ssize_t netstring_get_length(VSTREAM *stream)
{
const char *myname = "netstring_get_length";
ssize_t len = 0;
int ch;
for (;;) {
switch (ch = VSTREAM_GETC(stream)) {
case VSTREAM_EOF:
netstring_except(stream, vstream_ftimeout(stream) ?
NETSTRING_ERR_TIME : NETSTRING_ERR_EOF);
case ':':
if (msg_verbose > 1)
msg_info("%s: read netstring length %ld", myname, (long) len);
return (len);
default:
if (!ISDIGIT(ch))
netstring_except(stream, NETSTRING_ERR_FORMAT);
len = len * 10 + ch - '0';
/* vstream_fread() would read zero bytes. Reject input anyway. */
if (len < 0)
netstring_except(stream, NETSTRING_ERR_SIZE);
break;
}
}
}
static void read_data(int unused_event, void *context)
{
SINK_STATE *state = (SINK_STATE *) context;
int fd = vstream_fileno(state->stream);
int count;
/*
* Refill the VSTREAM buffer, if necessary.
*/
if (VSTREAM_GETC(state->stream) == VSTREAM_EOF)
netstring_except(state->stream, vstream_ftimeout(state->stream) ?
NETSTRING_ERR_TIME : NETSTRING_ERR_EOF);
state->count--;
/*
* Flush the VSTREAM buffer. As documented, vstream_fseek() discards
* unread input.
*/
if ((count = vstream_peek(state->stream)) > 0) {
state->count -= count;
if (state->count <= 0) {
send_reply(state);
return;
}
vstream_fpurge(state->stream, VSTREAM_PURGE_BOTH);
}
/*
* Do not block while waiting for the arrival of more data.
*/
event_disable_readwrite(fd);
event_enable_read(fd, read_data, context);
}
VSTRING *netstring_get_data(VSTREAM *stream, VSTRING *buf, ssize_t len)
{
const char *myname = "netstring_get_data";
/*
* Allocate buffer space.
*/
VSTRING_RESET(buf);
VSTRING_SPACE(buf, len);
/*
* Read the payload and absorb the terminator.
*/
if (vstream_fread(stream, STR(buf), len) != len)
netstring_except(stream, vstream_ftimeout(stream) ?
NETSTRING_ERR_TIME : NETSTRING_ERR_EOF);
if (msg_verbose > 1)
msg_info("%s: read netstring data %.*s",
myname, (int) (len < 30 ? len : 30), STR(buf));
netstring_get_terminator(stream);
/*
* Position the buffer.
*/
VSTRING_AT_OFFSET(buf, len);
return (buf);
}
VSTRING *netstring_get(VSTREAM *stream, VSTRING *buf, ssize_t limit)
{
ssize_t len;
len = netstring_get_length(stream);
if (limit && len > limit)
netstring_except(stream, NETSTRING_ERR_SIZE);
netstring_get_data(stream, buf, len);
return (buf);
}
void netstring_get_terminator(VSTREAM *stream)
{
if (VSTREAM_GETC(stream) != ',')
netstring_except(stream, NETSTRING_ERR_FORMAT);
}
