1 files changed, 27 insertions, 5 deletions

diff --git a/src/libstore/builtins.cc b/src/libstore/builtins.cc
index 25e2e7df30e7..a1c4b48bf62e 100644
--- a/src/libstore/builtins.cc
+++ b/src/libstore/builtins.cc
@@ -1,5 +1,8 @@
 #include "builtins.hh"
 #include "download.hh"
+#include "store-api.hh"
+#include "archive.hh"
+#include "compression.hh"
 
 namespace nix {
 
@@ -7,17 +10,36 @@ void builtinFetchurl(const BasicDerivation & drv)
 {
     auto url = drv.env.find("url");
     if (url == drv.env.end()) throw Error("attribute ‘url’ missing");
-    printMsg(lvlInfo, format("downloading ‘%1%’...") % url->second);
-    auto data = downloadFile(url->second); // FIXME: show progress
+
+    /* No need to do TLS verification, because we check the hash of
+       the result anyway. */
+    DownloadOptions options;
+    options.verifyTLS = false;
+
+    /* Show a progress indicator, even though stderr is not a tty. */
+    options.forceProgress = true;
+
+    auto data = downloadFile(url->second, options);
 
     auto out = drv.env.find("out");
     if (out == drv.env.end()) throw Error("attribute ‘url’ missing");
-    writeFile(out->second, data.data);
+
+    Path storePath = out->second;
+    assertStorePath(storePath);
+
+    auto unpack = drv.env.find("unpack");
+    if (unpack != drv.env.end() && unpack->second == "1") {
+        if (string(data.data, 0, 6) == string("\xfd" "7zXZ\0", 6))
+            data.data = decompressXZ(data.data);
+        StringSource source(data.data);
+        restorePath(storePath, source);
+    } else
+        writeFile(storePath, data.data);
 
     auto executable = drv.env.find("executable");
     if (executable != drv.env.end() && executable->second == "1") {
-        if (chmod(out->second.c_str(), 0755) == -1)
-            throw SysError(format("making ‘%1%’ executable") % out->second);
+        if (chmod(storePath.c_str(), 0755) == -1)
+            throw SysError(format("making ‘%1%’ executable") % storePath);
     }
 }