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SynCrtSock.pas
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/// classes implementing HTTP/1.1 client and server protocol
// - this unit is a part of the freeware Synopse mORMot framework,
// licensed under a MPL/GPL/LGPL tri-license; version 1.18
unit SynCrtSock;
{
This file is part of Synopse framework.
Synopse framework. Copyright (C) 2019 Arnaud Bouchez
Synopse Informatique - https://synopse.info
*** BEGIN LICENSE BLOCK *****
Version: MPL 1.1/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Mozilla Public License Version
1.1 (the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL
Software distributed under the License is distributed on an "AS IS" basis,
WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
for the specific language governing rights and limitations under the License.
The Original Code is Synopse mORMot framework.
The Initial Developer of the Original Code is Arnaud Bouchez.
Portions created by the Initial Developer are Copyright (C) 2019
the Initial Developer. All Rights Reserved.
Contributor(s):
- Alfred Glaenzer (alf)
- Cybexr
- EMartin
- Eric Grange
- Eugene Ilyin
- EvaF
- f-vicente
- Maciej Izak (hnb)
- Marius Maximus
- Mr Yang (ysair)
- Pavel Mashlyakovskii (mpv)
- Willo vd Merwe
Alternatively, the contents of this file may be used under the terms of
either the GNU General Public License Version 2 or later (the "GPL"), or
the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the MPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the MPL, the GPL or the LGPL.
***** END LICENSE BLOCK *****
TCP/IP and HTTP/1.1 Client and Server
***************************************
Initial version: 2009 May, by Arnaud Bouchez
Version 1.4 - February 8, 2010
- whole Synopse SQLite3 database framework released under the GNU Lesser
General Public License version 3, instead of generic "Public Domain"
- fix a bug happening when multiple HTTP connections were opened and
closed in the same program
Version 1.5 - March 1, 2010
- new generic unix implementation, using libc sockets, in SynLibcSock.pas
Version 1.9
- avoid some GPF during client deconnection when the server shut down
- rewrite HTTP Server handle request loop keep alive timing
- HTTP Server now use a Thread Pool to speed up multi-connections: this
speed up a lot HTTP/1.0 requests, by creating a Thread only if
necessary
Version 1.9.2
- deleted deprecated DOS related code (formerly used with DWPL Dos Extender)
- a dedicated thread is now used if the incoming HTTP request has
POSTed a body content of more than 16 KB (to avoid Deny Of Service, and
preserve the Thread Pool to only real small processes)
- new CROnly parameter for TCrtSocket.SockRecvLn, to handle #13 as
line delimiter: by default, #10 or #13#10 are line delimiters
(as for normal Window/Linux text files)
Version 1.12
- added connection check and exception handling in
THttpServerSocket.GetRequest, which now is a function returning a boolean
- added DOS / TCP SYN Flood detection if THttpServerSocket.GetRequest
spent more than 2 seconds to get header from HTTP Client
Version 1.13
- code modifications to compile with Delphi 5 compiler
- new THttpApiServer class, using fast http.sys kernel-mode server
for better performance and less resource usage
- DOS / TCP SYN Flood detection time enhanced to 5 seconds
- fixed HTTP client stream layout (to be more RFC compliant)
- new generic compression handling mechanism: can handle gzip, deflate
or custom synlz / synlzo algorithms via THttpSocketCompress functions
- new THttpServerGeneric.Request virtual abstract method prototype
- new TWinINet class, using WinINet API (very slow, do not use)
- new TWinHTTP class, using WinHTTP API (faster than THttpClientSocket):
this is the class to be used
Version 1.15
- unit now tested with Delphi XE2 (32 Bit)
- fixed issue in HTTP_RESPONSE.SetHeaders()
Version 1.16
- fixed issue in case of wrong void parameter e.g. in THttpApiServer.AddUrl
- circumvent some bugs of Delphi XE2 background compiler (main compiler is OK)
- added 'RemoteIP: 127.0.0.1' to the retrieved HTTP headers
- major speed up of THttpApiServer for Windows Vista and up, by processing
huge content in chunks: upload of 100Mb file take 25 sec before and 6 sec
after changes, according to feedback by MPV - ticket 711247b998
- new THttpServerGeneric.OnHttpThreadTerminate event, available to clean-up
any process in the thread context, when it is terminated (to call e.g.
TSQLDBConnectionPropertiesThreadSafe.EndCurrentThread in order to call
CoUnInitialize from thread in which CoInitialize was initialy made) - see
https://synopse.info/fossil/tktview?name=213544b2f5
Version 1.17
- replaced TSockData string type to the generic RawByteString type (and
the default AnsiString for non-Unicode version of Delphi)
- added optional aProxyName, aProxyByPass parameters to TWinHttpAPI /
TWinInet and TWinHTTP constructors
- added THttpServerGeneric.OnHttpThreadStart property, and associated
TNotifyThreadEvent event prototype
- handle 'Range: bytes=***-***' request in THttpApiServer
Version 1.18
- replaced RawByteString type (defined locally for non-Unicode version of
Delphi) by a dedicated SockString type, used for data storage and for
simple ASCII content (like URIs or port number)
- added and tested Linux support (FPC/CrossKylix), via sockets or libcurl API
- introducing THttpServerRequest class for HTTP server context and THttpRequest
(replacing TWinHttpAPI) as abstract parent for HTTP client classes
- http.sys kernel-mode server now handles HTTP API 2.0 (available since
Windows Vista / Server 2008), or fall back to HTTP API 1.0 (for Windows XP
or Server 2003) - thanks pavel for the feedback and initial patch!
- deep code refactoring of thread process, especially for TSynThreadPool as
used by THttpServer: introducing TSynThread and TSynThreadPoolSubThread;
as a result, it fixes OnHttpThreadStart and OnHttpThreadTerminate to be
triggered from every thread, and propagated from THttpApiServer's clones
- added TCrtSocket.TCPNoDelay/SendTimeout/ReceiveTimeout/KeepAlive properties
- added optional parameter to set buffer size for TCrtSocket.CreateSockIn
and TCrtSocket.CreateSockOut methods
- renamed misleading TCrtSocket.Snd method as overloaded SockSend, and
refactored public fields as read/only properties
- fixed long-standing random bug occuring when a TCrtSocket connection is
closed then reopened (e.g. when THttpClientSocket.Request does its retrial);
thanks hnb for the patch!
- added THttpServerRequest.UseSSL property to check if connection is secured
- added optional queue name for THttpApiServer.Create constructor [149cf42383]
- added THttpApiServer.RemoveUrl() method
- introduced THttpApiServer.ReceiveBufferSize property
- added HTTPQueueLength property (for HTTP API 2.0 only)
- added THttpApiServer.MaxBandwidth and THttpApiServer.MaxConnections
properties (for HTTP API 2.0 only) - thanks mpv for the proposal!
- added THttpApiServer.LogStart/LogStop for HTTP API 2.0 integrated logging
- introducing new THttpApiServer.SetAuthenticationSchemes() method for HTTP
API 2.0, and the corresponding THttpServerRequest.AuthenticationStatus and
AuthenticatedUser properties
- added THttpApiServer.SetTimeOutLimits() method for HTTP API 2.0
- added THttpApiServer.ServerSessionID and UrlGroupID read-only properties
- let HTTP_RESPONSE.AddCustomHeader() recognize all known headers
- THttpApiServer won't try to send an error message when connection is broken
- added error check for HttpSendHttpResponse() API call
- added EWinHTTP exception, raised when TWinHttp client fails to connect
- added aTimeOut optional parameter to TCrtSocket.Open() constructor
- added function HtmlEncode()
- some code cleaning about 64-bit compilation (including [540628f498])
- refactored HTTP_DATA_CHUNK record definition into HTTP_DATA_CHUNK_* records
to circumvent XE3 alignemnt issue
- WinSock-based THttpServer will avoid creating a thread per connection,
when the maximum of 256 threads is reached in the pool, with an exception
of kept-alife or huge body requets (avoiding DoS attacks by limiting the
total number of created threads)
- allow WinSock-based THttpServer to set a server address ('1.2.3.4:1234')
- let WinSock-based THttpServer.Process() handle HTTP_RESP_STATICFILE
- force disable range checking and other compiler options for this unit
- included more detailed information to HTTP client User-Agent header
- added ConnectionTimeOut, SendTimeout and ReceiveTimeout optional parameters
to THttpRequest constructors - feature request [bfe485b678]
- added optional aCompressMinSize parameter to RegisterCompress() methods
- added THttpRequest.Get/Post/Put/Delete() class functions for easy remote
resource retrieval using either WinHTTP or WinINet APIs
- added TURI structure, ready to parse a supplied HTTP URI
- added ConnectionID the HTTP server context - see request [0636eeec54]
- added THttpRequest.IgnoreSSLCertificateErrors property (proposal by EMartin)
- added THttpRequest AuthScheme and AuthUserName/AuthPassword properties, for
authentication - only implemented at TWinHttp level (thanks Eric Grange)
- fixed TCrtSocket.BytesIn and TCrtSocket.BytesOut properties
- fixed ticket [82df275784] THttpRequest with responses without Content-Length
- fixed ticket [f0749956af] TWinINet does not work with HTTPS servers
- fixed ticket [842a5ae15a] THttpApiServer.Execute/SendError message
- fixed ticket [f2ae4022a4] EWinINet error handling
- fixed ticket [73da2c17b1] about Accept-Encoding header in THttpApiServer
- fixed ticket [cbcbb3b2fc] about PtrInt definition
- fixed ticket [91f8f3ec6f] about error retrieving unknown headers
- fixed ticket [f79ff5714b] about potential finalization issues as .bpl in IDE
- fixed ticket [2d53fc43e3] about unneeded port 80
- fixed ticket [11b327bd77] about TCrtSocket not working with Delphi 2009+
- fixed ticket [0f6ecdaf55] for better compatibility with HTTP/1.1 cache
- fixed ticket [814f6bd65a] about missing OnHttpThreadStart in CreateClone
- fixed ticket [51a9c086f3] about THttpApiServer.SetHTTPQueueLength()
- fixed potential Access Violation error at THttpServerResp shutdown
- removed several compilation hints when assertions are set to off
- added aRegisterURI optional parameter to THttpApiServer.AddUrl() method
- made exception error messages more explicit (tuned per module)
- fixed several issues when releasing THttpApiServer and THttpServer instances
- allow to use any Unicode content for SendEmail() - also includes
SendEmailSubject() function, for feature request [0a5fdf9129]
- added support for TLS1.1 & TLS1.2 for TWinHTTP
- added advanced exception text if case of HTTPS connection problems
- added HTTP.SYS 2.0 web socket API TWebSocketAPI
- added HTTP.SYS 2.0 based WebSocket server THttpApiWebSocketServer
- added direct SChannel API TLS support on Windows
}
{$I Synopse.inc} // define HASINLINE ONLYUSEHTTPSOCKET USELIBCURL SYNCRTDEBUGLOW
{.$define SYNCRTDEBUGLOW}
// internal use: enable some low-level log messages for HTTP socket debugging
interface
uses
SysUtils, // put first to use SynFPCLinux/SynKylix GetTickCount64
{$ifndef LVCL}
Contnrs,
SyncObjs, // for TEvent (in Classes.pas for LVCL)
{$endif LVCL}
{$ifdef SYNCRTDEBUGLOW}
SynCommons,
SynLog,
{$endif SYNCRTDEBUGLOW}
{$ifdef USELIBCURL}
SynCurl,
{$endif USELIBCURL}
{$ifdef FPC}
dynlibs,
{$endif FPC}
{$ifdef MSWINDOWS}
Windows,
SynWinSock,
{$ifdef USEWININET}
WinInet,
{$endif USEWININET}
{$ifndef DELPHI5OROLDER}
Types,
{$endif DELPHI5OROLDER}
{$else MSWINDOWS}
{$undef USEWININET}
{$ifdef FPC}
SynFPCSock,
SynFPCLinux,
BaseUnix, // for fpgetrlimit/fpsetrlimit
{$ifdef LINUXNOTBSD}
Linux,
{$endif LINUXNOTBSD}
{$else}
{$ifndef DELPHI5OROLDER}
Types,
{$endif DELPHI5OROLDER}
{$endif FPC}
{$ifdef KYLIX3}
KernelIoctl, // for IoctlSocket/ioctl FION* constants
LibC,
SynFPCSock, // shared with Kylix
SynKylix,
{$endif KYLIX3}
{$endif MSWINDOWS}
Classes;
const
/// the full text of the current Synopse mORMot framework version
// - match the value defined in SynCommons.pas and SynopseCommit.inc
// - we don't supply full version number with build revision, to reduce
// potential attack surface
XPOWEREDPROGRAM = 'mORMot 1.18';
/// the running Operating System
XPOWEREDOS = {$ifdef MSWINDOWS} 'Windows' {$else}
{$ifdef LINUXNOTBSD} 'Linux' {$else} 'Posix' {$endif LINUXNOTBSD}
{$endif MSWINDOWS};
/// used by THttpApiServer.Request for http.sys to send a static file
// - the OutCustomHeader should contain the proper 'Content-type: ....'
// corresponding to the file (e.g. by calling GetMimeContentType() function
// from SynCommons supplyings the file name)
// - should match HTML_CONTENT_STATICFILE constant defined in mORMot.pas unit
HTTP_RESP_STATICFILE = '!STATICFILE';
/// used to notify e.g. the THttpServerRequest not to wait for any response
// from the client
// - is not to be used in normal HTTP process, but may be used e.g. by
// TWebSocketProtocolRest.ProcessFrame() to avoid to wait for an incoming
// response from the other endpoint
// - should match NORESPONSE_CONTENT_TYPE constant defined in mORMot.pas unit
HTTP_RESP_NORESPONSE = '!NORESPONSE';
var
/// THttpRequest timeout default value for DNS resolution
// - leaving to 0 will let system default value be used
HTTP_DEFAULT_RESOLVETIMEOUT: integer = 0;
/// THttpRequest timeout default value for remote connection
// - default is 60 seconds
// - used e.g. by THttpRequest, TSQLHttpClientRequest and TSQLHttpClientGeneric
HTTP_DEFAULT_CONNECTTIMEOUT: integer = 60000;
/// THttpRequest timeout default value for data sending
// - default is 30 seconds
// - used e.g. by THttpRequest, TSQLHttpClientRequest and TSQLHttpClientGeneric
// - you can override this value by setting the corresponding parameter in
// THttpRequest.Create() constructor
HTTP_DEFAULT_SENDTIMEOUT: integer = 30000;
/// THttpRequest timeout default value for data receiving
// - default is 30 seconds
// - used e.g. by THttpRequest, TSQLHttpClientRequest and TSQLHttpClientGeneric
// - you can override this value by setting the corresponding parameter in
// THttpRequest.Create() constructor
HTTP_DEFAULT_RECEIVETIMEOUT: integer = 30000;
type
{$ifdef UNICODE}
/// define the fastest Unicode string type of the compiler
SynUnicode = UnicodeString;
/// define a raw 8-bit storage string type, used for data buffer management
SockString = type RawByteString;
{$else}
/// define the fastest 16-bit Unicode string type of the compiler
SynUnicode = WideString;
{$ifdef HASCODEPAGE} // FPC may expect a CP, e.g. to compare two string constants
SockString = type RawByteString;
{$else}
/// define a 8-bit raw storage string type, used for data buffer management
SockString = type AnsiString;
{$endif}
{$endif}
/// points to a 8-bit raw storage variable, used for data buffer management
PSockString = ^SockString;
/// defines a dynamic array of SockString
TSockStringDynArray = array of SockString;
{$ifdef DELPHI5OROLDER}
// not defined in Delphi 5 or older
PPointer = ^Pointer;
TTextLineBreakStyle = (tlbsLF, tlbsCRLF);
UTF8String = AnsiString;
UTF8Encode = AnsiString;
{$endif}
{$ifndef FPC}
/// FPC 64-bit compatibility integer type
{$ifdef CPU64}
PtrInt = NativeInt;
PtrUInt = NativeUInt;
{$else}
PtrInt = integer;
PtrUInt = cardinal;
{$endif}
PPtrInt = ^PtrInt;
PPtrUInt = ^PtrUInt;
{$endif FPC}
{$M+}
/// exception thrown by the classes of this unit
ECrtSocket = class(Exception)
protected
fLastError: integer;
public
/// will concat the message with the WSAGetLastError information
constructor Create(const Msg: string); overload;
/// will concat the message with the supplied WSAGetLastError information
constructor Create(const Msg: string; Error: integer); overload;
/// will concat the message with the supplied WSAGetLastError information
constructor CreateFmt(const Msg: string; const Args: array of const; Error: integer); overload;
published
/// the associated WSAGetLastError value
property LastError: integer read fLastError;
end;
{$M-}
TCrtSocketClass = class of TCrtSocket;
/// the available available network transport layer
// - either TCP/IP, UDP/IP or Unix sockets
TCrtSocketLayer = (cslTCP, cslUDP, cslUNIX);
/// identify the incoming data availability in TCrtSocket.SockReceivePending
TCrtSocketPending = (cspSocketError, cspNoData, cspDataAvailable);
PTextFile = ^TextFile;
{$M+}
/// Fast low-level Socket implementation
// - direct access to the OS (Windows, Linux) network layer API
// - use Open constructor to create a client to be connected to a server
// - use Bind constructor to initialize a server
// - use SockIn and SockOut (after CreateSock*) to read/readln or write/writeln
// as with standard Delphi text files (see SendEmail implementation)
// - even if you do not use read(SockIn^), you may call CreateSockIn then
// read the (binary) content via SockInRead/SockInPending methods, which would
// benefit of the SockIn^ input buffer to maximize reading speed
// - to write data, CreateSockOut and write(SockOut^) is not mandatory: you
// rather may use SockSend() overloaded methods, followed by a SockFlush call
// - in fact, you can decide whatever to use none, one or both SockIn/SockOut
// - since this class rely on its internal optimized buffering system,
// TCP_NODELAY is set to disable the Nagle algorithm
// - our classes are (much) faster than the Indy or Synapse implementation
TCrtSocket = class
protected
fSock: TSocket;
fServer: SockString;
fPort: SockString;
fSockIn: PTextFile;
fSockOut: PTextFile;
fTimeOut: PtrInt;
fBytesIn: Int64;
fBytesOut: Int64;
fSocketLayer: TCrtSocketLayer;
fSockInEof, fTLS: boolean;
// updated by every SockSend() call
fSndBuf: SockString;
fSndBufLen: integer;
// updated during UDP connection, accessed via PeerAddress/PeerPort
fPeerAddr: TSockAddr;
{$ifdef MSWINDOWS}
fSecure: TSChannelClient;
{$endif MSWINDOWS}
procedure SetInt32OptionByIndex(OptName, OptVal: integer); virtual;
procedure AcceptRequest(aClientSock: TSocket; aRemoteIP: PSockString);
public
/// common initialization of all constructors
// - do not call directly, but use Open / Bind constructors instead
constructor Create(aTimeOut: PtrInt=10000); reintroduce; virtual;
/// connect to aServer:aPort
// - you may ask for a TLS secured client connection (only available under
// Windows by now, using the SChannel API - and not fully tested)
constructor Open(const aServer, aPort: SockString; aLayer: TCrtSocketLayer=cslTCP;
aTimeOut: cardinal=10000; aTLS: boolean=false);
/// bind to a Port
// - expects the port to be specified as Ansi string, e.g. '1234'
// - you can optionally specify a server address to bind to, e.g.
// '1.2.3.4:1234'
// - for unix domain socket use unix:/path/to/file
constructor Bind(const aPort: SockString; aLayer: TCrtSocketLayer=cslTCP);
/// low-level internal method called by Open() and Bind() constructors
// - raise an ECrtSocket exception on error
// - you may ask for a TLS secured client connection (only available under
// Windows by now, using the SChannel API - and not fully tested)
procedure OpenBind(const aServer, aPort: SockString; doBind: boolean;
aSock: integer=-1; aLayer: TCrtSocketLayer=cslTCP; aTLS: boolean=false);
/// initialize SockIn for receiving with read[ln](SockIn^,...)
// - data is buffered, filled as the data is available
// - read(char) or readln() is indeed very fast
// - multithread applications would also use this SockIn pseudo-text file
// - by default, expect CR+LF as line feed (i.e. the HTTP way)
procedure CreateSockIn(LineBreak: TTextLineBreakStyle=tlbsCRLF;
InputBufferSize: Integer=1024);
/// initialize SockOut for sending with write[ln](SockOut^,....)
// - data is sent (flushed) after each writeln() - it's a compiler feature
// - use rather SockSend() + SockSendFlush to send headers at once e.g.
// since writeln(SockOut^,..) flush buffer each time
procedure CreateSockOut(OutputBufferSize: Integer=1024);
/// finalize SockIn receiving buffer
// - you may call this method when you are sure that you don't need the
// input buffering feature on this connection any more (e.g. after having
// parsed the HTTP header, then rely on direct socket comunication)
procedure CloseSockIn;
/// finalize SockOut receiving buffer
// - you may call this method when you are sure that you don't need the
// output buffering feature on this connection any more (e.g. after having
// parsed the HTTP header, then rely on direct socket comunication)
procedure CloseSockOut;
/// close and shutdown the connection (called from Destroy)
procedure Close;
/// close the opened socket, and corresponding SockIn/SockOut
destructor Destroy; override;
/// read Length bytes from SockIn buffer + Sock if necessary
// - if SockIn is available, it first gets data from SockIn^.Buffer,
// then directly receive data from socket if UseOnlySockIn=false
// - if UseOnlySockIn=true, it will return the data available in SockIn^,
// and returns the number of bytes
// - can be used also without SockIn: it will call directly SockRecv()
// in such case (assuming UseOnlySockin=false)
function SockInRead(Content: PAnsiChar; Length: integer;
UseOnlySockIn: boolean=false): integer;
/// returns the number of bytes in SockIn buffer or pending in Sock
// - if SockIn is available, it first check from any data in SockIn^.Buffer,
// then call InputSock to try to receive any pending data if the buffer is
// void - unless aSocketForceCheck is TRUE, and both the buffer and the
// socket are asked for pending bytes (slower, but sometimes needed, e.g.
// if you are currently waiting for a whole header block to be available)
// - will wait up to the specified aTimeOutMS value (in milliseconds) for
// incoming data
// - returns -1 in case of a socket error (e.g. broken connection); you
// can raise a ECrtSocket exception to propagate the error
function SockInPending(aTimeOutMS: integer; aSocketForceCheck: boolean=false): integer;
/// check the connection status of the socket
function SockConnected: boolean;
/// simulate writeln() with direct use of Send(Sock, ..) - includes trailing #13#10
// - useful on multi-treaded environnement (as in THttpServer.Process)
// - no temp buffer is used
// - handle SockString, ShortString, Char, Integer parameters
// - raise ECrtSocket exception on socket error
procedure SockSend(const Values: array of const); overload;
/// simulate writeln() with a single line - includes trailing #13#10
procedure SockSend(const Line: SockString=''); overload;
/// append P^ data into SndBuf (used by SockSend(), e.g.) - no trailing #13#10
// - call SockSendFlush to send it through the network via SndLow()
procedure SockSend(P: pointer; Len: integer); overload;
/// flush all pending data to be sent, optionally with some body content
// - raise ECrtSocket on error
procedure SockSendFlush(const aBody: SockString='');
/// flush all pending data to be sent
// - returning true on success
function TrySockSendFlush: boolean;
/// how many bytes could be added by SockSend() in the internal buffer
function SockSendRemainingSize: integer;
/// fill the Buffer with Length bytes
// - use TimeOut milliseconds wait for incoming data
// - bypass the SockIn^ buffers
// - raise ECrtSocket exception on socket error
procedure SockRecv(Buffer: pointer; Length: integer);
/// check if there are some pending bytes in the input sockets API buffer
function SockReceivePending(TimeOutMS: integer): TCrtSocketPending;
/// returns the socket input stream as a string
function SockReceiveString: SockString;
/// fill the Buffer with Length bytes
// - use TimeOut milliseconds wait for incoming data
// - bypass the SockIn^ buffers
// - return false on any fatal socket error, true on success
// - call Close if the socket is identified as shutdown from the other side
// - you may optionally set StopBeforeLength=true, then the read bytes count
// are set in Length, even if not all expected data has been received - in
// this case, Close method won't be called
function TrySockRecv(Buffer: pointer; var Length: integer; StopBeforeLength: boolean=false): boolean;
/// call readln(SockIn^,Line) or simulate it with direct use of Recv(Sock, ..)
// - char are read one by one
// - use TimeOut milliseconds wait for incoming data
// - raise ECrtSocket exception on socket error
// - by default, will handle #10 or #13#10 as line delimiter (as normal text
// files), but you can delimit lines using #13 if CROnly is TRUE
procedure SockRecvLn(out Line: SockString; CROnly: boolean=false); overload;
/// call readln(SockIn^) or simulate it with direct use of Recv(Sock, ..)
// - char are read one by one
// - use TimeOut milliseconds wait for incoming data
// - raise ECrtSocket exception on socket error
// - line content is ignored
procedure SockRecvLn; overload;
/// direct send data through network
// - raise a ECrtSocket exception on any error
// - bypass the SockSend() or SockOut^ buffers
procedure SndLow(P: pointer; Len: integer);
/// direct send data through network
// - return false on any error, true on success
// - bypass the SndBuf or SockOut^ buffers
function TrySndLow(P: pointer; Len: integer): boolean;
/// returns the low-level error number
// - i.e. returns WSAGetLastError
function LastLowSocketError: Integer;
/// direct send data through network
// - raise a ECrtSocket exception on any error
// - bypass the SndBuf or SockOut^ buffers
// - raw Data is sent directly to OS: no LF/CRLF is appened to the block
procedure Write(const Data: SockString);
/// direct accept an new incoming connection on a bound socket
// - instance should have been setup as a server via a previous Bind() call
// - returns nil on error or a ResultClass instance on success
// - if ResultClass is nil, will return a plain TCrtSocket, but you may
// specify e.g. THttpServerSocket if you expect incoming HTTP requests
function AcceptIncoming(RemoteIP: PSockString=nil;
ResultClass: TCrtSocketClass=nil): TCrtSocket;
/// remote IP address of the last packet received (SocketLayer=slUDP only)
function PeerAddress: SockString;
/// remote IP port of the last packet received (SocketLayer=slUDP only)
function PeerPort: integer;
/// set the TCP_NODELAY option for the connection
// - default 1 (true) will disable the Nagle buffering algorithm; it should
// only be set for applications that send frequent small bursts of information
// without getting an immediate response, where timely delivery of data
// is required - so it expects buffering before calling Write() or SndLow()
// - you can set 0 (false) here to enable the Nagle algorithm, if needed
// - see http://www.unixguide.net/network/socketfaq/2.16.shtml
property TCPNoDelay: Integer index TCP_NODELAY write SetInt32OptionByIndex;
/// set the SO_SNDTIMEO option for the connection
// - i.e. the timeout, in milliseconds, for blocking send calls
// - see http://msdn.microsoft.com/en-us/library/windows/desktop/ms740476
property SendTimeout: Integer index SO_SNDTIMEO write SetInt32OptionByIndex;
/// set the SO_RCVTIMEO option for the connection
// - i.e. the timeout, in milliseconds, for blocking receive calls
// - see http://msdn.microsoft.com/en-us/library/windows/desktop/ms740476
property ReceiveTimeout: Integer index SO_RCVTIMEO write SetInt32OptionByIndex;
/// set the SO_KEEPALIVE option for the connection
// - 1 (true) will enable keep-alive packets for the connection
// - see http://msdn.microsoft.com/en-us/library/windows/desktop/ee470551
property KeepAlive: Integer index SO_KEEPALIVE write SetInt32OptionByIndex;
/// set the SO_LINGER option for the connection, to control its shutdown
// - by default (or Linger<0), Close will return immediately to the caller,
// and any pending data will be delivered if possible
// - Linger > 0 represents the time in seconds for the timeout period
// to be applied at Close; under Linux, will also set SO_REUSEADDR; under
// Darwin, set SO_NOSIGPIPE
// - Linger = 0 causes the connection to be aborted and any pending data
// is immediately discarded at Close
property Linger: Integer index SO_LINGER write SetInt32OptionByIndex;
/// after CreateSockIn, use Readln(SockIn^,s) to read a line from the opened socket
property SockIn: PTextFile read fSockIn;
/// after CreateSockOut, use Writeln(SockOut^,s) to send a line to the opened socket
property SockOut: PTextFile read fSockOut;
published
/// low-level socket handle, initialized after Open() with socket
property Sock: TSocket read fSock write fSock;
/// low-level socket type, initialized after Open() with socket
property SocketLayer: TCrtSocketLayer read fSocketLayer;
/// IP address, initialized after Open() with Server name
property Server: SockString read fServer;
/// IP port, initialized after Open() with port number
property Port: SockString read fPort;
/// if higher than 0, read loop will wait for incoming data till
// TimeOut milliseconds (default value is 10000) - used also in SockSend()
property TimeOut: PtrInt read fTimeOut;
/// total bytes received
property BytesIn: Int64 read fBytesIn;
/// total bytes sent
property BytesOut: Int64 read fBytesOut;
end;
{$M-}
/// event used to compress or uncompress some data during HTTP protocol
// - should always return the protocol name for ACCEPT-ENCODING: header
// e.g. 'gzip' or 'deflate' for standard HTTP format, but you can add
// your own (like 'synlzo' or 'synlz')
// - the data is compressed (if Compress=TRUE) or uncompressed (if
// Compress=FALSE) in the Data variable (i.e. it is modified in-place)
// - to be used with THttpSocket.RegisterCompress method
// - DataRawByteStringtype should be a generic AnsiString/RawByteString, which
// should be in practice a SockString or a RawByteString
THttpSocketCompress = function(var DataRawByteString; Compress: boolean): AnsiString;
/// used to maintain a list of known compression algorithms
THttpSocketCompressRec = record
/// the compression name, as in ACCEPT-ENCODING: header (gzip,deflate,synlz)
Name: SockString;
/// the function handling compression and decompression
Func: THttpSocketCompress;
/// the size in bytes after which compress will take place
// - will be 1024 e.g. for 'zip' or 'deflate'
// - could be 0 e.g. when encrypting the content, meaning "always compress"
CompressMinSize: integer;
end;
/// list of known compression algorithms
THttpSocketCompressRecDynArray = array of THttpSocketCompressRec;
/// identify some items in a list of known compression algorithms
THttpSocketCompressSet = set of 0..31;
/// parent of THttpClientSocket and THttpServerSocket classes
// - contain properties for implementing HTTP/1.1 using the Socket API
// - handle chunking of body content
// - can optionaly compress and uncompress on the fly the data, with
// standard gzip/deflate or custom (synlzo/synlz) protocols
THttpSocket = class(TCrtSocket)
protected
/// true if the TRANSFER-ENCODING: CHUNKED was set in headers
Chunked: boolean;
/// to call GetBody only once
fBodyRetrieved: boolean;
/// used by RegisterCompress method
fCompress: THttpSocketCompressRecDynArray;
/// set by RegisterCompress method
fCompressAcceptEncoding: SockString;
/// GetHeader set index of protocol in fCompress[], from ACCEPT-ENCODING:
fCompressHeader: THttpSocketCompressSet;
/// same as HeaderGetValue('CONTENT-ENCODING'), but retrieved during Request
// and mapped into the fCompress[] array
fContentCompress: integer;
/// cache for HeaderGetText
fHeaderText: SockString;
/// compress the data, adding corresponding headers via SockSend()
// - always add a 'Content-Length: ' header entry (even if length=0)
// - e.g. 'Content-Encoding: synlz' header if compressed using synlz
// - and if Data is not '', will add 'Content-Type: ' header
procedure CompressDataAndWriteHeaders(const OutContentType: SockString;
var OutContent: SockString);
public
/// TCP/IP prefix to mask HTTP protocol
// - if not set, will create full HTTP/1.0 or HTTP/1.1 compliant content
// - in order to make the TCP/IP stream not HTTP compliant, you can specify
// a prefix which will be put before the first header line: in this case,
// the TCP/IP stream won't be recognized as HTTP, and will be ignored by
// most AntiVirus programs, and increase security - but you won't be able
// to use an Internet Browser nor AJAX application for remote access any more
TCPPrefix: SockString;
/// will contain the first header line:
// - 'GET /path HTTP/1.1' for a GET request with THttpServer, e.g.
// - 'HTTP/1.0 200 OK' for a GET response after Get() e.g.
Command: SockString;
/// will contain the header lines after a Request
// - use HeaderGetValue() to get one HTTP header item value by name
Headers: TSockStringDynArray;
/// will contain the data retrieved from the server, after the Request
Content: SockString;
/// same as HeaderGetValue('CONTENT-LENGTH'), but retrieved during Request
// - is overridden with real Content length during HTTP body retrieval
ContentLength: integer;
/// same as HeaderGetValue('CONTENT-TYPE'), but retrieved during Request
ContentType: SockString;
/// same as HeaderGetValue('CONNECTION')='Close', but retrieved during Request
ConnectionClose: boolean;
/// same as HeaderGetValue('CONNECTION')='Upgrade', but retrieved during Request
ConnectionUpgrade: boolean;
/// retrieve the HTTP headers into Headers[] and fill most properties below
procedure GetHeader;
/// retrieve the HTTP body (after uncompression if necessary) into Content
procedure GetBody;
/// add an header entry, returning the just entered entry index in Headers[]
function HeaderAdd(const aValue: SockString): integer;
/// set all Header values at once, from CRLF delimited text
procedure HeaderSetText(const aText: SockString;
const aForcedContentType: SockString='');
/// get all Header values at once, as CRLF delimited text
// - you can optionally specify a value to be added as 'RemoteIP: ' header
function HeaderGetText(const aRemoteIP: SockString=''): SockString;
/// HeaderGetValue('CONTENT-TYPE')='text/html', e.g.
// - supplied aUpperName should be already uppercased
function HeaderGetValue(const aUpperName: SockString): SockString;
/// will register a compression algorithm
// - used e.g. to compress on the fly the data, with standard gzip/deflate
// or custom (synlzo/synlz) protocols
// - returns true on success, false if this function or this
// ACCEPT-ENCODING: header was already registered
// - you can specify a minimal size (in bytes) before which the content won't
// be compressed (1024 by default, corresponding to a MTU of 1500 bytes)
// - the first registered algorithm will be the prefered one for compression
function RegisterCompress(aFunction: THttpSocketCompress;
aCompressMinSize: integer=1024): boolean;
end;
THttpServer = class;
/// Socket API based HTTP/1.1 server class used by THttpServer Threads
THttpServerSocket = class(THttpSocket)
protected
fMethod: SockString;
fURL: SockString;
fKeepAliveClient: boolean;
fRemoteIP: SockString;
fRemoteConnectionID: Int64;
fServer: THttpServer;
public
/// create the socket according to a server
// - will register the THttpSocketCompress functions from the server
constructor Create(aServer: THttpServer); reintroduce;
/// main object function called after aClientSock := Accept + Create:
// - get initialize the socket with the supplied accepted socket
// - caller will then use the GetRequest method below to
// get the request
procedure InitRequest(aClientSock: TSocket);
/// main object function called after aClientSock := Accept + Create:
// - get Command, Method, URL, Headers and Body (if withBody is TRUE)
// - get sent data in Content (if ContentLength<>0)
// - return false if the socket was not connected any more, or if
// any exception occured during the process
function GetRequest(withBody: boolean; headerMaxTix: Int64): boolean;
/// contains the method ('GET','POST'.. e.g.) after GetRequest()
property Method: SockString read fMethod;
/// contains the URL ('/' e.g.) after GetRequest()
property URL: SockString read fURL;
/// true if the client is HTTP/1.1 and 'Connection: Close' is not set
// - default HTTP/1.1 behavior is "keep alive", unless 'Connection: Close'
// is specified, cf. RFC 2068 page 108: "HTTP/1.1 applications that do not
// support persistent connections MUST include the "close" connection option
// in every message"
property KeepAliveClient: boolean read fKeepAliveClient write fKeepAliveClient;
/// the recognized client IP, after a call to GetRequest()
property RemoteIP: SockString read fRemoteIP;
/// the recognized connection ID, after a call to GetRequest()
property RemoteConnectionID: Int64 read fRemoteConnectionID;
end;
/// Socket API based REST and HTTP/1.1 compatible client class
// - this component is HTTP/1.1 compatible, according to RFC 2068 document
// - the REST commands (GET/POST/PUT/DELETE) are directly available
// - open connection with the server with inherited Open(server,port) function
// - if KeepAlive>0, the connection is not broken: a further request (within
// KeepAlive milliseconds) will use the existing connection if available,
// or recreate a new one if the former is outdated or reset by server
// (will retry only once); this is faster, uses less resources (especialy
// under Windows), and is the recommended way to implement a HTTP/1.1 server
// - on any error (timeout, connection closed) will retry once to get the value
// - don't forget to use Free procedure when you are finished
THttpClientSocket = class(THttpSocket)
protected
fUserAgent: SockString;
fProcessName: SockString;
procedure RequestSendHeader(const url, method: SockString); virtual;
public
/// common initialization of all constructors
// - this overridden method will set the UserAgent with some default value
// - you can customize the default client timeouts by setting appropriate
// aTimeout parameters (in ms) if you left the 0 default parameters,
// it would use global HTTP_DEFAULT_RECEIVETIMEOUT variable values
constructor Create(aTimeOut: PtrInt=0); override;
/// low-level HTTP/1.1 request
// - called by all Get/Head/Post/Put/Delete REST methods
// - after an Open(server,port), return 200,202,204 if OK, http status error otherwise
// - retry is false by caller, and will be recursively called with true to retry once
function Request(const url, method: SockString; KeepAlive: cardinal;
const header, Data, DataType: SockString; retry: boolean): integer; virtual;
/// after an Open(server,port), return 200 if OK, http status error otherwise
// - get the page data in Content
function Get(const url: SockString; KeepAlive: cardinal=0; const header: SockString=''): integer;
/// after an Open(server,port), return 200 if OK, http status error otherwise
// - get the page data in Content
// - if AuthToken<>'', will add an header with 'Authorization: Bearer '+AuthToken
function GetAuth(const url, AuthToken: SockString; KeepAlive: cardinal=0): integer;
/// after an Open(server,port), return 200 if OK, http status error otherwise - only
// header is read from server: Content is always '', but Headers are set
function Head(const url: SockString; KeepAlive: cardinal=0; const header: SockString=''): integer;
/// after an Open(server,port), return 200,201,204 if OK, http status error otherwise
function Post(const url, Data, DataType: SockString; KeepAlive: cardinal=0;
const header: SockString=''): integer;
/// after an Open(server,port), return 200,201,204 if OK, http status error otherwise
function Put(const url, Data, DataType: SockString; KeepAlive: cardinal=0;
const header: SockString=''): integer;
/// after an Open(server,port), return 200,202,204 if OK, http status error otherwise
function Delete(const url: SockString; KeepAlive: cardinal=0; const header: SockString=''): integer;
/// by default, the client is identified as IE 5.5, which is very
// friendly welcome by most servers :(
// - you can specify a custom value here
property UserAgent: SockString read fUserAgent write fUserAgent;
/// the associated process name
property ProcessName: SockString read fProcessName write fProcessName;
end;
/// class-reference type (metaclass) of a HTTP client socket access
// - may be either THttpClientSocket or THttpClientWebSockets (from
// SynBidirSock unit)
THttpClientSocketClass = class of THttpClientSocket;
{$ifndef LVCL}
/// event prototype used e.g. by THttpServerGeneric.OnHttpThreadStart
TNotifyThreadEvent = procedure(Sender: TThread) of object;
{$endif}
{$M+}
TSynThreadPool = class;
/// a simple TThread with a "Terminate" event run in the thread context
// - the TThread.OnTerminate event is run within Synchronize() so did not
// match our expectations to be able to release the resources in the thread
// context which created them (e.g. for COM objects, or some DB drivers)
// - used internally by THttpServerGeneric.NotifyThreadStart() - you should
// not have to use the protected fOnTerminate event handler
// - also define a Start method for compatibility with older versions of Delphi
TSynThread = class(TThread)
protected
// ensure fOnTerminate is called only if NotifyThreadStart has been done
fStartNotified: TObject;
{$ifndef LVCL} // already available in LVCL
// we re-defined an fOnTerminate event which would be run in the terminated
// thread context (whereas TThread.OnTerminate is called in the main thread)
// -> see THttpServerGeneric.OnHttpThreadTerminate event property
fOnTerminate: TNotifyThreadEvent;
procedure DoTerminate; override;
{$endif}
public
/// initialize the server instance, in non suspended state
constructor Create(CreateSuspended: boolean); reintroduce; virtual;
{$ifndef HASTTHREADSTART}
/// method to be called when the thread was created as suspended
// - Resume is deprecated in the newest RTL, since some OS - e.g. Linux -
// do not implement this pause/resume feature
// - we define here this method for older versions of Delphi
procedure Start;
{$endif}
/// safe version of Sleep() which won't break the thread process
// - returns TRUE if the thread was Terminated
// - returns FALSE if successfully waited up to MS milliseconds
function SleepOrTerminated(MS: cardinal): boolean;
/// defined as public since may be used to terminate the processing methods
property Terminated;
end;
{$M-}
/// HTTP response Thread as used by THttpServer Socket API based class
// - Execute procedure get the request and calculate the answer
// - you don't have to overload the protected THttpServerResp Execute method:
// override THttpServer.Request() function or, if you need a lower-level access
// (change the protocol, e.g.) THttpServer.Process() method itself
THttpServerResp = class(TSynThread)
protected
fServer: THttpServer;
fServerSock: THttpServerSocket;
fClientSock: TSocket;
fConnectionID: integer;
/// main thread loop: read request from socket, send back answer
procedure Execute; override;
public
/// initialize the response thread for the corresponding incoming socket
// - this version will get the request directly from an incoming socket
constructor Create(aSock: TSocket; aServer: THttpServer); reintroduce; overload;
/// initialize the response thread for the corresponding incoming socket
// - this version will handle KeepAlive, for such an incoming request
constructor Create(aServerSock: THttpServerSocket; aServer: THttpServer);
reintroduce; overload; virtual;
/// the associated socket to communicate with the client
property ServerSock: THttpServerSocket read fServerSock;
/// the associated main HTTP server instance
property Server: THttpServer read fServer;
/// the unique identifier of this connection
property ConnectionID: integer read fConnectionID;
end;
/// metaclass of HTTP response Thread
THttpServerRespClass = class of THttpServerResp;
{$ifdef MSWINDOWS}
// I/O completion ports API is the best option under Windows
// under Linux/POSIX, we fallback to a classical event-driven pool
{$define USE_WINIOCP}
{$endif MSWINDOWS}
/// defines the sub-threads used by TSynThreadPool
TSynThreadPoolSubThread = class(TSynThread)
protected
fOwner: TSynThreadPool;
fNotifyThreadStartName: AnsiString;
fThreadNumber: integer;
{$ifndef USE_WINIOCP}
fProcessingContext: pointer;
fEvent: TEvent;
{$endif USE_WINIOCP}
procedure NotifyThreadStart(Sender: TSynThread);
procedure DoTask(Context: pointer); // exception-safe call of fOwner.Task()
public
/// initialize the thread
constructor Create(Owner: TSynThreadPool); reintroduce;
/// finalize the thread
destructor Destroy; override;
/// will loop for any pending task, and execute fOwner.Task()
procedure Execute; override;
end;
{$M+}
/// a simple Thread Pool, used e.g. for fast handling HTTP requests
// - implemented over I/O Completion Ports under Windows, or a classical
// Event-driven approach under Linux/POSIX
TSynThreadPool = class
protected
fSubThread: TObjectList; // holds TSynThreadPoolSubThread
fRunningThreads: integer;
fExceptionsCount: integer;
fOnTerminate: TNotifyThreadEvent;
fOnThreadStart: TNotifyThreadEvent;
fTerminated: boolean;
{$ifdef USE_WINIOCP}
fRequestQueue: THandle;
{$else}
fQueuePendingContext: boolean;
fPendingContext: array of pointer;
fPendingContextCount: integer;
fSafe: TRTLCriticalSection;
function GetPendingContextCount: integer;
function PopPendingContext: pointer;
function QueueLength: integer; virtual;
{$endif USE_WINIOCP}
/// end thread on IO error
function NeedStopOnIOError: boolean; virtual;
/// process to be executed after notification
procedure Task(aCaller: TSynThread; aContext: Pointer); virtual; abstract;
procedure TaskAbort(aContext: Pointer); virtual;
public
/// initialize a thread pool with the supplied number of threads
// - abstract Task() virtual method will be called by one of the threads
// - up to 256 threads can be associated to a Thread Pool
// - can optionaly accept aOverlapHandle - a handle previously
// opened for overlapped I/O (IOCP) under Windows
// - aQueuePendingContext=true will store the pending context into
// an internal queue, so that Push() always returns true
constructor Create(NumberOfThreads: Integer=32;
{$ifdef USE_WINIOCP}aOverlapHandle: THandle=INVALID_HANDLE_VALUE
{$else}aQueuePendingContext: boolean=false{$endif});
/// shut down the Thread pool, releasing all associated threads
destructor Destroy; override;
/// let a task (specified as a pointer) be processed by the Thread Pool
// - returns false if there is no idle thread available in the pool and
// Create(aQueuePendingContext=false) was used (caller should retry later);
// if aQueuePendingContext was true in Create, the supplied context will