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);
}
}
VBoolean VWriteFile (FILE *f, VAttrList list)
{
DataBlock *db;
VBundle b;
VTypeMethods *methods;
VRepnKind repn;
VPointer value, ptr;
VBoolean result, free_it;
VList data_list;
/* Write the FIL_Vista data file header, attribute list, and delimeter
while queuing on data_list any binary data blocks to be written: */
long offset = 0;
data_list = VListCreate ();
FailTest (fprintf (f, "%s %d ", VFileHeader, VFileVersion));
if (! WriteAttrList (f, list, 1, &data_list, &offset)) {
VListDestroy (data_list, VFree);
return FALSE;
}
FailTest (fputs ("\n" VFileDelimiter, f));
fflush (f);
/* Traverse data_list to write the binary data blocks: */
for (db = VListFirst (data_list); db; db = VListNext (data_list)) {
repn = VGetAttrRepn (& db->posn);
if (repn == VBundleRepn) {
/* A typed value includes its binary data block explicitly: */
VGetAttrValue (& db->posn, NULL, VBundleRepn, & b);
ptr = b->data;
free_it = FALSE;
} else {
/* For any other representation, obtain the binary data block
from its encode_data method: */
VGetAttrValue (& db->posn, NULL, repn, & value);
methods = VRepnMethods (repn);
ptr = (methods->encode_data)
(value, db->list, db->length, & free_it);
if (! ptr)
goto Fail;
}
/* Write the binary data and free the buffer containing it if it was
allocated temporarily by an encode_data method: */
if (db->length > 0) {
result = fwrite (ptr, 1, db->length, f) == db->length;
if (free_it)
VFree (ptr);
if (! result)
goto Fail;
}
}
VListDestroy (data_list, VFree);
return TRUE;
Fail:
VWarning ("VWriteFile: Write to stream failed");
VListDestroy (data_list, VFree);
return FALSE;
}
static VBoolean WriteAttr (FILE *f, VAttrListPosn *posn, int indent, VList *data_list, long *offset)
{
int i;
char *str;
VRepnKind repn;
VAttrList sublist;
VBundle b;
DataBlock *db;
VTypeMethods *methods;
size_t length;
VPointer value;
VBoolean result;
VAttrListPosn subposn;
/* Indent by the specified amount: */
for (i = 0; i < indent; i++)
FailTest (fputc ('\t', f));
indent++;
/* Output the attribute's name: */
FailTest (fprintf (f, "%s: ", VGetAttrName (posn)));
/* Ouput its value: */
switch (repn = VGetAttrRepn (posn)) {
case VAttrListRepn:
VGetAttrValue (posn, NULL, VAttrListRepn, (VPointer) & sublist);
result = WriteAttrList (f, sublist, indent, data_list, offset);
break;
case VBundleRepn:
VGetAttrValue (posn, NULL, VBundleRepn, (VBundle) & b);
if (! WriteString (f, b->type_name))
return FALSE;
FailTest (fputc (' ', f));
/* If it's a typed value with binary data... */
if (b->length > 0) {
/* Include "data" and "length" attributes in its attribute list: */
VPrependAttr (b->list, VLengthAttr, NULL, VLongRepn,
(VLong) b->length);
VPrependAttr (b->list, VDataAttr, NULL, VLongRepn,
(VLong) *offset);
/* Add it to the queue of binary data blocks to be written: */
*offset += b->length;
db = VNew (DataBlock);
db->posn = *posn;
db->list = b->list;
db->length = b->length;
VListAppend (*data_list, db);
}
/* Write the typed value's attribute list: */
result = WriteAttrList (f, b->list, indent, data_list, offset);
/* Remove the "data" and "length" attributes added earlier: */
if (b->length > 0) {
VFirstAttr (b->list, & subposn);
VDeleteAttr (& subposn);
VDeleteAttr (& subposn);
}
break;
case VStringRepn:
VGetAttrValue (posn, NULL, VStringRepn, (VPointer) & str);
result = WriteString (f, str);
break;
default:
if (! (methods = VRepnMethods (repn)) ||
! methods->encode_attr || ! methods->encode_data) {
VWarning ("VWriteFile: "
"%s attribute has unwriteable representation: %s",
VGetAttrName (posn), VRepnName (repn));
return FALSE;
}
/* Write the type name: */
if (! WriteString (f, VRepnName (repn)))
return FALSE;
FailTest (fputc (' ', f));
/* Invoke the object type's encode_attr method to obtain an
attribute list: */
VGetAttrValue (posn, NULL, repn, & value);
sublist = (methods->encode_attr) (value, & length);
/* If binary data is indicated... */
if (length > 0) {
/* Include "data" and "length" attributes in the attr list: */
VPrependAttr (sublist, VLengthAttr, NULL, VLongRepn,
(VLong) length);
VPrependAttr (sublist, VDataAttr, NULL, VLongRepn,
(VLong) *offset);
*offset += length;
}
/* Add the object to the queue of binary data blocks to be written: */
db = VNew (DataBlock);
db->posn = *posn;
db->list = sublist;
db->length = length;
VListAppend (*data_list, db);
/* Write the typed value's attribute list: */
result = WriteAttrList (f, sublist, indent, data_list, offset);
/* Remove the "data" and "length" attributes added earlier: */
if (length > 0) {
VFirstAttr (sublist, & subposn);
VDeleteAttr (& subposn);
VDeleteAttr (& subposn);
}
}
/* Output a trailing newline: */
if (result)
FailTest (fputc ('\n', f));
return result;
Fail:
VWarning ("VWriteFile: Write to stream failed");
return FALSE;
}
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;
}
VAttrList VCopyAttrList (VAttrList list)
{
VAttrList new_list = VCreateAttrList ();
size_t name_size, value_size;
VAttrRec *old_a, *new_a;
VBundle old_b, new_b;
VTypeMethods *methods;
/* For each node of the old list: */
for (old_a = list->next; old_a; old_a = old_a->next) {
/* Compute the amount of storage needed for a copy of the node: */
name_size = strlen (old_a->name);
value_size = (old_a->repn == VStringRepn) ?
strlen ((VStringConst) old_a->value) + 1 : 0;
/* Allocate that size and fill in the node's value: */
new_a = VMalloc (sizeof (VAttrRec) + name_size + value_size);
strcpy (new_a->name, old_a->name);
switch (new_a->repn = old_a->repn) {
case VAttrListRepn:
new_a->value = VCopyAttrList (old_a->value);
break;
case VBundleRepn:
old_b = old_a->value;
new_b = VCreateBundle (old_b->type_name,
VCopyAttrList (old_b->list),
old_b->length, NULL);
if (old_b->length > 0) {
new_b->data = VMalloc (old_b->length);
memcpy (new_b->data, old_b->data, old_b->length);
}
new_a->value = new_b;
break;
case VPointerRepn:
new_a->value = old_a->value;
break;
case VStringRepn:
new_a->value = (VPointer) (new_a->name + name_size + 1);
strcpy (new_a->value, old_a->value);
break;
default:
if (methods = VRepnMethods (new_a->repn))
new_a->value = (methods->copy) (old_a->value);
else VError ("VCopyAttrList: %s attribute has invalid repn %d",
old_a->name, old_a->repn);
}
/* Append it to the new list: */
new_a->next = NULL;
if (new_a->prev = new_list->prev)
new_a->prev->next = new_a;
if (! new_list->next)
new_list->next = new_a;
new_list->prev = new_a;
}
return new_list;
}
