/** Sends or receives a string to or from the current network package.
* \param str When encoding a packet this is the (NUL-terminated string to
* be sent in the current network package. When decoding this
* is the buffer to decode the string from the network package
* into. When decoding this string is guaranteed to be
* NUL-terminated provided that this buffer is at least 1 byte
* large.
* \param maxlen The buffer size of \c str. For static buffers this means
* sizeof(\c str), for dynamically allocated buffers this is
* whatever number you passed to malloc().
* \note If while decoding \c maxlen is smaller than the actual length of the
* string being decoded, the resulting string (in \c str) will be
* truncated.
*/
BOOL NETstring(char *str, uint16_t maxlen)
{
/*
* Strings sent over the network are prefixed with their length, sent as an
* unsigned 16-bit integer.
*/
// Work out the length of the string if we are encoding
uint16_t len = (NETgetPacketDir() == PACKET_ENCODE) ? strnlen1(str, maxlen) : 0;
char *store;
// Add/fetch the length from the packet
NETuint16_t(&len);
// Map store to the message buffer
store = (char *) &NetMsg.body[NetMsg.size];
// Make sure there is enough data/space left in the packet
if (len + NetMsg.size > sizeof(NetMsg.body) || !NetMsg.status)
{
return NetMsg.status = false;
}
if (NETgetPacketDir() == PACKET_ENCODE)
{
memcpy(store, str, len);
}
else if (NETgetPacketDir() == PACKET_DECODE)
{
// Truncate length if necessary
if (len > maxlen)
{
debug(LOG_ERROR, "NETstring: Decoding packet type %d from %d, buffer size %u truncated at %u",
NetMsg.type, NetMsg.source, len, maxlen);
len = maxlen;
}
memcpy(str, store, len);
// Guarantee NUL-termination
str[len - 1] = '\0';
}
// Increment the size of the message
NetMsg.size += sizeof(len) + len;
return true;
}
size_t
mbsrtowcs (wchar_t *dest, const char **srcp, size_t len, mbstate_t *ps)
{
if (ps == NULL)
ps = &_gl_mbsrtowcs_state;
{
const char *src = *srcp;
if (dest != NULL)
{
wchar_t *destptr = dest;
for (; len > 0; destptr++, len--)
{
size_t src_avail;
size_t ret;
/* An optimized variant of
src_avail = strnlen1 (src, MB_LEN_MAX); */
if (src[0] == '\0')
src_avail = 1;
else if (src[1] == '\0')
src_avail = 2;
else if (src[2] == '\0')
src_avail = 3;
else if (MB_LEN_MAX <= 4 || src[3] == '\0')
src_avail = 4;
else
src_avail = 4 + strnlen1 (src + 4, MB_LEN_MAX - 4);
/* Parse the next multibyte character. */
ret = mbrtowc (destptr, src, src_avail, ps);
if (ret == (size_t)(-2))
/* Encountered a multibyte character that extends past a '\0' byte
or that is longer than MB_LEN_MAX bytes. Cannot happen. */
abort ();
if (ret == (size_t)(-1))
goto bad_input;
if (ret == 0)
{
src = NULL;
/* Here mbsinit (ps). */
break;
}
src += ret;
}
*srcp = src;
return destptr - dest;
}
else
{
/* Ignore dest and len, don't store *srcp at the end, and
don't clobber *ps. */
mbstate_t state = *ps;
size_t totalcount = 0;
for (;; totalcount++)
{
size_t src_avail;
size_t ret;
/* An optimized variant of
src_avail = strnlen1 (src, MB_LEN_MAX); */
if (src[0] == '\0')
src_avail = 1;
else if (src[1] == '\0')
src_avail = 2;
else if (src[2] == '\0')
src_avail = 3;
else if (MB_LEN_MAX <= 4 || src[3] == '\0')
src_avail = 4;
else
src_avail = 4 + strnlen1 (src + 4, MB_LEN_MAX - 4);
/* Parse the next multibyte character. */
ret = mbrtowc (NULL, src, src_avail, &state);
if (ret == (size_t)(-2))
/* Encountered a multibyte character that extends past a '\0' byte
or that is longer than MB_LEN_MAX bytes. Cannot happen. */
abort ();
if (ret == (size_t)(-1))
goto bad_input2;
if (ret == 0)
{
/* Here mbsinit (&state). */
break;
}
src += ret;
}
return totalcount;
}
bad_input:
*srcp = src;
bad_input2:
errno = EILSEQ;
return (size_t)(-1);
}
}
