src/ffi/light_c.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2012-2014 Alexis Laferrière <alexis.laf@xymus.net>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # Support for nesting C code within a Nit program using its FFI
  18 module light_c
  19
  20 import modelize::modelize_property
  21
  22 import light_ffi_base
  23
  24 redef class FFILanguageAssignationPhase
  25         var c_language: FFILanguage = new CLanguage(self)
  26 end
  27
  28 class CLanguage
  29         super FFILanguage
  30
  31         redef fun identify_language(n) do return n.is_c
  32
  33         redef fun compile_module_block(block, ecc, mmodule)
  34         do
  35                 if block.is_c_header then
  36                         ecc.header_custom.add block.location.as_line_pragma
  37                         ecc.header_custom.add "\n"
  38                         ecc.header_custom.add block.code
  39                 else if block.is_c_body then
  40                         ecc.body_impl.add block.location.as_line_pragma
  41                         ecc.body_impl.add "\n"
  42                         ecc.body_impl.add block.code
  43                 end
  44         end
  45
  46         redef fun compile_extern_method(block, m, ecc, mmodule)
  47         do
  48                 var fc = new ExternCFunction(m, mmodule)
  49                 fc.decls.add( block.location.as_line_pragma )
  50                 fc.exprs.add( block.code )
  51                 ecc.body_impl.add fc.to_writer
  52         end
  53
  54         redef fun compile_extern_class(block, m, ecc, mmodule) do end
  55
  56         redef fun get_ftype(block, m) do return new ForeignCType(block.code)
  57 end
  58
  59 redef class AExternCodeBlock
  60         fun is_c: Bool do return language_name == null or
  61                 language_name_lowered == "c" or language_name_lowered.has_prefix( "c " )
  62
  63         fun is_c_body: Bool do return language_name == null or
  64                 language_name_lowered == "c" or language_name_lowered ==  "c body"
  65
  66         fun is_c_header: Bool do return language_name_lowered == "c header"
  67 end
  68
  69 redef class Location
  70         fun as_line_pragma: String do return "#line {line_start-1} \"{file.filename}\"\n"
  71 end
  72
  73 redef class MModule
  74         # FIXME make nullable the key of `cflags`, `ldflags` and `cppflags` when
  75         # supported by the bootstrap
  76
  77         # Custom options for the C compiler (CFLAGS)
  78         var cflags = new MultiHashMap[String, String]
  79
  80         # Custom options for the C linker (LDFLAGS)
  81         var ldflags = new MultiHashMap[String, String]
  82
  83         # Additional libraries needed for the compilation
  84         # Will be used with pkg-config
  85         var pkgconfigs = new Array[String]
  86 end
  87
  88 class ForeignCType
  89         super ForeignType
  90
  91         redef var ctype: String
  92 end
  93
  94 # Context when calling user C code from generated code
  95 fun to_c_call_context: ToCCallContext do return once new ToCCallContext
  96
  97 # Context when calling generated code from user C code
  98 fun from_c_call_context: FromCCallContext do return once new FromCCallContext
  99
 100 # Context when calling user C code from generated code
 101 class ToCCallContext
 102         super CallContext
 103
 104         # TODO: private init because singleton instance (see `to_c_call_context`)
 105
 106         redef fun name_mtype(mtype)
 107         do
 108                 if mtype isa MClassType and mtype.mclass.kind == extern_kind then return "void *"
 109                 return mtype.cname
 110         end
 111 end
 112
 113 # Context when calling generated code from user C code
 114 class FromCCallContext
 115         super CallContext
 116
 117         # TODO: private init because singleton instance (see `from_c_call_context`)
 118
 119         redef fun name_mtype(mtype) do return mtype.cname
 120 end
 121
 122 class ExternCFunction
 123         super CFunction
 124
 125         var method: AMethPropdef
 126
 127         init (method: AMethPropdef, mmodule: MModule)
 128         do
 129                 self.method = method
 130
 131                 var recv_mtype = method.mpropdef.mclassdef.bound_mtype
 132                 var csignature = method.mpropdef.mproperty.build_csignature(recv_mtype, mmodule, "___impl", long_signature, from_c_call_context)
 133
 134                 super( csignature )
 135         end
 136 end