lab1 code

.clang-format

@@ -0,0 +1,208 @@
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+AllowAllConstructorInitializersOnNextLine: true
+FixNamespaceComments: true
+ForEachMacros:
+  - foreach
+  - Q_FOREACH
+  - BOOST_FOREACH
+IfMacros:
+  - KJ_IF_MAYBE
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.vscode/settings.json

@@ -0,0 +1,60 @@
+{
+    "files.associations": {
+        "array": "cpp",
+        "atomic": "cpp",
+        "bit": "cpp",
+        "*.tcc": "cpp",
+        "cctype": "cpp",
+        "chrono": "cpp",
+        "clocale": "cpp",
+        "cmath": "cpp",
+        "compare": "cpp",
+        "concepts": "cpp",
+        "condition_variable": "cpp",
+        "cstdarg": "cpp",
+        "cstddef": "cpp",
+        "cstdint": "cpp",
+        "cstdio": "cpp",
+        "cstdlib": "cpp",
+        "ctime": "cpp",
+        "cwchar": "cpp",
+        "cwctype": "cpp",
+        "deque": "cpp",
+        "string": "cpp",
+        "unordered_map": "cpp",
+        "vector": "cpp",
+        "exception": "cpp",
+        "algorithm": "cpp",
+        "functional": "cpp",
+        "iterator": "cpp",
+        "memory": "cpp",
+        "memory_resource": "cpp",
+        "numeric": "cpp",
+        "random": "cpp",
+        "ratio": "cpp",
+        "string_view": "cpp",
+        "system_error": "cpp",
+        "tuple": "cpp",
+        "type_traits": "cpp",
+        "utility": "cpp",
+        "initializer_list": "cpp",
+        "iosfwd": "cpp",
+        "iostream": "cpp",
+        "istream": "cpp",
+        "limits": "cpp",
+        "mutex": "cpp",
+        "new": "cpp",
+        "numbers": "cpp",
+        "ostream": "cpp",
+        "semaphore": "cpp",
+        "stdexcept": "cpp",
+        "stop_token": "cpp",
+        "streambuf": "cpp",
+        "thread": "cpp",
+        "typeinfo": "cpp",
+        "syncstream": "cpp",
+        "csignal": "cpp",
+        "sstream": "cpp",
+        "fstream": "cpp"
+    }
+}

lab1/.gitignore

@@ -0,0 +1 @@
+build/

lab1/Makefile

@@ -3,7 +3,7 @@ OUT_BIN := $(OUT_DIR)/banker
 
 $(OUT_BIN): banker.cpp
 	mkdir -p $(OUT_DIR)
-	g++ -pthread banker.cpp -o $(OUT_BIN)
+	g++ -pthread --std=c++20 banker.cpp -o $(OUT_BIN)
 
 .PHONY: run
 run: $(OUT_BIN)

lab1/banker.cpp

@@ -1,22 +1,19 @@
-#include <iostream>
-#include <thread>
-#include <deque>
-#include <vector>
-#include <chrono>
 #include <atomic>
+#include <chrono>
+#include <csignal>
+#include <deque>
+#include <fstream>
+#include <iostream>
 #include <mutex>
 #include <semaphore>
+#include <sstream>
+#include <syncstream>
+#include <thread>
+#include <vector>
 
-#define TELLER_NUM 5
+#define TELLER_NUM 3
 #define TIME_GRAN_MSEC 200
 
-std::atomic<bool> bank_open = false;
-std::mutex custom_q_mtx;
-std::counting_semaphore custom_num_sem;
-
-std::deque<Customer> customer_q;
-
-
 struct CustomerInfo {
     unsigned int id;
     unsigned int arrival_time;
@@ -28,42 +25,164 @@ struct Customer {
     unsigned int service_time;
 };
 
-void teller_thread(int id, std::chrono::time_point<std::chrono::steady_clock> start_tick) {
+std::atomic<bool> bank_open{false};
-    std::cout << "Teller id " << id << " started\n";
+std::mutex customer_q_mtx;
+std::counting_semaphore<100> customer_num_sem{0};
+
+std::deque<Customer> customer_q;
+
+void signal_handler(int signum) {
+    // std::cout << "\nReceived signal " << signum << ", stopping...\n";
+    write(STDOUT_FILENO, "\nCaught SIGINT, shutting down...\n", 33);
+    bank_open = false;
+}
+
+void teller_thread(
+    int id, std::chrono::time_point<std::chrono::steady_clock> start_tick) {
+    std::osyncstream(std::cout)
+        << "Teller id " << id << " started" << std::endl;
     std::chrono::time_point curr_tick = start_tick;
+    unsigned int tick_count = 0;
     bool is_serving = false;
     std::chrono::time_point<std::chrono::steady_clock> start_serving_time;
     struct Customer curr_customer;
     while (bank_open) {
-        if (is_serving && ((curr_tick - start_serving_time) / TIME_GRAN_MSEC) >= curr_customer.service_time) {
+        if (is_serving) {
-            
+            if ((std::chrono::duration_cast<std::chrono::milliseconds>(
+                     (curr_tick - start_serving_time) / TIME_GRAN_MSEC))
+                    .count() <= curr_customer.service_time) {
+                // We are still serving, do nothing
+                std::osyncstream(std::cout) << "Teller id " << id << " is serving customer " << curr_customer.id << " at tick " << tick_count << std::endl;
+                goto next_tick;
+            } else {
+                // We have just finished serving.
+                std::osyncstream(std::cout) << "Teller id " << id << " finishied serving customer " << curr_customer.id << " at tick " << tick_count << std::endl;
+                is_serving = false;
+            }
         }
-        std::cout << "Teller id " << id << " waiting request\n";
-        
 
+        // Try to acquire a new customer
+        if (customer_num_sem.try_acquire()) {
+            // Successfully acquired a customer
+            std::lock_guard<std::mutex> lock(customer_q_mtx);
+            if (!customer_q.empty()) {
+                curr_customer = customer_q.front();
+                customer_q.pop_front();
+
+                std::osyncstream(std::cout)
+                    << "Teller id " << id << " is now serving customer "
+                    << curr_customer.id << " for " << curr_customer.service_time
+                    << " ticks at tick " << tick_count << std::endl;
+
+                is_serving = true;
+                start_serving_time = curr_tick;
+            }
+        } else {
+            std::osyncstream(std::cout)
+                << "Teller id " << id << " is idle at tick " << tick_count << std::endl;
+        }
+
+    next_tick:
+        ++tick_count;
         curr_tick += std::chrono::milliseconds(TIME_GRAN_MSEC);
         std::this_thread::sleep_until(curr_tick);
     }
-    std::cout << "Teller id " << id << " closing\n";
+    std::osyncstream(std::cout)
+        << "Teller id " << id << " closing" << std::endl;
 }
 
-int main() {
+void customer_thread(
-    bank_open = true;
+    CustomerInfo info,
+    std::chrono::time_point<std::chrono::steady_clock> start_tick) {
 
-    std::vector<std::thread> tellers;
+    Customer cus{.id = info.id, .service_time = info.service_time};
-    for (int i = 0; i < TELLER_NUM; ++i) {
+
-        try {
+    std::chrono::time_point curr_tick = start_tick;
-            tellers.emplace_back(teller_thread, i);
+    unsigned int tick_count = 0;
-        } catch (const std::system_error& e) {
+    std::chrono::time_point target_tick = start_tick + std::chrono::milliseconds(TIME_GRAN_MSEC) * info.arrival_time;
-            std::cerr << "Failed to create thread, i = " << i << ": " << e.what() << '\n';
+    while (curr_tick < target_tick) {
+        if (!bank_open) {
+            return;
+        }
+        ++tick_count;
+        curr_tick += std::chrono::milliseconds(TIME_GRAN_MSEC);
+        std::this_thread::sleep_until(curr_tick);
+    }
+    
+    // Wake up and push self into queue, then V(customer_num_sem)
+    std::osyncstream(std::cout) << "Customer id " << info.id << " arrived at tick " << tick_count << std::endl;
+    {
+        std::lock_guard<std::mutex> lock(customer_q_mtx);
+        customer_q.push_back(cus);
+    }
+    customer_num_sem.release();
+}
+
+int main(int argc, char *argv[]) {
+    if (argc != 2) {
+        std::cout << "Invalid commandline arg, expected filename";
+        return 1;
+    }
+
+    std::signal(SIGINT, signal_handler);
+
+    // Read config from file
+    std::vector<CustomerInfo> customer_infos;
+
+    std::ifstream file(argv[1]);
+    if (!file.is_open()) {
+        std::cerr << "Cannot open file: " << argv[1] << std::endl;
+        return 1;
+    }
+
+    std::string line;
+    while (std::getline(file, line)) {
+        std::istringstream iss(line);
+        CustomerInfo cus;
+        if (iss >> cus.id >> cus.arrival_time >> cus.service_time) {
+            customer_infos.push_back(cus);
+        } else {
+            std::cerr << "Invalid line: " << line << std::endl;
         }
     }
 
-    std::this_thread::sleep_for(std::chrono::milliseconds(5 * TIME_GRAN_MSEC));
+    file.close();
-    std::cout << "Closing all child\n";
-    bank_open = false;
 
-    for (auto& t : tellers) {
+    bank_open = true;
+    std::chrono::time_point start_tick = std::chrono::steady_clock::now();
+
+    // Set up tellers
+    std::vector<std::thread> tellers;
+
+    for (int i = 0; i < TELLER_NUM; ++i) {
+        try {
+            tellers.emplace_back(teller_thread, i, start_tick);
+        }
+        catch (const std::system_error &e) {
+            std::cerr << "Failed to create teller thread, i = " << i << ": "
+                      << e.what() << std::endl;
+        }
+    }
+
+    // Set up customers
+    std::vector<std::thread> customers;
+    for (auto cu : customer_infos) {
+        try {
+            customers.emplace_back(customer_thread, cu, start_tick);
+        } catch (const std::system_error &e) {
+            std::cerr << "Failed to create customer thread, id = " << cu.id << ": "
+                      << e.what() << std::endl;
+        }
+    }
+
+    // Wait for all children to shutdown (by ctrl-c handler)
+    for (auto &t: customers) {
+        if (t.joinable()) {
+            t.join();
+        }
+    }
+
+    for (auto &t : tellers) {
         if (t.joinable()) {
             t.join();
         }

lab1/test_data/1_out.txt

@@ -0,0 +1,71 @@
+Teller id 0 started
+Teller id 1 started
+Teller id 1 is idle at tick 0
+Teller id 0 is idle at tick 0
+Teller id 2 started
+Teller id 2 is idle at tick 0
+Teller id 0 is idle at tick 1
+Teller id 2 is idle at tick 1
+Teller id 1 is idle at tick 1
+Customer id 1 arrived at tick 1
+Teller id 0 is now serving customer 1 for 10 ticks at tick 2
+Teller id 1 is idle at tick 2
+Teller id 2 is idle at tick 2
+Teller id 0 is serving customer 1 at tick 3
+Teller id 1 is idle at tick 3
+Teller id 2 is idle at tick 3
+Teller id 0 is serving customer 1 at tick 4
+Teller id 1 is idle at tick 4
+Teller id 2 is idle at tick 4
+Teller id 0 is serving customer 1 at tick 5
+Customer id 2 arrived at tick 5
+Teller id 2 is idle at tick 5
+Teller id 1 is idle at tick 5
+Teller id 0 is serving customer 1 at tick 6
+Teller id 2 is now serving customer 2 for 2 ticks at tick 6
+Customer id 3 arrived at tick 6
+Teller id 1 is idle at tick 6
+Teller id 0 is serving customer 1 at tick 7
+Teller id 1 is now serving customer 3 for 3 ticks at tick 7
+Teller id 2 is serving customer 2 at tick 7
+Teller id 0 is serving customer 1 at tick 8
+Teller id 1 is serving customer 3 at tick 8
+Teller id 2 is serving customer 2 at tick 8
+Teller id 0 is serving customer 1 at tick 9
+Teller id 1 is serving customer 3 at tick 9
+Teller id 2 finishied serving customer 2 at tick 9
+Teller id 2 is idle at tick 9
+Teller id 1 is serving customer 3 at tick 10
+Teller id 0 is serving customer 1 at tick 10
+Teller id 2 is idle at tick 10
+Teller id 0 is serving customer 1 at tick 11
+Teller id 1 finishied serving customer 3 at tick 11
+Teller id 2 is idle at tick 11
+Teller id 1 is idle at tick 11
+Teller id 1 is idle at tick 12
+Teller id 2 is idle at tick 12
+Teller id 0 is serving customer 1 at tick 12
+Teller id 0 finishied serving customer 1 at tick 13
+Teller id 0 is idle at tick 13
+Teller id 2 is idle at tick 13
+Teller id 1 is idle at tick 13
+Teller id 0 is idle at tick 14
+Teller id 1 is idle at tick 14
+Teller id 2 is idle at tick 14
+Teller id 0 is idle at tick 15
+Teller id 2 is idle at tick 15
+Teller id 1 is idle at tick 15
+Teller id 0 is idle at tick 16
+Teller id 1 is idle at tick 16
+Teller id 2 is idle at tick 16
+Teller id 2 is idle at tick 17
+Teller id 0 is idle at tick 17
+Teller id 1 is idle at tick 17
+Teller id 0 is idle at tick 18
+Teller id 1 is idle at tick 18
+Teller id 2 is idle at tick 18
+^C
+Caught SIGINT, shutting down...
+Teller id 0 closing
+Teller id 1 closing
+Teller id 2 closing

lab1/test_data/2.txt

@@ -0,0 +1,7 @@
+1 1 10
+2 2 10
+3 3 10
+4 4 10
+5 5 5
+6 6 7
+8 7 10

lab1/test_data/2_out.txt

@@ -0,0 +1,130 @@
+Teller id 1 started
+Teller id 0 started
+Teller id 2 started
+Teller id 1 is idle at tick 0
+Teller id 2 is idle at tick 0
+Teller id 0 is idle at tick 0
+Teller id 0 is idle at tick 1
+Teller id 2 is idle at tick 1
+Teller id 1 is idle at tick 1
+Customer id 1 arrived at tick 1
+Teller id 0 is now serving customer 1 for 10 ticks at tick 2
+Teller id 1 is idle at tick 2
+Teller id 2 is idle at tick 2
+Customer id 2 arrived at tick 2
+Teller id 1 is now serving customer 2 for 10 ticks at tick 3
+Customer id 3 arrived at tick 3
+Teller id 0 is serving customer 1 at tick 3
+Teller id 2 is idle at tick 3
+Teller id 0 is serving customer 1 at tick 4
+Teller id 2 is now serving customer 3 for 10 ticks at tick 4
+Teller id 1 is serving customer 2 at tick 4
+Customer id 4 arrived at tick 4
+Teller id 0 is serving customer 1 at tick 5
+Teller id 2 is serving customer 3 at tick 5
+Teller id 1 is serving customer 2 at tick 5
+Customer id 5 arrived at tick 5
+Customer id 6 arrived at tick 6
+Teller id 1 is serving customer 2 at tick 6
+Teller id 0 is serving customer 1 at tick 6
+Teller id 2 is serving customer 3 at tick 6
+Teller id 1 is serving customer 2 at tick 7
+Teller id 0 is serving customer 1 at tick 7
+Customer id 8 arrived at tick 7
+Teller id 2 is serving customer 3 at tick 7
+Teller id 1 is serving customer 2 at tick 8
+Teller id 2 is serving customer 3 at tick 8
+Teller id 0 is serving customer 1 at tick 8
+Teller id 2 is serving customer 3 at tick 9
+Teller id 1 is serving customer 2 at tick 9
+Teller id 0 is serving customer 1 at tick 9
+Teller id 0 is serving customer 1 at tick 10
+Teller id 2 is serving customer 3 at tick 10
+Teller id 1 is serving customer 2 at tick 10
+Teller id 2 is serving customer 3 at tick 11
+Teller id 1 is serving customer 2 at tick 11
+Teller id 0 is serving customer 1 at tick 11
+Teller id 1 is serving customer 2 at tick 12
+Teller id 2 is serving customer 3 at tick 12
+Teller id 0 is serving customer 1 at tick 12
+Teller id 2 is serving customer 3 at tick 13
+Teller id 1 is serving customer 2 at tick 13
+Teller id 0 finishied serving customer 1 at tick 13
+Teller id 0 is now serving customer 4 for 10 ticks at tick 13
+Teller id 2 is serving customer 3 at tick 14
+Teller id 1 finishied serving customer 2 at tick 14
+Teller id 1 is now serving customer 5 for 5 ticks at tick 14
+Teller id 0 is serving customer 4 at tick 14
+Teller id 2 finishied serving customer 3 at tick 15
+Teller id 2 is now serving customer 6 for 7 ticks at tick 15
+Teller id 1 is serving customer 5 at tick 15
+Teller id 0 is serving customer 4 at tick 15
+Teller id 2 is serving customer 6 at tick 16
+Teller id 1 is serving customer 5 at tick 16
+Teller id 0 is serving customer 4 at tick 16
+Teller id 2 is serving customer 6 at tick 17
+Teller id 0 is serving customer 4 at tick 17
+Teller id 1 is serving customer 5 at tick 17
+Teller id 2 is serving customer 6 at tick 18
+Teller id 1 is serving customer 5 at tick 18
+Teller id 0 is serving customer 4 at tick 18
+Teller id 2 is serving customer 6 at tick 19
+Teller id 0 is serving customer 4 at tick 19
+Teller id 1 is serving customer 5 at tick 19
+Teller id 0 is serving customer 4 at tick 20
+Teller id 1 finishied serving customer 5 at tick 20
+Teller id 1 is now serving customer 8 for 10 ticks at tick 20
+Teller id 2 is serving customer 6 at tick 20
+Teller id 1 is serving customer 8 at tick 21
+Teller id 0 is serving customer 4 at tick 21
+Teller id 2 is serving customer 6 at tick 21
+Teller id 2 is serving customer 6 at tick 22
+Teller id 1 is serving customer 8 at tick 22
+Teller id 0 is serving customer 4 at tick 22
+Teller id 1 is serving customer 8 at tick 23
+Teller id 2 finishied serving customer 6 at tick 23
+Teller id 2 is idle at tick 23
+Teller id 0 is serving customer 4 at tick 23
+Teller id 1 is serving customer 8 at tick 24
+Teller id 0 finishied serving customer 4 at tick 24
+Teller id 2 is idle at tick 24
+Teller id 0 is idle at tick 24
+Teller id 1 is serving customer 8 at tick 25
+Teller id 2 is idle at tick 25
+Teller id 0 is idle at tick 25
+Teller id 1 is serving customer 8 at tick 26
+Teller id 2 is idle at tick 26
+Teller id 0 is idle at tick 26
+Teller id 1 is serving customer 8 at tick 27
+Teller id 0 is idle at tick 27
+Teller id 2 is idle at tick 27
+Teller id 1 is serving customer 8 at tick 28
+Teller id 2 is idle at tick 28
+Teller id 0 is idle at tick 28
+Teller id 1 is serving customer 8 at tick 29
+Teller id 2 is idle at tick 29
+Teller id 0 is idle at tick 29
+Teller id 1 is serving customer 8 at tick 30
+Teller id 0 is idle at tick 30
+Teller id 2 is idle at tick 30
+Teller id 1 finishied serving customer 8 at tick 31
+Teller id 1 is idle at tick 31
+Teller id 0 is idle at tick 31
+Teller id 2 is idle at tick 31
+Teller id 1 is idle at tick 32
+Teller id 2 is idle at tick 32
+Teller id 0 is idle at tick 32
+Teller id 1 is idle at tick 33
+Teller id 2 is idle at tick 33
+Teller id 0 is idle at tick 33
+Teller id 0 is idle at tick 34
+Teller id 1 is idle at tick 34
+Teller id 2 is idle at tick 34
+Teller id 0 is idle at tick 35
+Teller id 1 is idle at tick 35
+Teller id 2 is idle at tick 35
+^C
+Caught SIGINT, shutting down...
+Teller id 1 closing
+Teller id 0 closing
+Teller id 2 closing