linux-user: save auxv length
[qemu.git] / trace / control.c
1 /*
2 * Interface for configuring and controlling the state of tracing events.
3 *
4 * Copyright (C) 2011 LluĂ­s Vilanova <vilanova@ac.upc.edu>
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2. See
7 * the COPYING file in the top-level directory.
8 */
9
10 #include "trace/control.h"
11
12
13 void trace_backend_init_events(const char *fname)
14 {
15 if (fname == NULL) {
16 return;
17 }
18
19 FILE *fp = fopen(fname, "r");
20 if (!fp) {
21 fprintf(stderr, "error: could not open trace events file '%s': %s\n",
22 fname, strerror(errno));
23 exit(1);
24 }
25 char line_buf[1024];
26 while (fgets(line_buf, sizeof(line_buf), fp)) {
27 size_t len = strlen(line_buf);
28 if (len > 1) { /* skip empty lines */
29 line_buf[len - 1] = '\0';
30 if (!trace_event_set_state(line_buf, true)) {
31 fprintf(stderr,
32 "error: trace event '%s' does not exist\n", line_buf);
33 exit(1);
34 }
35 }
36 }
37 if (fclose(fp) != 0) {
38 fprintf(stderr, "error: closing file '%s': %s\n",
39 fname, strerror(errno));
40 exit(1);
41 }
42 }