fork download
copy 
  1. #include <stdio.h>
  2. #include <semaphore.h>
  3. #include <pthread.h>
  4.  
  5. #define BUFFER_SIZE 100 // Adjust buffer size as needed
  6.  
  7. sem_t mutex, full, empty;
  8. int buff[BUFFER_SIZE];
  9. int in = 0, out = 0; // Indexes for producer and consumer
  10.  
  11. void producer(void *arg) {
  12.     int item;
  13.     while (1) {
  14.         printf("Enter the item to be produced (or -1 to exit): ");
  15.         if (scanf("%d", &item) != 1 || item == -1) {
  16.             break; // Exit producer if user enters -1 or input error
  17.         }
  18.  
  19.         sem_wait(&empty); // Wait if buffer is full
  20.         sem_wait(&mutex);  // Enter critical section
  21.  
  22.         // Critical section: Add item to buffer
  23.         buff[in] = item;
  24.         printf("Item %d stored in buffer\n", buff[in]);
  25.         in = (in + 1) % BUFFER_SIZE; // Circular buffer logic
  26.  
  27.         sem_post(&mutex);  // Exit critical section
  28.         sem_post(&full);   // Signal a full slot
  29.     }
  30. }
  31.  
  32. void consumer(void *arg) {
  33.     int item;
  34.     while (1) {
  35.         sem_wait(&full); // Wait if buffer is empty
  36.         sem_wait(&mutex);  // Enter critical section
  37.  
  38.         // Critical section: Remove item from buffer
  39.         item = buff[out];
  40.         printf("Item %d consumed from buffer\n", item);
  41.         out = (out + 1) % BUFFER_SIZE; // Circular buffer logic
  42.  
  43.         sem_post(&mutex);  // Exit critical section
  44.         sem_post(&empty);   // Signal an empty slot
  45.     }
  46. }
  47.  
  48. int main() {
  49.     int m, n; // Number of producers and consumers
  50.  
  51.     printf("Enter the number of producers: ");
  52.     scanf("%d", &m);
  53.     printf("Enter the number of consumers: ");
  54.     scanf("%d", &n);
  55.  
  56.     // Semaphore initialization (corrected initialization values)
  57.     sem_init(&mutex, 0, 1);
  58.     sem_init(&full, 0, 0);  // Initially no full slots
  59.     sem_init(&empty, 0, BUFFER_SIZE); // Initially all slots empty
  60.  
  61.     // Thread creation
  62.     pthread_t producers[m], consumers[n];
  63.     for (int i = 0; i < m; i++) {
  64.         pthread_create(&producers[i], NULL, producer, NULL);
  65.     }
  66.     for (int i = 0; i < n; i++) {
  67.         pthread_create(&consumers[i], NULL, consumer, NULL);
  68.     }
  69.  
  70.     // Wait for threads to finish
  71.     for (int i = 0; i < m; i++) {
  72.         pthread_join(producers[i], NULL);
  73.     }
  74.     for (int i = 0; i < n; i++) {
  75.         pthread_join(consumers[i], NULL);
  76.     }
  77.  
  78.     printf("All producers and consumers finished.\n");
  79.     return 0;
  80. }
  81.  
Success #stdin #stdout 0.01s 5316KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Enter the number of producers: Enter the number of consumers: All producers and consumers finished.
https://ideone.com/6qKzbO
language:
C (gcc 8.3)
created:
10 days ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!