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Here is my problem. Say I am sending a file via winsock. I select the file I want to share with my friend. Then how do i put the file i've selected into a buffer? The file data i mean. Once i send the buffer(file data) across to the recieving client, i can use the WriteFile API to "put it back together"-(ie. add in the filename/size etc.) This is what i'm aiming for...


invoke send,hSocket,addr FileData2BeSent_Buffer,eax,NULL

Anyone know? Sorry if this doesn't make much sense. I am at work and have had quite a bit of caffeine.:eek: heheheh Nok.

Posted on 2001-05-03 15:26:00 by Nokturnal

File data to a Buffer?

Hi Nokturnal, First of all sorry in case I misinterpreted your question *g* But I think you want to load the whole file into memory right? In this case you can use this code:


.data?
hMemory DWORD ?
pMemory DWORD ? ;pointing at the first byte in the buffer

     invoke GlobalAlloc,GHND,*the size required*
     mov hMemory,eax
     invoke GlobalLock,eax
     mov pMemory,eax
     ;load file into buffer
     ;...use the bytes of the file here
     invoke GlobalUnlock,pMemory
     invoke GlobalFree,hMemory

Personally I use a macro for this... I give you a quick example ;my own .inc file


AllocMem MACRO howbig
     invoke GlobalAlloc,GHND,howbig
     mov hMemory,eax
     invoke GlobalLock,eax
     mov pMemory,eax
ENDM
DeAllocMem MACRO
     invoke GlobalUnlock,pMemory
     invoke GlobalFree,hMemory
ENDM

;the code file


.data
FileName db "whatever.txt"
.data?
hMemory DWORD ?
pMemory DWORD ? ;pointing at the first byte in the buffer
hFile DWORD ?
filesize DWORD ?
NumberOfBytes DWORD ?

.code
;and you can use it easily like this then
invoke CreateFile,ADDR FileName,GENERIC_READ,0,0,\
                  OPEN_EXISTING,FILE_ATTRIBUTE_ARCHIVE
mov hFile,eax ;now we got your file's handle
invoke GetFileSize,hFile,0
mov filesize,eax
AllocMem eax
invoke ReadFile,hFile,pMemory,filesize,ADDR NumberOfBytes,0
.WHILE filesize!=0
  .IF filesize<=500
    invoke send,hsock,pMemory,filesize,NULL
    .BREAK
  .ENDIF
  invoke send,hsock,pMemory,500,NULL
  ;we send 500 bytes of it away
  sub filesize,500
  add pMemory,500
.ENDW
DeAllocMem
invoke CloseHandle,hFile

Well, I give no garantie that this is working code... you just need to split up your file into pieces as you can's send a complete Buffer of 2-3MB on the socket right away.. :) Hope this helps a little bit... I think Thomas gives away his source from his HTTP send/receive client a few threads below... be sure to check this out because I believe this is exactly what you're looking for ;) This message was edited by JimmyClif, on 5/3/2001 4:45:20 PM

Posted on 2001-05-03 16:22:00 by JimmyClif

File data to a Buffer?

My http file transfer program shows you how to load a file in memory: Take a look at this topic. Although this isn't a good method for large files (a 20mb file takes 20mb memory). Have a look at the program itself, too. Thomas This message was edited by Thomas, on 5/3/2001 4:24:13 PM

Posted on 2001-05-03 16:23:00 by Thomas

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