/** @file * IPRT - C++ Representational State Transfer (REST) Output Classes. */ /* * Copyright (C) 2008-2019 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. * * The contents of this file may alternatively be used under the terms * of the Common Development and Distribution License Version 1.0 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the * VirtualBox OSE distribution, in which case the provisions of the * CDDL are applicable instead of those of the GPL. * * You may elect to license modified versions of this file under the * terms and conditions of either the GPL or the CDDL or both. */ #ifndef IPRT_INCLUDED_cpp_restoutput_h #define IPRT_INCLUDED_cpp_restoutput_h #ifndef RT_WITHOUT_PRAGMA_ONCE # pragma once #endif #include #include #include #include /** @defgroup grp_rt_cpp_restoutput C++ Representational State Transfer (REST) Output Classes. * @ingroup grp_rt_cpp * @{ */ /** * Abstract base class for serializing data objects. */ class RT_DECL_CLASS RTCRestOutputBase { public: RTCRestOutputBase() RT_NOEXCEPT; virtual ~RTCRestOutputBase(); /** * Raw output function. * * @returns Number of bytes outputted. * @param a_pchString The string to output (not necessarily terminated). * @param a_cchToWrite The length of the string */ virtual size_t output(const char *a_pchString, size_t a_cchToWrite) RT_NOEXCEPT = 0; /** * RTStrPrintf like function (see @ref pg_rt_str_format). * * @returns Number of bytes outputted. * @param pszFormat The format string. * @param ... Argument specfied in @a pszFormat. */ inline size_t printf(const char *pszFormat, ...) RT_NOEXCEPT RT_IPRT_FORMAT_ATTR(2, 3) { va_list va; va_start(va, pszFormat); size_t cchWritten = this->vprintf(pszFormat, va); va_end(va); return cchWritten; } /** * RTStrPrintfV like function (see @ref pg_rt_str_format). * * @returns Number of bytes outputted. * @param pszFormat The format string. * @param va Argument specfied in @a pszFormat. */ size_t vprintf(const char *pszFormat, va_list va) RT_NOEXCEPT RT_IPRT_FORMAT_ATTR(2, 0); /** * Begins an array. * @returns Previous output state. Pass to endArray() when done. */ virtual uint32_t beginArray() RT_NOEXCEPT; /** * Ends an array. * @param a_uOldState Previous output state (returned by beginArray()). */ virtual void endArray(uint32_t a_uOldState) RT_NOEXCEPT; /** * Begins an object. * @returns Previous output state. Pass to endObject() when done. */ virtual uint32_t beginObject() RT_NOEXCEPT; /** * Ends an array. * @param a_uOldState Previous output state (returned by beginObject()). */ virtual void endObject(uint32_t a_uOldState) RT_NOEXCEPT; /** * Outputs a value separator. * This is called before a value, not after. */ virtual void valueSeparator() RT_NOEXCEPT; /** * Outputs a value separator, name and name separator. */ virtual void valueSeparatorAndName(const char *a_pszName, size_t a_cchName) RT_NOEXCEPT; /** Outputs a null-value. */ void nullValue() RT_NOEXCEPT; protected: /** The current indentation level (bits 15:0) and separator state (bit 31). */ uint32_t m_uState; /** @callback_method_impl{FNRTSTROUTPUT} */ static DECLCALLBACK(size_t) printfOutputCallback(void *pvArg, const char *pachChars, size_t cbChars) RT_NOEXCEPT; }; /** * Abstract base class for pretty output. */ class RT_DECL_CLASS RTCRestOutputPrettyBase : public RTCRestOutputBase { public: RTCRestOutputPrettyBase() RT_NOEXCEPT; virtual ~RTCRestOutputPrettyBase(); /** * Begins an array. * @returns Previous output state. Pass to endArray() when done. */ virtual uint32_t beginArray() RT_NOEXCEPT RT_OVERRIDE; /** * Ends an array. * @param a_uOldState Previous output state (returned by beginArray()). */ virtual void endArray(uint32_t a_uOldState) RT_NOEXCEPT RT_OVERRIDE; /** * Begins an object. * @returns Previous output state. Pass to endObject() when done. */ virtual uint32_t beginObject() RT_NOEXCEPT RT_OVERRIDE; /** * Ends an array. * @param a_uOldState Previous output state (returned by beginObject()). */ virtual void endObject(uint32_t a_uOldState) RT_NOEXCEPT RT_OVERRIDE; /** * Outputs a value separator. * This is called before a value, not after. */ virtual void valueSeparator() RT_NOEXCEPT RT_OVERRIDE; /** * Outputs a value separator, name and name separator. */ virtual void valueSeparatorAndName(const char *a_pszName, size_t a_cchName) RT_NOEXCEPT RT_OVERRIDE; protected: /** Helper for outputting the correct amount of indentation. */ void outputIndentation() RT_NOEXCEPT; }; /** * Serialize to a string object. */ class RT_DECL_CLASS RTCRestOutputToString : public RTCRestOutputBase { public: /** * Creates an instance that appends to @a a_pDst. * @param a_pDst Pointer to the destination string object. * NULL is not accepted and will assert. * @param a_fAppend Whether to append to the current string value, or * nuke the string content before starting the output. */ RTCRestOutputToString(RTCString *a_pDst, bool a_fAppend = false) RT_NOEXCEPT; virtual ~RTCRestOutputToString(); virtual size_t output(const char *a_pchString, size_t a_cchToWrite) RT_NOEXCEPT RT_OVERRIDE; /** * Finalizes the output and releases the string object to the caller. * * @returns The released string object. NULL if we ran out of memory or if * called already. * * @remark This sets m_pDst to NULL and the object cannot be use for any * more output afterwards. */ virtual RTCString *finalize() RT_NOEXCEPT; protected: /** Pointer to the destination string. NULL after finalize(). */ RTCString *m_pDst; /** Set if we ran out of memory and should ignore subsequent calls. */ bool m_fOutOfMemory; /* Make non-copyable (RTCNonCopyable causes warnings): */ RTCRestOutputToString(RTCRestOutputToString const &); RTCRestOutputToString *operator=(RTCRestOutputToString const &); }; /** * Serialize pretty JSON to a string object. */ class RT_DECL_CLASS RTCRestOutputPrettyToString : public RTCRestOutputPrettyBase { public: /** * Creates an instance that appends to @a a_pDst. * @param a_pDst Pointer to the destination string object. * NULL is not accepted and will assert. * @param a_fAppend Whether to append to the current string value, or * nuke the string content before starting the output. */ RTCRestOutputPrettyToString(RTCString *a_pDst, bool a_fAppend = false) RT_NOEXCEPT; virtual ~RTCRestOutputPrettyToString(); virtual size_t output(const char *a_pchString, size_t a_cchToWrite) RT_NOEXCEPT RT_OVERRIDE; /** * Finalizes the output and releases the string object to the caller. * * @returns The released string object. NULL if we ran out of memory or if * called already. * * @remark This sets m_pDst to NULL and the object cannot be use for any * more output afterwards. */ virtual RTCString *finalize() RT_NOEXCEPT; protected: /** Pointer to the destination string. NULL after finalize(). */ RTCString *m_pDst; /** Set if we ran out of memory and should ignore subsequent calls. */ bool m_fOutOfMemory; /* Make non-copyable (RTCNonCopyable causes warnings): */ RTCRestOutputPrettyToString(RTCRestOutputToString const &); RTCRestOutputPrettyToString *operator=(RTCRestOutputToString const &); }; /** @} */ #endif /* !IPRT_INCLUDED_cpp_restoutput_h */