Merge branch 'dev-0.2'

[apps/agl-service-can-low-level.git] / pb_decode.h

diff --git a/pb_decode.h b/pb_decode.h
index 7045c5d..35de0a2 100644 (file)
--- a/pb_decode.h
+++ b/pb_decode.h
@@ -3,7 +3,7 @@
 
 /* pb_decode.h: Functions to decode protocol buffers. Depends on pb_decode.c.
  * The main function is pb_decode. You will also need to create an input
- * stream, which is easiest to do with pb_istream_t.
+ * stream, which is easiest to do with pb_istream_from_buffer().
  * 
  * You also need structures and their corresponding pb_field_t descriptions.
  * These are usually generated from .proto-files with a script.
@@ -12,6 +12,10 @@
 #include <stdbool.h>
 #include "pb.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* Lightweight input stream.
  * You can provide a callback function for reading or use
  * pb_istream_from_buffer.
@@ -19,20 +23,31 @@
  * Rules for callback:
  * 1) Return false on IO errors. This will cause decoding to abort.
  * 
- * 2) If buf is NULL, read but don't store bytes ("skip input").
- * 
- * 3) You can use state to store your own data (e.g. buffer pointer),
+ * 2) 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.
  * 
- * 4) Your callback may be used with substreams, in which case bytes_left
+ * 3) Your callback may be used with substreams, in which case bytes_left
  * is different than from the main stream. Don't use bytes_left to compute
  * any pointers.
  */
 struct _pb_istream_t
 {
+#ifdef PB_BUFFER_ONLY
+    /* Callback pointer is not used in buffer-only configuration.
+     * Having an int pointer here allows binary compatibility but
+     * gives an error if someone tries to assign callback function.
+     */
+    int *callback;
+#else
     bool (*callback)(pb_istream_t *stream, uint8_t *buf, size_t count);
+#endif
+
     void *state; /* Free field for use by callback implementation */
     size_t bytes_left;
+    
+#ifndef PB_NO_ERRMSG
+    const char *errmsg;
+#endif
 };
 
 pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize);
@@ -44,24 +59,49 @@ bool pb_read(pb_istream_t *stream, uint8_t *buf, size_t count);
  */
 bool pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct);
 
+/* Same as pb_decode, except does not initialize the destination structure
+ * to default values. This is slightly faster if you need no default values
+ * and just do memset(struct, 0, sizeof(struct)) yourself.
+ */
+bool pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct);
+
 /* --- Helper functions ---
  * You may want to use these from your caller or callbacks.
  */
 
+/* Decode the tag for the next field in the stream. Gives the wire type and
+ * field tag. At end of the message, returns false and sets eof to true. */
 bool pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof);
+
+/* Skip the field payload data, given the wire type. */
 bool pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type);
 
+/* Decode an integer in the varint format. This works for bool, enum, int32,
+ * int64, uint32 and uint64 field types. */
 bool pb_decode_varint(pb_istream_t *stream, uint64_t *dest);
 
-bool pb_skip_varint(pb_istream_t *stream);
-bool pb_skip_string(pb_istream_t *stream);
+/* Decode an integer in the zig-zagged svarint format. This works for sint32
+ * and sint64. */
+bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest);
+
+/* Decode a fixed32, sfixed32 or float value. You need to pass a pointer to
+ * a 4-byte wide C variable. */
+bool pb_decode_fixed32(pb_istream_t *stream, void *dest);
+
+/* Decode a fixed64, sfixed64 or double value. You need to pass a pointer to
+ * a 8-byte wide C variable. */
+bool pb_decode_fixed64(pb_istream_t *stream, void *dest);
 
-/* --- Field decoders ---
- * Each decoder takes stream and field description, and a pointer to the field
- * in the destination struct (dest = struct_addr + field->data_offset).
- * For arrays, these functions are called repeatedly.
+/* Make a limited-length substream for reading a PB_WT_STRING field. */
+bool pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream);
+void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream);
+
+/* --- Internal functions ---
+ * These functions are not terribly useful for the average library user, but
+ * are exported to make the unit testing and extending nanopb easier.
  */
 
+#ifdef NANOPB_INTERNALS
 bool pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest);
 bool pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
 bool pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
@@ -71,4 +111,12 @@ bool pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
 bool pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
 bool pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest);
 
+bool pb_skip_varint(pb_istream_t *stream);
+bool pb_skip_string(pb_istream_t *stream);
+#endif
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
 #endif