src/helper/log.c

   1 /***************************************************************************
   2  *   Copyright (C) 2005 by Dominic Rath                                    *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  19  ***************************************************************************/
  20 #ifdef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include "log.h"
  25 #include "configuration.h"
  26 #include "time_support.h"
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <stdarg.h>
  32 #ifndef _WIN32
  33 #include <malloc.h>
  34 #endif
  35
  36 int debug_level = -1;
  37
  38 static FILE* log_output;
  39 static log_callback_t *log_callbacks = NULL;
  40
  41 static long long start;
  42
  43 static char *log_strings[5] =
  44 {
  45         "User:   ",
  46         "Error:  ",
  47         "Warning:",
  48         "Info:   ",
  49         "Debug:  "
  50 };
  51
  52 static int count = 0;
  53
  54 /* The log_puts() serves to somewhat different goals:
  55  *
  56  * - logging
  57  * - feeding low-level info to the user in GDB or Telnet
  58  *
  59  * The latter dictates that strings without newline are not logged, lest there
  60  * will be *MANY log lines when sending one char at the time(e.g.
  61  * target_request.c).
  62  *
  63  */
  64 static void log_puts(enum log_levels level, const char *file, int line, const char *function, const char *string)
  65 {
  66         char *f;
  67         if (level == LOG_LVL_OUTPUT)
  68         {
  69                 /* do not prepend any headers, just print out what we were given and return */
  70                 fputs(string, log_output);
  71                 fflush(log_output);
  72                 return;
  73         }
  74
  75         f = strrchr(file, '/');
  76         if (f != NULL)
  77                 file = f + 1;
  78
  79         if (strchr(string, '\n')!=NULL)
  80         {
  81                 if (debug_level >= LOG_LVL_DEBUG)
  82                 {
  83                         /* print with count and time information */
  84                         int t=(int)(timeval_ms()-start);
  85 #ifndef _WIN32
  86                         struct mallinfo info;
  87                         info = mallinfo();
  88 #endif
  89                         fprintf(log_output, "%s %d %d %s:%d %s()"
  90 #ifndef _WIN32
  91                                         " %d"
  92 #endif
  93                                         ": %s", log_strings[level+1], count, t, file, line, function,
  94 #ifndef _WIN32
  95                                         info.fordblks,
  96 #endif
  97                                         string);
  98                 }
  99                 else
 100                 {
 101                         /* do not print count and time */
 102                         fprintf(log_output, "%s %s:%d %s(): %s", log_strings[level+1], file, line, function, string);
 103                 }
 104         } else
 105         {
 106                 /* only entire lines are logged. Otherwise it's
 107                  * single chars intended for the log callbacks. */
 108         }
 109
 110         fflush(log_output);
 111
 112         /* Never forward LOG_LVL_DEBUG, too verbose and they can be found in the log if need be */
 113         if (level <= LOG_LVL_INFO)
 114         {
 115                 log_callback_t *cb, *next;
 116                 cb = log_callbacks;
 117                 /* DANGER!!!! the log callback can remove itself!!!! */
 118                 while (cb)
 119                 {
 120                         next=cb->next;
 121                         cb->fn(cb->priv, file, line, function, string);
 122                         cb=next;
 123                 }
 124         }
 125 }
 126
 127 void log_printf(enum log_levels level, const char *file, int line, const char *function, const char *format, ...)
 128 {
 129         char *string;
 130         va_list ap;
 131
 132         count++;
 133         if (level > debug_level)
 134                 return;
 135
 136         va_start(ap, format);
 137
 138         string = alloc_vprintf(format, ap);
 139         if (string != NULL)
 140         {
 141                 log_puts(level, file, line, function, string);
 142                 free(string);
 143         }
 144
 145         va_end(ap);
 146 }
 147
 148 void log_printf_lf(enum log_levels level, const char *file, int line, const char *function, const char *format, ...)
 149 {
 150         char *string;
 151         va_list ap;
 152
 153         count++;
 154         if (level > debug_level)
 155                 return;
 156
 157         va_start(ap, format);
 158
 159         string = alloc_vprintf(format, ap);
 160         if (string != NULL)
 161         {
 162                 strcat(string, "\n"); /* alloc_vprintf guaranteed the buffer to be at least one char longer */
 163                 log_puts(level, file, line, function, string);
 164                 free(string);
 165         }
 166
 167         va_end(ap);
 168 }
 169
 170 /* change the current debug level on the fly
 171  * 0: only ERRORS
 172  * 1: + WARNINGS
 173  * 2: + INFORMATIONAL MSGS
 174  * 3: + DEBUG MSGS
 175  */
 176 int handle_debug_level_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 177 {
 178         if (argc == 0)
 179                 command_print(cmd_ctx, "debug_level: %i", debug_level);
 180
 181         if (argc > 0)
 182                 debug_level = strtoul(args[0], NULL, 0);
 183
 184         if (debug_level < 0)
 185                 debug_level = 0;
 186
 187         if (debug_level > 3)
 188                 debug_level = 3;
 189
 190         return ERROR_OK;
 191 }
 192
 193 int handle_log_output_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 194 {
 195         if (argc == 1)
 196         {
 197                 FILE* file = fopen(args[0], "w");
 198
 199                 if (file)
 200                 {
 201                         log_output = file;
 202                 }
 203         }
 204
 205         return ERROR_OK;
 206 }
 207
 208 int log_register_commands(struct command_context_s *cmd_ctx)
 209 {
 210         start = timeval_ms();
 211         register_command(cmd_ctx, NULL, "log_output", handle_log_output_command,
 212                 COMMAND_ANY, "redirect logging to <file> (default: stderr)");
 213         register_command(cmd_ctx, NULL, "debug_level", handle_debug_level_command,
 214                 COMMAND_ANY, "adjust debug level <0-3>");
 215
 216         return ERROR_OK;
 217 }
 218
 219 int log_init(struct command_context_s *cmd_ctx)
 220 {
 221         /* set defaults for daemon configuration, if not set by cmdline or cfgfile */
 222         if (debug_level == -1)
 223                 debug_level = LOG_LVL_INFO;
 224
 225         if (log_output == NULL)
 226         {
 227                 log_output = stderr;
 228         }
 229
 230         return ERROR_OK;
 231 }
 232
 233 int set_log_output(struct command_context_s *cmd_ctx, FILE *output)
 234 {
 235         log_output = output;
 236         return ERROR_OK;
 237 }
 238
 239 /* add/remove log callback handler */
 240 int log_add_callback(log_callback_fn fn, void *priv)
 241 {
 242         log_callback_t *cb;
 243
 244         /* prevent the same callback to be registered more than once, just for sure */
 245         for (cb = log_callbacks; cb; cb = cb->next)
 246         {
 247                 if (cb->fn == fn && cb->priv == priv)
 248                         return ERROR_INVALID_ARGUMENTS;
 249         }
 250
 251         /* alloc memory, it is safe just to return in case of an error, no need for the caller to check this */
 252         if ((cb = malloc(sizeof(log_callback_t))) == NULL)
 253                 return ERROR_BUF_TOO_SMALL;
 254
 255         /* add item to the beginning of the linked list */
 256         cb->fn = fn;
 257         cb->priv = priv;
 258         cb->next = log_callbacks;
 259         log_callbacks = cb;
 260
 261         return ERROR_OK;
 262 }
 263
 264 int log_remove_callback(log_callback_fn fn, void *priv)
 265 {
 266         log_callback_t *cb, **p;
 267
 268         for (p = &log_callbacks; (cb = *p); p = &(*p)->next)
 269         {
 270                 if (cb->fn == fn && cb->priv == priv)
 271                 {
 272                         *p = cb->next;
 273                         free(cb);
 274                         return ERROR_OK;
 275                 }
 276         }
 277
 278         /* no such item */
 279         return ERROR_INVALID_ARGUMENTS;
 280 }
 281
 282 /* return allocated string w/printf() result */
 283 char *alloc_vprintf(const char *fmt, va_list ap)
 284 {
 285         /* no buffer at the beginning, force realloc to do the job */
 286         char *string = NULL;
 287
 288         /* start with buffer size suitable for typical messages */
 289         int size = 128;
 290
 291         for (;;)
 292         {
 293                 char *t = string;
 294                 va_list ap_copy;
 295                 int ret;
 296                 string = realloc(string, size);
 297                 if (string == NULL)
 298                 {
 299                         if (t != NULL)
 300                                 free(t);
 301                         return NULL;
 302                 }
 303
 304                 va_copy(ap_copy, ap);
 305
 306                 ret = vsnprintf(string, size, fmt, ap_copy);
 307                 /* NB! The result of the vsnprintf() might be an *EMPTY* string! */
 308                 if ((ret >= 0) && ((ret + 1) < size))
 309                         break;
 310
 311                 /* there was just enough or not enough space, allocate more in the next round */
 312                 size *= 2; /* double the buffer size */
 313         }
 314
 315         /* the returned buffer is by principle guaranteed to be at least one character longer */
 316         return string;
 317 }
 318
 319 char *alloc_printf(const char *format, ...)
 320 {
 321         char *string;
 322         va_list ap;
 323         va_start(ap, format);
 324         string = alloc_vprintf(format, ap);
 325         va_end(ap);
 326         return string;
 327 }