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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "LogModulePrefWatcher.h"
#include "mozilla/Logging.h"
#include "mozilla/Preferences.h"
#include "mozilla/Services.h"
#include "nsIObserverService.h"
#include "NSPRLogModulesParser.h"
#include "nsString.h"
#include "nsXULAppAPI.h"
#include "prenv.h"
#include "base/process_util.h"
static const char kLoggingPrefPrefix[] = "logging.";
static const char kLoggingConfigPrefPrefix[] = "logging.config";
static const int kLoggingConfigPrefixLen = sizeof(kLoggingConfigPrefPrefix) - 1;
static const char kLoggingPrefClearOnStartup[] =
"logging.config.clear_on_startup";
static const char kLoggingPrefLogFile[] = "logging.config.LOG_FILE";
static const char kLoggingPrefAddTimestamp[] = "logging.config.add_timestamp";
static const char kLoggingPrefSync[] = "logging.config.sync";
static const char kLoggingPrefStacks[] = "logging.config.profilerstacks";
static const char kLoggingPrefLogModules[] = "logging.config.modules";
namespace mozilla {
NS_IMPL_ISUPPORTS(LogModulePrefWatcher, nsIObserver)
/**
* Resets all the preferences in the logging. branch
* This is needed because we may crash while logging, and this would cause us
* to log after restarting as well.
*
* If logging after restart is desired, set the logging.config.clear_on_startup
* pref to false, or use the MOZ_LOG_FILE and MOZ_LOG_MODULES env vars.
*/
static void ResetExistingPrefs() {
nsTArray<nsCString> names;
nsresult rv =
Preferences::GetRootBranch()->GetChildList(kLoggingPrefPrefix, names);
if (NS_SUCCEEDED(rv)) {
for (auto& name : names) {
// Clearing the pref will cause it to reload, thus resetting the log level
Preferences::ClearUser(name.get());
}
}
}
/**
* Loads the log level from the given pref and updates the corresponding
* LogModule.
*/
static void LoadPrefValue(const char* aName) {
LogLevel logLevel = LogLevel::Disabled;
nsresult rv;
int32_t prefLevel = 0;
nsAutoCString prefValue;
if (strncmp(aName, kLoggingConfigPrefPrefix, kLoggingConfigPrefixLen) == 0) {
nsAutoCString prefName(aName);
if (prefName.EqualsLiteral(kLoggingPrefLogFile)) {
rv = Preferences::GetCString(aName, prefValue);
// The pref was reset. Clear the user file.
if (NS_FAILED(rv) || prefValue.IsEmpty()) {
LogModule::SetLogFile(nullptr);
return;
}
// If the pref value doesn't have a PID placeholder, append it to the end.
if (!strstr(prefValue.get(), MOZ_LOG_PID_TOKEN)) {
prefValue.AppendLiteral(MOZ_LOG_PID_TOKEN);
}
LogModule::SetLogFile(prefValue.BeginReading());
} else if (prefName.EqualsLiteral(kLoggingPrefAddTimestamp)) {
bool addTimestamp = Preferences::GetBool(aName, false);
LogModule::SetAddTimestamp(addTimestamp);
} else if (prefName.EqualsLiteral(kLoggingPrefSync)) {
bool sync = Preferences::GetBool(aName, false);
LogModule::SetIsSync(sync);
} else if (prefName.EqualsLiteral(kLoggingPrefStacks)) {
bool captureStacks = Preferences::GetBool(aName, false);
LogModule::SetCaptureStacks(captureStacks);
} else if (prefName.EqualsLiteral(kLoggingPrefLogModules)) {
// The content of the preference will be parsed as a MOZ_LOG string, then
// the corresponding log modules (if any) will be enabled, others will be
// disabled.
LogModule::DisableModules();
LogModule::SetCaptureStacks(false);
const char* modulesFromEnv = PR_GetEnv("MOZ_LOG");
const bool hasModulesEnv = modulesFromEnv && modulesFromEnv[0];
rv = Preferences::GetCString(aName, prefValue);
const bool hasModulesPref = NS_SUCCEEDED(rv) && !prefValue.IsEmpty();
if (hasModulesEnv || hasModulesPref) {
NSPRLogModulesParser(
hasModulesPref ? prefValue.BeginReading() : modulesFromEnv,
[](const char* aName, LogLevel aLevel, int32_t aValue) mutable {
// Only the special string "profilerstacks" is taken into account,
// because we're especially interested in usage with the Firefox
// Profiler.
if (strcmp(aName, "profilerstacks") == 0) {
LogModule::SetCaptureStacks(true);
} else {
LogModule::Get(aName)->SetLevel(aLevel);
}
});
}
}
}
if (Preferences::GetInt(aName, &prefLevel) == NS_OK) {
logLevel = ToLogLevel(prefLevel);
} else if (Preferences::GetCString(aName, prefValue) == NS_OK) {
if (prefValue.LowerCaseEqualsLiteral("error")) {
logLevel = LogLevel::Error;
} else if (prefValue.LowerCaseEqualsLiteral("warning")) {
logLevel = LogLevel::Warning;
} else if (prefValue.LowerCaseEqualsLiteral("info")) {
logLevel = LogLevel::Info;
} else if (prefValue.LowerCaseEqualsLiteral("debug")) {
logLevel = LogLevel::Debug;
} else if (prefValue.LowerCaseEqualsLiteral("verbose")) {
logLevel = LogLevel::Verbose;
}
}
const char* moduleName = aName + strlen(kLoggingPrefPrefix);
LogModule::Get(moduleName)->SetLevel(logLevel);
}
static void LoadExistingPrefs() {
nsIPrefBranch* root = Preferences::GetRootBranch();
if (!root) {
return;
}
nsTArray<nsCString> names;
nsresult rv = root->GetChildList(kLoggingPrefPrefix, names);
if (NS_SUCCEEDED(rv)) {
for (auto& name : names) {
LoadPrefValue(name.get());
}
}
}
LogModulePrefWatcher::LogModulePrefWatcher() = default;
void LogModulePrefWatcher::RegisterPrefWatcher() {
RefPtr<LogModulePrefWatcher> prefWatcher = new LogModulePrefWatcher();
Preferences::AddStrongObserver(prefWatcher, kLoggingPrefPrefix);
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
if (observerService && XRE_IsParentProcess()) {
observerService->AddObserver(prefWatcher,
"browser-delayed-startup-finished", false);
}
LoadExistingPrefs();
}
NS_IMETHODIMP
LogModulePrefWatcher::Observe(nsISupports* aSubject, const char* aTopic,
const char16_t* aData) {
if (strcmp(NS_PREFBRANCH_PREFCHANGE_TOPIC_ID, aTopic) == 0) {
NS_LossyConvertUTF16toASCII prefName(aData);
LoadPrefValue(prefName.get());
} else if (strcmp("browser-delayed-startup-finished", aTopic) == 0) {
bool clear = Preferences::GetBool(kLoggingPrefClearOnStartup, true);
if (clear) {
ResetExistingPrefs();
}
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
if (observerService) {
observerService->RemoveObserver(this, "browser-delayed-startup-finished");
}
}
return NS_OK;
}
} // namespace mozilla