util/log.c

   1 /*
   2  * Logging support
   3  *
   4  *  Copyright (c) 2003 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "qemu-common.h"
  22 #include "qemu/log.h"
  23 #include "qemu/range.h"
  24 #include "qemu/error-report.h"
  25 #include "qapi/error.h"
  26 #include "qemu/cutils.h"
  27 #include "trace/control.h"
  28
  29 static char *logfilename;
  30 FILE *qemu_logfile;
  31 int qemu_loglevel;
  32 static int log_append = 0;
  33 static GArray *debug_regions;
  34
  35 /* Return the number of characters emitted.  */
  36 int qemu_log(const char *fmt, ...)
  37 {
  38     int ret = 0;
  39     if (qemu_logfile) {
  40         va_list ap;
  41         va_start(ap, fmt);
  42         ret = vfprintf(qemu_logfile, fmt, ap);
  43         va_end(ap);
  44
  45         /* Don't pass back error results.  */
  46         if (ret < 0) {
  47             ret = 0;
  48         }
  49     }
  50     return ret;
  51 }
  52
  53 static bool log_uses_own_buffers;
  54
  55 /* enable or disable low levels log */
  56 void qemu_set_log(int log_flags)
  57 {
  58     qemu_loglevel = log_flags;
  59 #ifdef CONFIG_TRACE_LOG
  60     qemu_loglevel |= LOG_TRACE;
  61 #endif
  62     if (!qemu_logfile &&
  63         (is_daemonized() ? logfilename != NULL : qemu_loglevel)) {
  64         if (logfilename) {
  65             qemu_logfile = fopen(logfilename, log_append ? "a" : "w");
  66             if (!qemu_logfile) {
  67                 perror(logfilename);
  68                 _exit(1);
  69             }
  70             /* In case we are a daemon redirect stderr to logfile */
  71             if (is_daemonized()) {
  72                 dup2(fileno(qemu_logfile), STDERR_FILENO);
  73                 fclose(qemu_logfile);
  74                 /* This will skip closing logfile in qemu_log_close() */
  75                 qemu_logfile = stderr;
  76             }
  77         } else {
  78             /* Default to stderr if no log file specified */
  79             assert(!is_daemonized());
  80             qemu_logfile = stderr;
  81         }
  82         /* must avoid mmap() usage of glibc by setting a buffer "by hand" */
  83         if (log_uses_own_buffers) {
  84             static char logfile_buf[4096];
  85
  86             setvbuf(qemu_logfile, logfile_buf, _IOLBF, sizeof(logfile_buf));
  87         } else {
  88 #if defined(_WIN32)
  89             /* Win32 doesn't support line-buffering, so use unbuffered output. */
  90             setvbuf(qemu_logfile, NULL, _IONBF, 0);
  91 #else
  92             setvbuf(qemu_logfile, NULL, _IOLBF, 0);
  93 #endif
  94             log_append = 1;
  95         }
  96     }
  97     if (qemu_logfile &&
  98         (is_daemonized() ? logfilename == NULL : !qemu_loglevel)) {
  99         qemu_log_close();
 100     }
 101 }
 102
 103 void qemu_log_needs_buffers(void)
 104 {
 105     log_uses_own_buffers = true;
 106 }
 107
 108 /*
 109  * Allow the user to include %d in their logfile which will be
 110  * substituted with the current PID. This is useful for debugging many
 111  * nested linux-user tasks but will result in lots of logs.
 112  */
 113 void qemu_set_log_filename(const char *filename, Error **errp)
 114 {
 115     char *pidstr;
 116     g_free(logfilename);
 117
 118     pidstr = strstr(filename, "%");
 119     if (pidstr) {
 120         /* We only accept one %d, no other format strings */
 121         if (pidstr[1] != 'd' || strchr(pidstr + 2, '%')) {
 122             error_setg(errp, "Bad logfile format: %s", filename);
 123             return;
 124         } else {
 125             logfilename = g_strdup_printf(filename, getpid());
 126         }
 127     } else {
 128         logfilename = g_strdup(filename);
 129     }
 130     qemu_log_close();
 131     qemu_set_log(qemu_loglevel);
 132 }
 133
 134 /* Returns true if addr is in our debug filter or no filter defined
 135  */
 136 bool qemu_log_in_addr_range(uint64_t addr)
 137 {
 138     if (debug_regions) {
 139         int i = 0;
 140         for (i = 0; i < debug_regions->len; i++) {
 141             Range *range = &g_array_index(debug_regions, Range, i);
 142             if (range_contains(range, addr)) {
 143                 return true;
 144             }
 145         }
 146         return false;
 147     } else {
 148         return true;
 149     }
 150 }
 151
 152
 153 void qemu_set_dfilter_ranges(const char *filter_spec, Error **errp)
 154 {
 155     gchar **ranges = g_strsplit(filter_spec, ",", 0);
 156     int i;
 157
 158     if (debug_regions) {
 159         g_array_unref(debug_regions);
 160         debug_regions = NULL;
 161     }
 162
 163     debug_regions = g_array_sized_new(FALSE, FALSE,
 164                                       sizeof(Range), g_strv_length(ranges));
 165     for (i = 0; ranges[i]; i++) {
 166         const char *r = ranges[i];
 167         const char *range_op, *r2, *e;
 168         uint64_t r1val, r2val, lob, upb;
 169         struct Range range;
 170
 171         range_op = strstr(r, "-");
 172         r2 = range_op ? range_op + 1 : NULL;
 173         if (!range_op) {
 174             range_op = strstr(r, "+");
 175             r2 = range_op ? range_op + 1 : NULL;
 176         }
 177         if (!range_op) {
 178             range_op = strstr(r, "..");
 179             r2 = range_op ? range_op + 2 : NULL;
 180         }
 181         if (!range_op) {
 182             error_setg(errp, "Bad range specifier");
 183             goto out;
 184         }
 185
 186         if (qemu_strtoull(r, &e, 0, &r1val)
 187             || e != range_op) {
 188             error_setg(errp, "Invalid number to the left of %.*s",
 189                        (int)(r2 - range_op), range_op);
 190             goto out;
 191         }
 192         if (qemu_strtoull(r2, NULL, 0, &r2val)) {
 193             error_setg(errp, "Invalid number to the right of %.*s",
 194                        (int)(r2 - range_op), range_op);
 195             goto out;
 196         }
 197
 198         switch (*range_op) {
 199         case '+':
 200             lob = r1val;
 201             upb = r1val + r2val - 1;
 202             break;
 203         case '-':
 204             upb = r1val;
 205             lob = r1val - (r2val - 1);
 206             break;
 207         case '.':
 208             lob = r1val;
 209             upb = r2val;
 210             break;
 211         default:
 212             g_assert_not_reached();
 213         }
 214         if (lob > upb) {
 215             error_setg(errp, "Invalid range");
 216             goto out;
 217         }
 218         range_set_bounds(&range, lob, upb);
 219         g_array_append_val(debug_regions, range);
 220     }
 221 out:
 222     g_strfreev(ranges);
 223 }
 224
 225 /* fflush() the log file */
 226 void qemu_log_flush(void)
 227 {
 228     fflush(qemu_logfile);
 229 }
 230
 231 /* Close the log file */
 232 void qemu_log_close(void)
 233 {
 234     if (qemu_logfile) {
 235         if (qemu_logfile != stderr) {
 236             fclose(qemu_logfile);
 237         }
 238         qemu_logfile = NULL;
 239     }
 240 }
 241
 242 const QEMULogItem qemu_log_items[] = {
 243     { CPU_LOG_TB_OUT_ASM, "out_asm",
 244       "show generated host assembly code for each compiled TB" },
 245     { CPU_LOG_TB_IN_ASM, "in_asm",
 246       "show target assembly code for each compiled TB" },
 247     { CPU_LOG_TB_OP, "op",
 248       "show micro ops for each compiled TB" },
 249     { CPU_LOG_TB_OP_OPT, "op_opt",
 250       "show micro ops after optimization" },
 251     { CPU_LOG_TB_OP_IND, "op_ind",
 252       "show micro ops before indirect lowering" },
 253     { CPU_LOG_INT, "int",
 254       "show interrupts/exceptions in short format" },
 255     { CPU_LOG_EXEC, "exec",
 256       "show trace before each executed TB (lots of logs)" },
 257     { CPU_LOG_TB_CPU, "cpu",
 258       "show CPU registers before entering a TB (lots of logs)" },
 259     { CPU_LOG_MMU, "mmu",
 260       "log MMU-related activities" },
 261     { CPU_LOG_PCALL, "pcall",
 262       "x86 only: show protected mode far calls/returns/exceptions" },
 263     { CPU_LOG_RESET, "cpu_reset",
 264       "show CPU state before CPU resets" },
 265     { LOG_UNIMP, "unimp",
 266       "log unimplemented functionality" },
 267     { LOG_GUEST_ERROR, "guest_errors",
 268       "log when the guest OS does something invalid (eg accessing a\n"
 269       "non-existent register)" },
 270     { CPU_LOG_PAGE, "page",
 271       "dump pages at beginning of user mode emulation" },
 272     { CPU_LOG_TB_NOCHAIN, "nochain",
 273       "do not chain compiled TBs so that \"exec\" and \"cpu\" show\n"
 274       "complete traces" },
 275     { 0, NULL, NULL },
 276 };
 277
 278 /* takes a comma separated list of log masks. Return 0 if error. */
 279 int qemu_str_to_log_mask(const char *str)
 280 {
 281     const QEMULogItem *item;
 282     int mask = 0;
 283     char **parts = g_strsplit(str, ",", 0);
 284     char **tmp;
 285
 286     for (tmp = parts; tmp && *tmp; tmp++) {
 287         if (g_str_equal(*tmp, "all")) {
 288             for (item = qemu_log_items; item->mask != 0; item++) {
 289                 mask |= item->mask;
 290             }
 291 #ifdef CONFIG_TRACE_LOG
 292         } else if (g_str_has_prefix(*tmp, "trace:") && (*tmp)[6] != '\0') {
 293             trace_enable_events((*tmp) + 6);
 294             mask |= LOG_TRACE;
 295 #endif
 296         } else {
 297             for (item = qemu_log_items; item->mask != 0; item++) {
 298                 if (g_str_equal(*tmp, item->name)) {
 299                     goto found;
 300                 }
 301             }
 302             goto error;
 303         found:
 304             mask |= item->mask;
 305         }
 306     }
 307
 308     g_strfreev(parts);
 309     return mask;
 310
 311  error:
 312     g_strfreev(parts);
 313     return 0;
 314 }
 315
 316 void qemu_print_log_usage(FILE *f)
 317 {
 318     const QEMULogItem *item;
 319     fprintf(f, "Log items (comma separated):\n");
 320     for (item = qemu_log_items; item->mask != 0; item++) {
 321         fprintf(f, "%-15s %s\n", item->name, item->help);
 322     }
 323 #ifdef CONFIG_TRACE_LOG
 324     fprintf(f, "trace:PATTERN   enable trace events\n");
 325     fprintf(f, "\nUse \"-d trace:help\" to get a list of trace events.\n\n");
 326 #endif
 327 }