michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 et sw=2 tw=80: */
michael@0: 
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /* Original author: bcampen@mozilla.com */
michael@0: 
michael@0: #include <cstdarg>
michael@0: 
michael@0: #include "rlogringbuffer.h"
michael@0: 
michael@0: #include <deque>
michael@0: #include <string>
michael@0: #include "mozilla/Assertions.h"
michael@0: #include "mozilla/Move.h" // Pinch hitting for <utility> and std::move
michael@0: #include "mozilla/Mutex.h"
michael@0: #include "mozilla/NullPtr.h"
michael@0: #include <vector>
michael@0: 
michael@0: extern "C" {
michael@0: #include <csi_platform.h>
michael@0: #include "r_log.h"
michael@0: }
michael@0: 
michael@0: /* Matches r_dest_vlog type defined in r_log.h */
michael@0: static int ringbuffer_vlog(int facility,
michael@0:                            int level,
michael@0:                            const char *format,
michael@0:                            va_list ap) {
michael@0:   MOZ_ASSERT(mozilla::RLogRingBuffer::GetInstance());
michael@0:   // I could be evil and printf right into a std::string, but unless this
michael@0:   // shows up in profiling, it is not worth doing.
michael@0:   char temp[4096];
michael@0:   vsnprintf(temp, sizeof(temp), format, ap);
michael@0: 
michael@0:   mozilla::RLogRingBuffer::GetInstance()->Log(std::string(temp));
michael@0:   return 0;
michael@0: }
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: RLogRingBuffer* RLogRingBuffer::instance;
michael@0: 
michael@0: RLogRingBuffer::RLogRingBuffer()
michael@0:   : log_limit_(4096),
michael@0:     mutex_("RLogRingBuffer::mutex_") {
michael@0: }
michael@0: 
michael@0: RLogRingBuffer::~RLogRingBuffer() {
michael@0: }
michael@0: 
michael@0: void RLogRingBuffer::SetLogLimit(uint32_t new_limit) {
michael@0:   OffTheBooksMutexAutoLock lock(mutex_);
michael@0:   log_limit_ = new_limit;
michael@0:   RemoveOld();
michael@0: }
michael@0: 
michael@0: void RLogRingBuffer::Log(std::string&& log) {
michael@0:   OffTheBooksMutexAutoLock lock(mutex_);
michael@0:   log_messages_.push_front(Move(log));
michael@0:   RemoveOld();
michael@0: }
michael@0: 
michael@0: inline void RLogRingBuffer::RemoveOld() {
michael@0:   if (log_messages_.size() > log_limit_) {
michael@0:     log_messages_.resize(log_limit_);
michael@0:   }
michael@0: }
michael@0: 
michael@0: 
michael@0: RLogRingBuffer* RLogRingBuffer::CreateInstance() {
michael@0:   if (!instance) {
michael@0:     instance = new RLogRingBuffer;
michael@0:     r_log_set_extra_destination(LOG_INFO, &ringbuffer_vlog);
michael@0:   }
michael@0:   return instance;
michael@0: }
michael@0: 
michael@0: RLogRingBuffer* RLogRingBuffer::GetInstance() {
michael@0:   return instance;
michael@0: }
michael@0: 
michael@0: void RLogRingBuffer::DestroyInstance() {
michael@0:   // First param is ignored when passing null
michael@0:   r_log_set_extra_destination(LOG_INFO, nullptr);
michael@0:   delete instance;
michael@0:   instance = nullptr;
michael@0: }
michael@0: 
michael@0: void RLogRingBuffer::Filter(const std::string& substring,
michael@0:                             uint32_t limit,
michael@0:                             std::deque<std::string>* matching_logs) {
michael@0:   std::vector<std::string> substrings;
michael@0:   substrings.push_back(substring);
michael@0:   FilterAny(substrings, limit, matching_logs);
michael@0: }
michael@0: 
michael@0: inline bool AnySubstringMatches(const std::vector<std::string>& substrings,
michael@0:                                 const std::string& string) {
michael@0:   for (auto sub = substrings.begin(); sub != substrings.end(); ++sub) {
michael@0:     if (string.find(*sub) != std::string::npos) {
michael@0:       return true;
michael@0:     }
michael@0:   }
michael@0:   return false;
michael@0: }
michael@0: 
michael@0: void RLogRingBuffer::FilterAny(const std::vector<std::string>& substrings,
michael@0:                                uint32_t limit,
michael@0:                                std::deque<std::string>* matching_logs) {
michael@0:   OffTheBooksMutexAutoLock lock(mutex_);
michael@0:   if (limit == 0) {
michael@0:     // At a max, all of the log messages.
michael@0:     limit = log_limit_;
michael@0:   }
michael@0: 
michael@0:   for (auto log = log_messages_.begin();
michael@0:        log != log_messages_.end() && matching_logs->size() < limit;
michael@0:        ++log) {
michael@0:     if (AnySubstringMatches(substrings, *log)) {
michael@0:       matching_logs->push_front(*log);
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: } // namespace mozilla
michael@0: