src/hotspot/share/utilities/formatBuffer.hpp

*** 1,7 ****
  /*
!  * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
   * 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.
--- 1,7 ----
  /*
!  * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
   * 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.
*** 61,74 ****
    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;
--- 61,97 ----
    char* buffer() { return _buf; }
    int size() { return bufsz; }
  
   private:
    FormatBuffer(const FormatBuffer &); // prevent copies
  
   protected:
+   char _buffer[bufsz];
    inline FormatBuffer();
+   inline void appendv(const char* format, va_list ap)  ATTRIBUTE_PRINTF(2, 0);
+ };
+ 
+ // Use malloc'ed buffer if static buffer is not enough.
+ template <size_t bufsz = FormatBufferBase::BufferSize>
+ class FormatBufferEx : public FormatBuffer<bufsz> {
+  public:
+   inline FormatBufferEx();
+   ~FormatBufferEx(){
+     if (_dyn_buffer != NULL) {
+       ::free(_dyn_buffer);
+     }
+   }
+   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 argp) ATTRIBUTE_PRINTF(2, 0);
+ 
+   int size() { return _buffer_size; }
+ 
+  private:
+   inline void prepare_buffer(bool is_append, const char* format, va_list argp);
+   char *_dyn_buffer;
+   size_t _buffer_size;
  };
  
  template <size_t bufsz>
  FormatBuffer<bufsz>::FormatBuffer(const char * format, ...) : FormatBufferBase(_buffer) {
    va_list argp;
*** 100,117 ****
    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;
--- 123,194 ----
    jio_vsnprintf(_buf, bufsz, format, argp);
  }
  
  template <size_t bufsz>
  void FormatBuffer<bufsz>::append(const char* format, ...) {
+   va_list argp;
+   va_start(argp, format);
+   appendv(format, argp);
+   va_end(argp);
+ }
+ 
+ template <size_t bufsz>
+ void FormatBuffer<bufsz>::appendv(const char* format, va_list argp) {
    // 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;
  
+   jio_vsnprintf(buf_end, bufsz - len, format, argp);
+ }
+ 
+ template <size_t bufsz>
+ FormatBufferEx<bufsz>::FormatBufferEx() : FormatBuffer<bufsz>(), _dyn_buffer(NULL), _buffer_size(bufsz) {
+   // Do nothing.
+ }
+ 
+ template <size_t bufsz>
+ void FormatBufferEx<bufsz>::print(const char * format, ...) {
    va_list argp;
    va_start(argp, format);
!   printv(format, argp);
!   va_end(argp);
! }
! 
! template <size_t bufsz>
! void FormatBufferEx<bufsz>::prepare_buffer(bool is_append, const char * format, va_list argp) {
!   size_t len = jio_vsnprintf(NULL, 0, format, argp) + 1;
!   if (is_append) {
!     len += strlen(FormatBufferBase::_buf);
!   }
!   if (len > _buffer_size) {
!     _dyn_buffer = (_dyn_buffer == NULL) ? (char *)::malloc(len)
!                                         : (char *)::realloc(_dyn_buffer, len);
!     FormatBufferBase::_buf = _dyn_buffer;
!     _buffer_size = len;
!   }
! }
! 
! template <size_t bufsz>
! void FormatBufferEx<bufsz>::printv(const char * format, va_list argp) {
!   va_list argp_local;
!   va_copy(argp_local, argp);
!   prepare_buffer(false, format, argp_local);
!   va_end(argp_local);
! 
!   jio_vsnprintf(FormatBufferBase::_buf, _buffer_size, format, argp);
! }
! 
! template <size_t bufsz>
! void FormatBufferEx<bufsz>::append(const char* format, ...) {
!   va_list argp, argp_prepare;
!   va_start(argp, format);
!   va_copy(argp_prepare, argp);
!   prepare_buffer(true, format, argp_prepare);
!   va_end(argp_prepare);
! 
!   FormatBuffer<bufsz>::appendv(format, argp);
    va_end(argp);
  }
  
  // Used to format messages.
  typedef FormatBuffer<> err_msg;