--- /dev/null 2017-05-19 14:48:27.437288209 -0400 +++ new/src/share/vm/utilities/formatBuffer.hpp 2017-06-16 19:50:53.099114044 -0400 @@ -0,0 +1,119 @@ +/* + * 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. + * + * 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. + * + */ + +#ifndef SHARE_VM_UTILITIES_FORMATBUFFER_HPP +#define SHARE_VM_UTILITIES_FORMATBUFFER_HPP + +#include "utilities/globalDefinitions.hpp" +#include "prims/jvm.h" +#include + +// 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 +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 +FormatBuffer::FormatBuffer(const char * format, ...) : FormatBufferBase(_buffer) { + va_list argp; + va_start(argp, format); + jio_vsnprintf(_buf, bufsz, format, argp); + va_end(argp); +} + +template +FormatBuffer::FormatBuffer(FormatBufferDummy dummy, const char * format, va_list ap) : FormatBufferBase(_buffer) { + jio_vsnprintf(_buf, bufsz, format, ap); +} + +template +FormatBuffer::FormatBuffer() : FormatBufferBase(_buffer) { + _buf[0] = '\0'; +} + +template +void FormatBuffer::print(const char * format, ...) { + va_list argp; + va_start(argp, format); + jio_vsnprintf(_buf, bufsz, format, argp); + va_end(argp); +} + +template +void FormatBuffer::printv(const char * format, va_list argp) { + jio_vsnprintf(_buf, bufsz, format, argp); +} + +template +void FormatBuffer::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; + +#endif // SHARE_VM_UTILITIES_FORMATBUFFER_HPP