Implement multi-core CPU utilization for wssshc

- Added CPU affinity management to distribute tunnel threads across available CPU cores
- Implemented round-robin CPU core assignment for optimal load distribution
- Added _GNU_SOURCE define to enable CPU affinity functions
- Updated configure.sh to include -D_GNU_SOURCE in CFLAGS for proper compilation
- Enhanced parallel processing capabilities for multiple concurrent tunnels
- Updated CHANGELOG.md and TODO.md with multi-core optimization details

CHANGELOG.md

@@ -19,6 +19,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   - Increased select() timeout from 50ms to 200ms in tunnel forwarding threads
   - Reduced polling frequency by 75% to minimize CPU overhead during data transfers
   - Maintained responsiveness while dramatically improving efficiency for bulk transfers
+- **Multi-Core CPU Utilization**: Enhanced thread distribution across CPU cores
+  - Implemented CPU affinity management for tunnel forwarding threads
+  - Added round-robin CPU core assignment to distribute load across available cores
+  - Improved parallel processing capabilities for multiple concurrent tunnels
 
 ### Technical Details
 - **Import Management**: Added explicit `websockets` import to server.py for PyInstaller compatibility

TODO.md

@@ -10,6 +10,10 @@
   - Increased select() timeout from 50ms to 200ms in tunnel forwarding threads
   - Reduced polling frequency by 75% to minimize CPU overhead during data transfers
   - Maintained responsiveness while dramatically improving efficiency for bulk transfers
+- [x] **Multi-Core CPU Utilization**: Enhanced thread distribution across CPU cores
+  - Implemented CPU affinity management for tunnel forwarding threads
+  - Added round-robin CPU core assignment to distribute load across available cores
+  - Improved parallel processing capabilities for multiple concurrent tunnels
 
 ## Recently Completed (v1.4.8)
 - [x] **Critical SSL Connection Stability Issues**: Comprehensive SSL error handling and connection resilience improvements

wssshtools/configure.sh

@@ -52,7 +52,7 @@ cat > Makefile << 'EOF'
 # Makefile for wssshtools
 
 CC = gcc
-CFLAGS = -Wall -Wextra -O2 $(shell pkg-config --cflags openssl)
+CFLAGS = -Wall -Wextra -O2 -D_GNU_SOURCE $(shell pkg-config --cflags openssl)
 LDFLAGS = $(shell pkg-config --libs openssl)
 
 # Source files

wssshtools/tunnel.c

@@ -31,6 +31,8 @@
 #include <netdb.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <sched.h>
+#include <pthread.h>
 
 #define INITIAL_FRAME_BUFFER_SIZE 8192
 
@@ -44,6 +46,41 @@ pthread_mutex_t tunnel_mutex = PTHREAD_MUTEX_INITIALIZER;
 // Global shutdown flag for threads
 volatile int global_shutdown = 0;
 
+// CPU affinity management
+static int num_cpu_cores = 0;
+static int next_cpu_core = 0;
+static pthread_mutex_t cpu_affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+// Initialize CPU core detection
+void init_cpu_affinity() {
+    num_cpu_cores = sysconf(_SC_NPROCESSORS_ONLN);
+    if (num_cpu_cores <= 0) {
+        num_cpu_cores = 1;  // Fallback to 1 core
+    }
+    next_cpu_core = 0;
+}
+
+// Set CPU affinity for a thread to distribute across cores
+void set_thread_cpu_affinity(pthread_t thread) {
+    if (num_cpu_cores <= 1) {
+        return;  // No need to set affinity for single core
+    }
+
+    pthread_mutex_lock(&cpu_affinity_mutex);
+    int target_core = next_cpu_core;
+    next_cpu_core = (next_cpu_core + 1) % num_cpu_cores;
+    pthread_mutex_unlock(&cpu_affinity_mutex);
+
+    cpu_set_t cpuset;
+    CPU_ZERO(&cpuset);
+    CPU_SET(target_core, &cpuset);
+
+    if (pthread_setaffinity_np(thread, sizeof(cpu_set_t), &cpuset) != 0) {
+        // Silently ignore affinity setting failures - not critical
+        // fprintf(stderr, "Warning: Failed to set CPU affinity for thread\n");
+    }
+}
+
 frame_buffer_t *frame_buffer_init() {
     frame_buffer_t *fb = malloc(sizeof(frame_buffer_t));
     if (!fb) return NULL;
@@ -252,6 +289,7 @@ void handle_tunnel_request(SSL *ssl, const char *request_id, int debug, const ch
 
         pthread_t thread;
         pthread_create(&thread, NULL, forward_ws_to_ssh_server, thread_args);
+        set_thread_cpu_affinity(thread);  // Distribute thread across CPU cores
         pthread_detach(thread);
     }
 }

wssshtools/tunnel.h

@@ -78,4 +78,8 @@ void cleanup_tunnel(int debug);
 int reconnect_websocket(tunnel_t *tunnel, const char *wssshd_host, int wssshd_port, const char *client_id, const char *request_id, int debug);
 int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id, int local_port, int debug, int use_buffer);
 
+// CPU affinity functions
+void init_cpu_affinity(void);
+void set_thread_cpu_affinity(pthread_t thread);
+
 #endif // TUNNEL_H
\ No newline at end of file

wssshtools/wssshc.c

@@ -907,6 +907,9 @@ int main(int argc, char *argv[]) {
         .debug = 0
     };
 
+    // Initialize CPU affinity system for multi-core utilization
+    init_cpu_affinity();
+
     pthread_mutex_init(&tunnel_mutex, NULL);
 
     // Set up signal handler for SIGINT