/* $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.

 */
/* $XFree86: xc/config/makedepend/parse.c,v 1.3 1997/01/12 10:39:45 dawes Exp $ */

#include "def.h"
#include <ctype.h>
#include <string.h>
#include <stdlib.h>

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

int gobble (struct filepointer *filep, struct inclist *file, struct inclist *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 (char *line, struct filepointer *filep, struct inclist *file_red,
             struct inclist *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 = (char *)(*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:
        case WARNING:
            debug (0, ("%s, line %d: #%s\n",
                       file->i_file, filep->f_line, directives[ret]));
            /* nothing to do. */
            break;
    }
    return (ret);
}

struct symtab **fdefined (const 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 (const 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 (char *exp, struct filepointer *filep, struct inclist *file_red)
{
    if (cppsetup (exp, filep, file_red))
        return (IFFALSE);
    else
        return (IF);
}

void define2 (const char *name, const char *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 const char *s1;
        register const 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 ((void *)(*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 (char *def, struct inclist *file)
{
    char *val;
    char *eol;

    /* Separate symbol name and its value */
    val = def;
    while (isalnum (*val) || *val == '_')
        val++;
    if (*val)
        *val++ = '\0';
    while (*val == ' ' || *val == '\t')
        val++;
    eol = strchr (val, 0);
    while (eol >= val && isspace (eol [-1]))
        eol--;

    if (eol <= val)
        val = (char *)"1";
    else
        *eol = 0;

    define2 (def, val, file);
}

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

    if (file)
        while (last >= first)
        {
            /* Fast inline binary search */
            register const char *s1;
            register const 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 (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))
        {
            const char *s1 = file1->i_defs[first1]->s_name;
            const 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 (const char *symbol, 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];
    }
}

static void display_included (struct inclist *file_red, struct inclist *file)
{
    while (file != file_red)
    {
        file = file->i_parent;
        warning ("included from %s\n", file->i_file);
    }
}

int find_includes (struct filepointer *filep, struct inclist *file,
                   struct inclist *file_red, int recursion, bool failOK)
{
    register char *line;
    register int type;
    bool 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->i_file, filep->f_line, line);
                    display_included (file_red, file);
                    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:
            case WARNING:
                warning ("%s: %d: %s\n", file->i_file, filep->f_line, line);
                display_included (file_red, file);
                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);
}
