void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
const void *data, size_t dlen)
{
if (unsigned_add_overflows(pos, len))
die("you want to use way too much memory");
if (pos > sb->len)
die("`pos' is too far after the end of the buffer");
if (pos + len > sb->len)
die("`pos + len' is too far after the end of the buffer");
if (dlen >= len)
strbuf_grow(sb, dlen - len);
memmove(sb->buf + pos + dlen,
sb->buf + pos + len,
sb->len - pos - len);
memcpy(sb->buf + pos, data, dlen);
strbuf_setlen(sb, sb->len + dlen - len);
}
static time_t gm_time_t(timestamp_t time, int tz)
{
int minutes;
minutes = tz < 0 ? -tz : tz;
minutes = (minutes / 100)*60 + (minutes % 100);
minutes = tz < 0 ? -minutes : minutes;
if (minutes > 0) {
if (unsigned_add_overflows(time, minutes * 60))
die("Timestamp+tz too large: %"PRItime" +%04d",
time, tz);
} else if (time < -minutes * 60)
die("Timestamp before Unix epoch: %"PRItime" %04d", time, tz);
time += minutes * 60;
if (date_overflows(time))
die("Timestamp too large for this system: %"PRItime, time);
return (time_t)time;
}
void *patch_delta(const void *src_buf, unsigned long src_size,
const void *delta_buf, unsigned long delta_size,
unsigned long *dst_size)
{
const unsigned char *data, *top;
unsigned char *dst_buf, *out, cmd;
unsigned long size;
if (delta_size < DELTA_SIZE_MIN)
return NULL;
data = delta_buf;
top = (const unsigned char *) delta_buf + delta_size;
/* make sure the orig file size matches what we expect */
size = get_delta_hdr_size(&data, top);
if (size != src_size)
return NULL;
/* now the result size */
size = get_delta_hdr_size(&data, top);
dst_buf = xmallocz(size);
out = dst_buf;
while (data < top) {
cmd = *data++;
if (cmd & 0x80) {
unsigned long cp_off = 0, cp_size = 0;
if (cmd & 0x01) cp_off = *data++;
if (cmd & 0x02) cp_off |= (*data++ << 8);
if (cmd & 0x04) cp_off |= (*data++ << 16);
if (cmd & 0x08) cp_off |= ((unsigned) *data++ << 24);
if (cmd & 0x10) cp_size = *data++;
if (cmd & 0x20) cp_size |= (*data++ << 8);
if (cmd & 0x40) cp_size |= (*data++ << 16);
if (cp_size == 0) cp_size = 0x10000;
if (unsigned_add_overflows(cp_off, cp_size) ||
cp_off + cp_size > src_size ||
cp_size > size)
break;
memcpy(out, (char *) src_buf + cp_off, cp_size);
out += cp_size;
size -= cp_size;
} else if (cmd) {
if (cmd > size)
break;
memcpy(out, data, cmd);
out += cmd;
data += cmd;
size -= cmd;
} else {
/*
* cmd == 0 is reserved for future encoding
* extensions. In the mean time we must fail when
* encountering them (might be data corruption).
*/
error("unexpected delta opcode 0");
goto bad;
}
}
/* sanity check */
if (data != top || size != 0) {
error("delta replay has gone wild");
bad:
free(dst_buf);
return NULL;
}
*dst_size = out - dst_buf;
return dst_buf;
}
