1
0
vt100-games/2048/uz80as/utils.c

138 lines
2.3 KiB
C
Raw Normal View History

/* ===========================================================================
* uz80as, an assembler for the Zilog Z80 and several other microprocessors.
*
* Generic functions.
* ===========================================================================
*/
#include "config.h"
#include "utils.h"
#ifndef CTYPE_H
#include <ctype.h>
#endif
#ifndef LIMITS_H
#include <limits.h>
#endif
/*
* Copy [p, q[ to dst and null terminate dst.
*/
void copychars(char *dst, const char *p, const char *q)
{
// int i = 0;
// printf("copychars %x->%x to %x \'", p, q, dst);
while (p != q) {
// printf("%c", *p);
*dst++ = *p++;
// i++;
}
*dst = '\0';
// printf("\' %d %x %d\n", *dst, dst, i);
}
/* Skip space. */
const char *skipws(const char *p)
{
while (isspace(*p))
p++;
return p;
}
/* Return 1 if *p is a valid start character for an identifier. */
int isidc0(char c)
{
return (c == '_') || isalpha(c);
}
/*
* Return 1 if *p is a valid character for an identifier.
* Don't use for the first character.
*/
int isidc(char c)
{
return (c == '_') || (c == '.') || isalnum(c);
}
/* Hash the string in [p, q[ to give a bucket in symtab. */
int hash(const char *p, const char *q, unsigned int tabsz)
{
unsigned int h;
h = 0;
while (p != q) {
h = 31 * h + (unsigned char) *p;
p++;
}
return h % tabsz;
}
/*
* Compare the string in [p, q[ with the null-terminated string s.
* Return 0 if equal.
*/
int scmp(const char *p, const char *q, const char *s)
{
while (p < q) {
if (*p == *s) {
p++;
s++;
} else if (*s == '\0') {
return 1;
} else if (*p < *s) {
return -1;
} else {
return 1;
}
}
if (*s == '\0')
return 0;
else
return -1;
}
/*
* Given a hexadecimal character (in upper case), returns its integer value.
* Returns -1 if c is not a hexadecimal character.
*/
int hexvalu(char c)
{
if (c >= '0' && c <= '9')
return c - '0';
else if (c >= 'A' && c <= 'F')
return (c - 'A') + 10;
else
return -1;
}
/*
* Given a hexadecimal character, returns its integer value.
* Returns -1 if c is not a hexadecimal character.
*/
int hexval(char c)
{
if (c >= 'a' && c <= 'f')
return (c - 'a') + 10;
else
return hexvalu(c);
}
int int_precission(void)
{
static int bits = 0;
unsigned int i;
if (bits > 0)
return bits;
i = INT_MAX;
bits = 0;
while (i) {
bits++;
i >>= 1;
}
return bits;
}