/*LINTLIBRARY*/

#include <stdio.h>
#include "net.h"

/* useful subroutines for dealing with network */

char *ttype[NTTYPES] = {
  "n-channel",
  "p-channel",
  "depletion",
  "pullup",
  "resistor",
  "capacitor"
};

#define HASHSIZE 731

char *pnode();

nptr hash[HASHSIZE];

/* hashing function used in interning symbols */
char lcase[128] = {
 0,	01,	02,	03,	04,	05,	06,	07,
 010,	011,	012,	013,	014,	015,	016,	017,
 020,	021,	022,	023,	024,	025,	026,	027,
 030,	031,	032,	033,	034,	035,	036,	037,
 ' ',	'!',	'"',	'#',	'$',	'%',	'&',	047,
 '(',	')',	'*',	'+',	',',	'-',	'.',	'/',
 '0',	'1',	'2',	'3',	'4',	'5',	'6',	'7',
 '8',	'9',	':',	';',	'<',	'=',	'>',	'?',
 '@',	'a',	'b',	'c',	'd',	'e',	'f',	'g',
 'h',	'i',	'j',	'k',	'l',	'm',	'n',	'o',
 'p',	'q',	'r',	's',	't',	'u',	'v',	'w',
 'x',	'y',	'z',	'[',	0134,	']',	'^',	'_',
 '`',	'a',	'b',	'c',	'd',	'e',	'f',	'g',
 'h',	'i',	'j',	'k',	'l',	'm',	'n',	'o',
 'p',	'q',	'r',	's',	't',	'u',	'v',	'w',
 'x',	'y',	'z',	'{',	'|',	'}',	'~',	0177
};

int sym_hash(name,hashsize)
  register char *name;
  {	register int hashcode = 0;

	while (*name)
	  hashcode = (hashcode*10 + lcase[*name++] - '0') % hashsize;
	return (hashcode<0 ?  hashcode+hashsize : hashcode);
}

/* compare two strings, case doesn't matter */
int str_eql(p,q)
  register char *p,*q;
  {	while (*p) if (lcase[*p++] != lcase[*q++]) return(0);
	return (*q == 0);
}

/* compare pattern with string, case doesn't matter.  "*" wildcard accepted */
int str_match(p,s)
  register char *p,*s;
  {	while (1) {
	  if (*p == '*') {
	    /* skip past multiple wildcards */
	    do p++; while (*p == '*');

	    /* if pattern ends with wild card, automatic match */
	    if (*p == 0) return(1);

	    /* *p now points to first non-wildcard character, find matching
	     * character in string, then recursively match remaining pattern.
	     * if recursive match fails, assume current '*' matches more...
	     */
	    while (*s != 0) {
	      while (lcase[*s] != lcase[*p]) if (*s++ == 0) return(0);
	      if (str_match(p+1,++s)) return(1);
	    }

	    /* couldn't find matching character after '*', no match */
	    return(0);
	  } else if (*p == 0) return(*s == 0);
	  else if (lcase[*p++] != lcase[*s++]) return(0);
	}
}

/* find node in network */
nptr find(name)
  register char *name;
  {	register nptr ntemp;
	register unsigned num = numberp(name);

	for (ntemp = hash[sym_hash(name,HASHSIZE)]; ntemp != 0; ntemp = ntemp->hnext)
	  if ((ntemp->nflags&NAMED && str_eql(name,ntemp->nname)) ||
	      (char *)num==ntemp->nname) {
	    while (ntemp->nflags & ALIAS) ntemp = ntemp->nlink;
	    return(ntemp);
	  }
	return(0);
}

/* insert node into hash table */
n_insert(n)
  register nptr n;
  {	register int temp;
	register char *name;

	name = pnode(n);
	temp = sym_hash(name,HASHSIZE);
	n->hnext = hash[temp];
	hash[temp] = n;
}

/* visit each node in network, calling function passed as arg with current node */
walk_net(fun)
  int (*fun)();
  {	register int index;
	register nptr n;
	int total = 0;

	for (index=0; index<HASHSIZE; index++)
	  for (n = hash[index]; n; n = n->hnext)
	    total += (*fun)(n);

	return(total);
}

/* visit each node in network, calling function passed as arg with any node
 * whose name matches pattern
 */
match_net(pattern,fun,arg)
  char *pattern;
  int (*fun)();
  int arg;
  {	register int index;
	register nptr n;
	int total = 0;

	for (index=0; index<HASHSIZE; index++)
	  for (n = hash[index]; n; n = n->hnext)
	    if (str_match(pattern,pnode(n))) total += (*fun)(n,arg);

	return(total);
}

/* see if asciz string is an integer -- if so, return it; otherwise return 0 */
numberp(s)
  register char *s;
  {	register unsigned num = 0;
	register unsigned temp;

	if (*s == '0') return(0);	/* if it starts with zero, forget it */
	while (*s) {
	  if (*s>='0' && *s<='9') {
	    temp = num*10 + *s - '0';
	    if (temp < num) return(0);
	    else num = temp;
	  }
	  else return(0);
	  s++;
	}
	return(num);
}

/* return pointer to asciz name of node */
char *pnode(n)
  register nptr n;
  {	static char number[50];

	if (n == NULL) return("(null)");
	if (n->nflags & NAMED) return(n->nname);
	sprintf(number,"%ld",(long)n->nname);
	return(number);
}

/* initialize hash table */
init_hash()
  {	register int i;

	for (i = 0; i < HASHSIZE; i += 1) hash[i] = NULL;
}