decode_fast.h

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// These are the specialized field parser functions for the fast parser.
// Generated tables will refer to these by name.
//
// The function names are encoded with names like:
//
//   //  123 4
//   upb_pss_1bt();   // Parse singular string, 1 byte tag.
//
// In position 1:
//   - 'p' for parse, most function use this
//   - 'c' for copy, for when we are copying strings instead of aliasing
//
// In position 2 (cardinality):
//   - 's' for singular, with or without hasbit
//   - 'o' for oneof
//   - 'r' for non-packed repeated
//   - 'p' for packed repeated
//
// In position 3 (type):
//   - 'b1' for bool
//   - 'v4' for 4-byte varint
//   - 'v8' for 8-byte varint
//   - 'z4' for zig-zag-encoded 4-byte varint
//   - 'z8' for zig-zag-encoded 8-byte varint
//   - 'f4' for 4-byte fixed
//   - 'f8' for 8-byte fixed
//   - 'm' for sub-message
//   - 's' for string (validate UTF-8)
//   - 'b' for bytes
//
// In position 4 (tag length):
//   - '1' for one-byte tags (field numbers 1-15)
//   - '2' for two-byte tags (field numbers 16-2048)
 
#ifndef UPB_DECODE_FAST_H_
#define UPB_DECODE_FAST_H_
 
#include "upb/msg.h"
 
struct upb_Decoder;
 
// The fallback, generic parsing function that can handle any field type.
// This just uses the regular (non-fast) parser to parse a single field.
const char* fastdecode_generic(struct upb_Decoder* d, const char* ptr,
                               upb_Message* msg, intptr_t table,
                               uint64_t hasbits, uint64_t data);
 
#define UPB_PARSE_PARAMS                                                    \
  struct upb_Decoder *d, const char *ptr, upb_Message *msg, intptr_t table, \
      uint64_t hasbits, uint64_t data
 
/* primitive fields ***********************************************************/
 
#define F(card, type, valbytes, tagbytes) \
  const char* upb_p##card##type##valbytes##_##tagbytes##bt(UPB_PARSE_PARAMS);
 
#define TYPES(card, tagbytes) \
  F(card, b, 1, tagbytes)     \
  F(card, v, 4, tagbytes)     \
  F(card, v, 8, tagbytes)     \
  F(card, z, 4, tagbytes)     \
  F(card, z, 8, tagbytes)     \
  F(card, f, 4, tagbytes)     \
  F(card, f, 8, tagbytes)
 
#define TAGBYTES(card) \
  TYPES(card, 1)       \
  TYPES(card, 2)
 
TAGBYTES(s)
TAGBYTES(o)
TAGBYTES(r)
TAGBYTES(p)
 
#undef F
#undef TYPES
#undef TAGBYTES
 
/* string fields **************************************************************/
 
#define F(card, tagbytes, type)                                     \
  const char* upb_p##card##type##_##tagbytes##bt(UPB_PARSE_PARAMS); \
  const char* upb_c##card##type##_##tagbytes##bt(UPB_PARSE_PARAMS);
 
#define UTF8(card, tagbytes) \
  F(card, tagbytes, s)       \
  F(card, tagbytes, b)
 
#define TAGBYTES(card) \
  UTF8(card, 1)        \
  UTF8(card, 2)
 
TAGBYTES(s)
TAGBYTES(o)
TAGBYTES(r)
 
#undef F
#undef TAGBYTES
 
/* sub-message fields *********************************************************/
 
#define F(card, tagbytes, size_ceil, ceil_arg) \
  const char* upb_p##card##m_##tagbytes##bt_max##size_ceil##b(UPB_PARSE_PARAMS);
 
#define SIZES(card, tagbytes) \
  F(card, tagbytes, 64, 64)   \
  F(card, tagbytes, 128, 128) \
  F(card, tagbytes, 192, 192) \
  F(card, tagbytes, 256, 256) \
  F(card, tagbytes, max, -1)
 
#define TAGBYTES(card) \
  SIZES(card, 1)       \
  SIZES(card, 2)
 
TAGBYTES(s)
TAGBYTES(o)
TAGBYTES(r)
 
#undef TAGBYTES
#undef SIZES
#undef F
 
#undef UPB_PARSE_PARAMS
 
#endif /* UPB_DECODE_FAST_H_ */