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Diffstat (limited to 'gcc-4.3.1/gcc/ada/s-wchcnv.ads')
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diff --git a/gcc-4.3.1/gcc/ada/s-wchcnv.ads b/gcc-4.3.1/gcc/ada/s-wchcnv.ads new file mode 100644 index 000000000..3679b881a --- /dev/null +++ b/gcc-4.3.1/gcc/ada/s-wchcnv.ads @@ -0,0 +1,120 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- S Y S T E M . W C H _ C N V -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2007, Free Software Foundation, Inc. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 2, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This package contains generic subprograms used for converting between +-- sequences of Character and Wide_Character. Wide_Wide_Character values +-- are also handled, but represented using integer range types defined in +-- this package, so that this package can be used from applications that +-- are restricted to Ada 95 compatibility (such as the compiler itself). + +-- All the algorithms for encoding and decoding are isolated in this package +-- and in System.WCh_JIS and should not be duplicated elsewhere. The only +-- exception to this is that GNAT.Decode_String and GNAT.Encode_String have +-- their own circuits for UTF-8 conversions, for improved efficiency. + +-- This unit may be used directly from an application program by providing +-- an appropriate WITH, and the interface can be expected to remain stable. + +pragma Warnings (Off); +pragma Compiler_Unit; +pragma Warnings (On); + +with System.WCh_Con; + +package System.WCh_Cnv is + pragma Pure; + + type UTF_32_Code is range 0 .. 16#7FFF_FFFF#; + for UTF_32_Code'Size use 32; + -- Range of allowed UTF-32 encoding values + + type UTF_32_String is array (Positive range <>) of UTF_32_Code; + + generic + with function In_Char return Character; + function Char_Sequence_To_Wide_Char + (C : Character; + EM : System.WCh_Con.WC_Encoding_Method) return Wide_Character; + -- C is the first character of a sequence of one or more characters which + -- represent a wide character sequence. Calling the function In_Char for + -- additional characters as required, Char_To_Wide_Char returns the + -- corresponding wide character value. Constraint_Error is raised if the + -- sequence of characters encountered is not a valid wide character + -- sequence for the given encoding method. + -- + -- Note on the use of brackets encoding (WCEM_Brackets). The brackets + -- encoding method is ambiguous in the context of this function, since + -- there is no way to tell if ["1234"] is eight unencoded characters or + -- one encoded character. In the context of Ada sources, any sequence + -- starting [" must be the start of an encoding (since that sequence is + -- not valid in Ada source otherwise). The routines in this package use + -- the same approach. If the input string contains the sequence [" then + -- this is assumed to be the start of a brackets encoding sequence, and + -- if it does not match the syntax, an error is raised. + + generic + with function In_Char return Character; + function Char_Sequence_To_UTF_32 + (C : Character; + EM : System.WCh_Con.WC_Encoding_Method) return UTF_32_Code; + -- This is similar to the above, but the function returns a code from + -- the full UTF_32 code set, which covers the full range of possible + -- values in Wide_Wide_Character. The result can be converted to + -- Wide_Wide_Character form using Wide_Wide_Character'Val. + + generic + with procedure Out_Char (C : Character); + procedure Wide_Char_To_Char_Sequence + (WC : Wide_Character; + EM : System.WCh_Con.WC_Encoding_Method); + -- Given a wide character, converts it into a sequence of one or + -- more characters, calling the given Out_Char procedure for each. + -- Constraint_Error is raised if the given wide character value is + -- not a valid value for the given encoding method. + -- + -- Note on brackets encoding (WCEM_Brackets). For the input routines above, + -- upper half characters can be represented as ["hh"] but this procedure + -- will only use brackets encodings for codes higher than 16#FF#, so upper + -- half characters will be output as single Character values. + + generic + with procedure Out_Char (C : Character); + procedure UTF_32_To_Char_Sequence + (Val : UTF_32_Code; + EM : System.WCh_Con.WC_Encoding_Method); + -- This is similar to the above, but the input value is a code from the + -- full UTF_32 code set, which covers the full range of possible values + -- in Wide_Wide_Character. To convert a Wide_Wide_Character value, the + -- caller can use Wide_Wide_Character'Pos in the call. + +end System.WCh_Cnv; |