Add <ctypedef> annotation to import structs from C without typedef

lib/C/locale.nelua

@@ -1,14 +1,8 @@
 require 'C'
 
-##[[
-cinclude '<locale.h>'
+## cinclude '<locale.h>'
 
-cemitdecl([==[
-typedef struct lconv lconv_t;
-]==])
-]]
-
-global lconv <cimport'lconv_t',nodecl> = @record {
+global lconv <cimport'lconv_t',nodecl,ctypedef> = @record {
   decimal_point: cstring,
   thousands_sep: cstring,
   grouping: cstring,

lib/C/time.nelua

@@ -2,18 +2,12 @@ require 'C'
 
 ##[[
 cinclude '<time.h>'
-
-cemitdecl([==[
-typedef struct tm tm_t;
-typedef struct timespec timespec_t;
-]==])
-
 local neluatypes = require 'nelua.types'
 ]]
 
 global clock_t <cimport'clock_t',nodecl> = #[neluatypes.IntegralType('clock_t', primtypes.clong.size)]#
 global time_t <cimport'time_t',nodecl> = #[neluatypes.IntegralType('time_t', primtypes.clong.size)]#
-global tm <cimport'tm_t',nodecl> = @record{
+global tm <cimport'tm',nodecl,ctypedef> = @record{
   tm_sec: cint,
   tm_min: cint,
   tm_hour: cint,
@@ -24,7 +18,7 @@ global tm <cimport'tm_t',nodecl> = @record{
   tm_yday: cint,
   tm_isdst: cint
 }
-global timespec <cimport'timespec_t',nodecl> = @record {
+global timespec <cimport'timespec',nodecl,ctypedef> = @record {
   tv_sec: time_t,
   tv_nsec: clong
 }

lib/os.nelua

@@ -3,16 +3,10 @@ require 'string'
 --------------------------------------------------------------------------------
 -- C imports
 
-##[[
-cemitdecl([==[
-typedef struct tm tm_t;
-]==])
-]]
-
 local clock_t <cimport,nodecl> = #[types.IntegralType('clock_t', primtypes.clong.size)]#
 local time_t <cimport,nodecl> = #[types.IntegralType('time_t', primtypes.clong.size)]#
 
-local tm <cimport'tm_t',nodecl> = @record {
+local tm <cimport'tm',nodecl,ctypedef> = @record {
   tm_year: cint,
   tm_mon: cint,
   tm_mday: cint,

nelua/ccontext.lua

@@ -72,15 +72,28 @@ function CContext:typename(type)
   until visitor
 
   if visitor then
-    if config.check_type_shape then
-      assert(type:shape())
-    end
-    if type.cinclude then -- include headers before declaring
-      self:add_include(type.cinclude)
-    end
-    if not type.nodecl and not self:is_declared(type.codename) then
+    if not self:is_declared(type.codename) then
+      self.declarations[type.codename] = true
+      if config.check_type_shape then
+        assert(type:shape())
+      end
+      if type.cinclude then -- include headers before declaring
+        self:add_include(type.cinclude)
+      end
       -- only declare when needed
-      visitor(self, type)
+      if not type.nodecl then
+        visitor(self, type)
+      elseif type.ctypedef then
+        local kind
+        if type.is_record then kind = 'struct'
+        elseif type.is_union then kind = 'union'
+        elseif type.is_enum then kind = 'enum'
+        end
+        if kind then
+          local code = 'typedef '..kind..' '..type.codename..' '..type.codename..';\n'
+          table.insert(self.declarations, code)
+        end
+      end
     end
   end
   return type.codename

nelua/cgenerator.lua

@@ -261,11 +261,10 @@ typevisitors[types.ArrayType] = function(context, type)
   decemitter:add_ln(';')
   decemitter:add_ln('nelua_static_assert(sizeof(',type.codename,') == ', type.size,
                     ', "Nelua and C disagree on type size");')
-  context:add_declaration(decemitter:generate(), type.codename)
+  table.insert(context.declarations, decemitter:generate())
 end
 
 typevisitors[types.PointerType] = function(context, type)
-  context.declarations[type.codename] = true
   local decemitter = CEmitter(context, 0)
   local index = nil
   if type.subtype.is_record and not type.subtype.nodecl and not context.declarations[type.subtype.codename] then
@@ -284,7 +283,6 @@ typevisitors[types.PointerType] = function(context, type)
 end
 
 typevisitors[types.RecordType] = function(context, type)
-  context.declarations[type.codename] = true
   local decemitter = CEmitter(context, 0)
   decemitter:add_ln('typedef struct ', type.codename, ' ', type.codename, ';')
   table.insert(context.declarations, decemitter:generate())
@@ -317,7 +315,7 @@ end
 typevisitors[types.EnumType] = function(context, type)
   local decemitter = CEmitter(context, 0)
   decemitter:add_ln('typedef ', type.subtype, ' ', type.codename, ';')
-  context:add_declaration(decemitter:generate(), type.codename)
+  table.insert(context.declarations, decemitter:generate())
 end
 
 typevisitors[types.FunctionType] = function(context, type)
@@ -330,7 +328,7 @@ typevisitors[types.FunctionType] = function(context, type)
     decemitter:add(argtype)
   end
   decemitter:add_ln(');')
-  context:add_declaration(decemitter:generate(), type.codename)
+  table.insert(context.declarations, decemitter:generate())
 end
 
 typevisitors.FunctionReturnType = function(context, functype)

nelua/typedefs.lua

@@ -257,6 +257,8 @@ typedefs.type_annots = {
   -- Whether to skip declaring the type in C.
   -- When using this, the type must be declared somewhere else, like in a C include.
   nodecl = true,
+  -- Whether to emit typedef for a C imported structs.
+  ctypedef = true,
   -- Whether the compiler should pack a record type, removing padding between fields.
   -- It uses the '__attribute__((packed))' in C.
   packed = true,

nelua/types.lua

@@ -76,6 +76,8 @@ Type.shape = shaper.shape {
   nodecl = shaper.optional_boolean,
   -- Whether the code generator should import the type from C.
   cimport = shaper.optional_boolean,
+  -- Whether to emit typedef for a C imported structs.
+  ctypedef = shaper.optional_boolean,
   -- Marked when declaring a type without its definition.
   forwarddecl = shaper.optional_boolean,
   -- C header that the code generator should include when using the type.

spec/05-cgenerator_spec.lua

@@ -2355,6 +2355,10 @@ it("annotations", function()
   assert.generate_c(
     "local function puts(s: cstring): int32 <cimport'puts'> end",
     "int32_t puts(char* s);")
+  assert.generate_c([[
+    global timespec <cimport'timespec',nodecl,ctypedef> = @record{tv_sec: clong, tv_nsec: clong}
+    local t: timespec
+  ]], "typedef struct timespec timespec;")
   assert.generate_c(
     "local function cos(x: number): number <cimport'myfunc',cinclude'<myheader.h>',nodecl> end",
     "#include <myheader.h>")