Use powershell command for download

REQUIRE

@@ -1,5 +1,5 @@
 julia 0.6
-Compat 0.42.0
+Compat 0.56.0
 URIParser 0.0.3
 @unix HTTPClient 0.0.0
 LibExpat 0.2.8

src/WinRPM.jl

@@ -53,22 +53,24 @@ if isunix()
     end
 elseif iswindows()
     function download(source::AbstractString; retry=5)
-        dest = Vector{UInt16}(261)
+        ps = "C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe"
+        tls12 = "[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12"
+        client = "New-Object System.Net.Webclient"
+        # in the following we escape ' with '' (see https://ss64.com/ps/syntax-esc.html)
+        filename = joinpath(tempdir(), split(source, "/")[end])
+        downloadfile = "($client).DownloadFile('$(replace(source, "'" => "''"))', '$(replace(filename, "'" => "''"))')"
         for i in 1:retry
-            res = ccall((:URLDownloadToCacheFileW, :urlmon), stdcall, Cuint,
-              (Ptr{Void}, Ptr{UInt16}, Ptr{UInt16}, Clong, Cint, Ptr{Void}),
-              C_NULL, transcode(UInt16, source), dest, sizeof(dest) >> 1, 0, C_NULL)
-            if res == 0
-                resize!(dest, findfirst(iszero, dest) - 1)
-                filename = transcode(String, dest)
+            try
+                run(`$ps -NoProfile -Command "$tls12; $downloadfile"`)
                 if isfile(filename)
-                    return read(filename, String), 200
+                    return readstring(filename), 200
                 end
-            else
-                warn("Unknown download failure, error code: $res")
+            catch ex
+                warn("Unknown download failure. Retry $i/$retry downloading: $source")
             end
-            warn("Retry $i/$retry downloading: $source")
         end
+        warn("""Unknown download failure. WinRPM download function relies on Windows PowerShell functionality.
+            Check that PowerShell 3 or higher is installed and TLS 1.2 protocol support enabled.)""")
         return "", 0
     end
 else