Created a CHANGELOG file for easy reference.

Compile the generated files with the same extra-strict
settings as the core, in order to detect problems in tests.

Update issue 32
Status: FixedInGit

CHANGELOG

@@ -0,0 +1,37 @@
+nanopb-0.1.6
+ Reorganize the field decoder interface (issue 2)
+ Improve performance in submessage decoding (issue 28)
+ Implement error messages in the decoder side (issue 7)
+ Extended testcases (alltypes test is now complete).
+ Fix some compiler warnings (issues 25, 26, 27, 32).
+
+nanopb-0.1.5
+ Fix bug in decoder with packed arrays (issue 23).
+ Extended testcases.
+ Fix some compiler warnings.
+
+nanopb-0.1.4
+ Add compile-time options for easy-to-use >255 field support.
+ Improve the detection of missing required fields.
+ Added example on how to handle union messages.
+ Fix generator error with .proto without messages.
+ Fix problems that stopped the code from compiling with some compilers.
+ Fix some compiler warnings.
+
+nanopb-0.1.3
+ Refactor the field encoder interface.
+ Improve generator error messages (issue 5)
+ Add descriptor.proto into the #include exclusion list
+ Fix some compiler warnings.
+
+nanopb-0.1.2
+ Make the generator to generate include for other .proto files (issue 4).
+ Fixed generator not working on Windows (issue 3)
+
+nanopb-0.1.1
+ Fixed bug in encoder with 'bytes' fields (issue 1).
+ Fixed a bug in the generator that caused a compiler error on sfixed32 and sfixed64 fields.
+ Extended testcases.
+
+nanopb-0.1.0
+ First stable release.

README

@@ -5,5 +5,7 @@ Homepage: http://kapsi.fi/~jpa/nanopb/
 To compile the library, you'll need these libraries:
 protobuf-compiler python-protobuf libprotobuf-dev
 
+The only runtime dependencies are memset() and memcpy().
+
 To run the tests, run make under the tests folder.
 If it completes without error, everything is fine.

docs/concepts.rst

@@ -50,6 +50,7 @@ There are a few generic rules for callback functions:
 #) Use state to store your own data, such as a file descriptor.
 #) *bytes_written* and *bytes_left* are updated by pb_write and pb_read.
 #) Your callback may be used with substreams. In this case *bytes_left*, *bytes_written* and *max_size* have smaller values than the original stream. Don't use these values to calculate pointers.
+#) Always read or write the full requested length of data. For example, POSIX *recv()* needs the *MSG_WAITALL* parameter to accomplish this.
 
 Output streams
 --------------
@@ -258,18 +259,14 @@ generates this field description array for the structure *Person_PhoneNumber*::
 Return values and error handling
 ================================
 
-Most functions in nanopb return bool: *true* means success, *false* means failure. If this is enough for you, skip this section.
+Most functions in nanopb return bool: *true* means success, *false* means failure. There is also some support for error messages for debugging purposes: the error messages go in *stream->errmsg*.
 
-For simplicity, nanopb doesn't define it's own error codes. This might be added if there is a compelling need for it. You can however deduce something about the error causes:
+The error messages help in guessing what is the underlying cause of the error. The most common error conditions are:
 
 1) Running out of memory. Because everything is allocated from the stack, nanopb can't detect this itself. Encoding or decoding the same type of a message always takes the same amount of stack space. Therefore, if it works once, it works always.
 2) Invalid field description. These are usually stored as constants, so if it works under the debugger, it always does.
-3) IO errors in your own stream callbacks. Because encoding/decoding stops at the first error, you can overwrite the *state* field in the struct and store your own error code there.
-4) Errors that happen in your callback functions. You can use the state field in the callback structure.
+3) IO errors in your own stream callbacks.
+4) Errors that happen in your callback functions.
 5) Exceeding the max_size or bytes_left of a stream.
 6) Exceeding the max_size of a string or array field
-7) Invalid protocol buffers binary message. It's not like you could recover from it anyway, so a simple failure should be enough.
-
-In my opinion, it is enough that 1. and 2. can be resolved using a debugger.
-
-However, you may be interested which of the remaining conditions caused the error. For 3. and 4., you can set and check the state. If you have to detect 5. and 6., you should convert the fields to callback type. Any remaining problem is of type 7.
+7) Invalid protocol buffers binary message.

docs/reference.rst

@@ -20,6 +20,8 @@ PB_FIELD_16BIT                 Add support for tag numbers > 255 and fields larg
                                Increases code size 3 bytes per each field. Compiler error will tell if you need this.
 PB_FIELD_32BIT                 Add support for tag numbers > 65535 and fields larger than 65535 bytes or 65535 array entries.
                                Increases code size 9 bytes per each field. Compiler error will tell if you need this.
+PB_NO_ERRMSG                   Disables the support for error messages; only error information is the true/false return value.
+                               Decreases the code size by a few hundred bytes.
 ============================  ================================================================================================
 
 The PB_MAX_REQUIRED_FIELDS, PB_FIELD_16BIT and PB_FIELD_32BIT settings allow raising some datatype limits to suit larger messages.
@@ -320,15 +322,15 @@ In addition to EOF, the pb_decode implementation supports terminating a message
 
 For optional fields, this function applies the default value and sets *has_<field>* to false if the field is not present.
 
-pb_decode_varint
+pb_decode_noinit
 ----------------
-Read and decode a varint_ encoded integer. ::
+Same as `pb_decode`_, except does not apply the default values to fields. ::
 
-    bool pb_decode_varint(pb_istream_t *stream, uint64_t *dest);
+    bool pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct);
 
-:stream:        Input stream to read from. 1-10 bytes will be read.
-:dest:          Storage for the decoded integer. Value is undefined on error.
-:returns:       True on success, false if value exceeds uint64_t range or an IO error happens.
+(parameters are the same as for `pb_decode`_.)
+
+The destination structure should be filled with zeros before calling this function. Doing a *memset* manually can be slightly faster than using `pb_decode`_ if you don't need any default values.
 
 pb_skip_varint
 --------------
@@ -373,48 +375,41 @@ Remove the data for a field from the stream, without actually decoding it::
 :wire_type:     Type of field to skip.
 :returns:       True on success, false on IO error.
 
-.. sidebar:: Field decoders
+.. sidebar:: Decoding fields manually
     
-    The functions with names beginning with *pb_dec_* are called field decoders. Each PB_LTYPE has an own field decoder, which handles translating from Protocol Buffers data to C data.
+    The functions with names beginning with *pb_decode_* are used when dealing with callback fields. The typical reason for using callbacks is to have an array of unlimited size. In that case, `pb_decode`_ will call your callback function repeatedly, which can then store the values into e.g. filesystem in the order received in.
 
-    Each field decoder reads and decodes a single value. For arrays, the decoder is called repeatedly.
+    For decoding numeric (including enumerated and boolean) values, use `pb_decode_varint`_, `pb_decode_svarint`_, `pb_decode_fixed32`_ and `pb_decode_fixed64`_. They take a pointer to a 32- or 64-bit C variable, which you may then cast to smaller datatype for storage.
 
-    You can use the decoders from your callbacks. Just be aware that the pb_field_t passed to the callback is not directly compatible 
-    with the *varint* field decoders. Instead, you must create a new pb_field_t structure and set the data_size according to the data type 
-    you pass to *dest*, e.g. *field.data_size = sizeof(int);*. Other fields in the *pb_field_t* don't matter.
+    For decoding strings and bytes fields, the length has already been decoded. You can therefore check the total length in *stream->state* and read the data using `pb_read`_.
 
-    The field decoder interface is a bit messy as a result of the interface required inside the nanopb library.
-    Eventually they may be replaced by separate wrapper functions with a more friendly interface.
+    Finally, for decoding submessages in a callback, simply use `pb_decode`_ and pass it the *SubMessage_fields* descriptor array.
 
-pb_dec_varint
--------------
-Field decoder for PB_LTYPE_VARINT. ::
+pb_decode_varint
+----------------
+Read and decode a varint_ encoded integer. ::
 
-    bool pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest)
+    bool pb_decode_varint(pb_istream_t *stream, uint64_t *dest);
 
 :stream:        Input stream to read from. 1-10 bytes will be read.
-:field:         Field description structure. Only *field->data_size* matters.
-:dest:          Pointer to destination integer. Must have size of *field->data_size* bytes.
-:returns:       True on success, false on IO errors or if `pb_decode_varint`_ fails.
+:dest:          Storage for the decoded integer. Value is undefined on error.
+:returns:       True on success, false if value exceeds uint64_t range or an IO error happens.
 
-This function first calls `pb_decode_varint`_. It then copies the first bytes of the 64-bit result value to *dest*, or on big endian architectures, the last bytes.
+pb_decode_svarint
+-----------------
+Similar to `pb_decode_varint`_, except that it performs zigzag-decoding on the value. This corresponds to the Protocol Buffers *sint32* and *sint64* datatypes. ::
 
-pb_dec_svarint
---------------
-Field decoder for PB_LTYPE_SVARINT. Similar to `pb_dec_varint`_, except that it performs zigzag-decoding on the value. ::
+    bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest);
 
-    bool pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
+(parameters are the same as `pb_decode_varint`_)
 
-(parameters are the same as `pb_dec_varint`_)
+pb_decode_fixed32
+-----------------
+Decode a *fixed32*, *sfixed32* or *float* value. ::
 
-pb_dec_fixed32
---------------
-Field decoder for PB_LTYPE_FIXED32. ::
-
-    bool pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
+    bool pb_decode_fixed32(pb_istream_t *stream, void *dest);
 
 :stream:        Input stream to read from. 4 bytes will be read.
-:field:         Not used.
 :dest:          Pointer to destination *int32_t*, *uint32_t* or *float*.
 :returns:       True on success, false on IO errors.
 
@@ -422,9 +417,9 @@ This function reads 4 bytes from the input stream.
 On big endian architectures, it then reverses the order of the bytes.
 Finally, it writes the bytes to *dest*.
 
-pb_dec_fixed64
---------------
-Field decoder for PB_LTYPE_FIXED64. ::
+pb_decode_fixed64
+-----------------
+Decode a *fixed64*, *sfixed64* or *double* value. ::
 
     bool pb_dec_fixed(pb_istream_t *stream, const pb_field_t *field, void *dest);
 
@@ -433,53 +428,28 @@ Field decoder for PB_LTYPE_FIXED64. ::
 :dest:          Pointer to destination *int64_t*, *uint64_t* or *double*.
 :returns:       True on success, false on IO errors.
 
-Same as `pb_dec_fixed32`_, except this reads 8 bytes.
+Same as `pb_decode_fixed32`_, except this reads 8 bytes.
 
-pb_dec_bytes
-------------
-Field decoder for PB_LTYPE_BYTES. Reads a length-prefixed block of bytes. ::
+pb_make_string_substream
+------------------------
+Decode the length for a field with wire type *PB_WT_STRING* and create a substream for reading the data. ::
 
-    bool pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
+    bool pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream);
 
-**Note:** This is an internal function that is not useful in decoder callbacks. To read bytes fields in callbacks, use 
-*stream->bytes_left* and `pb_read`_.
+:stream:        Original input stream to read the length and data from.
+:substream:     New substream that has limited length. Filled in by the function.
+:returns:       True on success, false if reading the length fails.
 
-:stream:        Input stream to read from.
-:field:         Field description structure. Only *field->data_size* matters.
-:dest:          Pointer to a structure similar to pb_bytes_array_t.
-:returns:       True on success, false on IO error or if length exceeds the array size.
+This function uses `pb_decode_varint`_ to read an integer from the stream. This is interpreted as a number of bytes, and the substream is set up so that its `bytes_left` is initially the same as the length, and its callback function and state the same as the parent stream.
 
-This function expects a pointer to a structure with a *size_t* field at start, and a variable sized byte array after it. It will deduce the maximum size of the array from *field->data_size*.
+pb_close_string_substream
+-------------------------
+Close the substream created with `pb_make_string_substream`_. ::
 
-pb_dec_string
--------------
-Field decoder for PB_LTYPE_STRING. Reads a length-prefixed string. ::
+    void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream);
 
-    bool pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
-
-**Note:** This is an internal function that is not useful in decoder callbacks. To read string fields in callbacks, use 
-*stream->bytes_left* and `pb_read`_.
-
-:stream:        Input stream to read from.
-:field:         Field description structure. Only *field->data_size* matters.
-:dest:          Pointer to a character array of size *field->data_size*.
-:returns:       True on success, false on IO error or if length exceeds the array size.
-
-This function null-terminates the string when successful. On error, the contents of the destination array is undefined.
-
-pb_dec_submessage
------------------
-Field decoder for PB_LTYPE_SUBMESSAGE. Calls `pb_decode`_ to perform the actual decoding. ::
-
-    bool pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest)
-
-**Note:** This is an internal function that is not useful in decoder callbacks. To read submessage fields in callbacks, use 
-`pb_decode`_ directly.
-
-:stream:        Input stream to read from.
-:field:         Field description structure. Only *field->ptr* matters.
-:dest:          Pointer to the destination structure.
-:returns:       True on success, false on IO error or if `pb_decode`_ fails.
-
-The *field->ptr* should be a pointer to *pb_field_t* array describing the submessage.
+:stream:        Original input stream to read the length and data from.
+:substream:     Substream to close
 
+This function copies back the state from the substream to the parent stream.
+It must be called after done with the substream.

example/client.c

@@ -72,7 +72,7 @@ bool listdir(int fd, char *path)
     
     if (!pb_decode(&input, ListFilesResponse_fields, &response))
     {
-        fprintf(stderr, "Decoding failed.\n");
+        fprintf(stderr, "Decode failed: %s\n", PB_GET_ERROR(&input));
         return false;
     }
     

example/server.c

@@ -55,7 +55,7 @@ void handle_connection(int connfd)
     
     if (!pb_decode(&input, ListFilesRequest_fields, &request))
     {
-        printf("Decoding failed.\n");
+        printf("Decode failed: %s\n", PB_GET_ERROR(&input));
         return;
     }
     

example_unions/decode.c

@@ -17,7 +17,7 @@
 const pb_field_t* decode_unionmessage_type(pb_istream_t *stream)
 {
     pb_wire_type_t wire_type;
-    int tag;
+    uint32_t tag;
     bool eof;
 
     while (pb_decode_tag(stream, &wire_type, &tag, &eof))
@@ -44,10 +44,14 @@ const pb_field_t* decode_unionmessage_type(pb_istream_t *stream)
 
 bool decode_unionmessage_contents(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
 {
-    pb_field_t field = {}; /* NB: Could get rid of this wrapper by fixing issue #2. */
-    field.ptr = fields;
+    pb_istream_t substream;
+    bool status;
+    if (!pb_make_string_substream(stream, &substream))
+        return false;
     
-    return pb_dec_submessage(stream, &field, dest_struct);
+    status = pb_decode(&substream, fields, dest_struct);
+    pb_close_string_substream(stream, &substream);
+    return status;
 }
 
 int main()
@@ -81,7 +85,7 @@ int main()
     
     if (!status)
     {
-        printf("Decoding failed.\n");
+        printf("Decode failed: %s\n", PB_GET_ERROR(&stream));
         return 1;
     }
     

pb.h

@@ -194,7 +194,25 @@ typedef enum {
 #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,(pb_type_t) 0,0,0}
+#define PB_LAST_FIELD {0,(pb_type_t) 0,0,0,0,0,0}
 
+/* 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.
+ * Some code space can be saved by disabling the error
+ * messages if not used.
+ */
+#ifdef PB_NO_ERRMSG
+#define PB_RETURN_ERROR(stream,msg) return false
+#define PB_GET_ERROR(stream) "(errmsg disabled)"
+#else
+#define PB_RETURN_ERROR(stream,msg) \
+    do {\
+        if ((stream)->errmsg == NULL) \
+            (stream)->errmsg = (msg); \
+        return false; \
+    } while(0)
+#define PB_GET_ERROR(stream) ((stream)->errmsg ? (stream)->errmsg : "(none)")
+#endif
 
 #endif

pb_decode.c

@@ -3,14 +3,15 @@
  * 2011 Petteri Aimonen <jpa@kapsi.fi>
  */
 
-
-#ifdef __GNUC__
-/* Verify that we remember to check all return values for proper error propagation */
-#define checkreturn __attribute__((warn_unused_result))
+/* The warn_unused_result attribute appeared first in gcc-3.4.0 */
+#if !defined(__GNUC__) || ( __GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
+    #define checkreturn
 #else
-#define checkreturn
+    /* Verify that we remember to check all return values for proper error propagation */
+    #define checkreturn __attribute__((warn_unused_result))
 #endif
 
+#define NANOPB_INTERNALS
 #include "pb.h"
 #include "pb_decode.h"
 #include <string.h>
@@ -38,10 +39,10 @@ static const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT] = {
 bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
 {
     if (stream->bytes_left < count)
-        return false;
+        PB_RETURN_ERROR(stream, "end-of-stream");
     
     if (!stream->callback(stream, buf, count))
-        return false;
+        PB_RETURN_ERROR(stream, "io error");
     
     stream->bytes_left -= count;
     return true;
@@ -94,7 +95,7 @@ bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
             return true;
     }
     
-    return false;
+    PB_RETURN_ERROR(stream, "varint overflow");
 }
 
 bool checkreturn pb_skip_varint(pb_istream_t *stream)
@@ -117,11 +118,11 @@ bool checkreturn pb_skip_string(pb_istream_t *stream)
     return pb_read(stream, NULL, length);
 }
 
-bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, int *tag, bool *eof)
+bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof)
 {
     uint32_t temp;
     *eof = false;
-    *wire_type = 0;
+    *wire_type = (pb_wire_type_t) 0;
     *tag = 0;
     
     if (!pb_decode_varint32(stream, &temp))
@@ -151,7 +152,7 @@ bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
         case PB_WT_64BIT: return pb_read(stream, NULL, 8);
         case PB_WT_STRING: return pb_skip_string(stream);
         case PB_WT_32BIT: return pb_read(stream, NULL, 4);
-        default: return false;
+        default: PB_RETURN_ERROR(stream, "invalid wire_type");
     }
 }
 
@@ -181,15 +182,14 @@ static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire
             *size = 4;
             return pb_read(stream, buf, 4);
         
-        default: return false;
+        default: PB_RETURN_ERROR(stream, "invalid wire_type");
     }
 }
 
 /* Decode string length from stream and return a substream with limited length.
- * Before disposing the substream, remember to copy the substream->state back
- * to stream->state.
+ * Remember to close the substream using pb_close_string_substream().
  */
-static bool checkreturn make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
+bool checkreturn pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
 {
     uint32_t size;
     if (!pb_decode_varint32(stream, &size))
@@ -197,13 +197,18 @@ static bool checkreturn make_string_substream(pb_istream_t *stream, pb_istream_t
     
     *substream = *stream;
     if (substream->bytes_left < size)
-        return false;
+        PB_RETURN_ERROR(stream, "parent stream too short");
     
     substream->bytes_left = size;
     stream->bytes_left -= size;
     return true;
 }
 
+void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream)
+{
+    stream->state = substream->state;
+}
+
 /* Iterator for pb_field_t list */
 typedef struct {
     const pb_field_t *start; /* Start of the pb_field_t array */
@@ -253,7 +258,7 @@ static bool pb_field_next(pb_field_iterator_t *iter)
     return notwrapped;
 }
 
-static bool checkreturn pb_field_find(pb_field_iterator_t *iter, int tag)
+static bool checkreturn pb_field_find(pb_field_iterator_t *iter, uint32_t tag)
 {
     int start = iter->field_index;
     
@@ -288,9 +293,10 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t
                 && PB_LTYPE(iter->current->type) <= PB_LTYPE_LAST_PACKABLE)
             {
                 /* Packed array */
+                bool status;
                 size_t *size = (size_t*)iter->pSize;
                 pb_istream_t substream;
-                if (!make_string_substream(stream, &substream))
+                if (!pb_make_string_substream(stream, &substream))
                     return false;
                 
                 while (substream.bytes_left && *size < iter->current->array_size)
@@ -300,7 +306,9 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t
                         return false;
                     (*size)++;
                 }
-                return (substream.bytes_left == 0);
+                status = (substream.bytes_left == 0);
+                pb_close_string_substream(stream, &substream);
+                return status;
             }
             else
             {
@@ -308,7 +316,7 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t
                 size_t *size = (size_t*)iter->pSize;
                 void *pItem = (uint8_t*)iter->pData + iter->current->data_size * (*size);
                 if (*size >= iter->current->array_size)
-                    return false;
+                    PB_RETURN_ERROR(stream, "array overflow");
                 
                 (*size)++;
                 return func(stream, iter->current, pItem);
@@ -325,16 +333,16 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t
             {
                 pb_istream_t substream;
                 
-                if (!make_string_substream(stream, &substream))
+                if (!pb_make_string_substream(stream, &substream))
                     return false;
                 
                 while (substream.bytes_left)
                 {
                     if (!pCallback->funcs.decode(&substream, iter->current, pCallback->arg))
-                        return false;
+                        PB_RETURN_ERROR(stream, "callback failed");
                 }
                 
-                stream->state = substream.state;
+                pb_close_string_substream(stream, &substream);
                 return true;
             }
             else
@@ -356,7 +364,7 @@ static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_t
         }
         
         default:
-            return false;
+            PB_RETURN_ERROR(stream, "invalid field type");
     }
 }
 
@@ -390,7 +398,7 @@ static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_str
         }
         else if (PB_LTYPE(iter.current->type) == PB_LTYPE_SUBMESSAGE)
         {
-            pb_message_set_to_defaults(iter.current->ptr, iter.pData);
+            pb_message_set_to_defaults((const pb_field_t *) iter.current->ptr, iter.pData);
         }
         else if (iter.current->ptr != NULL)
         {
@@ -407,18 +415,16 @@ static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_str
  * Decode all fields *
  *********************/
 
-bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
+bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
 {
-    uint8_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 7) / 8] = {}; /* Used to check for required fields */
+    uint8_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 7) / 8] = {0}; /* Used to check for required fields */
     pb_field_iterator_t iter;
     
-    pb_message_set_to_defaults(fields, dest_struct);
-    
     pb_field_init(&iter, fields, dest_struct);
     
     while (stream->bytes_left)
     {
-        int tag;
+        uint32_t tag;
         pb_wire_type_t wire_type;
         bool eof;
         
@@ -455,87 +461,119 @@ bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void
             iter.required_field_index < PB_MAX_REQUIRED_FIELDS &&
             !(fields_seen[iter.required_field_index >> 3] & (1 << (iter.required_field_index & 7))))
         {
-            return false;
+            PB_RETURN_ERROR(stream, "missing required field");
         }
     } while (pb_field_next(&iter));
     
     return true;
 }
 
+bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
+{
+    pb_message_set_to_defaults(fields, dest_struct);
+    return pb_decode_noinit(stream, fields, dest_struct);
+}
+
 /* Field decoders */
 
-/* Copy destsize bytes from src so that values are casted properly.
- * On little endian machine, copy first n bytes of src
- * On big endian machine, copy last n bytes of src
- * srcsize must always be larger than destsize
- */
-static void endian_copy(void *dest, void *src, size_t destsize, size_t srcsize)
+bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
 {
-#ifdef __BIG_ENDIAN__
-    memcpy(dest, (char*)src + (srcsize - destsize), destsize);
-#else
-    UNUSED(srcsize);
-    memcpy(dest, src, destsize);
-#endif
+    uint64_t value;
+    if (!pb_decode_varint(stream, &value))
+        return false;
+    
+    if (value & 1)
+        *dest = ~(value >> 1);
+    else
+        *dest = value >> 1;
+    
+    return true;
+}
+
+bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
+{
+    #ifdef __BIG_ENDIAN__
+    uint8_t *bytes = (uint8_t*)dest;
+    uint8_t lebytes[4];
+    
+    if (!pb_read(stream, lebytes, 4))
+        return false;
+    
+    bytes[0] = lebytes[3];
+    bytes[1] = lebytes[2];
+    bytes[2] = lebytes[1];
+    bytes[3] = lebytes[0];
+    return true;
+    #else
+    return pb_read(stream, (uint8_t*)dest, 4);
+    #endif   
+}
+
+bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
+{
+    #ifdef __BIG_ENDIAN__
+    uint8_t *bytes = (uint8_t*)dest;
+    uint8_t lebytes[8];
+    
+    if (!pb_read(stream, lebytes, 8))
+        return false;
+    
+    bytes[0] = lebytes[7];
+    bytes[1] = lebytes[6];
+    bytes[2] = lebytes[5];
+    bytes[3] = lebytes[4];
+    bytes[4] = lebytes[3];
+    bytes[5] = lebytes[2];
+    bytes[6] = lebytes[1];
+    bytes[7] = lebytes[0];
+    return true;
+    #else
+    return pb_read(stream, (uint8_t*)dest, 8);
+    #endif   
 }
 
 bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest)
 {
-    uint64_t temp;
-    bool status = pb_decode_varint(stream, &temp);
-    endian_copy(dest, &temp, field->data_size, sizeof(temp));
+    uint64_t value;
+    bool status = pb_decode_varint(stream, &value);
+    
+    switch (field->data_size)
+    {
+        case 1: *(uint8_t*)dest = value; break;
+        case 2: *(uint16_t*)dest = value; break;
+        case 4: *(uint32_t*)dest = value; break;
+        case 8: *(uint64_t*)dest = value; break;
+        default: PB_RETURN_ERROR(stream, "invalid data_size");
+    }
+    
     return status;
 }
 
 bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
 {
-    uint64_t temp;
-    bool status = pb_decode_varint(stream, &temp);
-    temp = (temp >> 1) ^ -(int64_t)(temp & 1);
-    endian_copy(dest, &temp, field->data_size, sizeof(temp));
+    int64_t value;
+    bool status = pb_decode_svarint(stream, &value);
+    
+    switch (field->data_size)
+    {
+        case 4: *(int32_t*)dest = value; break;
+        case 8: *(int64_t*)dest = value; break;
+        default: PB_RETURN_ERROR(stream, "invalid data_size");
+    }
+    
     return status;
 }
 
 bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest)
 {
-#ifdef __BIG_ENDIAN__
-    uint8_t bytes[4] = {0};
-    bool status = pb_read(stream, bytes, 4);
-    if (status) {
-        uint8_t *d = (uint8_t*)dest;
-        d[0] = bytes[3];
-        d[1] = bytes[2];
-        d[2] = bytes[1];
-        d[3] = bytes[0];
-    }
-    return status;
-#else
     UNUSED(field);
-    return pb_read(stream, (uint8_t*)dest, 4);
-#endif
+    return pb_decode_fixed32(stream, dest);
 }
 
 bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest)
 {
-#ifdef __BIG_ENDIAN__
-    uint8_t bytes[8] = {0};
-    bool status = pb_read(stream, bytes, 8);
-    if (status) {
-        uint8_t *d = (uint8_t*)dest;
-        d[0] = bytes[7];
-        d[1] = bytes[6];
-        d[2] = bytes[5]; 
-        d[3] = bytes[4];
-        d[4] = bytes[3];
-        d[5] = bytes[2];
-        d[6] = bytes[1];
-        d[7] = bytes[0];
-    }
-    return status;
-#else
     UNUSED(field);
-    return pb_read(stream, (uint8_t*)dest, 8);
-#endif
+    return pb_decode_fixed64(stream, dest);
 }
 
 bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest)
@@ -549,7 +587,7 @@ bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, voi
     
     /* Check length, noting the space taken by the size_t header. */
     if (x->size > field->data_size - offsetof(pb_bytes_array_t, bytes))
-        return false;
+        PB_RETURN_ERROR(stream, "bytes overflow");
     
     return pb_read(stream, x->bytes, x->size);
 }
@@ -563,7 +601,7 @@ bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, vo
     
     /* Check length, noting the null terminator */
     if (size + 1 > field->data_size)
-        return false;
+        PB_RETURN_ERROR(stream, "string overflow");
     
     status = pb_read(stream, (uint8_t*)dest, size);
     *((uint8_t*)dest + size) = 0;
@@ -574,14 +612,21 @@ bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field
 {
     bool status;
     pb_istream_t substream;
+    const pb_field_t* submsg_fields = (const pb_field_t*)field->ptr;
     
-    if (!make_string_substream(stream, &substream))
+    if (!pb_make_string_substream(stream, &substream))
         return false;
     
     if (field->ptr == NULL)
-        return false;
+        PB_RETURN_ERROR(stream, "invalid field descriptor");
     
-    status = pb_decode(&substream, (pb_field_t*)field->ptr, dest);
-    stream->state = substream.state;
+    /* New array entries need to be initialized, while required and optional
+     * submessages have already been initialized in the top-level pb_decode. */
+    if (PB_HTYPE(field->type) == PB_HTYPE_ARRAY)
+        status = pb_decode(&substream, submsg_fields, dest);
+    else
+        status = pb_decode_noinit(&substream, submsg_fields, dest);
+    
+    pb_close_string_substream(stream, &substream);
     return status;
 }

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.
@@ -33,6 +33,10 @@ 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;
+    
+#ifndef PB_NO_ERRMSG
+    const char *errmsg;
+#endif
 };
 
 pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize);
@@ -44,24 +48,49 @@ 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.
  */
 
-bool pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, int *tag, bool *eof);
+/* 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);
 
-/* --- 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.
+/* 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);
+
+/* 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 +100,8 @@ 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
+
 #endif

pb_encode.c

@@ -8,14 +8,14 @@
 #include "pb_encode.h"
 #include <string.h>
 
-#ifdef __GNUC__
-/* Verify that we remember to check all return values for proper error propagation */
-#define checkreturn __attribute__((warn_unused_result))
+/* The warn_unused_result attribute appeared first in gcc-3.4.0 */
+#if !defined(__GNUC__) || ( __GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
+    #define checkreturn
 #else
-#define checkreturn
+    /* Verify that we remember to check all return values for proper error propagation */
+    #define checkreturn __attribute__((warn_unused_result))
 #endif
 
-
 typedef bool (*pb_encoder_t)(pb_ostream_t *stream, const pb_field_t *field, const void *src) checkreturn;
 
 /* --- Function pointers to field encoders ---
@@ -99,7 +99,7 @@ static bool checkreturn encode_array(pb_ostream_t *stream, const pb_field_t *fie
         }
         else
         {
-            pb_ostream_t sizestream = {0};
+            pb_ostream_t sizestream = {0,0,0,0};
             p = pData;
             for (i = 0; i < count; i++)
             {
@@ -168,7 +168,7 @@ bool checkreturn pb_encode(pb_ostream_t *stream, const pb_field_t fields[], cons
                 break;
             
             case PB_HTYPE_OPTIONAL:
-                if (*(bool*)pSize)
+                if (*(const bool*)pSize)
                 {
                     if (!pb_encode_tag_for_field(stream, field))
                         return false;
@@ -179,13 +179,13 @@ bool checkreturn pb_encode(pb_ostream_t *stream, const pb_field_t fields[], cons
                 break;
             
             case PB_HTYPE_ARRAY:
-                if (!encode_array(stream, field, pData, *(size_t*)pSize, func))
+                if (!encode_array(stream, field, pData, *(const size_t*)pSize, func))
                     return false;
                 break;
             
             case PB_HTYPE_CALLBACK:
             {
-                pb_callback_t *callback = (pb_callback_t*)pData;
+                const pb_callback_t *callback = (const pb_callback_t*)pData;
                 if (callback->funcs.encode != NULL)
                 {
                     if (!callback->funcs.encode(stream, field, callback->arg))
@@ -243,7 +243,7 @@ bool checkreturn pb_encode_fixed32(pb_ostream_t *stream, const void *value)
     lebytes[3] = bytes[0];
     return pb_write(stream, lebytes, 4);
     #else
-    return pb_write(stream, (uint8_t*)value, 4);
+    return pb_write(stream, (const uint8_t*)value, 4);
     #endif
 }
 
@@ -262,14 +262,14 @@ bool checkreturn pb_encode_fixed64(pb_ostream_t *stream, const void *value)
     lebytes[7] = bytes[0];
     return pb_write(stream, lebytes, 8);
     #else
-    return pb_write(stream, (uint8_t*)value, 8);
+    return pb_write(stream, (const uint8_t*)value, 8);
     #endif
 }
 
 bool checkreturn pb_encode_tag(pb_ostream_t *stream, pb_wire_type_t wiretype, int field_number)
 {
-    int tag = wiretype | (field_number << 3);
-    return pb_encode_varint(stream, (uint64_t)tag);
+    uint64_t tag = wiretype | (field_number << 3);
+    return pb_encode_varint(stream, tag);
 }
 
 bool checkreturn pb_encode_tag_for_field(pb_ostream_t *stream, const pb_field_t *field)
@@ -314,7 +314,7 @@ bool checkreturn pb_encode_string(pb_ostream_t *stream, const uint8_t *buffer, s
 bool checkreturn pb_encode_submessage(pb_ostream_t *stream, const pb_field_t fields[], const void *src_struct)
 {
     /* First calculate the message size using a non-writing substream. */
-    pb_ostream_t substream = {0};
+    pb_ostream_t substream = {0,0,0,0};
     size_t size;
     bool status;
     
@@ -358,10 +358,10 @@ bool checkreturn pb_enc_varint(pb_ostream_t *stream, const pb_field_t *field, co
     
     switch (field->data_size)
     {
-        case 1: value = *(uint8_t*)src; break;
-        case 2: value = *(uint16_t*)src; break;
-        case 4: value = *(uint32_t*)src; break;
-        case 8: value = *(uint64_t*)src; break;
+        case 1: value = *(const uint8_t*)src; break;
+        case 2: value = *(const uint16_t*)src; break;
+        case 4: value = *(const uint32_t*)src; break;
+        case 8: value = *(const uint64_t*)src; break;
         default: return false;
     }
     
@@ -374,8 +374,8 @@ bool checkreturn pb_enc_svarint(pb_ostream_t *stream, const pb_field_t *field, c
     
     switch (field->data_size)
     {
-        case 4: value = *(int32_t*)src; break;
-        case 8: value = *(int64_t*)src; break;
+        case 4: value = *(const int32_t*)src; break;
+        case 8: value = *(const int64_t*)src; break;
         default: return false;
     }
     
@@ -396,7 +396,7 @@ bool checkreturn pb_enc_fixed32(pb_ostream_t *stream, const pb_field_t *field, c
 
 bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src)
 {
-    pb_bytes_array_t *bytes = (pb_bytes_array_t*)src;
+    const pb_bytes_array_t *bytes = (const pb_bytes_array_t*)src;
     UNUSED(field);
     return pb_encode_string(stream, bytes->bytes, bytes->size);
 }
@@ -404,7 +404,7 @@ bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, con
 bool checkreturn pb_enc_string(pb_ostream_t *stream, const pb_field_t *field, const void *src)
 {
     UNUSED(field);
-    return pb_encode_string(stream, (uint8_t*)src, strlen((char*)src));
+    return pb_encode_string(stream, (const uint8_t*)src, strlen((const char*)src));
 }
 
 bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field, const void *src)
@@ -412,6 +412,6 @@ bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field
     if (field->ptr == NULL)
         return false;
     
-    return pb_encode_submessage(stream, (pb_field_t*)field->ptr, src);
+    return pb_encode_submessage(stream, (const pb_field_t*)field->ptr, src);
 }
 

tests/Makefile

@@ -3,20 +3,32 @@ LDFLAGS=--coverage
 DEPS=../pb_decode.h ../pb_encode.h ../pb.h person.pb.h callbacks.pb.h unittests.h unittestproto.pb.h alltypes.pb.h missing_fields.pb.h
 TESTS=test_decode1 test_encode1 decode_unittests encode_unittests test_no_messages
 
+# More strict checks for the core part of nanopb
+CFLAGS_CORE=-pedantic -Wextra -Wcast-qual -Wlogical-op
+
 all: breakpoints $(TESTS) run_unittests
 
 clean:
 	rm -f $(TESTS) person.pb* alltypes.pb* *.o *.gcda *.gcno
 
+%.pb.o: %.pb.c %.pb.h
+	$(CC) $(CFLAGS) $(CFLAGS_CORE) -c -o $@ $<
+
 %.o: %.c
 %.o: %.c $(DEPS)
 	$(CC) $(CFLAGS) -c -o $@ $<
 
 pb_encode.o: ../pb_encode.c $(DEPS)
-	$(CC) $(CFLAGS) -c -o $@ $<
+	$(CC) $(CFLAGS) $(CFLAGS_CORE) -c -o $@ $<
 pb_decode.o: ../pb_decode.c $(DEPS)
-	$(CC) $(CFLAGS) -c -o $@ $<
+	$(CC) $(CFLAGS) $(CFLAGS_CORE) -c -o $@ $<
 
+pb_encode.cxx.o: ../pb_encode.c $(DEPS)
+	$(CXX) $(CFLAGS) $(CFLAGS_CORE) -c -o $@ $<
+pb_decode.cxx.o: ../pb_decode.c $(DEPS)
+	$(CXX) $(CFLAGS) $(CFLAGS_CORE) -c -o $@ $<
+
+test_cxxcompile: pb_encode.cxx.o pb_decode.cxx.o
 test_decode1: test_decode1.o pb_decode.o person.pb.o
 test_decode2: test_decode2.o pb_decode.o person.pb.o
 test_decode3: test_decode3.o pb_decode.o alltypes.pb.o
@@ -43,7 +55,7 @@ coverage: run_unittests
 	gcov pb_encode.gcda
 	gcov pb_decode.gcda
 
-run_unittests: decode_unittests encode_unittests test_encode1 test_encode2 test_encode3 test_decode1 test_decode2 test_decode3 test_encode_callbacks test_decode_callbacks test_missing_fields
+run_unittests: decode_unittests encode_unittests test_cxxcompile test_encode1 test_encode2 test_encode3 test_decode1 test_decode2 test_decode3 test_encode_callbacks test_decode_callbacks test_missing_fields
 	rm -f *.gcda
 	
 	./decode_unittests > /dev/null
@@ -62,7 +74,8 @@ run_unittests: decode_unittests encode_unittests test_encode1 test_encode2 test_
 	"`./test_encode_callbacks | protoc --decode=TestMessage callbacks.proto`" ]
 
 	./test_encode3 | ./test_decode3
-	./test_encode3 | protoc --decode=AllTypes -I. -I../generator -I/usr/include alltypes.proto >/dev/null
+	./test_encode3 1 | ./test_decode3 1
+	./test_encode3 1 | protoc --decode=AllTypes -I. -I../generator -I/usr/include alltypes.proto >/dev/null
 	
 	./test_missing_fields
 

tests/alltypes.proto

@@ -1,11 +1,13 @@
 import "nanopb.proto";
 
 message SubMessage {
-    required string substuff1 = 1 [(nanopb).max_size = 16];
-    required int32 substuff2 = 2;
+    required string substuff1 = 1 [(nanopb).max_size = 16, default = "1"];
+    required int32 substuff2 = 2 [default = 2];
+    optional fixed32 substuff3 = 3 [default = 3];
 }
 
 enum MyEnum {
+    Zero = 0;
     First = 1;
     Second = 2;
     Truth = 42;
@@ -33,6 +35,49 @@ message AllTypes {
     required SubMessage req_submsg  = 16;
     required MyEnum     req_enum    = 17;
     
+    
+    repeated int32      rep_int32   = 21 [(nanopb).max_count = 5];
+    repeated int64      rep_int64   = 22 [(nanopb).max_count = 5];
+    repeated uint32     rep_uint32  = 23 [(nanopb).max_count = 5];
+    repeated uint64     rep_uint64  = 24 [(nanopb).max_count = 5];
+    repeated sint32     rep_sint32  = 25 [(nanopb).max_count = 5];
+    repeated sint64     rep_sint64  = 26 [(nanopb).max_count = 5];
+    repeated bool       rep_bool    = 27 [(nanopb).max_count = 5];
+    
+    repeated fixed32    rep_fixed32 = 28 [(nanopb).max_count = 5];
+    repeated sfixed32   rep_sfixed32= 29 [(nanopb).max_count = 5];
+    repeated float      rep_float   = 30 [(nanopb).max_count = 5];
+    
+    repeated fixed64    rep_fixed64 = 31 [(nanopb).max_count = 5];
+    repeated sfixed64   rep_sfixed64= 32 [(nanopb).max_count = 5];
+    repeated double     rep_double  = 33 [(nanopb).max_count = 5];
+    
+    repeated string     rep_string  = 34 [(nanopb).max_size = 16, (nanopb).max_count = 5];
+    repeated bytes      rep_bytes   = 35 [(nanopb).max_size = 16, (nanopb).max_count = 5];
+    repeated SubMessage rep_submsg  = 36 [(nanopb).max_count = 5];
+    repeated MyEnum     rep_enum    = 37 [(nanopb).max_count = 5];
+    
+    optional int32      opt_int32   = 41 [default = 4041];
+    optional int64      opt_int64   = 42 [default = 4042];
+    optional uint32     opt_uint32  = 43 [default = 4043];
+    optional uint64     opt_uint64  = 44 [default = 4044];
+    optional sint32     opt_sint32  = 45 [default = 4045];
+    optional sint64     opt_sint64  = 46 [default = 4046];
+    optional bool       opt_bool    = 47 [default = false];
+    
+    optional fixed32    opt_fixed32 = 48 [default = 4048];
+    optional sfixed32   opt_sfixed32= 49 [default = 4049];
+    optional float      opt_float   = 50 [default = 4050];
+    
+    optional fixed64    opt_fixed64 = 51 [default = 4051];
+    optional sfixed64   opt_sfixed64= 52 [default = 4052];
+    optional double     opt_double  = 53 [default = 4053];
+    
+    optional string     opt_string  = 54 [(nanopb).max_size = 16, default = "4054"];
+    optional bytes      opt_bytes   = 55 [(nanopb).max_size = 16, default = "4055"];
+    optional SubMessage opt_submsg  = 56;
+    optional MyEnum     opt_enum    = 57 [default = Second];
+
     // Just to make sure that the size of the fields has been calculated
     // properly, i.e. otherwise a bug in last field might not be detected.
     required int32      end = 99;

tests/decode_unittests.c

@@ -1,3 +1,5 @@
+#define NANOPB_INTERNALS
+
 #include <stdio.h>
 #include <string.h>
 #include "pb_decode.h"

tests/test_decode1.c

@@ -69,7 +69,7 @@ int main()
     /* Decode and print out the stuff */
     if (!print_person(&stream))
     {
-        printf("Parsing failed.\n");
+        printf("Parsing failed: %s\n", PB_GET_ERROR(&stream));
         return 1;
     } else {
         return 0;

tests/test_decode2.c

@@ -82,7 +82,7 @@ int main()
     pb_istream_t stream = {&callback, stdin, 10000};
     if (!print_person(&stream))
     {
-        printf("Parsing failed.\n");
+        printf("Parsing failed: %s\n", PB_GET_ERROR(&stream));
         return 1;
     } else {
         return 0;

tests/test_decode3.c

@@ -1,10 +1,11 @@
-/* Tests the decoding of all types. Currently only in the 'required' variety.
+/* Tests the decoding of all types.
  * This is the counterpart of test_encode3.
  * Run e.g. ./test_encode3 | ./test_decode3
  */
 
 #include <stdio.h>
 #include <string.h>
+#include <stdlib.h>
 #include <pb_decode.h>
 #include "alltypes.pb.h"
 
@@ -15,9 +16,12 @@
 
 /* This function is called once from main(), it handles
    the decoding and checks the fields. */
-bool check_alltypes(pb_istream_t *stream)
+bool check_alltypes(pb_istream_t *stream, int mode)
 {
-    AllTypes alltypes = {};
+    AllTypes alltypes;
+    
+    /* Fill with garbage to better detect initialization errors */
+    memset(&alltypes, 0xAA, sizeof(alltypes));
     
     if (!pb_decode(stream, AllTypes_fields, &alltypes))
         return false;
@@ -43,26 +47,146 @@ bool check_alltypes(pb_istream_t *stream)
     TEST(memcmp(alltypes.req_bytes.bytes, "1015", 4) == 0);
     TEST(strcmp(alltypes.req_submsg.substuff1, "1016") == 0);
     TEST(alltypes.req_submsg.substuff2 == 1016);
+    TEST(alltypes.req_submsg.substuff3 == 3);
     TEST(alltypes.req_enum == MyEnum_Truth);
     
+    TEST(alltypes.rep_int32_count == 5 && alltypes.rep_int32[4] == 2001 && alltypes.rep_int32[0] == 0);
+    TEST(alltypes.rep_int64_count == 5 && alltypes.rep_int64[4] == 2002 && alltypes.rep_int64[0] == 0);
+    TEST(alltypes.rep_uint32_count == 5 && alltypes.rep_uint32[4] == 2003 && alltypes.rep_uint32[0] == 0);
+    TEST(alltypes.rep_uint64_count == 5 && alltypes.rep_uint64[4] == 2004 && alltypes.rep_uint64[0] == 0);
+    TEST(alltypes.rep_sint32_count == 5 && alltypes.rep_sint32[4] == 2005 && alltypes.rep_sint32[0] == 0);
+    TEST(alltypes.rep_sint64_count == 5 && alltypes.rep_sint64[4] == 2006 && alltypes.rep_sint64[0] == 0);
+    TEST(alltypes.rep_bool_count == 5 && alltypes.rep_bool[4] == true && alltypes.rep_bool[0] == false);
+    
+    TEST(alltypes.rep_fixed32_count == 5 && alltypes.rep_fixed32[4] == 2008 && alltypes.rep_fixed32[0] == 0);
+    TEST(alltypes.rep_sfixed32_count == 5 && alltypes.rep_sfixed32[4] == 2009 && alltypes.rep_sfixed32[0] == 0);
+    TEST(alltypes.rep_float_count == 5 && alltypes.rep_float[4] == 2010.0f && alltypes.rep_float[0] == 0.0f);
+    
+    TEST(alltypes.rep_fixed64_count == 5 && alltypes.rep_fixed64[4] == 2011 && alltypes.rep_fixed64[0] == 0);
+    TEST(alltypes.rep_sfixed64_count == 5 && alltypes.rep_sfixed64[4] == 2012 && alltypes.rep_sfixed64[0] == 0);
+    TEST(alltypes.rep_double_count == 5 && alltypes.rep_double[4] == 2013.0 && alltypes.rep_double[0] == 0.0);
+    
+    TEST(alltypes.rep_string_count == 5 && strcmp(alltypes.rep_string[4], "2014") == 0 && alltypes.rep_string[0][0] == '\0');
+    TEST(alltypes.rep_bytes_count == 5 && alltypes.rep_bytes[4].size == 4 && alltypes.rep_bytes[0].size == 0);
+    TEST(memcmp(alltypes.rep_bytes[4].bytes, "2015", 4) == 0);
+
+    TEST(alltypes.rep_submsg_count == 5);
+    TEST(strcmp(alltypes.rep_submsg[4].substuff1, "2016") == 0 && alltypes.rep_submsg[0].substuff1[0] == '\0');
+    TEST(alltypes.rep_submsg[4].substuff2 == 2016 && alltypes.rep_submsg[0].substuff2 == 0);
+    TEST(alltypes.rep_submsg[4].substuff3 == 2016 && alltypes.rep_submsg[0].substuff3 == 3);
+    
+    TEST(alltypes.rep_enum_count == 5 && alltypes.rep_enum[4] == MyEnum_Truth && alltypes.rep_enum[0] == MyEnum_Zero);
+    
+    if (mode == 0)
+    {
+        /* Expect default values */
+        TEST(alltypes.has_opt_int32     == false);
+        TEST(alltypes.opt_int32         == 4041);
+        TEST(alltypes.has_opt_int64     == false);
+        TEST(alltypes.opt_int64         == 4042);
+        TEST(alltypes.has_opt_uint32    == false);
+        TEST(alltypes.opt_uint32        == 4043);
+        TEST(alltypes.has_opt_uint64    == false);
+        TEST(alltypes.opt_uint64        == 4044);
+        TEST(alltypes.has_opt_sint32    == false);
+        TEST(alltypes.opt_sint32        == 4045);
+        TEST(alltypes.has_opt_sint64    == false);
+        TEST(alltypes.opt_sint64        == 4046);
+        TEST(alltypes.has_opt_bool      == false);
+        TEST(alltypes.opt_bool          == false);
+        
+        TEST(alltypes.has_opt_fixed32   == false);
+        TEST(alltypes.opt_fixed32       == 4048);
+        TEST(alltypes.has_opt_sfixed32  == false);
+        TEST(alltypes.opt_sfixed32      == 4049);
+        TEST(alltypes.has_opt_float     == false);
+        TEST(alltypes.opt_float         == 4050.0f);
+        
+        TEST(alltypes.has_opt_fixed64   == false);
+        TEST(alltypes.opt_fixed64       == 4051);
+        TEST(alltypes.has_opt_sfixed64  == false);
+        TEST(alltypes.opt_sfixed64      == 4052);
+        TEST(alltypes.has_opt_double    == false);
+        TEST(alltypes.opt_double        == 4053.0);
+        
+        TEST(alltypes.has_opt_string    == false);
+        TEST(strcmp(alltypes.opt_string, "4054") == 0);
+        TEST(alltypes.has_opt_bytes     == false);
+        TEST(alltypes.opt_bytes.size == 4);
+        TEST(memcmp(alltypes.opt_bytes.bytes, "4055", 4) == 0);
+        TEST(alltypes.has_opt_submsg    == false);
+        TEST(strcmp(alltypes.opt_submsg.substuff1, "1") == 0);
+        TEST(alltypes.opt_submsg.substuff2 == 2);
+        TEST(alltypes.opt_submsg.substuff3 == 3);
+        TEST(alltypes.has_opt_enum     == false);
+        TEST(alltypes.opt_enum == MyEnum_Second);
+    }
+    else
+    {
+        /* Expect filled-in values */
+        TEST(alltypes.has_opt_int32     == true);
+        TEST(alltypes.opt_int32         == 3041);
+        TEST(alltypes.has_opt_int64     == true);
+        TEST(alltypes.opt_int64         == 3042);
+        TEST(alltypes.has_opt_uint32    == true);
+        TEST(alltypes.opt_uint32        == 3043);
+        TEST(alltypes.has_opt_uint64    == true);
+        TEST(alltypes.opt_uint64        == 3044);
+        TEST(alltypes.has_opt_sint32    == true);
+        TEST(alltypes.opt_sint32        == 3045);
+        TEST(alltypes.has_opt_sint64    == true);
+        TEST(alltypes.opt_sint64        == 3046);
+        TEST(alltypes.has_opt_bool      == true);
+        TEST(alltypes.opt_bool          == true);
+        
+        TEST(alltypes.has_opt_fixed32   == true);
+        TEST(alltypes.opt_fixed32       == 3048);
+        TEST(alltypes.has_opt_sfixed32  == true);
+        TEST(alltypes.opt_sfixed32      == 3049);
+        TEST(alltypes.has_opt_float     == true);
+        TEST(alltypes.opt_float         == 3050.0f);
+        
+        TEST(alltypes.has_opt_fixed64   == true);
+        TEST(alltypes.opt_fixed64       == 3051);
+        TEST(alltypes.has_opt_sfixed64  == true);
+        TEST(alltypes.opt_sfixed64      == 3052);
+        TEST(alltypes.has_opt_double    == true);
+        TEST(alltypes.opt_double        == 3053.0);
+        
+        TEST(alltypes.has_opt_string    == true);
+        TEST(strcmp(alltypes.opt_string, "3054") == 0);
+        TEST(alltypes.has_opt_bytes     == true);
+        TEST(alltypes.opt_bytes.size == 4);
+        TEST(memcmp(alltypes.opt_bytes.bytes, "3055", 4) == 0);
+        TEST(alltypes.has_opt_submsg    == true);
+        TEST(strcmp(alltypes.opt_submsg.substuff1, "3056") == 0);
+        TEST(alltypes.opt_submsg.substuff2 == 3056);
+        TEST(alltypes.opt_submsg.substuff3 == 3);
+        TEST(alltypes.has_opt_enum      == true);
+        TEST(alltypes.opt_enum == MyEnum_Truth);
+    }
+    
     TEST(alltypes.end == 1099);
     
     return true;
 }
 
-int main()
+int main(int argc, char **argv)
 {
+    /* Whether to expect the optional values or the default values. */
+    int mode = (argc > 1) ? atoi(argv[1]) : 0;
+    
     /* Read the data into buffer */
-    uint8_t buffer[512];
+    uint8_t buffer[1024];
     size_t count = fread(buffer, 1, sizeof(buffer), stdin);
     
     /* Construct a pb_istream_t for reading from the buffer */
     pb_istream_t stream = pb_istream_from_buffer(buffer, count);
     
     /* Decode and print out the stuff */
-    if (!check_alltypes(&stream))
+    if (!check_alltypes(&stream, mode))
     {
-        printf("Parsing failed.\n");
+        printf("Parsing failed: %s\n", PB_GET_ERROR(&stream));
         return 1;
     } else {
         return 0;

tests/test_decode_callbacks.c

@@ -37,7 +37,7 @@ bool print_int32(pb_istream_t *stream, const pb_field_t *field, void *arg)
 bool print_fixed32(pb_istream_t *stream, const pb_field_t *field, void *arg)
 {
     uint32_t value;
-    if (!pb_dec_fixed32(stream, NULL, &value))
+    if (!pb_decode_fixed32(stream, &value))
         return false;
     
     printf((char*)arg, (long)value);
@@ -47,7 +47,7 @@ bool print_fixed32(pb_istream_t *stream, const pb_field_t *field, void *arg)
 bool print_fixed64(pb_istream_t *stream, const pb_field_t *field, void *arg)
 {
     uint64_t value;
-    if (!pb_dec_fixed64(stream, NULL, &value))
+    if (!pb_decode_fixed64(stream, &value))
         return false;
     
     printf((char*)arg, (long long)value);

tests/test_encode3.c

@@ -1,40 +1,117 @@
 /* Attempts to test all the datatypes supported by ProtoBuf.
- * Currently only tests the 'required' variety.
  */
 
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <pb_encode.h>
 #include "alltypes.pb.h"
 
-int main()
+int main(int argc, char **argv)
 {
-    /* Initialize the structure with constants */
-    AllTypes alltypes = {
-        1001,
-        1002,
-        1003,
-        1004,
-        1005,
-        1006,
-        true,
-        
-        1008,
-        1009,
-        1010.0f,
-        
-        1011,
-        1012,
-        1013.0,
-        
-        "1014",
-        {4, "1015"},
-        {"1016", 1016},
-        MyEnum_Truth,
-        
-        1099
-    };
+    int mode = (argc > 1) ? atoi(argv[1]) : 0;
     
-    uint8_t buffer[512];
+    /* Initialize the structure with constants */
+    AllTypes alltypes = {0};
+    
+    alltypes.req_int32         = 1001;
+    alltypes.req_int64         = 1002;
+    alltypes.req_uint32        = 1003;
+    alltypes.req_uint64        = 1004;
+    alltypes.req_sint32        = 1005;
+    alltypes.req_sint64        = 1006;
+    alltypes.req_bool          = true;
+    
+    alltypes.req_fixed32       = 1008;
+    alltypes.req_sfixed32      = 1009;
+    alltypes.req_float         = 1010.0f;
+    
+    alltypes.req_fixed64       = 1011;
+    alltypes.req_sfixed64      = 1012;
+    alltypes.req_double        = 1013.0;
+    
+    strcpy(alltypes.req_string, "1014");
+    alltypes.req_bytes.size = 4;
+    memcpy(alltypes.req_bytes.bytes, "1015", 4);
+    strcpy(alltypes.req_submsg.substuff1, "1016");
+    alltypes.req_submsg.substuff2 = 1016;
+    alltypes.req_enum = MyEnum_Truth;
+    
+    alltypes.rep_int32_count = 5; alltypes.rep_int32[4] = 2001;
+    alltypes.rep_int64_count = 5; alltypes.rep_int64[4] = 2002;
+    alltypes.rep_uint32_count = 5; alltypes.rep_uint32[4] = 2003;
+    alltypes.rep_uint64_count = 5; alltypes.rep_uint64[4] = 2004;
+    alltypes.rep_sint32_count = 5; alltypes.rep_sint32[4] = 2005;
+    alltypes.rep_sint64_count = 5; alltypes.rep_sint64[4] = 2006;
+    alltypes.rep_bool_count = 5; alltypes.rep_bool[4] = true;
+    
+    alltypes.rep_fixed32_count = 5; alltypes.rep_fixed32[4] = 2008;
+    alltypes.rep_sfixed32_count = 5; alltypes.rep_sfixed32[4] = 2009;
+    alltypes.rep_float_count = 5; alltypes.rep_float[4] = 2010.0f;
+    
+    alltypes.rep_fixed64_count = 5; alltypes.rep_fixed64[4] = 2011;
+    alltypes.rep_sfixed64_count = 5; alltypes.rep_sfixed64[4] = 2012;
+    alltypes.rep_double_count = 5; alltypes.rep_double[4] = 2013.0;
+    
+    alltypes.rep_string_count = 5; strcpy(alltypes.rep_string[4], "2014");
+    alltypes.rep_bytes_count = 5; alltypes.rep_bytes[4].size = 4;
+    memcpy(alltypes.rep_bytes[4].bytes, "2015", 4);
+
+    alltypes.rep_submsg_count = 5;
+    strcpy(alltypes.rep_submsg[4].substuff1, "2016");
+    alltypes.rep_submsg[4].substuff2 = 2016;
+    alltypes.rep_submsg[4].has_substuff3 = true;
+    alltypes.rep_submsg[4].substuff3 = 2016;
+    
+    alltypes.rep_enum_count = 5; alltypes.rep_enum[4] = MyEnum_Truth;
+    
+    if (mode != 0)
+    {
+        /* Fill in values for optional fields */
+        alltypes.has_opt_int32 = true;
+        alltypes.opt_int32         = 3041;
+        alltypes.has_opt_int64 = true;
+        alltypes.opt_int64         = 3042;
+        alltypes.has_opt_uint32 = true;
+        alltypes.opt_uint32        = 3043;
+        alltypes.has_opt_uint64 = true;
+        alltypes.opt_uint64        = 3044;
+        alltypes.has_opt_sint32 = true;
+        alltypes.opt_sint32        = 3045;
+        alltypes.has_opt_sint64 = true;
+        alltypes.opt_sint64        = 3046;
+        alltypes.has_opt_bool = true;
+        alltypes.opt_bool          = true;
+        
+        alltypes.has_opt_fixed32 = true;
+        alltypes.opt_fixed32       = 3048;
+        alltypes.has_opt_sfixed32 = true;
+        alltypes.opt_sfixed32      = 3049;
+        alltypes.has_opt_float = true;
+        alltypes.opt_float         = 3050.0f;
+        
+        alltypes.has_opt_fixed64 = true;
+        alltypes.opt_fixed64       = 3051;
+        alltypes.has_opt_sfixed64 = true;
+        alltypes.opt_sfixed64      = 3052;
+        alltypes.has_opt_double = true;
+        alltypes.opt_double        = 3053.0;
+        
+        alltypes.has_opt_string = true;
+        strcpy(alltypes.opt_string, "3054");
+        alltypes.has_opt_bytes = true;
+        alltypes.opt_bytes.size = 4;
+        memcpy(alltypes.opt_bytes.bytes, "3055", 4);
+        alltypes.has_opt_submsg = true;
+        strcpy(alltypes.opt_submsg.substuff1, "3056");
+        alltypes.opt_submsg.substuff2 = 3056;
+        alltypes.has_opt_enum = true;
+        alltypes.opt_enum = MyEnum_Truth;
+    }
+    
+    alltypes.end = 1099;
+    
+    uint8_t buffer[1024];
     pb_ostream_t stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
     
     /* Now encode it and check if we succeeded. */
@@ -45,6 +122,7 @@ int main()
     }
     else
     {
+        fprintf(stderr, "Encoding failed!\n");
         return 1; /* Failure */
     }
 }

tests/test_missing_fields.c

@@ -27,7 +27,7 @@ int main()
         
         if (!pb_decode(&stream, MissingField_fields, &msg))
         {
-            printf("Decode failed.\n");
+            printf("Decode failed: %s\n", PB_GET_ERROR(&stream));
             return 2;
         }
     }