xref: /aosp_15_r20/external/grpc-grpc/third_party/upb/upb/message/promote.h (revision cc02d7e222339f7a4f6ba5f422e6413f4bd931f2)
1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2023 Google LLC.  All rights reserved.
3 //
4 // Use of this source code is governed by a BSD-style
5 // license that can be found in the LICENSE file or at
6 // https://developers.google.com/open-source/licenses/bsd
7 
8 #ifndef UPB_MESSAGE_PROMOTE_H_
9 #define UPB_MESSAGE_PROMOTE_H_
10 
11 #include "upb/message/array.h"
12 #include "upb/message/internal/extension.h"
13 #include "upb/message/map.h"
14 #include "upb/wire/decode.h"
15 
16 // Must be last.
17 #include "upb/port/def.inc"
18 
19 #ifdef __cplusplus
20 extern "C" {
21 #endif
22 
23 typedef enum {
24   kUpb_GetExtension_Ok,
25   kUpb_GetExtension_NotPresent,
26   kUpb_GetExtension_ParseError,
27   kUpb_GetExtension_OutOfMemory,
28 } upb_GetExtension_Status;
29 
30 typedef enum {
31   kUpb_GetExtensionAsBytes_Ok,
32   kUpb_GetExtensionAsBytes_NotPresent,
33   kUpb_GetExtensionAsBytes_EncodeError,
34 } upb_GetExtensionAsBytes_Status;
35 
36 // Returns a message value or promotes an unknown field to an extension.
37 //
38 // TODO: Only supports extension fields that are messages,
39 // expand support to include non-message types.
40 upb_GetExtension_Status upb_Message_GetOrPromoteExtension(
41     upb_Message* msg, const upb_MiniTableExtension* ext_table,
42     int decode_options, upb_Arena* arena, upb_MessageValue* value);
43 
44 typedef enum {
45   kUpb_FindUnknown_Ok,
46   kUpb_FindUnknown_NotPresent,
47   kUpb_FindUnknown_ParseError,
48 } upb_FindUnknown_Status;
49 
50 typedef struct {
51   upb_FindUnknown_Status status;
52   // Start of unknown field data in message arena.
53   const char* ptr;
54   // Size of unknown field data.
55   size_t len;
56 } upb_FindUnknownRet;
57 
58 // Finds first occurrence of unknown data by tag id in message.
59 // A depth_limit of zero means to just use the upb default depth limit.
60 upb_FindUnknownRet upb_Message_FindUnknown(const upb_Message* msg,
61                                            uint32_t field_number,
62                                            int depth_limit);
63 
64 typedef enum {
65   kUpb_UnknownToMessage_Ok,
66   kUpb_UnknownToMessage_ParseError,
67   kUpb_UnknownToMessage_OutOfMemory,
68   kUpb_UnknownToMessage_NotFound,
69 } upb_UnknownToMessage_Status;
70 
71 typedef struct {
72   upb_UnknownToMessage_Status status;
73   upb_Message* message;
74 } upb_UnknownToMessageRet;
75 
76 // Promotes an "empty" non-repeated message field in `parent` to a message of
77 // the correct type.
78 //
79 // Preconditions:
80 //
81 // 1. The message field must currently be in the "empty" state (this must have
82 //    been previously verified by the caller by calling
83 //    `upb_Message_GetTaggedMessagePtr()` and observing that the message is
84 //    indeed empty).
85 //
86 // 2. This `field` must have previously been linked.
87 //
88 // If the promotion succeeds, `parent` will have its data for `field` replaced
89 // by the promoted message, which is also returned in `*promoted`.  If the
90 // return value indicates an error status, `parent` and `promoted` are
91 // unchanged.
92 upb_DecodeStatus upb_Message_PromoteMessage(upb_Message* parent,
93                                             const upb_MiniTable* mini_table,
94                                             const upb_MiniTableField* field,
95                                             int decode_options,
96                                             upb_Arena* arena,
97                                             upb_Message** promoted);
98 
99 // Promotes any "empty" messages in this array to a message of the correct type
100 // `mini_table`.  This function should only be called for arrays of messages.
101 //
102 // If the return value indicates an error status, some but not all elements may
103 // have been promoted, but the array itself will not be corrupted.
104 upb_DecodeStatus upb_Array_PromoteMessages(upb_Array* arr,
105                                            const upb_MiniTable* mini_table,
106                                            int decode_options,
107                                            upb_Arena* arena);
108 
109 // Promotes any "empty" entries in this map to a message of the correct type
110 // `mini_table`.  This function should only be called for maps that have a
111 // message type as the map value.
112 //
113 // If the return value indicates an error status, some but not all elements may
114 // have been promoted, but the map itself will not be corrupted.
115 upb_DecodeStatus upb_Map_PromoteMessages(upb_Map* map,
116                                          const upb_MiniTable* mini_table,
117                                          int decode_options, upb_Arena* arena);
118 
119 ////////////////////////////////////////////////////////////////////////////////
120 // OLD promotion interfaces, will be removed!
121 ////////////////////////////////////////////////////////////////////////////////
122 
123 // Promotes unknown data inside message to a upb_Message parsing the unknown.
124 //
125 // The unknown data is removed from message after field value is set
126 // using upb_Message_SetMessage.
127 //
128 // WARNING!: See b/267655898
129 upb_UnknownToMessageRet upb_MiniTable_PromoteUnknownToMessage(
130     upb_Message* msg, const upb_MiniTable* mini_table,
131     const upb_MiniTableField* field, const upb_MiniTable* sub_mini_table,
132     int decode_options, upb_Arena* arena);
133 
134 // Promotes all unknown data that matches field tag id to repeated messages
135 // in upb_Array.
136 //
137 // The unknown data is removed from message after upb_Array is populated.
138 // Since repeated messages can't be packed we remove each unknown that
139 // contains the target tag id.
140 upb_UnknownToMessage_Status upb_MiniTable_PromoteUnknownToMessageArray(
141     upb_Message* msg, const upb_MiniTableField* field,
142     const upb_MiniTable* mini_table, int decode_options, upb_Arena* arena);
143 
144 // Promotes all unknown data that matches field tag id to upb_Map.
145 //
146 // The unknown data is removed from message after upb_Map is populated.
147 // Since repeated messages can't be packed we remove each unknown that
148 // contains the target tag id.
149 upb_UnknownToMessage_Status upb_MiniTable_PromoteUnknownToMap(
150     upb_Message* msg, const upb_MiniTable* mini_table,
151     const upb_MiniTableField* field, int decode_options, upb_Arena* arena);
152 
153 #ifdef __cplusplus
154 } /* extern "C" */
155 #endif
156 
157 #include "upb/port/undef.inc"
158 
159 #endif  // UPB_MESSAGE_PROMOTE_H_
160