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diff --git a/antlr-3.4/runtime/C/doxygen/buildrec.dox b/antlr-3.4/runtime/C/doxygen/buildrec.dox new file mode 100644 index 0000000..816a845 --- /dev/null +++ b/antlr-3.4/runtime/C/doxygen/buildrec.dox @@ -0,0 +1,269 @@ +/// \page buildrec How to build Generated C Code +/// +/// \section generated Generated Files +/// +/// The antlr tool jar, run against a grammar file that targets the C language, will generate the following files +/// according to whether your grammar file contains a lexer, parser, combined or treeparser specification. +/// Your grammar file name and the subject of the grammar line in your file are expected to match. Here the generic name G is used: +/// +/// <table> +/// <tr> +/// <th> Suffix </th> +/// <th> Generated files </th> +/// </tr> +/// <tr> +/// <td> lexer grammar (G.g3l) </td> +/// <td> GLexer.c GLexer.h</td> +/// </tr> +/// <tr> +/// <td> parser grammar (G.g3p) </td> +/// <td> GParser.c GParser.h </td> +/// </tr> +/// <tr> +/// <td> grammar G (G.g3pl) </td> +/// <td> GParser.c GParser.h GLexer.c GLexer.h</td> +/// </tr> +/// <tr> +/// <td> tree grammar G; (G.g3t) </td> +/// <td> G.c G.h </td> +/// </tr> +/// </table> +/// +/// The generated .c files reference the .h files using <G.h>, so you must use <code>-I.</code> on your compiler command line +/// (or include the current directory in your include paths in Visual Studio). Additionally, the generated .h files reference +/// <code>antlr3.h</code>, so you must use <code>-I/path/to/antlr/include</code> (E.g. <code>-I /usr/local/include</code>) to reference the standard ANTLR include files. +/// +/// In order to reference the library file at compile time (you can/should only reference one) you need to use the +/// <code>-L/path/to/antlr/lib</code> (E.g. <code>-L /usr/local/lib</code>) on Unix, or add the path to your "Additional Library Path" in +/// Visual Studio. You also need to specify the library using <code>-L</code> on Unix (E.g. <code>-L /usr/local/lib -l antlr3c</code>) or add <code>antlr3c_dll.lib</code> +/// to your Additional Library Dependencies in Visual Studio. +/// +/// In case it isn't obvious, the generated files may be used to produce either a library or an executable (.EXE on Windows) file. +/// +/// If you use the shared version of the libraries, DLL or .so/.so/.a then you must ship the library with your +/// application must run in an environment whereby the library can be found by the runtime linker/loader. +/// This usually involves specifying the directory in which the library lives to an environment variable. +/// On Windows, X:{yourwininstalldir}\system32 will be searched automatically. +/// +/// \section invoke Invoking Your Generated Recognizer +/// +/// In order to run your lexer/parser/tree parser combination, you will need a small function (or main) +/// function that controls the sequence of events, from reading the input file or string, through to +/// invoking the tree parser(s) and retrieving the results. See "Using the ANTLR3C C Target" for more +/// detailed instructions, but if you just want to get going as fast as possible, study the following +/// code example. +/// +/// \code +/// +/// // You may adopt your own practices by all means, but in general it is best +/// // to create a single include for your project, that will include the ANTLR3 C +/// // runtime header files, the generated header files (all of which are safe to include +/// // multiple times) and your own project related header files. Use <> to include and +/// // -I on the compile line (which vs2005 now handles, where vs2003 did not). +/// // +/// #include <treeparser.h> +/// +/// // Main entry point for this example +/// // +/// int ANTLR3_CDECL +/// main (int argc, char *argv[]) +/// { +/// // Now we declare the ANTLR related local variables we need. +/// // Note that unless you are convinced you will never need thread safe +/// // versions for your project, then you should always create such things +/// // as instance variables for each invocation. +/// // ------------------- +/// +/// // Name of the input file. Note that we always use the abstract type pANTLR3_UINT8 +/// // for ASCII/8 bit strings - the runtime library guarantees that this will be +/// // good on all platforms. This is a general rule - always use the ANTLR3 supplied +/// // typedefs for pointers/types/etc. +/// // +/// pANTLR3_UINT8 fName; +/// +/// // The ANTLR3 character input stream, which abstracts the input source such that +/// // it is easy to privide inpput from different sources such as files, or +/// // memory strings. +/// // +/// // For an 8Bit/latin-1/etc memory string use: +/// // input = antlr3New8BitStringInPlaceStream (stringtouse, (ANTLR3_UINT32) length, NULL); +/// // +/// // For a UTF16 memory string use: +/// // input = antlr3NewUTF16StringInPlaceStream (stringtouse, (ANTLR3_UINT32) length, NULL); +/// // +/// // For input from a file, see code below +/// // +/// // Note that this is essentially a pointer to a structure containing pointers to functions. +/// // You can create your own input stream type (copy one of the existing ones) and override any +/// // individual function by installing your own pointer after you have created the standard +/// // version. +/// // +/// pANTLR3_INPUT_STREAM input; +/// +/// // The lexer is of course generated by ANTLR, and so the lexer type is not upper case. +/// // The lexer is supplied with a pANTLR3_INPUT_STREAM from whence it consumes its +/// // input and generates a token stream as output. This is the ctx (CTX macro) pointer +/// // for your lexer. +/// // +/// pLangLexer lxr; +/// +/// // The token stream is produced by the ANTLR3 generated lexer. Again it is a structure based +/// // API/Object, which you can customise and override methods of as you wish. a Token stream is +/// // supplied to the generated parser, and you can write your own token stream and pass this in +/// // if you wish. +/// // +/// pANTLR3_COMMON_TOKEN_STREAM tstream; +/// +/// // The Lang parser is also generated by ANTLR and accepts a token stream as explained +/// // above. The token stream can be any source in fact, so long as it implements the +/// // ANTLR3_TOKEN_SOURCE interface. In this case the parser does not return anything +/// // but it can of course specify any kind of return type from the rule you invoke +/// // when calling it. This is the ctx (CTX macro) pointer for your parser. +/// // +/// pLangParser psr; +/// +/// // The parser produces an AST, which is returned as a member of the return type of +/// // the starting rule (any rule can start first of course). This is a generated type +/// // based upon the rule we start with. +/// // +/// LangParser_decl_return langAST; +/// +/// +/// // The tree nodes are managed by a tree adaptor, which doles +/// // out the nodes upon request. You can make your own tree types and adaptors +/// // and override the built in versions. See runtime source for details and +/// // eventually the wiki entry for the C target. +/// // +/// pANTLR3_COMMON_TREE_NODE_STREAM nodes; +/// +/// // Finally, when the parser runs, it will produce an AST that can be traversed by the +/// // the tree parser: c.f. LangDumpDecl.g3t This is the ctx (CTX macro) pointer for your +/// // tree parser. +/// // +/// pLangDumpDecl treePsr; +/// +/// // Create the input stream based upon the argument supplied to us on the command line +/// // for this example, the input will always default to ./input if there is no explicit +/// // argument. +/// // +/// if (argc < 2 || argv[1] == NULL) +/// { +/// fName =(pANTLR3_UINT8)"./input"; // Note in VS2005 debug, working directory must be configured +/// } +/// else +/// { +/// fName = (pANTLR3_UINT8)argv[1]; +/// } +/// +/// // Create the input stream using the supplied file name +/// // (Use antlr38BitFileStreamNew for UTF16 input). +/// // +/// input = antlr38BitFileStreamNew(fName); +/// +/// // The input will be created successfully, providing that there is enough +/// // memory and the file exists etc +/// // +/// if ( input == NULL ) +/// { +/// ANTLR3_FPRINTF(stderr, "Unable to open file %s due to malloc() failure1\n", (char *)fName); +/// } +/// +/// // Our input stream is now open and all set to go, so we can create a new instance of our +/// // lexer and set the lexer input to our input stream: +/// // (file | memory | ?) --> inputstream -> lexer --> tokenstream --> parser ( --> treeparser )? +/// // +/// lxr = LangLexerNew(input); // CLexerNew is generated by ANTLR +/// +/// // Need to check for errors +/// // +/// if ( lxr == NULL ) +/// { +/// ANTLR3_FPRINTF(stderr, "Unable to create the lexer due to malloc() failure1\n"); +/// exit(ANTLR3_ERR_NOMEM); +/// } +/// +/// // Our lexer is in place, so we can create the token stream from it +/// // NB: Nothing happens yet other than the file has been read. We are just +/// // connecting all these things together and they will be invoked when we +/// // call the parser rule. ANTLR3_SIZE_HINT can be left at the default usually +/// // unless you have a very large token stream/input. Each generated lexer +/// // provides a token source interface, which is the second argument to the +/// // token stream creator. +/// // Note tha even if you implement your own token structure, it will always +/// // contain a standard common token within it and this is the pointer that +/// // you pass around to everything else. A common token as a pointer within +/// // it that should point to your own outer token structure. +/// // +/// tstream = antlr3CommonTokenStreamSourceNew(ANTLR3_SIZE_HINT, lxr->pLexer->tokSource); +/// +/// if (tstream == NULL) +/// { +/// ANTLR3_FPRINTF(stderr, "Out of memory trying to allocate token stream\n"); +/// exit(ANTLR3_ERR_NOMEM); +/// } +/// +/// // Finally, now that we have our lexer constructed, we can create the parser +/// // +/// psr = LangParserNew(tstream); // CParserNew is generated by ANTLR3 +/// +/// if (psr == NULL) +/// { +/// ANTLR3_FPRINTF(stderr, "Out of memory trying to allocate parser\n"); +/// exit(ANTLR3_ERR_NOMEM); +/// } +/// +/// // We are all ready to go. Though that looked complicated at first glance, +/// // I am sure, you will see that in fact most of the code above is dealing +/// // with errors and there isn;t really that much to do (isn;t this always the +/// // case in C? ;-). +/// // +/// // So, we now invoke the parser. All elements of ANTLR3 generated C components +/// // as well as the ANTLR C runtime library itself are pseudo objects. This means +/// // that they are represented as pointers to structures, which contain any +/// // instance data they need, and a set of pointers to other interfaces or +/// // 'methods'. Note that in general, these few pointers we have created here are +/// // the only things you will ever explicitly free() as everything else is created +/// // via factories, that allocate memory efficiently and free() everything they use +/// // automatically when you close the parser/lexer/etc. +/// // +/// // Note that this means only that the methods are always called via the object +/// // pointer and the first argument to any method, is a pointer to the structure itself. +/// // It also has the side advantage, if you are using an IDE such as VS2005 that can do it +/// // that when you type ->, you will see a list of all the methods the object supports. +/// // +/// langAST = psr->decl(psr); +/// +/// // If the parser ran correctly, we will have a tree to parse. In general I recommend +/// // keeping your own flags as part of the error trapping, but here is how you can +/// // work out if there were errors if you are using the generic error messages +/// // +/// if (psr->pParser->rec->errorCount > 0) +/// { +/// ANTLR3_FPRINTF(stderr, "The parser returned %d errors, tree walking aborted.\n", psr->pParser->rec->errorCount); +/// +/// } +/// else +/// { +/// nodes = antlr3CommonTreeNodeStreamNewTree(langAST.tree, ANTLR3_SIZE_HINT); // sIZE HINT WILL SOON BE DEPRECATED!! +/// +/// // Tree parsers are given a common tree node stream (or your override) +/// // +/// treePsr = LangDumpDeclNew(nodes); +/// +/// treePsr->decl(treePsr); +/// nodes ->free (nodes); nodes = NULL; +/// treePsr ->free (treePsr); treePsr = NULL; +/// } +/// +/// // We did not return anything from this parser rule, so we can finish. It only remains +/// // to close down our open objects, in the reverse order we created them +/// // +/// psr ->free (psr); psr = NULL; +/// tstream ->free (tstream); tstream = NULL; +/// lxr ->free (lxr); lxr = NULL; +/// input ->close (input); input = NULL; +/// +/// return 0; +/// } +/// \endcode +/// |