lib/util/debug.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba debug functions
   4    Copyright (C) Andrew Tridgell 2003
   5    Copyright (C) James J Myers   2003
   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 3 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, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "system/filesys.h"
  23 #include "system/time.h"
  24 #include "dynconfig/dynconfig.h"
  25
  26 /**
  27  * @file
  28  * @brief Debug logging
  29  **/
  30
  31 /**
  32  * this global variable determines what messages are printed
  33  */
  34 int _debug_level = 0;
  35 _PUBLIC_ int *debug_level = &_debug_level;
  36 static int debug_all_class_hack = 1;
  37 int *DEBUGLEVEL_CLASS = &debug_all_class_hack; /* For samba 3 */
  38 static bool debug_all_class_isset_hack = true;
  39 bool    *DEBUGLEVEL_CLASS_ISSET = &debug_all_class_isset_hack; /* For samba 3 */
  40
  41 /* the registered mutex handlers */
  42 static struct {
  43         const char *name;
  44         struct debug_ops ops;
  45 } debug_handlers;
  46
  47 /* state variables for the debug system */
  48 static struct {
  49         int fd;   /* The log file handle */
  50         enum debug_logtype logtype; /* The type of logging we are doing: eg stdout, file, stderr */
  51         const char *prog_name;
  52         bool reopening_logs;
  53 } state;
  54
  55 static bool reopen_logs_scheduled;
  56 static bool check_reopen_logs(void)
  57 {
  58         if (state.fd == 0 || reopen_logs_scheduled) {
  59                 reopen_logs_scheduled = false;
  60                 reopen_logs();
  61         }
  62
  63         if (state.fd <= 0)
  64                 return false;
  65
  66         return true;
  67 }
  68
  69 _PUBLIC_ void debug_schedule_reopen_logs(void)
  70 {
  71         reopen_logs_scheduled = true;
  72 }
  73
  74 static void log_timestring(int level, const char *location, const char *func)
  75 {
  76         char *t = NULL;
  77         char *s = NULL;
  78
  79         if (!check_reopen_logs()) return;
  80
  81         if (state.logtype != DEBUG_FILE) return;
  82
  83         t = timestring(NULL, time(NULL));
  84         if (!t) return;
  85
  86         asprintf(&s, "[%s, %d %s:%s()]\n", t, level, location, func);
  87         talloc_free(t);
  88         if (!s) return;
  89
  90         write(state.fd, s, strlen(s));
  91         free(s);
  92 }
  93
  94 /**
  95   the backend for debug messages. Note that the DEBUG() macro has already
  96   ensured that the log level has been met before this is called
  97 */
  98 _PUBLIC_ void dbghdr(int level, const char *location, const char *func)
  99 {
 100         log_timestring(level, location, func);
 101         log_task_id();
 102 }
 103
 104
 105 _PUBLIC_ void dbghdrclass(int level, int dclass, const char *location, const char *func)
 106 {
 107         /* Simple wrapper, Samba 4 doesn't do debug classes */
 108         dbghdr(level, location, func);
 109 }
 110
 111 /**
 112   the backend for debug messages. Note that the DEBUG() macro has already
 113   ensured that the log level has been met before this is called
 114
 115   @note You should never have to call this function directly. Call the DEBUG()
 116   macro instead.
 117 */
 118 _PUBLIC_ void dbgtext(const char *format, ...)
 119 {
 120         va_list ap;
 121
 122         if (!check_reopen_logs()) return;
 123
 124         va_start(ap, format);
 125         vdprintf(state.fd, format, ap);
 126         va_end(ap);
 127 }
 128
 129 _PUBLIC_ const char *logfile = NULL;
 130
 131 /**
 132   reopen the log file (usually called because the log file name might have changed)
 133 */
 134 _PUBLIC_ void reopen_logs(void)
 135 {
 136         char *fname = NULL;
 137         int old_fd = state.fd;
 138         if (state.reopening_logs) {
 139                 return;
 140         }
 141
 142         switch (state.logtype) {
 143         case DEBUG_STDOUT:
 144         case DEBUG_DEFAULT_STDOUT:
 145                 state.fd = 1;
 146                 break;
 147
 148         case DEBUG_STDERR:
 149         case DEBUG_DEFAULT_STDERR:
 150                 state.fd = 2;
 151                 break;
 152
 153         case DEBUG_FILE:
 154                 state.reopening_logs = true;
 155                 if (logfile && (*logfile) == '/') {
 156                         fname = strdup(logfile);
 157                 } else {
 158                         asprintf(&fname, "%s/%s.log", dyn_LOGFILEBASE, state.prog_name);
 159                 }
 160                 if (fname) {
 161                         int newfd = open(fname, O_CREAT|O_APPEND|O_WRONLY, 0600);
 162                         if (newfd == -1) {
 163                                 DEBUG(1, ("Failed to open new logfile: %s\n", fname));
 164                                 old_fd = -1;
 165                         } else {
 166                                 state.fd = newfd;
 167                         }
 168                         free(fname);
 169                 } else {
 170                         DEBUG(1, ("Failed to find name for file-based logfile!\n"));
 171                 }
 172                 state.reopening_logs = false;
 173
 174                 break;
 175         }
 176
 177         if (old_fd > 2) {
 178                 close(old_fd);
 179         }
 180 }
 181
 182 /* setup for logging of talloc warnings */
 183 static void talloc_log_fn(const char *msg)
 184 {
 185         DEBUG(0,("%s", msg));
 186 }
 187
 188 void debug_setup_talloc_log(void)
 189 {
 190         talloc_set_log_fn(talloc_log_fn);
 191 }
 192
 193 /**
 194   control the name of the logfile and whether logging will be to stdout, stderr
 195   or a file, and set up syslog
 196
 197   new_log indicates the destination for the debug log (an enum in
 198   order of precedence - once set to DEBUG_FILE, it is not possible to
 199   reset to DEBUG_STDOUT for example.  This makes it easy to override
 200   for debug to stderr on the command line, as the smb.conf cannot
 201   reset it back to file-based logging
 202 */
 203 _PUBLIC_ void setup_logging(const char *prog_name, enum debug_logtype new_logtype)
 204 {
 205         debug_setup_talloc_log();
 206         if (state.logtype < new_logtype) {
 207                 state.logtype = new_logtype;
 208         }
 209         if (prog_name) {
 210                 state.prog_name = prog_name;
 211         }
 212         reopen_logs();
 213 }
 214
 215 /**
 216   return a string constant containing n tabs
 217   no more than 10 tabs are returned
 218 */
 219 _PUBLIC_ const char *do_debug_tab(int n)
 220 {
 221         const char *tabs[] = {"", "\t", "\t\t", "\t\t\t", "\t\t\t\t", "\t\t\t\t\t",
 222                               "\t\t\t\t\t\t", "\t\t\t\t\t\t\t", "\t\t\t\t\t\t\t\t",
 223                               "\t\t\t\t\t\t\t\t\t", "\t\t\t\t\t\t\t\t\t\t"};
 224         return tabs[MIN(n, 10)];
 225 }
 226
 227
 228 /**
 229   log suspicious usage - print comments and backtrace
 230 */
 231 _PUBLIC_ void log_suspicious_usage(const char *from, const char *info)
 232 {
 233         if (!debug_handlers.ops.log_suspicious_usage) return;
 234
 235         debug_handlers.ops.log_suspicious_usage(from, info);
 236 }
 237
 238
 239 /**
 240   print suspicious usage - print comments and backtrace
 241 */
 242 _PUBLIC_ void print_suspicious_usage(const char* from, const char* info)
 243 {
 244         if (!debug_handlers.ops.print_suspicious_usage) return;
 245
 246         debug_handlers.ops.print_suspicious_usage(from, info);
 247 }
 248
 249 _PUBLIC_ uint32_t get_task_id(void)
 250 {
 251         if (debug_handlers.ops.get_task_id) {
 252                 return debug_handlers.ops.get_task_id();
 253         }
 254         return getpid();
 255 }
 256
 257 _PUBLIC_ void log_task_id(void)
 258 {
 259         if (!debug_handlers.ops.log_task_id) return;
 260
 261         if (!check_reopen_logs()) return;
 262
 263         debug_handlers.ops.log_task_id(state.fd);
 264 }
 265
 266 /**
 267   register a set of debug handlers.
 268 */
 269 _PUBLIC_ void register_debug_handlers(const char *name, struct debug_ops *ops)
 270 {
 271         debug_handlers.name = name;
 272         debug_handlers.ops = *ops;
 273 }