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/*

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 * (c) 2003 Mario de Sousa

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 *

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 * Offered to the public under the terms of the GNU General Public License

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 * as published by the Free Software Foundation; either version 2 of the

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 * License, or (at your option) any later version.

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 *

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 * This program is distributed in the hope that it will be useful, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

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 * Public License for more details.

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 *

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 * This code is made available on the understanding that it will not be

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 * used in safety-critical situations without a full and competent review.

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 */

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/*

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 * An IEC 61131-3 IL and ST compiler.

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 *

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 * Based on the

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 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

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 *

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 */

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/*

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 ****************************************************************

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 ****************************************************************

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 ****************************************************************

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 *********                                              *********

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 *********                                              *********

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 *********   O V E R A L L    A R C H I T E C T U R E   *********

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 *********                                              *********

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 *********                                              *********

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 ****************************************************************

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 ****************************************************************

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 ****************************************************************

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 The compiler works in 4(+1) stages:

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 Stage 1   - Lexical analyser      - implemented with flex (iec.flex)

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 Stage 2   - Syntax parser         - implemented with bison (iec.y)

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 Stage 3   - Semantics analyser    - not yet implemented

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 Stage 4   - Code generator        - implemented in C++

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 Stage 4+1 - Binary code generator - gcc, javac, etc...

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 Data structures passed between stages, in global variables:

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 1->2   : tokens (int), and token values (char *)

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 2->1   : symbol tables (defined in symtable.hh)

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 2->3   : abstract syntax tree (tree of C++ classes, in absyntax.hh file)

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 3->4   : Same as 2->3

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 4->4+1 : file with program in c, java, etc...

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 The compiler works in several passes:

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 Pass 1: executes stages 1 and 2 simultaneously

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 Pass 2: executes stage 3

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 Pass 3: executes stage 4

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 Pass 4: executes stage 4+1

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*/

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//#include <stdio.h>   // printf()

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#include <stdlib.h>  // EXIT_FAILURE

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#include "absyntax/absyntax.hh"  // symbol_c type

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/* A macro for printing out internal parser errors... */

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#include <iostream> // required for std::cerr

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#define ERROR error_exit(__FILE__,__LINE__)

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void error_exit(const char *file_name, int line_no) {

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  std::cerr << "\nInternal program error in file " << file_name

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            << " at line " << line_no << "\n\n\n";

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  exit(EXIT_FAILURE);

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}

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/* forward declarations... */

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int stage1_2(const char *filename, const char *includedir, symbol_c **tree_root);

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//int stage3(symbol_c *tree_root);

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int stage4(symbol_c *tree_root, const char *builddir);

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static void printusage(const char *cmd) {

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  printf("%s [<input_file>] [-I <include_directory>] [<target_directory>]\n", cmd);

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}

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int main(int argc, char **argv) {

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  symbol_c *tree_root;

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  char * includedir = NULL;

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  char * builddir = NULL;

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  if (argc == 5) {

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    builddir = argv[4];

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    argc = 4;

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  }

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  if (argc == 4) {

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    if (strcmp(argv[2], "-I") != 0) {

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      printusage(argv[0]);

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      return EXIT_FAILURE;

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    }

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    includedir = argv[3];

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    argc = 2;

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  }

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  if (argc == 3) {

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    builddir = argv[2];

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    argc = 2;

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  }    

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  if (argc != 2) {

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    printusage(argv[0]);

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    return EXIT_FAILURE;

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  }

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  /* 1st Pass */

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  if (stage1_2(argv[1], includedir, &tree_root) < 0)

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    return EXIT_FAILURE;

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  /* 2nd Pass */

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  /* not yet implemented... */

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  /*

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  if (stage3(tree_root) < 0)

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    return EXIT_FAILURE;

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  */

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  /* 3rd Pass */

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  if (stage4(tree_root, builddir) < 0)

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    return EXIT_FAILURE;

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  /* 4th Pass */

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  /* Currently implemented in the Makefile! */

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  return 0;

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}

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