| /* |
| * 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 <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; |
| |
| #endif // SHARE_VM_UTILITIES_FORMATBUFFER_HPP |