Example

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

diff --git a/pb.h b/pb.h
index 1d32ee9..2c6a252 100644 (file)
--- a/pb.h
+++ b/pb.h
@@ -1,6 +1,11 @@
 #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 <stdint.h>
 #include <stddef.h>
 #include <stdbool.h>
@@ -12,15 +17,7 @@
 #define pb_packed
 #endif
 
-/* 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;
-
-/* 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.
  * 
@@ -129,6 +126,8 @@ typedef struct {
  * 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;
@@ -143,10 +142,19 @@ struct _pb_callback_t {
     void *arg;
 };
 
+/* 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}