 540 int                                     /* O - 1 on success, 0 on failure */
 541 cupsdWriteErrorLog(int        level,    /* I - Log level */
 542                    const char *message) /* I - Message string */
 543 {
 544   static const char     levels[] =      /* Log levels... */
 545                 {
 546                   ' ',
 547                   'X',
 548                   'A',
 549                   'C',
 550                   'E',
 551                   'W',
 552                   'N',
 553                   'I',
 554                   'D',
 555                   'd'
 556                 };
 557 #ifdef HAVE_VSYSLOG
 558   static const int      syslevels[] =   /* SYSLOG levels... */
 559                 {
 560                   0,
 561                   LOG_EMERG,
 562                   LOG_ALERT,
 563                   LOG_CRIT,
 564                   LOG_ERR,
 565                   LOG_WARNING,
 566                   LOG_NOTICE,
 567                   LOG_INFO,
 568                   LOG_DEBUG,
 569                   LOG_DEBUG
 570                 };
 571 #endif /* HAVE_VSYSLOG */
 572
 573
 574 #ifdef HAVE_VSYSLOG
 575  /*
 576   * See if we are logging errors via syslog...
 577   */
 578
 579   if (!strcmp(ErrorLog, "syslog"))
 580   {
 581     syslog(syslevels[level], "%s", message);
 582     return (1);
 583   }
 584 #endif /* HAVE_VSYSLOG */
 585
 586  /*
 587   * Not using syslog; check the log file...
 588   */
 589
 590   if (!check_log_file(&ErrorFile, ErrorLog))
 591     return (0);
 592
 593  /*
 594   * Write the log message...
 595   */
 596
 597   cupsFilePrintf(ErrorFile, "%c %s %s\n", levels[level],
 598                  cupsdGetDateTime(time(NULL)), message);
 599   cupsFileFlush(ErrorFile);
 600
 601   return (1);
 602 }
 603
 604
 605 /*
 606  * 'check_log_file()' - Open/rotate a log file if it needs it.
 607  */
 608
 609 static int                              /* O  - 1 if log file open */
 610 check_log_file(cups_file_t **lf,        /* IO - Log file */
 611                const char  *logname)    /* I  - Log filename */
 612 {
 613   char          backname[1024],         /* Backup log filename */
 614                 filename[1024],         /* Formatted log filename */
 615                 *ptr;                   /* Pointer into filename */
 616   const char    *logptr;                /* Pointer into log filename */
 617
 618
 619  /*
 620   * See if we have a log file to check...
 621   */
 622
 623   if (!lf || !logname || !logname[0])
 624     return (1);
 625
 626  /*
 627   * Format the filename as needed...
 628   */
 629
 630   if (!*lf ||
 631       (strncmp(logname, "/dev/", 5) && cupsFileTell(*lf) > MaxLogSize &&
 632        MaxLogSize > 0))
 633   {
 634    /*
 635     * Handle format strings...
 636     */
 637
 638     filename[sizeof(filename) - 1] = '\0';
 639
 640     if (logname[0] != '/')
 641     {
 642       strlcpy(filename, ServerRoot, sizeof(filename));
 643       strlcat(filename, "/", sizeof(filename));
 644     }
 645     else
 646       filename[0] = '\0';
 647
 648     for (logptr = logname, ptr = filename + strlen(filename);
 649          *logptr && ptr < (filename + sizeof(filename) - 1);
 650          logptr ++)
 651       if (*logptr == '%')
 652       {
 653        /*
 654         * Format spec...
 655         */
 656
 657         logptr ++;
 658         if (*logptr == 's')
 659         {
 660          /*
 661           * Insert the server name...
 662           */
 663
 664           strlcpy(ptr, ServerName, sizeof(filename) - (ptr - filename));
 665           ptr += strlen(ptr);
 666         }
 667         else
 668         {
 669          /*
 670           * Otherwise just insert the character...
 671           */
 672
 673           *ptr++ = *logptr;
 674         }
 675       }
 676       else
 677         *ptr++ = *logptr;
 678
 679     *ptr = '\0';
 680   }
 681
 682  /*
 683   * See if the log file is open...
 684   */
 685
 686   if (!*lf)
 687   {
 688    /*
 689     * Nope, open the log file...
 690     */
 691
 692     if ((*lf = cupsFileOpen(filename, "a")) == NULL)
 693     {
 694      /*
 695       * If the file is in CUPS_LOGDIR then try to create a missing directory...
 696       */
 697
 698       if (!strncmp(filename, CUPS_LOGDIR, strlen(CUPS_LOGDIR)))
 699       {
 700         cupsdCheckPermissions(CUPS_LOGDIR, NULL, 0755, RunUser, Group, 1, -1);
 701
 702         *lf = cupsFileOpen(filename, "a");
 703       }
 704
 705       if (*lf == NULL)
 706       {
 707         syslog(LOG_ERR, "Unable to open log file \"%s\" - %s", filename,
 708                strerror(errno));
 709         return (0);
 710       }
 711     }
 712
 713     if (strncmp(filename, "/dev/", 5))
 714     {
 715      /*
 716       * Change ownership and permissions of non-device logs...
 717       */
 718
 719       fchown(cupsFileNumber(*lf), RunUser, Group);
 720       fchmod(cupsFileNumber(*lf), LogFilePerm);
 721     }
 722   }
 723
 724  /*
 725   * Do we need to rotate the log?
 726   */
 727
 728   if (strncmp(logname, "/dev/", 5) && cupsFileTell(*lf) > MaxLogSize &&
 729       MaxLogSize > 0)
 730   {
 731    /*
 732     * Rotate log file...
 733     */
 734
 735     cupsFileClose(*lf);
 736
 737     strcpy(backname, filename);
 738     strlcat(backname, ".O", sizeof(backname));
 739
 740     unlink(backname);
 741     rename(filename, backname);
 742
 743     if ((*lf = cupsFileOpen(filename, "a")) == NULL)
 744     {
 745       syslog(LOG_ERR, "Unable to open log file \"%s\" - %s", filename,
 746              strerror(errno));
 747
 748       return (0);
 749     }
 750
 751    /*
 752     * Change ownership and permissions of non-device logs...
 753     */
 754
 755     fchown(cupsFileNumber(*lf), RunUser, Group);
 756     fchmod(cupsFileNumber(*lf), LogFilePerm);
 757   }
 758
 759   return (1);
 760 }
 761
 762
 763 /*
 764  * 'format_log_line()' - Format a line for a log file.
 765  *
 766  * This function resizes a global string buffer as needed.  Each call returns
 767  * a pointer to this buffer, so the contents are only good until the next call
 768  * to format_log_line()...
 769  */
 770
 771 static char *                           /* O - Text or NULL on error */
 772 format_log_line(const char *message,    /* I - Printf-style format string */
 773                 va_list    ap)          /* I - Argument list */
 774 {
 775   int   len;                            /* Length of formatted line */
 776
 777
 778  /*
 779   * Allocate the line buffer as needed...
 780   */
 781
 782   if (!log_linesize)
 783   {
 784     log_linesize = 8192;
 785     log_line     = malloc(log_linesize);
 786
 787     if (!log_line)
 788       return (NULL);
 789   }
 790
 791  /*
 792   * Format the log message...
 793   */
 794
 795   len = vsnprintf(log_line, log_linesize, message, ap);
 796
 797  /*
 798   * Resize the buffer as needed...
 799   */
 800
 801   if (len >= log_linesize)
 802   {
 803     char        *temp;                  /* Temporary string pointer */
 804
 805
 806     len ++;
 807
 808     if (len < 8192)
 809       len = 8192;
 810     else if (len > 65536)
 811       len = 65536;
 812
 813     temp = realloc(log_line, len);
 814
 815     if (temp)
 816     {
 817       log_line     = temp;
 818       log_linesize = len;
 819     }
 820
 821     len = vsnprintf(log_line, log_linesize, message, ap);
 822   }
 823
 824   return (log_line);
 825 }
 826
 827
 828 /*
 829  * End of "$Id: log.c 7699 2008-06-27 20:44:23Z mike $".
 830  */