static void FreeAttrValue (VStringConst routine, VAttrRec *a)
{
VTypeMethods *methods;
switch (a->repn) {
case VAttrListRepn:
VDestroyAttrList (a->value);
break;
case VBundleRepn:
VDestroyBundle (a->value);
break;
case VPointerRepn:
case VStringRepn:
break;
default:
if (! (methods = VRepnMethods (a->repn)))
VError ("%s: %s attribute has invalid repn %d",
routine, a->name, a->repn);
(methods->destroy) (a->value);
}
}
static VBoolean ReadData (FILE *f, VAttrList list, VReadFileFilterProc *filter, long *offset)
{
VAttrListPosn posn, subposn;
VAttrList sublist;
VBundle b;
VRepnKind repn;
VBoolean read_data, data_found, length_found;
VLong data, length;
VTypeMethods *methods;
VPointer value;
for (VFirstAttr (list, & posn); VAttrExists (& posn); VNextAttr (& posn)) {
switch (VGetAttrRepn (& posn)) {
case VAttrListRepn:
/* Recurse on nested attribute list: */
VGetAttrValue (& posn, NULL, VAttrListRepn, & sublist);
if (! ReadData (f, sublist, filter, offset))
return FALSE;
break;
case VBundleRepn:
VGetAttrValue (& posn, NULL, VBundleRepn, & b);
repn = VLookupType (b->type_name);
/* If a filter routine was supplied, ask it whether to bother
with the binary data: */
read_data = ! filter || (*filter) (b, repn);
/* Extract any data and length attributes in the object's value: */
data_found = VLookupAttr (b->list, VDataAttr, & subposn);
if (data_found) {
if (! VGetAttrValue (& subposn, NULL, VLongRepn, & data)) {
VWarning ("VReadFile: "
"%s attribute's data attribute incorrect",
VGetAttrName (& posn));
return FALSE;
}
VDeleteAttr (& subposn);
}
length_found = VLookupAttr (b->list, VLengthAttr, & subposn);
if (length_found) {
if (! VGetAttrValue (& subposn, NULL, VLongRepn, & length)) {
VWarning ("VReadFile: "
"%s attribute's length attribute incorrect",
VGetAttrName (& posn));
return FALSE;
}
VDeleteAttr (& subposn);
}
/* None or both must be present: */
if (data_found ^ length_found) {
VWarning ("VReadFile: %s attribute has %s but not %s",
VGetAttrName (& posn),
data_found ? "data" : "length",
data_found ? "length" : "data");
return FALSE;
}
/* Read the binary data associated with the object: */
if (data_found) {
if (data < *offset) {
VWarning ("VReadFile: "
"%s attribute's data attribute incorrect",
VGetAttrName (& posn));
return FALSE;
}
if (! read_data)
data += length;
/* To seek forward to the start of the data block we first
try fseek. That will fail on a pipe, in which case we
seek by reading. */
if (data != *offset &&
fseek (f, (long) data - *offset, SEEK_CUR) == -1 &&
errno == ESPIPE &&
! MySeek (f, data - *offset)) {
VSystemWarning ("VReadFile: Seek within file failed");
return FALSE;
}
if (read_data) {
b->data = VMalloc (b->length = length);
if (fread (b->data, 1, length, f) != length) {
VWarning ("VReadFile: Read from stream failed");
return FALSE;
}
*offset = data + length;
} else
/* bug: read error occured when bundle was not read
by a filter function. FK 24/03/98 */
*offset = data;
}
/* Recurse to read binary data for sublist attributes: */
if (! ReadData (f, b->list, filter, offset))
return FALSE;
/* If the object's type is registered and has a decode method,
invoke it to decode the binary data: */
if (read_data && repn != VUnknownRepn &&
(methods = VRepnMethods (repn)) && methods->decode) {
if (! (value = (methods->decode) (VGetAttrName (& posn), b)))
return FALSE;
/* Replace the old typed value with the newly decoded one: */
VSetAttrValue (& posn, NULL, repn, value);
VDestroyBundle (b);
}
break;
default:
break;
}
}
return TRUE;
}
