compile.c

jam源码

	 */

	if( nt )
	{
	    TARGET *t = bindtarget( nt->string );
	    SETTINGS *s = copysettings( t->settings );

	    pushsettings( s );
	    result = (*parse->right->func)( parse->right, args, jmp );
	    popsettings( s );
	    freesettings( s );
	}

	list_free( nt );

	return result;
}

/*
 * compile_rule() - compile a single user defined rule
 *
 *	parse->left	list of rules to run
 *	parse->right	parameters (list of lists) to rule, recursing left
 *
 * Wrapped around evaluate_rule() so that headers() can share it.
 */

LIST *
compile_rule(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	LOL	nargs[1];
	LIST	*result = 0;
	LIST	*ll, *l;
	PARSE	*p;

	/* list of rules to run -- normally 1! */

	ll = (*parse->left->func)( parse->left, args, jmp );

	/* Build up the list of arg lists */

	lol_init( nargs );

	for( p = parse->right; p; p = p->left )
	    lol_add( nargs, (*p->right->func)( p->right, args, jmp ) );

	/* Run rules, appending results from each */

	for( l = ll; l; l = list_next( l ) )
	    result = evaluate_rule( l->string, nargs, result );

	list_free( ll );
	lol_free( nargs );

	return result;
}

/*
 * evaluate_rule() - execute a rule invocation
 */

LIST *
evaluate_rule(
	const char *rulename,
	LOL	*args, 
	LIST	*result )
{
	RULE	*rule = bindrule( rulename );

	if( DEBUG_COMPILE )
	{
	    debug_compile( 1, rulename );
	    lol_print( args );
	    printf( "\n" );
	}

	/* Check traditional targets $(<) and sources $(>) */

	if( !rule->actions && !rule->procedure )
	    printf( "warning: unknown rule %s\n", rule->name );

	/* If this rule will be executed for updating the targets */
	/* then construct the action for make(). */

	if( rule->actions )
	{
	    TARGETS	*t;
	    ACTION	*action;

	    /* The action is associated with this instance of this rule */

	    action = (ACTION *)malloc( sizeof( ACTION ) );
	    memset( (char *)action, '\0', sizeof( *action ) );

	    action->rule = rule;
	    action->targets = targetlist( (TARGETS *)0, lol_get( args, 0 ) );
	    action->sources = targetlist( (TARGETS *)0, lol_get( args, 1 ) );

	    /* Append this action to the actions of each target */

	    for( t = action->targets; t; t = t->next )
		t->target->actions = actionlist( t->target->actions, action );
	}

	/* Now recursively compile any parse tree associated with this rule */

	if( rule->procedure )
	{
	    PARSE *parse = rule->procedure;
	    SETTINGS *s = 0;
	    int jmp = JMP_NONE;
	    LIST *l;
	    int i;

	    /* build parameters as local vars */

	    for( l = rule->params, i = 0; l; l = l->next, i++ )
		s = addsettings( s, 0, l->string, 
		    list_copy( L0, lol_get( args, i ) ) );

	    /* Run rule. */
	    /* Bring in local params. */
	    /* refer/free to ensure rule not freed during use. */

	    parse_refer( parse );

	    pushsettings( s );
	    result = list_append( result, (*parse->func)( parse, args, &jmp ) );
	    popsettings( s );
	    freesettings( s );

	    parse_free( parse );
	}

	if( DEBUG_COMPILE )
	    debug_compile( -1, 0 );

	return result;
}

/*
 * compile_rules() - compile a chain of rules
 *
 *	parse->left	single rule
 *	parse->right	more compile_rules() by right-recursion
 */

LIST *
compile_rules(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	/* Ignore result from first statement; return the 2nd. */
	/* Optimize recursion on the right by looping. */

	LIST 	*result = 0;

	while( *jmp == JMP_NONE && parse->func == compile_rules )
	{
	    list_free( result );
	    result = (*parse->left->func)( parse->left, args, jmp );
	    parse = parse->right;
	}

	if( *jmp == JMP_NONE )
	{
	    list_free( result );
	    result = (*parse->func)( parse, args, jmp );
	}

	return result;
}

/*
 * compile_set() - compile the "set variable" statement
 *
 *	parse->left	variable names
 *	parse->right	variable values 
 *	parse->num	VAR_SET/APPEND/DEFAULT
 */

LIST *
compile_set(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	LIST	*nt = (*parse->left->func)( parse->left, args, jmp );
	LIST	*ns = (*parse->right->func)( parse->right, args, jmp );
	LIST	*l;

	if( DEBUG_COMPILE )
	{
	    debug_compile( 0, "set" );
	    list_print( nt );
	    printf( " %s ", set_names[ parse->num ] );
	    list_print( ns );
	    printf( "\n" );
	}

	/* Call var_set to set variable */
	/* var_set keeps ns, so need to copy it */

	for( l = nt; l; l = list_next( l ) )
	    var_set( l->string, list_copy( L0, ns ), parse->num );

	list_free( nt );

	return ns;
}

/*
 * compile_setcomp() - support for `rule` - save parse tree 
 *
 *	parse->string	rule name
 *	parse->left	list of argument names
 *	parse->right	rules for rule
 */

LIST *
compile_setcomp(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	RULE	*rule = bindrule( parse->string );
	LIST	*params = 0;
	PARSE	*p;

	/* Build param list */

	for( p = parse->left; p; p = p->left )
	    params = list_new( params, p->string, 1 );

	if( DEBUG_COMPILE )
	{
	    debug_compile( 0, "rule" );
	    printf( "%s ", parse->string );
	    list_print( params );
	    printf( "\n" );
	}

	/* Free old one, if present */

	if( rule->procedure )
	    parse_free( rule->procedure );

	if( rule->params )
	    list_free( rule->params );

	rule->procedure = parse->right;
	rule->params = params;

	/* we now own this parse tree */
	/* don't let parse_free() release it */

	parse_refer( parse->right );

	return L0;
}

/*
 * compile_setexec() - support for `actions` - save execution string 
 *
 *	parse->string	rule name
 *	parse->string1	OS command string
 *	parse->num	flags
 *	parse->left	`bind` variables
 *
 * Note that the parse flags (as defined in compile.h) are transfered
 * directly to the rule flags (as defined in rules.h).
 */

LIST *
compile_setexec(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	RULE	*rule = bindrule( parse->string );
	LIST	*bindlist = (*parse->left->func)( parse->left, args, jmp );
	
	/* Free old one, if present */

	if( rule->actions )
	{
	    freestr( rule->actions );
	    list_free( rule->bindlist );
	}

	rule->actions = copystr( parse->string1 );
	rule->bindlist = bindlist;
	rule->flags = parse->num;

	return L0;
}

/*
 * compile_settings() - compile the "on =" (set variable on exec) statement
 *
 *	parse->left	variable names
 *	parse->right	target name 
 *	parse->third	variable value 
 *	parse->num	VAR_SET/APPEND/DEFAULT
 */

LIST *
compile_settings(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	LIST	*nt = (*parse->left->func)( parse->left, args, jmp );
	LIST	*ns = (*parse->third->func)( parse->third, args, jmp );
	LIST	*targets = (*parse->right->func)( parse->right, args, jmp );
	LIST	*ts;

	if( DEBUG_COMPILE )
	{
	    debug_compile( 0, "set" );
	    list_print( nt );
	    printf( "on " );
	    list_print( targets );
	    printf( " %s ", set_names[ parse->num ] );
	    list_print( ns );
	    printf( "\n" );
	}

	/* Call addsettings to save variable setting */
	/* addsettings keeps ns, so need to copy it */
	/* Pass append flag to addsettings() */

	for( ts = targets; ts; ts = list_next( ts ) )
	{
	    TARGET 	*t = bindtarget( ts->string );
	    LIST	*l;

	    for( l = nt; l; l = list_next( l ) )
		t->settings = addsettings( t->settings, parse->num,
				l->string, list_copy( (LIST*)0, ns ) );
	}

	list_free( nt );
	list_free( targets );

	return ns;
}

/*
 * compile_switch() - compile 'switch' rule
 *
 *	parse->left	switch value (only 1st used)
 *	parse->right	cases
 *
 *	cases->left	1st case
 *	cases->right	next cases
 *
 *	case->string	argument to match
 *	case->left	parse tree to execute
 */

LIST *
compile_switch(
	PARSE	*parse,
	LOL	*args,
	int	*jmp )
{
	LIST	*nt = (*parse->left->func)( parse->left, args, jmp );
	LIST	*result = 0;

	if( DEBUG_COMPILE )
	{
	    debug_compile( 0, "switch" );
	    list_print( nt );
	    printf( "\n" );
	}

	/* Step through cases */

	for( parse = parse->right; parse; parse = parse->right )
	{
	    if( !glob( parse->left->string, nt ? nt->string : "" ) )
	    {
		/* Get & exec parse tree for this case */
		parse = parse->left->left;
		result = (*parse->func)( parse, args, jmp );
		break;
	    }
	}

	list_free( nt );

	return result;
}

/*
 * compile_while() - compile 'while' rule
 *
 *	parse->left		condition tree
 *	parse->right		execution tree
 */

LIST *
compile_while(
	PARSE	*p,
	LOL	*args,
	int	*jmp )
{
	LIST *result = 0;
	LIST *l;

	/* Returns the value from the last execution of the block */

	while( ( *jmp == JMP_NONE ) && 
	       ( l = (*p->left->func)( p->left, args, jmp ) ) )
	{
	    /* Always toss while's expression */

	    list_free( l );

	    /* Keep only last result. */

	    list_free( result );
	    result = (*p->right->func)( p->right, args, jmp );

	    /* continue loop? */

	    if( *jmp == JMP_CONTINUE )
		*jmp = JMP_NONE;
	}

	/* Here by break/continue? */

	if( *jmp == JMP_BREAK || *jmp == JMP_CONTINUE )
	    *jmp = JMP_NONE;

	/* Returns result of last loop */

	return result;
}

/*
 * debug_compile() - printf with indent to show rule expansion.
 */

static void
debug_compile( int which, const char *s )
{
	static int level = 0;
	static char indent[36] = ">>>>|>>>>|>>>>|>>>>|>>>>|>>>>|>>>>|";
	int i = ((1+level) * 2) % 35;

	if( which >= 0 )
	    printf( "%*.*s ", i, i, indent );

	if( s )
	    printf( "%s ", s );

	level += which;
}