diff options
Diffstat (limited to 'src/upb_parse.h')
| -rw-r--r-- | src/upb_parse.h | 61 |
1 files changed, 32 insertions, 29 deletions
diff --git a/src/upb_parse.h b/src/upb_parse.h index 9e95c9c..dfcb534 100644 --- a/src/upb_parse.h +++ b/src/upb_parse.h @@ -21,33 +21,6 @@ extern "C" { #endif -/* Definitions. ***************************************************************/ - -/* A list of types as they are encoded on-the-wire. */ -enum upb_wire_type { - UPB_WIRE_TYPE_VARINT = 0, - UPB_WIRE_TYPE_64BIT = 1, - UPB_WIRE_TYPE_DELIMITED = 2, - UPB_WIRE_TYPE_START_GROUP = 3, - UPB_WIRE_TYPE_END_GROUP = 4, - UPB_WIRE_TYPE_32BIT = 5 -}; -typedef uint8_t upb_wire_type_t; - -/* A value as it is encoded on-the-wire, except delimited, which is handled - * separately. */ -union upb_wire_value { - uint64_t varint; - uint64_t _64bit; - uint32_t _32bit; -}; - -/* A tag occurs before each value on-the-wire. */ -struct upb_tag { - upb_field_number_t field_number; - upb_wire_type_t wire_type; -}; - INLINE bool upb_issubmsgtype(upb_field_type_t type) { return type == GOOGLE_PROTOBUF_FIELDDESCRIPTORPROTO_TYPE_GROUP || type == GOOGLE_PROTOBUF_FIELDDESCRIPTORPROTO_TYPE_MESSAGE; @@ -150,11 +123,16 @@ upb_status_t upb_parse_value(uint8_t *buf, uint8_t *end, upb_field_type_t ft, upb_status_t upb_parse_wire_value(uint8_t *buf, uint8_t *end, upb_wire_type_t wt, union upb_wire_value *wv, uint8_t **outbuf); -/* Low-level parsing functions. **********************************************/ +/* Functions to read wire values. *********************************************/ + +/* In general, these should never be called directly from any code outside upb. + * They are included here only because we expect them to get inlined inside the + * value-reading functions below. */ upb_status_t upb_get_v_uint64_t_full(uint8_t *buf, uint8_t *end, uint64_t *val, uint8_t **outbuf); +/* Gets a varint (wire type: UPB_WIRE_TYPE_VARINT). */ INLINE upb_status_t upb_get_v_uint64_t(uint8_t *buf, uint8_t *end, uint64_t *val, uint8_t **outbuf) { @@ -175,6 +153,7 @@ INLINE upb_status_t upb_get_v_uint64_t(uint8_t *buf, uint8_t *end, uint64_t *val } } +/* Gets a varint -- called when we only need 32 bits of it. */ INLINE upb_status_t upb_get_v_uint32_t(uint8_t *buf, uint8_t *end, uint32_t *val, uint8_t **outbuf) { @@ -185,6 +164,7 @@ INLINE upb_status_t upb_get_v_uint32_t(uint8_t *buf, uint8_t *end, return UPB_STATUS_OK; } +/* Gets a fixed-length 32-bit integer (wire type: UPB_WIRE_TYPE_32BIT). */ INLINE upb_status_t upb_get_f_uint32_t(uint8_t *buf, uint8_t *end, uint32_t *val, uint8_t **outbuf) { @@ -201,6 +181,7 @@ INLINE upb_status_t upb_get_f_uint32_t(uint8_t *buf, uint8_t *end, return UPB_STATUS_OK; } +/* Gets a fixed-length 64-bit integer (wire type: UPB_WIRE_TYPE_64BIT). */ INLINE upb_status_t upb_get_f_uint64_t(uint8_t *buf, uint8_t *end, uint64_t *val, uint8_t **outbuf) { @@ -218,15 +199,36 @@ INLINE upb_status_t upb_get_f_uint64_t(uint8_t *buf, uint8_t *end, return UPB_STATUS_OK; } +/* Functions to read .proto values. *******************************************/ + +/* These functions read the appropriate wire value for a given .proto type + * and then convert it based on the .proto type. These are the most efficient + * functions to call if you want to decode a value for a known type. */ + +/* Performs zig-zag decoding, which is used by sint32 and sint64. */ INLINE int32_t zz_decode_32(uint32_t n) { return (n >> 1) ^ -(int32_t)(n & 1); } INLINE int64_t zz_decode_64(uint64_t n) { return (n >> 1) ^ -(int64_t)(n & 1); } +/* Use macros to define a set of two functions for each .proto type: + * + * // Reads and converts a .proto value from buf, placing it in d. + * // "end" indicates the end of the current buffer (if the buffer does + * // not contain the entire value UPB_STATUS_NEED_MORE_DATA is returned). + * // On success, *outbuf will point to the first byte that was not consumed. + * upb_status_t upb_get_INT32(uint8_t *buf, uint8_t *end, int32_t *d, + * uint8_t **outbuf); + * + * // Given an already read wire value s (source), convert it to a .proto + * // value and store it in *d (destination). + * void upb_wvtov_INT32(uint32_t s, int32_t *d); + */ #define WVTOV(type, wire_t, val_t) \ INLINE void upb_wvtov_ ## type(wire_t s, val_t *d) #define GET(type, v_or_f, wire_t, val_t, member_name) \ - INLINE upb_status_t upb_get_ ## type(uint8_t *buf, uint8_t *end, val_t *d, uint8_t **outbuf) { \ + INLINE upb_status_t upb_get_ ## type(uint8_t *buf, uint8_t *end, val_t *d, \ + uint8_t **outbuf) { \ wire_t tmp; \ UPB_CHECK(upb_get_ ## v_or_f ## _ ## wire_t(buf, end, &tmp, outbuf)); \ upb_wvtov_ ## type(tmp, d); \ @@ -256,6 +258,7 @@ T(ENUM, v, uint32_t, int32_t, int32) { *d = (int32_t)s; } #undef GET #undef T +/* Parses a tag, places the result in *tag. */ INLINE upb_status_t parse_tag(uint8_t *buf, uint8_t *end, struct upb_tag *tag, uint8_t **outbuf) { |