feat(judger): support non-integer time limit (#15)

本 Pull Request 通过将时间限制解析为浮点数的方式，实现了对非整数时间限制的支持。

---

ref: https://github.com/vfleaking/uoj/pull/100

judger/uoj_judger/include/uoj_judger.h

@@ -633,6 +633,23 @@ int conf_int(const string &key, int num, const int &val) {
 int conf_int(const string &key)  {
 	return conf_int(key, 0);
 }
+double conf_double(const string &key, const double &val) {
+	if (config.count(key) == 0) {
+		return val;
+	}
+	return stod(config[key]);
+}
+double conf_double(const string &key, int num, const double &val) {
+	ostringstream sout;
+	sout << key << "_" << num;
+	if (config.count(sout.str()) == 0) {
+		return conf_double(key, val);
+	}
+	return stod(config[sout.str()]);
+}
+double conf_double(const string &key) {
+	return conf_double(key, 0);
+}
 string conf_file_name_with_num(string s, int num) {
 	ostringstream name;
 	if (num < 0) {
@@ -664,10 +681,10 @@ runp::limits_t conf_run_limit(string pre, const int &num, const runp::limits_t &
 		pre += "_";
 	}
 	runp::limits_t limits;
-	limits.time = conf_int(pre + "time_limit", num, val.time);
+	limits.time = conf_double(pre + "time_limit", num, val.time);
 	limits.memory = conf_int(pre + "memory_limit", num, val.memory);
 	limits.output = conf_int(pre + "output_limit", num, val.output);
-	limits.real_time = conf_int(pre + "real_time_limit", num, val.real_time);
+	limits.real_time = conf_double(pre + "real_time_limit", num, val.real_time);
 	limits.stack = conf_int(pre + "stack_limit", num, val.stack);
 	return limits;
 }

judger/uoj_judger/include/uoj_judger_v2.h

@@ -501,6 +501,23 @@ int conf_int(const string &key, int num, const int &val) {
 int conf_int(const string &key)  {
 	return conf_int(key, 0);
 }
+double conf_double(const string &key, const double &val) {
+	if (uconfig.count(key) == 0) {
+		return val;
+	}
+	return stod(uconfig[key]);
+}
+double conf_double(const string &key, int num, const double &val) {
+	ostringstream sout;
+	sout << key << "_" << num;
+	if (uconfig.count(sout.str()) == 0) {
+		return conf_double(key, val);
+	}
+	return stod(uconfig[sout.str()]);
+}
+double conf_double(const string &key) {
+	return conf_double(key, 0);
+}
 string conf_file_name_with_num(string s, int num) {
 	ostringstream name;
 	if (num < 0) {
@@ -530,10 +547,10 @@ runp::limits_t conf_run_limit(string pre, const int &num, const runp::limits_t &
 		pre += "_";
 	}
 	runp::limits_t limits;
-	limits.time = conf_int(pre + "time_limit", num, val.time);
+	limits.time = conf_double(pre + "time_limit", num, val.time);
 	limits.memory = conf_int(pre + "memory_limit", num, val.memory);
 	limits.output = conf_int(pre + "output_limit", num, val.output);
-	limits.real_time = conf_int(pre + "real_time_limit", num, val.real_time);
+	limits.real_time = conf_double(pre + "real_time_limit", num, val.real_time);
 	limits.stack = conf_int(pre + "stack_limit", num, val.real_time);
 	return limits;
 }

judger/uoj_judger/include/uoj_run.h

@@ -1,3 +1,4 @@
+#include <cmath>
 #include <string>
 #include <vector>
 #include <map>
@@ -7,6 +8,7 @@
 #include <filesystem>
 #include <exception>
 #include <stdexcept>
+#include <sys/time.h>
 
 #define UOJ_GCC "/usr/bin/gcc-11"
 #define UOJ_GPLUSPLUS "/usr/bin/g++-11"
@@ -20,6 +22,11 @@
 std::string escapeshellarg(int arg) {
 	return std::to_string(arg);
 }
+std::string escapeshellarg(double arg) {
+	std::ostringstream sout;
+	sout << std::setprecision(15) << arg;
+	return sout.str();
+}
 std::string escapeshellarg(const std::string &arg) {
 	std::string res = "'";
 	for (char c : arg) {
@@ -133,14 +140,14 @@ namespace runp {
 	fs::path run_path;
 
 	struct limits_t {
-		int time;
+		double time;
 		int memory;
 		int output;
-		int real_time;
+		double real_time;
 		int stack;
 
 		limits_t() = default;
-		limits_t(const int &_time, const int &_memory, const int &_output)
+		limits_t(const double &_time, const int &_memory, const int &_output)
 				: time(_time), memory(_memory), output(_output), real_time(-1), stack(-1) {
 		}
 	};
@@ -388,6 +395,32 @@ namespace runp {
 			}
 		}
 	};
+
+	/**
+	 * @brief convert a time t to timeval. Assume t <= 1000. Accurate to ms.
+	 * 
+	 * @param t time in double
+	 * @return timeval
+	 */
+	timeval double_to_timeval(const double &t) {
+		long tl = round(t * 1000);
+		long tl_sec = tl / 1000;
+		long tl_usec = tl % 1000 * 1000;
+		return {tl_sec, tl_usec};
+	}
+
+	/**
+	 * @brief convert a time t to timespec. Assume t <= 1000. Accurate to ms.
+	 * 
+	 * @param t time in double
+	 * @return timespec
+	 */
+	timespec double_to_timespec(const double &t) {
+		long tl = round(t * 1000);
+		long tl_sec = tl / 1000;
+		long tl_nsec = tl % 1000 * 1'000'000;
+		return {tl_sec, tl_nsec};
+	}
 }
 
 namespace runp::interaction {

judger/uoj_judger/run/run_program.cpp

@@ -51,10 +51,10 @@ error_t run_program_argp_parse_opt (int key, char *arg, struct argp_state *state
 
 	switch (key) {
 		case 'T':
-			config->limits.time = atoi(arg);
+			config->limits.time = round(stod(arg) * 1000) / 1000;
 			break;
 		case 'R':
-			config->limits.real_time = atoi(arg);
+			config->limits.real_time = round(stod(arg) * 1000) / 1000;
 			break;
 		case 'M':
 			config->limits.memory = atoi(arg);
@@ -201,10 +201,17 @@ void set_limit(int r, int rcur, int rmax = -1)  {
 	}
 }
 
-void set_user_cpu_time_limit(int tl) {
+void set_user_cpu_time_limit(double tl) {
-	struct itimerval val;
+	itimerval val;
-	val.it_value = {tl, 100 * 1000};
+	val.it_value = runp::double_to_timeval(tl);
-	val.it_interval = {0, 100 * 1000};
+	val.it_interval = {0, 100'000};
+
+	val.it_value.tv_usec += 100'000;
+	if (val.it_value.tv_usec >= 1'000'000) {
+		val.it_value.tv_sec++;
+		val.it_value.tv_usec -= 1'000'000;
+	}
+
 	setitimer(ITIMER_VIRTUAL, &val, NULL);
 }
 
@@ -304,7 +311,7 @@ struct rusage *ruse0p = NULL;
 bool has_real_TLE() {
 	struct timeval elapsed;
 	timersub(&end_time, &start_time, &elapsed);
-	return elapsed.tv_sec >= run_program_config.limits.real_time;
+	return elapsed.tv_sec + elapsed.tv_usec / 1'000'000. >= run_program_config.limits.real_time;
 }
 
 int rp_children_pos(pid_t pid) {
@@ -630,9 +637,12 @@ void dispatch_event(run_event&& e) {
 	if (rp_timer_pid == -1) {
 		runp::result(runp::RS_JGF, "error code: FKFAL2").dump_and_exit(); // fork failed
 	} else if (rp_timer_pid == 0) {
-		struct timespec ts;
+		struct timespec ts = runp::double_to_timespec(run_program_config.limits.real_time);
-		ts.tv_sec = run_program_config.limits.real_time;
+		ts.tv_nsec += 100'000'000;
-		ts.tv_nsec = 100 * 1000000;
+		if (ts.tv_nsec >= 1'000'000'000) {
+			ts.tv_sec += 1;
+			ts.tv_nsec -= 1'000'000'000;
+		}
 		nanosleep(&ts, NULL);
 		exit(0);
 	}

judger/uoj_judger/run/run_program_sandbox.h

@@ -14,7 +14,6 @@
 #include <sys/stat.h>
 #include <sys/resource.h>
 #include <sys/user.h>
-#include <sys/time.h>
 #include <sys/prctl.h>
 #include <fcntl.h>
 #include <argp.h>