minor fix for directory protection warning.

[unix-history] / usr / src / usr.bin / rdist / lookup.c

#ifndef lint
static  char *sccsid = "@(#)lookup.c    4.3 (Berkeley) 83/10/10";
#endif

#include "defs.h"

/*
* Define a variable from a command line argument.
*/
define(name)
       char *name;
{
       register char *cp, *s;
       register struct block *bp, *value;

       if (debug)
               printf("define(%s)\n", name);

       cp = index(name, '=');
       if (cp == NULL)
               value = NULL;
       else if (cp[1] == '\0') {
               *cp++ = '\0';
               value = NULL;
       } else if (cp[1] != '(') {
               *cp++ = '\0';
               value = makeblock(NAME, cp);
       } else {
               bp = NULL;
               *cp++ = '\0';
               do
                       cp++;
               while (*cp == ' ' || *cp == '\t');
               for (s = cp; ; s++) {
                       switch (*s) {
                       case ')':
                               *s = '\0';
                       case '\0':
                               break;
                       case ' ':
                       case '\t':
                               *s++ = '\0';
                               while (*s == ' ' || *s == '\t')
                                       s++;
                               if (*s == ')')
                                       *s = '\0';
                               break;
                       default:
                               continue;
                       }
                       if (bp == NULL)
                               value = bp = makeblock(NAME, cp);
                       else {
                               bp->b_next = makeblock(NAME, cp);
                               bp = bp->b_next;
                       }
                       if (*s == '\0')
                               break;
                       cp = s;
               }
       }
       bp = makeblock(VAR, name);
       bp->b_args = value;
       (void) lookup(bp->b_name, bp, 1);
}

static struct block *hashtab[HASHSIZE];

/*
* Lookup name in the table and return a pointer to it.
* Insert == 0 - just do lookup, return NULL if not found.
* insert == 1 - insert name with value, error if already defined.
* insert == 2 - replace name with value if not entered with insert == 1.
*/

struct block *
lookup(name, value, insert)
       char *name;
       struct block *value;
       int insert;
{
       register unsigned n;
       register char *cp;
       register struct block *b, *f;

       if (debug)
               printf("lookup(%s, %x, %d)\n", name, value, insert);

       n = 0;
       for (cp = name; *cp; )
               n += *cp++;
       n %= HASHSIZE;

       for (b = hashtab[n]; b != NULL; b = b->b_next) {
               if (strcmp(name, b->b_name))
                       continue;
               if (insert) {
                       if (b->b_type == NAME) {
                               warn("%s redefined\n", name);
                               f = b->b_args;
                               b->b_args = value->b_args;
                               value->b_args = f;
                       } else if (value->b_type == VAR)
                               fatal("%s redefined\n", name);
               }
               return(b);
       }

       if (!insert)
               fatal("%s not defined", name);

       value->b_next = hashtab[n];
       hashtab[n] = value;
       return(value);
}

/*
* Make a block for lists of variables, commands, etc.
*/
struct block *
makeblock(type, name)
       int type;
       register char *name;
{
       register char *cp;
       register struct block *bp;

       bp = ALLOC(block);
       if (bp == NULL)
               fatal("ran out of memory\n");
       bp->b_type = type;
       bp->b_next = bp->b_args = NULL;
       if (type == NAME || type == VAR) {
               bp->b_name = cp = malloc(strlen(name) + 1);
               if (cp == NULL)
                       fatal("ran out of memory\n");
               while (*cp++ = *name++)
                       ;
       } else
               bp->b_name = NULL;
       return(bp);
}