messroms.de/2007-01-13_www.messroms.de.zip/VZ200/TOOLS/ZCCSRC.ZIP/scc/sym.c

C/C++ Source or Header | 2000-03-05 | 4KB | 265 lines

/*    File sym.c: 2.1 (83/03/20,16:02:19) */
/*% cc -O -c %
 *
 */

#include <stdio.h>
#include "proto.h"
#include "defs.h"
#include "data.h"

/*
 *    declare a static variable
 */
void declglb(int typ, int stor)
{
    int k, j;
    char sname[NAMESIZE];

    for (;;)
    {
        for (;;)
        {
            if (endst())
                return;
            k = 1;
            if (match("*"))
                j = POINTER;
            else
                j = VARIABLE;
            if (!symname(sname))
                illname();
            if (findglb(sname))
                multidef(sname);
            if (match("["))
            {
                k = needsub();
                if (k || stor == EXTERN)
                    j = ARRAY;
                else
                    j = POINTER;
            }
            addglb(sname, j, typ, k, stor);
            break;
        }
        if (!match(","))
            return;
    }
}

/*
 *    declare local variables
 *
 *    works just like "declglb", but modifies machine stack and adds
 *    symbol table entry with appropriate stack offset to find it again
 */
void declloc(int typ, int stclass)
{
    int k, j;
    char sname[NAMESIZE];

    for (;;)
    {
        for (;;)
        {
            if (endst())
                return;
            if (match("*"))
                j = POINTER;
            else
                j = VARIABLE;
            if (!symname(sname))
                illname();
            if (findloc(sname))
                multidef(sname);
            if (match("["))
            {
                k = needsub();
                if (k)
                {
                    j = ARRAY;
                    if (typ == CINT)
                        k = k * intsize();
                }
                else
                {
                    j = POINTER;
                    k = intsize();
                }
            }
            else
            if (typ == CCHAR && j != POINTER)
                k = 1;
            else
                k = intsize();
            if (stclass != LSTATIC)
            {
                k = galign(k);
                stkp = modstk(stkp - k);
                addloc(sname, j, typ, stkp, AUTO);
            }
            else
                addloc(sname, j, typ, k, LSTATIC);
            break;
        }
        if (!match(","))
            return;
    }
}

/*
 *    get required array size
 */
int needsub(void)
{
    int num[1];

    if (match("]"))
        return (0);
    if (!cexpr(num))
    {
        error("must be constant");
        num[0] = 1;
    }
    if (num[0] < 0)
    {
        error("negative size illegal");
        num[0] = (-num[0]);
    }
    needbrack("]");
    return (num[0]);
}

char *findglb(char *sname)
{
    char *ptr;

    ptr = STARTGLB;
    while (ptr != glbptr)
    {
        if (astreq(sname, ptr, NAMEMAX))
            return (ptr);
        ptr = ptr + SYMSIZ;
    }
    return NULL;
}

char *findloc(char *sname)
{
    char *ptr;

    ptr = locptr;
    while (ptr != STARTLOC)
    {
        ptr = ptr - SYMSIZ;
        if (astreq(sname, ptr, NAMEMAX))
            return (ptr);
    }
    return NULL;
}

char *addglb(char *sname, int id, int typ, int value, int stor)
{
    char *ptr;

    if (NULL!=(cptr = findglb(sname)))
        return (cptr);
    if (glbptr >= ENDGLB)
    {
        error("global symbol table overflow");
        return (0);
    }
    cptr = ptr = glbptr;
    while (an(*ptr++ = *sname++))
        ;
    cptr[IDENT] = id;
    cptr[TYPE] = typ;
    cptr[STORAGE] = stor;
    cptr[OFFSET] = value & 0xff;
    cptr[OFFSET + 1] = (value >> 8) & 0xff;
    glbptr = glbptr + SYMSIZ;
    return (cptr);
}

char *addloc(char *sname, int id, int typ, int value, int stclass)
{
    char *ptr;
    int k;

    if (NULL!=(cptr = findloc(sname)))
        return (cptr);
    if (locptr >= ENDLOC)
    {
        error("local symbol table overflow");
        return (0);
    }
    cptr = ptr = locptr;
    while (an(*ptr++ = *sname++))
        ;
    cptr[IDENT] = id;
    cptr[TYPE] = typ;
    cptr[STORAGE] = stclass;
    if (stclass == LSTATIC)
    {
        gbss();
        printlabel(k = getlabel());
        col();
        defstorage();
        onum(value);
        nl();
        gtext();
        value = k;
    }
    else
        value = galign(value);
    cptr[OFFSET] = value & 0xff;
    cptr[OFFSET + 1] = (value >> 8) & 0xff;
    locptr = locptr + SYMSIZ;
    return (cptr);
}

/*
 *    test if next input string is legal symbol name
 */
int symname(char *sname)
{
    int k;
    char c;

    blanks();
    if (!alpha(ch()))
        return (0);
    k = 0;
    while (an(ch()))
    {
        c = gch();
        if (k < NAMESIZE)
            sname[k++] = c;
    }
    sname[k] = 0;
    return (1);
}

void illname(void)
{
    error("illegal symbol name");
}

void multidef(char *sname)
{
    error("already defined");
    comment();
    outstr(sname);
    nl();
}

int glint(char *syment)
{
    int l, u, r;

    l = syment[OFFSET];
    u = syment[OFFSET + 1];
    r = (l & 0xff) + ((u << 8) & ~0x00ff);
    return (r);
}