1/*
2 * Copyright 2017 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "tools/trace/EventTracingPriv.h"
9
10#include "include/utils/SkEventTracer.h"
11#include "src/core/SkATrace.h"
12#include "src/core/SkTraceEvent.h"
13#include "tools/flags/CommandLineFlags.h"
14#include "tools/trace/ChromeTracingTracer.h"
15#include "tools/trace/SkDebugfTracer.h"
16
17static DEFINE_string(trace,
18              "",
19              "Log trace events in one of several modes:\n"
20              "  debugf     : Show events using SkDebugf\n"
21              "  atrace     : Send events to Android ATrace\n"
22              "  <filename> : Any other string is interpreted as a filename. Writes\n"
23              "               trace events to specified file as JSON, for viewing\n"
24              "               with chrome://tracing");
25
26static DEFINE_string(traceMatch,
27              "",
28              "Filter which categories are traced.\n"
29              "Uses same format as --match\n");
30
31void initializeEventTracingForTools(const char* traceFlag) {
32    if (!traceFlag) {
33        if (FLAGS_trace.isEmpty()) {
34            return;
35        }
36        traceFlag = FLAGS_trace[0];
37    }
38
39    SkEventTracer* eventTracer = nullptr;
40    if (0 == strcmp(traceFlag, "atrace")) {
41        eventTracer = new SkATrace();
42    } else if (0 == strcmp(traceFlag, "debugf")) {
43        eventTracer = new SkDebugfTracer();
44    } else {
45        eventTracer = new ChromeTracingTracer(traceFlag);
46    }
47
48    SkAssertResult(SkEventTracer::SetInstance(eventTracer));
49}
50
51uint8_t* SkEventTracingCategories::getCategoryGroupEnabled(const char* name) {
52    static_assert(0 == offsetof(CategoryState, fEnabled), "CategoryState");
53
54    // We ignore the "disabled-by-default-" prefix in our internal tools
55    if (SkStrStartsWith(name, TRACE_CATEGORY_PREFIX)) {
56        name += strlen(TRACE_CATEGORY_PREFIX);
57    }
58
59    // Chrome's implementation of this API does a two-phase lookup (once without a lock, then again
60    // with a lock. But the tracing macros avoid calling these functions more than once per site,
61    // so just do something simple (and easier to reason about):
62    SkAutoMutexExclusive lock(fMutex);
63    for (int i = 0; i < fNumCategories; ++i) {
64        if (0 == strcmp(name, fCategories[i].fName)) {
65            return reinterpret_cast<uint8_t*>(&fCategories[i]);
66        }
67    }
68
69    if (fNumCategories >= kMaxCategories) {
70        SkDEBUGFAIL("Exhausted event tracing categories. Increase kMaxCategories.");
71        return reinterpret_cast<uint8_t*>(&fCategories[0]);
72    }
73
74    fCategories[fNumCategories].fEnabled =
75            CommandLineFlags::ShouldSkip(FLAGS_traceMatch, name)
76                    ? 0
77                    : SkEventTracer::kEnabledForRecording_CategoryGroupEnabledFlags;
78
79    fCategories[fNumCategories].fName = name;
80    return reinterpret_cast<uint8_t*>(&fCategories[fNumCategories++]);
81}
82
83const char* SkEventTracingCategories::getCategoryGroupName(const uint8_t* categoryEnabledFlag) {
84    if (categoryEnabledFlag) {
85        return reinterpret_cast<const CategoryState*>(categoryEnabledFlag)->fName;
86    }
87    return nullptr;
88}
89