mini_descriptor/internal/encode.h

0001 // Protocol Buffers - Google's data interchange format
0002 // Copyright 2023 Google LLC.  All rights reserved.
0003 //
0004 // Use of this source code is governed by a BSD-style
0005 // license that can be found in the LICENSE file or at
0006 // https://developers.google.com/open-source/licenses/bsd
0007
0008 #ifndef UPB_MINI_DESCRIPTOR_INTERNAL_ENCODE_H_
0009 #define UPB_MINI_DESCRIPTOR_INTERNAL_ENCODE_H_
0010
0011 #include <stdint.h>
0012
0013 #include "upb/base/descriptor_constants.h"
0014
0015 // Must be last.
0016 #include "upb/port/def.inc"
0017
0018 // If the input buffer has at least this many bytes available, the encoder call
0019 // is guaranteed to succeed (as long as field number order is maintained).
0020 #define kUpb_MtDataEncoder_MinSize 16
0021
0022 typedef struct {
0023   char* end;  // Limit of the buffer passed as a parameter.
0024   // Aliased to internal-only members in .cc.
0025   char internal[32];
0026 } upb_MtDataEncoder;
0027
0028 #ifdef __cplusplus
0029 extern "C" {
0030 #endif
0031
0032 // Encodes field/oneof information for a given message.  The sequence of calls
0033 // should look like:
0034 //
0035 //   upb_MtDataEncoder e;
0036 //   char buf[256];
0037 //   char* ptr = buf;
0038 //   e.end = ptr + sizeof(buf);
0039 //   unit64_t msg_mod = ...; // bitwise & of kUpb_MessageModifiers or zero
0040 //   ptr = upb_MtDataEncoder_StartMessage(&e, ptr, msg_mod);
0041 //   // Fields *must* be in field number order.
0042 //   ptr = upb_MtDataEncoder_PutField(&e, ptr, ...);
0043 //   ptr = upb_MtDataEncoder_PutField(&e, ptr, ...);
0044 //   ptr = upb_MtDataEncoder_PutField(&e, ptr, ...);
0045 //
0046 //   // If oneofs are present.  Oneofs must be encoded after regular fields.
0047 //   ptr = upb_MiniTable_StartOneof(&e, ptr)
0048 //   ptr = upb_MiniTable_PutOneofField(&e, ptr, ...);
0049 //   ptr = upb_MiniTable_PutOneofField(&e, ptr, ...);
0050 //
0051 //   ptr = upb_MiniTable_StartOneof(&e, ptr);
0052 //   ptr = upb_MiniTable_PutOneofField(&e, ptr, ...);
0053 //   ptr = upb_MiniTable_PutOneofField(&e, ptr, ...);
0054 //
0055 // Oneofs must be encoded after all regular fields.
0056 char* upb_MtDataEncoder_StartMessage(upb_MtDataEncoder* e, char* ptr,
0057                                      uint64_t msg_mod);
0058 char* upb_MtDataEncoder_PutField(upb_MtDataEncoder* e, char* ptr,
0059                                  upb_FieldType type, uint32_t field_num,
0060                                  uint64_t field_mod);
0061 char* upb_MtDataEncoder_StartOneof(upb_MtDataEncoder* e, char* ptr);
0062 char* upb_MtDataEncoder_PutOneofField(upb_MtDataEncoder* e, char* ptr,
0063                                       uint32_t field_num);
0064
0065 // Encodes the set of values for a given enum. The values must be given in
0066 // order (after casting to uint32_t), and repeats are not allowed.
0067 char* upb_MtDataEncoder_StartEnum(upb_MtDataEncoder* e, char* ptr);
0068 char* upb_MtDataEncoder_PutEnumValue(upb_MtDataEncoder* e, char* ptr,
0069                                      uint32_t val);
0070 char* upb_MtDataEncoder_EndEnum(upb_MtDataEncoder* e, char* ptr);
0071
0072 // Encodes an entire mini descriptor for an extension.
0073 char* upb_MtDataEncoder_EncodeExtension(upb_MtDataEncoder* e, char* ptr,
0074                                         upb_FieldType type, uint32_t field_num,
0075                                         uint64_t field_mod);
0076
0077 // Encodes an entire mini descriptor for a map.
0078 char* upb_MtDataEncoder_EncodeMap(upb_MtDataEncoder* e, char* ptr,
0079                                   upb_FieldType key_type,
0080                                   upb_FieldType value_type, uint64_t key_mod,
0081                                   uint64_t value_mod);
0082
0083 // Encodes an entire mini descriptor for a message set.
0084 char* upb_MtDataEncoder_EncodeMessageSet(upb_MtDataEncoder* e, char* ptr);
0085
0086 #ifdef __cplusplus
0087 } /* extern "C" */
0088 #endif
0089
0090 #include "upb/port/undef.inc"
0091
0092 #endif /* UPB_MINI_DESCRIPTOR_INTERNAL_ENCODE_H_ */