X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=pb.h;h=ea94efc58540c4abb86c5873c9ae84937c7377bd;hb=a3f5e4d81f8d81e208f33dded6d892fbbdce90bc;hp=99e4bf7ee97d06d26babb150ec910e82f32410b8;hpb=84304b343a4b06a7918bc80ab45f08d1cae0b9cb;p=apps%2Fagl-service-can-low-level.git diff --git a/pb.h b/pb.h index 99e4bf7e..ea94efc5 100644 --- a/pb.h +++ b/pb.h @@ -1,60 +1,23 @@ #ifndef _PB_H_ #define _PB_H_ +/* pb.h: Common parts for nanopb library. + * Most of these are quite low-level stuff. For the high-level interface, + * see pb_encode.h or pb_decode.h + */ + #include -#include // size_t +#include #include #ifdef __GNUC__ -// This just reduces memory requirements, but is not required. +/* This just reduces memory requirements, but is not required. */ #define pb_packed __attribute__((packed)) #else #define pb_packed #endif -/* Lightweight input stream. - * If buf is NULL, read but don't store bytes. - * You have to provide a callback function for reading. - * You can use state to store your own data (e.g. buffer pointer), - * and rely on pb_read to verify that no-body reads past bytes_left. - * However, substreams may change bytes_left so don't use that to - * compute any pointers. - */ -typedef struct _pb_istream_t pb_istream_t; -struct _pb_istream_t -{ - bool (*callback)(pb_istream_t *stream, uint8_t *buf, size_t count); - void *state; // Free field for use by callback implementation - size_t bytes_left; -}; - -static inline bool pb_read(pb_istream_t *stream, uint8_t *buf, size_t count) -{ - if (stream->bytes_left < count) - return false; - - bool status = stream->callback(stream, buf, count); - stream->bytes_left -= count; - return status; -} - -/* Lightweight output stream. */ -typedef struct _pb_ostream_t pb_ostream_t; -struct _pb_ostream_t -{ - bool (*callback)(pb_ostream_t *stream, const uint8_t *buf, size_t count); - void *state; // Free field for use by callback implementation - size_t bytes_written; -}; - -static inline bool pb_write(pb_ostream_t *stream, const uint8_t *buf, size_t count) -{ - bool status = stream->callback(stream, buf, count); - stream->bytes_written += count; - return status; -} - -/* List of possible field types +/* List of possible field types. These are used in the autogenerated code. * Least-significant 4 bits tell the scalar type * Most-significant 4 bits specify repeated/required/packed etc. * @@ -65,53 +28,53 @@ static inline bool pb_write(pb_ostream_t *stream, const uint8_t *buf, size_t cou */ typedef enum { - // Standard integer types - PB_LTYPE_UINT32 = 0x00, - PB_LTYPE_INT32 = 0x00, - PB_LTYPE_SINT32 = 0x01, - PB_LTYPE_FIXED32 = 0x02, - PB_LTYPE_SFIXED32 = 0x02, - PB_LTYPE_UINT64 = 0x03, - PB_LTYPE_INT64 = 0x03, - PB_LTYPE_SINT64 = 0x04, - PB_LTYPE_FIXED64 = 0x05, - PB_LTYPE_SFIXED64 = 0x05, - PB_LTYPE_BOOL = 0x06, - PB_LTYPE_ENUM = 0x07, + /************************ + * Field contents types * + ************************/ + + /* Numeric types */ + PB_LTYPE_VARINT = 0x00, /* int32, uint32, int64, uint64, bool, enum */ + PB_LTYPE_SVARINT = 0x01, /* sint32, sint64 */ + PB_LTYPE_FIXED32 = 0x02, /* fixed32, sfixed32, float */ + PB_LTYPE_FIXED64 = 0x03, /* fixed64, sfixed64, double */ + + /* Marker for last packable field type. */ + PB_LTYPE_LAST_PACKABLE = 0x03, - // Standard float types - PB_LTYPE_FLOAT = 0x08, - PB_LTYPE_DOUBLE = 0x09, + /* Byte array with pre-allocated buffer. + * data_size is the length of the allocated PB_BYTES_ARRAY structure. */ + PB_LTYPE_BYTES = 0x04, - // Byte array with pre-allocated buffer. - // data_size is the length of the allocated PB_BYTES_ARRAY structure. - PB_LTYPE_BYTES = 0x0A, + /* String with pre-allocated buffer. + * data_size is the maximum length. */ + PB_LTYPE_STRING = 0x05, - // String with pre-allocated buffer. - // data_size is the maximum length. - PB_LTYPE_STRING = 0x0B, + /* Submessage + * submsg_fields is pointer to field descriptions */ + PB_LTYPE_SUBMESSAGE = 0x06, - // Submessage - // submsg_fields is pointer to field descriptions - PB_LTYPE_SUBMESSAGE = 0x0C, + /* Number of declared LTYPES */ + PB_LTYPES_COUNT = 7, - ///////////// - // Modifier flags + /****************** + * Modifier flags * + ******************/ - // Just the basic, write data at data_offset + /* Just the basic, write data at data_offset */ PB_HTYPE_REQUIRED = 0x00, - // Write true at size_offset + /* Write true at size_offset */ PB_HTYPE_OPTIONAL = 0x10, - // Read to pre-allocated array - // Maximum number of entries is array_size, - // actual number is stored at size_offset + /* Read to pre-allocated array + * Maximum number of entries is array_size, + * actual number is stored at size_offset */ PB_HTYPE_ARRAY = 0x20, - // Works for all required/optional/repeated fields. - // data_offset points to pb_callback_t structure. - // LTYPE is ignored. + /* Works for all required/optional/repeated fields. + * data_offset points to pb_callback_t structure. + * LTYPE should be 0 (it is ignored, but sometimes + * used to speculatively index an array). */ PB_HTYPE_CALLBACK = 0x30 } pb_packed pb_type_t; @@ -129,51 +92,71 @@ typedef struct _pb_field_t pb_field_t; struct _pb_field_t { uint8_t tag; pb_type_t type; - uint8_t data_offset; // Offset of actual data or array start - uint8_t size_offset; // Offset of array size or has-boolean - uint8_t data_size; // Data size in bytes for a single item - uint8_t array_size; // Maximum number of entries in array + uint8_t data_offset; /* Offset of field data, relative to previous field. */ + int8_t size_offset; /* Offset of array size or has-boolean, relative to data */ + uint8_t data_size; /* Data size in bytes for a single item */ + uint8_t array_size; /* Maximum number of entries in array */ - // Field definitions for submessage - // OR default value for all other non-array, non-callback types - // If null, then field will zeroed. + /* Field definitions for submessage + * OR default value for all other non-array, non-callback types + * If null, then field will zeroed. */ const void *ptr; } pb_packed; -#define PB_LAST_FIELD {0,0,0,0} - -// This structure is used for 'bytes' arrays. -// It has the number of bytes in the beginning, and after that an array. -#define PB_BYTES_ARRAY(buffersize) \ -struct { \ - size_t size; \ - uint8_t bytes[buffersize]; \ -} - -typedef PB_BYTES_ARRAY(1) pb_bytes_array_t; +/* This structure is used for 'bytes' arrays. + * It has the number of bytes in the beginning, and after that an array. + * Note that actual structs used will have a different length of bytes array. + */ +typedef struct { + size_t size; + uint8_t bytes[1]; +} pb_bytes_array_t; -// This structure is used for giving the callback function. -// -// The decoding callback will be given a limited-length stream -// If the wire type was string, the length is the length of the string. -// If the wire type was a varint/fixed32/fixed64, the length is the length -// of the actual value. -// The function may be called multiple times (especially for repeated types, -// but also otherwise if the message happens to contain the field multiple -// times.) -// -// The encoding callback will receive the actual output stream. -// It should write all the data in one call, including the field tag and -// wire type. It can write multiple fields. +/* This structure is used for giving the callback function. + * It is stored in the message structure and filled in by the method that + * calls pb_decode. + * + * The decoding callback will be given a limited-length stream + * If the wire type was string, the length is the length of the string. + * If the wire type was a varint/fixed32/fixed64, the length is the length + * of the actual value. + * The function may be called multiple times (especially for repeated types, + * but also otherwise if the message happens to contain the field multiple + * times.) + * + * The encoding callback will receive the actual output stream. + * It should write all the data in one call, including the field tag and + * wire type. It can write multiple fields. + * + * The callback can be null if you want to skip a field. + */ +typedef struct _pb_istream_t pb_istream_t; +typedef struct _pb_ostream_t pb_ostream_t; typedef struct _pb_callback_t pb_callback_t; struct _pb_callback_t { union { bool (*decode)(pb_istream_t *stream, const pb_field_t *field, void *arg); - bool (*encode)(pb_ostream_t *stream, const pb_field_t *field, void *arg); + bool (*encode)(pb_ostream_t *stream, const pb_field_t *field, const void *arg); } funcs; - // Free arg for use by callback + /* Free arg for use by callback */ void *arg; }; -#endif \ No newline at end of file +/* Wire types. Library user needs these only in encoder callbacks. */ +typedef enum { + PB_WT_VARINT = 0, + PB_WT_64BIT = 1, + PB_WT_STRING = 2, + PB_WT_32BIT = 5 +} pb_wire_type_t; + +/* These macros are used to declare pb_field_t's in the constant array. */ +#define pb_membersize(st, m) (sizeof ((st*)0)->m) +#define pb_arraysize(st, m) (pb_membersize(st, m) / pb_membersize(st, m[0])) +#define pb_delta(st, m1, m2) ((int)offsetof(st, m1) - (int)offsetof(st, m2)) +#define pb_delta_end(st, m1, m2) (offsetof(st, m1) - offsetof(st, m2) - pb_membersize(st, m2)) +#define PB_LAST_FIELD {0,0,0,0} + + +#endif