off_t SysInfo::partition_size()

in src/sys_info.cc [342:367]

• 21 lines of code
• 3 McCabe index (conditional complexity)

	off_t SysInfo::partition_size(dev_t device_id) {
		if (!id_to_device.count(device_id)) {
			fprintf(
					stderr,
					"Tried to lookup nonexistent device %u,%u in sys_info!\n",
					major(device_id),
					minor(device_id));
			exit(1);
		}

		std::string line;
		std::ifstream sizefile("/sys/class/block/" + id_to_device[device_id] + "/size");

		if (!sizefile.is_open()) {
			fprintf(stderr, "Couldn't open size file for device\n");
			exit(1);
		}

		std::getline(sizefile, line);

		sizefile.close();
		
		unsigned long long sz = strtoull(line.c_str(), NULL, 10);
		sz *= 512;	// linux treats all devices as having a sector size of 512
		return static_cast<off_t>(sz);
	}