/**
* @param hfile valid GslHFile
* @return offset of first zero byte or -1
*
* Find the offset of the first zero byte in a GslHFile.
* This function is MT-safe and may be called from any thread.
*/
GslLong
gsl_hfile_zoffset (GslHFile *hfile)
{
GslLong zoffset, l;
guint8 sdata[1024], *p;
gboolean seen_zero = FALSE;
errno = EFAULT;
g_return_val_if_fail (hfile != NULL, -1);
g_return_val_if_fail (hfile->ocount > 0, -1);
sfi_mutex_lock (&hfile->mutex);
if (hfile->zoffset > -2) /* got valid offset already */
{
zoffset = hfile->zoffset;
sfi_mutex_unlock (&hfile->mutex);
return zoffset;
}
if (!hfile->ocount) /* bad */
{
sfi_mutex_unlock (&hfile->mutex);
return -1;
}
hfile->ocount += 1; /* keep open for a while */
sfi_mutex_unlock (&hfile->mutex);
/* seek to literal '\0' */
zoffset = 0;
do
{
do
l = gsl_hfile_pread (hfile, zoffset, sizeof (sdata), sdata);
while (l < 0 && errno == EINTR);
if (l < 0)
{
gsl_hfile_close (hfile);
return -1;
}
p = memchr (sdata, 0, l);
seen_zero = p != NULL;
zoffset += seen_zero ? p - sdata : l;
}
while (!seen_zero && l);
if (!seen_zero)
zoffset = -1;
sfi_mutex_lock (&hfile->mutex);
if (hfile->zoffset < -1)
hfile->zoffset = zoffset;
sfi_mutex_unlock (&hfile->mutex);
gsl_hfile_close (hfile);
return zoffset;
}
static void
wave_handle_close (GslDataHandle *dhandle)
{
WaveHandle *whandle = (WaveHandle*) dhandle;
gsl_hfile_close (whandle->hfile);
whandle->hfile = NULL;
}
/**
* @param rfile valid GslRFile
*
* Close and destroy a GslRFile.
*/
void
gsl_rfile_close (GslRFile *rfile)
{
errno = EFAULT;
g_return_if_fail (rfile != NULL);
gsl_hfile_close (rfile->hfile);
sfi_delete_struct (GslRFile, rfile);
errno = 0;
}
