diff options
author | Petteri Aimonen <jpa@git.mail.kapsi.fi> | 2013-07-17 01:06:54 +0400 |
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committer | Petteri Aimonen <jpa@git.mail.kapsi.fi> | 2013-07-17 01:06:54 +0400 |
commit | 7c5e184c261bd5f5652993232f2125a6802004ab (patch) | |
tree | 4807060c48b1b88c302a75f34a70ff729939491d /pb.h | |
parent | f064c2c48a43b0c1b011d52f53d519d809b8cee7 (diff) |
Implement generator support for extension fields (no encoder/decoder support yet)
Diffstat (limited to 'pb.h')
-rw-r--r-- | pb.h | 55 |
1 files changed, 53 insertions, 2 deletions
@@ -148,8 +148,12 @@ typedef uint8_t pb_type_t; * submsg_fields is pointer to field descriptions */ #define PB_LTYPE_SUBMESSAGE 0x06 +/* Extension pseudo-field + * The field contains a pointer to pb_extension_t */ +#define PB_LTYPE_EXTENSION 0x07 + /* Number of declared LTYPES */ -#define PB_LTYPES_COUNT 7 +#define PB_LTYPES_COUNT 8 #define PB_LTYPE_MASK 0x0F /**** Field repetition rules ****/ @@ -270,6 +274,51 @@ typedef enum { PB_WT_32BIT = 5 } pb_wire_type_t; +/* Structure for defining the handling of unknown/extension fields. + * Usually the pb_extension_type_t structure is automatically generated, + * while the pb_extension_t structure is created by the user. However, + * if you want to catch all unknown fields, you can also create a custom + * pb_extension_type_t with your own callback. + */ +typedef struct _pb_extension_type_t pb_extension_type_t; +typedef struct _pb_extension_t pb_extension_t; +struct _pb_extension_type_t { + /* Called for each unknown field in the message. + * If you handle the field, read off all of its data and return true. + * If you do not handle the field, do not read anything and return true. + * If you run into an error, return false. + * Set to NULL for default handler. + */ + bool (*decode)(pb_istream_t *stream, pb_extension_t *extension, + uint32_t tag, pb_wire_type_t wire_type); + + /* Called once after all regular fields have been encoded. + * If you have something to write, do so and return true. + * If you do not have anything to write, just return true. + * If you run into an error, return false. + * Set to NULL for default handler. + */ + bool (*encode)(pb_ostream_t *stream, pb_extension_t *extension); + + /* Free field for use by the callback. */ + const void *arg; +}; + +struct _pb_extension_t { + /* Type describing the extension field. Usually you'll initialize + * this to a pointer to the automatically generated structure. */ + const pb_extension_type_t *type; + + /* Destination for the decoded data. This must match the datatype + * of the extension field. */ + void *dest; + + /* Pointer to the next extension handler, or NULL. + * If this extension does not match a field, the next handler is + * automatically called. */ + pb_extension_t *next; +}; + /* 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])) @@ -333,13 +382,14 @@ typedef enum { #define PB_LTYPE_MAP_STRING PB_LTYPE_STRING #define PB_LTYPE_MAP_UINT32 PB_LTYPE_VARINT #define PB_LTYPE_MAP_UINT64 PB_LTYPE_VARINT +#define PB_LTYPE_MAP_EXTENSION PB_LTYPE_EXTENSION /* This is the actual macro used in field descriptions. * It takes these arguments: * - Field tag number * - Field type: BOOL, BYTES, DOUBLE, ENUM, FIXED32, FIXED64, * FLOAT, INT32, INT64, MESSAGE, SFIXED32, SFIXED64 - * SINT32, SINT64, STRING, UINT32 or UINT64 + * SINT32, SINT64, STRING, UINT32, UINT64 or EXTENSION * - Field rules: REQUIRED, OPTIONAL or REPEATED * - Allocation: STATIC or CALLBACK * - Message name @@ -352,6 +402,7 @@ typedef enum { PB_ ## rules ## _ ## allocation(tag, message, field, prevfield, \ PB_LTYPE_MAP_ ## type, ptr) + /* These macros are used for giving out error messages. * They are mostly a debugging aid; the main error information * is the true/false return value from functions. |