installer: test for more in-use files

The recently-added "blocked-file-util" is now being put to good use: we
enumerate the process IDs of the processes that use .exe or .dll files
from the installation location to skip the installation if the
/SKIPIFINUSE=1 option was specified.

This catches scenarios where users call non-Git executables directly
(e.g. C:\Program Files\Git\mingw64\bin\openssl.exe) and a silent
installation wants to just make sure that Git is installed.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

installer/install.iss

@@ -1502,9 +1502,29 @@ begin
 end;
 
 function ShouldSkipPage(PageID:Integer):Boolean;
+var
+    AppDir,Msg,Cmd,LogPath:String;
+    Res:Longint;
 begin
     if (ProcessesPage<>NIL) and (PageID=ProcessesPage.ID) then begin
         // This page is only reached forward (by pressing "Next", never by pressing "Back").
+        if (ParamIsSet('SKIPIFINUSE') or ParamIsSet('VSNOTICE')) then begin
+            AppDir:=ExpandConstant('{app}');
+            if DirExists(AppDir) then begin
+                if not FileExists(ExpandConstant('{tmp}\blocked-file-util.exe')) then
+                    ExtractTemporaryFile('blocked-file-util.exe');
+		LogPath:=ExpandConstant('{tmp}\blocking-pids.log');
+		Cmd:='/C ""'+ExpandConstant('{tmp}\blocked-file-util.exe')+'" blocking-pids "'+AppDir+'" 2>"'+LogPath+'""';
+                if not Exec(ExpandConstant('{sys}\cmd.exe'),Cmd,'',SW_HIDE,ewWaitUntilTerminated,Res) or (Res<>0) then begin
+                    Msg:='Skipping installation because '+AppDir+' is still in use:'+#13+#10+ReadFileAsString(LogPath);
+                    if ParamIsSet('SKIPIFINUSE') or (ExpandConstant('{log}')='') then
+                        LogError(Msg)
+                    else
+                        Log(Msg);
+                    ExitEarlyWithSuccess();
+                end;
+            end;
+        end;
         RefreshProcessList(NIL);
         Result:=(GetArrayLength(Processes)=0);
     end else begin

installer/release.sh

@@ -108,7 +108,8 @@ else
 	die "Could not generate file list"
 fi
 
-printf "; List of files\n%s\n%s\n%s\n%s\n%s\n" \
+printf '; List of files\n%s\n%s\n%s\n%s\n%s\n%s\n' \
+	"Source: \"mingw$BITNESS\\bin\\blocked-file-util.exe\"; Flags: dontcopy" \
 	"Source: \"{#SourcePath}\\package-versions.txt\"; DestDir: {app}\\etc; Flags: replacesameversion; AfterInstall: DeleteFromVirtualStore" \
 	"Source: \"{#SourcePath}\\..\\ReleaseNotes.css\"; DestDir: {app}\\usr\\share\\git; Flags: replacesameversion; AfterInstall: DeleteFromVirtualStore" \
 	"Source: \"cmd\\git.exe\"; DestDir: {app}\\bin; Flags: replacesameversion; AfterInstall: DeleteFromVirtualStore" \