/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "jvm.h"

#include "utilities/globalDefinitions.hpp"

#include <stdarg.h>

// Simple class to format the ctor arguments into a fixed-sized buffer.

class FormatBufferBase {

 protected:

  char* _buf;

  inline FormatBufferBase(char* buf) : _buf(buf) {}

 public:

  static const int BufferSize = 256;

  operator const char *() const { return _buf; }

};

// Use resource area for buffer

class FormatBufferResource : public FormatBufferBase {

 public:

  FormatBufferResource(const char * format, ...) ATTRIBUTE_PRINTF(2, 3);

};

class FormatBufferDummy {};

// Use stack for buffer

template <size_t bufsz = FormatBufferBase::BufferSize>

class FormatBuffer : public FormatBufferBase {

 public:

  inline FormatBuffer(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);

  // since va_list is unspecified type (can be char*), we use FormatBufferDummy to disambiguate these constructors

  inline FormatBuffer(FormatBufferDummy dummy, const char* format, va_list ap) ATTRIBUTE_PRINTF(3, 0);

  inline void append(const char* format, ...)  ATTRIBUTE_PRINTF(2, 3);

  inline void print(const char* format, ...)  ATTRIBUTE_PRINTF(2, 3);

  inline void printv(const char* format, va_list ap) ATTRIBUTE_PRINTF(2, 0);

  char* buffer() { return _buf; }

  int size() { return bufsz; }

 private:

  FormatBuffer(const FormatBuffer &); // prevent copies

  char _buffer[bufsz];

 protected:

  inline FormatBuffer();

};

template <size_t bufsz>

FormatBuffer<bufsz>::FormatBuffer(const char * format, ...) : FormatBufferBase(_buffer) {

  va_list argp;

  va_start(argp, format);

  jio_vsnprintf(_buf, bufsz, format, argp);

  va_end(argp);

}

template <size_t bufsz>

FormatBuffer<bufsz>::FormatBuffer(FormatBufferDummy dummy, const char * format, va_list ap) : FormatBufferBase(_buffer) {

  jio_vsnprintf(_buf, bufsz, format, ap);

}

template <size_t bufsz>

FormatBuffer<bufsz>::FormatBuffer() : FormatBufferBase(_buffer) {

  _buf[0] = '\0';

}

template <size_t bufsz>

void FormatBuffer<bufsz>::print(const char * format, ...) {

  va_list argp;

  va_start(argp, format);

  jio_vsnprintf(_buf, bufsz, format, argp);

  va_end(argp);

}

template <size_t bufsz>

void FormatBuffer<bufsz>::printv(const char * format, va_list argp) {

  jio_vsnprintf(_buf, bufsz, format, argp);

}

template <size_t bufsz>

void FormatBuffer<bufsz>::append(const char* format, ...) {

  // Given that the constructor does a vsnprintf we can assume that

  // _buf is already initialized.

  size_t len = strlen(_buf);

  char* buf_end = _buf + len;

  va_list argp;

  va_start(argp, format);

  jio_vsnprintf(buf_end, bufsz - len, format, argp);

  va_end(argp);

}

// Used to format messages.

typedef FormatBuffer<> err_msg;