diff options
author | Joshua Haberman <joshua@reverberate.org> | 2009-06-27 11:49:41 -0700 |
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committer | Joshua Haberman <joshua@reverberate.org> | 2009-06-27 11:49:41 -0700 |
commit | 3a67a1e9f95535adbc67f42771789cd83443a377 (patch) | |
tree | 086e67412cf2adc042e1aeaa2fc78d663fbed4b8 /upb_msg.h | |
parent | c7f2a271ae29066744cf09499f744a0c6b89a27e (diff) |
upb_msg constructor now more or less works.
Diffstat (limited to 'upb_msg.h')
-rw-r--r-- | upb_msg.h | 69 |
1 files changed, 49 insertions, 20 deletions
@@ -45,38 +45,67 @@ extern "C" { #endif +/* Forward declarations from descriptor.h. */ +struct google_protobuf_DescriptorProto; +struct google_protobuf_FieldDescriptorProto; + /* Structure definition. ******************************************************/ +/* Fields that reference other types have pointers to the other type. */ +union upb_msg_field_ref { + struct upb_msg *msg; /* Set if type == MESSAGE */ + struct upb_enum *_enum; /* Set if type == ENUM */ +}; + +/* Structure that describes a single field in a message. */ struct upb_msg_field { + struct google_protobuf_FieldDescriptorProto *descriptor; + uint32_t byte_offset; /* Where to find the data. */ + uint32_t field_index; /* Indexes upb_msg.fields. Also indicates set bit */ + union upb_msg_field_ref ref; +}; + +/* Structure that describes a single .proto message type. */ +struct upb_msg { + struct google_protobuf_DescriptorProto *descriptor; + size_t size; + uint32_t num_fields; + uint32_t set_flags_bytes; + uint32_t num_required_fields; /* Required fields have the lowest set bytemasks. */ + struct upb_inttable fields_by_num; + struct upb_strtable fields_by_name; + struct upb_msg_field *fields; +}; + +/* The num->field and name->field maps in upb_msg allow fast lookup of fields + * by number or name. These lookups are in the critical path of parsing and + * field lookup, so they must be as fast as possible. To make these more + * cache-friendly, we put the data in the table by value, but use only an + * abbreviated set of data (ie. not all the data in upb_msg_field). Notably, + * we don't include the pointer to the field descriptor. But the upb_msg_field + * can be retrieved in its entirety using the function below.*/ + +struct upb_abbrev_msg_field { uint32_t byte_offset; /* Where to find the data. */ uint32_t field_index:24; /* Indexes upb_msg.fields. Also indicates set bit */ upb_field_type_t type; /* Copied from descriptor for cache-friendliness. */ - union { - struct upb_msg *msg; /* Set if type == MESSAGE */ - struct upb_enum *_enum; /* Set if type == ENUM */ - } ref; + union upb_msg_field_ref ref; }; struct upb_fieldsbynum_entry { struct upb_inttable_entry e; - struct upb_msg_field f; + struct upb_abbrev_msg_field f; }; struct upb_fieldsbyname_entry { struct upb_strtable_entry e; - struct upb_msg_field f; + struct upb_abbrev_msg_field f; }; -struct upb_msg { - struct google_protobuf_DescriptorProto *descriptor; - size_t size; - int num_fields; - int set_flags_bytes; - int num_required_fields; /* Required fields have the lowest set bytemasks. */ - struct upb_inttable fields_by_num; - struct upb_strtable fields_by_name; - struct upb_msg_field *fields; -}; +struct upb_msg_field *upb_get_msg_field( + struct upb_abbrev_msg_field *f, struct upb_msg *m) { + return &m->fields[f->field_index]; +} /* Initialize and free a upb_msg. Caller retains ownership of d, but the msg * will contain references to it, so it must outlive the msg. Note that init @@ -87,14 +116,14 @@ void upb_msg_free(struct upb_msg *m); /* While these are written to be as fast as possible, it will still be faster * to cache the results of this lookup if possible. These return NULL if no * such field is found. */ -INLINE struct upb_msg_field *upb_msg_fieldbynum(struct upb_msg *m, - uint32_t number) { +INLINE struct upb_abbrev_msg_field *upb_msg_fieldbynum(struct upb_msg *m, + uint32_t number) { struct upb_fieldsbynum_entry *e = upb_inttable_lookup( &m->fields_by_num, number, sizeof(struct upb_fieldsbynum_entry)); return e ? &e->f : NULL; } -INLINE struct upb_msg_field *upb_msg_fieldbyname(struct upb_msg *m, - struct upb_string *name) { +INLINE struct upb_abbrev_msg_field *upb_msg_fieldbyname(struct upb_msg *m, + struct upb_string *name) { struct upb_fieldsbyname_entry *e = upb_strtable_lookup(&m->fields_by_name, name); return e ? &e->f : NULL; |