logd/LogStatistics.h

/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _LOGD_LOG_STATISTICS_H__
#define _LOGD_LOG_STATISTICS_H__

#include <sys/types.h>

#include <log/log.h>
#include <utils/BasicHashtable.h>

#include "LogBufferElement.h"

#define log_id_for_each(i) \
    for (log_id_t i = LOG_ID_MIN; i < LOG_ID_MAX; i = (log_id_t) (i + 1))

struct UidEntry {
    const uid_t uid;
    size_t size;

    UidEntry(uid_t uid):uid(uid),size(0) { }

    inline const uid_t&getKey() const { return uid; }
    size_t getSizes() const { return size; }
    inline void add(size_t s) { size += s; }
    inline bool subtract(size_t s) { size -= s; return !size; }
};

// Log Statistics
class LogStatistics {
    size_t mSizes[LOG_ID_MAX];
    size_t mElements[LOG_ID_MAX];
    size_t mSizesTotal[LOG_ID_MAX];
    size_t mElementsTotal[LOG_ID_MAX];

    // uid to size list
    typedef android::BasicHashtable<uid_t, UidEntry> uidTable_t;
    uidTable_t uidTable[LOG_ID_MAX];

public:
    LogStatistics();

    void enableStatistics() { }

    void add(LogBufferElement *entry);
    void subtract(LogBufferElement *entry);

    // Caller must delete array
    const UidEntry **sort(size_t n, log_id i);

    // fast track current value by id only
    size_t sizes(log_id_t id) const { return mSizes[id]; }
    size_t elements(log_id_t id) const { return mElements[id]; }
    size_t sizesTotal(log_id_t id) const { return mSizesTotal[id]; }
    size_t elementsTotal(log_id_t id) const { return mElementsTotal[id]; }

    // *strp = malloc, balance with free
    void format(char **strp, uid_t uid, unsigned int logMask);

    // helper
    char *pidToName(pid_t pid);
    uid_t pidToUid(pid_t pid);
    char *uidToName(uid_t uid);
};

#endif // _LOGD_LOG_STATISTICS_H__