C++ StringBuffer::reserve方法代码示例

inline size32_t readFile(const char* name,StringBuffer& buf)
{
    size32_t sz = 0;
#ifdef _WIN32
    int fd = open(name,O_RDONLY|O_BINARY);
    if(fd)
    {
        struct _stat st;
        if(!_fstat(fd,&st))
        {
            void * data = buf.reserve((size32_t)st.st_size);
            sz = read(fd, data, st.st_size);
        }
        close(fd);
    }
#else
    int fd = open(name,O_RDONLY);
    if(fd)
    {
        struct stat st;
        if(!fstat(fd,&st))
        {
            void * data = buf.reserve((size32_t)st.st_size);
            sz = read(fd, data, st.st_size);
        }
        close(fd);
    }
#endif
    return sz;
}

static bool
EscapeNakedForwardSlashes(StringBuffer &sb, const CharT *oldChars, size_t oldLen)
{
    for (const CharT *it = oldChars; it < oldChars + oldLen; ++it) {
        if (*it == '/' && (it == oldChars || it[-1] != '\\')) {
            /* There's a forward slash that needs escaping. */
            if (sb.empty()) {
                /* This is the first one we've seen, copy everything up to this point. */
                if (mozilla::IsSame<CharT, jschar>::value && !sb.ensureTwoByteChars())
                    return false;

                if (!sb.reserve(oldLen + 1))
                    return false;

                sb.infallibleAppend(oldChars, size_t(it - oldChars));
            }
            if (!sb.append('\\'))
                return false;
        }

        if (!sb.empty() && !sb.append(*it))
            return false;
    }

    return true;
}

int main()
{
	StringBuffer *a = new StringBuffer();
	a->reserve(2);

	cout << "Creating a String Buffer a \n\n";

	a->append('S');

	cout << "Copying String Buffer a to String Buffer b using Copy Constructor\n\n";

	StringBuffer *b = new StringBuffer(*a);

	cout << "Length of a is: ";
	cout << a->length() << endl << endl;
	cout << "Length of b is: ";
	cout << b->length() << endl << endl;

	cout << "That clearly shows resources are owned by b now!" << endl << endl;

	//CopyTest();
	//CharSToStringBufferTest();

	return 0;
}

static MOZ_ALWAYS_INLINE bool
SetupBuffer(StringBuffer& sb, const CharT* oldChars, size_t oldLen, const CharT* it)
{
    if (mozilla::IsSame<CharT, char16_t>::value && !sb.ensureTwoByteChars())
        return false;

    if (!sb.reserve(oldLen + 1))
        return false;

    sb.infallibleAppend(oldChars, size_t(it - oldChars));
    return true;
}

char* FolderData::format() {

    StringBuffer out;

    out.reserve(150);

    out = "<Folder>\n";
    if (name.length() > 0)
        out += XMLProcessor::makeElement(FOLDER_NAME, name);
    if (created.length() > 0)
        out += XMLProcessor::makeElement(FOLDER_CREATED, created);
    if (modified.length() > 0)
        out += XMLProcessor::makeElement(FOLDER_MODIFIED, modified);
    if (accessed.length() > 0)
        out += XMLProcessor::makeElement(FOLDER_ACCESSED, accessed);

    StringBuffer attributes;

    if (isHiddenPresent)
        attributes += XMLProcessor::makeElement(FOLDER_HIDDEN, hidden);
    if (isSystemPresent)
        attributes += XMLProcessor::makeElement(FOLDER_SYSTEM, system);
    if (isArchivedPresent)
        attributes += XMLProcessor::makeElement(FOLDER_ARCHIVED, archived);
    if (isDeletedPresent)
        attributes += XMLProcessor::makeElement(FOLDER_DELETE, deleted);
    if (isWritablePresent)
        attributes += XMLProcessor::makeElement(FOLDER_WRITABLE, writable);
    if (isReadablePresent)
        attributes += XMLProcessor::makeElement(FOLDER_READABLE, readable);
    if (isExecutablePresent)
        attributes += XMLProcessor::makeElement(FOLDER_EXECUTABLE, executable);

    if (!attributes.empty())
        out += XMLProcessor::makeElement(FOLDER_ATTRIBUTES, attributes);

    if (role.length() > 0)
        out += XMLProcessor::makeElement(FOLDER_ROLE, role);

    if (!(extended.isEmpty())){
        for(int i=0; i < extended.size(); i++){
            const char* temp =  ((FolderExt*)extended.get(i))->format();
            out += temp;
            delete [] temp;
        }
    }

    out += "</Folder>\n";
    return stringdup(out.c_str());
}

bool SslClientConnection::readClientConnection (StringBuffer& stringBuffer, bool& progress) {
  if (_ssl == nullptr || ! _isConnected) {
    return false;
  }

  progress = false;

  do {

again:
    // reserve some memory for reading
    if (stringBuffer.reserve(READBUFFER_SIZE) == TRI_ERROR_OUT_OF_MEMORY) {
      // out of memory
      TRI_set_errno(TRI_ERROR_OUT_OF_MEMORY);
      return false;
    }

    int lenRead = SSL_read(_ssl, stringBuffer.end(), READBUFFER_SIZE - 1);

    switch (SSL_get_error(_ssl, lenRead)) {
      case SSL_ERROR_NONE:
        progress = true;
        stringBuffer.increaseLength(lenRead);
        break;

      case SSL_ERROR_ZERO_RETURN:
        SSL_shutdown(_ssl);
        _isConnected = false;
        return true;

      case SSL_ERROR_WANT_READ:
        goto again;

      case SSL_ERROR_WANT_WRITE:
      case SSL_ERROR_WANT_CONNECT:
      case SSL_ERROR_SYSCALL:
      default:
        /* unexpected */
        return false;
    }
  }
  while (readable());

  return true;
}

      void slurp (string const& filename, StringBuffer& result) {
        int fd = TRI_OPEN(filename.c_str(), O_RDONLY);

        if (fd == -1) {
          THROW_FILE_OPEN_ERROR("open", filename, "O_RDONLY", errno);
        }
        
        // reserve space in the output buffer
        off_t fileSize = size(filename);
        if (fileSize > 0) {
          result.reserve((size_t) fileSize);
        }

        char buffer[10240];

        while (true) {
          ssize_t n = TRI_READ(fd, buffer, sizeof(buffer));

          if (n == 0) {
            break;
          }

          if (n < 0) {
            TRI_CLOSE(fd);
            LOG_TRACE("read failed for '%s' with %s and result %d on fd %d",
                      filename.c_str(),
                      strerror(errno),
                      (int) n,
                      fd); 
            THROW_FILE_FUNC_ERROR("read", "", errno);
          }

          result.appendText(buffer, n);
        }

        TRI_CLOSE(fd);
      }

char *MailData::format() {
    StringBuffer out;

    out.reserve(150);

    out = "<Email>\n";
    out += XMLProcessor::makeElement(EMAIL_READ, read);
    out += XMLProcessor::makeElement(EMAIL_FORW, forwarded);
    out += XMLProcessor::makeElement(EMAIL_REPL, replied);
    out += XMLProcessor::makeElement(EMAIL_TREC, received);
    out += XMLProcessor::makeElement(EMAIL_TCRE, created);
    out += XMLProcessor::makeElement(EMAIL_TMOD, modified);
    out += XMLProcessor::makeElement(EMAIL_DELE, deleted);
    out += XMLProcessor::makeElement(EMAIL_FLAG, flagged);
    char *item = emailItem.format();
    if ( item ) {
    out += "<emailitem>\n<![CDATA[";
        out += item;
        delete [] item;
        out += "]]&gt;\n</emailitem>\n";
    }
    out += "</Email>\n";
    return stringdup(out.c_str());
}

//-----------------------------------------------------
//
//-----------------------------------------------------
int main(int argc, char* argv[])
{
#ifdef _NO_LDAP
    fprintf(stderr, "System was built with _NO_LDAP\n");
    return -1;
#endif

    for (int x = 1; x < argc; x++)
    {
        if (0==strncmp("-h", argv[x], 2))
        {
            usage();
            exit(0);
        }
        else
        {
            fprintf(stderr, "\nERROR: Unrecognized parameter : '%s', enter 'initldap -h' for help\n", argv[x]);
            exit(1);
        }
    }

    InitModuleObjects();

    //execute configgen to query the LDAP Server configuration(s)
    StringBuffer cmd;
    cmd.appendf("%s%cconfiggen -env %s%c%s -listldapservers", ADMIN_DIR,PATHSEPCHAR,CONFIG_DIR, PATHSEPCHAR, ENV_XML_FILE);

    char * configBuffer = NULL;

    //acquire LDAP configuration by executing configgen and capturing output
    {
        StringBuffer configBuff;
        Owned<IPipeProcess> pipe = createPipeProcess();
        if (pipe->run("configgen", cmd.str(), ".", false, true, true, 0))
        {
            Owned<ISimpleReadStream> pipeReader = pipe->getOutputStream();
            const size32_t chunkSize = 8192;
            for (;;)
            {
                size32_t sizeRead = pipeReader->read(chunkSize, configBuff.reserve(chunkSize));
                if (sizeRead < chunkSize)
                {
                    configBuff.setLength(configBuff.length() - (chunkSize - sizeRead));
                    break;
                }
            }
            pipe->closeOutput();
        }
        int retcode = pipe->wait();
        if (retcode)
        {
            fprintf(stderr, "\nERROR %d: unable to execute %s", retcode, cmd.str());
            exit(1);
        }
        configBuffer = strdup(configBuff.str());
    }

    //Using the LDAP Server parms queried from configgen, build an
    //LDAPSecurity property tree for each LDAP Server and call the LDAP
    //Security Manager to create the needed entries
    Owned<IPropertyTree> ldapProps;
    char *saveptr;
    char * pLine = strtok_r(configBuffer, "\n", &saveptr);
    while (pLine)
    {
        if (pLine && 0==strcmp(pLine, "LDAPServerProcess"))
        {
            if (ldapProps)
                initLDAP(ldapProps);
            ldapProps.clear();
            ldapProps.setown(createPTree("ldapSecurity"));
        }
        else
        {
            char * sep = strchr(pLine, ',');
            if (sep)
            {
                *sep = (char)NULL;
                ldapProps->addProp(pLine, sep+1);
            }
        }
        pLine = strtok_r(NULL, "\n", &saveptr);
    }
    if (ldapProps)
        initLDAP(ldapProps);
    if (configBuffer)
        free(configBuffer);
    ldapProps.clear();

    releaseAtoms();
    return 0;
}

bool SslClientConnection::readClientConnection (StringBuffer& stringBuffer, 
                                                bool& connectionClosed) {
#ifdef _WIN32
  char windowsErrorBuf[256];
#endif

  connectionClosed = true;
  if (_ssl == nullptr) {
    return false;
  }
  if (! _isConnected) {
    return true;
  }

  connectionClosed = false;

  do {

again:
    // reserve some memory for reading
    if (stringBuffer.reserve(READBUFFER_SIZE) == TRI_ERROR_OUT_OF_MEMORY) {
      // out of memory
      TRI_set_errno(TRI_ERROR_OUT_OF_MEMORY);
      return false;
    }

    ERR_clear_error();

    int lenRead = SSL_read(_ssl, stringBuffer.end(), READBUFFER_SIZE - 1);

    switch (SSL_get_error(_ssl, lenRead)) {
      case SSL_ERROR_NONE:
        stringBuffer.increaseLength(lenRead);
        break;

      case SSL_ERROR_ZERO_RETURN:
        connectionClosed = true;
        SSL_shutdown(_ssl);
        _isConnected = false;
        return true;

      case SSL_ERROR_WANT_READ:
        goto again;

      case SSL_ERROR_WANT_WRITE:
      case SSL_ERROR_WANT_CONNECT:
      case SSL_ERROR_SYSCALL:
      default: {
        char const* pErr = STR_ERROR();
        int errorDetail = ERR_get_error();
        char errorBuffer[256];
        ERR_error_string_n(errorDetail, errorBuffer, sizeof(errorBuffer));
        _errorDetails = std::string("SSL: while reading: error '") + std::to_string(errno) + 
          std::string("' - ") + errorBuffer + std::string("' - ") + pErr;

        /* unexpected */
        connectionClosed = true;
        return false;
      }
    }
  }
  while (readable());

  return true;
}