Move crash keys for command-line switches to components/crash so they can be set

components/crash/core/common/crash_keys.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_CRASH_CORE_COMMON_CRASH_KEYS_H_
 #define COMPONENTS_CRASH_CORE_COMMON_CRASH_KEYS_H_
 
 #include <string>
 #include <vector>
 
+#include "base/callback_forward.h"
+#include "base/debug/crash_logging.h"
 #include "build/build_config.h"
 
+namespace base {
+class CommandLine;
+}  // namespace base
+
 namespace crash_keys {
 
 // Sets the ID (which may either be a full GUID or a GUID that was already
 // stripped from its dashes -- in either case this method will strip remaining
 // dashes before setting the crash key).
 void SetMetricsClientIdFromGUID(const std::string& metrics_client_guid);
 void ClearMetricsClientId();
 
 // Sets the list of active experiment/variations info.
 void SetVariationsList(const std::vector<std::string>& variations);
 
+// Adds a common set of crash keys for holding command-line switches to |keys|.
+void GetCrashKeysForCommandLineSwitches(
+    std::vector<base::debug::CrashKey>* keys);
+
+// Sets the kSwitch and kNumSwitches keys based on the given |command_line|.
+void SetSwitchesFromCommandLine(const base::CommandLine& command_line);

[grt (UTC plus 2), 2015/11/27 18:51:21]

rather than overloading the function, i think it's better to have callers pass
in either an empty callback or a null function pointer (my preference).

[Joe Mason, 2015/11/27 21:16:47]

Done.

+
+// Sets the kSwitch and kNumSwitches keys based on the given |command_line|.
+// Ignore any switch for which |skip_filter| returns true.
+void SetSwitchesFromCommandLine(const base::CommandLine& command_line,
+    const base::Callback<bool(const std::string &)>& skip_filter);

[grt (UTC plus 2), 2015/11/27 18:51:21]

callback seems like overkill. how about starting with a simple function pointer
for now? this can be expanded to a callback in the future if needed.

[Joe Mason, 2015/11/27 21:16:47]

Done.

+
 // Crash Key Constants /////////////////////////////////////////////////////////
 
 // kChunkMaxLength is the platform-specific maximum size that a value in a
 // single chunk can be; see base::debug::InitCrashKeys. The maximum lengths
 // specified by breakpad include the trailing NULL, so the actual length of the
 // chunk is one less.
 #if defined(OS_MACOSX)
 const size_t kChunkMaxLength = 255;
 #else  // OS_MACOSX
 const size_t kChunkMaxLength = 63;
@@ skipping 27 matching lines @@
 // The product release/distribution channel.
 extern const char kChannel[];
 
 // The total number of experiments the instance has.
 extern const char kNumVariations[];
 
 // The experiments chunk. Hashed experiment names separated by |,|. This is
 // typically set by SetExperimentList.
 extern const char kVariations[];
 
+// Process command line switches. |kSwitch| should be formatted with an integer,
+// in the range [1, kSwitchesMaxCount].
+const size_t kSwitchesMaxCount = 15;
+extern const char kSwitch[];

[grt (UTC plus 2), 2015/11/27 18:51:21]

may as well document this for what it is:
// A printf-style format string naming the set of crash keys corresponding to at
most |kSwitchesMaxCount| command line switches.

i wouldn't object to you renaming this to kSwitchFormat or something like that
since it's a format string rather than an actual crash key name.

[Joe Mason, 2015/11/27 21:16:47]

Done.

+// The total number of switches, used to report the total in case more than

[grt (UTC plus 2), 2015/11/27 18:51:21]

nit: blank line before comment

[Joe Mason, 2015/11/27 21:16:47]

Done.

+// |kSwitchesMaxCount| are present.
+extern const char kNumSwitches[];
+
 // Used to help investigate bug 464926.
 extern const char kBug464926CrashKey[];
 
 #if defined(OS_MACOSX)
 namespace mac {
 
 // Records Cocoa zombie/used-after-freed objects that resulted in a
 // deliberate crash.
 extern const char kZombie[];
 extern const char kZombieTrace[];
 
 }  // namespace mac
 #endif
 
 }  // namespace crash_keys
 
 #endif  // COMPONENTS_CRASH_CORE_COMMON_CRASH_KEYS_H_