void LogBuffer::formatStatistics(char **strp, uid_t uid, unsigned int logMask) { log_time oldest(CLOCK_MONOTONIC); pthread_mutex_lock(&mLogElementsLock); // Find oldest element in the log(s) LogBufferElementCollection::iterator it; for (it = mLogElements.begin(); it != mLogElements.end(); ++it) { LogBufferElement *element = *it; if ((logMask & (1 << element->getLogId()))) { oldest = element->getMonotonicTime(); break; } } stats.format(strp, uid, logMask, oldest); pthread_mutex_unlock(&mLogElementsLock); }
// prune "pruneRows" of type "id" from the buffer. // // mLogElementsLock must be held when this function is called. void LogBuffer::prune(log_id_t id, unsigned long pruneRows) { LogTimeEntry *oldest = NULL; LogTimeEntry::lock(); // Region locked? LastLogTimes::iterator t = mTimes.begin(); while(t != mTimes.end()) { LogTimeEntry *entry = (*t); if (entry->owned_Locked() && (!oldest || (oldest->mStart > entry->mStart))) { oldest = entry; } t++; } LogBufferElementCollection::iterator it = mLogElements.begin(); while((pruneRows > 0) && (it != mLogElements.end())) { LogBufferElement *e = *it; if (e->getLogId() == id) { if (oldest && (oldest->mStart <= e->getMonotonicTime())) { if (mSizes[id] > (2 * LOG_BUFFER_SIZE)) { // kick a misbehaving log reader client off the island oldest->release_Locked(); } else { oldest->triggerSkip_Locked(pruneRows); } break; } it = mLogElements.erase(it); mSizes[id] -= e->getMsgLen(); mElements[id]--; delete e; pruneRows--; } else { it++; } } LogTimeEntry::unlock(); }
log_time LogBuffer::flushTo( SocketClient *reader, const log_time start, bool privileged, bool (*filter)(const LogBufferElement *element, void *arg), void *arg) { LogBufferElementCollection::iterator it; log_time max = start; uid_t uid = reader->getUid(); pthread_mutex_lock(&mLogElementsLock); for (it = mLogElements.begin(); it != mLogElements.end(); ++it) { LogBufferElement *element = *it; if (!privileged && (element->getUid() != uid)) { continue; } if (element->getMonotonicTime() <= start) { continue; } // NB: calling out to another object with mLogElementsLock held (safe) if (filter && !(*filter)(element, arg)) { continue; } pthread_mutex_unlock(&mLogElementsLock); // range locking in LastLogTimes looks after us max = element->flushTo(reader); if (max == element->FLUSH_ERROR) { return max; } pthread_mutex_lock(&mLogElementsLock); } pthread_mutex_unlock(&mLogElementsLock); return max; }
// prune "pruneRows" of type "id" from the buffer. // // mLogElementsLock must be held when this function is called. void LogBuffer::prune(log_id_t id, unsigned long pruneRows) { LogTimeEntry *oldest = NULL; LogTimeEntry::lock(); // Region locked? LastLogTimes::iterator t = mTimes.begin(); while(t != mTimes.end()) { LogTimeEntry *entry = (*t); if (entry->owned_Locked() && (!oldest || (oldest->mStart > entry->mStart))) { oldest = entry; } t++; } LogBufferElementCollection::iterator it; // prune by worst offender by uid while (pruneRows > 0) { // recalculate the worst offender on every batched pass uid_t worst = (uid_t) -1; size_t worst_sizes = 0; size_t second_worst_sizes = 0; if ((id != LOG_ID_CRASH) && mPrune.worstUidEnabled()) { LidStatistics &l = stats.id(id); l.sort(); UidStatisticsCollection::iterator iu = l.begin(); if (iu != l.end()) { UidStatistics *u = *iu; worst = u->getUid(); worst_sizes = u->sizes(); if (++iu != l.end()) { second_worst_sizes = (*iu)->sizes(); } } } bool kick = false; for(it = mLogElements.begin(); it != mLogElements.end();) { LogBufferElement *e = *it; if (oldest && (oldest->mStart <= e->getMonotonicTime())) { break; } if (e->getLogId() != id) { ++it; continue; } uid_t uid = e->getUid(); if (uid == worst) { it = mLogElements.erase(it); unsigned short len = e->getMsgLen(); stats.subtract(len, id, worst, e->getPid()); delete e; kick = true; pruneRows--; if ((pruneRows == 0) || (worst_sizes < second_worst_sizes)) { break; } worst_sizes -= len; } else if (mPrune.naughty(e)) { // BlackListed it = mLogElements.erase(it); stats.subtract(e->getMsgLen(), id, uid, e->getPid()); delete e; pruneRows--; if (pruneRows == 0) { break; } } else { ++it; } } if (!kick || !mPrune.worstUidEnabled()) { break; // the following loop will ask bad clients to skip/drop } } bool whitelist = false; it = mLogElements.begin(); while((pruneRows > 0) && (it != mLogElements.end())) { LogBufferElement *e = *it; if (e->getLogId() == id) { if (oldest && (oldest->mStart <= e->getMonotonicTime())) { if (!whitelist) { if (stats.sizes(id) > (2 * log_buffer_size(id))) { // kick a misbehaving log reader client off the island oldest->release_Locked(); } else { oldest->triggerSkip_Locked(pruneRows); } } break; } if (mPrune.nice(e)) { // WhiteListed whitelist = true; it++; continue; } it = mLogElements.erase(it); stats.subtract(e->getMsgLen(), id, e->getUid(), e->getPid()); delete e; pruneRows--; } else { it++; } } if (whitelist && (pruneRows > 0)) { it = mLogElements.begin(); while((it != mLogElements.end()) && (pruneRows > 0)) { LogBufferElement *e = *it; if (e->getLogId() == id) { if (oldest && (oldest->mStart <= e->getMonotonicTime())) { if (stats.sizes(id) > (2 * log_buffer_size(id))) { // kick a misbehaving log reader client off the island oldest->release_Locked(); } else { oldest->triggerSkip_Locked(pruneRows); } break; } it = mLogElements.erase(it); stats.subtract(e->getMsgLen(), id, e->getUid(), e->getPid()); delete e; pruneRows--; } else { it++; } } } LogTimeEntry::unlock(); }