idmap2: move Idmap.h to Result
Change the signatures of Idmap::FromApkAssets and
Idmap::FromBinaryStream from
std::unique_ptr<const Idmap> func(..., std::ostream& out_error);
to
Result<std::unique_ptr<const Idmap>> func(...);
The returned pointer is still a unique pointer to ensure the dynamically
allocated memory is automatically released when no longer used. This
means that using the returned value of either function requires one of
two patterns:
const auto idmap = func(...);
if (!idmap) {
return Error(...);
}
(*idmap)->accept(...);
or
auto result = func(...);
if (!result) {
return Error(...);
}
const auto idmap = std::move(*result);
idmap->accept(...);
Note that in the second example, result must be non-const or
the call to std::move(*result) will not compile.
With this change, the entire idmap2 project has been converted to use
Result.
Test: make idmap2_tests
Change-Id: I533f4e03b99645523d94dd5f446ad76fb435f661
diff --git a/cmds/idmap2/idmap2d/Idmap2Service.cpp b/cmds/idmap2/idmap2d/Idmap2Service.cpp
index e03a9cc..4f65379 100644
--- a/cmds/idmap2/idmap2d/Idmap2Service.cpp
+++ b/cmds/idmap2/idmap2d/Idmap2Service.cpp
@@ -138,12 +138,10 @@
return error("failed to load apk " + overlay_apk_path);
}
- std::stringstream err;
- const std::unique_ptr<const Idmap> idmap =
- Idmap::FromApkAssets(target_apk_path, *target_apk, overlay_apk_path, *overlay_apk,
- policy_bitmask, enforce_overlayable, err);
+ const auto idmap = Idmap::FromApkAssets(target_apk_path, *target_apk, overlay_apk_path,
+ *overlay_apk, policy_bitmask, enforce_overlayable);
if (!idmap) {
- return error(err.str());
+ return error(idmap.GetErrorMessage());
}
umask(kIdmapFilePermissionMask);
@@ -152,7 +150,7 @@
return error("failed to open idmap path " + idmap_path);
}
BinaryStreamVisitor visitor(fout);
- idmap->accept(&visitor);
+ (*idmap)->accept(&visitor);
fout.close();
if (fout.fail()) {
return error("failed to write to idmap path " + idmap_path);