xref: /openbmc/qemu/trace/control.c (revision 7c6da3de)
1 /*
2  * Interface for configuring and controlling the state of tracing events.
3  *
4  * Copyright (C) 2011 Lluís 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 }
43