diff --git a/tzdatacheck/tzdatacheck.cpp b/tzdatacheck/tzdatacheck.cpp index 381df5a83..8fcd17f7c 100644 --- a/tzdatacheck/tzdatacheck.cpp +++ b/tzdatacheck/tzdatacheck.cpp @@ -30,6 +30,19 @@ #include "android-base/logging.h" +// The name of the directory that holds a staged time zone update distro. If this exists it should +// replace the one in CURRENT_DIR_NAME. +// See also libcore.tzdata.update2.TimeZoneDistroInstaller. +static const char* STAGED_DIR_NAME = "/staged"; + +// The name of the directory that holds the (optional) installed time zone update distro. +// See also libcore.tzdata.update2.TimeZoneDistroInstaller. +static const char* CURRENT_DIR_NAME = "/current"; + +// The name of a file in the staged dir that indicates the staged operation is an "uninstall". +// See also libcore.tzdata.update2.TimeZoneDistroInstaller. +static const char* UNINSTALL_TOMBSTONE_FILE_NAME = "/STAGED_UNINSTALL_TOMBSTONE"; + // The name of the file containing the distro version information. // See also libcore.tzdata.shared2.TimeZoneDistro / libcore.tzdata.shared2.DistroVersion. static const char* DISTRO_VERSION_FILENAME = "/distro_version"; @@ -75,7 +88,6 @@ static const int TZ_HEADER_LENGTH = 11; static const char TZ_DATA_HEADER_PREFIX[] = "tzdata"; static const size_t TZ_DATA_HEADER_PREFIX_LEN = sizeof(TZ_DATA_HEADER_PREFIX) - 1; // exclude \0 - static void usage() { std::cerr << "Usage: tzdatacheck SYSTEM_TZ_DIR DATA_TZ_DIR\n" "\n" @@ -184,7 +196,7 @@ static int deleteFn(const char* fpath, const struct stat*, int typeflag, struct return 0; } -enum PathStatus { ERR, NONE, IS_DIR, NOT_DIR }; +enum PathStatus { ERR, NONE, IS_DIR, IS_REG, UNKNOWN }; static PathStatus checkPath(const std::string& path) { struct stat buf; @@ -195,7 +207,31 @@ static PathStatus checkPath(const std::string& path) { } return NONE; } - return S_ISDIR(buf.st_mode) ? IS_DIR : NOT_DIR; + return S_ISDIR(buf.st_mode) ? IS_DIR : S_ISREG(buf.st_mode) ? IS_REG : UNKNOWN; +} + +/* + * Deletes fileToDelete and returns true if it is successful. If fileToDelete is not a file or + * cannot be accessed this method returns false. + */ +static bool deleteFile(const std::string& fileToDelete) { + // Check whether the file exists. + PathStatus pathStatus = checkPath(fileToDelete); + if (pathStatus == NONE) { + LOG(INFO) << "Path " << fileToDelete << " does not exist"; + return true; + } + if (pathStatus != IS_REG) { + LOG(WARNING) << "Path " << fileToDelete << " failed to stat() or is not a file."; + return false; + } + + // Attempt the deletion. + int rc = unlink(fileToDelete.c_str()); + if (rc != 0) { + PLOG(WARNING) << "unlink() failed for " << fileToDelete; + } + return rc == 0; } /* @@ -260,8 +296,7 @@ static void deleteConfigUpdaterMetadataDir(const char* dataZoneInfoDir) { std::string dataUpdatesDirName(dataZoneInfoDir); dataUpdatesDirName += "/updates"; LOG(INFO) << "Removing: " << dataUpdatesDirName; - bool deleted = deleteDir(dataUpdatesDirName); - if (!deleted) { + if (!deleteDir(dataUpdatesDirName)) { LOG(WARNING) << "Deletion of install metadata " << dataUpdatesDirName << " was not successful"; } @@ -270,14 +305,151 @@ static void deleteConfigUpdaterMetadataDir(const char* dataZoneInfoDir) { /* * Deletes the timezone update distro directory. */ -static void deleteUpdateDistroDir(std::string& distroDirName) { +static void deleteUpdateDistroDir(const std::string& distroDirName) { LOG(INFO) << "Removing: " << distroDirName; - bool deleted = deleteDir(distroDirName); - if (!deleted) { + if (!deleteDir(distroDirName)) { LOG(WARNING) << "Deletion of distro dir " << distroDirName << " was not successful"; } } +static void handleStagedUninstall(const std::string& dataStagedDirName, + const std::string& dataCurrentDirName, + const PathStatus dataCurrentDirStatus) { + LOG(INFO) << "Staged operation is an uninstall."; + + // Delete the current install directory. + switch (dataCurrentDirStatus) { + case NONE: + // This is unexpected: No uninstall should be staged if there is nothing to + // uninstall. Carry on anyway. + LOG(WARNING) << "No current install to delete."; + break; + case IS_DIR: + // This is normal. Delete the current install dir. + if (!deleteDir(dataCurrentDirName)) { + LOG(WARNING) << "Deletion of current distro " << dataCurrentDirName + << " was not successful"; + // If this happens we don't know whether we were able to delete or not. We don't + // delete the staged operation so it will be retried next boot unless overridden. + return; + } + break; + case IS_REG: + default: + // This is unexpected: We can try to delete the unexpected file and carry on. + LOG(WARNING) << "Current distro dir " << dataCurrentDirName + << " is not actually a directory. Attempting deletion."; + if (!deleteFile(dataCurrentDirName)) { + LOG(WARNING) << "Could not delete " << dataCurrentDirName; + return; + } + break; + } + + // Delete the staged uninstall dir. + if (!deleteDir(dataStagedDirName)) { + LOG(WARNING) << "Deletion of current distro " << dataCurrentDirName + << " was not successful"; + // If this happens we don't know whether we were able to delete the staged operation + // or not. + return; + } + LOG(INFO) << "Staged uninstall complete."; +} + +static void handleStagedInstall(const std::string& dataStagedDirName, + const std::string& dataCurrentDirName, + const PathStatus dataCurrentDirStatus) { + LOG(INFO) << "Staged operation is an install."; + + switch (dataCurrentDirStatus) { + case NONE: + // This is expected: This is the first install. + LOG(INFO) << "No current install to replace."; + break; + case IS_DIR: + // This is expected: We are replacing an existing install. + // Delete the current dir so we can replace it. + if (!deleteDir(dataCurrentDirName)) { + LOG(WARNING) << "Deletion of current distro " << dataCurrentDirName + << " was not successful"; + // If this happens, we cannot proceed. + return; + } + break; + case IS_REG: + default: + // This is unexpected: We can try to delete the unexpected file and carry on. + LOG(WARNING) << "Current distro dir " << dataCurrentDirName + << " is not actually a directory. Attempting deletion."; + if (!deleteFile(dataCurrentDirName)) { + LOG(WARNING) << "Could not delete " << dataCurrentDirName; + return; + } + break; + } + + // Move the staged dir so it is the new current dir, completing the install. + LOG(INFO) << "Moving " << dataStagedDirName << " to " << dataCurrentDirName; + int rc = rename(dataStagedDirName.c_str(), dataCurrentDirName.c_str()); + if (rc == -1) { + PLOG(WARNING) << "Unable to rename directory from " << dataStagedDirName << " to " + << &dataCurrentDirName[0]; + return; + } + + LOG(INFO) << "Staged install complete."; +} +/* + * Process a staged operation if there is one. + */ +static void processStagedOperation(const std::string& dataStagedDirName, + const std::string& dataCurrentDirName) { + PathStatus dataStagedDirStatus = checkPath(dataStagedDirName); + + // Exit early for the common case. + if (dataStagedDirStatus == NONE) { + LOG(DEBUG) << "No staged time zone operation."; + return; + } + + // Check known directory names are in a good starting state. + if (dataStagedDirStatus != IS_DIR) { + LOG(WARNING) << "Staged distro dir " << dataStagedDirName + << " could not be accessed or is not a directory." + << " stagedDirStatus=" << dataStagedDirStatus; + return; + } + + // dataStagedDirStatus == IS_DIR. + + // Work out whether there is anything currently installed. + PathStatus dataCurrentDirStatus = checkPath(dataCurrentDirName); + if (dataCurrentDirStatus == ERR) { + LOG(WARNING) << "Current install dir " << dataCurrentDirName << " could not be accessed" + << " dataCurrentDirStatus=" << dataCurrentDirStatus; + return; + } + + // We must perform the staged operation. + + // Check to see if the staged directory contains an uninstall or an install operation. + std::string uninstallTombStoneFile(dataStagedDirName); + uninstallTombStoneFile += UNINSTALL_TOMBSTONE_FILE_NAME; + int uninstallTombStoneFileStatus = checkPath(uninstallTombStoneFile); + if (uninstallTombStoneFileStatus != IS_REG && uninstallTombStoneFileStatus != NONE) { + // Error case. + LOG(WARNING) << "Unable to determine if the staged operation is an uninstall."; + return; + } + if (uninstallTombStoneFileStatus == IS_REG) { + handleStagedUninstall(dataStagedDirName, dataCurrentDirName, dataCurrentDirStatus); + } else { + // uninstallTombStoneFileStatus == NONE meaning this is a staged install. + handleStagedInstall(dataStagedDirName, dataCurrentDirName, dataCurrentDirStatus); + } +} + /* * After a platform update it is likely that timezone data found on the system partition will be * newer than the version found in the data partition. This tool detects this case and removes the @@ -300,15 +472,25 @@ int main(int argc, char* argv[]) { const char* systemZoneInfoDir = argv[1]; const char* dataZoneInfoDir = argv[2]; - // Check the distro directory exists. If it does not, exit quickly: nothing to do. + std::string dataStagedDirName(dataZoneInfoDir); + dataStagedDirName += STAGED_DIR_NAME; + std::string dataCurrentDirName(dataZoneInfoDir); - dataCurrentDirName += "/current"; - int dataCurrentDirStatus = checkPath(dataCurrentDirName); + dataCurrentDirName += CURRENT_DIR_NAME; + + // Check for an process any staged operation. + // If the staged operation could not be handled we still have to validate the current installed + // directory so we do not check for errors and do not quit early. + processStagedOperation(dataStagedDirName, dataCurrentDirName); + + // Check the distro directory exists. If it does not, exit quickly: nothing to do. + PathStatus dataCurrentDirStatus = checkPath(dataCurrentDirName); if (dataCurrentDirStatus == NONE) { LOG(INFO) << "timezone distro dir " << dataCurrentDirName << " does not exist. No action required."; return 0; } + // If the distro directory path is not a directory or we can't stat() the path, exit with a // warning: either there's a problem accessing storage or the world is not as it should be; // nothing to do.