[WIP] Improve Windows support

Get interface information using IP Helper API

Cargo.toml

@@ -16,3 +16,6 @@ pnet_datalink = "0.28"
 
 [target.'cfg(windows)'.dependencies]
 winapi = { version = "0.3.9", features = [ "std" ] }
+[dependencies.windows]
+version = "0.29.0"
+features = ["Win32_Foundation","Win32_NetworkManagement_IpHelper"]

src/lib.rs

@@ -1,3 +1,4 @@
+mod os;
 pub mod interface;
 pub mod gateway;
 

src/os/mod.rs

@@ -0,0 +1,2 @@
+#[cfg(target_os = "windows")]
+pub mod windows;

src/os/windows.rs

@@ -0,0 +1,69 @@
+use windows::Win32::NetworkManagement::IpHelper::{GetAdaptersInfo, IP_ADAPTER_INFO, IP_ADDR_STRING};
+use std::convert::TryInto;
+use std::mem;
+
+pub const ERROR_BUFFER_OVERFLOW: u32 = 111;
+pub const NO_ERROR: u32 = 0;
+
+// Get network interface information using the IP Helper API
+// TODO: Make more rusty way...
+// Reference: https://docs.microsoft.com/en-us/windows/win32/api/iphlpapi/nf-iphlpapi-getadaptersinfo
+pub fn get_interfaces() {
+    let mut out_buf_len : u32 = mem::size_of::<IP_ADAPTER_INFO>().try_into().unwrap();
+    let mut raw_adaptor_mem: Vec<u8> = Vec::with_capacity(out_buf_len  as usize);
+    let mut p_adaptor: *mut IP_ADAPTER_INFO;
+    let mut res = unsafe { GetAdaptersInfo(raw_adaptor_mem.as_mut_ptr() as *mut IP_ADAPTER_INFO, &mut out_buf_len ) };
+    // Make an initial call to GetAdaptersInfo to get the necessary size into the out_buf_len variable
+    if res == ERROR_BUFFER_OVERFLOW {
+		raw_adaptor_mem = Vec::with_capacity(out_buf_len as usize);
+		unsafe {
+			res = GetAdaptersInfo(raw_adaptor_mem.as_mut_ptr() as *mut IP_ADAPTER_INFO, &mut out_buf_len);
+		}
+	}
+    if res != NO_ERROR {
+        //TODO
+		println!("failed to get adapters info");
+        // for test
+		std::process::exit(1);
+	}
+    //Enumerate all adapters
+	p_adaptor = unsafe { mem::transmute(&raw_adaptor_mem) };
+    while p_adaptor as u64 != 0 {
+        unsafe {
+			let adapter = *p_adaptor;
+            let adapter_name = String::from_utf8_lossy(&adapter.AdapterName);
+            let adapter_desc = String::from_utf8_lossy(&adapter.Description);
+            let mac_addr = adapter.Address.to_vec();
+            println!("{} {} {} {} {:?}", adapter.Index, adapter.ComboIndex, adapter_name, adapter_desc, mac_addr);
+            //Enumerate all IPs
+            let mut p_ip_addr: *mut IP_ADDR_STRING;
+            p_ip_addr = mem::transmute(&(*p_adaptor).IpAddressList);
+            while p_ip_addr as u64 != 0 {
+                let ip_addr_string = *p_ip_addr;
+                let ip_addr = String::from_utf8_lossy(&ip_addr_string.IpAddress.String);
+                println!("{}", ip_addr);
+                p_ip_addr = (*p_ip_addr).Next;
+            }
+            //Enumerate all gateways
+            let mut p_gateway_addr: *mut IP_ADDR_STRING;
+            p_gateway_addr = mem::transmute(&(*p_adaptor).GatewayList);
+            while p_gateway_addr as u64 != 0 {
+                let gateway_addr_string = *p_gateway_addr;
+                let gateway_addr = String::from_utf8_lossy(&gateway_addr_string.IpAddress.String);
+                println!("{}", gateway_addr);
+                p_gateway_addr = (*p_gateway_addr).Next;
+            }
+            //TODO
+		}
+        unsafe { p_adaptor = (*p_adaptor).Next; }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::os::windows;
+    #[test]
+    fn list_nw_interfaces() {
+        windows::get_interfaces();
+    }
+}