Auto merge of #2070 - nielx:haiku-raw-pointers, r=JohnTitor

Haiku: use raw pointers instead of references in convenience functions

The Haiku API has some convenience macros to make it easier to call certain
functions. In the libc implementation, these are implemented as unsafe
functions. The previous choice was to take certain pointer parameters as
references, and do the conversion to raw pointers when the actual external
function was called.

However, this causes issues with the image_info struct, which needs to be
initialized in Rust, before a native API call is used to enter data. Since
part of this structure consists of function pointers, mem::zeroed() cannot be
used, since in Rust function pointers cannot be NULL. Thus one needs to use the
MaybeUnit<T> API to properly initialize it. This then makes it problematic to
use the convenience functions, as a MaybeUnit<image_info> cannot be converted
into an &mut image_info before it is marked as initialized with valid data. It can
be converted into a raw *mut image_info, so if the function accepts this as a
parameter it can be used.

For consistency, all convenience functions have been converted from using
references to using raw pointers.

Author: bors

src/unix/haiku/native.rs

@@ -1023,14 +1023,14 @@ pub unsafe fn get_next_area_info(
     )
 }
 
-pub unsafe fn get_port_info(port: port_id, buf: &mut port_info) -> status_t {
+pub unsafe fn get_port_info(port: port_id, buf: *mut port_info) -> status_t {
     _get_port_info(port, buf, core::mem::size_of::<port_info>() as ::size_t)
 }
 
 pub unsafe fn get_next_port_info(
     port: port_id,
-    cookie: &mut i32,
-    portInfo: &mut port_info,
+    cookie: *mut i32,
+    portInfo: *mut port_info,
 ) -> status_t {
     _get_next_port_info(
         port,
@@ -1042,7 +1042,7 @@ pub unsafe fn get_next_port_info(
 
 pub unsafe fn get_port_message_info_etc(
     port: port_id,
-    info: &mut port_message_info,
+    info: *mut port_message_info,
     flags: u32,
     timeout: bigtime_t,
 ) -> status_t {
@@ -1055,14 +1055,14 @@ pub unsafe fn get_port_message_info_etc(
     )
 }
 
-pub unsafe fn get_sem_info(id: sem_id, info: &mut sem_info) -> status_t {
+pub unsafe fn get_sem_info(id: sem_id, info: *mut sem_info) -> status_t {
     _get_sem_info(id, info, core::mem::size_of::<sem_info>() as ::size_t)
 }
 
 pub unsafe fn get_next_sem_info(
     team: team_id,
-    cookie: &mut i32,
-    info: &mut sem_info,
+    cookie: *mut i32,
+    info: *mut sem_info,
 ) -> status_t {
     _get_next_sem_info(
         team,
@@ -1072,13 +1072,13 @@ pub unsafe fn get_next_sem_info(
     )
 }
 
-pub unsafe fn get_team_info(team: team_id, info: &mut team_info) -> status_t {
+pub unsafe fn get_team_info(team: team_id, info: *mut team_info) -> status_t {
     _get_team_info(team, info, core::mem::size_of::<team_info>() as ::size_t)
 }
 
 pub unsafe fn get_next_team_info(
-    cookie: &mut i32,
-    info: &mut team_info,
+    cookie: *mut i32,
+    info: *mut team_info,
 ) -> status_t {
     _get_next_team_info(
         cookie,
@@ -1090,7 +1090,7 @@ pub unsafe fn get_next_team_info(
 pub unsafe fn get_team_usage_info(
     team: team_id,
     who: i32,
-    info: &mut team_usage_info,
+    info: *mut team_usage_info,
 ) -> status_t {
     _get_team_usage_info(
         team,
@@ -1102,15 +1102,15 @@ pub unsafe fn get_team_usage_info(
 
 pub unsafe fn get_thread_info(
     id: thread_id,
-    info: &mut thread_info,
+    info: *mut thread_info,
 ) -> status_t {
     _get_thread_info(id, info, core::mem::size_of::<thread_info>() as ::size_t)
 }
 
 pub unsafe fn get_next_thread_info(
     team: team_id,
-    cookie: &mut i32,
-    info: &mut thread_info,
+    cookie: *mut i32,
+    info: *mut thread_info,
 ) -> status_t {
     _get_next_thread_info(
         team,
@@ -1123,7 +1123,7 @@ pub unsafe fn get_next_thread_info(
 // kernel/image.h
 pub unsafe fn get_image_info(
     image: image_id,
-    info: &mut image_info,
+    info: *mut image_info,
 ) -> status_t {
     _get_image_info(
         image,
@@ -1134,8 +1134,8 @@ pub unsafe fn get_image_info(
 
 pub unsafe fn get_next_image_info(
     team: team_id,
-    cookie: &mut i32,
-    info: &mut image_info,
+    cookie: *mut i32,
+    info: *mut image_info,
 ) -> status_t {
     _get_next_image_info(
         team,