Panda3D
Loading...
Searching...
No Matches
dcPackerInterface.cxx
Go to the documentation of this file.
1/**
2 * PANDA 3D SOFTWARE
3 * Copyright (c) Carnegie Mellon University. All rights reserved.
4 *
5 * All use of this software is subject to the terms of the revised BSD
6 * license. You should have received a copy of this license along
7 * with this source code in a file named "LICENSE."
8 *
9 * @file dcPackerInterface.cxx
10 * @author drose
11 * @date 2004-06-15
12 */
13
14#include "dcPackerInterface.h"
15#include "dcPackerCatalog.h"
16#include "dcField.h"
17#include "dcParserDefs.h"
18#include "dcLexerDefs.h"
19
20using std::string;
21
22/**
23 *
24 */
25DCPackerInterface::
26DCPackerInterface(const string &name) :
27 _name(name)
28{
29 _has_fixed_byte_size = false;
30 _fixed_byte_size = 0;
31 _has_fixed_structure = false;
32 _has_range_limits = false;
33 _num_length_bytes = 0;
34 _has_nested_fields = false;
35 _num_nested_fields = -1;
36 _pack_type = PT_invalid;
37 _catalog = nullptr;
38}
39
40/**
41 *
42 */
43DCPackerInterface::
44DCPackerInterface(const DCPackerInterface &copy) :
45 _name(copy._name),
46 _has_fixed_byte_size(copy._has_fixed_byte_size),
47 _fixed_byte_size(copy._fixed_byte_size),
48 _has_fixed_structure(copy._has_fixed_structure),
49 _has_range_limits(copy._has_range_limits),
50 _num_length_bytes(copy._num_length_bytes),
51 _has_nested_fields(copy._has_nested_fields),
52 _num_nested_fields(copy._num_nested_fields),
53 _pack_type(copy._pack_type)
54{
55 _catalog = nullptr;
56}
57
58/**
59 *
60 */
61DCPackerInterface::
62~DCPackerInterface() {
63 if (_catalog != nullptr) {
64 delete _catalog;
65 }
66}
67
68/**
69 * Returns the index number to be passed to a future call to DCPacker::seek()
70 * to seek directly to the named field without having to look up the field
71 * name in a table later, or -1 if the named field cannot be found.
72 *
73 * If the named field is nested within a switch or some similar dynamic
74 * structure that reveals different fields based on the contents of the data,
75 * this mechanism cannot be used to pre-fetch the field index number--you must
76 * seek for the field by name.
77 */
79find_seek_index(const string &name) const {
80 return get_catalog()->find_entry_by_name(name);
81}
82
83/**
84 *
85 */
86DCField *DCPackerInterface::
87as_field() {
88 return nullptr;
89}
90
91/**
92 *
93 */
94const DCField *DCPackerInterface::
95as_field() const {
96 return nullptr;
97}
98
99/**
100 *
101 */
102DCSwitchParameter *DCPackerInterface::
103as_switch_parameter() {
104 return nullptr;
105}
106
107/**
108 *
109 */
110const DCSwitchParameter *DCPackerInterface::
111as_switch_parameter() const {
112 return nullptr;
113}
114
115/**
116 *
117 */
118DCClassParameter *DCPackerInterface::
119as_class_parameter() {
120 return nullptr;
121}
122
123/**
124 *
125 */
126const DCClassParameter *DCPackerInterface::
127as_class_parameter() const {
128 return nullptr;
129}
130
131/**
132 * Returns true if this interface is bitwise the same as the interface
133 * described with the indicated formatted string, e.g. "(uint8, uint8,
134 * int16)", or false otherwise.
135 *
136 * If DCFile is not NULL, it specifies the DCFile that was previously loaded,
137 * from which some predefined structs and typedefs may be referenced in the
138 * description string.
139 */
141check_match(const string &description, DCFile *dcfile) const {
142 bool match = false;
143
144 std::istringstream strm(description);
145 dc_init_parser_parameter_description(strm, "check_match", dcfile);
146 dcyyparse();
147 dc_cleanup_parser();
148
149 DCField *field = dc_get_parameter_description();
150 if (field != nullptr) {
151 match = check_match(field);
152 delete field;
153 }
154
155 if (dc_error_count() == 0) {
156 return match;
157 }
158
159 // Parse error: no match is allowed.
160 return false;
161}
162
163/**
164 * Sets the name of this field.
165 */
167set_name(const string &name) {
168 _name = name;
169}
170
171/**
172 * This flavor of get_num_nested_fields is used during unpacking. It returns
173 * the number of nested fields to expect, given a certain length in bytes (as
174 * read from the _num_length_bytes stored in the stream on the push). This
175 * will only be called if _num_length_bytes is nonzero.
176 */
178calc_num_nested_fields(size_t) const {
179 return 0;
180}
181
182/**
183 * Returns the DCPackerInterface object that represents the nth nested field.
184 * This may return NULL if there is no such field (but it shouldn't do this if
185 * n is in the range 0 <= n < get_num_nested_fields()).
186 */
188get_nested_field(int) const {
189 return nullptr;
190}
191
192/**
193 * After a number of fields have been packed via push() .. pack_*() .. pop(),
194 * this is called to confirm that the number of nested fields that were added
195 * is valid for this type. This is primarily useful for array types with
196 * dynamic ranges that can't validate the number of fields any other way.
197 */
200 return true;
201}
202
203/**
204 * Packs the indicated numeric or string value into the stream.
205 */
207pack_double(DCPackData &, double, bool &pack_error, bool &) const {
208 pack_error = true;
209}
210
211/**
212 * Packs the indicated numeric or string value into the stream.
213 */
215pack_int(DCPackData &, int, bool &pack_error, bool &) const {
216 pack_error = true;
217}
218
219/**
220 * Packs the indicated numeric or string value into the stream.
221 */
223pack_uint(DCPackData &, unsigned int, bool &pack_error, bool &) const {
224 pack_error = true;
225}
226
227/**
228 * Packs the indicated numeric or string value into the stream.
229 */
231pack_int64(DCPackData &, int64_t, bool &pack_error, bool &) const {
232 pack_error = true;
233}
234
235/**
236 * Packs the indicated numeric or string value into the stream.
237 */
239pack_uint64(DCPackData &, uint64_t, bool &pack_error, bool &) const {
240 pack_error = true;
241}
242
243/**
244 * Packs the indicated numeric or string value into the stream.
245 */
247pack_string(DCPackData &, const string &, bool &pack_error, bool &) const {
248 pack_error = true;
249}
250
251/**
252 * Packs the indicated numeric or string value into the stream.
253 */
255pack_blob(DCPackData &, const vector_uchar &, bool &pack_error, bool &) const {
256 pack_error = true;
257}
258
259/**
260 * Packs the field's specified default value (or a sensible default if no
261 * value is specified) into the stream. Returns true if the default value is
262 * packed, false if the field doesn't know how to pack its default value.
263 */
265pack_default_value(DCPackData &, bool &) const {
266 return false;
267}
268
269/**
270 * Unpacks the current numeric or string value from the stream.
271 */
273unpack_double(const char *, size_t, size_t &, double &, bool &pack_error, bool &) const {
274 pack_error = true;
275}
276
277/**
278 * Unpacks the current numeric or string value from the stream.
279 */
281unpack_int(const char *, size_t, size_t &, int &, bool &pack_error, bool &) const {
282 pack_error = true;
283}
284
285/**
286 * Unpacks the current numeric or string value from the stream.
287 */
289unpack_uint(const char *, size_t, size_t &, unsigned int &, bool &pack_error, bool &) const {
290 pack_error = true;
291}
292
293/**
294 * Unpacks the current numeric or string value from the stream.
295 */
297unpack_int64(const char *, size_t, size_t &, int64_t &, bool &pack_error, bool &) const {
298 pack_error = true;
299}
300
301/**
302 * Unpacks the current numeric or string value from the stream.
303 */
305unpack_uint64(const char *, size_t, size_t &, uint64_t &, bool &pack_error, bool &) const {
306 pack_error = true;
307}
308
309/**
310 * Unpacks the current numeric or string value from the stream.
311 */
313unpack_string(const char *, size_t, size_t &, string &, bool &pack_error, bool &) const {
314 pack_error = true;
315}
316
317/**
318 * Unpacks the current numeric or string value from the stream.
319 */
321unpack_blob(const char *, size_t, size_t &, vector_uchar &, bool &pack_error, bool &) const {
322 pack_error = true;
323}
324
325/**
326 * Internally unpacks the current numeric or string value and validates it
327 * against the type range limits, but does not return the value. Returns true
328 * on success, false on failure (e.g. we don't know how to validate this
329 * field).
330 */
332unpack_validate(const char *data, size_t length, size_t &p,
333 bool &pack_error, bool &) const {
334 if (!_has_range_limits) {
335 return unpack_skip(data, length, p, pack_error);
336 }
337 return false;
338}
339
340/**
341 * Increments p to the end of the current field without actually unpacking any
342 * data or performing any range validation. Returns true on success, false on
343 * failure (e.g. we don't know how to skip this field).
344 */
346unpack_skip(const char *data, size_t length, size_t &p,
347 bool &pack_error) const {
348 if (_has_fixed_byte_size) {
349 // If this field has a fixed byte size, it's easy to skip.
350 p += _fixed_byte_size;
351 if (p > length) {
352 pack_error = true;
353 }
354 return true;
355 }
356
357 if (_has_nested_fields && _num_length_bytes != 0) {
358 // If we have a length prefix, use that for skipping.
359 if (p + _num_length_bytes > length) {
360 pack_error = true;
361
362 } else {
363 if (_num_length_bytes == 4) {
364 size_t this_length = do_unpack_uint32(data + p);
365 p += this_length + 4;
366 } else {
367 size_t this_length = do_unpack_uint16(data + p);
368 p += this_length + 2;
369 }
370 if (p > length) {
371 pack_error = true;
372 }
373 }
374 return true;
375 }
376
377 // Otherwise, we don't know how to skip this field (presumably it can be
378 // skipped by skipping over its nested fields individually).
379 return false;
380}
381
382/**
383 * Returns the DCPackerCatalog associated with this field, listing all of the
384 * nested fields by name.
385 */
387get_catalog() const {
388 if (_catalog == nullptr) {
389 ((DCPackerInterface *)this)->make_catalog();
390 }
391 return _catalog;
392}
393
394/**
395 * Returns true if this field matches the indicated simple parameter, false
396 * otherwise.
397 */
400 return false;
401}
402
403/**
404 * Returns true if this field matches the indicated class parameter, false
405 * otherwise.
406 */
409 return false;
410}
411
412/**
413 * Returns true if this field matches the indicated switch parameter, false
414 * otherwise.
415 */
418 return false;
419}
420
421/**
422 * Returns true if this field matches the indicated array parameter, false
423 * otherwise.
424 */
427 return false;
428}
429
430/**
431 * Returns true if this field matches the indicated atomic field, false
432 * otherwise.
433 */
436 return false;
437}
438
439/**
440 * Returns true if this field matches the indicated molecular field, false
441 * otherwise.
442 */
445 return false;
446}
447
448/**
449 * Called internally to create a new DCPackerCatalog object.
450 */
451void DCPackerInterface::
452make_catalog() {
453 nassertv(_catalog == nullptr);
454 _catalog = new DCPackerCatalog(this);
455
456 _catalog->r_fill_catalog("", this, nullptr, 0);
457}
This represents an array of some other kind of object, meaning this parameter type accepts an arbitra...
A single atomic field of a Distributed Class, as read from a .dc file.
This represents a class (or struct) object used as a parameter itself.
A single field of a Distributed Class, either atomic or molecular.
Definition dcField.h:37
Represents the complete list of Distributed Class descriptions as read from a .dc file.
Definition dcFile.h:32
A single molecular field of a Distributed Class, as read from a .dc file.
This is a block of data that receives the results of DCPacker.
Definition dcPackData.h:22
This object contains the names of all of the nested fields available within a particular field.
int find_entry_by_name(const std::string &name) const
Returns the index number of the entry with the indicated name, or -1 if no entry has the indicated na...
This defines the internal interface for packing values into a DCField.
const DCPackerCatalog * get_catalog() const
Returns the DCPackerCatalog associated with this field, listing all of the nested fields by name.
virtual void pack_int64(DCPackData &pack_data, int64_t value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual void unpack_blob(const char *data, size_t length, size_t &p, std::vector< unsigned char > &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual void pack_uint(DCPackData &pack_data, unsigned int value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual void unpack_uint64(const char *data, size_t length, size_t &p, uint64_t &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual void unpack_double(const char *data, size_t length, size_t &p, double &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual void pack_uint64(DCPackData &pack_data, uint64_t value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual bool unpack_validate(const char *data, size_t length, size_t &p, bool &pack_error, bool &range_error) const
Internally unpacks the current numeric or string value and validates it against the type range limits...
virtual int calc_num_nested_fields(size_t length_bytes) const
This flavor of get_num_nested_fields is used during unpacking.
virtual bool do_check_match_simple_parameter(const DCSimpleParameter *other) const
Returns true if this field matches the indicated simple parameter, false otherwise.
virtual void unpack_uint(const char *data, size_t length, size_t &p, unsigned int &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual void pack_string(DCPackData &pack_data, const std::string &value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual void unpack_string(const char *data, size_t length, size_t &p, std::string &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual void unpack_int(const char *data, size_t length, size_t &p, int &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual bool do_check_match_atomic_field(const DCAtomicField *other) const
Returns true if this field matches the indicated atomic field, false otherwise.
virtual void pack_int(DCPackData &pack_data, int value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual bool validate_num_nested_fields(int num_nested_fields) const
After a number of fields have been packed via push() .
bool check_match(const DCPackerInterface *other) const
Returns true if the other interface is bitwise the same as this one–that is, a uint32 only matches a ...
virtual bool do_check_match_switch_parameter(const DCSwitchParameter *other) const
Returns true if this field matches the indicated switch parameter, false otherwise.
virtual void pack_double(DCPackData &pack_data, double value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual void unpack_int64(const char *data, size_t length, size_t &p, int64_t &value, bool &pack_error, bool &range_error) const
Unpacks the current numeric or string value from the stream.
virtual DCPackerInterface * get_nested_field(int n) const
Returns the DCPackerInterface object that represents the nth nested field.
virtual bool do_check_match_class_parameter(const DCClassParameter *other) const
Returns true if this field matches the indicated class parameter, false otherwise.
virtual void set_name(const std::string &name)
Sets the name of this field.
virtual bool do_check_match_molecular_field(const DCMolecularField *other) const
Returns true if this field matches the indicated molecular field, false otherwise.
virtual bool do_check_match_array_parameter(const DCArrayParameter *other) const
Returns true if this field matches the indicated array parameter, false otherwise.
virtual void pack_blob(DCPackData &pack_data, const std::vector< unsigned char > &value, bool &pack_error, bool &range_error) const
Packs the indicated numeric or string value into the stream.
virtual bool unpack_skip(const char *data, size_t length, size_t &p, bool &pack_error) const
Increments p to the end of the current field without actually unpacking any data or performing any ra...
virtual bool pack_default_value(DCPackData &pack_data, bool &pack_error) const
Packs the field's specified default value (or a sensible default if no value is specified) into the s...
int find_seek_index(const std::string &name) const
Returns the index number to be passed to a future call to DCPacker::seek() to seek directly to the na...
This is the most fundamental kind of parameter type: a single number or string, one of the DCSubatomi...
This represents a switch object used as a parameter itself, which packs the appropriate fields of the...
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.