gcc/ada/libgnat/g-sercom__mingw.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --           G N A T . S E R I A L _ C O M M U N I C A T I O N S            --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --                    Copyright (C) 2007-2020, AdaCore                      --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
  17 --                                                                          --
  18 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 3.1, as published by the Free Software Foundation.               --
  21 --                                                                          --
  22 -- You should have received a copy of the GNU General Public License and    --
  23 -- a copy of the GCC Runtime Library Exception along with this program;     --
  24 -- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
  25 -- <http://www.gnu.org/licenses/>.                                          --
  26 --                                                                          --
  27 -- GNAT was originally developed  by the GNAT team at  New York University. --
  28 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  29 --                                                                          --
  30 ------------------------------------------------------------------------------
  31
  32 --  This is the Windows implementation of this package
  33
  34 with Ada.Streams;          use Ada.Streams, Ada;
  35
  36 with System;               use System;
  37 with System.Communication; use System.Communication;
  38 with System.CRTL;          use System.CRTL;
  39 with System.Win32;         use System.Win32;
  40 with System.Win32.Ext;     use System.Win32.Ext;
  41
  42 with GNAT.OS_Lib;
  43
  44 package body GNAT.Serial_Communications is
  45
  46    package OSC renames System.OS_Constants;
  47
  48    --  Common types
  49
  50    C_Bits      : constant array (Data_Bits) of Interfaces.C.unsigned := (8, 7);
  51    C_Parity    : constant array (Parity_Check) of Interfaces.C.unsigned :=
  52                    (None => NOPARITY, Odd => ODDPARITY, Even => EVENPARITY);
  53    C_Stop_Bits : constant array (Stop_Bits_Number) of Interfaces.C.unsigned :=
  54                    (One => ONESTOPBIT, Two => TWOSTOPBITS);
  55
  56    -----------
  57    -- Files --
  58    -----------
  59
  60    procedure Raise_Error (Message : String; Error : DWORD := GetLastError);
  61    pragma No_Return (Raise_Error);
  62
  63    -----------
  64    -- Close --
  65    -----------
  66
  67    procedure Close (Port : in out Serial_Port) is
  68       Success : BOOL;
  69
  70    begin
  71       if Port.H /= -1 then
  72          Success := CloseHandle (HANDLE (Port.H));
  73
  74          if Success = Win32.FALSE then
  75             Raise_Error ("error closing the port");
  76          end if;
  77       end if;
  78    end Close;
  79
  80    ----------
  81    -- Name --
  82    ----------
  83
  84    function Name (Number : Positive) return Port_Name is
  85       N_Img : constant String := Positive'Image (Number);
  86    begin
  87       if Number > 9 then
  88          return
  89            Port_Name ("\\.\COM" & N_Img (N_Img'First + 1 .. N_Img'Last));
  90       else
  91          return
  92            Port_Name ("COM" & N_Img (N_Img'First + 1 .. N_Img'Last) & ':');
  93       end if;
  94    end Name;
  95
  96    ----------
  97    -- Open --
  98    ----------
  99
 100    procedure Open
 101      (Port : out Serial_Port;
 102       Name : Port_Name)
 103    is
 104       C_Name  : constant String := String (Name) & ASCII.NUL;
 105       Success : BOOL;
 106       pragma Unreferenced (Success);
 107
 108    begin
 109       if Port.H /= -1 then
 110          Success := CloseHandle (HANDLE (Port.H));
 111       end if;
 112
 113       Port.H := CreateFileA
 114         (lpFileName            => C_Name (C_Name'First)'Address,
 115          dwDesiredAccess       => GENERIC_READ or GENERIC_WRITE,
 116          dwShareMode           => 0,
 117          lpSecurityAttributes  => null,
 118          dwCreationDisposition => OPEN_EXISTING,
 119          dwFlagsAndAttributes  => 0,
 120          hTemplateFile         => 0);
 121
 122       pragma Assert (INVALID_HANDLE_VALUE = -1);
 123
 124       if Port.H = Serial_Port_Descriptor (INVALID_HANDLE_VALUE) then
 125          Raise_Error ("cannot open com port");
 126       end if;
 127    end Open;
 128
 129    -----------------
 130    -- Raise_Error --
 131    -----------------
 132
 133    procedure Raise_Error (Message : String; Error : DWORD := GetLastError) is
 134    begin
 135       raise Serial_Error with Message
 136         & (if Error /= 0
 137            then " (" & GNAT.OS_Lib.Errno_Message (Err => Integer (Error)) & ')'
 138            else "");
 139    end Raise_Error;
 140
 141    ----------
 142    -- Read --
 143    ----------
 144
 145    overriding procedure Read
 146      (Port   : in out Serial_Port;
 147       Buffer : out Stream_Element_Array;
 148       Last   : out Stream_Element_Offset)
 149    is
 150       Success   : BOOL;
 151       Read_Last : aliased DWORD;
 152
 153    begin
 154       if Port.H = -1 then
 155          Raise_Error ("read: port not opened", 0);
 156       end if;
 157
 158       Success :=
 159         ReadFile
 160           (hFile                => HANDLE (Port.H),
 161            lpBuffer             => Buffer (Buffer'First)'Address,
 162            nNumberOfBytesToRead => DWORD (Buffer'Length),
 163            lpNumberOfBytesRead  => Read_Last'Access,
 164            lpOverlapped         => null);
 165
 166       if Success = Win32.FALSE then
 167          Raise_Error ("read error");
 168       end if;
 169
 170       Last := Last_Index (Buffer'First, CRTL.size_t (Read_Last));
 171    end Read;
 172
 173    ---------
 174    -- Set --
 175    ---------
 176
 177    procedure Set
 178      (Port      : Serial_Port;
 179       Rate      : Data_Rate        := B9600;
 180       Bits      : Data_Bits        := CS8;
 181       Stop_Bits : Stop_Bits_Number := One;
 182       Parity    : Parity_Check     := None;
 183       Block     : Boolean          := True;
 184       Local     : Boolean          := True;
 185       Flow      : Flow_Control     := None;
 186       Timeout   : Duration         := 10.0)
 187    is
 188       pragma Unreferenced (Local);
 189
 190       Success      : BOOL;
 191       Com_Time_Out : aliased COMMTIMEOUTS;
 192       Com_Settings : aliased DCB;
 193
 194    begin
 195       if Port.H = -1 then
 196          Raise_Error ("set: port not opened", 0);
 197       end if;
 198
 199       Success := GetCommState (HANDLE (Port.H), Com_Settings'Access);
 200
 201       if Success = Win32.FALSE then
 202          Success := CloseHandle (HANDLE (Port.H));
 203          Raise_Error ("set: cannot get comm state");
 204       end if;
 205
 206       Com_Settings.BaudRate        := DWORD (Data_Rate_Value (Rate));
 207       Com_Settings.fParity         := 1;
 208       Com_Settings.fBinary         := Bits1 (System.Win32.TRUE);
 209       Com_Settings.fOutxDsrFlow    := 0;
 210       Com_Settings.fDsrSensitivity := 0;
 211       Com_Settings.fDtrControl     := OSC.DTR_CONTROL_ENABLE;
 212       Com_Settings.fInX            := 0;
 213       Com_Settings.fRtsControl     := OSC.RTS_CONTROL_ENABLE;
 214
 215       case Flow is
 216          when None =>
 217             Com_Settings.fOutX        := 0;
 218             Com_Settings.fOutxCtsFlow := 0;
 219
 220          when RTS_CTS =>
 221             Com_Settings.fOutX        := 0;
 222             Com_Settings.fOutxCtsFlow := 1;
 223
 224          when Xon_Xoff =>
 225             Com_Settings.fOutX        := 1;
 226             Com_Settings.fOutxCtsFlow := 0;
 227       end case;
 228
 229       Com_Settings.fAbortOnError := 0;
 230       Com_Settings.ByteSize      := BYTE (C_Bits (Bits));
 231       Com_Settings.Parity        := BYTE (C_Parity (Parity));
 232       Com_Settings.StopBits      := BYTE (C_Stop_Bits (Stop_Bits));
 233
 234       Success := SetCommState (HANDLE (Port.H), Com_Settings'Access);
 235
 236       if Success = Win32.FALSE then
 237          Success := CloseHandle (HANDLE (Port.H));
 238          Raise_Error ("cannot set comm state");
 239       end if;
 240
 241       --  Set the timeout status, to honor our spec with respect to read
 242       --  timeouts. Always disconnect write timeouts.
 243
 244       --  Blocking reads - no timeout at all
 245
 246       if Block then
 247          Com_Time_Out := (others => 0);
 248
 249       --  Non-blocking reads and null timeout - immediate return with what we
 250       --  have - set ReadIntervalTimeout to MAXDWORD.
 251
 252       elsif Timeout = 0.0 then
 253          Com_Time_Out :=
 254            (ReadIntervalTimeout => DWORD'Last,
 255             others              => 0);
 256
 257       --  Non-blocking reads with timeout - set total read timeout accordingly
 258
 259       else
 260          Com_Time_Out :=
 261            (ReadTotalTimeoutConstant => DWORD (1000 * Timeout),
 262             others                   => 0);
 263       end if;
 264
 265       Success :=
 266         SetCommTimeouts
 267           (hFile          => HANDLE (Port.H),
 268            lpCommTimeouts => Com_Time_Out'Access);
 269
 270       if Success = Win32.FALSE then
 271          Raise_Error ("cannot set the timeout");
 272       end if;
 273    end Set;
 274
 275    ------------
 276    -- To_Ada --
 277    ------------
 278
 279    procedure To_Ada (Port : out Serial_Port; Fd : Serial_Port_Descriptor) is
 280    begin
 281       Port.H := Fd;
 282    end To_Ada;
 283
 284    -----------
 285    -- Write --
 286    -----------
 287
 288    overriding procedure Write
 289      (Port   : in out Serial_Port;
 290       Buffer : Stream_Element_Array)
 291    is
 292       Success   : BOOL;
 293       Temp_Last : aliased DWORD;
 294
 295    begin
 296       if Port.H = -1 then
 297          Raise_Error ("write: port not opened", 0);
 298       end if;
 299
 300       Success :=
 301         WriteFile
 302           (hFile                  => HANDLE (Port.H),
 303            lpBuffer               => Buffer'Address,
 304            nNumberOfBytesToWrite  => DWORD (Buffer'Length),
 305            lpNumberOfBytesWritten => Temp_Last'Access,
 306            lpOverlapped           => null);
 307
 308       if Success = Win32.FALSE
 309         or else Stream_Element_Offset (Temp_Last) /= Buffer'Length
 310       then
 311          Raise_Error ("failed to write data");
 312       end if;
 313    end Write;
 314
 315 end GNAT.Serial_Communications;