util/error-report.c

   1 /*
   2  * Error reporting
   3  *
   4  * Copyright (C) 2010 Red Hat Inc.
   5  *
   6  * Authors:
   7  *  Markus Armbruster <armbru@redhat.com>,
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  */
  12
  13 #include "qemu/osdep.h"
  14 #include "monitor/monitor.h"
  15 #include "qemu/error-report.h"
  16
  17 /*
  18  * @report_type is the type of message: error, warning or
  19  * informational.
  20  */
  21 typedef enum {
  22     REPORT_TYPE_ERROR,
  23     REPORT_TYPE_WARNING,
  24     REPORT_TYPE_INFO,
  25 } report_type;
  26
  27 /* Prepend timestamp to messages */
  28 bool message_with_timestamp;
  29 bool error_with_guestname;
  30 const char *error_guest_name;
  31
  32 int error_printf(const char *fmt, ...)
  33 {
  34     va_list ap;
  35     int ret;
  36
  37     va_start(ap, fmt);
  38     ret = error_vprintf(fmt, ap);
  39     va_end(ap);
  40     return ret;
  41 }
  42
  43 static Location std_loc = {
  44     .kind = LOC_NONE
  45 };
  46 static Location *cur_loc = &std_loc;
  47
  48 /*
  49  * Push location saved in LOC onto the location stack, return it.
  50  * The top of that stack is the current location.
  51  * Needs a matching loc_pop().
  52  */
  53 Location *loc_push_restore(Location *loc)
  54 {
  55     assert(!loc->prev);
  56     loc->prev = cur_loc;
  57     cur_loc = loc;
  58     return loc;
  59 }
  60
  61 /*
  62  * Initialize *LOC to "nowhere", push it onto the location stack.
  63  * The top of that stack is the current location.
  64  * Needs a matching loc_pop().
  65  * Return LOC.
  66  */
  67 Location *loc_push_none(Location *loc)
  68 {
  69     loc->kind = LOC_NONE;
  70     loc->prev = NULL;
  71     return loc_push_restore(loc);
  72 }
  73
  74 /*
  75  * Pop the location stack.
  76  * LOC must be the current location, i.e. the top of the stack.
  77  */
  78 Location *loc_pop(Location *loc)
  79 {
  80     assert(cur_loc == loc && loc->prev);
  81     cur_loc = loc->prev;
  82     loc->prev = NULL;
  83     return loc;
  84 }
  85
  86 /*
  87  * Save the current location in LOC, return LOC.
  88  */
  89 Location *loc_save(Location *loc)
  90 {
  91     *loc = *cur_loc;
  92     loc->prev = NULL;
  93     return loc;
  94 }
  95
  96 /*
  97  * Change the current location to the one saved in LOC.
  98  */
  99 void loc_restore(Location *loc)
 100 {
 101     Location *prev = cur_loc->prev;
 102     assert(!loc->prev);
 103     *cur_loc = *loc;
 104     cur_loc->prev = prev;
 105 }
 106
 107 /*
 108  * Change the current location to "nowhere in particular".
 109  */
 110 void loc_set_none(void)
 111 {
 112     cur_loc->kind = LOC_NONE;
 113 }
 114
 115 /*
 116  * Change the current location to argument ARGV[IDX..IDX+CNT-1].
 117  */
 118 void loc_set_cmdline(char **argv, int idx, int cnt)
 119 {
 120     cur_loc->kind = LOC_CMDLINE;
 121     cur_loc->num = cnt;
 122     cur_loc->ptr = argv + idx;
 123 }
 124
 125 /*
 126  * Change the current location to file FNAME, line LNO.
 127  */
 128 void loc_set_file(const char *fname, int lno)
 129 {
 130     assert (fname || cur_loc->kind == LOC_FILE);
 131     cur_loc->kind = LOC_FILE;
 132     cur_loc->num = lno;
 133     if (fname) {
 134         cur_loc->ptr = fname;
 135     }
 136 }
 137
 138 /*
 139  * Print current location to current monitor if we have one, else to stderr.
 140  */
 141 static void print_loc(void)
 142 {
 143     const char *sep = "";
 144     int i;
 145     const char *const *argp;
 146
 147     if (!monitor_cur() && g_get_prgname()) {
 148         error_printf("%s:", g_get_prgname());
 149         sep = " ";
 150     }
 151     switch (cur_loc->kind) {
 152     case LOC_CMDLINE:
 153         argp = cur_loc->ptr;
 154         for (i = 0; i < cur_loc->num; i++) {
 155             error_printf("%s%s", sep, argp[i]);
 156             sep = " ";
 157         }
 158         error_printf(": ");
 159         break;
 160     case LOC_FILE:
 161         error_printf("%s:", (const char *)cur_loc->ptr);
 162         if (cur_loc->num) {
 163             error_printf("%d:", cur_loc->num);
 164         }
 165         error_printf(" ");
 166         break;
 167     default:
 168         error_printf("%s", sep);
 169     }
 170 }
 171
 172 static char *
 173 real_time_iso8601(void)
 174 {
 175     g_autoptr(GDateTime) dt = g_date_time_new_now_utc();
 176     return g_date_time_format_iso8601(dt);
 177 }
 178
 179 /*
 180  * Print a message to current monitor if we have one, else to stderr.
 181  * @report_type is the type of message: error, warning or informational.
 182  * Format arguments like vsprintf().  The resulting message should be
 183  * a single phrase, with no newline or trailing punctuation.
 184  * Prepend the current location and append a newline.
 185  */
 186 G_GNUC_PRINTF(2, 0)
 187 static void vreport(report_type type, const char *fmt, va_list ap)
 188 {
 189     gchar *timestr;
 190
 191     if (message_with_timestamp && !monitor_cur()) {
 192         timestr = real_time_iso8601();
 193         error_printf("%s ", timestr);
 194         g_free(timestr);
 195     }
 196
 197     /* Only prepend guest name if -msg guest-name and -name guest=... are set */
 198     if (error_with_guestname && error_guest_name && !monitor_cur()) {
 199         error_printf("%s ", error_guest_name);
 200     }
 201
 202     print_loc();
 203
 204     switch (type) {
 205     case REPORT_TYPE_ERROR:
 206         break;
 207     case REPORT_TYPE_WARNING:
 208         error_printf("warning: ");
 209         break;
 210     case REPORT_TYPE_INFO:
 211         error_printf("info: ");
 212         break;
 213     }
 214
 215     error_vprintf(fmt, ap);
 216     error_printf("\n");
 217 }
 218
 219 /*
 220  * Print an error message to current monitor if we have one, else to stderr.
 221  * Format arguments like vsprintf().  The resulting message should be
 222  * a single phrase, with no newline or trailing punctuation.
 223  * Prepend the current location and append a newline.
 224  * It's wrong to call this in a QMP monitor.  Use error_setg() there.
 225  */
 226 void error_vreport(const char *fmt, va_list ap)
 227 {
 228     vreport(REPORT_TYPE_ERROR, fmt, ap);
 229 }
 230
 231 /*
 232  * Print a warning message to current monitor if we have one, else to stderr.
 233  * Format arguments like vsprintf().  The resulting message should be
 234  * a single phrase, with no newline or trailing punctuation.
 235  * Prepend the current location and append a newline.
 236  */
 237 void warn_vreport(const char *fmt, va_list ap)
 238 {
 239     vreport(REPORT_TYPE_WARNING, fmt, ap);
 240 }
 241
 242 /*
 243  * Print an information message to current monitor if we have one, else to
 244  * stderr.
 245  * Format arguments like vsprintf().  The resulting message should be
 246  * a single phrase, with no newline or trailing punctuation.
 247  * Prepend the current location and append a newline.
 248  */
 249 void info_vreport(const char *fmt, va_list ap)
 250 {
 251     vreport(REPORT_TYPE_INFO, fmt, ap);
 252 }
 253
 254 /*
 255  * Print an error message to current monitor if we have one, else to stderr.
 256  * Format arguments like sprintf().  The resulting message should be
 257  * a single phrase, with no newline or trailing punctuation.
 258  * Prepend the current location and append a newline.
 259  * It's wrong to call this in a QMP monitor.  Use error_setg() there.
 260  */
 261 void error_report(const char *fmt, ...)
 262 {
 263     va_list ap;
 264
 265     va_start(ap, fmt);
 266     vreport(REPORT_TYPE_ERROR, fmt, ap);
 267     va_end(ap);
 268 }
 269
 270 /*
 271  * Print a warning message to current monitor if we have one, else to stderr.
 272  * Format arguments like sprintf(). The resulting message should be a
 273  * single phrase, with no newline or trailing punctuation.
 274  * Prepend the current location and append a newline.
 275  */
 276 void warn_report(const char *fmt, ...)
 277 {
 278     va_list ap;
 279
 280     va_start(ap, fmt);
 281     vreport(REPORT_TYPE_WARNING, fmt, ap);
 282     va_end(ap);
 283 }
 284
 285 /*
 286  * Print an information message to current monitor if we have one, else to
 287  * stderr.
 288  * Format arguments like sprintf(). The resulting message should be a
 289  * single phrase, with no newline or trailing punctuation.
 290  * Prepend the current location and append a newline.
 291  */
 292 void info_report(const char *fmt, ...)
 293 {
 294     va_list ap;
 295
 296     va_start(ap, fmt);
 297     vreport(REPORT_TYPE_INFO, fmt, ap);
 298     va_end(ap);
 299 }
 300
 301 /*
 302  * Like error_report(), except print just once.
 303  * If *printed is false, print the message, and flip *printed to true.
 304  * Return whether the message was printed.
 305  */
 306 bool error_report_once_cond(bool *printed, const char *fmt, ...)
 307 {
 308     va_list ap;
 309
 310     assert(printed);
 311     if (*printed) {
 312         return false;
 313     }
 314     *printed = true;
 315     va_start(ap, fmt);
 316     vreport(REPORT_TYPE_ERROR, fmt, ap);
 317     va_end(ap);
 318     return true;
 319 }
 320
 321 /*
 322  * Like warn_report(), except print just once.
 323  * If *printed is false, print the message, and flip *printed to true.
 324  * Return whether the message was printed.
 325  */
 326 bool warn_report_once_cond(bool *printed, const char *fmt, ...)
 327 {
 328     va_list ap;
 329
 330     assert(printed);
 331     if (*printed) {
 332         return false;
 333     }
 334     *printed = true;
 335     va_start(ap, fmt);
 336     vreport(REPORT_TYPE_WARNING, fmt, ap);
 337     va_end(ap);
 338     return true;
 339 }
 340
 341 static char *qemu_glog_domains;
 342
 343 static void qemu_log_func(const gchar *log_domain,
 344                           GLogLevelFlags log_level,
 345                           const gchar *message,
 346                           gpointer user_data)
 347 {
 348     switch (log_level & G_LOG_LEVEL_MASK) {
 349     case G_LOG_LEVEL_DEBUG:
 350     case G_LOG_LEVEL_INFO:
 351         /*
 352          * Use same G_MESSAGES_DEBUG logic as glib to enable/disable debug
 353          * messages
 354          */
 355         if (qemu_glog_domains == NULL) {
 356             break;
 357         }
 358         if (strcmp(qemu_glog_domains, "all") != 0 &&
 359           (log_domain == NULL || !strstr(qemu_glog_domains, log_domain))) {
 360             break;
 361         }
 362         /* Fall through */
 363     case G_LOG_LEVEL_MESSAGE:
 364         info_report("%s%s%s",
 365                     log_domain ?: "", log_domain ? ": " : "", message);
 366
 367         break;
 368     case G_LOG_LEVEL_WARNING:
 369         warn_report("%s%s%s",
 370                     log_domain ?: "", log_domain ? ": " : "", message);
 371         break;
 372     case G_LOG_LEVEL_CRITICAL:
 373     case G_LOG_LEVEL_ERROR:
 374         error_report("%s%s%s",
 375                      log_domain ?: "", log_domain ? ": " : "", message);
 376         break;
 377     }
 378 }
 379
 380 void error_init(const char *argv0)
 381 {
 382     const char *p = strrchr(argv0, '/');
 383
 384     /* Set the program name for error_print_loc(). */
 385     g_set_prgname(p ? p + 1 : argv0);
 386
 387     /*
 388      * This sets up glib logging so libraries using it also print their logs
 389      * through error_report(), warn_report(), info_report().
 390      */
 391     g_log_set_default_handler(qemu_log_func, NULL);
 392     g_warn_if_fail(qemu_glog_domains == NULL);
 393     qemu_glog_domains = g_strdup(g_getenv("G_MESSAGES_DEBUG"));
 394 }