1016 lines
42 KiB
C
1016 lines
42 KiB
C
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// !!! PipeCount needs a critical section?
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/* Send a list of files across the named pipe as fast as possible
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*
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* The overall organisation:
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*
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* Sumserve receives requests over a named pipe. (See sumserve.h)
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* The requests can be for details of files or for the files
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* themselves. File details involve sending relatively small
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* quantities of data and therefore no attempt is made to
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* double-buffer or overlap execution.
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*
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* For a send-files request (SSREQ_FILES), the data is typically large,
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* and can be a whole NT build which means sending hundreds
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* of megabytes. Such a transfer can take literally days and
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* so optimisation to achieve maximum throughput is essential.
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*
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* To maximise throughput
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* 1. The data is packed before sending
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* 2. One thread per pipe does almost nothing except send data through
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* its pipe with all other work being done on other threads.
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*
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* Because we have had trouble with bad files being transmitted over
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* the network, we checksum each file. Windiff requires that we
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* do a scan first before doing a copy, so we already have checksums.
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* All we need to do is to check the newly received files.
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* LATER: We should not require checksums in advance. The checksuming
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* could be done by (yet another) pass, created if need be. An extra
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* flag could be added to the request to indicate "send checksums".
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*
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* The packing is done by a separate program that reads from a file and
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* writes to a file. This means that we get three lots of file I/O
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* (read; write; read) before the file is sent. For a small
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* file the disk cacheing may eliminate this, for a large file we
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* probably pay the price. A possible future enhancement is therefore
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* to rewrite the packing to do it in-storage so that the file is read
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* once only. In the meantime we run threads to overlap the packing
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* with the sending of the previous file(s).
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*
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* The main program sets up a named pipe which a client connects to.
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* This is necessary because pipes are only half-duplex. i.e. the
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* following hangs:
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* client read; server read; client write;
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* The write hangs waiting for the client read. We broadly speaking have one
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* pipe running in each direction.
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*
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* To eliminate the overhead of setting up a virtual circuit for each
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* file request there is a request code to send a list of files.
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* The protocol (for the control pipe) is then as follows:
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* 1. Typical session:
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* CLIENT SERVER
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* ----<SSREQ_FILES------------------>
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* <------(SSRESP_PIPENAME,pipename)--
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* ----<SSREQ_NEXTFILE,filename>----->
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* ----<SSREQ_NEXTFILE,filename>----->
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* ...
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* --------<SSREQ_ENDFILES>---------->
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*
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* Meanwhile, asynchronously with this, the data goes back the other way like
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*
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* CLIENT SERVER
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* <-----<SSNEWRESP>----------
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* <---<1 or more SSNEWPACK>--
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...
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* <-----<SSNEWRESP>----------
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* <---<1 or more SSNEWPACK>--
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* ...
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* <-----<End>----------------
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*
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* Even a zero length file gets 1 SSNEWPACK record.
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* An Erroneous file (can't read etc) gets no SSNEWPACKs and a negative lCode
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* in its SSNEWRESP.
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* A file that goes wrong during read-in gets a packet length code of -1 or -2.
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* The end of the sequence of SSNEWPACKs is signalled by a shorter
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* than maximum length one. If the file is EXACTLY n buffers long
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* then an extra SSNEWPACK with zero bytes of data comes on the end.
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*
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* The work is broken into the following threads:
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* Control thread (ss_sendfiles):
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* Receives lists of files to be sent
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* Creates pipes for the actual transmission
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* Creates queues (see below. Queue parameters must match pipes)
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* Puts filenames onto first queue
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* Destroys first queue at end.
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* Packing thread
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* Takes file details from the packing queue
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* Packs the file (to create a temporary file)
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* Puts the file details (including the temp name) onto the reading queue
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* Destroys the reading queue at the end
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* Reading thread
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* Takes the file details from the reading queue
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* Splits the file into a header and a list of data packets
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* and enqueues each of these on the Sending thread.
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* (Note this means no more than one reading thread to be running).
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* Erases the temp file
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* Destroys the sending queue at the end
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* Sending thread
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* Takes the things from the sending thread and sends them
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*
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* This whole scheme can be running for multiple clients, so we
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* need some instance data that defines which pipeline we are
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* running. This is held in the instance data of the QUEUEs that
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* are created (retrieved by the queue emptiers by Queue_GetInstanceData).
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* The instance data at each stage is the handle of the following stage
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* i.e. the next QUEUE, or the hpipe of the data pipe for the last stage.
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* The current design only allows for one data pipe. If we have
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* multiple data pipes then we need to solve the following problems:
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* 1. Communication of the number and names of the data pipes
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* to the client (presumably across the control thread.
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* 2. Error handling
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* 3. Balancing the load between the pipes
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*
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* NORMAL SHUTDOWN:
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* After the last element has been Put to the first Queue the main thread
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* calls Queue_Destroy to destroy the first queue. This will result in
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* the queue being destroyed BUT NOT UNTIL THE LAST ELEMENT HAS BEEN GOT.
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* When the last packing thread gets its ENDQUEUE it calls Queue_Destroy
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* to destroy the next queue, and so on down the line.
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*
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* ERROR RECOVERY
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* Errors can occur at almost any stage.
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* The obvious implementation of having a global BOOL that tells
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* whether a disaster has happened won't work because there
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* could be multiple clients and only one of them with a disaster.
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*
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* An error in a single file is propagated forwards to the client end.
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* An error in the whole mechanism (net blown away) can mean that the
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* whole thing needs to be shut down. In this case the error must
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* be propagated backwards. That works as follows:
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* The Sending thread Queue_Aborts the SendQueue which it was Getting from.
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* This results in Puts to this queue returning FALSE.
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* Case 1. There are no more Puts anyway:
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* We are on the last file, the filling thread was about to Destroy the
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* queue anyway. It does so.
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* Case 2. The next Put gets a FALSE return code.
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* The thread attempting the Put does a Queue_Destroy on its output
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* queue and a Queue_Abort on its input queue.
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* This propagates all the way back until either the first queue
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* is aborted or it reaches a queue that was being destroyed anyway.
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* See Queue.h
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* Once the Putting thread has done a Destroy on its output queue,
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* the threads Getting from it (which are still running, even if
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* they did the Abort) get STOPTHREAD/ENDQUEUE back from a Get. The last Get
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* to a queue that has had a Queue_Destroy done on it has a side effect
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* of actually deallocating the queue. In our case we only have one
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* Getting thread, so what happens is that it Queue_Aborts the queue
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* and then does a Queue_Get which WAITs. When the Queue_Destroy comes in
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* from the Putting thread, this releases the WAITing Getting thread which
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* then actually deallocates the Queue.
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*
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* You can also get shutdown happening from both ends at once. This happens
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* when the control thread's pipe goes down getting names and the sending pipe
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* also breaks. (e.g. general net collapse or client aborted).
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*/
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#include <windows.h>
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#include <stdio.h>
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#include <string.h>
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#include <gutils.h>
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#include "sumserve.h"
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#include "errlog.h"
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#include "server.h"
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#include "queue.h"
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#if DBG
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#define STATIC // allow for debug.
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#else
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#define STATIC static
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#endif
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/* SOCKETS / NAMED PIPES macros
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*/
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#ifdef SOCKETS
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#define CLOSEHANDLE( handle ) closesocket( handle )
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#define TCPPORT 1024
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#else
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#define CLOSEHANDLE( handle ) CloseHandle( handle )
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#endif
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//////////////ULONG ss_checksum_block(PSTR block, int size);
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#define PIPEPREFIX "Sdpx" // for making an unlikely pipe name
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static PipeCount = 0; // for making pipe names unique.
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/* structure for recording all we need to know about a file as it
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* progresses along the chain of pipes */
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typedef struct {
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FILETIME ft_create;
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FILETIME ft_lastaccess;
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FILETIME ft_lastwrite;
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DWORD fileattribs;
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DWORD SizeHi; /* Anticipating files larger that 4GB! */
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DWORD SizeLo; /* Anticipating files larger that 4GB! */
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int ErrorCode;
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long Checksum; /* Uunused except for debug. */
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char TempName[MAX_PATH]; /* name of packed file at server */
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char Path[MAX_PATH]; /* name of file to fetch */
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char LocalName[MAX_PATH]; /* name of file at client end */
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} FILEDETAILS;
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/* forward declarations for procedures */
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STATIC int PackFile(QUEUE Queue);
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STATIC int ReadInFile(QUEUE Queue);
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STATIC int SendData(QUEUE Queue);
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STATIC void PurgePackedFiles(PSTR Ptr, int Len);
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STATIC BOOL EnqueueName(QUEUE Queue, LPSTR Path, UINT BuffLen);
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STATIC BOOL AddFileAttributes(FILEDETAILS * fd);
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static void Error(PSTR Title)
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{
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dprintf1(("Error %d from %s when creating data pipe.\n", GetLastError(), Title));
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}
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/* ss_sendfiles:
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Send a response naming the data pipe, collect further names
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from further client messages, all according to the protocol above.
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Start the data pipe and arrange that all the files are sent
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by getting them all enqueued on the first queue.
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Destroy PackQueue at the end. Arrange for the other queues
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to be destroyed by the usual Queue mechanism, or destroy them
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explicitly if they never get started.
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*/
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BOOL
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ss_sendfiles(HANDLE hPipe, long lVersion)
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{ /* Create the queues and set about filling the first one */
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QUEUE PackQueue, ReadQueue, SendQueue;
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#ifdef SOCKETS
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SOCKET hpSend;
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static BOOL SocketsInitialized = FALSE;
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#else
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HANDLE hpSend; /* the data pipe */
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#endif /* SOCKETS */
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char PipeName[80]; /* The name of the new data pipe */
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BOOL Started = FALSE; /* TRUE if something enqueued */
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#ifdef SOCKETS
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if( !SocketsInitialized )
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{
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WSADATA WSAData;
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if( ( WSAStartup( MAKEWORD( 1, 1 ), &WSAData ) ) == 0 )
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{
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SocketsInitialized = TRUE;
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}
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else
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{
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printf("WSAStartup failed");
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}
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}
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#endif
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{
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/****************************************
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We need security attributes for the pipe to let anyone other than the
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current user log on to it.
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***************************************/
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/* Allocate DWORDs for the ACL to get them aligned. Round up to next DWORD above */
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DWORD Acl[(sizeof(ACL)+sizeof(ACCESS_ALLOWED_ACE)+3)/4+4]; // + 4 by experiment!!
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SECURITY_DESCRIPTOR sd;
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PSECURITY_DESCRIPTOR psd = &sd;
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PSID psid;
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SID_IDENTIFIER_AUTHORITY SidWorld = SECURITY_WORLD_SID_AUTHORITY;
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PACL pacl = (PACL)(&(Acl[0]));
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SECURITY_ATTRIBUTES sa;
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if (!AllocateAndInitializeSid( &SidWorld, 1, SECURITY_WORLD_RID
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, 1, 2, 3, 4, 5, 6, 7
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, &psid
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)
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) {
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Error("AllocateAndInitializeSid");
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return FALSE;
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}
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if (!InitializeAcl(pacl, sizeof(Acl), ACL_REVISION)){
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Error("InitializeAcl");
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return FALSE;
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}
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if (!AddAccessAllowedAce(pacl, ACL_REVISION, GENERIC_WRITE|GENERIC_READ, psid)){
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Error("AddAccessAllowedAce");
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return FALSE;
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}
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if (!InitializeSecurityDescriptor(psd, SECURITY_DESCRIPTOR_REVISION)){
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Error("InitializeSecurityDescriptor");
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return FALSE;
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}
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if (!SetSecurityDescriptorDacl(psd, TRUE, pacl, FALSE)){
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Error("SetSecurityDescriptorDacl");
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return FALSE;
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}
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sa.nLength = sizeof(sa);
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sa.lpSecurityDescriptor = psd;
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sa.bInheritHandle = TRUE;
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/* We now have a good security descriptor! */
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/* Create the (new, unique) name of the pipe and then create the pipe */
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/* I am finding it hard to decide whether the following line (++PpipeCount)
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actually needs a critical section or not. The worst that could happen
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would be that we got an attempt to create a pipe with an existing name.
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*/
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++PipeCount;
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sprintf(PipeName, "\\\\.\\pipe\\%s%d", PIPEPREFIX, PipeCount);
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#ifdef SOCKETS
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if (!ss_sendnewresp( hPipe, SS_VERSION, SSRESP_PIPENAME
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, 0, 0, 0, TCPPORT, "")) {
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dprintf1(( "Failed to send response on pipe %x naming new pipe.\n"
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, hPipe));
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return FALSE; /* Caller will close hPipe */
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}
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if( !SocketListen( TCPPORT, &hpSend ) )
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{
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dprintf1(("Could not create socket\n"));
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return FALSE;
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}
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FreeSid(psid);
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#else
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hpSend = CreateNamedPipe(PipeName, /* pipe name */
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PIPE_ACCESS_DUPLEX, /* both read and write */
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PIPE_WAIT|PIPE_TYPE_MESSAGE|PIPE_READMODE_MESSAGE,
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1, /* at most one instance */
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10000, /* sizeof(SSNEWPACK) + some for luck */
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0, /* dynamic inbound buffer allocation */
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5000, /* def. timeout 5 seconds */
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&sa /* security descriptor */
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);
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FreeSid(psid);
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if (hpSend == INVALID_HANDLE_VALUE) {
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dprintf1(("Could not create named data pipe\n"));
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return FALSE;
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}
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dprintf1(("Data pipe %x called '%s' created for main pipe %x.\n", hpSend, PipeName, hPipe));
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#endif /* SOCKETS */
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}
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/* Send the response which names the data pipe */
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#ifndef SOCKETS
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if (!ss_sendnewresp( hPipe, SS_VERSION, SSRESP_PIPENAME
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, 0, 0, 0, 0, PipeName)) {
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dprintf1(( "Failed to send response on pipe %x naming new pipe.\n"
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, hPipe));
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CLOSEHANDLE(hpSend);
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return FALSE; /* Caller will close hPipe */
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}
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if (!ConnectNamedPipe(hpSend, NULL)) {
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CLOSEHANDLE(hpSend);
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return FALSE;
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}
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#endif /* NOT SOCKETS */
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//dprintf1(("Client connected to data pipe -- here we go...\n"));
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/* Create all the queues: Allow up to 10K file names to be queued
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up to 10 files to be packed in advance and 6 buffers of data to be
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read into main storage in advance:
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proc MxMT MnQS MxQ Event InstData Name*/
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SendQueue = Queue_Create(SendData, 1, 0, 6, NULL, (DWORD)hpSend, "SendQueue");
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ReadQueue = Queue_Create(ReadInFile, 1, 0, 10, NULL, (DWORD)SendQueue, "ReadQueue");
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PackQueue = Queue_Create(PackFile, 3, 0, 99999, NULL, (DWORD)ReadQueue, "PackQueue");
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/* Abort unless it all worked */
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if (PackQueue==NULL || ReadQueue==NULL || SendQueue==NULL) {
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dprintf1(("Queues for pipe %x failed to Create. Aborting...\n", hPipe));
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if (PackQueue) Queue_Destroy(PackQueue);
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if (ReadQueue) Queue_Destroy(ReadQueue);
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if (SendQueue) Queue_Destroy(SendQueue);
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CLOSEHANDLE(hpSend);
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return FALSE; /* Caller will close hPipe */
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}
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/* Collect names from client and enqueue each one */
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for (; ; )
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{ SSNEWREQ Request; /* message from client */
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DWORD ActSize; /* bytes read from (main) pipe */
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if (ReadFile(hPipe, &Request, sizeof(Request), &ActSize, NULL)){
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if (Request.lVersion>SS_VERSION) {
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dprintf1(("Bad version %d in file list request on pipe %x\n"
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, Request.lVersion, hPipe));
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break;
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}
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if (Request.lRequest!=LREQUEST) {
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dprintf1(("Bad LREQUEST from pipe %x\n", hPipe));
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break;
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}
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||
|
if (Request.lCode == -SSREQ_ENDFILES) {
|
||
|
dprintf1(("End of client's files list on pipe %x\n", hPipe));
|
||
|
|
||
|
/* This is the clean way to end */
|
||
|
Queue_Destroy(PackQueue);
|
||
|
if (!Started) {
|
||
|
/* OK - so the clever clogs requested zero files */
|
||
|
Queue_Destroy(ReadQueue);
|
||
|
Queue_Destroy(SendQueue);
|
||
|
/* Send a No More Files response */
|
||
|
#ifdef SOCKETS
|
||
|
{
|
||
|
SSNEWRESP resp;
|
||
|
|
||
|
resp.lVersion = SS_VERSION;
|
||
|
resp.lResponse = LRESPONSE;
|
||
|
resp.lCode = SSRESP_END;
|
||
|
resp.ulSize = 0;
|
||
|
resp.ulSum = 0;
|
||
|
resp.ft_lastwrite.dwLowDateTime = 0;
|
||
|
resp.ft_lastwrite.dwHighDateTime = 0;
|
||
|
|
||
|
send(hpSend, (PSTR) &resp, sizeof(resp), 0);
|
||
|
}
|
||
|
#else
|
||
|
ss_sendnewresp( hpSend, SS_VERSION, SSRESP_END
|
||
|
, 0,0, 0,0, NULL);
|
||
|
#endif /* SOCKETS */
|
||
|
CLOSEHANDLE(hpSend);
|
||
|
}
|
||
|
return TRUE;
|
||
|
}
|
||
|
if (Request.lCode != -SSREQ_NEXTFILE) {
|
||
|
|
||
|
dprintf1(( "Bad code (%d) in files list from pipe %x\n"
|
||
|
, Request.lCode, hPipe));
|
||
|
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
else { DWORD errorcode = GetLastError();
|
||
|
switch(errorcode) {
|
||
|
|
||
|
case ERROR_NO_DATA:
|
||
|
case ERROR_BROKEN_PIPE:
|
||
|
/* pipe connection lost - forget it */
|
||
|
dprintf1(("main pipe %x broken on read\n", hPipe));
|
||
|
break;
|
||
|
default:
|
||
|
dprintf1(("read error %d on main pipe %x\n", errorcode, hPipe));
|
||
|
break;
|
||
|
}
|
||
|
break;
|
||
|
}
|
||
|
if (!EnqueueName( PackQueue, Request.szPath
|
||
|
, (UINT)((LPBYTE)(&Request) + ActSize - (LPBYTE)(&Request.szPath))
|
||
|
)
|
||
|
){
|
||
|
break;
|
||
|
}
|
||
|
Started = TRUE;
|
||
|
} /* loop */
|
||
|
|
||
|
/* only exit this way on error */
|
||
|
/* Close the queues down. Allow what's in them to run through */
|
||
|
Queue_Destroy(PackQueue);
|
||
|
if (!Started) {
|
||
|
Queue_Destroy(ReadQueue);
|
||
|
Queue_Destroy(SendQueue);
|
||
|
|
||
|
}
|
||
|
return FALSE;
|
||
|
} /* ss_sendfiles */
|
||
|
|
||
|
|
||
|
/* Attempt to Queue.Put Path onto Queue as a FILEDETAILS
|
||
|
with default values for all other fields.
|
||
|
Return TRUE or FALSE according as it succeeded.
|
||
|
*/
|
||
|
STATIC BOOL EnqueueName(QUEUE Queue, LPSTR Path, UINT BuffLen)
|
||
|
{
|
||
|
FILEDETAILS fd;
|
||
|
|
||
|
/* unpack Path and LocalName from "superstring" */
|
||
|
strcpy(fd.Path, Path);
|
||
|
BuffLen -= (strlen(Path)+1);
|
||
|
if (BuffLen<0) return FALSE; // Uh oh! strlen just looked at garbage.
|
||
|
Path += strlen(Path)+1;
|
||
|
BuffLen -= (strlen(Path)+1);
|
||
|
if (BuffLen<0) return FALSE; // Uh oh! strlen just looked at garbage.
|
||
|
strcpy(fd.LocalName, Path);
|
||
|
|
||
|
/* set defaults for every field */
|
||
|
fd.ErrorCode = 0;
|
||
|
fd.ft_lastwrite.dwLowDateTime = 0;
|
||
|
fd.ft_lastwrite.dwHighDateTime = 0;
|
||
|
fd.ft_create.dwLowDateTime = 0;
|
||
|
fd.ft_create.dwHighDateTime = 0;
|
||
|
fd.ft_lastaccess.dwLowDateTime = 0;
|
||
|
fd.ft_lastaccess.dwHighDateTime = 0;
|
||
|
fd.fileattribs = 0;
|
||
|
fd.SizeHi = 0;
|
||
|
fd.SizeLo = 0;
|
||
|
fd.Checksum = 0;
|
||
|
fd.TempName[0] = '\0';
|
||
|
|
||
|
if(!Queue_Put(Queue, (LPBYTE)&fd, sizeof(fd))){
|
||
|
dprintf1(("Put to pack queue failed\n"));
|
||
|
return FALSE;
|
||
|
}
|
||
|
return TRUE;
|
||
|
} /* EnqueueName */
|
||
|
|
||
|
|
||
|
/* Dequeue elements from Queue, pack them and enqueue them on the next
|
||
|
queue whose queue handle is the InstanceData of Queue.
|
||
|
The ErrorCode in fd when Dequeued must be 0. ??? Incautious?
|
||
|
Destroy the output queue at the end.
|
||
|
On a serious error, Queue_Abort Queue and Queue_Destroy the output queue.
|
||
|
*/
|
||
|
STATIC int PackFile(QUEUE Queue)
|
||
|
{
|
||
|
FILEDETAILS fd; /* the queue element processed */
|
||
|
QUEUE OutQueue;
|
||
|
BOOL Aborting = FALSE; /* TRUE means input has been aborted (probably output is sick) */
|
||
|
DWORD ThreadId;
|
||
|
ThreadId = GetCurrentThreadId();
|
||
|
|
||
|
dprintf1(("File packer %d starting \n", ThreadId)); // can't quote hPipe, don't know it
|
||
|
OutQueue = (QUEUE)Queue_GetInstanceData(Queue);
|
||
|
|
||
|
for (; ; )
|
||
|
{ int rc; /* return code from Queue_Get */
|
||
|
|
||
|
rc = Queue_Get(Queue, (LPBYTE)&fd, sizeof(fd));
|
||
|
if (rc==ENDQUEUE) {
|
||
|
dprintf1(("Packing thread %d ending.\n", ThreadId));
|
||
|
Queue_Destroy(OutQueue);
|
||
|
// dprintf1(("%d has done Queue_Destroy on ReadQueue.\n", ThreadId));
|
||
|
ExitThread(0);
|
||
|
}
|
||
|
if (rc==STOPTHREAD) {
|
||
|
dprintf1(("%d, a packing thread ending.\n", ThreadId));
|
||
|
ExitThread(0);
|
||
|
}
|
||
|
else if (rc<0) {
|
||
|
dprintf1(( "Packing thread %d aborting. Bad return code %d from Get.\n"
|
||
|
, ThreadId, rc));
|
||
|
if (Aborting) break; /* Touch nothing, just quit! */
|
||
|
Queue_Abort(Queue, NULL);
|
||
|
continue; /* Next Queue_Get destroys Queue */
|
||
|
}
|
||
|
|
||
|
|
||
|
/* First add the file attributes to fd */
|
||
|
AddFileAttributes(&fd);
|
||
|
/* no need to look at return code fd.ErrorCode tells all */
|
||
|
|
||
|
/* create temp filename */
|
||
|
if ( 0 != fd.ErrorCode
|
||
|
|| 0==GetTempPath(sizeof(fd.TempName), fd.TempName)
|
||
|
|| 0==GetTempFileName(fd.TempName, "sum", 0, fd.TempName)
|
||
|
)
|
||
|
fd.ErrorCode = SSRESP_NOTEMPPATH;
|
||
|
|
||
|
/* Pack into temp file */
|
||
|
if (fd.ErrorCode==0) {
|
||
|
BOOL bOK = FALSE;
|
||
|
|
||
|
//dprintf1(("%d Compressing file '%s' => '%s'\n", ThreadId, fd.Path, fd.TempName));
|
||
|
|
||
|
/* compress the file into this temporary file
|
||
|
Maybe it will behave badly if there's a large file or
|
||
|
no temp space or something...
|
||
|
*/
|
||
|
try{
|
||
|
if (!ss_compress(fd.Path, fd.TempName)) {
|
||
|
fd.ErrorCode = SSRESP_COMPRESSFAIL;
|
||
|
dprintf1(("Compress failure on %d for %s\n", ThreadId, fd.Path));
|
||
|
}
|
||
|
else bOK = TRUE;
|
||
|
} except(EXCEPTION_EXECUTE_HANDLER) {
|
||
|
if (!bOK){
|
||
|
fd.ErrorCode = SSRESP_COMPRESSEXCEPT;
|
||
|
dprintf1(("Compress failure on %d for %s\n", ThreadId, fd.Path));
|
||
|
#ifdef trace
|
||
|
{ char msg[80];
|
||
|
wsprintf( msg, "Compress failure on %d for %s\n"
|
||
|
, ThreadId, fd.Path);
|
||
|
Trace_File(msg);
|
||
|
}
|
||
|
#endif
|
||
|
}
|
||
|
}
|
||
|
|
||
|
}
|
||
|
|
||
|
//dprintf1(("%d Putting file '%s' onto Read Queue\n", ThreadId, fd.Path));
|
||
|
if (!Queue_Put(OutQueue, (LPBYTE)&fd, sizeof(fd))) {
|
||
|
dprintf1(("%d Put to ReadQueue failed for %s.\n", ThreadId, fd.Path));
|
||
|
Queue_Abort(Queue, NULL);
|
||
|
DeleteFile(fd.TempName);
|
||
|
|
||
|
Aborting = TRUE;
|
||
|
/* bug: If this Queue_Put fails on the very first Put,
|
||
|
then the next queue in the chain after OutQueue will
|
||
|
never come alive and so will never get Destroyed.
|
||
|
Worst it could cause is a memory leak. ???
|
||
|
*/
|
||
|
continue; /* next Queue_Get destroys Queue */
|
||
|
}
|
||
|
}
|
||
|
return 0;
|
||
|
} /* PackFile */
|
||
|
|
||
|
|
||
|
|
||
|
/* Use the file name in *fd and get its attributes (size, time etc)
|
||
|
Add these to fd. If it fails, set the ErrorCode in *fd
|
||
|
to an appropriate non-zero value.
|
||
|
*/
|
||
|
STATIC BOOL AddFileAttributes(FILEDETAILS * fd)
|
||
|
{
|
||
|
HANDLE hFile;
|
||
|
BY_HANDLE_FILE_INFORMATION bhfi;
|
||
|
|
||
|
hFile = CreateFile(fd->Path, GENERIC_READ, FILE_SHARE_READ,
|
||
|
NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
|
||
|
if (hFile == INVALID_HANDLE_VALUE) {
|
||
|
|
||
|
fd->ErrorCode = SSRESP_CANTOPEN;
|
||
|
return FALSE;
|
||
|
|
||
|
}
|
||
|
|
||
|
/* bug in GetFileInformationByHandle if file not on local
|
||
|
* machine? Avoid it!
|
||
|
*/
|
||
|
bhfi.dwFileAttributes = GetFileAttributes(fd->Path);
|
||
|
if (bhfi.dwFileAttributes == 0xFFFFFFFF) {
|
||
|
fd->ErrorCode = SSRESP_NOATTRIBS;
|
||
|
CloseHandle(hFile);
|
||
|
return FALSE;
|
||
|
}
|
||
|
|
||
|
if (!GetFileTime(hFile, &bhfi.ftCreationTime,
|
||
|
&bhfi.ftLastAccessTime, &bhfi.ftLastWriteTime)){
|
||
|
|
||
|
fd->ErrorCode = SSRESP_NOATTRIBS;
|
||
|
dprintf1(("Can't get file attributes for %s\n"
|
||
|
, (fd->Path?fd->Path : "NULL")));
|
||
|
CloseHandle(hFile);
|
||
|
return FALSE;
|
||
|
}
|
||
|
|
||
|
|
||
|
CloseHandle(hFile);
|
||
|
|
||
|
{
|
||
|
LONG err;
|
||
|
fd->Checksum = checksum_file(fd->Path, &err);
|
||
|
if (err!=0) {
|
||
|
fd->ErrorCode = SSRESP_CANTOPEN;
|
||
|
return FALSE;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
fd->ft_lastwrite = bhfi.ftLastWriteTime;
|
||
|
fd->ft_lastaccess = bhfi.ftLastAccessTime;
|
||
|
fd->ft_create = bhfi.ftCreationTime;
|
||
|
fd->SizeHi = bhfi.nFileSizeHigh;
|
||
|
fd->SizeLo = bhfi.nFileSizeLow;
|
||
|
fd->fileattribs = bhfi.dwFileAttributes;
|
||
|
return TRUE;
|
||
|
|
||
|
} /* AddFileAttributes */
|
||
|
|
||
|
|
||
|
/* Dequeue elements from Queue, Create on the output queue a SSNEWRESP
|
||
|
followed by 1 or more SSNEWPACK structures, the last of which will be
|
||
|
shorter than full length (zero length data if need be) to mark end-of-file.
|
||
|
Files with errors already get zero SSNEWPACKs but bad code in SSNEWRESP.
|
||
|
The output queue is the instance data of Queue.
|
||
|
*/
|
||
|
STATIC int ReadInFile(QUEUE Queue)
|
||
|
{ FILEDETAILS fd; /* The queue element processed */
|
||
|
QUEUE OutQueue;
|
||
|
HANDLE hFile; /* The packed file */
|
||
|
SSNEWPACK Pack; /* output message */
|
||
|
BOOL ShortBlockSent; /* no need to send another SSNEWPACK
|
||
|
Client knows the file has ended */
|
||
|
BOOL Aborting = FALSE; /* Input has been aborted. e.g. because output sick */
|
||
|
|
||
|
|
||
|
dprintf1(("File reader starting \n"));
|
||
|
OutQueue = (QUEUE)Queue_GetInstanceData(Queue);
|
||
|
for (; ; ) /* for each file */
|
||
|
{ int rc; /* return code from Queue_Get */
|
||
|
|
||
|
rc = Queue_Get(Queue, (LPBYTE)&fd, sizeof(fd));
|
||
|
if (rc==STOPTHREAD || rc==ENDQUEUE) {
|
||
|
if (!Aborting) {
|
||
|
/* Enqueue a No More Files response */
|
||
|
SSNEWRESP resp;
|
||
|
resp.lVersion = SS_VERSION;
|
||
|
resp.lResponse = LRESPONSE;
|
||
|
resp.lCode = SSRESP_END;
|
||
|
if (!Queue_Put( OutQueue, (LPBYTE)&resp , RESPHEADSIZE)) {
|
||
|
dprintf1(("Failed to Put SSRESP_END on SendQueue\n"));
|
||
|
}
|
||
|
//// dprintf1(( "Qued SSRESP_END: %x %x %x %x...\n"
|
||
|
//// , resp.lVersion, resp.lResponse, resp.lCode, resp.ulSize));
|
||
|
}
|
||
|
if (rc==ENDQUEUE)
|
||
|
Queue_Destroy(OutQueue);
|
||
|
dprintf1(("File reader ending\n"));
|
||
|
ExitThread(0);
|
||
|
}
|
||
|
else if (rc<0){
|
||
|
dprintf1(("ReadIn aborting. Bad return code %d from Queue_Get.\n", rc));
|
||
|
if (Aborting) break; /* All gone wrong. Just quit! */
|
||
|
Queue_Abort(Queue, PurgePackedFiles);
|
||
|
CloseHandle(hFile);
|
||
|
Aborting = TRUE;
|
||
|
continue; /* next Get gets STOPTHREAD */
|
||
|
}
|
||
|
|
||
|
//dprintf1(( "Reading file '%s' Error code %d\n"
|
||
|
// , (fd.TempName?fd.TempName:"NULL"), fd.ErrorCode
|
||
|
// ));
|
||
|
|
||
|
if (fd.ErrorCode==0) {
|
||
|
/* open temp (compressed) file */
|
||
|
hFile = CreateFile(fd.TempName, GENERIC_READ, 0, NULL,
|
||
|
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
|
||
|
if (hFile == INVALID_HANDLE_VALUE) {
|
||
|
/* report that we could not read the file */
|
||
|
fd.ErrorCode = SSRESP_NOREADCOMP;
|
||
|
dprintf1(( "Couldn't open compressed file for %s %s\n"
|
||
|
, fd.Path, fd.TempName));
|
||
|
}
|
||
|
}
|
||
|
if ( fd.ErrorCode==SSRESP_COMPRESSFAIL
|
||
|
|| fd.ErrorCode==SSRESP_NOREADCOMP
|
||
|
|| fd.ErrorCode==SSRESP_NOTEMPPATH
|
||
|
|| fd.ErrorCode==SSRESP_COMPRESSEXCEPT
|
||
|
) {
|
||
|
/* open original uncompressed file */
|
||
|
hFile = CreateFile(fd.Path, GENERIC_READ, 0, NULL,
|
||
|
OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
|
||
|
if (hFile == INVALID_HANDLE_VALUE) {
|
||
|
/* report that we could not read the file */
|
||
|
fd.ErrorCode = SSRESP_NOREAD;
|
||
|
dprintf1(( "Couldn't open file %s \n", fd.Path));
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Put the file name etc on the output queue as a SSNEWRESP */
|
||
|
{ SSNEWRESP resp;
|
||
|
LPSTR LocalName;
|
||
|
resp.lVersion = SS_VERSION;
|
||
|
resp.lResponse = LRESPONSE;
|
||
|
resp.lCode = (fd.ErrorCode ? fd.ErrorCode: SSRESP_FILE);
|
||
|
resp.ulSize = fd.SizeLo; /* file size <= 4GB !!! */
|
||
|
resp.fileattribs = fd.fileattribs;
|
||
|
resp.ft_create = fd.ft_create;
|
||
|
resp.ft_lastwrite = fd.ft_lastwrite;
|
||
|
resp.ft_lastaccess = fd.ft_lastaccess;
|
||
|
resp.ulSum = fd.Checksum;
|
||
|
resp.bSumValid = FALSE;
|
||
|
strcpy(resp.szFile, fd.Path);
|
||
|
LocalName = resp.szFile+strlen(resp.szFile)+1;
|
||
|
strcpy(LocalName, fd.LocalName);
|
||
|
|
||
|
if(!Queue_Put( OutQueue, (LPBYTE)&resp
|
||
|
, RESPHEADSIZE + strlen(resp.szFile)
|
||
|
+strlen(LocalName)+2)
|
||
|
) {
|
||
|
dprintf1(("Put to SendQueue failed.\n"));
|
||
|
Queue_Abort(Queue, PurgePackedFiles);
|
||
|
Aborting = TRUE;
|
||
|
CloseHandle(hFile);
|
||
|
continue; /* next Get gets STOPTHREAD */
|
||
|
}
|
||
|
// dprintf1(( "Qued SSRESP_FILE: %x %x %x %x...\n"
|
||
|
// , resp.lVersion, resp.lResponse, resp.lCode, resp.ulSize));
|
||
|
}
|
||
|
|
||
|
Pack.lSequence = 0;
|
||
|
/* Loop reading blocks of the file and queueing them
|
||
|
Set fd.ErrorCode for failures.
|
||
|
|
||
|
I'm worried about file systems that give me short blocks in the
|
||
|
middles of files!!!
|
||
|
*/
|
||
|
ShortBlockSent = FALSE;
|
||
|
if ( fd.ErrorCode==SSRESP_COMPRESSFAIL
|
||
|
|| fd.ErrorCode==SSRESP_NOREADCOMP
|
||
|
|| fd.ErrorCode==SSRESP_NOTEMPPATH
|
||
|
|| fd.ErrorCode==SSRESP_COMPRESSEXCEPT
|
||
|
|| fd.ErrorCode==0
|
||
|
) {
|
||
|
for(;;) /* for each block */
|
||
|
{
|
||
|
DWORD ActSize; /* bytes read */
|
||
|
|
||
|
if( !ReadFile( hFile, &(Pack.Data), sizeof(Pack.Data)
|
||
|
, &ActSize, NULL) ) {
|
||
|
/* error reading temp file. */
|
||
|
if (ShortBlockSent) {
|
||
|
/* Fine. End reached */
|
||
|
/* Should check error was end of file !!! */
|
||
|
CloseHandle(hFile);
|
||
|
break; /* blocks loop */
|
||
|
}
|
||
|
dprintf1(( "Error reading temp file %s.\n"
|
||
|
, (fd.TempName?fd.TempName:"NULL")));
|
||
|
CloseHandle(hFile);
|
||
|
dprintf1(("deleting bad file: %s\n", fd.TempName));
|
||
|
DeleteFile(fd.TempName);
|
||
|
Pack.ulSize = (ULONG)(-2); /* tell client */
|
||
|
break; /* blocks loop */
|
||
|
}
|
||
|
else if (ActSize > sizeof(Pack.Data)) {
|
||
|
dprintf1(( "!!? Read too long! %d %d\n"
|
||
|
, ActSize, sizeof(Pack.Data)));
|
||
|
Pack.ulSize = (ULONG)(-1); /* tell client */
|
||
|
}
|
||
|
else Pack.ulSize = ActSize;
|
||
|
|
||
|
if (ActSize==0 && ShortBlockSent) {
|
||
|
/* This is normal! */
|
||
|
CloseHandle(hFile);
|
||
|
break;
|
||
|
}
|
||
|
else ++Pack.lSequence;
|
||
|
|
||
|
|
||
|
Pack.lPacket = LPACKET;
|
||
|
Pack.lVersion = SS_VERSION;
|
||
|
Pack.ulSum = 0;
|
||
|
//////////////////// Pack.ulSum = ss_checksum_block(Pack.Data, ActSize); ///////////
|
||
|
if(!Queue_Put( OutQueue, (LPBYTE)&Pack
|
||
|
, PACKHEADSIZE+ActSize)){
|
||
|
dprintf1(("Put to SendQueue failed.\n"));
|
||
|
Queue_Abort(Queue, PurgePackedFiles);
|
||
|
CloseHandle(hFile);
|
||
|
Aborting = TRUE;
|
||
|
break; /* from blocks loop */
|
||
|
}
|
||
|
// dprintf1(( "Qued SSNEWPACK: %x %x %x %x %x...\n"
|
||
|
// , Pack.lVersion, Pack.lPacket, Pack.lSequence, Pack.ulSize
|
||
|
// , Pack.ulSum));
|
||
|
|
||
|
if (ActSize<PACKDATALENGTH) { /* Success. Finished */
|
||
|
ShortBlockSent = TRUE;
|
||
|
}
|
||
|
|
||
|
}
|
||
|
} /* blocks */
|
||
|
|
||
|
/* The data is all in storage now. Delete the temp file
|
||
|
If there was no temp file (due to error) this still should be harmless.
|
||
|
*/
|
||
|
#ifndef LAURIE
|
||
|
DeleteFile(fd.TempName);
|
||
|
#endif // LAURIE
|
||
|
// dprintf1(("deleting file: %s\n", fd.TempName));
|
||
|
|
||
|
} /* files */
|
||
|
|
||
|
return 0;
|
||
|
} /* ReadInFile */
|
||
|
|
||
|
|
||
|
/* Dequeue elements from Queue, send them down the pipe whose
|
||
|
handle is the instance data of Queue.
|
||
|
On error Abort Queue.
|
||
|
*/
|
||
|
STATIC int SendData(QUEUE Queue)
|
||
|
{
|
||
|
SSNEWPACK ssp; /* relies on this being no shorter than a SSRESP */
|
||
|
#ifdef SOCKETS
|
||
|
SOCKET OutPipe;
|
||
|
#else
|
||
|
HANDLE OutPipe;
|
||
|
#endif /* SOCKETS */
|
||
|
|
||
|
BOOL Aborting = FALSE; /* TRUE means input has been aborted */
|
||
|
|
||
|
dprintf1(("File sender starting \n"));
|
||
|
if (!SetThreadPriority(GetCurrentThread(),THREAD_PRIORITY_HIGHEST))
|
||
|
dprintf1(("Failed to set thread priority\n"));
|
||
|
|
||
|
#ifdef SOCKETS
|
||
|
OutPipe = (SOCKET)Queue_GetInstanceData(Queue);
|
||
|
#else
|
||
|
OutPipe = (HANDLE)Queue_GetInstanceData(Queue);
|
||
|
#endif
|
||
|
try{
|
||
|
for (; ; ) {
|
||
|
int rc; /* return code of Queue_Get */
|
||
|
|
||
|
rc = Queue_Get(Queue, (LPBYTE)&ssp, sizeof(ssp));
|
||
|
if (rc==STOPTHREAD || rc==ENDQUEUE)
|
||
|
{
|
||
|
break;
|
||
|
}
|
||
|
else if (rc<0) {
|
||
|
dprintf1(("Send thread aborting. Bad rc %d from Get_Queue.\n", rc));
|
||
|
if (Aborting) break; /* All gone wrong. Just quit! */
|
||
|
Queue_Abort(Queue, NULL);
|
||
|
Aborting = TRUE;
|
||
|
continue; /* next Queue_Get destroys Queue */
|
||
|
}
|
||
|
|
||
|
// // { ULONG Sum;
|
||
|
// // if (ssp.lPacket==LPACKET) {
|
||
|
// // if (ssp.ulSum != (Sum =ss_checksum_block(ssp.Data, ssp.ulSize))) {
|
||
|
// // dprintf1(( "!!Checksum error at send. Was %x should be %x\n"
|
||
|
// // , Sum, ssp.ulSum));
|
||
|
// // }
|
||
|
// // }
|
||
|
// // }
|
||
|
|
||
|
#ifdef SOCKETS
|
||
|
if(SOCKET_ERROR != send(OutPipe, (char far *)&ssp, ssp.ulSize+PACKHEADSIZE, 0) )
|
||
|
|
||
|
#else
|
||
|
if (!ss_sendblock(OutPipe, (PSTR) &ssp, rc))
|
||
|
#endif /* SOCKETS */
|
||
|
{
|
||
|
dprintf1(("Connection on pipe %x lost during send\n", OutPipe));
|
||
|
Queue_Abort(Queue, NULL);
|
||
|
Aborting = TRUE;
|
||
|
continue; /* next Queue_Get destroys Queue */
|
||
|
|
||
|
}
|
||
|
////dprintf1(( "Sent %x %x %x %x %x...\n"
|
||
|
//// , ssp.lVersion, ssp.lPacket, ssp.lSequence, ssp.ulSize, ssp.ulSum));
|
||
|
} /* packets */
|
||
|
}
|
||
|
finally{
|
||
|
/* kill the data pipe cleanly */
|
||
|
#ifndef SOCKETS
|
||
|
FlushFileBuffers(OutPipe);
|
||
|
DisconnectNamedPipe(OutPipe);
|
||
|
#endif /* NOT SOCKETS */
|
||
|
CLOSEHANDLE(OutPipe);
|
||
|
dprintf1(("Data send thread ending.\n"));
|
||
|
}
|
||
|
|
||
|
return 0; /* exit thread */
|
||
|
} /* SendData */
|
||
|
|
||
|
|
||
|
/* This gets called once for every FILEDETAILS on the ReadInQueue
|
||
|
to delete the temp files.
|
||
|
*/
|
||
|
STATIC void PurgePackedFiles(PSTR Ptr, int Len)
|
||
|
{ FILEDETAILS * pfd;
|
||
|
|
||
|
pfd = (FILEDETAILS *)Ptr;
|
||
|
// dprintf1(("purging file: %s\n", pfd->TempName));
|
||
|
DeleteFile(pfd->TempName);
|
||
|
|
||
|
} /* PurgePackedFiles */
|
||
|
|
||
|
#if 0
|
||
|
/* produce a checksum of a block of data.
|
||
|
*
|
||
|
* This is undoubtedly a good checksum algorithm, but it's also compute bound.
|
||
|
* For version 1 we turn it off. If we decide in version 2 to turn it back
|
||
|
* on again then we will use a faster algorithm (e.g. the one used to checksum
|
||
|
* a whole file.
|
||
|
*
|
||
|
* Generate checksum by the formula
|
||
|
* checksum = SUM( rnd(i)*(1+byte[i]) )
|
||
|
* where byte[i] is the i-th byte in the file, counting from 1
|
||
|
* rnd(x) is a pseudo-random number generated from the seed x.
|
||
|
*
|
||
|
* Adding 1 to byte ensures that all null bytes contribute, rather than
|
||
|
* being ignored. Multiplying each such byte by a pseudo-random
|
||
|
* function of its position ensures that "anagrams" of each other come
|
||
|
* to different sums. The pseudorandom function chosen is successive
|
||
|
* powers of 1664525 modulo 2**32. 1664525 is a magic number taken
|
||
|
* from Donald Knuth's "The Art Of Computer Programming"
|
||
|
*/
|
||
|
|
||
|
ULONG
|
||
|
ss_checksum_block(PSTR block, int size)
|
||
|
{
|
||
|
unsigned long lCheckSum = 0; /* grows into the checksum */
|
||
|
const unsigned long lSeed = 1664525; /* seed for random Knuth */
|
||
|
unsigned long lRand = 1; /* seed**n */
|
||
|
unsigned long lIndex = 1; /* byte number in block */
|
||
|
unsigned Byte; /* next byte to process in buffer */
|
||
|
unsigned length; /* unsigned copy of size */
|
||
|
|
||
|
length = size;
|
||
|
for (Byte = 0; Byte < length ;++Byte, ++lIndex) {
|
||
|
|
||
|
lRand = lRand*lSeed;
|
||
|
lCheckSum += lIndex*(1+block[Byte])*lRand;
|
||
|
}
|
||
|
|
||
|
return(lCheckSum);
|
||
|
} /* ss_checksum_block */
|
||
|
#endif
|