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;
  50         enum debug_logtype logtype;
  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                 state.fd = 1;
 145                 break;
 146
 147         case DEBUG_STDERR:
 148                 state.fd = 2;
 149                 break;
 150
 151         case DEBUG_FILE:
 152                 state.reopening_logs = true;
 153                 if (logfile && (*logfile) == '/') {
 154                         fname = strdup(logfile);
 155                 } else {
 156                         asprintf(&fname, "%s/%s.log", dyn_LOGFILEBASE, state.prog_name);
 157                 }
 158                 if (fname) {
 159                         int newfd = open(fname, O_CREAT|O_APPEND|O_WRONLY, 0600);
 160                         if (newfd == -1) {
 161                                 DEBUG(1, ("Failed to open new logfile: %s\n", fname));
 162                                 old_fd = -1;
 163                         } else {
 164                                 state.fd = newfd;
 165                         }
 166                         free(fname);
 167                 } else {
 168                         DEBUG(1, ("Failed to find name for file-based logfile!\n"));
 169                 }
 170                 state.reopening_logs = false;
 171
 172                 break;
 173         }
 174
 175         if (old_fd > 2) {
 176                 close(old_fd);
 177         }
 178 }
 179
 180 /* setup for logging of talloc warnings */
 181 static void talloc_log_fn(const char *msg)
 182 {
 183         DEBUG(0,("%s", msg));
 184 }
 185
 186 void debug_setup_talloc_log(void)
 187 {
 188         talloc_set_log_fn(talloc_log_fn);
 189 }
 190
 191 /**
 192   control the name of the logfile and whether logging will be to stdout, stderr
 193   or a file, and set up syslog
 194
 195   new_log indicates the destination for the debug log (an enum in
 196   order of precedence - once set to DEBUG_FILE, it is not possible to
 197   reset to DEBUG_STDOUT for example.  This makes it easy to override
 198   for debug to stderr on the command line, as the smb.conf cannot
 199   reset it back to file-based logging
 200 */
 201 _PUBLIC_ void setup_logging(const char *prog_name, enum debug_logtype new_logtype)
 202 {
 203         debug_setup_talloc_log();
 204         if (state.logtype < new_logtype) {
 205                 state.logtype = new_logtype;
 206         }
 207         if (prog_name) {
 208                 state.prog_name = prog_name;
 209         }
 210         reopen_logs();
 211 }
 212
 213 /**
 214   return a string constant containing n tabs
 215   no more than 10 tabs are returned
 216 */
 217 _PUBLIC_ const char *do_debug_tab(int n)
 218 {
 219         const char *tabs[] = {"", "\t", "\t\t", "\t\t\t", "\t\t\t\t", "\t\t\t\t\t",
 220                               "\t\t\t\t\t\t", "\t\t\t\t\t\t\t", "\t\t\t\t\t\t\t\t",
 221                               "\t\t\t\t\t\t\t\t\t", "\t\t\t\t\t\t\t\t\t\t"};
 222         return tabs[MIN(n, 10)];
 223 }
 224
 225
 226 /**
 227   log suspicious usage - print comments and backtrace
 228 */
 229 _PUBLIC_ void log_suspicious_usage(const char *from, const char *info)
 230 {
 231         if (!debug_handlers.ops.log_suspicious_usage) return;
 232
 233         debug_handlers.ops.log_suspicious_usage(from, info);
 234 }
 235
 236
 237 /**
 238   print suspicious usage - print comments and backtrace
 239 */
 240 _PUBLIC_ void print_suspicious_usage(const char* from, const char* info)
 241 {
 242         if (!debug_handlers.ops.print_suspicious_usage) return;
 243
 244         debug_handlers.ops.print_suspicious_usage(from, info);
 245 }
 246
 247 _PUBLIC_ uint32_t get_task_id(void)
 248 {
 249         if (debug_handlers.ops.get_task_id) {
 250                 return debug_handlers.ops.get_task_id();
 251         }
 252         return getpid();
 253 }
 254
 255 _PUBLIC_ void log_task_id(void)
 256 {
 257         if (!debug_handlers.ops.log_task_id) return;
 258
 259         if (!check_reopen_logs()) return;
 260
 261         debug_handlers.ops.log_task_id(state.fd);
 262 }
 263
 264 /**
 265   register a set of debug handlers.
 266 */
 267 _PUBLIC_ void register_debug_handlers(const char *name, struct debug_ops *ops)
 268 {
 269         debug_handlers.name = name;
 270         debug_handlers.ops = *ops;
 271 }