/* $TOG: parse.c /main/35 1998/03/25 08:17:55 kaleb $ */
/*

@OPENGROUP_COPYRIGHT@
COPYRIGHT NOTICE
Copyright (c) 1990, 1991, 1992, 1993 Open Software Foundation, Inc.
Copyright (c) 1996, 1997, 1998, 1999, 2000 The Open Group
ALL RIGHTS RESERVED (MOTIF). See the file named COPYRIGHT.MOTIF for
the full copyright text.
 
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

This software is subject to an open license. It may only be
used on, with or for operating systems which are themselves open
source systems. You must contact The Open Group for a license
allowing distribution and sublicensing of this software on, with,
or for operating systems which are not Open Source programs.

See http://www.opengroup.org/openmotif/license for full
details of the license agreement. Any use, reproduction, or
distribution of the program constitutes recipient's acceptance of
this agreement.

EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, THE PROGRAM IS
PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT LIMITATION, ANY
WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY
OR FITNESS FOR A PARTICULAR PURPOSE

EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, NEITHER RECIPIENT
NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED
AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OR DISTRIBUTION OF THE PROGRAM OR THE
EXERCISE OF ANY RIGHTS GRANTED HEREUNDER, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.

*/

#include "def.h"

extern char	*directives[];
extern struct inclist	maininclist;

int
gobble(filep, file, file_red)
	register struct filepointer *filep;
	struct inclist		*file, *file_red;
{
	register char	*line;
	register int	type;

	while (line = getline(filep)) {
		switch(type = deftype(line, filep, file_red, file, FALSE)) {
		case IF:
		case IFFALSE:
		case IFGUESSFALSE:
		case IFDEF:
		case IFNDEF:
			type = gobble(filep, file, file_red);
			while ((type == ELIF) || (type == ELIFFALSE) ||
			       (type == ELIFGUESSFALSE))
			    type = gobble(filep, file, file_red);
			if (type == ELSE)
			        (void)gobble(filep, file, file_red);
			break;
		case ELSE:
		case ENDIF:
			debug(0,("%s, line %d: #%s\n",
				file->i_file, filep->f_line,
				directives[type]));
			return(type);
		case DEFINE:
		case UNDEF:
		case INCLUDE:
		case INCLUDEDOT:
		case PRAGMA:
		case ERROR:
		case IDENT:
		case SCCS:
		case EJECT:
		case WARNING:
			break;
		case ELIF:
		case ELIFFALSE:
		case ELIFGUESSFALSE:
			return(type);
		case -1:
			warning("%s, line %d: unknown directive == \"%s\"\n",
				file_red->i_file, filep->f_line, line);
			break;
		}
	}
	return(-1);
}

/*
 * Decide what type of # directive this line is.
 */
int deftype (line, filep, file_red, file, parse_it)
	register char	*line;
	register struct filepointer *filep;
	register struct inclist *file_red, *file;
	int	parse_it;
{
	register char	*p;
	char	*directive, savechar;
	register int	ret;

	/*
	 * Parse the directive...
	 */
	directive=line+1;
	while (*directive == ' ' || *directive == '\t')
		directive++;

	p = directive;
	while (*p >= 'a' && *p <= 'z')
		p++;
	savechar = *p;
	*p = '\0';
	ret = match(directive, directives);
	*p = savechar;

	/* If we don't recognize this compiler directive or we happen to just
	 * be gobbling up text while waiting for an #endif or #elif or #else
	 * in the case of an #elif we must check the zero_value and return an
	 * ELIF or an ELIFFALSE.
	 */

	if (ret == ELIF && !parse_it)
	{
	    while (*p == ' ' || *p == '\t')
		p++;
	    /*
	     * parse an expression.
	     */
	    debug(0,("%s, line %d: #elif %s ",
		   file->i_file, filep->f_line, p));
	    ret = zero_value(p, filep, file_red);
	    if (ret != IF)
	    {
		debug(0,("false...\n"));
		if (ret == IFFALSE)
		    return(ELIFFALSE);
		else
		    return(ELIFGUESSFALSE);
	    }
	    else
	    {
		debug(0,("true...\n"));
		return(ELIF);
	    }
	}

	if (ret < 0 || ! parse_it)
		return(ret);

	/*
	 * now decide how to parse the directive, and do it.
	 */
	while (*p == ' ' || *p == '\t')
		p++;
	switch (ret) {
	case IF:
		/*
		 * parse an expression.
		 */
		ret = zero_value(p, filep, file_red);
		debug(0,("%s, line %d: %s #if %s\n",
			 file->i_file, filep->f_line, ret?"false":"true", p));
		break;
	case IFDEF:
	case IFNDEF:
		debug(0,("%s, line %d: #%s %s\n",
			file->i_file, filep->f_line, directives[ret], p));
	case UNDEF:
		/*
		 * separate the name of a single symbol.
		 */
		while (isalnum(*p) || *p == '_')
			*line++ = *p++;
		*line = '\0';
		break;
	case INCLUDE:
		debug(2,("%s, line %d: #include %s\n",
			file->i_file, filep->f_line, p));

		/* Support ANSI macro substitution */
		{
		    struct symtab **sym = isdefined(p, file_red, NULL);
		    while (sym) {
			p = (*sym)->s_value;
			debug(3,("%s : #includes SYMBOL %s = %s\n",
			       file->i_incstring,
			       (*sym) -> s_name,
			       (*sym) -> s_value));
			/* mark file as having included a 'soft include' */
			file->i_flags |= INCLUDED_SYM; 
			sym = isdefined(p, file_red, NULL);
		    }
		}

		/*
		 * Separate the name of the include file.
		 */
		while (*p && *p != '"' && *p != '<')
			p++;
		if (! *p)
			return(-2);
		if (*p++ == '"') {
			ret = INCLUDEDOT;
			while (*p && *p != '"')
				*line++ = *p++;
		} else
			while (*p && *p != '>')
				*line++ = *p++;
		*line = '\0';
		break;
	case DEFINE:
		/*
		 * copy the definition back to the beginning of the line.
		 */
		strcpy (line, p);
		break;
	case ELSE:
	case ENDIF:
	case ELIF:
	case PRAGMA:
	case ERROR:
	case IDENT:
	case SCCS:
	case EJECT:
		debug(0,("%s, line %d: #%s\n",
			file->i_file, filep->f_line, directives[ret]));
		/*
		 * nothing to do.
		 */
		break;
	}
	return(ret);
}

struct symtab **fdefined(symbol, file, srcfile)
	register char	*symbol;
	struct inclist	*file;
	struct inclist	**srcfile;
{
	register struct inclist	**ip;
	register struct symtab	**val;
	register int	i;
	static int	recurse_lvl = 0;

	if (file->i_flags & DEFCHECKED)
		return(NULL);
	file->i_flags |= DEFCHECKED;
	if (val = slookup(symbol, file))
		debug(1,("%s defined in %s as %s\n",
			 symbol, file->i_file, (*val)->s_value));
	if (val == NULL && file->i_list)
		{
		for (ip = file->i_list, i=0; i < file->i_listlen; i++, ip++)
			if (file->i_merged[i]==FALSE) {
				val = fdefined(symbol, *ip, srcfile);
				if ((*ip)->i_flags & FINISHED) {
					merge2defines(file,*ip);
					file->i_merged[i]=TRUE;
				    }
				if (val!=NULL) break;
			}
		}
	else if (val != NULL && srcfile != NULL) *srcfile = file;
	recurse_lvl--;
	file->i_flags &= ~DEFCHECKED;

	return(val);
}

struct symtab **isdefined(symbol, file, srcfile)
	register char	*symbol;
	struct inclist	*file;
	struct inclist	**srcfile;
{
	register struct symtab	**val;

	if (val = slookup(symbol, &maininclist)) {
		debug(1,("%s defined on command line\n", symbol));
		if (srcfile != NULL) *srcfile = &maininclist;
		return(val);
	}
	if (val = fdefined(symbol, file, srcfile))
		return(val);
	debug(1,("%s not defined in %s\n", symbol, file->i_file));
	return(NULL);
}

/*
 * Return type based on if the #if expression evaluates to 0
 */
int
zero_value(exp, filep, file_red)
	register char	*exp;
	register struct filepointer *filep;
	register struct inclist *file_red;
{
	if (cppsetup(exp, filep, file_red))
	    return(IFFALSE);
	else
	    return(IF);
}

void
define2(name, val, file)
	char	*name, *val;
	struct inclist	*file;
{
    int first, last, below;
    register struct symtab **sp = NULL, **dest;
    struct symtab *stab;

    /* Make space if it's needed */
    if (file->i_defs == NULL)
    {
	file->i_defs = (struct symtab **)
			malloc(sizeof (struct symtab*) * SYMTABINC);
	file->i_ndefs = 0;
    }
    else if (!(file->i_ndefs % SYMTABINC))
	file->i_defs = (struct symtab **)
			realloc(file->i_defs,
			   sizeof(struct symtab*)*(file->i_ndefs+SYMTABINC));

    if (file->i_defs == NULL)
	fatalerr("malloc()/realloc() failure in insert_defn()\n");

    below = first = 0;
    last = file->i_ndefs - 1;
    while (last >= first)
    {
	/* Fast inline binary search */
	register char *s1;
	register char *s2;
	register int middle = (first + last) / 2;

	/* Fast inline strchr() */
	s1 = name;
	s2 = file->i_defs[middle]->s_name;
	while (*s1++ == *s2++)
	    if (s2[-1] == '\0') break;

	/* If exact match, set sp and break */
	if (*--s1 == *--s2) 
	{
	    sp = file->i_defs + middle;
	    break;
	}

	/* If name > i_defs[middle] ... */
	if (*s1 > *s2) 
	{
	    below = first;
	    first = middle + 1;
	}
	/* else ... */
	else
	{
	    below = last = middle - 1;
	}
    }

    /* Search is done.  If we found an exact match to the symbol name,
       just replace its s_value */
    if (sp != NULL)
    {
	free((*sp)->s_value);
	(*sp)->s_value = copy(val);
	return;
    }

    sp = file->i_defs + file->i_ndefs++;
    dest = file->i_defs + below + 1;
    while (sp > dest)
    {
	*sp = sp[-1];
	sp--;
    }
    stab = (struct symtab *) malloc(sizeof (struct symtab));
    if (stab == NULL)
	fatalerr("malloc()/realloc() failure in insert_defn()\n");

    stab->s_name = copy(name);
    stab->s_value = copy(val);
    *sp = stab;
}

void
define(def, file)
	char	*def;
	struct inclist	*file;
{
    char *val;

    /* Separate symbol name and its value */
    val = def;
    while (isalnum(*val) || *val == '_')
	val++;
    if (*val)
	*val++ = '\0';
    while (*val == ' ' || *val == '\t')
	val++;

    if (!*val)
	val = "1";
    define2(def, val, file);
}

struct symtab **slookup(symbol, file)
	register char	*symbol;
	register struct inclist	*file;
{
	register int first = 0;
	register int last = file->i_ndefs - 1;

	if (file) while (last >= first)
	{
	    /* Fast inline binary search */
	    register char *s1;
	    register char *s2;
	    register int middle = (first + last) / 2;

	    /* Fast inline strchr() */
	    s1 = symbol;
	    s2 = file->i_defs[middle]->s_name;
	    while (*s1++ == *s2++)
	        if (s2[-1] == '\0') break;

	    /* If exact match, we're done */
	    if (*--s1 == *--s2) 
	    {
	        return file->i_defs + middle;
	    }

	    /* If symbol > i_defs[middle] ... */
	    if (*s1 > *s2) 
	    {
	        first = middle + 1;
	    }
	    /* else ... */
	    else
	    {
	        last = middle - 1;
	    }
	}
	return(NULL);
}

int merge2defines(file1, file2)
	struct inclist	*file1;
	struct inclist	*file2;
{
	if ((file1!=NULL) && (file2!=NULL)) 
        {
		int first1 = 0;
		int last1 = file1->i_ndefs - 1;

		int first2 = 0;
		int last2 = file2->i_ndefs - 1;

                int first=0;
                struct symtab** i_defs = NULL;
		int deflen=file1->i_ndefs+file2->i_ndefs;

                if (deflen>0)
                { 
                	/* make sure deflen % SYMTABINC == 0 is still true */
                	deflen += (SYMTABINC - deflen % SYMTABINC) % SYMTABINC;
                	i_defs=(struct symtab**)
			    malloc(deflen*sizeof(struct symtab*));
                	if (i_defs==NULL) return 0;
        	}

        	while ((last1 >= first1) && (last2 >= first2))
        	{
	    		char *s1=file1->i_defs[first1]->s_name;
	    		char *s2=file2->i_defs[first2]->s_name;

     			if (strcmp(s1,s2) < 0)
                        	i_defs[first++]=file1->i_defs[first1++];
     			else if (strcmp(s1,s2) > 0)
                        	i_defs[first++]=file2->i_defs[first2++];
                        else /* equal */
                        {
                        	i_defs[first++]=file2->i_defs[first2++];
                                first1++;
                        }
        	}
        	while (last1 >= first1)
        	{
                        i_defs[first++]=file1->i_defs[first1++];
        	}
        	while (last2 >= first2)
        	{
                        i_defs[first++]=file2->i_defs[first2++];
        	}

                if (file1->i_defs) free(file1->i_defs);
                file1->i_defs=i_defs;
                file1->i_ndefs=first;
                
		return 1;
  	}
	return 0;
}

void
undefine(symbol, file)
	char	*symbol;
	register struct inclist	*file;
{
	register struct symtab **ptr;
	struct inclist *srcfile;
	while ((ptr = isdefined(symbol, file, &srcfile)) != NULL)
	{
	    srcfile->i_ndefs--;
	    for (; ptr < srcfile->i_defs + srcfile->i_ndefs; ptr++)
		*ptr = ptr[1];
	}
}

int
find_includes(filep, file, file_red, recursion, failOK)
	struct filepointer	*filep;
	struct inclist		*file, *file_red;
	int			recursion;
	boolean			failOK;
{
	register char	*line;
	register int	type;
	boolean recfailOK;

	while (line = getline(filep)) {
		switch(type = deftype(line, filep, file_red, file, TRUE)) {
		case IF:
		doif:
			type = find_includes(filep, file,
				file_red, recursion+1, failOK);
			while ((type == ELIF) || (type == ELIFFALSE) ||
			       (type == ELIFGUESSFALSE))
				type = gobble(filep, file, file_red);
			if (type == ELSE)
				gobble(filep, file, file_red);
			break;
		case IFFALSE:
		case IFGUESSFALSE:
		    doiffalse:
			if (type == IFGUESSFALSE || type == ELIFGUESSFALSE)
			    recfailOK = TRUE;
			else
			    recfailOK = failOK;
			type = gobble(filep, file, file_red);
			if (type == ELSE)
			    find_includes(filep, file,
					  file_red, recursion+1, recfailOK);
			else
			if (type == ELIF)
			    goto doif;
			else
			if ((type == ELIFFALSE) || (type == ELIFGUESSFALSE))
			    goto doiffalse;
			break;
		case IFDEF:
		case IFNDEF:
			if ((type == IFDEF && isdefined(line, file_red, NULL))
			 || (type == IFNDEF && !isdefined(line, file_red, NULL))) {
				debug(1,(type == IFNDEF ?
				    "line %d: %s !def'd in %s via %s%s\n" : "",
				    filep->f_line, line,
				    file->i_file, file_red->i_file, ": doit"));
				type = find_includes(filep, file,
					file_red, recursion+1, failOK);
				while (type == ELIF || type == ELIFFALSE || type == ELIFGUESSFALSE)
					type = gobble(filep, file, file_red);
				if (type == ELSE)
					gobble(filep, file, file_red);
			}
			else {
				debug(1,(type == IFDEF ?
				    "line %d: %s !def'd in %s via %s%s\n" : "",
				    filep->f_line, line,
				    file->i_file, file_red->i_file, ": gobble"));
				type = gobble(filep, file, file_red);
				if (type == ELSE)
					find_includes(filep, file,
						file_red, recursion+1, failOK);
				else if (type == ELIF)
				    	goto doif;
				else if (type == ELIFFALSE || type == ELIFGUESSFALSE)
				    	goto doiffalse;
			}
			break;
		case ELSE:
		case ELIFFALSE:
		case ELIFGUESSFALSE:
		case ELIF:
			if (!recursion)
				gobble(filep, file, file_red);
		case ENDIF:
			if (recursion)
				return(type);
		case DEFINE:
			define(line, file);
			break;
		case UNDEF:
			if (!*line) {
			    warning("%s, line %d: incomplete undef == \"%s\"\n",
				file_red->i_file, filep->f_line, line);
			    break;
			}
			undefine(line, file_red);
			break;
		case INCLUDE:
			add_include(filep, file, file_red, line, FALSE, failOK);
			break;
		case INCLUDEDOT:
			add_include(filep, file, file_red, line, TRUE, failOK);
			break;
		case ERROR:
		    	warning("%s: %d: %s\n", file_red->i_file,
				 filep->f_line, line);
		    	break;
		    
		case PRAGMA:
		case IDENT:
		case SCCS:
		case EJECT:
			break;
		case -1:
			warning("%s", file_red->i_file);
			if (file_red != file)
			    warning1(" (reading %s)", file->i_file);
			warning1(", line %d: unknown directive == \"%s\"\n",
				 filep->f_line, line);
			break;
		case -2:
			warning("%s", file_red->i_file);
			if (file_red != file)
			    warning1(" (reading %s)", file->i_file);
			warning1(", line %d: incomplete include == \"%s\"\n",
				 filep->f_line, line);
			break;
		}
	}
	file->i_flags |= FINISHED;
	return(-1);
}