From ba97926cfd1e82bd294cf5e484633850d8e0b368 Mon Sep 17 00:00:00 2001
From: Bernhard Krämer <bdkrae@gmail.com>
Date: Sun, 9 Oct 2016 20:26:28 +0200
Subject: Add proto3 option to handle singular fields

---
 generator/nanopb_generator.py | 12 +++++++-----
 generator/proto/nanopb.proto  |  3 +++
 pb.h                          | 13 +++++++++++++
 pb_decode.c                   |  3 ++-
 4 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/generator/nanopb_generator.py b/generator/nanopb_generator.py
index 973c7610..185a97bb 100755
--- a/generator/nanopb_generator.py
+++ b/generator/nanopb_generator.py
@@ -258,16 +258,18 @@ class Field:
 
         # Check field rules, i.e. required/optional/repeated.
         can_be_static = True
-        if desc.label == FieldD.LABEL_REQUIRED:
-            self.rules = 'REQUIRED'
-        elif desc.label == FieldD.LABEL_OPTIONAL:
-            self.rules = 'OPTIONAL'
-        elif desc.label == FieldD.LABEL_REPEATED:
+        if desc.label == FieldD.LABEL_REPEATED:
             self.rules = 'REPEATED'
             if self.max_count is None:
                 can_be_static = False
             else:
                 self.array_decl = '[%d]' % self.max_count
+        elif field_options.HasField("proto3"):
+            self.rules = 'SINGULAR'
+        elif desc.label == FieldD.LABEL_REQUIRED:
+            self.rules = 'REQUIRED'
+        elif desc.label == FieldD.LABEL_OPTIONAL:
+            self.rules = 'OPTIONAL'
         else:
             raise NotImplementedError(desc.label)
 
diff --git a/generator/proto/nanopb.proto b/generator/proto/nanopb.proto
index 8aab19a1..b9961c88 100644
--- a/generator/proto/nanopb.proto
+++ b/generator/proto/nanopb.proto
@@ -66,6 +66,9 @@ message NanoPBOptions {
 
   // decode oneof as anonymous union
   optional bool anonymous_oneof = 11 [default = false];
+
+  // Proto3 singular field does not generate a "has_" flag
+  optional bool proto3 = 12 [default = false];
 }
 
 // Extensions to protoc 'Descriptor' type in order to define options
diff --git a/pb.h b/pb.h
index 4576f79a..0e1e92d5 100644
--- a/pb.h
+++ b/pb.h
@@ -413,6 +413,10 @@ struct pb_extension_s {
     pb_delta(st, has_ ## m, m), \
     pb_membersize(st, m), 0, ptr}
 
+#define PB_SINGULAR_STATIC(tag, st, m, fd, ltype, ptr) \
+    {tag, PB_ATYPE_STATIC | PB_HTYPE_OPTIONAL | ltype, \
+    fd, 0, pb_membersize(st, m), 0, ptr}
+
 /* Repeated fields have a _count field and also the maximum number of entries. */
 #define PB_REPEATED_STATIC(tag, st, m, fd, ltype, ptr) \
     {tag, PB_ATYPE_STATIC | PB_HTYPE_REPEATED | ltype, \
@@ -444,6 +448,11 @@ struct pb_extension_s {
     {tag, PB_ATYPE_POINTER | PB_HTYPE_OPTIONAL | ltype, \
     fd, 0, pb_membersize(st, m[0]), 0, ptr}
 
+/* Same as optional fields*/
+#define PB_SINGULAR_POINTER(tag, st, m, fd, ltype, ptr) \
+    {tag, PB_ATYPE_POINTER | PB_HTYPE_OPTIONAL | ltype, \
+    fd, 0, pb_membersize(st, m[0]), 0, ptr}
+
 /* Repeated fields have a _count field and a pointer to array of pointers */
 #define PB_REPEATED_POINTER(tag, st, m, fd, ltype, ptr) \
     {tag, PB_ATYPE_POINTER | PB_HTYPE_REPEATED | ltype, \
@@ -458,6 +467,10 @@ struct pb_extension_s {
 #define PB_OPTIONAL_CALLBACK(tag, st, m, fd, ltype, ptr) \
     {tag, PB_ATYPE_CALLBACK | PB_HTYPE_OPTIONAL | ltype, \
     fd, 0, pb_membersize(st, m), 0, ptr}
+
+#define PB_SINGULAR_CALLBACK(tag, st, m, fd, ltype, ptr) \
+    {tag, PB_ATYPE_CALLBACK | PB_HTYPE_OPTIONAL | ltype, \
+    fd, 0, pb_membersize(st, m), 0, ptr}
     
 #define PB_REPEATED_CALLBACK(tag, st, m, fd, ltype, ptr) \
     {tag, PB_ATYPE_CALLBACK | PB_HTYPE_REPEATED | ltype, \
diff --git a/pb_decode.c b/pb_decode.c
index 7a4e29a8..1f6aeae0 100644
--- a/pb_decode.c
+++ b/pb_decode.c
@@ -360,7 +360,8 @@ static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t
             return func(stream, iter->pos, iter->pData);
             
         case PB_HTYPE_OPTIONAL:
-            *(bool*)iter->pSize = true;
+            if (iter->pSize != iter->pData)
+                *(bool*)iter->pSize = true;
             return func(stream, iter->pos, iter->pData);
     
         case PB_HTYPE_REPEATED:
-- 
cgit 1.2.3-korg


From ee44d0cee9fa87891fdc5371578f6ff3974a8d59 Mon Sep 17 00:00:00 2001
From: Bernhard Krämer <bdkrae@gmail.com>
Date: Sun, 9 Oct 2016 20:27:28 +0200
Subject: Prevent fields with default value from encoding when proto3 option is
 set

---
 pb_encode.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/pb_encode.c b/pb_encode.c
index 4685614c..4f57fa5f 100644
--- a/pb_encode.c
+++ b/pb_encode.c
@@ -210,6 +210,23 @@ static bool checkreturn encode_basic_field(pb_ostream_t *stream,
     
     if (field->size_offset)
         pSize = (const char*)pData + field->size_offset;
+    else if (!field->size_offset && PB_HTYPE(field->type) == PB_HTYPE_OPTIONAL)
+    {
+        /* In proto3 there are optional fields but no has_ flag, do not encode this fields 
+         * when value is default or empty. */
+        if(PB_LTYPE(field->type) == PB_LTYPE_BYTES){
+            const pb_bytes_array_t *bytes = (const pb_bytes_array_t*)pData;
+            if(bytes->size == 0)
+                implicit_has = false;
+        else if ((PB_LTYPE(field->type) == PB_LTYPE_STRING && *(const char*)pData == '\0') ||
+                (field->data_size == sizeof(uint_least8_t) && *(const uint_least8_t*)pData == 0) ||
+                (field->data_size == sizeof(uint_least16_t) && *(const uint_least16_t*)pData == 0) ||
+                (field->data_size == sizeof(uint32_t) && *(const uint_least32_t*)pData == 0) ||
+                (field->data_size == sizeof(uint64_t) && *(const uint_least64_t*)pData == 0))                   
+            implicit_has = false;
+        }
+        pSize = &implicit_has;
+    }
     else
         pSize = &implicit_has;
 
-- 
cgit 1.2.3-korg