scc

  1#include <ctype.h>
  2#include <stdarg.h>
  3#include <stdio.h>
  4#include <stdlib.h>
  5
  6#include <scc/mach.h>
  7#include "libmach.h"
  8
  9static int
 10lpack(unsigned char *dst, char *fmt, va_list va)
 11{
 12	unsigned char *bp, *cp;
 13	unsigned s;
 14	unsigned long l;
 15	unsigned long long q;
 16	int n;
 17
 18	bp = dst;
 19	while (*fmt) {
 20		switch (*fmt++) {
 21		case '\'':
 22			n = atoi(fmt);
 23			while (isdigit(*fmt))
 24				fmt++;
 25			cp = va_arg(va, unsigned char *);
 26			while (n--)
 27				*bp++ = *cp++;
 28			break;
 29		case 'c':
 30			*bp++ = va_arg(va, unsigned);
 31			break;
 32		case 's':
 33			s = va_arg(va, unsigned);
 34			*bp++ = s;
 35			*bp++ = s >> 8;
 36			break;
 37		case 'l':
 38			l = va_arg(va, unsigned long);
 39			*bp++ = l;
 40			*bp++ = l >> 8;
 41			*bp++ = l >> 16;
 42			*bp++ = l >> 24;
 43			break;
 44		case 'q':
 45			q = va_arg(va, unsigned long long);
 46			*bp++ = q;
 47			*bp++ = q >> 8;
 48			*bp++ = q >> 16;
 49			*bp++ = q >> 24;
 50			*bp++ = q >> 32;
 51			*bp++ = q >> 40;
 52			*bp++ = q >> 48;
 53			*bp++ = q >> 56;
 54			break;
 55		default:
 56			return -1;
 57		}
 58	}
 59
 60	return bp - dst;
 61}
 62
 63static int
 64bpack(unsigned char *dst, char *fmt, va_list va)
 65{
 66	unsigned char *bp, *cp;
 67	unsigned s;
 68	unsigned long l;
 69	unsigned long long q;
 70	int n;
 71
 72	bp = dst;
 73	while (*fmt) {
 74		switch (*fmt++) {
 75		case '\'':
 76			n = atoi(fmt);
 77			while (isdigit(*fmt))
 78				fmt++;
 79			cp = va_arg(va, unsigned char *);
 80			while (n--)
 81				*bp++ = *cp++;
 82			break;
 83		case 'c':
 84			*bp++ = va_arg(va, unsigned);
 85			break;
 86		case 's':
 87			s = va_arg(va, unsigned);
 88			*bp++ = s >> 8;
 89			*bp++ = s;
 90			break;
 91		case 'l':
 92			l = va_arg(va, unsigned long);
 93			*bp++ = l >> 24;
 94			*bp++ = l >> 16;
 95			*bp++ = l >> 8;
 96			*bp++ = l;
 97			break;
 98		case 'q':
 99			q = va_arg(va, unsigned long long);
100			*bp++ = q >> 56;
101			*bp++ = q >> 48;
102			*bp++ = q >> 40;
103			*bp++ = q >> 32;
104			*bp++ = q >> 24;
105			*bp++ = q >> 16;
106			*bp++ = q >> 8;
107			*bp++ = q;
108			break;
109		default:
110			return -1;
111		}
112	}
113
114	return bp - dst;
115}
116
117int
118pack(int order, unsigned char *dst, char *fmt, ...)
119{
120	int r;
121	int (*fn)(unsigned char *dst, char *fmt, va_list va);
122	va_list va;
123
124	va_start(va, fmt);
125	fn = (order == LITTLE_ENDIAN) ? lpack : bpack;
126	r = (*fn)(dst, fmt, va);
127	va_end(va);
128
129	return r;
130}