示例#1
0
// A second pass to send the selected elements
int LogTimeEntry::FilterSecondPass(const LogBufferElement *element, void *obj) {
    LogTimeEntry *me = reinterpret_cast<LogTimeEntry *>(obj);

    LogTimeEntry::lock();

    me->mStart = element->getSequence();

    if (me->skipAhead[element->getLogId()]) {
        me->skipAhead[element->getLogId()]--;
        goto skip;
    }

    // Truncate to close race between first and second pass
    if (me->mNonBlock && me->mTail && (me->mIndex >= me->mCount)) {
        goto stop;
    }

    if (!me->isWatching(element->getLogId())) {
        goto skip;
    }

    if (me->mPid && (me->mPid != element->getPid())) {
        goto skip;
    }

    if (me->isError_Locked()) {
        goto stop;
    }

    if (!me->mTail) {
        goto ok;
    }

    ++me->mIndex;

    if ((me->mCount > me->mTail) && (me->mIndex <= (me->mCount - me->mTail))) {
        goto skip;
    }

    if (!me->mNonBlock) {
        me->mTail = 0;
    }

ok:
    if (!me->skipAhead[element->getLogId()]) {
        LogTimeEntry::unlock();
        return true;
    }
    // FALLTHRU

skip:
    LogTimeEntry::unlock();
    return false;

stop:
    LogTimeEntry::unlock();
    return -1;
}
void *LogTimeEntry::threadStart(void *obj) {
    prctl(PR_SET_NAME, "logd.reader.per");

    LogTimeEntry *me = reinterpret_cast<LogTimeEntry *>(obj);

    pthread_cleanup_push(threadStop, obj);

    SocketClient *client = me->mClient;
    if (!client) {
        me->error();
        pthread_exit(NULL);
    }

    LogBuffer &logbuf = me->mReader.logbuf();

    bool privileged = FlushCommand::hasReadLogs(client);

    lock();

    me->threadTriggered = true;

    while(me->threadTriggered && !me->isError_Locked()) {

        me->threadTriggered = false;

        log_time start = me->mStart;

        unlock();

        if (me->mTail) {
            logbuf.flushTo(client, start, privileged, FilterFirstPass, me);
        }
        start = logbuf.flushTo(client, start, privileged, FilterSecondPass, me);

        if (start == LogBufferElement::FLUSH_ERROR) {
            me->error();
        }

        if (me->mNonBlock) {
            lock();
            break;
        }

        sched_yield();

        lock();
    }

    unlock();

    pthread_exit(NULL);

    pthread_cleanup_pop(true);

    return NULL;
}
// A second pass to send the selected elements
bool LogTimeEntry::FilterSecondPass(const LogBufferElement *element, void *obj) {
    LogTimeEntry *me = reinterpret_cast<LogTimeEntry *>(obj);

    LogTimeEntry::lock();

    if (me->skipAhead) {
        me->skipAhead--;
    }

    me->mStart = element->getMonotonicTime();

    // Truncate to close race between first and second pass
    if (me->mNonBlock && me->mTail && (me->mIndex >= me->mCount)) {
        goto skip;
    }

    if ((me->mLogMask & (1 << element->getLogId())) == 0) {
        goto skip;
    }

    if (me->mPid && (me->mPid != element->getPid())) {
        goto skip;
    }

    if (me->isError_Locked()) {
        goto skip;
    }

    if (!me->mTail) {
        goto ok;
    }

    ++me->mIndex;

    if ((me->mCount > me->mTail) && (me->mIndex <= (me->mCount - me->mTail))) {
        goto skip;
    }

    if (!me->mNonBlock) {
        me->mTail = 0;
    }

ok:
    if (!me->skipAhead) {
        LogTimeEntry::unlock();
        return true;
    }
    // FALLTHRU

skip:
    LogTimeEntry::unlock();
    return false;
}
void LogReader::doSocketDelete(SocketClient *cli) {
    LastLogTimes &times = mLogbuf.mTimes;
    LogTimeEntry::lock();
    LastLogTimes::iterator it = times.begin();
    while(it != times.end()) {
        LogTimeEntry *entry = (*it);
        if (entry->mClient == cli) {
            times.erase(it);
            entry->release_Locked();
            break;
        }
        it++;
    }
    LogTimeEntry::unlock();
}
示例#5
0
// A first pass to count the number of elements
int LogTimeEntry::FilterFirstPass(const LogBufferElement *element, void *obj) {
    LogTimeEntry *me = reinterpret_cast<LogTimeEntry *>(obj);

    LogTimeEntry::lock();

    if (me->mCount == 0) {
        me->mStart = element->getSequence();
    }

    if ((!me->mPid || (me->mPid == element->getPid()))
            && (me->isWatching(element->getLogId()))) {
        ++me->mCount;
    }

    LogTimeEntry::unlock();

    return false;
}
// 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();
}
示例#7
0
// clear all rows of type "id" from the buffer.
bool LogBuffer::clear(log_id_t id, uid_t uid) {
    bool busy = true;
    // If it takes more than 4 tries (seconds) to clear, then kill reader(s)
    for (int retry = 4;;) {
        if (retry == 1) { // last pass
            // Check if it is still busy after the sleep, we say prune
            // one entry, not another clear run, so we are looking for
            // the quick side effect of the return value to tell us if
            // we have a _blocked_ reader.
            pthread_mutex_lock(&mLogElementsLock);
            busy = prune(id, 1, uid);
            pthread_mutex_unlock(&mLogElementsLock);
            // It is still busy, blocked reader(s), lets kill them all!
            // otherwise, lets be a good citizen and preserve the slow
            // readers and let the clear run (below) deal with determining
            // if we are still blocked and return an error code to caller.
            if (busy) {
                LogTimeEntry::lock();
                LastLogTimes::iterator times = mTimes.begin();
                while (times != mTimes.end()) {
                    LogTimeEntry *entry = (*times);
                    // Killer punch
                    if (entry->owned_Locked() && entry->isWatching(id)) {
                        entry->release_Locked();
                    }
                    times++;
                }
                LogTimeEntry::unlock();
            }
        }
        pthread_mutex_lock(&mLogElementsLock);
        busy = prune(id, ULONG_MAX, uid);
        pthread_mutex_unlock(&mLogElementsLock);
        if (!busy || !--retry) {
            break;
        }
        sleep (1); // Let reader(s) catch up after notification
    }
    return busy;
}
示例#8
0
void LogTimeEntry::threadStop(void *obj) {
    LogTimeEntry *me = reinterpret_cast<LogTimeEntry *>(obj);

    lock();

    if (me->mNonBlock) {
        me->error_Locked();
    }

    SocketClient *client = me->mClient;

    if (me->isError_Locked()) {
        LogReader &reader = me->mReader;
        LastLogTimes &times = reader.logbuf().mTimes;

        LastLogTimes::iterator it = times.begin();
        while(it != times.end()) {
            if (*it == me) {
                times.erase(it);
                me->release_Locked();
                break;
            }
            it++;
        }

        me->mClient = NULL;
        reader.release(client);
    }

    if (client) {
        client->decRef();
    }

    me->threadRunning = false;
    me->decRef_Locked();

    unlock();
}
// runSocketCommand is called once for every open client on the
// log reader socket. Here we manage and associated the reader
// client tracking and log region locks LastLogTimes list of
// LogTimeEntrys, and spawn a transitory per-client thread to
// work at filing data to the  socket.
//
// global LogTimeEntry::lock() is used to protect access,
// reference counts are used to ensure that individual
// LogTimeEntry lifetime is managed when not protected.
void FlushCommand::runSocketCommand(SocketClient *client) {
    LogTimeEntry *entry = NULL;
    LastLogTimes &times = mReader.logbuf().mTimes;

    LogTimeEntry::lock();
    LastLogTimes::iterator it = times.begin();
    while(it != times.end()) {
        entry = (*it);
        if (entry->mClient == client) {
            entry->triggerReader_Locked();
            if (entry->runningReader_Locked()) {
                LogTimeEntry::unlock();
                return;
            }
            entry->incRef_Locked();
            break;
        }
        it++;
    }

    if (it == times.end()) {
        // Create LogTimeEntry in notifyNewLog() ?
        if (mTail == (unsigned long) -1) {
            LogTimeEntry::unlock();
            return;
        }
        entry = new LogTimeEntry(mReader, client, mNonBlock, mTail, mLogMask, mPid, mStart);
        times.push_back(entry);
    }

    client->incRef();

    // release client and entry reference counts once done
    entry->startReader_Locked();
    LogTimeEntry::unlock();
}
示例#10
0
void *LogTimeEntry::threadStart(void *obj) {
    prctl(PR_SET_NAME, "logd.reader.per");

    LogTimeEntry *me = reinterpret_cast<LogTimeEntry *>(obj);

    pthread_cleanup_push(threadStop, obj);

    SocketClient *client = me->mClient;
    if (!client) {
        me->error();
        return NULL;
    }

    LogBuffer &logbuf = me->mReader.logbuf();

    bool privileged = FlushCommand::hasReadLogs(client);

    lock();

    while (me->threadRunning && !me->isError_Locked()) {
        uint64_t start = me->mStart;

        unlock();

        if (me->mTail) {
            logbuf.flushTo(client, start, privileged, FilterFirstPass, me);
        }
        start = logbuf.flushTo(client, start, privileged, FilterSecondPass, me);

        lock();

        if (start == LogBufferElement::FLUSH_ERROR) {
            me->error_Locked();
        }

        if (me->mNonBlock || !me->threadRunning || me->isError_Locked()) {
            break;
        }

        me->cleanSkip_Locked();

        pthread_cond_wait(&me->threadTriggeredCondition, &timesLock);
    }

    unlock();

    pthread_cleanup_pop(true);

    return NULL;
}
示例#11
0
// 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();
}
示例#12
0
void LogBuffer::log(log_id_t log_id, log_time realtime,
                    uid_t uid, pid_t pid, pid_t tid,
                    const char *msg, unsigned short len) {
    if ((log_id >= LOG_ID_MAX) || (log_id < 0)) {
        return;
    }
    LogBufferElement *elem = new LogBufferElement(log_id, realtime,
                                                  uid, pid, tid, msg, len);

    pthread_mutex_lock(&mLogElementsLock);

    // Insert elements in time sorted order if possible
    //  NB: if end is region locked, place element at end of list
    LogBufferElementCollection::iterator it = mLogElements.end();
    LogBufferElementCollection::iterator last = it;
    while (--it != mLogElements.begin()) {
        if ((*it)->getRealTime() <= realtime) {
            // halves the peak performance, use with caution
            if (dgram_qlen_statistics) {
                LogBufferElementCollection::iterator ib = it;
                unsigned short buckets, num = 1;
                for (unsigned short i = 0; (buckets = stats.dgram_qlen(i)); ++i) {
                    buckets -= num;
                    num += buckets;
                    while (buckets && (--ib != mLogElements.begin())) {
                        --buckets;
                    }
                    if (buckets) {
                        break;
                    }
                    stats.recordDiff(
                        elem->getRealTime() - (*ib)->getRealTime(), i);
                }
            }
            break;
        }
        last = it;
    }

    if (last == mLogElements.end()) {
        mLogElements.push_back(elem);
    } else {
        log_time end;
        bool end_set = false;
        bool end_always = false;

        LogTimeEntry::lock();

        LastLogTimes::iterator t = mTimes.begin();
        while(t != mTimes.end()) {
            LogTimeEntry *entry = (*t);
            if (entry->owned_Locked()) {
                if (!entry->mNonBlock) {
                    end_always = true;
                    break;
                }
                if (!end_set || (end <= entry->mEnd)) {
                    end = entry->mEnd;
                    end_set = true;
                }
            }
            t++;
        }

        if (end_always
                || (end_set && (end >= (*last)->getMonotonicTime()))) {
            mLogElements.push_back(elem);
        } else {
            mLogElements.insert(last,elem);
        }

        LogTimeEntry::unlock();
    }

    stats.add(len, log_id, uid, pid);
    maybePrune(log_id);
    pthread_mutex_unlock(&mLogElementsLock);
}
示例#13
0
void LogBuffer::log(log_id_t log_id, log_time realtime,
                    uid_t uid, pid_t pid, const char *msg,
                    unsigned short len) {
    if ((log_id >= LOG_ID_MAX) || (log_id < 0)) {
        return;
    }
    LogBufferElement *elem = new LogBufferElement(log_id, realtime,
                                                  uid, pid, msg, len);

    pthread_mutex_lock(&mLogElementsLock);

    // Insert elements in time sorted order if possible
    //  NB: if end is region locked, place element at end of list
    LogBufferElementCollection::iterator it = mLogElements.end();
    LogBufferElementCollection::iterator last = it;
    while (--it != mLogElements.begin()) {
        if ((*it)->getRealTime() <= realtime) {
            break;
        }
        last = it;
    }

    if (last == mLogElements.end()) {
        mLogElements.push_back(elem);
    } else {
        log_time end;
        bool end_set = false;
        bool end_always = false;

        LogTimeEntry::lock();

        LastLogTimes::iterator t = mTimes.begin();
        while(t != mTimes.end()) {
            LogTimeEntry *entry = (*t);
            if (entry->owned_Locked()) {
                if (!entry->mNonBlock) {
                    end_always = true;
                    break;
                }
                if (!end_set || (end <= entry->mEnd)) {
                    end = entry->mEnd;
                    end_set = true;
                }
            }
            t++;
        }

        if (end_always
                || (end_set && (end >= (*last)->getMonotonicTime()))) {
            mLogElements.push_back(elem);
        } else {
            mLogElements.insert(last,elem);
        }

        LogTimeEntry::unlock();
    }

    mSizes[log_id] += len;
    mElements[log_id]++;
    maybePrune(log_id);
    pthread_mutex_unlock(&mLogElementsLock);
}
示例#14
0
// prune "pruneRows" of type "id" from the buffer.
//
// This garbage collection task is used to expire log entries. It is called to
// remove all logs (clear), all UID logs (unprivileged clear), or every
// 256 or 10% of the total logs (whichever is less) to prune the logs.
//
// First there is a prep phase where we discover the reader region lock that
// acts as a backstop to any pruning activity to stop there and go no further.
//
// There are three major pruning loops that follow. All expire from the oldest
// entries. Since there are multiple log buffers, the Android logging facility
// will appear to drop entries 'in the middle' when looking at multiple log
// sources and buffers. This effect is slightly more prominent when we prune
// the worst offender by logging source. Thus the logs slowly loose content
// and value as you move back in time. This is preferred since chatty sources
// invariably move the logs value down faster as less chatty sources would be
// expired in the noise.
//
// The first loop performs blacklisting and worst offender pruning. Falling
// through when there are no notable worst offenders and have not hit the
// region lock preventing further worst offender pruning. This loop also looks
// after managing the chatty log entries and merging to help provide
// statistical basis for blame. The chatty entries are not a notification of
// how much logs you may have, but instead represent how much logs you would
// have had in a virtual log buffer that is extended to cover all the in-memory
// logs without loss. They last much longer than the represented pruned logs
// since they get multiplied by the gains in the non-chatty log sources.
//
// The second loop get complicated because an algorithm of watermarks and
// history is maintained to reduce the order and keep processing time
// down to a minimum at scale. These algorithms can be costly in the face
// of larger log buffers, or severly limited processing time granted to a
// background task at lowest priority.
//
// This second loop does straight-up expiration from the end of the logs
// (again, remember for the specified log buffer id) but does some whitelist
// preservation. Thus whitelist is a Hail Mary low priority, blacklists and
// spam filtration all take priority. This second loop also checks if a region
// lock is causing us to buffer too much in the logs to help the reader(s),
// and will tell the slowest reader thread to skip log entries, and if
// persistent and hits a further threshold, kill the reader thread.
//
// The third thread is optional, and only gets hit if there was a whitelist
// and more needs to be pruned against the backstop of the region lock.
//
// mLogElementsLock must be held when this function is called.
//
bool LogBuffer::prune(log_id_t id, unsigned long pruneRows, uid_t caller_uid) {
    LogTimeEntry *oldest = NULL;
    bool busy = false;
    bool clearAll = pruneRows == ULONG_MAX;

    LogTimeEntry::lock();

    // Region locked?
    LastLogTimes::iterator t = mTimes.begin();
    while(t != mTimes.end()) {
        LogTimeEntry *entry = (*t);
        if (entry->owned_Locked() && entry->isWatching(id)
                && (!oldest || (oldest->mStart > entry->mStart))) {
            oldest = entry;
        }
        t++;
    }

    LogBufferElementCollection::iterator it;

    if (caller_uid != AID_ROOT) {
        // Only here if clearAll condition (pruneRows == ULONG_MAX)
        for(it = mLogElements.begin(); it != mLogElements.end();) {
            LogBufferElement *e = *it;

            if ((e->getLogId() != id) || (e->getUid() != caller_uid)) {
                ++it;
                continue;
            }

            if (oldest && (oldest->mStart <= e->getSequence())) {
                oldest->triggerSkip_Locked(id, pruneRows);
                busy = true;
                break;
            }

            it = erase(it);
            pruneRows--;
        }
        LogTimeEntry::unlock();
        return busy;
    }

    // prune by worst offender by uid
    bool hasBlacklist = mPrune.naughty();
    while (!clearAll && (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 (worstUidEnabledForLogid(id) && mPrune.worstUidEnabled()) {
            std::unique_ptr<const UidEntry *[]> sorted = stats.sort(2, id);

            if (sorted.get()) {
                if (sorted[0] && sorted[1]) {
                    worst_sizes = sorted[0]->getSizes();
                    // Calculate threshold as 12.5% of available storage
                    size_t threshold = log_buffer_size(id) / 8;
                    if (worst_sizes > threshold) {
                        worst = sorted[0]->getKey();
                        second_worst_sizes = sorted[1]->getSizes();
                        if (second_worst_sizes < threshold) {
                            second_worst_sizes = threshold;
                        }
                    }
                }
            }
        }

        // skip if we have neither worst nor naughty filters
        if ((worst == (uid_t) -1) && !hasBlacklist) {
            break;
        }

        bool kick = false;
        bool leading = true;
        it = mLogElements.begin();
        // Perform at least one mandatory garbage collection cycle in following
        // - clear leading chatty tags
        // - coalesce chatty tags
        // - check age-out of preserved logs
        bool gc = pruneRows <= 1;
        if (!gc && (worst != (uid_t) -1)) {
            LogBufferIteratorMap::iterator f = mLastWorstUid[id].find(worst);
            if ((f != mLastWorstUid[id].end())
                    && (f->second != mLogElements.end())) {
                leading = false;
                it = f->second;
            }
        }
        static const timespec too_old = {
            EXPIRE_HOUR_THRESHOLD * 60 * 60, 0
        };
        LogBufferElementCollection::iterator lastt;
        lastt = mLogElements.end();
        --lastt;
        LogBufferElementLast last;
        while (it != mLogElements.end()) {
            LogBufferElement *e = *it;

            if (oldest && (oldest->mStart <= e->getSequence())) {
                busy = true;
                break;
            }

            if (e->getLogId() != id) {
                ++it;
                continue;
            }

            unsigned short dropped = e->getDropped();

            // remove any leading drops
            if (leading && dropped) {
                it = erase(it);
                continue;
            }

            if (dropped && last.coalesce(e, dropped)) {
                it = erase(it, true);
                continue;
            }

            if (hasBlacklist && mPrune.naughty(e)) {
                last.clear(e);
                it = erase(it);
                if (dropped) {
                    continue;
                }

                pruneRows--;
                if (pruneRows == 0) {
                    break;
                }

                if (e->getUid() == worst) {
                    kick = true;
                    if (worst_sizes < second_worst_sizes) {
                        break;
                    }
                    worst_sizes -= e->getMsgLen();
                }
                continue;
            }

            if ((e->getRealTime() < ((*lastt)->getRealTime() - too_old))
                    || (e->getRealTime() > (*lastt)->getRealTime())) {
                break;
            }

            if (dropped) {
                last.add(e);
                if ((!gc && (e->getUid() == worst))
                        || (mLastWorstUid[id].find(e->getUid())
                            == mLastWorstUid[id].end())) {
                    mLastWorstUid[id][e->getUid()] = it;
                }
                ++it;
                continue;
            }

            if (e->getUid() != worst) {
                leading = false;
                last.clear(e);
                ++it;
                continue;
            }

            pruneRows--;
            if (pruneRows == 0) {
                break;
            }

            kick = true;

            unsigned short len = e->getMsgLen();

            // do not create any leading drops
            if (leading) {
                it = erase(it);
            } else {
                stats.drop(e);
                e->setDropped(1);
                if (last.coalesce(e, 1)) {
                    it = erase(it, true);
                } else {
                    last.add(e);
                    if (!gc || (mLastWorstUid[id].find(worst)
                                == mLastWorstUid[id].end())) {
                        mLastWorstUid[id][worst] = it;
                    }
                    ++it;
                }
            }
            if (worst_sizes < second_worst_sizes) {
                break;
            }
            worst_sizes -= len;
        }
        last.clear();

        if (!kick || !mPrune.worstUidEnabled()) {
            break; // the following loop will ask bad clients to skip/drop
        }
    }

    bool whitelist = false;
    bool hasWhitelist = mPrune.nice() && !clearAll;
    it = mLogElements.begin();
    while((pruneRows > 0) && (it != mLogElements.end())) {
        LogBufferElement *e = *it;

        if (e->getLogId() != id) {
            it++;
            continue;
        }

        if (oldest && (oldest->mStart <= e->getSequence())) {
            busy = true;

            if (whitelist) {
                break;
            }

            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(id, pruneRows);
            }
            break;
        }

        if (hasWhitelist && !e->getDropped() && mPrune.nice(e)) { // WhiteListed
            whitelist = true;
            it++;
            continue;
        }

        it = erase(it);
        pruneRows--;
    }

    // Do not save the whitelist if we are reader range limited
    if (whitelist && (pruneRows > 0)) {
        it = mLogElements.begin();
        while((it != mLogElements.end()) && (pruneRows > 0)) {
            LogBufferElement *e = *it;

            if (e->getLogId() != id) {
                ++it;
                continue;
            }

            if (oldest && (oldest->mStart <= e->getSequence())) {
                busy = true;
                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(id, pruneRows);
                }
                break;
            }

            it = erase(it);
            pruneRows--;
        }
    }

    LogTimeEntry::unlock();

    return (pruneRows > 0) && busy;
}
示例#15
0
int LogBuffer::log(log_id_t log_id, log_time realtime,
                   uid_t uid, pid_t pid, pid_t tid,
                   const char *msg, unsigned short len) {
    if ((log_id >= LOG_ID_MAX) || (log_id < 0)) {
        return -EINVAL;
    }

    LogBufferElement *elem = new LogBufferElement(log_id, realtime,
                                                  uid, pid, tid, msg, len);
    int prio = ANDROID_LOG_INFO;
    const char *tag = NULL;
    if (log_id == LOG_ID_EVENTS) {
        tag = android::tagToName(elem->getTag());
    } else {
        prio = *msg;
        tag = msg + 1;
    }
    if (!__android_log_is_loggable(prio, tag, ANDROID_LOG_VERBOSE)) {
        // Log traffic received to total
        pthread_mutex_lock(&mLogElementsLock);
        stats.add(elem);
        stats.subtract(elem);
        pthread_mutex_unlock(&mLogElementsLock);
        delete elem;
        return -EACCES;
    }

    pthread_mutex_lock(&mLogElementsLock);

    // Insert elements in time sorted order if possible
    //  NB: if end is region locked, place element at end of list
    LogBufferElementCollection::iterator it = mLogElements.end();
    LogBufferElementCollection::iterator last = it;
    while (last != mLogElements.begin()) {
        --it;
        if ((*it)->getRealTime() <= realtime) {
            break;
        }
        last = it;
    }

    if (last == mLogElements.end()) {
        mLogElements.push_back(elem);
    } else {
        uint64_t end = 1;
        bool end_set = false;
        bool end_always = false;

        LogTimeEntry::lock();

        LastLogTimes::iterator t = mTimes.begin();
        while(t != mTimes.end()) {
            LogTimeEntry *entry = (*t);
            if (entry->owned_Locked()) {
                if (!entry->mNonBlock) {
                    end_always = true;
                    break;
                }
                if (!end_set || (end <= entry->mEnd)) {
                    end = entry->mEnd;
                    end_set = true;
                }
            }
            t++;
        }

        if (end_always
                || (end_set && (end >= (*last)->getSequence()))) {
            mLogElements.push_back(elem);
        } else {
            mLogElements.insert(last,elem);
        }

        LogTimeEntry::unlock();
    }

    stats.add(elem);
    maybePrune(log_id);
    pthread_mutex_unlock(&mLogElementsLock);

    return len;
}