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 <stdio.h>
  14 #include "monitor.h"
  15
  16 /*
  17  * Print to current monitor if we have one, else to stderr.
  18  * TODO should return int, so callers can calculate width, but that
  19  * requires surgery to monitor_vprintf().  Left for another day.
  20  */
  21 void error_vprintf(const char *fmt, va_list ap)
  22 {
  23     if (cur_mon) {
  24         monitor_vprintf(cur_mon, fmt, ap);
  25     } else {
  26         vfprintf(stderr, fmt, ap);
  27     }
  28 }
  29
  30 /*
  31  * Print to current monitor if we have one, else to stderr.
  32  * TODO just like error_vprintf()
  33  */
  34 void error_printf(const char *fmt, ...)
  35 {
  36     va_list ap;
  37
  38     va_start(ap, fmt);
  39     error_vprintf(fmt, ap);
  40     va_end(ap);
  41 }
  42
  43 void error_printf_unless_qmp(const char *fmt, ...)
  44 {
  45     va_list ap;
  46
  47     if (!monitor_cur_is_qmp()) {
  48         va_start(ap, fmt);
  49         error_vprintf(fmt, ap);
  50         va_end(ap);
  51     }
  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 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 void error_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 an error message to current monitor if we have one, else to stderr.
 201  * Format arguments like sprintf().  The result should not contain
 202  * newlines.
 203  * Prepend the current location and append a newline.
 204  * It's wrong to call this in a QMP monitor.  Use qerror_report() there.
 205  */
 206 void error_report(const char *fmt, ...)
 207 {
 208     va_list ap;
 209
 210     error_print_loc();
 211     va_start(ap, fmt);
 212     error_vprintf(fmt, ap);
 213     va_end(ap);
 214     error_printf("\n");
 215 }