Added support for generic loopback partition name parsing
Changed SplitPartitionName/MakePartitionName functions to
support generic device partition names where partition number
is separated from the disk name with 'p'. This used to be the
case only for MMC devices (/dev/mmcblk). But now, as long
as the disk name ends with a digit, then the following partition
name is assumed to be separated by 'p'.
Also added special case for NAND devices (/dev/ubiblock) to
be split and merged too, in order to make it possible to
use the split/merge functions with KernelDeviceOfBootDevice().
Updated KernelDeviceOfBootDevice() and GetInstallDev() to use
the SplitPartitionName/MakePartitionName functions.
Finally, updated the unit tests for ubiblock devices and added
unit tests for MakePartitionName function.
BUG=chromium:354494
TEST=Added/updated unit tests. All unit tests pass.
Change-Id: I8a813e13b315d118027bd84f179a0e569d0d4014
Reviewed-on: https://chromium-review.googlesource.com/191785
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/utils.cc b/utils.cc
index e379aae..0cde048 100644
--- a/utils.cc
+++ b/utils.cc
@@ -94,33 +94,26 @@
}
-const string KernelDeviceOfBootDevice(const std::string& boot_device) {
- if (boot_device.empty())
- return boot_device;
+const string KernelDeviceOfBootDevice(const string& boot_device) {
+ string kernel_partition_name;
- string ubiblock_prefix("/dev/ubiblock");
- string ret;
- char partition_num;
- if (StringHasPrefix(boot_device, ubiblock_prefix)) {
- // eg: /dev/ubiblock3_0 becomes /dev/mtdblock2
- ret = "/dev/mtdblock";
- partition_num = boot_device[ubiblock_prefix.size()];
- } else {
- // eg: /dev/sda3 becomes /dev/sda2
- // eg: /dev/mmcblk0p3 becomes /dev/mmcblk0p2
- ret = boot_device.substr(0, boot_device.size() - 1);
- partition_num = boot_device[boot_device.size() - 1];
+ string disk_name;
+ int partition_num;
+ if (SplitPartitionName(boot_device, &disk_name, &partition_num)) {
+ if (disk_name == "/dev/ubiblock") {
+ // Special case for NAND devices.
+ // eg: /dev/ubiblock3_0 becomes /dev/mtdblock2
+ disk_name = "/dev/mtdblock";
+ }
+ // Currently this assumes the partition number of the boot device is
+ // 3, 5, or 7, and changes it to 2, 4, or 6, respectively, to
+ // get the kernel device.
+ if (partition_num == 3 || partition_num == 5 || partition_num == 7) {
+ kernel_partition_name = MakePartitionName(disk_name, partition_num - 1);
+ }
}
- // Currently this assumes the partition number of the boot device is
- // 3, 5, or 7, and changes it to 2, 4, or 6, respectively, to
- // get the kernel device.
- if (partition_num == '3' || partition_num == '5' || partition_num == '7') {
- ret.append(1, partition_num - 1);
- return ret;
- }
-
- return "";
+ return kernel_partition_name;
}
@@ -395,32 +388,44 @@
return false;
}
- 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;
+ size_t last_nondigit_pos = partition_name.find_last_not_of("0123456789");
+ if (last_nondigit_pos == string::npos ||
+ (last_nondigit_pos + 1) == partition_name.size()) {
+ LOG(ERROR) << "Unable to parse partition device name: " << 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;
+ size_t partition_name_len = std::string::npos;
+ if (partition_name[last_nondigit_pos] == '_') {
+ // NAND block devices have weird naming which could be something
+ // like "/dev/ubiblock2_0". We discard "_0" in such a case.
+ size_t prev_nondigit_pos =
+ partition_name.find_last_not_of("0123456789", last_nondigit_pos - 1);
+ if (prev_nondigit_pos == string::npos ||
+ (prev_nondigit_pos + 1) == last_nondigit_pos) {
+ LOG(ERROR) << "Unable to parse partition device name: " << partition_name;
+ return false;
+ }
+
+ partition_name_len = last_nondigit_pos - prev_nondigit_pos;
+ last_nondigit_pos = prev_nondigit_pos;
}
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));
+ size_t disk_name_len = last_nondigit_pos;
+ if (partition_name[last_nondigit_pos] != 'p' ||
+ last_nondigit_pos == 0 ||
+ !isdigit(partition_name[last_nondigit_pos - 1])) {
+ disk_name_len++;
+ }
+ *out_disk_name = partition_name.substr(0, disk_name_len);
}
if (out_partition_num) {
- std::string partition_str = partition_name.substr(pos + 1);
+ std::string partition_str = partition_name.substr(last_nondigit_pos + 1,
+ partition_name_len);
*out_partition_num = atoi(partition_str.c_str());
}
return true;
@@ -439,13 +444,19 @@
}
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
+ if (isdigit(partition_name.back())) {
+ // Special case for devices with names ending with a digit.
+ // Add "p" to separate the disk name from partition number,
+ // e.g. "/dev/loop0p2"
partition_name += 'p';
}
- base::StringAppendF(&partition_name, "%d", partition_num);
+ partition_name += std::to_string(partition_num);
+
+ if (StringHasPrefix(partition_name, "/dev/ubiblock")) {
+ // Special case for UBI block devieces that have "_0" suffix.
+ partition_name += "_0";
+ }
return partition_name;
}
@@ -1309,23 +1320,22 @@
}
bool GetInstallDev(const std::string& boot_dev, std::string* install_dev) {
- TEST_AND_RETURN_FALSE(StringHasPrefix(boot_dev, "/dev/"));
- string::iterator it;
- string ubiblock_prefix("/dev/ubiblock");
-
- install_dev->assign(boot_dev);
-
- if(StringHasPrefix(boot_dev, ubiblock_prefix)) {
- // UBI-based device
- it = install_dev->begin() + ubiblock_prefix.length();
- } else {
- // non-UBI device
- it = install_dev->end() - 1; // last character in string
- }
+ std::string disk_name;
+ int partition_num;
+ if (!SplitPartitionName(boot_dev, &disk_name, &partition_num))
+ return false;
// Right now, we just switch '3' and '5' partition numbers.
- TEST_AND_RETURN_FALSE(*it == '3' || *it == '5');
- *it = (*it == '3' ? '5' : '3');
+ if (partition_num == 3) {
+ partition_num = 5;
+ } else if (partition_num == 5) {
+ partition_num = 3;
+ } else {
+ return false;
+ }
+
+ if (install_dev)
+ *install_dev = MakePartitionName(disk_name, partition_num);
return true;
}