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27 
28 #ifndef UPB_UTIL_REQUIRED_FIELDS_H_
29 #define UPB_UTIL_REQUIRED_FIELDS_H_
30 
31 #include "upb/reflection/def.h"
32 #include "upb/reflection/message.h"
33 
34 // Must be last.
35 #include "upb/port/def.inc"
36 
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40 
41 // A FieldPath can be encoded as an array of upb_FieldPathEntry, in the
42 // following format:
43 //    { {.field = f1}, {.field = f2} }                      # f1.f2
44 //    { {.field = f1}, {.index = 5}, {.field = f2} }        # f1[5].f2
45 //    { {.field = f1}, {.key = "abc"}, {.field = f2} }      # f1["abc"].f2
46 //
47 // Users must look at the type of `field` to know if an index or map key
48 // follows.
49 //
50 // A field path may be NULL-terminated, in which case a NULL field indicates
51 // the end of the field path.
52 typedef union {
53   const upb_FieldDef* field;
54   size_t array_index;
55   upb_MessageValue map_key;
56 } upb_FieldPathEntry;
57 
58 // Writes a string representing `*path` to `buf` in the following textual
59 // format:
60 //    foo.bar                    # Regular fields
61 //    repeated_baz[2].bar        # Repeated field
62 //    int32_msg_map[5].bar       # Integer-keyed map
63 //    string_msg_map["abc"]      # String-keyed map
64 //    bool_msg_map[true]         # Bool-keyed map
65 //
66 // The input array `*path` must be NULL-terminated.  The pointer `*path` will be
67 // updated to point to one past the terminating NULL pointer of the input array.
68 //
69 // The output buffer `buf` will always be NULL-terminated. If the output data
70 // (including NULL terminator) exceeds `size`, the result will be truncated.
71 // Returns the string length of the data we attempted to write, excluding the
72 // terminating NULL.
73 size_t upb_FieldPath_ToText(upb_FieldPathEntry** path, char* buf, size_t size);
74 
75 // Checks whether `msg` or any of its children has unset required fields,
76 // returning `true` if any are found.  `msg` may be NULL, in which case the
77 // message will be treated as empty.
78 //
79 // When this function returns true, `fields` is updated (if non-NULL) to point
80 // to a heap-allocated array encoding the field paths of the required fields
81 // that are missing.  Each path is terminated with {.field = NULL}, and a final
82 // {.field = NULL} terminates the list of paths.  The caller is responsible for
83 // freeing this array.
84 bool upb_util_HasUnsetRequired(const upb_Message* msg, const upb_MessageDef* m,
85                                const upb_DefPool* ext_pool,
86                                upb_FieldPathEntry** fields);
87 
88 #ifdef __cplusplus
89 } /* extern "C" */
90 #endif
91 
92 #include "upb/port/undef.inc"
93 
94 #endif /* UPB_UTIL_REQUIRED_FIELDS_H_ */
95