repo: Add ostree_repo_write_regfile

This API is push rather than pull, which makes it much more
suitable to use cases like parsing a tar file from external
code.

Now, we have a large mess in this area internally because
the original file writing code was pull based, but static
deltas hit the same problem of wanting a push API, so I added
this special `OstreeRepoBareContent` just for writing regular
files from a push API.

Eventually...I'd like to deprecate the pull based API,
and rework things so that for regular files the push API
is the default, and then `write_content_object()` would
be split up into archive/bare cases.

In this world the `ostree_repo_write_content()` API would
then need to hackily bridge pull to push and it'd be
less efficient.

Anyways for now due to this bifurcation, this API only
works on non-archive repositories, but that's fine for
now because that's what I want for the `ostree-ext-container`
bits.

tests/test-core.js

@@ -27,6 +27,22 @@ function assertEquals(a, b) {
 	throw new Error("assertion failed " + JSON.stringify(a) + " == " + JSON.stringify(b));
 }
 
+function assertThrows(s, f) {
+  let success = false;
+  try {
+    f();
+    success = true;
+  } catch(e) {
+    let msg = e.toString();
+    if (msg.indexOf(s) == -1) {
+      throw new Error("Error message didn't match '" + s + "': " + msg)    
+    }
+  }
+  if (success) {
+    throw new Error("Function was expected to throw, but didn't")
+  }
+}
+
 print('1..1')
 
 let testDataDir = Gio.File.new_for_path('test-data');
@@ -51,18 +67,14 @@ print("commit => " + commit);
 
 // Test direct write APIs
 let inline_content = "default 0.0.0.0\nloopback 127.0.0.0\nlink-local 169.254.0.0\n";
+let networks_checksum = "8aaa9dc13a0c5839fe4a277756798c609c53fac6fa2290314ecfef9041065873";
 let regfile_mode = 33188; // 0o100000 | 0o644 (but in decimal so old gjs works)
 let inline_checksum = repo.write_regfile_inline(null, 0, 0, regfile_mode, null, inline_content, null);
 assertEquals(inline_checksum, "8aaa9dc13a0c5839fe4a277756798c609c53fac6fa2290314ecfef9041065873");
-let written = false;
-try {
+assertThrows("Corrupted file object", function() {
     // Changed an a to b from above to make the checksum not match
     repo.write_regfile_inline("8baa9dc13a0c5839fe4a277756798c609c53fac6fa2290314ecfef9041065873", 0, 0, regfile_mode, null, inline_content, null);
-    written = true;
-} catch (e) {
-}
-if (written)
-  throw new Error("Wrote invalid checksum");
+});
 
 repo.commit_transaction(null, null);
 
@@ -85,4 +97,21 @@ repo.commit_transaction(null, null);
 [,readCommit] = repo.resolve_rev('someref', true);
 assertEquals(readCommit, null);
 
+// Test direct write API for regular files
+let clen = inline_content.length;
+assertThrows("Cannot currently use", function() {  
+  let w = repo.write_regfile(null, 0, 0, regfile_mode, clen, null);
+});
+
+let bareRepoPath = Gio.File.new_for_path('repo');
+let repo_bareu = OSTree.Repo.new(Gio.File.new_for_path('repo-bare'));
+repo_bareu.create(OSTree.RepoMode.BARE_USER_ONLY, null);
+let w = repo_bareu.write_regfile(null, 0, 0, regfile_mode, clen, null);
+// Test multiple write() calls
+w.write(inline_content.slice(0, 4), null)
+w.write(inline_content.slice(4, 10), null)
+w.write(inline_content.slice(10), null)
+let actual_checksum = w.finish(null)
+assertEquals(actual_checksum, networks_checksum)
+
 print("ok test-core");

tests/test-repo.c

@@ -241,7 +241,6 @@ test_write_regfile_api (Fixture *fixture,
   g_clear_pointer (&xattrs, g_variant_unref);
   g_variant_builder_init (&xattrs_builder, (GVariantType*)"a(ayay)");
   g_variant_builder_add (&xattrs_builder, "(^ay^ay)", "security.selinux", "system_u:object_r:bin_t:s0");
-  g_clear_pointer (&xattrs, g_variant_unref);
   xattrs = g_variant_ref_sink (g_variant_builder_end (&xattrs_builder));
 
   g_clear_pointer (&checksum, g_free);