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Merge "init: mount_handler: system-as-root (legacy)"

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Treehugger Robot 2019-03-28 18:25:27 +00:00 • committed by Gerrit Code Review
commit a896e2aee5
1 changed files with 29 additions and 15 deletions
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44
init/mount_handler.cpp
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@ -27,6 +27,7 @@
#include <algorithm> #include <algorithm>
#include <string> #include <string>
#include <utility> #include <utility>
#include <vector>
#include <android-base/file.h> #include <android-base/file.h>
#include <android-base/logging.h> #include <android-base/logging.h>
@ -34,6 +35,7 @@
#include <android-base/strings.h> #include <android-base/strings.h>
#include <fs_mgr.h> #include <fs_mgr.h>
#include <fstab/fstab.h> #include <fstab/fstab.h>
#include <libdm/dm.h>
#include "epoll.h" #include "epoll.h"
#include "property_service.h" #include "property_service.h"
@ -47,8 +49,13 @@ MountHandlerEntry ParseMount(const std::string& line) {
auto fields = android::base::Split(line, " "); auto fields = android::base::Split(line, " ");
while (fields.size() < 3) fields.emplace_back(""); while (fields.size() < 3) fields.emplace_back("");
if (fields[0] == "/dev/root") { if (fields[0] == "/dev/root") {
if (android::fs_mgr::Fstab fstab; android::fs_mgr::ReadDefaultFstab(&fstab)) { auto& dm = dm::DeviceMapper::Instance();
if (auto entry = GetEntryForMountPoint(&fstab, "/")) { std::string path;
if (dm.GetDmDevicePathByName("system", &path) || dm.GetDmDevicePathByName("vroot", &path)) {
fields[0] = path;
} else if (android::fs_mgr::Fstab fstab; android::fs_mgr::ReadDefaultFstab(&fstab)) {
auto entry = GetEntryForMountPoint(&fstab, "/");
if (entry || (entry = GetEntryForMountPoint(&fstab, "/system"))) {
fields[0] = entry->blk_device; fields[0] = entry->blk_device;
} }
} }
@ -77,14 +84,19 @@ void SetMountProperty(const MountHandlerEntry& entry, bool add) {
struct stat sb; struct stat sb;
if (stat(queue.c_str(), &sb) || !S_ISDIR(sb.st_mode)) value = ""; if (stat(queue.c_str(), &sb) || !S_ISDIR(sb.st_mode)) value = "";
if (stat(entry.mount_point.c_str(), &sb) || !S_ISDIR(sb.st_mode)) value = ""; if (stat(entry.mount_point.c_str(), &sb) || !S_ISDIR(sb.st_mode)) value = "";
// Skip the noise associated with APEX until there is a need // Clear the noise associated with loopback and APEX.
if (android::base::StartsWith(value, "loop")) value = ""; if (android::base::StartsWith(value, "loop")) value = "";
if (android::base::StartsWith(entry.mount_point, "/apex/")) value = "";
} }
std::string property = auto mount_prop = entry.mount_point;
"dev.mnt.blk" + ((entry.mount_point == "/") ? "/root" : entry.mount_point); if (mount_prop == "/") mount_prop = "/root";
std::replace(property.begin(), property.end(), '/', '.'); std::replace(mount_prop.begin(), mount_prop.end(), '/', '.');
if (value.empty() && android::base::GetProperty(property, "").empty()) return; mount_prop = "dev.mnt.blk" + mount_prop;
property_set(property, value); // Set property even if its value does not change to trigger 'on property:'
// handling, except for clearing non-existent or already clear property.
// Goal is reduction of empty properties and associated triggers.
if (value.empty() && android::base::GetProperty(mount_prop, "").empty()) return;
property_set(mount_prop, value);
} }
} // namespace } // namespace
@ -114,25 +126,27 @@ MountHandler::~MountHandler() {
void MountHandler::MountHandlerFunction() { void MountHandler::MountHandlerFunction() {
rewind(fp_.get()); rewind(fp_.get());
std::vector<MountHandlerEntry> touched;
auto untouched = mounts_;
char* buf = nullptr; char* buf = nullptr;
size_t len = 0; size_t len = 0;
auto untouched = mounts_;
while (getline(&buf, &len, fp_.get()) != -1) { while (getline(&buf, &len, fp_.get()) != -1) {
auto entry = ParseMount(std::string(buf, len)); auto entry = ParseMount(std::string(buf));
auto match = untouched.find(entry); auto match = untouched.find(entry);
if (match == untouched.end()) { if (match == untouched.end()) {
SetMountProperty(entry, true); touched.emplace_back(std::move(entry));
mounts_.emplace(std::move(entry));
} else { } else {
untouched.erase(match); untouched.erase(match);
} }
} }
free(buf); free(buf);
for (auto entry : untouched) { for (auto entry : untouched) {
auto match = mounts_.find(entry);
if (match == mounts_.end()) continue;
mounts_.erase(match);
SetMountProperty(entry, false); SetMountProperty(entry, false);
mounts_.erase(entry);
}
for (auto entry : touched) {
SetMountProperty(entry, true);
mounts_.emplace(std::move(entry));
} }
} }