A good start on upb_encode and upb_decode.

1 files changed, 111 insertions, 28 deletions

diff --git a/tools/make_c_api.lua b/tools/make_c_api.lua
index aaf5d1e..62fd370 100644
--- a/tools/make_c_api.lua
+++ b/tools/make_c_api.lua
@@ -47,7 +47,6 @@ local function to_preproc(...)
   return string.upper(to_cident(...))
 end
 
-
 -- Strips away last path element, ie:
 --   foo.Bar.Baz -> foo.Bar
 local function remove_name(name)
@@ -60,6 +59,10 @@ local function remove_name(name)
   return string.sub(name, 1, package_end)
 end
 
+local function enum_value_symbol(enumdef, name)
+  return to_cident(remove_name(enumdef:full_name())) .. "_" .. name
+end
+
 local function dump_enum_vals(enumdef, append)
   local enum_vals = {}
 
@@ -96,7 +99,7 @@ local function dump_enum_vals(enumdef, append)
   local cident = to_cident(remove_name(enumdef:full_name()))
   for i, pair in ipairs(enum_vals) do
     k, v = pair[1], pair[2]
-    append('  %s = %d', cident .. "_" .. k, v)
+    append('  %s = %d', enum_value_symbol(enumdef, k), v)
     if i == #enum_vals then
       append('\n')
     else
@@ -105,6 +108,20 @@ local function dump_enum_vals(enumdef, append)
   end
 end
 
+local function field_default(field)
+  if field:type() == upb.TYPE_MESSAGE then
+    return "NULL"
+  elseif field:type() == upb.TYPE_STRING or
+         field:type() == upb.TYPE_BYTES then
+    local default = field:default() or ""
+    return string.format('upb_stringview_make("%s", strlen("%s"))', field:default(), field:default())
+  elseif field:type() == upb.TYPE_ENUM then
+    return enum_value_symbol(field:subdef(), field:default())
+  else
+    return field:default();
+  end
+end
+
 local function ctype(field)
   if field:label() == upb.LABEL_REPEATED then
     return "upb_array*"
@@ -134,19 +151,18 @@ end
 local function field_layout_rank(field)
   -- Order:
   --   1, 2, 3. primitive fields (8, 4, 1 byte)
-  --   4. oneof fields
-  --   5. string fields
-  --   6. submessage fields
-  --   7. repeated fields
+  --   4. string fields
+  --   5. submessage fields
+  --   6. repeated fields
   local rank
   if field:containing_oneof() then
-    rank = 4
+    rank = 100  -- These go last (actually we skip them).
   elseif field:label() == upb.LABEL_REPEATED then
-    rank = 7
-  elseif field:type() == upb.TYPE_MESSAGE then
     rank = 6
-  elseif field:type() == upb.TYPE_STRING or field:type() == upb.TYPE_BYTES then
+  elseif field:type() == upb.TYPE_MESSAGE then
     rank = 5
+  elseif field:type() == upb.TYPE_STRING or field:type() == upb.TYPE_BYTES then
+    rank = 4
   elseif field:type() == upb.TYPE_BOOL then
     rank = 3
   elseif field:type() == upb.TYPE_FLOAT or
@@ -257,6 +273,8 @@ local function write_c_file(filedef, hfilename, append)
   emit_file_warning(filedef, append)
 
   append('#include <stddef.h>\n')
+  append('#include "upb/decode.h"\n\n')
+  append('#include "upb/encode.h"\n\n')
   append('#include "upb/msg.h"\n')
   append('#include "upb/upb.h"\n')
   append('#include "%s"\n\n', hfilename)
@@ -273,13 +291,29 @@ local function write_c_file(filedef, hfilename, append)
 
     local fields_array_ref = "NULL"
     local submsgs_array_ref = "NULL"
+    local oneofs_array_ref = "NULL"
     local field_count = 0
     local submsg_count = 0
     local submsg_set = {}
     local submsg_indexes = {}
     local hasbit_count = 0
     local hasbit_indexes = {}
-    -- TODO(haberman): oneofs
+    local oneof_count = 0
+    local oneof_indexes = {}
+
+    -- Create a layout order for oneofs.
+    local oneofs_layout_order = {}
+    for oneof in msg:oneofs() do
+      table.insert(oneofs_layout_order, oneof)
+    end
+    table.sort(oneofs_layout_order, function(a, b)
+      return a:name() < b:name()
+    end)
+
+    for _, oneof in ipairs(oneofs_layout_order) do
+      oneof_indexes[oneof] = oneof_count
+      oneof_count = oneof_count + 1
+    end
 
     -- Create a layout order for fields.  We use this order for the struct and
     -- for offsets, but our list of fields we keep in field number order.
@@ -301,6 +335,8 @@ local function write_c_file(filedef, hfilename, append)
     end)
 
     append('struct %s {\n', msgname)
+
+    -- Non-oneof fields.
     for _, field in ipairs(fields_layout_order) do
       field_count = field_count + 1
 
@@ -309,15 +345,46 @@ local function write_c_file(filedef, hfilename, append)
         submsg_set[field:subdef()] = true
       end
 
-      if has_hasbit(field) then
-        hasbit_indexes[field] = hasbit_count
-        hasbit_count = hasbit_count + 1
+      if field:containing_oneof() then
+        -- Do nothing now
+      else
+        if has_hasbit(field) then
+          hasbit_indexes[field] = hasbit_count
+          hasbit_count = hasbit_count + 1
+        end
+
+        append('  %s %s;\n', ctype(field), field:name())
       end
+    end
 
-      append('  %s %s;\n', ctype(field), field:name())
+    local oneof_last_fields = {}
+    -- Oneof fields.
+    for oneof in msg:oneofs() do
+      local fullname = to_cident(oneof:containing_type():full_name() .. "." .. oneof:name())
+      append('  union {\n')
+      oneof_last_fields[oneof] = ""
+      for field in oneof:fields() do
+        oneof_last_fields[oneof] = field:name()
+        append('    %s %s;\n', ctype(field), field:name())
+      end
+      append('  } %s;\n', oneof:name())
+      append('  %s_oneofcases %s_case;\n', fullname, oneof:name())
     end
+
     append('};\n\n')
 
+    if oneof_count > 0 then
+      local oneofs_array_name = msgname .. "_oneofs"
+      oneofs_array_ref = "&" .. oneofs_array_name .. "[0]"
+      append('static const upb_msglayout_oneofinit_v1 %s[%s] = {\n',
+             oneofs_array_name, oneof_count)
+      for _, oneof in ipairs(oneofs_layout_order) do
+        append('  {offsetof(%s, %s), offsetof(%s, %s_case)},\n',
+               msgname, oneof:name(), msgname, oneof:name())
+      end
+      append('};\n\n')
+    end
+
     if submsg_count > 0 then
       -- TODO(haberman): could save a little bit of space by only generating a
       -- "submsgs" array for every strongly-connected component.
@@ -354,11 +421,14 @@ local function write_c_file(filedef, hfilename, append)
         if field:type() == upb.TYPE_MESSAGE then
           submsg_index = submsg_indexes[field:subdef()]
         end
+        if field:containing_oneof() then
+          oneof_index = oneof_indexes[field:containing_oneof()]
+        end
         -- TODO(haberman): oneofs.
         append('  {%s, offsetof(%s, %s), %s, %s, %s, %s, %s},\n',
                field:number(),
                msgname,
-               field:name(),
+               (field:containing_oneof() and field:containing_oneof():name()) or field:name(),
                hasbit_indexes[field] or "-1",
                oneof_index,
                submsg_index,
@@ -371,7 +441,7 @@ local function write_c_file(filedef, hfilename, append)
     append('const upb_msglayout_msginit_v1 %s_msginit = {\n', msgname)
     append('  %s,\n', submsgs_array_ref)
     append('  %s,\n', fields_array_ref)
-    append('  NULL, /* TODO. oneofs */\n')
+    append('  %s,\n', oneofs_array_ref)
     append('  NULL, /* TODO. default_msg */\n')
     append('  UPB_ALIGNED_SIZEOF(%s), %s, %s, %s, %s\n',
            msgname, field_count,
@@ -390,36 +460,49 @@ local function write_c_file(filedef, hfilename, append)
 
     append('%s *%s_parsenew(upb_stringview buf, upb_env *env) {\n',
            msgname, msgname)
-    append('  UPB_UNUSED(buf);\n')
-    append('  UPB_UNUSED(env);\n')
-    append('  return NULL;\n')
+    append('  %s *msg = %s_new(env);\n', msgname, msgname)
+    append('  if (upb_decode(buf, msg, &%s_msginit, env)) {\n', msgname)
+    append('    return msg;\n')
+    append('  } else {\n')
+    append('    return NULL;\n')
+    append('  }\n')
     append('}\n')
 
     append('char *%s_serialize(%s *msg, upb_env *env, size_t *size) {\n',
            msgname, msgname)
-    append('  UPB_UNUSED(msg);\n')
-    append('  UPB_UNUSED(env);\n')
-    append('  UPB_UNUSED(size);\n')
-    append('  return NULL; /* TODO. */\n')
+    append('  return upb_encode(msg, &%s_msginit, env, size);\n', msgname)
     append('}\n')
 
     for field in msg:fields() do
       local typename = ctype(field)
       append('%s %s_%s(const %s *msg) {\n',
              typename, msgname, field:name(), msgname);
-      append('  return msg->%s;\n', field:name())
+      if field:containing_oneof() then
+        local oneof = field:containing_oneof()
+        append('  return msg->%s_case == %s ? msg->%s.%s : %s;\n',
+               oneof:name(), field:number(), oneof:name(), field:name(),
+               field_default(field))
+      else
+        append('  return msg->%s;\n', field:name())
+      end
       append('}\n')
       append('void %s_set_%s(%s *msg, %s value) {\n',
              msgname, field:name(), msgname, typename);
-      append('  msg->%s = value;\n', field:name())
+      if field:containing_oneof() then
+        local oneof = field:containing_oneof()
+        append('  msg->%s.%s = value;\n', oneof:name(), field:name())
+        append('  msg->%s_case = %s;\n', oneof:name(), field:number())
+      else
+        append('  msg->%s = value;\n', field:name())
+      end
       append('}\n')
     end
 
     for oneof in msg:oneofs() do
       local fullname = to_cident(oneof:containing_type():full_name() .. "." .. oneof:name())
       append('%s_oneofcases %s_case(const %s *msg) {\n', fullname, fullname, msgname)
-      append('  return 0;  /* TODO. */')
-      append('}')
+      append('  return msg->%s_case;\n', oneof:name())
+      append('}\n')
     end
   end
 end