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
  33 #define PRINT_MEM() 0
  34 #if PRINT_MEM()
  35 #include <malloc.h>
  36 #endif
  37
  38 int debug_level = -1;
  39
  40 static FILE* log_output;
  41 static log_callback_t *log_callbacks = NULL;
  42
  43 static long long start;
  44
  45 static char *log_strings[5] =
  46 {
  47         "User:   ",
  48         "Error:  ",
  49         "Warning:",
  50         "Info:   ",
  51         "Debug:  "
  52 };
  53
  54 static int count = 0;
  55
  56 /* The log_puts() serves to somewhat different goals:
  57  *
  58  * - logging
  59  * - feeding low-level info to the user in GDB or Telnet
  60  *
  61  * The latter dictates that strings without newline are not logged, lest there
  62  * will be *MANY log lines when sending one char at the time(e.g.
  63  * target_request.c).
  64  *
  65  */
  66 static void log_puts(enum log_levels level, const char *file, int line, const char *function, const char *string)
  67 {
  68         char *f;
  69         if (level == LOG_LVL_OUTPUT)
  70         {
  71                 /* do not prepend any headers, just print out what we were given and return */
  72                 fputs(string, log_output);
  73                 fflush(log_output);
  74                 return;
  75         }
  76
  77         f = strrchr(file, '/');
  78         if (f != NULL)
  79                 file = f + 1;
  80
  81         if (strchr(string, '\n')!=NULL)
  82         {
  83                 if (debug_level >= LOG_LVL_DEBUG)
  84                 {
  85                         /* print with count and time information */
  86                         int t=(int)(timeval_ms()-start);
  87 #if PRINT_MEM()
  88                         struct mallinfo info;
  89                         info = mallinfo();
  90 #endif
  91                         fprintf(log_output, "%s %d %d %s:%d %s()"
  92 #if PRINT_MEM()
  93                                         " %d"
  94 #endif
  95                                         ": %s", log_strings[level+1], count, t, file, line, function,
  96 #if PRINT_MEM()
  97                                         info.fordblks,
  98 #endif
  99                                         string);
 100                 }
 101                 else
 102                 {
 103                         /* do not print count and time */
 104                         fprintf(log_output, "%s %s:%d %s(): %s", log_strings[level+1], file, line, function, string);
 105                 }
 106         } else
 107         {
 108                 /* only entire lines are logged. Otherwise it's
 109                  * single chars intended for the log callbacks. */
 110         }
 111
 112         fflush(log_output);
 113
 114         /* Never forward LOG_LVL_DEBUG, too verbose and they can be found in the log if need be */
 115         if (level <= LOG_LVL_INFO)
 116         {
 117                 log_callback_t *cb, *next;
 118                 cb = log_callbacks;
 119                 /* DANGER!!!! the log callback can remove itself!!!! */
 120                 while (cb)
 121                 {
 122                         next=cb->next;
 123                         cb->fn(cb->priv, file, line, function, string);
 124                         cb=next;
 125                 }
 126         }
 127 }
 128
 129 void log_printf(enum log_levels level, const char *file, int line, const char *function, const char *format, ...)
 130 {
 131         char *string;
 132         va_list ap;
 133
 134         count++;
 135         if (level > debug_level)
 136                 return;
 137
 138         va_start(ap, format);
 139
 140         string = alloc_vprintf(format, ap);
 141         if (string != NULL)
 142         {
 143                 log_puts(level, file, line, function, string);
 144                 free(string);
 145         }
 146
 147         va_end(ap);
 148 }
 149
 150 void log_printf_lf(enum log_levels level, const char *file, int line, const char *function, const char *format, ...)
 151 {
 152         char *string;
 153         va_list ap;
 154
 155         count++;
 156         if (level > debug_level)
 157                 return;
 158
 159         va_start(ap, format);
 160
 161         string = alloc_vprintf(format, ap);
 162         if (string != NULL)
 163         {
 164                 strcat(string, "\n"); /* alloc_vprintf guaranteed the buffer to be at least one char longer */
 165                 log_puts(level, file, line, function, string);
 166                 free(string);
 167         }
 168
 169         va_end(ap);
 170 }
 171
 172 /* change the current debug level on the fly
 173  * 0: only ERRORS
 174  * 1: + WARNINGS
 175  * 2: + INFORMATIONAL MSGS
 176  * 3: + DEBUG MSGS
 177  */
 178 int handle_debug_level_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 179 {
 180         if (argc == 0)
 181                 command_print(cmd_ctx, "debug_level: %i", debug_level);
 182
 183         if (argc > 0)
 184                 debug_level = strtoul(args[0], NULL, 0);
 185
 186         if (debug_level < 0)
 187                 debug_level = 0;
 188
 189         if (debug_level > 3)
 190                 debug_level = 3;
 191
 192         return ERROR_OK;
 193 }
 194
 195 int handle_log_output_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 196 {
 197         if (argc == 1)
 198         {
 199                 FILE* file = fopen(args[0], "w");
 200
 201                 if (file)
 202                 {
 203                         log_output = file;
 204                 }
 205         }
 206
 207         return ERROR_OK;
 208 }
 209
 210 int log_register_commands(struct command_context_s *cmd_ctx)
 211 {
 212         start = timeval_ms();
 213         register_command(cmd_ctx, NULL, "log_output", handle_log_output_command,
 214                 COMMAND_ANY, "redirect logging to <file> (default: stderr)");
 215         register_command(cmd_ctx, NULL, "debug_level", handle_debug_level_command,
 216                 COMMAND_ANY, "adjust debug level <0-3>");
 217
 218         return ERROR_OK;
 219 }
 220
 221 int log_init(struct command_context_s *cmd_ctx)
 222 {
 223         /* set defaults for daemon configuration, if not set by cmdline or cfgfile */
 224         if (debug_level == -1)
 225                 debug_level = LOG_LVL_INFO;
 226
 227         if (log_output == NULL)
 228         {
 229                 log_output = stderr;
 230         }
 231
 232         return ERROR_OK;
 233 }
 234
 235 int set_log_output(struct command_context_s *cmd_ctx, FILE *output)
 236 {
 237         log_output = output;
 238         return ERROR_OK;
 239 }
 240
 241 /* add/remove log callback handler */
 242 int log_add_callback(log_callback_fn fn, void *priv)
 243 {
 244         log_callback_t *cb;
 245
 246         /* prevent the same callback to be registered more than once, just for sure */
 247         for (cb = log_callbacks; cb; cb = cb->next)
 248         {
 249                 if (cb->fn == fn && cb->priv == priv)
 250                         return ERROR_INVALID_ARGUMENTS;
 251         }
 252
 253         /* alloc memory, it is safe just to return in case of an error, no need for the caller to check this */
 254         if ((cb = malloc(sizeof(log_callback_t))) == NULL)
 255                 return ERROR_BUF_TOO_SMALL;
 256
 257         /* add item to the beginning of the linked list */
 258         cb->fn = fn;
 259         cb->priv = priv;
 260         cb->next = log_callbacks;
 261         log_callbacks = cb;
 262
 263         return ERROR_OK;
 264 }
 265
 266 int log_remove_callback(log_callback_fn fn, void *priv)
 267 {
 268         log_callback_t *cb, **p;
 269
 270         for (p = &log_callbacks; (cb = *p); p = &(*p)->next)
 271         {
 272                 if (cb->fn == fn && cb->priv == priv)
 273                 {
 274                         *p = cb->next;
 275                         free(cb);
 276                         return ERROR_OK;
 277                 }
 278         }
 279
 280         /* no such item */
 281         return ERROR_INVALID_ARGUMENTS;
 282 }
 283
 284 /* return allocated string w/printf() result */
 285 char *alloc_vprintf(const char *fmt, va_list ap)
 286 {
 287         /* no buffer at the beginning, force realloc to do the job */
 288         char *string = NULL;
 289
 290         /* start with buffer size suitable for typical messages */
 291         int size = 128;
 292
 293         for (;;)
 294         {
 295                 char *t = string;
 296                 va_list ap_copy;
 297                 int ret;
 298                 string = realloc(string, size);
 299                 if (string == NULL)
 300                 {
 301                         if (t != NULL)
 302                                 free(t);
 303                         return NULL;
 304                 }
 305
 306                 va_copy(ap_copy, ap);
 307
 308                 ret = vsnprintf(string, size, fmt, ap_copy);
 309                 /* NB! The result of the vsnprintf() might be an *EMPTY* string! */
 310                 if ((ret >= 0) && ((ret + 1) < size))
 311                         break;
 312
 313                 /* there was just enough or not enough space, allocate more in the next round */
 314                 size *= 2; /* double the buffer size */
 315         }
 316
 317         /* the returned buffer is by principle guaranteed to be at least one character longer */
 318         return string;
 319 }
 320
 321 char *alloc_printf(const char *format, ...)
 322 {
 323         char *string;
 324         va_list ap;
 325         va_start(ap, format);
 326         string = alloc_vprintf(format, ap);
 327         va_end(ap);
 328         return string;
 329 }