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diff --git a/impl/antlr/libantlr3c-3.4/doxygen/mainpage.dox b/impl/antlr/libantlr3c-3.4/doxygen/mainpage.dox new file mode 100644 index 0000000..ed52b5e --- /dev/null +++ b/impl/antlr/libantlr3c-3.4/doxygen/mainpage.dox @@ -0,0 +1,104 @@ +// Main page documentation for ANTLR3C runtime. Contains +// doxygen things only. +// + +/// \mainpage ANTLR3 C Runtime API and Usage Guide. +/// +/// \section version Version 3.3.1 +/// +/// This documentation is specifically for the C rutime version 3.1.x.x, which is +/// specifically for use with version 3.1.x.x of the ANTLR recognizer generation +/// tool. While some of the documentation may well apply to prior or future versions +/// you should consult the manuals for the correct version whenever possible. +/// +/// \section chchchchangeesss Changes from 3.2 to 3.3.1 +/// +/// Some changes in 3.3.1 may require small changes in your invoking programs or +/// in the grammar itself. Please read about them here before emailing the user group, +/// where you will be told to come and read about them here, unless they were missed +/// from this list. +/// +/// - \subpage changes331 Check here for API changes +/// +/// \section intro Introduction +/// +/// The ANTLR3 recognizer generation tool is written in Java, but allows the generation +/// of code targeted for a number of other languages. Each target language provides a code +/// generation template for the tool and a runtime library for use by generated recognizers. +/// The C runtime tracks the Java runtime releases and in general when a new version of the +/// tool is released, a new version of the C runtime will be released at the same time. +/// +/// The documentation here is in three parts: +/// +/// - \subpage build Building the runtime itself from source code; +/// - \subpage generate How to tell ANTLR to generate code for the C target; +/// - \subpage buildrec How to build the generated code +/// - \subpage using Using the runtime and the libraries and so on; +/// - \subpage runtime The documentation of the runtime code and functions; +/// +/// \section background Background Information +/// +/// The ANTLR 3 C runtime and code generation templates were written by <a href="http://www.linkedin.com/in/jimidle"> Jim Idle</a> +/// (jimi|at|temporal-wave|dott/com) of <a href="http://www.temporal-wave.com">Temporal Wave LLC</a>. +/// +/// The C runtime and therefore the code generated to utilize the runtime reflects the object model of the +/// Java version of the runtime as closely as a language without class structures and inheritance can. +/// Compromises have only been made where performance would be adversely affected such as minimizing the +/// number of pointer to pointer to pointer to function type structures that could ensue through trying to +/// model inheritance too exactly. Other differences include the use of token and string factories to minimize +/// the number of calls to system functions such as calloc().This model was adopted so that overriding any +/// default implementation of a function is relatively simple for the grammar programmer. +/// +/// The generated code is free threading (subject to the systems calls used on any particular platform +/// being likewise free threading.) +/// +/// \subsection model Runtime Model +/// +/// As there is no such thing as an object reference in C, the runtime defines a number of typedef structs that reflect +/// the calling interface chosen by Terence Parr for the Java version of the same. The initialization of a parser, +/// lexer, input stream or other internal structure therefore consists of allocating the memory required for +/// an instance of the typedef struct that represents the interface, initializing any counters, and buffers etc, +/// then populating a number of pointers to functions that implement the equivalent of the methods in the Java class. +/// +/// The use and initialization of the C versions of a parser is therefore similar to the examples given for Java, +/// but with a bent towards C of course. You may need to be aware of memory allocation and freeing operations +/// in certain environments such as Windows, where you cannot allocate memory in one DLL and free it in another. +/// +/// The runtime provides a number of structures and interfaces that the author has found useful when writing action and +/// processing code within java parsers, and furthermore were required by the C runtime code if it was not to +/// depart too far from the logical layout of the Java model. These include the C equivalents of String, List, +/// Hashtable, Vector and Trie, implemented by pointers to structures. These are freely available for your own programming needs. +/// +/// A goal of the generated code was to minimize the tracking, allocation and freeing of memory for reasons of both +/// performance and reliability. In essence any memory used by a lexer, parser or tree parser is automatically tracked and +/// freed when the instance of it is released. There are therefore factory functions for tokens and so on such that they +/// can be allocated in blocks and parceled out as they are required. They are all then freed in one go, minimizing the +/// risk of memory leaks and alloc/free thrashing. This has only one side effect, being that if you wish to preserve some structure generated by +/// the lexer, parser or tree parser, then you must make a copy of it before freeing those structures, and track it yourself +/// after that. In practice, it is easy enough just not to release the antlr generated components until you are +/// finished with their results. +/// +/// \section targets Target Platforms +/// +/// The C project is constructed such that it will compile on any reasonable ANSI C compiler in either 64 or 32 bit mode, +/// with all warnings turned on. This is true of both the runtime code and the generated code and has been summarily tested +/// with Visual Studio .Net (2003, 2005 and 2008) and later versions of gcc on Redhat Linux, as well as on AIX 5.2/5.3, Solaris 9/10, +/// HPUX 11.xx, OSX (PowerPC and Intel) and Cygwin. +/// +/// \b Notes +/// - The C runtime is constructed such that the library can be integrated as an archive library, or a shared library/DLL. +/// - The C language target code generation templates are distributed with the source code for the ANTLR tool itself. +/// +/// \section performance Performance +/// +/// It is C :-). Basic testing of performance against the Java runtime, +/// using the JDK1.6 java source code, and the Java parser provided in the examples (which is a tough test as it includes +/// backtracking and memoization) show that the C runtime uses about half the memory and is between 2 and 3 times the speed. +/// Tests of non-backtracking, non-memoizing parsers, indicate results significantly better than this. +/// +/// \section examples Downloading Examples +/// +/// The <a href="http://www.antlr.org/download.html">downloads page</a> of the ANTLR web site contains a downloadable +/// zip/tar of examples projects for use with the C runtime model. It contains .sln files and source code for a +/// number of example grammars and helps to see how to invoke and call the generated recognizers. +///
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