static int getlusize(uint8_t fmt, uint8_t flags, unsigned long ln)
{
struct lib_outstream_s nulloutstream;
lib_nulloutstream(&nulloutstream);
lutoascii(&nulloutstream, fmt, flags, ln);
return nulloutstream.nput;
}
static int getpsize(uint8_t flags, FAR void *p)
{
struct lib_outstream_s nulloutstream;
lib_nulloutstream(&nulloutstream);
ptohex(&nulloutstream, flags, p);
return nulloutstream.nput;
}
static int getdblsize(uint8_t fmt, int trunc, uint8_t flags, double n)
{
struct lib_outstream_s nulloutstream;
lib_nulloutstream(&nulloutstream);
lib_dtoa(&nulloutstream, fmt, trunc, flags, n);
return nulloutstream.nput;
}
int asprintf (FAR char **ptr, const char *fmt, ...)
{
struct lib_outstream_s nulloutstream;
struct lib_memoutstream_s memoutstream;
FAR char *buf;
va_list ap;
int nbytes;
DEBUGASSERT(ptr && fmt);
/* First, use a nullstream to get the size of the buffer. The number
* of bytes returned may or may not include the null terminator.
*/
lib_nulloutstream(&nulloutstream);
va_start(ap, fmt);
nbytes = lib_vsprintf((FAR struct lib_outstream_s *)&nulloutstream, fmt, ap);
va_end(ap);
/* Then allocate a buffer to hold that number of characters, adding one
* for the null terminator.
*/
buf = (FAR char *)malloc(nulloutstream.nput + 1);
if (!buf)
{
return ERROR;
}
/* Initialize a memory stream to write into the allocated buffer. The
* memory stream will reserve one byte at the end of the buffer for the
* null terminator and will not report this in the number of output bytes.
*/
lib_memoutstream((FAR struct lib_memoutstream_s *)&memoutstream,
buf, nulloutstream.nput + 1);
/* Then let lib_vsprintf do it's real thing */
va_start(ap, fmt);
nbytes = lib_vsprintf((FAR struct lib_outstream_s *)&memoutstream.public, fmt, ap);
va_end(ap);
/* Return a pointer to the string to the caller. NOTE: the memstream put()
* method has already added the NUL terminator to the end of the string (not
* included in the nput count).
*
* Hmmm.. looks like the memory would be stranded if lib_vsprintf() returned
* an error. Does that ever happen?
*/
DEBUGASSERT(nbytes < 0 || nbytes == nulloutstream.nput);
*ptr = buf;
return nbytes;
}
