Hi
I have a question to an string Array.
I enumerate processes and store the strings store it to an array "processname strings lenght is unknow"
must i before i strore this strings in a Array alloctate memory for it?
I think use i not alloctate memory overwrite it other entry in the data? section if not enough space or not?
example:
hArry db 20 dup(?)
hOtherHandle dd ?
Have this file more as 20bytes entry overwrite it my hOtherhandle
How i can get the enough size for Allocate the memory?
And can i make this with a struct?
Regards,
You can allocate more memory using GlobalAlloc (http://msdn.microsoft.com/en-us/library/aa366574%28v=vs.85%29.aspx). It will give you a handle of the new block of memory, so then you pass that to GlobalLock (http://msdn.microsoft.com/en-us/library/aa366584%28v=vs.85%29.aspx) to get the address (void*) of your newly allocated memory for free use. :U
here an quick & dirty exsample for an dynamic growing string array (pointer array):
Quoteinclude masm32rt.inc
.code
init_str_tbl proc
mov eax,alloc(4)
ret
init_str_tbl endp
add_str proc uses esi ebx ppsz: ptr PCHAR,psz: ptr CHAR
mov eax,ppsz
xor esi,esi
.while DWORD ptr [eax+esi]
lea esi,[esi+4]
.endw
mov ebx,rv(GlobalReAlloc,ppsz,ADDR [esi+8],GMEM_ZEROINIT or GMEM_MOVEABLE)
lea eax,[len(psz)+1]
mov DWORD ptr [ebx+esi],alloc(eax)
invoke szCopy,psz,eax
mov eax,ebx
ret
add_str endp
main proc
LOCAL ppsz: ptr PCHAR
mov ppsz,rv(init_str_tbl)
mov ppsz,rv(add_str,ppsz,input("string1: "))
mov ppsz,rv(add_str,ppsz,input("string2: "))
mov ppsz,rv(add_str,ppsz,input("string3: "))
; ppsz is an pointer to an pointer array
mov esi,ppsz
xor edi,edi
.while DWORD ptr [esi+edi*4]
print "string Nr. "
print str$(ADDR [edi+1])
print ": "
print PCHAR ptr [esi+edi*4],13,10
; free memory/string
; free PCHAR ptr [esi+edi*4]
lea edi,[edi+1]
.endw
; free ppsz
inkey
exit
main endp
end main
There are numerous options, depending how complicated you want to make it...
- allocate a large block of memory, and hope it's enough (max_process_name_length * max_num_processes)
- enumerate the process list in two passes; the first just sums the string lengths without saving them, then allocate the required memory, and the second pass can store the strings
- create an array of pointers, and allocate a new block of memory for each string, storing the pointer in the array
- allocate a large block, fill it up, and expand (realloc) if needed
- ...many others, mainly involving dynamic allocation...
it is likely that a large allocation will work - there are only so many processes running
but - the 2 pass method seems prettier :P
Thanks for your help
This array tips have i saveit i need it later :U
Why? I use now EnumProcess this have allready a pointer to an array :bg
Greets,
If speed is less critical than reliability, ease of use and scalability (which is almost always the case), you can use the DSA functions (http://msdn.microsoft.com/en-us/library/ff485930%28v=VS.85%29.aspx) from common controls
MAX_PROCESS_NAME equ 64 ; arbitrary value
PROCESS_NAME struct
PID DD ?
szName DB MAX_PROCESS_NAME DUP (?)
PROCESS_NAME ends
; Allocate a working structure
pronam PROCESS_NAME <>
; Create the array with 64 initial items
; it will grow by this number as needed
invoke DSA_Create, SIZEOF PROCESS_NAME, 64
mov hDSA, eax
; fill the working array with the data
mov eax, pid
mov pronam.PID, eax
invoke lstrcpyn, offset pronam.szName, offset TheProcessName, MAX_PROCESS_NAME-1
; Add an item
invoke DSA_InsertItem, hDSA, DSA_APPEND, offset pronam
; retrieve an item by item number (1). Fills pronam with the data
invoke DSA_GetItem, hDSA, 1, offset pronam