update_engine: added partition name manipulation library methods
Added utility methods to split and merge partition device names
to help "semi-intelligently" break down full partition device
name into disk name and partition name and merge them back.
With special handling for MMC devices and similar.
Also removed inconsistent naming for the disk and partition
device names (such as "boot device", "root device", etc).
Now device names such as "/dev/sda" are referred to as
"disk name" and "/dev/sda1" as "partition name").
BUG=None
TEST=Updated and ran unit tests
Change-Id: Ica41b8c99f0120799be326af0b41324639c5cf6a
Reviewed-on: https://chromium-review.googlesource.com/187453
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
diff --git a/hardware.cc b/hardware.cc
index 26435cf..9f3fe00 100644
--- a/hardware.cc
+++ b/hardware.cc
@@ -59,12 +59,14 @@
CgptAddParams params;
memset(¶ms, '\0', sizeof(params));
- string root_dev = utils::RootDevice(kernel_device);
- string partition_number_str = utils::PartitionNumber(kernel_device);
- uint32_t partition_number = atoi(partition_number_str.c_str());
+ std::string disk_name;
+ int partition_num = 0;
- params.drive_name = const_cast<char *>(root_dev.c_str());
- params.partition = partition_number;
+ if (!utils::SplitPartitionName(kernel_device, &disk_name, &partition_num))
+ return false;
+
+ params.drive_name = const_cast<char *>(disk_name.c_str());
+ params.partition = partition_num;
int retval = CgptGetPartitionDetails(¶ms);
if (retval != CGPT_OK)
@@ -82,15 +84,17 @@
return false;
}
- string root_dev = utils::RootDevice(kernel_device);
- string partition_number_str = utils::PartitionNumber(kernel_device);
- uint32_t partition_number = atoi(partition_number_str.c_str());
+ std::string disk_name;
+ int partition_num = 0;
+
+ if (!utils::SplitPartitionName(kernel_device, &disk_name, &partition_num))
+ return false;
CgptAddParams params;
memset(¶ms, 0, sizeof(params));
- params.drive_name = const_cast<char *>(root_dev.c_str());
- params.partition = partition_number;
+ params.drive_name = const_cast<char *>(disk_name.c_str());
+ params.partition = partition_num;
params.successful = false;
params.set_successful = true;
diff --git a/payload_state.cc b/payload_state.cc
index a23b545..7505b96 100644
--- a/payload_state.cc
+++ b/payload_state.cc
@@ -1166,13 +1166,13 @@
// payload was marked as ready immediately before the last reboot, and we
// need to check if such payload successfully rebooted or not.
if (prefs_->Exists(kPrefsTargetVersionInstalledFrom)) {
- string installed_from;
- if (!prefs_->GetString(kPrefsTargetVersionInstalledFrom, &installed_from)) {
+ int64_t installed_from = 0;
+ if (!prefs_->GetInt64(kPrefsTargetVersionInstalledFrom, &installed_from)) {
LOG(ERROR) << "Error reading TargetVersionInstalledFrom on reboot.";
return;
}
- if (installed_from ==
- utils::PartitionNumber(system_state_->hardware()->BootDevice())) {
+ if (int(installed_from) ==
+ utils::GetPartitionNumber(system_state_->hardware()->BootDevice())) {
// A reboot was pending, but the chromebook is again in the same
// BootDevice where the update was installed from.
int64_t target_attempt;
@@ -1221,8 +1221,8 @@
}
prefs_->SetInt64(kPrefsTargetVersionAttempt, target_attempt + 1);
- prefs_->SetString(kPrefsTargetVersionInstalledFrom,
- utils::PartitionNumber(
+ prefs_->SetInt64(kPrefsTargetVersionInstalledFrom,
+ utils::GetPartitionNumber(
system_state_->hardware()->BootDevice()));
}
diff --git a/update_check_scheduler.cc b/update_check_scheduler.cc
index 1835de9..682bae7 100644
--- a/update_check_scheduler.cc
+++ b/update_check_scheduler.cc
@@ -59,7 +59,7 @@
}
bool UpdateCheckScheduler::IsBootDeviceRemovable() {
- return utils::IsRemovableDevice(utils::RootDevice(
+ return utils::IsRemovableDevice(utils::GetDiskName(
system_state_->hardware()->BootDevice()));
}
diff --git a/utils.cc b/utils.cc
index 8a73cd7..7558f35 100644
--- a/utils.cc
+++ b/utils.cc
@@ -368,31 +368,78 @@
return true;
}
-string RootDevice(const string& partition_device) {
- FilePath device_path(partition_device);
- if (device_path.DirName().value() != "/dev") {
- return "";
- }
- string::const_iterator it = --partition_device.end();
- for (; it >= partition_device.begin(); --it) {
- if (!isdigit(*it))
- break;
- }
- // Some devices contain a p before the partitions. For example:
- // /dev/mmc0p4 should be shortened to /dev/mmc0.
- if (*it == 'p')
- --it;
- return string(partition_device.begin(), it + 1);
+std::string GetDiskName(const string& partition_name) {
+ std::string disk_name;
+ return SplitPartitionName(partition_name, &disk_name, nullptr) ?
+ disk_name : std::string();
}
-string PartitionNumber(const string& partition_device) {
- CHECK(!partition_device.empty());
- string::const_iterator it = --partition_device.end();
- for (; it >= partition_device.begin(); --it) {
- if (!isdigit(*it))
- break;
+int GetPartitionNumber(const std::string& partition_name) {
+ int partition_num = 0;
+ return SplitPartitionName(partition_name, nullptr, &partition_num) ?
+ partition_num : 0;
+}
+
+bool SplitPartitionName(const std::string& partition_name,
+ std::string* out_disk_name,
+ int* out_partition_num) {
+ if (!StringHasPrefix(partition_name, "/dev/")) {
+ LOG(ERROR) << "Invalid partition device name: " << partition_name;
+ return false;
}
- return string(it + 1, partition_device.end());
+
+ if (StringHasPrefix(partition_name, "/dev/ubiblock")) {
+ // NAND block devices have weird naming which could be something
+ // like "/dev/ubiblock2_0". Since update engine doesn't have proper
+ // support for NAND devices yet, don't bother parsing their names for now.
+ LOG(ERROR) << "UBI block devices are not supported: " << partition_name;
+ return false;
+ }
+
+ size_t pos = partition_name.find_last_not_of("0123456789");
+ if (pos == string::npos || (pos + 1) == partition_name.size()) {
+ LOG(ERROR) << "Unable to parse partition device name: "
+ << partition_name;
+ return false;
+ }
+
+ if (out_disk_name) {
+ // Special case for MMC devices which have the following naming scheme:
+ // mmcblk0p2
+ bool valid_mmc_device = StringHasPrefix(partition_name, "/dev/mmcblk") &&
+ partition_name[pos] == 'p';
+ *out_disk_name =
+ partition_name.substr(0, valid_mmc_device ? pos : (pos + 1));
+ }
+
+ if (out_partition_num) {
+ std::string partition_str = partition_name.substr(pos + 1);
+ *out_partition_num = atoi(partition_str.c_str());
+ }
+ return true;
+}
+
+std::string MakePartitionName(const std::string& disk_name,
+ int partition_num) {
+ if (!StringHasPrefix(disk_name, "/dev/")) {
+ LOG(ERROR) << "Invalid disk name: " << disk_name;
+ return std::string();
+ }
+
+ if (partition_num < 1) {
+ LOG(ERROR) << "Invalid partition number: " << partition_num;
+ return std::string();
+ }
+
+ std::string partition_name = disk_name;
+ if (!StringHasPrefix(disk_name, "/dev/mmcblk")) {
+ // Special case for MMC devices. Add "p" to separate the disk name
+ // from partition number
+ partition_name += 'p';
+ }
+
+ base::StringAppendF(&partition_name, "%d", partition_num);
+ return partition_name;
}
string SysfsBlockDevice(const string& device) {
diff --git a/utils.h b/utils.h
index 3e1fd16..a84f512 100644
--- a/utils.h
+++ b/utils.h
@@ -136,14 +136,35 @@
// This WILL cross filesystem boundaries.
bool RecursiveUnlinkDir(const std::string& path);
-// Returns the root device for a partition. For example,
-// RootDevice("/dev/sda3") returns "/dev/sda". Returns an empty string
-// if the input device is not of the "/dev/xyz" form.
-std::string RootDevice(const std::string& partition_device);
+// Returns the disk device name for a partition. For example,
+// GetDiskName("/dev/sda3") returns "/dev/sda". Returns an empty string
+// if the input device is not of the "/dev/xyz#" form.
+std::string GetDiskName(const std::string& partition_name);
-// Returns the partition number, as a string, of partition_device. For example,
-// PartitionNumber("/dev/sda3") returns "3".
-std::string PartitionNumber(const std::string& partition_device);
+// Returns the partition number, of partition device name. For example,
+// GetPartitionNumber("/dev/sda3") returns 3.
+// Returns 0 on failure
+int GetPartitionNumber(const std::string& partition_name);
+
+// Splits the partition device name into the block device name and partition
+// number. For example, "/dev/sda3" will be split into {"/dev/sda", 3} and
+// "/dev/mmcblk0p2" into {"/dev/mmcblk0", 2}
+// Returns false when malformed device name is passed in.
+// If both output parameters are omitted (nullptr), can be used
+// just to test the validity of the device name. Note that the function
+// simply checks if the device name looks like a valid device, no other
+// checks are performed (i.e. it doesn't check if the device actually exists).
+bool SplitPartitionName(const std::string& partition_name,
+ std::string* out_disk_name,
+ int* out_partition_num);
+
+// Builds a partition device name from the block device name and partition
+// number. For example:
+// {"/dev/sda", 1} => "/dev/sda1"
+// {"/dev/mmcblk2", 12} => "/dev/mmcblk2p12"
+// Returns empty string when invalid parameters are passed in
+std::string MakePartitionName(const std::string& disk_name,
+ int partition_num);
// Returns the sysfs block device for a root block device. For
// example, SysfsBlockDevice("/dev/sda") returns
diff --git a/utils_unittest.cc b/utils_unittest.cc
index 8602337..d75a6b0 100644
--- a/utils_unittest.cc
+++ b/utils_unittest.cc
@@ -202,12 +202,16 @@
EXPECT_FALSE(utils::StringHasSuffix(result, "XXXXXX"));
}
-TEST(UtilsTest, RootDeviceTest) {
- EXPECT_EQ("/dev/sda", utils::RootDevice("/dev/sda3"));
- EXPECT_EQ("/dev/mmc0", utils::RootDevice("/dev/mmc0p3"));
- EXPECT_EQ("", utils::RootDevice("/dev/foo/bar"));
- EXPECT_EQ("", utils::RootDevice("/"));
- EXPECT_EQ("", utils::RootDevice(""));
+TEST(UtilsTest, GetDiskNameTest) {
+ EXPECT_EQ("/dev/sda", utils::GetDiskName("/dev/sda3"));
+ EXPECT_EQ("/dev/sda", utils::GetDiskName("/dev/sda1234"));
+ EXPECT_EQ("/dev/mmcblk0", utils::GetDiskName("/dev/mmcblk0p3"));
+ EXPECT_EQ("", utils::GetDiskName("/dev/mmcblk0p"));
+ EXPECT_EQ("", utils::GetDiskName("/dev/sda"));
+ EXPECT_EQ("", utils::GetDiskName("/dev/ubiblock3_2"));
+ EXPECT_EQ("", utils::GetDiskName("/dev/foo/bar"));
+ EXPECT_EQ("", utils::GetDiskName("/"));
+ EXPECT_EQ("", utils::GetDiskName(""));
}
TEST(UtilsTest, SysfsBlockDeviceTest) {
@@ -224,9 +228,16 @@
EXPECT_FALSE(utils::IsRemovableDevice("/dev/non-existent-device"));
}
-TEST(UtilsTest, PartitionNumberTest) {
- EXPECT_EQ("3", utils::PartitionNumber("/dev/sda3"));
- EXPECT_EQ("3", utils::PartitionNumber("/dev/mmc0p3"));
+TEST(UtilsTest, GetPartitionNumberTest) {
+ EXPECT_EQ(3, utils::GetPartitionNumber("/dev/sda3"));
+ EXPECT_EQ(123, utils::GetPartitionNumber("/dev/sda123"));
+ EXPECT_EQ(2, utils::GetPartitionNumber("/dev/mmcblk0p2"));
+ EXPECT_EQ(0, utils::GetPartitionNumber("/dev/mmcblk0p"));
+ EXPECT_EQ(0, utils::GetPartitionNumber("/dev/ubiblock3_2"));
+ EXPECT_EQ(0, utils::GetPartitionNumber(""));
+ EXPECT_EQ(0, utils::GetPartitionNumber("/"));
+ EXPECT_EQ(0, utils::GetPartitionNumber("/dev/"));
+ EXPECT_EQ(0, utils::GetPartitionNumber("/dev/sda"));
}
TEST(UtilsTest, CompareCpuSharesTest) {