X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=pb_encode.c;h=cd731dcf5df7d245d6e4275b632b9059091c89f5;hb=07375a126337916f3a34ea94f8085b8f89d789a1;hp=4685614cf70ea2f70e49b5954b437cba1a861707;hpb=62afd54964528c1fbd5ab802134f7e9ad912d904;p=apps%2Fagl-service-can-low-level.git

diff --git a/pb_encode.c b/pb_encode.c
index 4685614c..cd731dcf 100644
--- a/pb_encode.c
+++ b/pb_encode.c
@@ -35,6 +35,7 @@ static bool checkreturn pb_enc_fixed64(pb_ostream_t *stream, const pb_field_t *f
 static bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src);
 static bool checkreturn pb_enc_string(pb_ostream_t *stream, const pb_field_t *field, const void *src);
 static bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field, const void *src);
+static bool checkreturn pb_enc_fixed_length_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src);
 
 /* --- Function pointers to field encoders ---
  * Order in the array must match pb_action_t LTYPE numbering.
@@ -50,7 +51,7 @@ static const pb_encoder_t PB_ENCODERS[PB_LTYPES_COUNT] = {
     &pb_enc_string,
     &pb_enc_submessage,
     NULL, /* extensions */
-    &pb_enc_bytes /* PB_LTYPE_FIXED_LENGTH_BYTES */
+    &pb_enc_fixed_length_bytes
 };
 
 /*******************************
@@ -59,11 +60,12 @@ static const pb_encoder_t PB_ENCODERS[PB_LTYPES_COUNT] = {
 
 static bool checkreturn buf_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count)
 {
+    size_t i;
     pb_byte_t *dest = (pb_byte_t*)stream->state;
     stream->state = dest + count;
     
-    while (count--)
-        *dest++ = *buf++;
+    for (i = 0; i < count; i++)
+        dest[i] = buf[i];
     
     return true;
 }
@@ -197,21 +199,75 @@ static bool checkreturn encode_array(pb_ostream_t *stream, const pb_field_t *fie
     return true;
 }
 
+/* In proto3, all fields are optional and are only encoded if their value is "non-zero".
+ * This function implements the check for the zero value. */
+static bool pb_check_proto3_default_value(const pb_field_t *field, const void *pData)
+{
+    if(PB_LTYPE(field->type) == PB_LTYPE_BYTES)
+    {
+        const pb_bytes_array_t *bytes = (const pb_bytes_array_t*)pData;
+        return bytes->size == 0;
+    }
+    else if (PB_LTYPE(field->type) == PB_LTYPE_STRING)
+    {
+        return *(const char*)pData == '\0';
+    }
+    else if (PB_LTYPE(field->type) == PB_LTYPE_FIXED_LENGTH_BYTES)
+    {
+        /* Fixed length bytes is only empty if its length is fixed
+         * as 0. Which would be pretty strange, but we can check
+         * it anyway. */
+        return field->data_size == 0;
+    }
+	else
+	{
+	    /* PB_LTYPE_VARINT, UVARINT, SVARINT, FIXED32, FIXED64,
+	     * SUBMESSAGE, EXTENSION: These all have integer or pointer
+	     * value which can be compared with 0. This does the check
+	     * byte-by-byte to avoid the switch-cast logic used in
+	     * pb_enc_varint(). (Casting to char* is safe with regards
+	     * to C strict aliasing rules.)
+	     */
+	    uint_fast8_t i;
+	    const char *p = (const char*)pData;
+	    for (i = 0; i < field->data_size; i++)
+	    {
+	        if (p[i] != 0)
+	        {
+	            return false;
+	        }
+	    }
+
+	    return true;
+	}
+}
+
 /* Encode a field with static or pointer allocation, i.e. one whose data
  * is available to the encoder directly. */
 static bool checkreturn encode_basic_field(pb_ostream_t *stream,
     const pb_field_t *field, const void *pData)
 {
     pb_encoder_t func;
-    const void *pSize;
-    bool implicit_has = true;
+    bool implicit_has;
+    const void *pSize = &implicit_has;
     
     func = PB_ENCODERS[PB_LTYPE(field->type)];
     
     if (field->size_offset)
+    {
+        /* Static optional, repeated or oneof field */
         pSize = (const char*)pData + field->size_offset;
+    }
+    else if (PB_HTYPE(field->type) == PB_HTYPE_OPTIONAL)
+    {
+        /* Proto3 style field, optional but without explicit has_ field. */
+        implicit_has = !pb_check_proto3_default_value(field, pData);
+    }
     else
-        pSize = &implicit_has;
+    {
+        /* Required field, always present */
+        implicit_has = true;
+    }
 
     if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
     {
@@ -219,7 +275,6 @@ static bool checkreturn encode_basic_field(pb_ostream_t *stream,
          * the data. If the 2nd pointer is NULL, it is interpreted as if
          * the has_field was false.
          */
-        
         pData = *(const void* const*)pData;
         implicit_has = (pData != NULL);
     }
@@ -640,9 +695,6 @@ static bool checkreturn pb_enc_bytes(pb_ostream_t *stream, const pb_field_t *fie
 {
     const pb_bytes_array_t *bytes = NULL;
 
-    if (PB_LTYPE(field->type) == PB_LTYPE_FIXED_LENGTH_BYTES)
-        return pb_encode_string(stream, (const pb_byte_t*)src, field->data_size);
-
     bytes = (const pb_bytes_array_t*)src;
     
     if (src == NULL)
@@ -694,3 +746,8 @@ static bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t
     return pb_encode_submessage(stream, (const pb_field_t*)field->ptr, src);
 }
 
+static bool checkreturn pb_enc_fixed_length_bytes(pb_ostream_t *stream, const pb_field_t *field, const void *src)
+{
+    return pb_encode_string(stream, (const pb_byte_t*)src, field->data_size);
+}
+