8 files changed, 35 insertions, 33 deletions

diff --git a/docs/concepts.rst b/docs/concepts.rst
index d3261146..355af25e 100644
--- a/docs/concepts.rst
+++ b/docs/concepts.rst
@@ -92,9 +92,8 @@ Writing to stdout::
 
 Input streams
 -------------
-For input streams, there are a few extra rules:
+For input streams, there is one extra rule:
 
-#) If buf is NULL, read from stream but don't store the data. This is used to skip unknown input.
 #) You don't need to know the length of the message in advance. After getting EOF error when reading, set bytes_left to 0 and return false. Pb_decode will detect this and if the EOF was in a proper position, it will return true.
 
 Here is the structure::
diff --git a/example/common.c b/example/common.c
index b27ccae2..04a5aa85 100644
--- a/example/common.c
+++ b/example/common.c
@@ -19,15 +19,6 @@ static bool read_callback(pb_istream_t *stream, uint8_t *buf, size_t count)
     int fd = (intptr_t)stream->state;
     int result;
     
-    if (buf == NULL)
-    {
-        /* Well, this is a really inefficient way to skip input. */
-        /* It is only used when there are unknown fields. */
-        char dummy;
-        while (count-- && recv(fd, &dummy, 1, 0) == 1);
-        return count == 0;
-    }
-    
     result = recv(fd, buf, count, MSG_WAITALL);
     
     if (result == 0)
diff --git a/pb_decode.c b/pb_decode.c
index 86dec4b7..8e01fd7a 100644
--- a/pb_decode.c
+++ b/pb_decode.c
@@ -36,26 +36,41 @@ static const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT] = {
  * pb_istream *
  **************/
 
-bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
+static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count)
 {
-    if (stream->bytes_left < count)
-        PB_RETURN_ERROR(stream, "end-of-stream");
+    uint8_t *source = (uint8_t*)stream->state;
     
-    if (!stream->callback(stream, buf, count))
-        PB_RETURN_ERROR(stream, "io error");
+    if (buf != NULL)
+        memcpy(buf, source, count);
     
-    stream->bytes_left -= count;
+    stream->state = source + count;
     return true;
 }
 
-static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count)
+bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
 {
-    uint8_t *source = (uint8_t*)stream->state;
+	if (buf == NULL && stream->callback != buf_read)
+	{
+		/* Skip input bytes */
+		uint8_t tmp[16];
+		while (count > 16)
+		{
+			if (!pb_read(stream, tmp, 16))
+				return false;
+			
+			count -= 16;
+		}
+		
+		return pb_read(stream, tmp, count);
+	}
+
+    if (stream->bytes_left < count)
+        PB_RETURN_ERROR(stream, "end-of-stream");
     
-    if (buf != NULL)
-        memcpy(buf, source, count);
+    if (!stream->callback(stream, buf, count))
+        PB_RETURN_ERROR(stream, "io error");
     
-    stream->state = source + count;
+    stream->bytes_left -= count;
     return true;
 }
 
diff --git a/pb_decode.h b/pb_decode.h
index 483665ee..2be92050 100644
--- a/pb_decode.h
+++ b/pb_decode.h
@@ -19,12 +19,10 @@
  * 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.
  */
diff --git a/tests/Makefile b/tests/Makefile
index 9b02817f..73efbe63 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -70,6 +70,9 @@ run_unittests: decode_unittests encode_unittests test_cxxcompile test_encode1 te
 	[ "`./test_encode2 | ./test_decode2`" = \
 	"`./test_encode2 | protoc --decode=Person -I. -I../generator -I/usr/include person.proto`" ]
 	
+	[ "`./test_decode2 < person_with_extra_field.pb`" = \
+	"`cat person_with_extra_field.txt`" ]
+	
 	[ "`./test_encode_callbacks | ./test_decode_callbacks`" = \
 	"`./test_encode_callbacks | protoc --decode=TestMessage callbacks.proto`" ]
 
diff --git a/tests/person_with_extra_field.pb b/tests/person_with_extra_field.pb
new file mode 100644
index 00000000..00d153cb
--- /dev/null
+++ b/tests/person_with_extra_field.pb
diff --git a/tests/person_with_extra_field.txt b/tests/person_with_extra_field.txt
new file mode 100644
index 00000000..fae9f87d
--- /dev/null
+++ b/tests/person_with_extra_field.txt
@@ -0,0 +1,3 @@
+name: "Test Person 99"
+id: 99
+email: "test@person.com"
diff --git a/tests/test_decode2.c b/tests/test_decode2.c
index 762b2b3f..2142977e 100644
--- a/tests/test_decode2.c
+++ b/tests/test_decode2.c
@@ -59,13 +59,6 @@ bool callback(pb_istream_t *stream, uint8_t *buf, size_t count)
     FILE *file = (FILE*)stream->state;
     bool status;
     
-    if (buf == NULL)
-    {
-       /* Skipping data */
-        while (count-- && fgetc(file) != EOF);
-        return count == 0;
-    }
-    
     status = (fread(buf, 1, count, file) == count);
     
     if (feof(file))