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347 | ------------------------------------------------------------------------------
-- XML/Ada - An XML suite for Ada95 --
-- --
-- Copyright (C) 2001-2018, AdaCore --
-- --
-- This library is free software; you can redistribute it and/or modify it --
-- under terms of the GNU General Public License as published by the Free --
-- Software Foundation; either version 3, or (at your option) any later --
-- version. This library is distributed in the hope that it will be useful, --
-- but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHAN- --
-- TABILITY or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
------------------------------------------------------------------------------
with Unicode.CES; use Unicode.CES;
with Unicode.CES.Utf32; use Unicode.CES.Utf32;
with Unicode.CES.Utf16; use Unicode.CES.Utf16;
with Unicode.CES.Utf8; use Unicode.CES.Utf8;
with Ada.Characters.Handling; use Ada.Characters.Handling;
with GNAT.Regpat; use GNAT.Regpat;
with GNAT.Sockets; use GNAT.Sockets;
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Streams; use Ada.Streams;
package body Input_Sources.Http is
Debug : constant Boolean := False;
----------
-- Open --
----------
procedure Open
(Hostname : String;
Port : Positive := 80;
Filename : String;
Input : out Http_Input)
is
Length : Natural;
BOM : Bom_Type;
Socket : Socket_Type;
Addr : Sock_Addr_Type;
Channel : Stream_Access;
Image_Port : constant String := Positive'Image (Port);
HTTP_Token_OK : constant String := "HTTP/1\.\d \d\d\d (OK|FOUND)";
Content_Length_Token : constant String := "CONTENT-LENGTH: ";
-- These must be upper-cased.
Buffer : Stream_Element_Array (1 .. 2048);
Buffer_Last : Stream_Element_Count := 0;
Index : Stream_Element_Count := Buffer'First;
function Parse_Header return Natural;
-- Parse the headers of the http message, and return the length of the
-- message.
procedure Update_Buffer;
-- Read the next stream of bytes from the socket
function Get_Char return Character;
-- Return the next character from the buffer
procedure Send (Str : String);
-- Send a request to the server
--------------
-- Get_Char --
--------------
function Get_Char return Character is
begin
if Index >= Buffer_Last then
Update_Buffer;
end if;
if Index >= Buffer_Last then
return ASCII.NUL;
else
Index := Index + 1;
return Character'Val (Buffer (Index - 1));
end if;
end Get_Char;
-------------------
-- Update_Buffer --
-------------------
procedure Update_Buffer is
begin
GNAT.Sockets.Receive_Socket (Socket, Buffer, Buffer_Last);
if Debug then
Put ("< ");
for B in Buffer'First .. Buffer_Last loop
Put (Character'Val (Buffer (B)));
end loop;
New_Line;
end if;
Index := Buffer'First;
end Update_Buffer;
------------------
-- Parse_Header --
------------------
function Parse_Header return Natural is
Line : String (1 .. 2048);
Line_Index : Natural;
Length : Natural := 0;
C : Character;
Ok : Boolean := False;
Token : constant Pattern_Matcher := Compile (HTTP_Token_OK);
begin
loop
Line_Index := Line'First;
loop
C := Get_Char;
exit when C = ASCII.LF
or else C = ASCII.NUL;
Line (Line_Index) := To_Upper (C);
Line_Index := Line_Index + 1;
exit when Line_Index > Line'Last;
end loop;
if Line_Index > Line'First
and then Line (Line_Index - 1) = ASCII.CR
then
Line_Index := Line_Index - 1;
end if;
exit when Line_Index = Line'First;
if Match (Token, Line (Line'First .. Line_Index - 1)) then
Ok := True;
elsif Line_Index > Content_Length_Token'Length
and then Line (1 .. Content_Length_Token'Length) =
Content_Length_Token
then
begin
Length := Natural'Value
(Line (Content_Length_Token'Length + 1 .. Line_Index - 1));
exception
when others =>
Length := 0;
end;
end if;
end loop;
if Ok then
return Length;
else
return 0;
end if;
end Parse_Header;
----------
-- Send --
----------
procedure Send (Str : String) is
begin
if Debug then
Put_Line ("> " & Str);
end if;
String'Write (Channel, Str);
end Send;
begin
if Debug then
Put_Line ("Hostname: " & Hostname);
Put_Line ("Port: " & Integer'Image (Port));
Put_Line ("File: " & Filename);
end if;
Addr := (GNAT.Sockets.Family_Inet,
Addresses (Get_Host_By_Name (Hostname), 1),
Port_Type (Port));
Create_Socket (Socket);
Set_Socket_Option (Socket, Socket_Level, (Reuse_Address, True));
Set_Socket_Option (Socket, Socket_Level, (Receive_Buffer, 3000));
Connect_Socket (Socket, Addr);
Channel := Stream (Socket);
Send ("GET http://"
& Hostname & ":"
& Image_Port (Image_Port'First + 1 .. Image_Port'Last)
& "/" & Filename & " HTTP/1.0" & ASCII.LF);
Send ("" & ASCII.LF);
Length := Parse_Header;
if Length = 0 then
Put_Line ("Nothing to read");
raise Http_Error;
end if;
Input.Buffer := new String (1 .. Length - 1);
Input.Index := 1;
for A in 1 .. Length - 1 loop
Input.Buffer (A) := Get_Char;
end loop;
Read_Bom (Input.Buffer.all, Input.Prolog_Size, BOM);
case BOM is
when Utf32_LE =>
Set_Encoding (Input, Utf32_LE_Encoding);
when Utf32_BE =>
Set_Encoding (Input, Utf32_BE_Encoding);
when Utf16_LE =>
Set_Encoding (Input, Utf16_LE_Encoding);
when Utf16_BE =>
Set_Encoding (Input, Utf16_BE_Encoding);
when others =>
Set_Encoding (Input, Utf8_Encoding);
end case;
Input.Index := Input.Buffer'First + Input.Prolog_Size;
Close_Socket (Socket);
end Open;
----------
-- Open --
----------
procedure Open (URL : String; Input : out Http_Input) is
Host_Start, Host_End : Natural;
Port : Integer := 80;
File_Start : Integer;
begin
if URL'Length > 6
and then URL (URL'First .. URL'First + 6) = "http://"
then
Host_Start := URL'First + 7;
Host_End := Host_Start;
while Host_End <= URL'Last
and then URL (Host_End) /= '/'
and then URL (Host_End) /= ':'
loop
Host_End := Host_End + 1;
end loop;
if Host_End > URL'Last then
-- Invalid URL
Put_Line ("Invalid URL");
raise Http_Error;
end if;
if URL (Host_End) = ':' then
File_Start := Host_End + 1;
while File_Start <= URL'Last
and then URL (File_Start) /= '/'
loop
File_Start := File_Start + 1;
end loop;
if File_Start > URL'Last then
-- Invalid URL
Put_Line ("Invalid URL");
raise Http_Error;
end if;
begin
Port := Integer'Value (URL (Host_End + 1 .. File_Start - 1));
exception
when others =>
Port := 80;
end;
File_Start := File_Start + 1;
else
File_Start := Host_End + 1;
end if;
Open (Hostname => URL (Host_Start .. Host_End - 1),
Port => Port,
Filename => URL (File_Start .. URL'Last),
Input => Input);
else
-- Invalid URL
Put_Line ("Invalid URL");
raise Http_Error;
end if;
end Open;
-----------
-- Close --
-----------
procedure Close (Input : in out Http_Input) is
begin
Input_Sources.Close (Input_Source (Input));
Free (Input.Buffer);
Input.Index := Natural'Last;
end Close;
---------------
-- Next_Char --
---------------
procedure Next_Char
(From : in out Http_Input;
C : out Unicode.Unicode_Char) is
begin
From.Es.Read (From.Buffer.all, From.Index, C);
C := From.Cs.To_Unicode (C);
exception
-- The whole page has been fully loaded in the Open step.
-- Hence if the buffer ends with an Incomplete_Encoding, this
-- is a fatale error.
when Incomplete_Encoding =>
raise Invalid_Encoding;
end Next_Char;
---------
-- Eof --
---------
function Eof (From : Http_Input) return Boolean is
begin
return From.Buffer = null
or else From.Index > From.Buffer'Length;
end Eof;
begin
pragma Warnings (Off);
GNAT.Sockets.Initialize;
pragma Warnings (On);
end Input_Sources.Http;
|