Re: win32api: how to access NetFileEnum results?

Trying to modify the below script to allow me to query remote
machines. The first parameter to NetFileEnum needs to be a char * to
the machine name. Can’t seem to work out how to do that in ruby.

Thanks,
RC

Subject: Re: win32api: how to access NetFileEnum results?
From: Jos B.
Date: Wed, 14 Jul 2004 09:28:13 +0900
References: 106163 106180 106240 106266
In-reply-to: 106266

–YiEDa0DAkWCtVeE4
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On Wed, Jul 14, 2004 at 04:57:21AM +0900, daz wrote:

Re-reading the API suggests a change of tack.
I think that memcpy isn’t required.
[snip]
p rbuf
#----------------------------------

Good or bad ?

This yields 10k worth of zeroes on my screen :slight_smile: I think I understand
what you
are trying to do (have win32api follow the pointer automagically) but I
can’t
seem to get it to work. bufptr does have the right value in this case
too, so
that part works fine, but I opted to use the simpler initialization
instead.
So I ended up doing some memcpy’s which I need anyway to access the
pathname
and username fields in the returned FILE_INFO_3 structs. The attached
code
works for me; cleanup suggestions welcomed!

Thanks for your help guys.

Cheers,

Jos B. / /// Sunnyvale, CA
_/ _/ _/
/ ///
_/ _/ _/ /
jos at catnook.com // //
/ require
‘std/disclaimer’

–YiEDa0DAkWCtVeE4
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#!/usr/bin/env ruby

LMSTR =

LPBYTE* = P

DWORD = L

LPDWORD = P

PDWORD_PTR = L

NET_API_STATUS NetFileEnum(

LMSTR servername,

LMSTR basepath,

LMSTR username,

DWORD level,

LPBYTE* bufptr,

DWORD prefmaxlen,

LPDWORD entriesread,

LPDWORD totalentries,

PDWORD_PTR resume_handle

#);

typedef struct _FILE_INFO_3 {

DWORD fi3_id;

DWORD fi3_permissions;

DWORD fi3_num_locks;

LMSTR fi3_pathname;

LMSTR fi3_username;

} FILE_INFO_3;

require “Win32API”

NetFileEnum = Win32API.new(‘netapi32’, ‘NetFileEnum’, ‘PPPNPNPPP’,‘I’)
Memcpy = Win32API.new(‘msvcrt’, ‘memcpy’, ‘PPL’, ‘P’)
Pmemcpy1 = Win32API.new(‘msvcrt’, ‘memcpy’, ‘PLL’, ‘L’)
Pmemcpy2 = Win32API.new(‘msvcrt’, ‘memcpy’, ‘LPL’, ‘L’)
Wcslen = Win32API.new(‘msvcrt’, ‘wcslen’, ‘P’, ‘L’)

class OpenFile
attr_reader :id, :permissions, :num_locks, :pathname, :username
def initialize(id, permissions, num_locks, p_pathname, p_username)
@id, @permissions, @num_locks = id, permissions, num_locks
pathlen = Wcslen.call(p_pathname) * 2
userlen = Wcslen.call(p_username) * 2
pname = “\0” * pathlen
uname = “\0” * userlen
Pmemcpy1.call(pname, p_pathname, pathlen)
Pmemcpy1.call(uname, p_username, userlen)
@pathname = pname.delete(“\0”)
@username = uname.delete(“\0”)
end
def inspect
“File #{@pathname} opened by #{@username} (id #{@id},
#{@num_locks} lock(s))”
end
end

MAX_PREFERRED_LENGTH = -1
FILE_INFO_3_SIZE = 20
LEVEL = 3

bufptr = “\0” * 4
entriesread = “\0” * 4
totalentries = “\0” * 4
resume_handle = “\0” * 4

ret = NetFileEnum.call(nil, nil, nil, LEVEL, bufptr,
MAX_PREFERRED_LENGTH,
entriesread, totalentries, resume_handle)

if 0 != ret
puts “Failed: #{ret}”
exit
end

entriesread = entriesread.unpack(“S”)[0]
totalentries = totalentries.unpack(“S”)[0]

rbuf = “\0” * entriesread * FILE_INFO_3_SIZE

bufptr now contains a ptr to a ptr

Pmemcpy1.call(rbuf, bufptr.unpack(“L”)[0], entriesread *
FILE_INFO_3_SIZE)

open_files = []
entriesread.times do |i|
open_files << OpenFile.new(*rbuf[i * FILE_INFO_3_SIZE, FILE_INFO_3_SIZE].unpack(“LLLLL”))
end

open_files.each do |file|
p file
end

exit