/* $XConsortium: parse.c /main/33 1996/12/04 10:11:28 swick $ */
/*

Copyright (c) 1993, 1994  X Consortium

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of the X Consortium shall not be
used in advertising or otherwise to promote the sale, use or other dealings
in this Software without prior written authorization from the X Consortium.

*/

#include "def.h"

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

#if __STDC__
static int gobble(   struct filepointer *filep, 
                     struct inclist *file, 
                     struct inclist *file_red);
static int deftype(  char   *line,
                     struct filepointer *filep,
                     struct inclist *file_red, 
                     struct inclist *file,
                     int   parse_it);
static struct symtab **fdefined( char   *symbol,
                                 struct inclist   *file,
                                 struct inclist   **srcfile);
static int zero_value(  char   *exp,
                        struct filepointer *filep,
                        struct inclist *file_red);

static struct symtab **slookup( char *symbol, struct inclist *file);

static int merge2defines( struct inclist *file1, struct inclist *file2);
static void undefine( char *symbol, struct inclist *file);
static int match(char *str, char **list); 
static void add_include(struct filepointer *filep,
                        struct inclist	*file, 
                        struct inclist *file_red,
                        char *include,
                        boolean dot,
                        int failOK);
#else
static int gobble();
static int deftype();
static struct symtab **fdefined();
static int zero_value();
static struct symtab **slookup();
static int merge2defines();
static void undefine();
static int match(); 
static void add_include();
#endif


/*-------------------------------------------------------------------------*/
static 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:
         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.
----------------------------------------------------------------------------*/
static 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);
}

/*-------------------------------------------------------------------------*/
static 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
----------------------------------------------------------------------------*/
static 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);
}

/*-------------------------------------------------------------------------*/
static 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);
}

/*-------------------------------------------------------------------------*/
static 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;
}

/*-------------------------------------------------------------------------*/
static 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:
         if (!local_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);
}

/*-------------------------------------------------------------------------*/
static int match(str, list)
   register char   *str, **list;
{
   register int   i;

   for (i=0; *list; i++, list++)
      if (strcmp(str, *list) == 0)
         return(i);
   return(-1);
}

/*-------------------------------------------------------------------------*/
static void add_include(filep, file, file_red, include, dot, failOK)
	struct filepointer	*filep;
	struct inclist	*file, *file_red;
	char	*include;
	boolean	dot;
   int failOK;
{
	register struct inclist	*newfile;
	register struct filepointer	*content;

	/*
	 * First decide what the pathname of this include file really is.
	 */
	newfile = inc_path(file->i_file, include, dot);
	if (newfile == NULL) {
		if (failOK)
		    return;
		if (file != file_red)
			warning("%s (reading %s, line %d): ",
				file_red->i_file, file->i_file, filep->f_line);
		else
			warning("%s, line %d: ", file->i_file, filep->f_line);
		warning1("cannot find include file \"%s\"\n", include);
		show_where_not = TRUE;
		newfile = inc_path(file->i_file, include, dot);
		show_where_not = FALSE;
	}

	if (newfile) {
		included_by(file, newfile);
		if (!(newfile->i_flags & SEARCHED)) {
			newfile->i_flags |= SEARCHED;
			content = getfile(newfile->i_file);
			find_includes(content, newfile, file_red, 0, failOK);
			freefile(content);
		}
	}
}

