Move build.prop to ./etc subdir for some partitions
build.prop files under system_ext, product, and odm partitions are moved
to the ./etc subdirectory. This is to be in-line with the established
practice of having all configuration files under ./etc subdir.
build.prop doesn't need to be an exception.
However, system/build.prop and vendor/build.prop were not moved because
there are a lot of apps and tools that depend on the path.
Bug: 158735147
Test: device has build.prop under ./etc and is bootable
Change-Id: I26300574c23c78cc4e5bc20f98fc9702838465e1
diff --git a/init/property_service.cpp b/init/property_service.cpp
index 612854d..b593b62 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -51,6 +51,7 @@
#include <android-base/chrono_utils.h>
#include <android-base/file.h>
#include <android-base/logging.h>
+#include <android-base/parseint.h>
#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
@@ -74,6 +75,7 @@
using namespace std::literals;
using android::base::GetProperty;
+using android::base::ParseInt;
using android::base::ReadFileToString;
using android::base::Split;
using android::base::StartsWith;
@@ -886,24 +888,60 @@
load_properties_from_file("/prop.default", nullptr, &properties);
}
+ // /<part>/etc/build.prop is the canonical location of the build-time properties since S.
+ // Falling back to /<part>/defalt.prop and /<part>/build.prop only when legacy path has to
+ // be supported, which is controlled by the support_legacy_path_until argument.
+ const auto load_properties_from_partition = [&properties](const std::string& partition,
+ int support_legacy_path_until) {
+ auto path = "/" + partition + "/etc/build.prop";
+ if (load_properties_from_file(path.c_str(), nullptr, &properties)) {
+ return;
+ }
+ // To read ro.<partition>.build.version.sdk, temporarily load the legacy paths into a
+ // separate map. Then by comparing its value with legacy_version, we know that if the
+ // partition is old enough so that we need to respect the legacy paths.
+ std::map<std::string, std::string> temp;
+ auto legacy_path1 = "/" + partition + "/default.prop";
+ auto legacy_path2 = "/" + partition + "/build.prop";
+ load_properties_from_file(legacy_path1.c_str(), nullptr, &temp);
+ load_properties_from_file(legacy_path2.c_str(), nullptr, &temp);
+ bool support_legacy_path = false;
+ auto version_prop_name = "ro." + partition + ".build.version.sdk";
+ auto it = temp.find(version_prop_name);
+ if (it == temp.end()) {
+ // This is embarassing. Without the prop, we can't determine how old the partition is.
+ // Let's be conservative by assuming it is very very old.
+ support_legacy_path = true;
+ } else if (int value;
+ ParseInt(it->second.c_str(), &value) && value <= support_legacy_path_until) {
+ support_legacy_path = true;
+ }
+ if (support_legacy_path) {
+ // We don't update temp into properties directly as it might skip any (future) logic
+ // for resolving duplicates implemented in load_properties_from_file. Instead, read
+ // the files again into the properties map.
+ load_properties_from_file(legacy_path1.c_str(), nullptr, &properties);
+ load_properties_from_file(legacy_path2.c_str(), nullptr, &properties);
+ } else {
+ LOG(FATAL) << legacy_path1 << " and " << legacy_path2 << " were not loaded "
+ << "because " << version_prop_name << "(" << it->second << ") is newer "
+ << "than " << support_legacy_path_until;
+ }
+ };
+
+ // Order matters here. The more the partition is specific to a product, the higher its
+ // precedence is.
load_properties_from_file("/system/build.prop", nullptr, &properties);
- load_properties_from_file("/system_ext/build.prop", nullptr, &properties);
-
- // TODO(b/117892318): uncomment the following condition when vendor.imgs for
- // aosp_* targets are all updated.
-// if (SelinuxGetVendorAndroidVersion() <= __ANDROID_API_R__) {
- load_properties_from_file("/vendor/default.prop", nullptr, &properties);
-// }
+ load_properties_from_partition("system_ext", /* support_legacy_path_until */ 30);
+ // TODO(b/117892318): uncomment the following condition when vendor.imgs for aosp_* targets are
+ // all updated.
+ // if (SelinuxGetVendorAndroidVersion() <= __ANDROID_API_R__) {
+ load_properties_from_file("/vendor/default.prop", nullptr, &properties);
+ // }
load_properties_from_file("/vendor/build.prop", nullptr, &properties);
+ load_properties_from_partition("odm", /* support_legacy_path_until */ 28);
+ load_properties_from_partition("product", /* support_legacy_path_until */ 30);
- if (SelinuxGetVendorAndroidVersion() >= __ANDROID_API_Q__) {
- load_properties_from_file("/odm/etc/build.prop", nullptr, &properties);
- } else {
- load_properties_from_file("/odm/default.prop", nullptr, &properties);
- load_properties_from_file("/odm/build.prop", nullptr, &properties);
- }
-
- load_properties_from_file("/product/build.prop", nullptr, &properties);
load_properties_from_file("/factory/factory.prop", "ro.*", &properties);
if (access(kDebugRamdiskProp, R_OK) == 0) {