From d332f19e22bf5d6a31d5311d9228de631161e2a9 Mon Sep 17 00:00:00 2001
From: Alejandro R Mosteo <alejandro@mosteo.com>
Date: Tue, 2 Feb 2021 19:17:51 +0100
Subject: [PATCH] Fix problem with temporaries in Windows (#674)

* Attempt fix at windows temporaries

* Remove now superfluous exception handler

* Review fix
---
 src/alire/alire-directories.adb       | 30 ++++++++++++++-------------
 src/alire/alire-platform.ads          | 21 ++++++++++++++++++-
 src/alire/os_linux/alire-platform.adb |  1 +
 3 files changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/alire/alire-directories.adb b/src/alire/alire-directories.adb
index ced67f2b..238afdfa 100644
--- a/src/alire/alire-directories.adb
+++ b/src/alire/alire-directories.adb
@@ -3,6 +3,8 @@ with Ada.Numerics.Discrete_Random;
 with Ada.Text_IO;
 with Ada.Unchecked_Deallocation;
 
+with Alire.OS_Lib.Subprocess;
+with Alire.Platform;
 with Alire.Properties;
 with Alire.Roots;
 
@@ -349,6 +351,20 @@ package body Alire.Directories is
          return;
       end if;
 
+      --  Force writability of folder when in Windows, as some tools (e.g. git)
+      --  that create read-only files will cause a Use_Error
+
+      if Kind (This.Filename) = Directory and then Platform.On_Windows then
+         Trace.Debug ("Forcing writability of temporary dir " & This.Filename);
+         OS_Lib.Subprocess.Checked_Spawn
+           ("attrib",
+            Utils.Empty_Vector
+            .Append ("-R") -- Remove read-only
+            .Append ("/D") -- On dirs
+            .Append ("/S") -- Recursively
+            .Append (This.Filename & "\*"));
+      end if;
+
       if Exists (This.Filename) then
          if Kind (This.Filename) = Ordinary_File then
             Trace.Debug ("Deleting temporary file " & This.Filename & "...");
@@ -359,20 +375,6 @@ package body Alire.Directories is
          end if;
       end if;
    exception
-      when E : Use_Error =>
-         --  For unclear reasons, Windows has trouble removing a folder that
-         --  contains a git repository. Warn and continue until we know more.
-
-         --  The actual error, as reported by Python3:
-         --  PermissionError: [WinError 5] Access is denied:
-         --  'alr-fwrt.tmp\\.git\\objects\\1d\\'
-         --  '696bed4ef917b1adbdef18723016987ed62e41'
-
-         --  Since we are running tests as root, this might be that the file is
-         --  still open, but by whom?
-
-         Log_Exception (E);
-         Trace.Warning ("Could not delete temporary: " & This.Filename);
       when E : others =>
          Log_Exception (E);
          raise;
diff --git a/src/alire/alire-platform.ads b/src/alire/alire-platform.ads
index 3390ce4d..c476381b 100644
--- a/src/alire/alire-platform.ads
+++ b/src/alire/alire-platform.ads
@@ -1,6 +1,8 @@
 with Alire.Platforms;
 with Alire.Environment;
 
+private with GNATCOLL.OS.Constants;
+
 package Alire.Platform is
 
    --  Alr.Platforms will be progressively migrated in here as needed.
@@ -34,13 +36,30 @@ package Alire.Platform is
    --  via config.
 
    function Distribution_Is_Known return Boolean is
-      (Platforms."/=" (Distribution, Platforms.Distro_Unknown));
+     (Platforms."/=" (Distribution, Platforms.Distro_Unknown));
+
+   function On_Windows return Boolean;
+   --  Say if we are on Windows, until the OS detection is moved here from
+   --  Alr.Platform.
 
 private
 
+   ------------------
+   -- Distribution --
+   ------------------
+
    function Distribution return Platforms.Distributions
    is (if Disable_Distribution_Detection
        then Platforms.Distro_Unknown
        else Detected_Distribution);
 
+   ----------------
+   -- On_Windows --
+   ----------------
+
+   pragma Warnings (Off, "condition is always"); -- Silence warning of OS check
+   function On_Windows return Boolean
+   is (GNATCOLL.OS.Constants.OS in GNATCOLL.OS.Windows);
+   pragma Warnings (On);
+
 end Alire.Platform;
diff --git a/src/alire/os_linux/alire-platform.adb b/src/alire/os_linux/alire-platform.adb
index 360eb5e6..065565f3 100644
--- a/src/alire/os_linux/alire-platform.adb
+++ b/src/alire/os_linux/alire-platform.adb
@@ -1,5 +1,6 @@
 with Alire.OS_Lib.Subprocess;
 with Alire.Utils;
+
 with GNAT.Regpat;
 
 package body Alire.Platform is
-- 
2.39.5