1/* Part of SWI-Prolog 2 3 Author: Jeffrey Rosenwald, extended by Peter Ludemann 4 E-mail: jeffrose@acm.org, peter.ludemann@gmail.com 5 WWW: http://www.swi-prolog.org 6 Copyright (c) 2010-2013, Jeffrey Rosenwald 7 All rights reserved. 8 9 Redistribution and use in source and binary forms, with or without 10 modification, are permitted provided that the following conditions 11 are met: 12 13 1. Redistributions of source code must retain the above copyright 14 notice, this list of conditions and the following disclaimer. 15 16 2. Redistributions in binary form must reproduce the above copyright 17 notice, this list of conditions and the following disclaimer in 18 the documentation and/or other materials provided with the 19 distribution. 20 21 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 29 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 31 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32 POSSIBILITY OF SUCH DAMAGE. 33*/ 34 35:- module(protobufs, 36 [ protobuf_message/2, % ?Template ?Codes 37 protobuf_message/3, % ?Template ?Codes ?Rest 38 protobuf_parse_from_codes/3, % +WireCodes, +MessageType, -Term 39 protobuf_serialize_to_codes/3, % +Term, +MessageType, -WireCodes 40 protobuf_field_is_map/2, % +MessageType, +FieldName 41 protobuf_map_pairs/3 % ?ProtobufTermList, ?DictTag, ?Pairs 42 43 % TODO: Restore the following to the public interface, if 44 % someone needs them. For now, the tests directly specify 45 % them using, e.g. protobufs:uint32_codes(..., ...). 46 % 47 % protobuf_segment_message/2, % ?Segments ?Codes 48 % protobuf_segment_convert/2, % +Form1 ?Form2 49 % uint32_codes/2, 50 % int32_codes/2, 51 % float32_codes/2, 52 % uint64_codes/2, 53 % int64_codes/2, 54 % float64_codes/2, 55 % int64_zigzag/2, 56 % uint32_int32/2, 57 % uint64_int64/2, 58 % uint32_codes_when/2, 59 % int32_codes_when/2, % TODO: unused 60 % float32_codes_when/2, 61 % uint64_codes_when/2, 62 % int64_codes_when/2, % TODO: unused 63 % float64_codes_when/2, 64 % int64_zigzag_when/2, 65 % uint32_int32_when/2, 66 % uint64_int64_when/2, 67 % int64_float64_when/2, 68 % int32_float32_when/2, 69 % protobuf_var_int//1, 70 % protobuf_tag_type//2 71 ]). 72 73:- use_module(library(apply_macros)). % autoload(library(apply), [maplist/3, foldl/4]). 74:- autoload(library(error), [must_be/2, domain_error/2, existence_error/2]). 75:- autoload(library(lists), [append/3]). 76:- autoload(library(utf8), [utf8_codes//1]). 77:- autoload(library(dif), [dif/2]). 78:- autoload(library(dcg/high_order), [sequence//2]). 79:- autoload(library(when), [when/2]). 80:- autoload(library(debug), [assertion/1]). % TODO: remove 81 82:- set_prolog_flag(optimise, true). % For arithmetic using is/2. 83 84/** <module> Google's Protocol Buffers ("protobufs") 85 86Protocol buffers are Google's language-neutral, platform-neutral, 87extensible mechanism for serializing structured data -- think XML, but 88smaller, faster, and simpler. You define how you want your data to be 89structured once. This takes the form of a template that describes the 90data structure. You use this template to encode and decode your data 91structure into wire-streams that may be sent-to or read-from your peers. 92The underlying wire stream is platform independent, lossless, and may be 93used to interwork with a variety of languages and systems regardless of 94word size or endianness. Techniques exist to safely extend your data 95structure without breaking deployed programs that are compiled against 96the "old" format. 97 98The idea behind Google's Protocol Buffers is that you define your 99structured messages using a domain-specific language and tool 100set. Further documentation on this is at 101[https://developers.google.com/protocol-buffers](https://developers.google.com/protocol-buffers). 102 103There are two ways you can use protobufs in Prolog: 104 * with a compiled =|.proto|= file: protobuf_parse_from_codes/3 and 105 protobuf_serialize_to_codes/3. 106 * with a lower-level interface protobuf_message/2, which allows you 107 to define your own domain-specific language for parsing and 108 serializing protobufs. 109 110The protobuf_parse_from_codes/3 and protobuf_serialize_to_codes/3 111interface translates between a "wire stream" and a Prolog term. This 112interface takes advantage of SWI-Prolog's 113[dict](</pldoc/man?section=bidicts>). 114There is a =protoc= plugin (=protoc-gen-swipl=) that generates a 115Prolog file of meta-information that captures the =|.proto|= file's 116definition in the =protobufs= module: 117 * =|proto_meta_normalize(Unnormalized, Normalized)|= 118 * =|proto_meta_package(Package, FileName, Options)|= 119 * =|proto_meta_message_type( Fqn, Package, Name)|= 120 * =|proto_meta_message_type_map_entry( Fqn)|= 121 * =|proto_meta_field_name( Fqn, FieldNumber, FieldName, FqnName)|= 122 * =|proto_meta_field_json_name( FqnName, JsonName)|= 123 * =|proto_meta_field_label( FqnName, LabelRepeatOptional) % 'LABEL_OPTIONAL', 'LABEL_REQUIRED', 'LABEL_REPEATED'|= 124 * =|proto_meta_field_type( FqnName, Type) % 'TYPE_INT32', 'TYPE_MESSAGE', etc|= 125 * =|proto_meta_field_type_name( FqnName, TypeName)|= 126 * =|proto_meta_field_default_value( FqnName, DefaultValue)|= 127 * =|proto_meta_field_option_packed( FqnName)|= 128 * =|proto_meta_enum_type( FqnName, Fqn, Name)|= 129 * =|proto_meta_enum_value( FqnName, Name, Number)|= 130 * =|proto_meta_field_oneof_index( FqnName, Index)|= 131 * =|proto_meta_oneof( FqnName, Index, Name)|= 132 133The protobuf_message/2 interface allows you to define your message 134template as a list of predefined 135Prolog terms that correspond to production rules in the Definite Clause 136Grammar (DCG) that realizes the interpreter. Each production rule has an 137equivalent rule in the protobuf grammar. The process is not unlike 138specifiying the format of a regular expression. To encode a template to 139a wire-stream, you pass a grounded template, =X=, and variable, =Y=, to 140protobuf_message/2. To decode a wire-stream, =Y=, you pass an ungrounded 141template, =X=, along with a grounded wire-stream, =Y=, to 142protobuf_message/2. The interpreter will unify the unbound variables in 143the template with values decoded from the wire-stream. 144 145For an overview and tutorial with examples, see 146[library(protobufs): Google's Protocol Buffers](#protobufs-main) 147Examples of usage may also be found by inspecting 148[[test_protobufs.pl][https://github.com/SWI-Prolog/contrib-protobufs/blob/master/test_protobufs.pl]] 149and the 150[[demo][https://github.com/SWI-Prolog/contrib-protobufs/tree/master/demo]] 151directory, or by looking at the "addressbook" example that is typically 152installed at 153/usr/lib/swi-prolog/doc/packages/examples/protobufs/interop/addressbook.pl 154 155@see https://developers.google.com/protocol-buffers 156@see https://developers.google.com/protocol-buffers/docs/encoding 157@author Jeffrey Rosenwald (JeffRose@acm.org) 158@author Peter Ludemann (peter.ludemann@gmail.org) 159@compat SWI-Prolog 160*/ 161 162:- use_foreign_library(foreign(protobufs)). 163 164%! protobuf_parse_from_codes(+WireCodes:list(int), +MessageType:atom, -Term) is semidet. 165% Process bytes (list of int) that is the serialized form of a message (designated 166% by =MessageType=), creating a Prolog term. 167% 168% =Protoc= must have been run (with the =|--swipl_out=|= option and the resulting 169% top-level _pb.pl file loaded. For more details, see the "protoc" section of the 170% overview documentation. 171% 172% Fails if the message can't be parsed or if the appropriate meta-data from =protoc= 173% hasn't been loaded. 174% 175% All fields that are omitted from the =WireCodes= are set to their 176% default values (typically the empty string or 0, depending on the 177% type; or =|[]|= for repeated groups). There is no way of testing 178% whether a value was specified in =WireCodes= or given its default 179% value (that is, there is no equivalent of the Python 180% implementation's =HasField`). Optional embedded messages and groups 181% do not have any default value -- you must check their existence by 182% using get_dict/3 or similar. If a field is part of a "oneof" set, 183% then none of the other fields is set. You can determine which field 184% had a value by using get_dict/3. 185% 186% @tbd document the generated terms (see library(http/json) and json_read_dict/3) 187% @tbd add options such as =true= and =value_string_as= (similar to json_read_dict/3) 188% @tbd add option for form of the [dict](</pldoc/man?section=bidicts>) tags (fully qualified or not) 189% @tbd add option for outputting fields in the C++/Python/Java order 190% (by field number rather than by field name). 191% 192% @bug Ignores =|.proto|= [extensions](https://developers.google.com/protocol-buffers/docs/proto#extensions). 193% @bug =map= fields don't get special treatment (but see protobuf_map_pairs/3). 194% @bug Generates fields in a different order from the C++, Python, 195% Java implementations, which use the field number to determine 196% field order whereas currently this implementation uses field 197% name. (This isn't stricly speaking a bug, because it's allowed 198% by the specification; but it might cause some surprise.) 199% 200% @param WireCodes Wire format of the message from e.g., read_stream_to_codes/2. 201% (The stream should have options `encoding(octet)` and `type(binary)`, 202% either as options to read_file_to_codes/3 or by calling set_stream/2 203% on the stream to read_stream_to_codes/2.) 204% @param MessageType Fully qualified message name (from the =|.proto|= file's =package= and =message=). 205% For example, if the =package= is =google.protobuf= and the 206% message is =FileDescriptorSet=, then you would use 207% =|'.google.protobuf.FileDescriptorSet'|= or =|'google.protobuf.FileDescriptorSet'|=. 208% If there's no package name, use e.g.: =|'MyMessage|= or =|'.MyMessage'|=. 209% You can see the packages by looking at 210% =|protobufs:proto_meta_package(Pkg,File,_)|= 211% and the message names and fields by 212% =|protobufs:proto_meta_field_name('.google.protobuf.FileDescriptorSet', 213% FieldNumber, FieldName, FqnName)|= (the initial '.' is not optional for these facts, 214% only for the top-level name given to protobuf_serialize_to_codes/3). 215% @param Term The generated term, as nested [dict](</pldoc/man?section=bidicts>)s. 216% @see [library(protobufs): Google's Protocol Buffers](#protobufs-serialize-to-codes) 217% @error version_error(Module-Version) you need to recompile the =Module= 218% with a newer version of =|protoc|=. 219protobuf_parse_from_codes(WireCodes, MessageType0, Term) :- 220 verify_version, 221 must_be(ground, MessageType0), 222 ( proto_meta_normalize(MessageType0, MessageType) 223 -> true 224 ; existence_error(protobuf_package, MessageType0) 225 ), 226 protobuf_segment_message(Segments, WireCodes), 227 % protobuf_segment_message/2 can leave choicepoints, backtracking 228 % through all the possibilities would have combinatoric explosion; 229 % instead use segment_to_term/3 call protobuf_segment_convert/2 to 230 % change segments that were guessed incorrectly. 231 !, 232 maplist(segment_to_term(MessageType), Segments, MsgFields), 233 !, % TODO: remove 234 combine_fields(MsgFields, MessageType{}, Term), 235 !. % TODO: remove? - but proto_meta might have left choicepoints if loaded twice 236 237verify_version :- 238 ( protoc_gen_swipl_version(Module, Version), 239 Version @< [0,9,1] % This must be sync-ed with changes to protoc-gen-swipl 240 -> throw(error(version_error(Module-Version), _)) 241 ; true 242 ). 243 244%! protobuf_serialize_to_codes(+Term:dict, -MessageType:atom, -WireCodes:list(int)) is det. 245% Process a Prolog term into bytes (list of int) that is the serialized form of a 246% message (designated by =MessageType=). 247% 248% =Protoc= must have been run (with the =|--swipl_out=|= option and the resulting 249% top-level _pb.pl file loaded. For more details, see the "protoc" section of the 250% overview documentation. 251% 252% Fails if the term isn't of an appropriate form or if the appropriate 253% meta-data from =protoc= hasn't been loaded, or if a field name is incorrect 254% (and therefore nothing in the meta-data matches it). 255% 256% @bug =map= fields don't get special treatment (but see protobuf_map_pairs/3). 257% @bug =oneof= is not checked for validity. 258% 259% @param Term The Prolog form of the data, as nested [dict](</pldoc/man?section=bidicts>)s. 260% @param MessageType Fully qualified message name (from the =|.proto|= file's =package= and =message=). 261% For example, if the =package= is =google.protobuf= and the 262% message is =FileDescriptorSet=, then you would use 263% =|'.google.protobuf.FileDescriptorSet'|= or =|'google.protobuf.FileDescriptorSet'|=. 264% If there's no package name, use e.g.: =|'MyMessage|= or =|'.MyMessage'|=. 265% You can see the packages by looking at 266% =|protobufs:proto_meta_package(Pkg,File,_)|= 267% and the message names and fields by 268% =|protobufs:proto_meta_field_name('.google.protobuf.FileDescriptorSet', 269% FieldNumber, FieldName, FqnName)|= (the initial '.' is not optional for these facts, 270% only for the top-level name given to protobuf_serialize_to_codes/3). 271% @param WireCodes Wire format of the message, which can be output using 272% =|format('~s', [WireCodes])|=. 273% @see [library(protobufs): Google's Protocol Buffers](#protobufs-serialize-to-codes) 274% @error version_error(Module-Version) you need to recompile the =Module= 275% with a newer version of =|protoc|=. 276% @error existence_error if a field can't be found in the meta-data 277protobuf_serialize_to_codes(Term, MessageType0, WireCodes) :- 278 verify_version, 279 must_be(ground, MessageType0), 280 ( proto_meta_normalize(MessageType0, MessageType) 281 -> true 282 ; existence_error(protobuf_package, MessageType0) 283 ), 284 term_to_segments(Term, MessageType, Segments), 285 !, % TODO: remove 286 protobuf_segment_message(Segments, WireCodes), 287 !. % TODO: remove? - but proto_meta might have left choicepoints if loaded twice 288 289% 290% Map wire type (atom) to its encoding (an int) 291% 292wire_type(varint, 0). % for int32, int64, uint32, uint64, sint32, sint64, bool, enum 293wire_type(fixed64, 1). % for fixed64, sfixed64, double 294wire_type(length_delimited, 2). % for string, bytes, embedded messages, packed repeated fields 295wire_type(start_group, 3). % for groups (deprecated) 296wire_type(end_group, 4). % for groups (deprecated) 297wire_type(fixed32, 5). % for fixed32, sfixed32, float 298 299% 300% basic wire-type processing handled by C-support code in DCG-form 301% 302 303fixed_uint32(X, [A0, A1, A2, A3 | Rest], Rest) :- 304 uint32_codes_when(X, [A0, A1, A2, A3]). 305/* equivalent to: 306fixed_uint32_(X) --> 307 [ A0,A1,A2,A3 ], 308 { uint32_codes_when(X, [A0,A1,A2,A3]) }. 309*/ 310 311fixed_uint64(X, [A0, A1, A2, A3, A4, A5, A6, A7 | Rest], Rest) :- 312 uint64_codes_when(X, [A0, A1, A2, A3, A4, A5, A6, A7]). 313 314fixed_float64(X, [A0, A1, A2, A3, A4, A5, A6, A7 | Rest], Rest) :- 315 float64_codes_when(X, [A0, A1, A2, A3, A4, A5, A6, A7]). 316 317fixed_float32(X, [A0, A1, A2, A3 | Rest], Rest) :- 318 float32_codes_when(X, [A0, A1, A2, A3]). 319 320% 321% Start of the DCG 322% 323 324code_string(N, Codes, Rest, Rest1) :- 325 length(Codes, N), 326 append(Codes, Rest1, Rest), 327 !. 328/* 329code_string(N, Codes) --> 330 { length(Codes, N) }, 331 Codes, !. 332*/ 333 334% 335% deal with Google's method of packing unsigned integers in variable 336% length, modulo 128 strings. 337% 338% protobuf_var_int//1 and protobuf_tag_type//2 productions were rewritten in straight 339% Prolog for speed's sake. 340% 341 342%! protobuf_var_int(?A:int)// is det. 343% Conversion between an int A and a list of codes, using the 344% "varint" encoding. 345% The behvior is undefined if =A= is negative. 346% This is a low-level predicate; normally, you should use 347% template_message/2 and the appropriate template term. 348% e.g. phrase(protobuf_var_int(300), S) => S = [172,2] 349% phrase(protobuf_var_int(A), [172,2]) -> A = 300 350protobuf_var_int(A, [A | Rest], Rest) :- 351 A < 128, 352 !. 353protobuf_var_int(X, [A | Rest], Rest1) :- 354 nonvar(X), 355 X1 is X >> 7, 356 A is 128 + (X /\ 0x7f), 357 protobuf_var_int(X1, Rest, Rest1), 358 !. 359protobuf_var_int(X, [A | Rest], Rest1) :- 360 protobuf_var_int(X1, Rest, Rest1), 361 X is (X1 << 7) + A - 128, 362 !. 363 364%! protobuf_tag_type(?Tag:int, ?WireType:atom)// is det. 365% Conversion between Tag (number) + WireType and wirestream codes. 366% This is a low-level predicate; normally, you should use 367% template_message/2 and the appropriate template term. 368% @arg Tag The item's tag (field number) 369% @arg WireType The item's wire type (see prolog_type//2 for how to 370% convert this to a Prolog type) 371protobuf_tag_type(Tag, WireType, Rest, Rest1) :- 372 nonvar(Tag), nonvar(WireType), 373 wire_type(WireType, WireTypeEncoding), 374 A is Tag << 3 \/ WireTypeEncoding, 375 protobuf_var_int(A, Rest, Rest1), 376 !. 377protobuf_tag_type(Tag, WireType, Rest, Rest1) :- 378 protobuf_var_int(A, Rest, Rest1), 379 WireTypeEncoding is A /\ 0x07, 380 wire_type(WireType, WireTypeEncoding), 381 Tag is A >> 3. 382 383%! prolog_type(?Tag:int, ?PrologType:atom)// is semidet. 384% Match Tag (field number) + PrologType. 385% When Type is a variable, backtracks through all the possibilities 386% for a given wire encoding. 387% Note that 'repeated' isn't here because it's handled by single_message//3. 388% See also segment_type_tag/3. 389prolog_type(Tag, double) --> protobuf_tag_type(Tag, fixed64). 390prolog_type(Tag, integer64) --> protobuf_tag_type(Tag, fixed64). 391prolog_type(Tag, unsigned64) --> protobuf_tag_type(Tag, fixed64). 392prolog_type(Tag, float) --> protobuf_tag_type(Tag, fixed32). 393prolog_type(Tag, integer32) --> protobuf_tag_type(Tag, fixed32). 394prolog_type(Tag, unsigned32) --> protobuf_tag_type(Tag, fixed32). 395prolog_type(Tag, integer) --> protobuf_tag_type(Tag, varint). 396prolog_type(Tag, unsigned) --> protobuf_tag_type(Tag, varint). 397prolog_type(Tag, signed32) --> protobuf_tag_type(Tag, varint). 398prolog_type(Tag, signed64) --> protobuf_tag_type(Tag, varint). 399prolog_type(Tag, boolean) --> protobuf_tag_type(Tag, varint). 400prolog_type(Tag, enum) --> protobuf_tag_type(Tag, varint). 401prolog_type(Tag, atom) --> protobuf_tag_type(Tag, length_delimited). 402prolog_type(Tag, codes) --> protobuf_tag_type(Tag, length_delimited). 403prolog_type(Tag, utf8_codes) --> protobuf_tag_type(Tag, length_delimited). 404prolog_type(Tag, string) --> protobuf_tag_type(Tag, length_delimited). 405prolog_type(Tag, embedded) --> protobuf_tag_type(Tag, length_delimited). 406prolog_type(Tag, packed) --> protobuf_tag_type(Tag, length_delimited). 407 408% 409% The protobuf-2.1.0 grammar allows negative values in enums. 410% But they are encoded as unsigned in the golden message. 411% As such, they use the maximum length of a varint, so it is 412% recommended that they be non-negative. However, that's controlled 413% by the =|.proto|= file. 414% 415:- meta_predicate enumeration(,,). 416 417enumeration(Type) --> 418 { call(Type, Value) }, 419 payload(signed64, Value). 420 421%! payload(?PrologType, ?Payload) is det. 422% Process the codes into =Payload=, according to =PrologType= 423% TODO: payload//2 "mode" is sometimes module-sensitive, sometimes not. 424% payload(enum, A)// has A as a callable 425% all other uses of payload//2, the 2nd arg is not callable. 426% - This confuses check/0; it also makes defining an enumeration 427% more difficult because it has to be defined in module protobufs 428% (see vector_demo.pl, which defines protobufs:commands/2) 429payload(enum, Payload) --> 430 enumeration(Payload). 431payload(double, Payload) --> 432 fixed_float64(Payload). 433payload(integer64, Payload) --> 434 { uint64_int64_when(Payload0, Payload) }, 435 fixed_uint64(Payload0). 436payload(unsigned64, Payload) --> 437 fixed_uint64(Payload). 438payload(float, Payload) --> 439 fixed_float32(Payload). 440payload(integer32, Payload) --> 441 { uint32_int32_when(Payload0, Payload) }, 442 fixed_uint32(Payload0). 443payload(unsigned32, Payload) --> 444 fixed_uint32(Payload). 445payload(integer, Payload) --> 446 { nonvar(Payload), int64_zigzag(Payload, X) }, % TODO: int64_zigzag_when/2 447 !, 448 protobuf_var_int(X). 449payload(integer, Payload) --> 450 protobuf_var_int(X), 451 { int64_zigzag(Payload, X) }. % TODO: int64_zigzag_when/2 452payload(unsigned, Payload) --> 453 protobuf_var_int(Payload), 454 { Payload >= 0 }. 455payload(signed32, Payload) --> % signed32 is not defined by prolog_type//2 456 % for wire-stream compatibility reasons. 457 % signed32 ought to write 5 bytes for negative numbers, but both 458 % the C++ and Python implementations write 10 bytes. For 459 % wire-stream compatibility, we follow C++ and Python, even though 460 % protoc decode appears to work just fine with 5 bytes -- 461 % presumably there are some issues with decoding 5 bytes and 462 % getting the sign extension correct with some 32/64-bit integer 463 % models. See CodedOutputStream::WriteVarint32SignExtended(int32 464 % value) in google/protobuf/io/coded_stream.h. 465 payload(signed64, Payload). 466payload(signed64, Payload) --> 467 % protobuf_var_int//1 cannot handle negative numbers (note that 468 % zig-zag encoding always results in a positive number), so 469 % compute the 64-bit 2s complement, which is what is produced 470 % form C++ and Python. 471 { nonvar(Payload) }, 472 !, 473 { uint64_int64(X, Payload) }, % TODO: uint64_int64_when 474 protobuf_var_int(X). 475payload(signed64, Payload) --> 476 % See comment in previous clause about negative numbers. 477 protobuf_var_int(X), 478 { uint64_int64(X, Payload) }. % TODO: uint64_int64_when 479payload(codes, Payload) --> 480 { nonvar(Payload), 481 !, 482 length(Payload, Len) 483 }, 484 protobuf_var_int(Len), 485 code_string(Len, Payload). 486payload(codes, Payload) --> 487 protobuf_var_int(Len), 488 code_string(Len, Payload). 489payload(utf8_codes, Payload) --> 490 { nonvar(Payload), % TODO: use freeze/2 or when/2 491 !, 492 phrase(utf8_codes(Payload), B) 493 }, 494 payload(codes, B). 495payload(utf8_codes, Payload) --> 496 payload(codes, B), 497 { phrase(utf8_codes(Payload), B) }. 498payload(atom, Payload) --> 499 { nonvar(Payload), 500 atom_codes(Payload, Codes) 501 }, 502 payload(utf8_codes, Codes), 503 !. 504payload(atom, Payload) --> 505 payload(utf8_codes, Codes), 506 { atom_codes(Payload, Codes) }. 507payload(boolean, true) --> 508 payload(unsigned, 1). 509payload(boolean, false) --> 510 payload(unsigned, 0). 511payload(string, Payload) --> 512 { nonvar(Payload) 513 -> string_codes(Payload, Codes) 514 ; true 515 }, 516 % string_codes produces a list of unicode, not bytes 517 payload(utf8_codes, Codes), 518 { string_codes(Payload, Codes) }. 519payload(embedded, protobuf(PayloadSeq)) --> 520 { ground(PayloadSeq), 521 phrase(protobuf(PayloadSeq), Codes) 522 }, 523 payload(codes, Codes), 524 !. 525payload(embedded, protobuf(PayloadSeq)) --> 526 payload(codes, Codes), 527 { phrase(protobuf(PayloadSeq), Codes) }. 528payload(packed, TypedPayloadSeq) --> 529 { TypedPayloadSeq =.. [PrologType, PayloadSeq], % TypedPayloadSeq = PrologType(PayloadSeq) 530 ground(PayloadSeq), 531 phrase(packed_payload(PrologType, PayloadSeq), Codes) 532 }, 533 payload(codes, Codes), 534 !. 535payload(packed, enum(EnumSeq)) --> 536 !, 537 % TODO: combine with next clause 538 % TODO: replace =.. with a predicate that gives all the possibilities - see detag/6. 539 { EnumSeq =.. [ Enum, Values ] }, % EnumSeq = Enum(Values) 540 payload(codes, Codes), 541 { phrase(packed_enum(Enum, Values), Codes) }. 542payload(packed, TypedPayloadSeq) --> 543 payload(codes, Codes), 544 % TODO: replace =.. with a predicate that gives all the possibilities - see detag/6. 545 { TypedPayloadSeq =.. [PrologType, PayloadSeq] }, % TypedPayloadSeq = PrologType(PayloadSeq) 546 { phrase(packed_payload(PrologType, PayloadSeq), Codes) }. 547 548packed_payload(enum, EnumSeq) --> 549 { ground(EnumSeq) }, !, 550 { EnumSeq =.. [EnumType, Values] }, % EnumSeq = EnumType(Values) 551 packed_enum(EnumType, Values). 552packed_payload(PrologType, PayloadSeq) --> 553 sequence_payload(PrologType, PayloadSeq). 554 555% sequence_payload//2 (because sequence//2 isn't compile-time expanded) 556sequence_payload(PrologType, PayloadSeq) --> 557 sequence_payload_(PayloadSeq, PrologType). 558 559sequence_payload_([], _PrologType) --> [ ]. 560sequence_payload_([Payload|PayloadSeq], PrologType) --> 561 payload(PrologType, Payload), 562 sequence_payload_(PayloadSeq, PrologType). 563 564packed_enum(Enum, [ A | As ]) --> 565 % TODO: replace =.. with a predicate that gives all the possibilities - see detag/6. 566 { E =.. [Enum, A] }, 567 payload(enum, E), 568 packed_enum(Enum, As). 569packed_enum(_, []) --> [ ]. 570 571start_group(Tag) --> protobuf_tag_type(Tag, start_group). 572 573end_group(Tag) --> protobuf_tag_type(Tag, end_group). 574% 575% 576nothing([]) --> [], !. 577 578protobuf([Field | Fields]) --> 579 % TODO: don't use =.. -- move logic to single_message 580 ( { Field = repeated_embedded(Tag, protobuf(EmbeddedFields), Items) } 581 -> repeated_embedded_messages(Tag, EmbeddedFields, Items) 582 ; { Field =.. [ PrologType, Tag, Payload] }, % Field = PrologType(Tag, Payload) 583 single_message(PrologType, Tag, Payload), 584 ( protobuf(Fields) 585 ; nothing(Fields) 586 ) 587 ), 588 !. 589 590repeated_message(repeated_enum, Tag, Type, [A | B]) --> 591 % TODO: replace =.. with a predicate that gives all the possibilities - see detag/6. 592 { TypedPayload =.. [Type, A] }, % TypedPayload = Type(A) 593 single_message(enum, Tag, TypedPayload), 594 ( repeated_message(repeated_enum, Tag, Type, B) 595 ; nothing(B) 596 ). 597repeated_message(Type, Tag, [A | B]) --> 598 { Type \= repeated_enum }, 599 single_message(Type, Tag, A), 600 repeated_message(Type, Tag, B). 601repeated_message(_Type, _Tag, A) --> 602 nothing(A). 603 604repeated_embedded_messages(Tag, EmbeddedFields, [protobuf(A) | B]) --> 605 { copy_term(EmbeddedFields, A) }, 606 single_message(embedded, Tag, protobuf(A)), !, 607 repeated_embedded_messages(Tag, EmbeddedFields, B). 608repeated_embedded_messages(_Tag, _EmbeddedFields, []) --> 609 [ ]. 610 611%! single_message(+PrologType:atom, ?Tag, ?Payload)// is det. 612% Processes a single messages (e.g., one item in the list in protobuf([...]). 613% The PrologType, Tag, Payload are from Field =.. [PrologType, Tag, Payload] 614% in the caller 615single_message(repeated, Tag, enum(EnumSeq)) --> 616 !, 617 { EnumSeq =.. [EnumType, Values] }, % EnumSeq = EnumType(Values) 618 repeated_message(repeated_enum, Tag, EnumType, Values). 619single_message(repeated, Tag, Payload) --> 620 !, 621 % TODO: replace =.. with a predicate that gives all the possibilities - see detag/6. 622 { Payload =.. [PrologType, A] }, % Payload = PrologType(A) 623 { PrologType \= enum }, 624 repeated_message(PrologType, Tag, A). 625single_message(group, Tag, A) --> 626 !, 627 start_group(Tag), 628 protobuf(A), 629 end_group(Tag). 630single_message(PrologType, Tag, Payload) --> 631 { PrologType \= repeated, PrologType \= group }, 632 prolog_type(Tag, PrologType), 633 payload(PrologType, Payload). 634 635%! protobuf_message(?Template, ?WireStream) is semidet. 636%! protobuf_message(?Template, ?WireStream, ?Rest) is nondet. 637% 638% Marshals and unmarshals byte streams encoded using Google's 639% Protobuf grammars. protobuf_message/2 provides a bi-directional 640% parser that marshals a Prolog structure to WireStream, according 641% to rules specified by Template. It can also unmarshal WireStream 642% into a Prolog structure according to the same grammar. 643% protobuf_message/3 provides a difference list version. 644% 645% @bug The protobuf specification states that the wire-stream can have 646% the fields in any order and that unknown fields are to be ignored. 647% This implementation assumes that the fields are in the exact order 648% of the definition and match exactly. If you use 649% protobuf_parse_from_codes/3, you can avoid this problem.o 650% 651% @param Template is a protobuf grammar specification. On decode, 652% unbound variables in the Template are unified with their respective 653% values in the WireStream. On encode, Template must be ground. 654% 655% @param WireStream is a code list that was generated by a protobuf 656% encoder using an equivalent template. 657 658protobuf_message(protobuf(TemplateList), WireStream) :- 659 must_be(list, TemplateList), 660 phrase(protobuf(TemplateList), WireStream), 661 !. 662 663protobuf_message(protobuf(TemplateList), WireStream, Residue) :- 664 must_be(list, TemplateList), 665 phrase(protobuf(TemplateList), WireStream, Residue). 666 667%! protobuf_segment_message(+Segments:list, -WireStream:list(int)) is det. 668%! protobuf_segment_message(-Segments:list, +WireStream:list(int)) is det. 669% 670% Low level marshalling and unmarshalling of byte streams. The 671% processing is independent of the =|.proto|= description, similar to 672% the processing done by =|protoc --decode_raw|=. This means that 673% field names aren't shown, only field numbers. 674% 675% For unmarshalling, a simple heuristic is used on length-delimited 676% segments: first interpret it as a message; if that fails, try to 677% interpret as a UTF8 string; otherwise, leave it as a "blob" (if the 678% heuristic was wrong, you can convert to a string or a blob by using 679% protobuf_segment_convert/2). 32-bit and 64-bit numbers are left as 680% codes because they could be either integers or floating point (use 681% int32_codes_when/2, float32_codes_when/2, int64_codes_when/2, 682% uint32_codes_when/2, uint64_codes_when/2, float64_codes_when/2 as 683% appropriate); variable-length numbers ("varint" in the [[Protocol 684% Buffers encoding 685% documentation][https://developers.google.com/protocol-buffers/docs/encoding#varints]]), 686% might require "zigzag" conversion, int64_zigzag_when/2. 687% 688% For marshalling, use the predicates int32_codes_when/2, 689% float32_codes_when/2, int64_codes_when/2, uint32_codes_when/2, 690% uint64_codes_when/2, float64_codes_when/2, int64_zigzag_when/2 to 691% put integer and floating point values into the appropriate form. 692% 693% @bug This predicate is preliminary and may change as additional 694% functionality is added. 695% 696% @param Segments a list containing terms of the following form (=Tag= is 697% the field number; =Codes= is a list of integers): 698% * varint(Tag,Varint) - =Varint= may need int64_zigzag_when/2 699% * fixed64(Tag,Int) - =Int= signed, derived from the 8 codes 700% * fixed32(Tag,Codes) - =Int= is signed, derived from the 4 codes 701% * message(Tag,Segments) 702% * group(Tag,Segments) 703% * string(Tag,String) - =String= is a SWI-Prolog string 704% * packed(Tag,Type(Scalars)) - =Type= is one of 705% =varint=, =fixed64=, =fixed32=; =Scalars= 706% is a list of =Varint= or =Codes=, which should 707% be interpreted as described under those items. 708% Note that the protobuf specification does not 709% allow packed repeated string. 710% * length_delimited(Tag,Codes) 711% * repeated(List) - =List= of segments 712% Of these, =group= is deprecated in the protobuf documentation and 713% shouldn't appear in modern code, having been superseded by nested 714% message types. 715% 716% For deciding how to interpret a length-delimited item (when 717% =Segments= is a variable), an attempt is made to parse the item in 718% the following order (although code should not rely on this order): 719% * message 720% * string (it must be in the form of a UTF string) 721% * packed (which can backtrack through the various =Type=s) 722% * length_delimited - which always is possible. 723% 724% The interpretation of length-delimited items can sometimes guess 725% wrong; the interpretation can be undone by either backtracking or 726% by using protobuf_segment_convert/2 to convert the incorrect 727% segment to a string or a list of codes. Backtracking through all 728% the possibilities is not recommended, because of combinatoric 729% explosion (there is an example in the unit tests); instead, it is 730% suggested that you take the first result and iterate through its 731% items, calling protobuf_segment_convert/2 as needed to reinterpret 732% incorrectly guessed segments. 733% 734% @param WireStream a code list that was generated by a protobuf 735% endoder. 736% 737% @see https://developers.google.com/protocol-buffers/docs/encoding 738protobuf_segment_message(Segments, WireStream) :- 739 phrase(segment_message(Segments), WireStream). 740 741segment_message(Segments) --> 742 sequence_segment(Segments). 743 744% sequence_segment//1 (because sequence//2 isn't compile-time expanded) 745sequence_segment([]) --> [ ]. 746sequence_segment([Segment|Segments]) --> 747 segment(Segment), 748 sequence_segment(Segments). 749 750segment(Segment) --> 751 { nonvar(Segment) }, 752 !, 753 % repeated(List) can be created by field_segment_scalar_or_repeated/7 754 ( { Segment = repeated(Segments) } 755 -> sequence_segment(Segments) 756 ; { segment_type_tag(Segment, Type, Tag) }, 757 protobuf_tag_type(Tag, Type), 758 segment(Type, Tag, Segment) 759 ). 760segment(Segment) --> 761 % { var(Segment) }, 762 protobuf_tag_type(Tag, Type), 763 segment(Type, Tag, Segment). 764 765segment(varint, Tag, varint(Tag,Value)) --> 766 protobuf_var_int(Value). 767segment(fixed64, Tag, fixed64(Tag, Int64)) --> 768 payload(integer64, Int64). 769segment(fixed32, Tag, fixed32(Tag, Int32)) --> 770 payload(integer32, Int32). 771segment(start_group, Tag, group(Tag, Segments)) --> 772 segment_message(Segments), 773 protobuf_tag_type(Tag, end_group). 774segment(length_delimited, Tag, Result) --> 775 segment_length_delimited(Tag, Result). 776 777segment_length_delimited(Tag, Result) --> 778 { nonvar(Result) }, 779 !, 780 { length_delimited_segment(Result, Tag, Codes) }, 781 { length(Codes, CodesLen) }, 782 protobuf_var_int(CodesLen), 783 code_string(CodesLen, Codes). 784segment_length_delimited(Tag, Result) --> 785 % { var(Result) }, 786 protobuf_var_int(CodesLen), 787 code_string(CodesLen, Codes), 788 { length_delimited_segment(Result, Tag, Codes) }. 789 790length_delimited_segment(message(Tag,Segments), Tag, Codes) :- 791 protobuf_segment_message(Segments, Codes). 792length_delimited_segment(group(Tag,Segments), Tag, Codes) :- 793 phrase(segment_group(Tag, Segments), Codes). 794length_delimited_segment(string(Tag,String), Tag, Codes) :- 795 ( nonvar(String) 796 -> string_codes(String, StringCodes), 797 phrase(utf8_codes(StringCodes), Codes) 798 ; phrase(utf8_codes(StringCodes), Codes), 799 string_codes(String, StringCodes) 800 ). 801length_delimited_segment(packed(Tag,Payload), Tag, Codes) :- 802 % We don't know the type of the fields, so we try the 3 803 % possibilities. This has a problem: an even number of fixed32 804 % items can't be distinguished from half the number of fixed64 805 % items; but it's all we can do. The good news is that usually 806 % varint (possibly with zig-zag encoding) is more common because 807 % it's more compact (I don't know whether 32-bit or 64-bit is more 808 % common for floating point). 809 packed_option(Type, Items, Payload), 810 phrase(sequence_payload(Type, Items), Codes). 811length_delimited_segment(length_delimited(Tag,Codes), Tag, Codes). 812 813segment_group(Tag, Segments) --> 814 start_group(Tag), 815 segment_message(Segments), 816 end_group(Tag). 817 818% See also prolog_type//2. Note that this doesn't handle repeated(List), 819% which is used internally (see field_segment_scalar_or_repeated/7). 820segment_type_tag(varint(Tag,_Value), varint, Tag). 821segment_type_tag(fixed64(Tag,_Value), fixed64, Tag). 822segment_type_tag(group(Tag,_Segments), start_group, Tag). 823segment_type_tag(fixed32(Tag,_Value), fixed32, Tag). 824segment_type_tag(length_delimited(Tag,_Codes), length_delimited, Tag). 825segment_type_tag(message(Tag,_Segments), length_delimited, Tag). 826segment_type_tag(packed(Tag,_Payload), length_delimited, Tag). 827segment_type_tag(string(Tag,_String), length_delimited, Tag). 828 829%! detag(+Compound, -Name, -Tag, -Value, List, -CompoundWithList) is semidet. 830% Deconstruct =Compound= or the form =|Name(Tag,Value)|= and create a 831% new =CompoundWithList= that replaces =Value= with =List=. This is 832% used by packed_list/2 to transform =|[varint(1,0),varint(1,1)]|= to 833% =|varint(1,[0,1])|=. 834% 835% Some of =Compound= items are impossible for =packed= with the 836% current protobuf spec, but they don't do any harm. 837detag(varint(Tag,Value), varint, Tag, Value, List, varint(List)). 838detag(fixed64(Tag,Value), fixed64, Tag, Value, List, fixed64(List)). 839detag(fixed32(Tag,Value), fixed32, Tag, Value, List, fixed32(List)). 840detag(length_delimited(Tag,Codes), length_delimited, Tag, Codes, List, length_delimited(List)). 841detag(message(Tag,Segments), message, Tag, Segments, List, message(List)). 842detag(packed(Tag,Payload), packed, Tag, Payload, List, packed(List)). % TODO: delete? 843detag(string(Tag,String), string, Tag, String, List, string(List)). 844 845% See also prolog_type//2, but pick only one for each wirestream type 846% For varint(Items), use one that doesn't do zigzag 847packed_option(integer64, Items, fixed64(Items)). 848packed_option(integer32, Items, fixed32(Items)). 849packed_option(unsigned, Items, varint(Items)). 850% packed_option(integer, Items, varint(Items)). 851% packed_option(double, Items, fixed64(Items)). 852% packed_option(float, Items, fixed32(Items)). 853% packed_option(signed64, Items, varint(Items)). 854% packed_option(boolean, Items, varint(Items)). 855% packed_option(enum, Items, varint(Items)). 856 857%! protobuf_segment_convert(+Form1, ?Form2) is multi. 858% A convenience predicate for dealing with the situation where 859% protobuf_segment_message/2 interprets a segment of the wire stream 860% as a form that you don't want (e.g., as a message but it should have 861% been a UTF8 string). 862% 863% =Form1= is converted back to the original wire stream, then the 864% predicate non-deterimisticly attempts to convert the wire stream to 865% a =|string|= or =|length_delimited|= term (or both: the lattter 866% always succeeds). 867% 868% The possible conversions are: 869% message(Tag,Segments) => string(Tag,String) 870% message(Tag,Segments) => length_delimited(Tag,Codes) 871% string(Tag,String) => length_delimited(Tag,Codes) 872% length_delimited(Tag,Codes) => length_delimited(Tag,Codes) 873% 874% Note that for fixed32, fixed64, only the signed integer forms are 875% given; if you want the floating point forms, then you need to do use 876% int64_float64_when/2 and int32_float32_when/2. 877% 878% For example: 879% ~~~{.pl} 880% ?- protobuf_segment_convert( 881% message(10,[fixed64(13,7309475598860382318)]), 882% string(10,"inputType")). 883% ?- protobuf_segment_convert( 884% message(10,[fixed64(13,7309475598860382318)]), 885% length_delimited(10,[105,110,112,117,116,84,121,112,101])). 886% ?- protobuf_segment_convert( 887% string(10, "inputType"), 888% length_delimited(10,[105,110,112,117,116,84,121,112,101])). 889% ?- forall(protobuf_segment_convert(string(1999,"\x1\\x0\\x0\\x0\\x2\\x0\\x0\\x0\"),Z), writeln(Z)). 890% string(1999, ) 891% packed(1999,fixed64([8589934593])) 892% packed(1999,fixed32([1,2])) 893% packed(1999,varint([1,0,0,0,2,0,0,0])) 894% length_delimited(1999,[1,0,0,0,2,0,0,0]) 895% ~~~ 896% These come from: 897% ~~~{.pl} 898% Codes = [82,9,105,110,112,117,116,84,121,112,101], 899% protobuf_message(protobuf([embedded(T1, protobuf([integer64(T2, I)]))]), Codes), 900% protobuf_message(protobuf([string(T,S)]), Codes). 901% T = 10, T1 = 10, T2 = 13, 902% I = 7309475598860382318, 903% S = "inputType". 904% ~~~ 905% 906% @bug This predicate is preliminary and may change as additional 907% functionality is added. 908% @bug This predicate will sometimes generate unexpected choice points, 909% Such as from =|protobuf_segment_convert(message(10,...), string(10,...))|= 910% 911% @param Form1 =|message(Tag,Pieces)|=, =|string(Tag,String)|=, =|length_delimited(Tag,Codes)|=, 912% =|varint(Tag,Value)|=, =|fixed64(Tag,Value)|=, =|fixed32(Tag,Value)|=. 913% @param Form2 similar to =Form1=. 914protobuf_segment_convert(Form, Form). % for efficiency, don't generate codes 915protobuf_segment_convert(Form1, Form2) :- 916 dif(Form1, Form2), % Form1=Form2 handled by first clause 917 protobuf_segment_message([Form1], WireCodes), 918 phrase(tag_and_codes(Tag, Codes), WireCodes), 919 length_delimited_segment(Form2, Tag, Codes). 920 921tag_and_codes(Tag, Codes) --> 922 protobuf_tag_type(Tag, length_delimited), 923 payload(codes, Codes). 924 925%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 926% Documention of the foreign predicates, which are wrapped and exported. 927 928%! uint32_codes_when(?Uint32, ?Codes) is det. 929% Convert between a 32-bit unsigned integer value and its wirestream codes. 930% This is a low-level predicate; normally, you should use 931% template_message/2 and the appropriate template term. 932% 933% This predicate delays until either =Uint32= or =Codes= is 934% sufficiently instantiated. 935% 936% There is also a non-delayed protobufs:uint32_codes/2 937% 938% SWI-Prolog doesn't have a 32-bit integer type, so 32-bit integer 939% is simulated by doing a range check. 940% 941% @param Uint32 an unsigned integer that's in the 32-bit range 942% @param Codes a list of 4 integers (codes) 943% 944% @error Type,Domain if =Value= or =Codes= are of the wrong 945% type or out of range. 946uint32_codes_when(Uint32, Codes) :- 947 when((nonvar(Uint32) ; ground(Codes)), uint32_codes(Uint32, Codes)). 948 949%! int32_codes_when(?Int32, ?Codes) is det. 950% Convert between a 32-bit signed integer value and its wirestream codes. 951% This is a low-level predicate; normally, you should use 952% template_message/2 and the appropriate template term. 953% 954% This predicate delays until either =Int32= or =Codes= is 955% sufficiently instantiated. 956% 957% There is also a non-delayed protobufs:int32_codes/2 958% 959% SWI-Prolog doesn't have a 32-bit integer type, so 32-bit integer 960% is simulated by doing a range check. 961% 962% @param Int32 an unsigned integer that's in the 32-bit range 963% @param Codes a list of 4 integers (codes) 964% 965% @error Type,Domain if =Value= or =Codes= are of the wrong 966% type or out of range. 967int32_codes_when(Int32, Codes) :- % TODO: unused 968 when((nonvar(Int32) ; ground(Codes)), int32_codes(Int32, Codes)). 969 970%! float32_codes_when(?Value, ?Codes) is det. 971% Convert between a 32-bit floating point value and its wirestream codes. 972% This is a low-level predicate; normally, you should use 973% template_message/2 and the appropriate template term. 974% 975% This predicate delays until either =Value= or =Codes= is 976% sufficiently instantiated. 977% 978% There is also a non-delayed protobufs:float32_codes/2 979% 980% @param Value a floating point number 981% @param Codes a list of 4 integers (codes) 982float32_codes_when(Value, Codes) :- 983 when((nonvar(Value) ; ground(Codes)), float32_codes(Value, Codes)). 984 985%! uint64_codes_when(?Uint64, ?Codes) is det. 986% Convert between a 64-bit unsigned integer value and its wirestream codes. 987% This is a low-level predicate; normally, you should use 988% template_message/2 and the appropriate template term. 989% 990% SWI-Prolog allows integer values greater than 64 bits, so 991% a range check is done. 992% 993% This predicate delays until either =Uint64= or =Codes= is 994% sufficiently instantiated. 995% 996% There is also a non-delayed protobufs:uint64_codes/2 997 998% 999% @param Uint64 an unsigned integer 1000% @param Codes a list of 8 integers (codes) 1001% 1002% @error Type,Domain if =Uint64= or =Codes= are of the wrong 1003% type or out of range. 1004uint64_codes_when(Uint64, Codes) :- 1005 when((nonvar(Uint64) ; ground(Codes)), uint64_codes(Uint64, Codes)). 1006 1007%! int64_codes_when(?Int64, ?Codes) is det. 1008% Convert between a 64-bit signed integer value and its wirestream codes. 1009% This is a low-level predicate; normally, you should use 1010% template_message/2 and the appropriate template term. 1011% 1012% SWI-Prolog allows integer values greater than 64 bits, so 1013% a range check is done. 1014% 1015% This predicate delays until either =Int64= or =Codes= is 1016% sufficiently instantiated. 1017% 1018% There is also a non-delayed protobufs:int64_codes/2 1019 1020% 1021% @param Int64 an unsigned integer 1022% @param Codes a list of 8 integers (codes) 1023% 1024% @error Type,Domain if =Int64= or =Codes= are of the wrong 1025% type or out of range. 1026int64_codes_when(Int64, Codes) :- % TODO: unused 1027 when((nonvar(Int64) ; ground(Codes)), int64_codes(Int64, Codes)). 1028 1029%! float64_codes_when(?Value, ?Codes) is det. 1030% Convert between a 64-bit floating point value and its wirestream codes. 1031% This is a low-level predicate; normally, you should use 1032% template_message/2 and the appropriate template term. 1033% 1034% This predicate delays until either =Value= or =Codes= is 1035% sufficiently instantiated. 1036% 1037% There is also a non-delayed protobufs:float64_codes/2 1038% 1039% @param Value a floating point number 1040% @param Codes a list of 8 integers (codes) 1041% 1042% @error instantiation error if both =Value= and =Codes= are uninstantiated. 1043% 1044% @bug May give misleading exception under some circumstances 1045% (e.g., float64_codes(_, [_,_,_,_,_,_,_,_]). 1046float64_codes_when(Value, Codes) :- 1047 when((nonvar(Value) ; ground(Codes)), float64_codes(Value, Codes)). 1048 1049%! int64_zigzag_when(?Original, ?Encoded) is det. 1050% Convert between a signed integer value and its zigzag encoding, 1051% used for the protobuf =sint32= and =sint64= types. This is a 1052% low-level predicate; normally, you should use template_message/2 and 1053% the appropriate template term. 1054% 1055% SWI-Prolog allows integer values greater than 64 bits, so 1056% a range check is done. 1057% 1058% This predicate delays until either =Original= or =Encoded= is 1059% sufficiently instantiated. 1060% 1061% There is also a non-delayed protobufs:int64_zigzag/2 1062% 1063% @see https://developers.google.com/protocol-buffers/docs/encoding#types 1064% 1065% @param Original an integer in the original form 1066% @param Encoded the zigzag encoding of =Original= 1067% 1068% @error Type,Domain if =Original= or =Encoded= are of the wrong 1069% type or out of range. 1070% 1071% @error instantiation error if both =Original= and =Encoded= are uninstantiated. 1072int64_zigzag_when(Original, Encoded) :- 1073 when((nonvar(Original) ; nonvar(Encoded)), int64_zigzag(Original, Encoded)). 1074 1075%! uint64_int64_when(?Uint64:integer, ?Int64:integer) is det. 1076% Reinterpret-cast between uint64 and int64. For example, 1077% =|uint64_int64(0xffffffffffffffff,-1)|=. 1078% 1079% This predicate delays until either =Uint64= or =Int64= is 1080% sufficiently instantiated. 1081% 1082% There is also a non-delayed protobufs:uint64_int64/2 1083% 1084% @param Uint64 64-bit unsigned integer 1085% @param Int64 64-bit signed integer 1086% 1087% @error Type,Domain if =Value= or =Codes= are of the wrong 1088% type or out of range. 1089% 1090% @error instantiation error if both =Value= and =Codes= are uninstantiated. 1091uint64_int64_when(Uint64, Int64) :- 1092 when((nonvar(Uint64) ; nonvar(Int64)), uint64_int64(Uint64, Int64)). 1093 1094% Reversed argument ordering for maplist/3 1095int64_uint64_when(Int64, Uint64) :- 1096 uint64_int64_when(Uint64, Int64). 1097 1098%! uint32_int32_when(?Uint32, ?Int32) is det. 1099% Reinterpret-case between uint32 and int32. 1100% 1101% This predicate delays until either =Uint32= or =Int32= is 1102% sufficiently instantiated. 1103% 1104% There is also a non-delayed protobufs:uint32_int32/2 1105% 1106% @param Uint32 32-bit unsigned integer (range between 0 and 4294967295). 1107% @param Int32 32-bit signed integer (range between -2147483648 and 2147483647). 1108% 1109% @error Type,Domain if =Int32= or =Uint32= are of the wrong 1110% type or out of range. 1111% 1112% @error instantiation error if both =UInt32= and =Int32= are uninstantiated. 1113uint32_int32_when(Uint32, Int32) :- 1114 when((nonvar(Uint32) ; nonvar(Int32)), uint32_int32(Uint32, Int32)). 1115 1116% Reversed argument ordering for maplist/3 1117int32_uint32_when(Int32, Uint32) :- 1118 1119 uint32_int32_when(Uint32, Int32). 1120 1121%! int64_float64_when(?Int64:integer, ?Float64:float) is det. 1122% Reinterpret-cast between uint64 and float64. For example, 1123% =|int64_float64(3ff0000000000000,1.0)|=. 1124% 1125% This predicate delays until either =Int64= or =Float64= is 1126% sufficiently instantiated. 1127% 1128% There is also a non-delayed protobufs:uint64_int64/2 1129% 1130% @param Int64 64-bit unsigned integer 1131% @param Float64 64-bit float 1132% 1133% @error Type,Domain if =Value= or =Codes= are of the wrong 1134% type or out of range. 1135% 1136% @error instantiation error if both =Value= and =Codes= are uninstantiated. 1137int64_float64_when(Int64, Float64) :- 1138 when((nonvar(Int64) ; nonvar(Float64)), int64_float64(Int64, Float64)). 1139 1140%! int32_float32_when(?Int32:integer, ?Float32:float) is det. 1141% Reinterpret-cast between uint32 and float32. For example, 1142% =|int32_float32(0x3f800000,1.0)|=. 1143% 1144% This predicate delays until either =Int32= or =Float32= is 1145% sufficiently instantiated. 1146% 1147% There is also a non-delayed protobufs:uint32_int32/2 1148% 1149% @param Int32 32-bit unsigned integer 1150% @param Float32 32-bit float 1151% 1152% @error Type,Domain if =Value= or =Codes= are of the wrong 1153% type or out of range. 1154% 1155% @error instantiation error if both =Value= and =Codes= are uninstantiated. 1156int32_float32_when(Int32, Float32) :- 1157 when((nonvar(Int32) ; nonvar(Float32)), int32_float32(Int32, Float32)). 1158 1159 1160%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 1161% 1162% Use protobufs meta-data (see the section on protoc in the "overview" documentation). 1163 1164% The protoc plugin generates the following facts (all starting with "proto_meta_"). 1165% The are documented in protoc-gen-swipl and in the overview section. 1166 1167:- multifile 1168 proto_meta_normalize/2, % (Unnormalized, Normalized) 1169 proto_meta_package/3, % (Package, FileName, Options) 1170 proto_meta_message_type/3, % (Fqn, Package, Name) 1171 proto_meta_message_type_map_entry/1, % (Fqn) 1172 proto_meta_field_name/4, % (Fqn, FieldNumber, FieldName, FqnName) 1173 proto_meta_field_json_name/2, % (FqnName, JsonName) 1174 proto_meta_field_label/2, % (FqnName, LabelRepeatOptional) % LABEL_OPTIONAL, LABEL_REQUIRED, LABEL_REPEATED 1175 proto_meta_field_type/2, % (FqnName, Type) % TYPE_INT32, TYPE_MESSAGE, etc 1176 proto_meta_field_type_name/2, % (FqnName, TypeName) 1177 proto_meta_field_default_value/2, % (FqnName, DefaultValue) 1178 proto_meta_field_option_packed/1, % (FqnName) 1179 proto_meta_enum_type/3, % (FqnName, Fqn, Name) 1180 proto_meta_enum_value/3, % (FqnName, Name, Number) 1181 proto_meta_field_oneof_index/2, % (FqnName, Index) 1182 proto_meta_oneof/3. % (FqnName, Index, Name) 1183 1184proto_meta_enum_value_when(ContextType, EnumValue, IntValue) :- 1185 when((nonvar(EnumValue) ; nonvar(IntValue)), 1186 proto_meta_enum_value_(ContextType, EnumValue, IntValue)). 1187 1188proto_meta_enum_value_(ContextType, EnumValue, IntValue) :- 1189 ( proto_meta_enum_value(ContextType, EnumValue, IntValue) 1190 -> true 1191 ; existence_error(ContextType, EnumValue-IntValue) 1192 ). 1193 1194:- det(segment_to_term/3). 1195%! segment_to_term(+ContextType:atom, +Segment, -FieldAndValue) is det. 1196% ContextType is the type (name) of the containing message 1197% Segment is a segment from protobuf_segment_message/2 1198% TODO: if performance is an issue, this code can be combined with 1199% protobuf_segment_message/2 (and thereby avoid the use of protobuf_segment_convert/2) 1200segment_to_term(ContextType0, Segment, FieldAndValue) => 1201 segment_type_tag(Segment, _, Tag), 1202 field_and_type(ContextType0, Tag, FieldName, _FqnName, ContextType, RepeatOptional, Type), 1203 ( RepeatOptional = repeat_packed 1204 -> convert_segment_packed(Type, ContextType, Tag, Segment, Value) 1205 ; convert_segment(Type, ContextType, Tag, Segment, Value) 1206 ), 1207 !, % TODO: get rid of this? 1208 FieldAndValue = field_and_value(FieldName,RepeatOptional,Value). 1209 1210% :- det(convert_segment_packed/5). % TODO: "succeeded with a choicepoint" 1211%! convert_segment_packed(+Type:atom, +ContextType:atom, +Tag:atom, ?Segment, ?Values) is det. 1212% Reversible on =Segment=, =Values=. 1213% 1214% TODO: these are very similar to convert_segment - can they be combined? 1215 1216convert_segment_packed('TYPE_DOUBLE', _ContextType, Tag, Segment0, Values) => 1217 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, fixed64(Values0)))), 1218 maplist(int64_float64_when, Values0, Values), !. 1219convert_segment_packed('TYPE_FLOAT', _ContextType, Tag, Segment0, Values) => 1220 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, fixed32(Values0)))), 1221 maplist(int32_float32_when, Values0, Values), !. 1222convert_segment_packed('TYPE_INT64', _ContextType, Tag, Segment0, Values) => 1223 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, varint(Values0)))), 1224 maplist(uint64_int64_when, Values0, Values). 1225convert_segment_packed('TYPE_UINT64', _ContextType, Tag, Segment0, Values) => 1226 protobuf_segment_convert(Segment0, packed(Tag, varint(Values))), !. 1227convert_segment_packed('TYPE_INT32', _ContextType, Tag, Segment0, Values) => 1228 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, varint(Values0)))), 1229 maplist(uint32_int32_when, Values0, Values). 1230convert_segment_packed('TYPE_FIXED64', _ContextType, Tag, Segment0, Values) => 1231 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, fixed64(Values0)))), 1232 maplist(int64_uint64_when, Values0, Values). 1233convert_segment_packed('TYPE_FIXED32', _ContextType, Tag, Segment0, Values) => 1234 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, fixed32(Values0)))), 1235 maplist(int32_uint32_when, Values0, Values). 1236convert_segment_packed('TYPE_BOOL', _ContextType, Tag, Segment0, Values) => 1237 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, varint(Values0)))), 1238 maplist(int_bool_when, Values0, Values). 1239% TYPE_STRING isn't allowed TODO: add it anyway? 1240% TYPE_GROUP isn't allowed 1241% TYPE_MESSAGE isn't allowed 1242% TYPE_BYTES isn't allowed TODO: add it anyway? 1243convert_segment_packed('TYPE_UINT32', _ContextType, Tag, Segment0, Values) => 1244 protobuf_segment_convert(Segment0, packed(Tag, varint(Values))), !. 1245convert_segment_packed('TYPE_ENUM', ContextType, Tag, Segment0, Values) => 1246 % uint64_int64_when(...), % TODO! https://github.com/SWI-Prolog/contrib-protobufs/issues/9 1247 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, varint(Values0)))), 1248 maplist(convert_enum(ContextType), Values, Values0). 1249convert_segment_packed('TYPE_SFIXED32', _ContextType, Tag, Segment0, Values) => 1250 protobuf_segment_convert(Segment0, packed(Tag, fixed32(Values))). 1251convert_segment_packed('TYPE_SFIXED64', _ContextType, Tag, Segment0, Values) => 1252 protobuf_segment_convert(Segment0, packed(Tag, fixed64(Values))). 1253convert_segment_packed('TYPE_SINT32', _ContextType, Tag, Segment0, Values) => 1254 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, varint(Values0)))), 1255 maplist(int64_zigzag_when, Values, Values0). 1256convert_segment_packed('TYPE_SINT64', _ContextType, Tag, Segment0, Values) => 1257 freeze(Segment0, protobuf_segment_convert(Segment0, packed(Tag, varint(Values0)))), 1258 maplist(int64_zigzag_when, Values, Values0). 1259% convert_segment_packed(Type, ContextType, Tag, Segment, Values) => % TODO: delete this clause 1260% domain_error(type(type=Type, % TODO: this is a bit funky 1261% context_type=ContextType), 1262% value(segment=Segment, 1263% tag=Tag, 1264% values=Values)). 1265 1266:- det(convert_segment/5). 1267%! convert_segment(+Type:atom, +ContextType:atom, Tag:atom, ?Segment, ?Value) is det. 1268% Compute an appropriate =Value= from the combination of descriptor 1269% "type" (in =Type=) and a =Segment=. 1270% Reversible on =Segment=, =Values=. 1271convert_segment('TYPE_DOUBLE', _ContextType, Tag, Segment0, Value) => 1272 Segment = fixed64(Tag,Int64), 1273 int64_float64_when(Int64, Value), 1274 protobuf_segment_convert(Segment0, Segment), !. 1275convert_segment('TYPE_FLOAT', _ContextType, Tag, Segment0, Value) => 1276 Segment = fixed32(Tag,Int32), 1277 int32_float32_when(Int32, Value), 1278 protobuf_segment_convert(Segment0, Segment), !. 1279convert_segment('TYPE_INT64', _ContextType, Tag, Segment0, Value) => 1280 Segment = varint(Tag,Value0), 1281 uint64_int64_when(Value0, Value), 1282 protobuf_segment_convert(Segment0, Segment), !. 1283convert_segment('TYPE_UINT64', _ContextType, Tag, Segment0, Value) => 1284 Segment = varint(Tag,Value), 1285 protobuf_segment_convert(Segment0, Segment), !. 1286convert_segment('TYPE_INT32', _ContextType, Tag, Segment0, Value) => 1287 Segment = varint(Tag,Value0), 1288 uint32_int32_when(Value0, Value), 1289 protobuf_segment_convert(Segment0, Segment), !. 1290convert_segment('TYPE_FIXED64', _ContextType, Tag, Segment0, Value) => 1291 Segment = fixed64(Tag,Value0), 1292 uint64_int64_when(Value, Value0), 1293 protobuf_segment_convert(Segment0, Segment), !. 1294convert_segment('TYPE_FIXED32', _ContextType, Tag, Segment0, Value) => 1295 Segment = fixed32(Tag,Value0), 1296 uint32_int32_when(Value, Value0), 1297 protobuf_segment_convert(Segment0, Segment), !. 1298convert_segment('TYPE_BOOL', _ContextType, Tag, Segment0, Value) => 1299 Segment = varint(Tag,Value0), 1300 int_bool_when(Value0, Value), 1301 protobuf_segment_convert(Segment0, Segment), !. 1302% convert_segment('TYPE_STRING', _ContextType, Tag, Segment0, Value) => 1303% Segment = string(Tag,ValueStr), 1304% protobuf_segment_convert(Segment0, Segment), !, 1305% ( false % TODO: control whether atom or string with an option 1306% -> atom_string(Value, ValueStr) 1307% ; Value = ValueStr 1308% ). 1309convert_segment('TYPE_STRING', _ContextType, Tag, Segment0, Value) => 1310 % TODO: option to control whether to use atom_string(Value,ValueStr) 1311 Segment = string(Tag,Value), 1312 protobuf_segment_convert(Segment0, Segment), !. 1313convert_segment('TYPE_GROUP', ContextType, Tag, Segment0, Value) => 1314 Segment = group(Tag,MsgSegments), 1315 % TODO: combine with TYPE_MESSAGE code: 1316 ( nonvar(Value) 1317 -> dict_pairs(Value, _, FieldValues), 1318 maplist(field_segment(ContextType), FieldValues, MsgSegments), 1319 protobuf_segment_convert(Segment0, Segment) 1320 ; protobuf_segment_convert(Segment0, Segment), 1321 maplist(segment_to_term(ContextType), MsgSegments, MsgFields), 1322 combine_fields(MsgFields, ContextType{}, Value) 1323 ), !. 1324convert_segment('TYPE_MESSAGE', ContextType, Tag, Segment0, Value) => 1325 Segment = message(Tag,MsgSegments), 1326 ( nonvar(Value) 1327 -> dict_pairs(Value, _, FieldValues), 1328 maplist(field_segment(ContextType), FieldValues, MsgSegments), 1329 protobuf_segment_convert(Segment0, Segment) 1330 ; protobuf_segment_convert(Segment0, Segment), 1331 maplist(segment_to_term(ContextType), MsgSegments, MsgFields), 1332 combine_fields(MsgFields, ContextType{}, Value) 1333 ), !. 1334convert_segment('TYPE_BYTES', _ContextType, Tag, Segment0, Value) => 1335 Segment = length_delimited(Tag,Value), 1336 protobuf_segment_convert(Segment0, Segment), !. 1337convert_segment('TYPE_UINT32', _ContextType, Tag, Segment0, Value) => 1338 Segment = varint(Tag,Value), 1339 protobuf_segment_convert(Segment0, Segment), !. 1340convert_segment('TYPE_ENUM', ContextType, Tag, Segment0, Value) => 1341 Segment = varint(Tag,Value0), 1342 convert_enum(ContextType, Value, Value0), % TODO: negative values: https://github.com/SWI-Prolog/contrib-protobufs/issues/9 1343 protobuf_segment_convert(Segment0, Segment), !. 1344convert_segment('TYPE_SFIXED32', _ContextType, Tag, Segment0, Value) => 1345 Segment = fixed32(Tag,Value), 1346 protobuf_segment_convert(Segment0, Segment), !. 1347convert_segment('TYPE_SFIXED64', _ContextType, Tag, Segment0, Value) => 1348 Segment = fixed64(Tag,Value), 1349 protobuf_segment_convert(Segment0, Segment), !. 1350convert_segment('TYPE_SINT32', _ContextType, Tag, Segment0, Value) => 1351 Segment = varint(Tag,Value0), 1352 int64_zigzag_when(Value, Value0), 1353 protobuf_segment_convert(Segment0, Segment), !. 1354convert_segment('TYPE_SINT64', _ContextType, Tag, Segment0, Value) => 1355 Segment = varint(Tag,Value0), 1356 int64_zigzag_when(Value, Value0), 1357 protobuf_segment_convert(Segment0, Segment), !. 1358 1359convert_enum(ContextType, Enum, Uint) :- 1360 uint64_int64_when(Uint, Int), 1361 proto_meta_enum_value_when(ContextType, Enum, Int). 1362 1363% TODO: use options to translate to/from false, true (see json_read/3) 1364int_bool(0, false). 1365int_bool(1, true). 1366 1367int_bool_when(Int, Bool) :- 1368 when((nonvar(Int) ; nonvar(Bool)), int_bool(Int, Bool)). 1369 1370%! add_defaulted_fields(+Value0:dict, ContextType:atom, -Value:dict) is det. 1371add_defaulted_fields(Value0, ContextType, Value) :- 1372 % Can use bagof or findall if we know that there aren't any 1373 % duplicated proto_meta_field_name/4 rules, although this isn't 1374 % strictly necessary (just avoids processing a field twice). 1375 ( setof(Name-DefaultValue, message_field_default(ContextType, Name, DefaultValue), DefaultValues) 1376 -> true 1377 ; DefaultValues = [] 1378 ), 1379 foldl(add_empty_field_if_missing, DefaultValues, Value0, Value). 1380 1381%! message_field_default(+ContextType:atom, Name:atom, -DefaultValue) is semidet. 1382message_field_default(ContextType, Name, DefaultValue) :- 1383 proto_meta_field_name(ContextType, _FieldNumber, Name, Fqn), 1384 proto_meta_field_default_value(Fqn, DefaultValue), 1385 % If the field is part of a "oneof" group, then there will be a 1386 % proto_meta_oneof entry for it (using the oneof_index). All 1387 % fields have a oneof_index, but our code doesn't depend on that. 1388 \+ (proto_meta_field_oneof_index(Fqn, OneofIndex), 1389 proto_meta_oneof(ContextType, OneofIndex, _)). 1390 1391add_empty_field_if_missing(FieldName-DefaultValue, Dict0, Dict) :- 1392 ( get_dict(FieldName, Dict0, _) 1393 -> Dict = Dict0 1394 ; put_dict(FieldName, Dict0, DefaultValue, Dict) 1395 ). 1396 1397:- det(combine_fields/3). 1398%! combine_fields(+Fields:list, +MsgDict0, -MsgDict) is det. 1399% Combines the fields into a dict and sets missing fields to their default values. 1400% If the field is marked as 'norepeat' (optional/required), then the last 1401% occurrence is kept (as per the protobuf wire spec) 1402% If the field is marked as 'repeat', then all the occurrences 1403% are put into a list, in order. 1404% This code assumes that fields normally occur all together, but can handle 1405% (less efficiently) fields not occurring together, as is allowed 1406% by the protobuf spec. 1407combine_fields([], MsgDict0, MsgDict) => 1408 is_dict(MsgDict0, ContextType), 1409 add_defaulted_fields(MsgDict0, ContextType, MsgDict). 1410combine_fields([field_and_value(Field,norepeat,Value)|Fields], MsgDict0, MsgDict) => 1411 put_dict(Field, MsgDict0, Value, MsgDict1), 1412 combine_fields(Fields, MsgDict1, MsgDict). 1413combine_fields([field_and_value(Field,repeat_packed,Values0)|Fields], MsgDict0, MsgDict) => 1414 ( get_dict(Field, MsgDict0, ExistingValues) 1415 -> append(ExistingValues, Values0, Values) 1416 ; Values = Values0 1417 ), 1418 put_dict(Field, MsgDict0, Values, MsgDict1), 1419 combine_fields(Fields, MsgDict1, MsgDict). 1420combine_fields([field_and_value(Field,repeat,Value)|Fields], MsgDict0, MsgDict) => 1421 combine_fields_repeat(Fields, Field, NewValues, RestFields), 1422 ( get_dict(Field, MsgDict0, ExistingValues) 1423 -> append(ExistingValues, [Value|NewValues], Values) 1424 ; Values = [Value|NewValues] 1425 ), 1426 put_dict(Field, MsgDict0, Values, MsgDict1), 1427 combine_fields(RestFields, MsgDict1, MsgDict). 1428 1429:- det(combine_fields_repeat/4). 1430%! combine_fields_repeat(+Fields:list, Field:atom, -Values:list, RestFields:list) is det. 1431% Helper for combine_fields/3 1432% Stops at the first item that doesn't match =Field= - the assumption 1433% is that all the items for a field will be together and if they're 1434% not, they would be combined outside this predicate. 1435% 1436% @param Fields a list of fields (Field-Repeat-Value) 1437% @param Field the name of the field that is being combined 1438% @param Values gets the Value items that match Field 1439% @param RestFields gets any left-over fields 1440combine_fields_repeat([], _Field, Values, RestFields) => Values = [], RestFields = []. 1441combine_fields_repeat([Field-repeat-Value|Fields], Field, Values, RestFields) => 1442 Values = [Value|Values2], 1443 combine_fields_repeat(Fields, Field, Values2, RestFields). 1444combine_fields_repeat(Fields, _Field, Values, RestFields) => Values = [], RestFields = Fields. 1445 1446:- det(field_and_type/7). 1447%! field_and_type(+ContextType:atom, +Tag:int, -FieldName:atom, -FqnName:atom, -ContextType2:atom, -RepeatOptional:atom, -Type:atom) is det. 1448% Lookup a =ContextType= and =Tag= to get the field name, type, etc. 1449field_and_type(ContextType, Tag, FieldName, FqnName, ContextType2, RepeatOptional, Type) => 1450 assertion(ground(ContextType)), % TODO: remove 1451 assertion(ground(Tag)), % TODO: remove 1452 ( proto_meta_field_name(ContextType, Tag, FieldName, FqnName), 1453 proto_meta_field_type_name(FqnName, ContextType2), 1454 fqn_repeat_optional(FqnName, RepeatOptional), 1455 proto_meta_field_type(FqnName, Type) 1456 -> true % Remove choicepoint, if JITI didn't do the right thing. 1457 ; existence_error(ContextType, Tag) 1458 ). 1459 1460%! fqn_repeat_optional(+FqnName:atom, -RepeatOptional:atom) is det. 1461% Lookup up proto_meta_field_label(FqnName, _), proto_meta_field_option_packed(FqnName) 1462% and set RepeatOptional to one of 1463% =norepeat=, =repeat=, =repeat_packed=. 1464fqn_repeat_optional(FqnName, RepeatOptional) => 1465 % TODO: existence_error if \+ proto_meta_field_label 1466 proto_meta_field_label(FqnName, LabelRepeatOptional), 1467 ( LabelRepeatOptional = 'LABEL_REPEATED', 1468 proto_meta_field_option_packed(FqnName) 1469 -> RepeatOptional = repeat_packed 1470 ; \+ proto_meta_field_option_packed(FqnName), % validity check 1471 fqn_repeat_optional_2(LabelRepeatOptional, RepeatOptional) 1472 ). 1473 1474:- det(fqn_repeat_optional_2/2). 1475%! fqn_repeat_optional_2(+DescriptorLabelEnum:atom, -RepeatOrEmpty:atom) is det. 1476% Map the descriptor "label" to 'repeat' or 'norepeat'. 1477% From proto_meta_enum_value('.google.protobuf.FieldDescriptorProto.Label', Label, _). 1478fqn_repeat_optional_2('LABEL_OPTIONAL', norepeat). 1479fqn_repeat_optional_2('LABEL_REQUIRED', norepeat). 1480fqn_repeat_optional_2('LABEL_REPEATED', repeat). 1481 1482%! field_descriptor_label_repeated(+Label:atom) is semidet. 1483% From proto_meta_enum_value('.google.protobuf.FieldDescriptorProto.Label', 'LABEL_REPEATED', _). 1484% TODO: unused 1485field_descriptor_label_repeated('LABEL_REPEATED'). 1486 1487%! field_descriptor_label_single(+Label:atom) is semidet. 1488% From proto_meta_enum_value('.google.protobuf.FieldDescriptorProto.Label', Label, _). 1489field_descriptor_label_single('LABEL_OPTIONAL'). 1490field_descriptor_label_single('LABEL_REQUIRED'). 1491 1492:- det(term_to_segments/3). 1493%! term_to_segments(+Term:dict, +MessageType:atom, Segments) is det. 1494% Recursively traverse a =Term=, generating message segments 1495term_to_segments(Term, MessageType, Segments) :- 1496 dict_pairs(Term, _, FieldValues), 1497 maplist(field_segment(MessageType), FieldValues, Segments). 1498 1499:- det(field_segment/3). 1500% MessageType is the FQN of the field type (e.g., '.test.Scalars1') 1501% FieldName-Value is from the dict_pairs of the term. 1502% TODO: Throw an error if proto_meta_field_name/4 fails (need to make 1503% sure of all the possible uses of field_segment/3 and that 1504% nothing depends on it being able to fail without an error). 1505field_segment(MessageType, FieldName-Value, Segment) :- 1506 ( proto_meta_field_name(MessageType, Tag, FieldName, FieldFqn), 1507 proto_meta_field_type(FieldFqn, FieldType), 1508 proto_meta_field_type_name(FieldFqn, FieldTypeName), 1509 proto_meta_field_label(FieldFqn, Label) 1510 -> true % Remove choicepoint, if JITI didn't do the right thing. 1511 ; existence_error(MessageType, FieldName-Value) 1512 ), 1513 ( proto_meta_field_option_packed(FieldFqn) 1514 -> Packed = packed 1515 ; Packed = not_packed 1516 ), 1517 field_segment_scalar_or_repeated(Label, Packed, FieldType, Tag, FieldTypeName, Value, Segment), 1518 !. % TODO: remove 1519 1520:- det(field_segment_scalar_or_repeated/7). 1521%! field_segment_scalar_or_repeated(+Label, +Packed, +FieldType, +Tag, +FieldTypeName, ?Value, Segment) is det. 1522% =FieldType= is from the =|.proto|= meta information ('TYPE_SINT32', etc.) 1523field_segment_scalar_or_repeated('LABEL_OPTIONAL', not_packed, FieldType, Tag, FieldTypeName, Value, Segment) => 1524 convert_segment(FieldType, FieldTypeName, Tag, Segment, Value). 1525field_segment_scalar_or_repeated('LABEL_REQUIRED', not_packed, FieldType, Tag, FieldTypeName, Value, Segment) => % same as LABEL_OPTIONAL 1526 convert_segment(FieldType, FieldTypeName, Tag, Segment, Value). 1527field_segment_scalar_or_repeated('LABEL_REPEATED', packed, FieldType, Tag, FieldTypeName, Values, Segment) => 1528 Segment = packed(Tag,FieldValues), 1529 maplist(convert_segment_v_s(FieldType, FieldTypeName, Tag), Values, Segments0), 1530 packed_list(Segments0, FieldValues). 1531field_segment_scalar_or_repeated('LABEL_REPEATED', not_packed, FieldType, Tag, FieldTypeName, Values, Segment) => 1532 Segment = repeated(Segments), 1533 maplist(convert_segment_v_s(FieldType, FieldTypeName, Tag), Values, Segments). 1534% field_segment_scalar_or_repeated(Label, Packed, FieldType, Tag, FieldTypeName, Value, Segment) :- % TODO: delete this clause 1535% domain_error(type(field_type=FieldType, % TODO: this is a bit funky 1536% label=Label, 1537% packed=Packed), 1538% value(tag=Tag, field_type_name=FieldTypeName, value=Value, segment=Segment)). 1539 1540convert_segment_v_s(FieldType, FieldTypeName, Tag, Value, Segment) :- 1541 convert_segment(FieldType, FieldTypeName, Tag, Segment, Value). 1542 1543% Convert [varint(1,10),varint(1,20)] to varint(1,[10,20]). 1544packed_list([], []). 1545packed_list([T1|Ts], PackedList) :- 1546 detag(T1, Functor, Tag, _V1, List, PackedList), 1547 packed_list_([T1|Ts], Functor, Tag, List). 1548 1549% Functor and Tag are only for verifying that the terms are of the 1550% expected form. 1551packed_list_([], _, _, []). 1552packed_list_([T1|Ts], Functor, Tag, [X1|Xs]) :- 1553 detag(T1, Functor, Tag, X1, _, _), 1554 packed_list_(Ts, Functor, Tag, Xs). 1555 1556%! protobuf_field_is_map(+MessageType, +FieldName) is semidet. 1557% Succeeds if =MessageType='s =FieldName= is defined as a map<...> in 1558% the .proto file. 1559protobuf_field_is_map(MessageType0, FieldName) :- 1560 proto_meta_normalize(MessageType0, MessageType), 1561 proto_meta_field_name(MessageType, _, FieldName, FieldFqn), 1562 proto_meta_field_type(FieldFqn, 'TYPE_MESSAGE'), 1563 proto_meta_field_label(FieldFqn, 'LABEL_REPEATED'), 1564 proto_meta_field_type_name(FieldFqn, FieldTypeName), 1565 proto_meta_message_type_map_entry(FieldTypeName), 1566 assertion(proto_meta_field_name(FieldTypeName, 1, key, _)), 1567 assertion(proto_meta_field_name(FieldTypeName, 2, value, _)), 1568 !. 1569 1570%! protobuf_map_pairs(+ProtobufTermList:list, ?DictTag:atom, ?Pairs) is det. 1571% Convert between a list of protobuf map entries (in the form 1572% =|DictTag{key:Key, value:Value}|= and a key-value list as described 1573% in library(pairs). At least one of =ProtobufTermList= and =Pairs= 1574% must be instantiated; =DictTag= can be uninstantiated. If 1575% =ProtobufTermList= is from a term created by 1576% protobuf_parse_from_codes/3, the ordering of the items is undefined; 1577% you can order them by using keysort/2 (or by a predicate such as 1578% dict_pairs/3, list_to_assoc/2, or list_to_rbtree/2. 1579protobuf_map_pairs(ProtobufTermList, DictTag, Pairs) :- 1580 maplist(protobuf_dict_map_pairs(DictTag), ProtobufTermList, Pairs). 1581 1582protobuf_dict_map_pairs(DictTag, DictTag{key:Key,value:Value}, Key-Value)