Function read_proc_memory

src/bvar/default_variables.cpp:215–255

};

static bool read_proc_memory(ProcMemory &m) {
    m = ProcMemory();
    errno = 0;
#if defined(OS_LINUX)
    butil::ScopedFILE fp("/proc/self/statm", "r");
    if (NULL == fp) {
        PLOG_ONCE(WARNING) << "Fail to open /proc/self/statm";
        return false;
    }
    if (fscanf(fp, "%ld %ld %ld %ld %ld %ld %ld",
               &m.size, &m.resident, &m.share,
               &m.trs, &m.lrs, &m.drs, &m.dt) != 7) {
        PLOG(WARNING) << "Fail to fscanf /proc/self/statm";
        return false;
    }
    return true;
#elif defined(OS_MACOSX)
    // TODO(zhujiashun): get remaining memory info in MacOS.
    memset(&m, 0, sizeof(m));
    static pid_t pid = getpid();
    static int64_t pagesize = getpagesize();
    std::ostringstream oss;
    char cmdbuf[128];
    snprintf(cmdbuf, sizeof(cmdbuf), "ps -p %ld -o rss=,vsz=", (long)pid);
    if (butil::read_command_output(oss, cmdbuf) != 0) {
        LOG(ERROR) << "Fail to read memory state";
        return false;
    }
    const std::string& result = oss.str();
    if (sscanf(result.c_str(), "%ld %ld", &m.resident, &m.size) != 2) {
        PLOG(WARNING) << "Fail to sscanf";
        return false;
    }
    // resident and size in Kbytes
    m.resident = m.resident * 1024 / pagesize;
    m.size = m.size * 1024 / pagesize;
    return true;
#else
    return false;
#endif
}

class ProcMemoryReader {
public: