util/qemu-error.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 error_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 int error_printf_unless_qmp(const char *fmt, ...)
  44 {
  45     va_list ap;
  46     int ret;
  47
  48     va_start(ap, fmt);
  49     ret = error_vprintf_unless_qmp(fmt, ap);
  50     va_end(ap);
  51     return ret;
  52 }
  53
  54 static Location std_loc = {
  55     .kind = LOC_NONE
  56 };
  57 static Location *cur_loc = &std_loc;
  58
  59 /*
  60  * Push location saved in LOC onto the location stack, return it.
  61  * The top of that stack is the current location.
  62  * Needs a matching loc_pop().
  63  */
  64 Location *loc_push_restore(Location *loc)
  65 {
  66     assert(!loc->prev);
  67     loc->prev = cur_loc;
  68     cur_loc = loc;
  69     return loc;
  70 }
  71
  72 /*
  73  * Initialize *LOC to "nowhere", push it onto the location stack.
  74  * The top of that stack is the current location.
  75  * Needs a matching loc_pop().
  76  * Return LOC.
  77  */
  78 Location *loc_push_none(Location *loc)
  79 {
  80     loc->kind = LOC_NONE;
  81     loc->prev = NULL;
  82     return loc_push_restore(loc);
  83 }
  84
  85 /*
  86  * Pop the location stack.
  87  * LOC must be the current location, i.e. the top of the stack.
  88  */
  89 Location *loc_pop(Location *loc)
  90 {
  91     assert(cur_loc == loc && loc->prev);
  92     cur_loc = loc->prev;
  93     loc->prev = NULL;
  94     return loc;
  95 }
  96
  97 /*
  98  * Save the current location in LOC, return LOC.
  99  */
 100 Location *loc_save(Location *loc)
 101 {
 102     *loc = *cur_loc;
 103     loc->prev = NULL;
 104     return loc;
 105 }
 106
 107 /*
 108  * Change the current location to the one saved in LOC.
 109  */
 110 void loc_restore(Location *loc)
 111 {
 112     Location *prev = cur_loc->prev;
 113     assert(!loc->prev);
 114     *cur_loc = *loc;
 115     cur_loc->prev = prev;
 116 }
 117
 118 /*
 119  * Change the current location to "nowhere in particular".
 120  */
 121 void loc_set_none(void)
 122 {
 123     cur_loc->kind = LOC_NONE;
 124 }
 125
 126 /*
 127  * Change the current location to argument ARGV[IDX..IDX+CNT-1].
 128  */
 129 void loc_set_cmdline(char **argv, int idx, int cnt)
 130 {
 131     cur_loc->kind = LOC_CMDLINE;
 132     cur_loc->num = cnt;
 133     cur_loc->ptr = argv + idx;
 134 }
 135
 136 /*
 137  * Change the current location to file FNAME, line LNO.
 138  */
 139 void loc_set_file(const char *fname, int lno)
 140 {
 141     assert (fname || cur_loc->kind == LOC_FILE);
 142     cur_loc->kind = LOC_FILE;
 143     cur_loc->num = lno;
 144     if (fname) {
 145         cur_loc->ptr = fname;
 146     }
 147 }
 148
 149 static const char *progname;
 150
 151 /*
 152  * Set the program name for error_print_loc().
 153  */
 154 static void error_set_progname(const char *argv0)
 155 {
 156     const char *p = strrchr(argv0, '/');
 157     progname = p ? p + 1 : argv0;
 158 }
 159
 160 const char *error_get_progname(void)
 161 {
 162     return progname;
 163 }
 164
 165 /*
 166  * Print current location to current monitor if we have one, else to stderr.
 167  */
 168 static void print_loc(void)
 169 {
 170     const char *sep = "";
 171     int i;
 172     const char *const *argp;
 173
 174     if (!cur_mon && progname) {
 175         fprintf(stderr, "%s:", progname);
 176         sep = " ";
 177     }
 178     switch (cur_loc->kind) {
 179     case LOC_CMDLINE:
 180         argp = cur_loc->ptr;
 181         for (i = 0; i < cur_loc->num; i++) {
 182             error_printf("%s%s", sep, argp[i]);
 183             sep = " ";
 184         }
 185         error_printf(": ");
 186         break;
 187     case LOC_FILE:
 188         error_printf("%s:", (const char *)cur_loc->ptr);
 189         if (cur_loc->num) {
 190             error_printf("%d:", cur_loc->num);
 191         }
 192         error_printf(" ");
 193         break;
 194     default:
 195         error_printf("%s", sep);
 196     }
 197 }
 198
 199 /*
 200  * Print a message to current monitor if we have one, else to stderr.
 201  * @report_type is the type of message: error, warning or informational.
 202  * Format arguments like vsprintf().  The resulting message should be
 203  * a single phrase, with no newline or trailing punctuation.
 204  * Prepend the current location and append a newline.
 205  */
 206 static void vreport(report_type type, const char *fmt, va_list ap)
 207 {
 208     GTimeVal tv;
 209     gchar *timestr;
 210
 211     if (error_with_timestamp && !cur_mon) {
 212         g_get_current_time(&tv);
 213         timestr = g_time_val_to_iso8601(&tv);
 214         error_printf("%s ", timestr);
 215         g_free(timestr);
 216     }
 217
 218     /* Only prepend guest name if -msg guest-name and -name guest=... are set */
 219     if (error_with_guestname && error_guest_name && !cur_mon) {
 220         error_printf("%s ", error_guest_name);
 221     }
 222
 223     print_loc();
 224
 225     switch (type) {
 226     case REPORT_TYPE_ERROR:
 227         break;
 228     case REPORT_TYPE_WARNING:
 229         error_printf("warning: ");
 230         break;
 231     case REPORT_TYPE_INFO:
 232         error_printf("info: ");
 233         break;
 234     }
 235
 236     error_vprintf(fmt, ap);
 237     error_printf("\n");
 238 }
 239
 240 /*
 241  * Print an error message to current monitor if we have one, else to stderr.
 242  * Format arguments like vsprintf().  The resulting message should be
 243  * a single phrase, with no newline or trailing punctuation.
 244  * Prepend the current location and append a newline.
 245  * It's wrong to call this in a QMP monitor.  Use error_setg() there.
 246  */
 247 void error_vreport(const char *fmt, va_list ap)
 248 {
 249     vreport(REPORT_TYPE_ERROR, fmt, ap);
 250 }
 251
 252 /*
 253  * Print a warning message to current monitor if we have one, else to stderr.
 254  * Format arguments like vsprintf().  The resulting message should be
 255  * a single phrase, with no newline or trailing punctuation.
 256  * Prepend the current location and append a newline.
 257  */
 258 void warn_vreport(const char *fmt, va_list ap)
 259 {
 260     vreport(REPORT_TYPE_WARNING, fmt, ap);
 261 }
 262
 263 /*
 264  * Print an information message to current monitor if we have one, else to
 265  * stderr.
 266  * Format arguments like vsprintf().  The resulting message should be
 267  * a single phrase, with no newline or trailing punctuation.
 268  * Prepend the current location and append a newline.
 269  */
 270 void info_vreport(const char *fmt, va_list ap)
 271 {
 272     vreport(REPORT_TYPE_INFO, fmt, ap);
 273 }
 274
 275 /*
 276  * Print an error message to current monitor if we have one, else to stderr.
 277  * Format arguments like sprintf().  The resulting message should be
 278  * a single phrase, with no newline or trailing punctuation.
 279  * Prepend the current location and append a newline.
 280  * It's wrong to call this in a QMP monitor.  Use error_setg() there.
 281  */
 282 void error_report(const char *fmt, ...)
 283 {
 284     va_list ap;
 285
 286     va_start(ap, fmt);
 287     vreport(REPORT_TYPE_ERROR, fmt, ap);
 288     va_end(ap);
 289 }
 290
 291 /*
 292  * Print a warning message to current monitor if we have one, else to stderr.
 293  * Format arguments like sprintf(). The resulting message should be a
 294  * single phrase, with no newline or trailing punctuation.
 295  * Prepend the current location and append a newline.
 296  */
 297 void warn_report(const char *fmt, ...)
 298 {
 299     va_list ap;
 300
 301     va_start(ap, fmt);
 302     vreport(REPORT_TYPE_WARNING, fmt, ap);
 303     va_end(ap);
 304 }
 305
 306 /*
 307  * Print an information message to current monitor if we have one, else to
 308  * stderr.
 309  * Format arguments like sprintf(). The resulting message should be a
 310  * single phrase, with no newline or trailing punctuation.
 311  * Prepend the current location and append a newline.
 312  */
 313 void info_report(const char *fmt, ...)
 314 {
 315     va_list ap;
 316
 317     va_start(ap, fmt);
 318     vreport(REPORT_TYPE_INFO, fmt, ap);
 319     va_end(ap);
 320 }
 321
 322 /*
 323  * Like error_report(), except print just once.
 324  * If *printed is false, print the message, and flip *printed to true.
 325  * Return whether the message was printed.
 326  */
 327 bool error_report_once_cond(bool *printed, const char *fmt, ...)
 328 {
 329     va_list ap;
 330
 331     assert(printed);
 332     if (*printed) {
 333         return false;
 334     }
 335     *printed = true;
 336     va_start(ap, fmt);
 337     vreport(REPORT_TYPE_ERROR, fmt, ap);
 338     va_end(ap);
 339     return true;
 340 }
 341
 342 /*
 343  * Like warn_report(), except print just once.
 344  * If *printed is false, print the message, and flip *printed to true.
 345  * Return whether the message was printed.
 346  */
 347 bool warn_report_once_cond(bool *printed, const char *fmt, ...)
 348 {
 349     va_list ap;
 350
 351     assert(printed);
 352     if (*printed) {
 353         return false;
 354     }
 355     *printed = true;
 356     va_start(ap, fmt);
 357     vreport(REPORT_TYPE_WARNING, fmt, ap);
 358     va_end(ap);
 359     return true;
 360 }
 361
 362 static char *qemu_glog_domains;
 363
 364 static void qemu_log_func(const gchar *log_domain,
 365                           GLogLevelFlags log_level,
 366                           const gchar *message,
 367                           gpointer user_data)
 368 {
 369     switch (log_level & G_LOG_LEVEL_MASK) {
 370     case G_LOG_LEVEL_DEBUG:
 371     case G_LOG_LEVEL_INFO:
 372         /*
 373          * Use same G_MESSAGES_DEBUG logic as glib to enable/disable debug
 374          * messages
 375          */
 376         if (qemu_glog_domains == NULL) {
 377             break;
 378         }
 379         if (strcmp(qemu_glog_domains, "all") != 0 &&
 380           (log_domain == NULL || !strstr(qemu_glog_domains, log_domain))) {
 381             break;
 382         }
 383         /* Fall through */
 384     case G_LOG_LEVEL_MESSAGE:
 385         info_report("%s%s%s",
 386                     log_domain ?: "", log_domain ? ": " : "", message);
 387
 388         break;
 389     case G_LOG_LEVEL_WARNING:
 390         warn_report("%s%s%s",
 391                     log_domain ?: "", log_domain ? ": " : "", message);
 392         break;
 393     case G_LOG_LEVEL_CRITICAL:
 394     case G_LOG_LEVEL_ERROR:
 395         error_report("%s%s%s",
 396                      log_domain ?: "", log_domain ? ": " : "", message);
 397         break;
 398     }
 399 }
 400
 401 void error_init(const char *argv0)
 402 {
 403     /* Set the program name for error_print_loc(). */
 404     error_set_progname(argv0);
 405
 406     /*
 407      * This sets up glib logging so libraries using it also print their logs
 408      * through error_report(), warn_report(), info_report().
 409      */
 410     g_log_set_default_handler(qemu_log_func, NULL);
 411     g_warn_if_fail(qemu_glog_domains == NULL);
 412     qemu_glog_domains = g_strdup(g_getenv("G_MESSAGES_DEBUG"));
 413 }