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我的单元在64位运行时测试了这段代码的崩溃。Marshal.PtrToStructure在64位崩溃
在第二次循环迭代时,崩溃发生在Marshal.PtrToStructure调用上。 “entriesRead”说4,所以它应该能够正确读取,但它不会。 Marshal.SizeOf(typeof(WinAPI.NETAPI32.USER_INFO_4))在64位中为192个字节。这是错误的来源吗?
....
try {
int entriesRead;
int totalEntries;
int resumeHandle;
var result = WinAPI.NETAPI32.NetUserEnum(
this.NTCompatibleHostName,
3,
2,
out bufPtr,
-1,
out entriesRead,
out totalEntries,
out resumeHandle
);
if (result != 0) {
throw new NetApiException(
result,
"Failed to enumerate local users on host '{0}'",
Host
);
}
var structSize = Marshal.SizeOf(typeof(WinAPI.NETAPI32.USER_INFO_4));
var startAddr = bufPtr.ToInt64();
var endAddr = startAddr + entriesRead * structSize;
for (var offset = startAddr; offset < endAddr; offset += structSize) {
var userInfo =
(WinAPI.NETAPI32.USER_INFO_4)Marshal.PtrToStructure(
new IntPtr(offset),
typeof(WinAPI.NETAPI32.USER_INFO_4)
);
}
} catch (Exception error) {
}
[StructLayout(LayoutKind.Sequential)]
public struct USER_INFO_4 {
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_name;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_password;
public uint usri4_password_age;
public uint usri4_priv;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_home_dir;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_comment;
public uint usri4_flags;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_script_path;
public uint usri4_auth_flags;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_full_name;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_usr_comment;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_parms;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_workstations;
public uint usri4_last_logon;
public uint usri4_last_logoff;
public uint usri4_acct_expires;
public uint usri4_max_storage;
public uint usri4_units_per_week;
public IntPtr usri4_logon_hours;
public uint usri4_bad_pw_count;
public uint usri4_num_logons;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_logon_server;
public uint usri4_country_code;
public uint usri4_code_page;
public IntPtr usri4_user_sid;
public uint usri4_primary_group_id;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_profile;
[MarshalAs(UnmanagedType.LPWStr)]
public string usri4_home_dir_drive;
public uint usri4_password_expired;
}
[DllImport("netapi32.dll")]
[return: MarshalAs(UnmanagedType.U4)]
public static extern NET_API_STATUS NetUserEnum([MarshalAs(UnmanagedType.LPWStr)] string servername, int level, int filter, out IntPtr bufptr, int prefmaxlen, out int entriesread, out int totalentries, out int resume_handle);
令人惊讶的是,这显然在x86上工作了很多年。也许是一个随机崩溃的来源。我最终实现了184字节的USER_INFO_3结构。 – 2015-03-05 23:25:45