/* byte_string routines * Ben Lynn *//*Copyright (C) 2001 Benjamin Lynn (blynn@cs.stanford.edu)See LICENSE for license*/#include <stdlib.h>#include <string.h>#include "byte_string.h"#include "mm.h"void byte_string_init(byte_string_t bs, int n){    bs->data = (unsigned char *) malloc(n * sizeof(unsigned char));    bs->len = n;    mm_tally("bs", bs->origlen = n, "init");}void byte_string_reinit(byte_string_t bs, int n){    bs->data = (unsigned char *) realloc(bs->data, n * sizeof(unsigned char));    bs->len = n;    mm_tally("bs", n - bs->origlen, "reinit");    bs->origlen = n;}void byte_string_fprintf(FILE *fp, byte_string_t bs, char *format){    int i;    for(i=0; i<bs->len; i++) {	fprintf(fp, format, bs->data[i]);    }}void byte_string_printf(byte_string_t bs, char *format){    int i;    for(i=0; i<bs->len; i++) {	printf(format, bs->data[i]);    }}void byte_string_set(byte_string_t bs, const char *s){    byte_string_init(bs, strlen(s));    memcpy(bs->data, s, bs->len);}void byte_string_assign(byte_string_t bs, byte_string_t src){    bs->data = src->data;    bs->len = src->len;    bs->origlen = src->len;}void byte_string_copy(byte_string_t bs, byte_string_t src){    byte_string_init(bs, src->len);    memcpy(bs->data, src->data, bs->len);}int byte_string_cmp(byte_string_t bs, byte_string_t bs2){    int i;    int result;    i = bs->len < bs2->len ? bs->len : bs2->len;    result = memcmp(bs->data, bs2->data, i);    if (!result) {	if (bs->len == bs2->len) return 0;	else return bs->len > bs2->len;    } else return result;}void byte_string_clear(byte_string_t bs){    if (bs->len) {	mm_tally("bs", -bs->len, "free");	free(bs->data);	bs->len = 0;    } else {	fprintf(stderr, "BUG! double byte_string_clear()\n");    }}void byte_string_set_int(byte_string_t bs, int n){    byte_string_init(bs, 4);    bs->len = 4;    bs->data[0] = (unsigned char) n >> 24;    bs->data[1] = (unsigned char) n >> 16;    bs->data[2] = (unsigned char) n >> 8;    bs->data[3] = (unsigned char) n;}char* charstar_from_byte_string(byte_string_t bs){    char *result;    result = malloc(bs->len + 1);    memcpy(result, bs->data, bs->len);    result[bs->len] = 0;    return result;}int int_from_byte_string(byte_string_t bs){    int result;    if (bs->len != 4) return 0;    result = bs->data[3] + (bs->data[2] << 8)	+ (bs->data[1] << 16) + (bs->data[0] << 24);    return result;}void byte_string_encode_array(byte_string_t bs, byte_string_t *bsa, int n){    int i;    int offset;    bs->len = 2 + 2 * n;    for (i=0; i<n; i++) {	bs->len += bsa[i]->len;    }    bs->data = (unsigned char *) malloc(bs->len * sizeof(unsigned char));    mm_tally("bs", bs->origlen = bs->len, "encode");    bs->data[0] = (unsigned char) (n >> 8);    bs->data[1] = (unsigned char) n;    offset = 2;    for (i=0; i<n; i++) {	bs->data[offset++] = (unsigned char) (bsa[i]->len >> 8);	bs->data[offset++] = (unsigned char) bsa[i]->len;    }    for (i=0; i<n; i++) {	memcpy(&bs->data[offset], bsa[i]->data, bsa[i]->len);	offset += bsa[i]->len;    }    /* alternative representation: harder to check    bs->data[0] = (unsigned char) (n >> 8);    bs->data[1] = (unsigned char) n;    offset = 2;    for (i=0; i<n; i++) {	bs->data[offset] = (unsigned char) (bsa[i]->len >> 8);	bs->data[offset + 1] = (unsigned char) bsa[i]->len;	memcpy(&bs->data[offset + 2], bsa[i]->data, bsa[i]->len);	offset += bsa[i]->len + 2;    }    */}void byte_string_decode_array(byte_string_t **bsarray, int *n, byte_string_t bs){    int i;    int offset;    int total;    byte_string_t *bsa;    if (bs->len < 2) {	*n = 0;	*bsarray = NULL;	return;    }    *n = (bs->data[0] << 8) + bs->data[1];    if (bs->len < 2 + 2 * *n) {	*n = 0;	*bsarray = NULL;	return;    }    bsa = (byte_string_t *) malloc(*n * sizeof(byte_string_t));    offset = 2;    total = 0;    for (i=0; i<*n; i++) {	bsa[i]->len = (bs->data[offset] << 8) + bs->data[offset + 1];	offset += 2;	total += bsa[i]->len;    }    if (bs->len != total + offset) {	*n = 0;	*bsarray = NULL;	free(bsa);	return;    }    for (i=0; i<*n; i++) {	bsa[i]->data = (unsigned char *) malloc(bsa[i]->len * sizeof(unsigned char));	mm_tally("bs", bsa[i]->origlen = bsa[i]->len, "decode");	memcpy(bsa[i]->data, &bs->data[offset], bsa[i]->len);	offset += bsa[i]->len;    }    /* alternative serialization scheme    for (i=0; i<*n; i++) {	bsa[i]->len = (bs->data[offset] << 8) + bs->data[offset + 1];	bsa[i]->data = (unsigned char *) malloc(bsa[i]->len * sizeof(unsigned char));	memcpy(bsa[i]->data, &bs->data[offset + 2], bsa[i]->len);	offset += bsa[i]->len + 2;    }    */    *bsarray = bsa;}//for convenience: same version of above,//but when there's only 2 byte_stringsvoid byte_string_join(byte_string_t bs, byte_string_t bs1, byte_string_t bs2){    byte_string_t bsa[2];    byte_string_assign(bsa[0], bs1);    byte_string_assign(bsa[1], bs2);    byte_string_encode_array(bs, bsa, 2);}void byte_string_split(byte_string_t bs1, byte_string_t bs2, byte_string_t bs){    byte_string_t *bsa;    int n;    byte_string_decode_array(&bsa, &n, bs);    if (n == 2) {	byte_string_assign(bs1, bsa[0]);	byte_string_assign(bs2, bsa[1]);    } else {	int i;	bs1->len = 0;	bs2->len = 0;	for(i=0; i<n; i++) {	    byte_string_clear(bsa[i]);	}    }    free(bsa);}