/*
** MakefileData.h
**
** 	Types & functions related to the makefile data structure.
**
**	Written by Peter Sutton
**	April 2009
*/

#ifndef MAKEFILEDATA_H
#define MAKEFILEDATA_H

/* Definition structure - stores details of definition lines NAME = VALUE */
typedef struct {
    char* name;		
    char* value;
} Definition;

/* Rule structure - stores the arguments in a dependency rule. Note that
** argv[argc] will always be NULL, so that the argv array is suitable for
** passing to execvp. */
typedef struct {
    int argc;
    char** argv;
} Rule;

/* Target structure - stores the name of the file, and what it depends on
** and the rules to be executed to bring it up to date. Each target will have
** 0 or more dependencies and 1 or more rules. Dependencies will be unique. */
typedef struct {
    char* fileName;
    int numDependencies;
    char** dependencies; 
    int numRules;
    Rule* rules;
} Target;

/* Toplevel structure */
/* Note that there will be at least one target, and that targets[0] is the 
** first target listed in the file. There may be 0 or more definitions. */
typedef struct {
    int numDefinitions;
    Definition* definitions;
    int numTargets;
    Target* targets;
} MakefileData;


/****************************** FUNCTIONS ************************************/

    /* parse_file()
    **
    ** Read the contents of the given open file and return
    ** a structure representing our makefile. (Memory is allocated
    ** within the function for the Makefile structure and its elements.
    ** This memory can be deallocated using the free_makefile_data() 
    ** function.) If an error occurs, will print an error message to
    ** standard error and exit with an appropriate exit status.
    */
MakefileData* parse_file(FILE* fileHandle);

    /*  free_makefile_data()
    **
    ** Free the Makefile structure pointed to by makefilePtr 
    */
void free_makefile_data(MakefileData* makefilePtr);

    /*  print_makefile()
    **
    ** Print the Makefile structure pointed to by makefilePtr 
    */
void print_makefile_data(MakefileData* makefilePtr);

    /* find_target()
    **
    ** Find the given target in the makefile data structure (or a null
    ** pointer if it is not found)
    */
Target* find_target(MakefileData* makefilePtr, char* targetName);

    /* find_definition()
    **
    ** Find the given definition value in the makefile data structure (or
    ** a null pointer if it is not found)
    */
char* find_definition(MakefileData* makefilePtr, char* defName);

#endif