Method readDictionaryFragment

runtime/Log.cc:979–1064

* Reads a partial dictionary from the log file and adds it to the global * mapping of log identifiers to static log information. * * \param fd * File descriptor to read the mapping from * \return * true indicates success; false indicates error */

 *      true indicates success; false indicates error
 */
bool
Log::Decoder::readDictionaryFragment(FILE *fd) {
    // These buffers start us off with some statically allocated space.
    // Should we need more, we will malloc it.
    size_t bufferSize = 10*1024;
    char filenameBuffer[bufferSize];
    char formatBuffer[bufferSize];

    bool newBuffersAllocated = false;
    char *filename = filenameBuffer;
    char *format = formatBuffer;

    DictionaryFragment df;
    size_t bytesRead = fread(&df, 1, sizeof(DictionaryFragment), fd);
    if (bytesRead != sizeof(DictionaryFragment)) {
        fprintf(stderr, "Could not read entire dictionary fragment header\r\n");
        return false;
    }

    assert(df.entryType == EntryType::LOG_MSGS_OR_DIC);

    while (bytesRead < df.newMetadataBytes && !feof(fd)) {
        CompressedLogInfo cli;
        size_t newBytesRead = 0;
        newBytesRead += fread(&cli, 1, sizeof(CompressedLogInfo), fd);

        if (newBytesRead != sizeof(CompressedLogInfo)) {
            fprintf(stderr, "Could not read in log metadata\r\n");
            return false;
        }

        if (bufferSize < cli.filenameLength ||
            bufferSize < cli.formatStringLength)
        {
            if (newBuffersAllocated) {
                free(filename);
                free(format);
                filename = format = nullptr;
            }

            newBuffersAllocated = true;
            bufferSize = 2*std::max(cli.filenameLength, cli.formatStringLength);
            filename = static_cast<char*>(malloc(bufferSize));
            format = static_cast<char*>(malloc(bufferSize));

            if (filename == nullptr || format == nullptr) {
                fprintf(stderr, "Internal Error: Could not allocate enough "
                               "memory to store the filename/format strings "
                               "in the dictionary. Tried to allocate %lu bytes "
                               "to store the %u and %u byte filename and "
                               "format string lengths respectively",
                               bufferSize,
                               cli.formatStringLength,
                               cli.filenameLength);
                return false;
            }
        }