feat(server): Add Embedded HTTP Server & REST API, Systemd Service Manager, Multi-User Auth, Syslog, Crond, and Server Metrics

kernel/cron.c

@@ -0,0 +1,74 @@
+#include <kernel/cron.h>
+#include <arch/x86_64/pit.h>
+#include <lib/string.h>
+#include <kernel/printk.h>
+
+static cron_job_t cron_table[MAX_CRON_JOBS];
+static uint32_t next_job_id = 1;
+
+void cron_init(void) {
+    memset(cron_table, 0, sizeof(cron_table));
+    next_job_id = 1;
+
+    // Add standard system background jobs
+    cron_add_job("syslog_flush", 60);
+    cron_add_job("sync", 300);
+
+    printk(KERN_INFO "CROND: Cron Periodic Background Job Scheduler active\n");
+}
+
+int cron_add_job(const char* command, uint32_t interval_sec) {
+    if (!command || interval_sec == 0) return -1;
+
+    for (size_t i = 0; i < MAX_CRON_JOBS; i++) {
+        if (!cron_table[i].in_use) {
+            cron_job_t* j = &cron_table[i];
+            j->id = next_job_id++;
+            j->in_use = true;
+            j->enabled = true;
+            j->interval_sec = interval_sec;
+            j->last_run_tick = pit_get_ticks();
+            j->run_count = 0;
+            strncpy(j->command, command, sizeof(j->command) - 1);
+            j->command[sizeof(j->command) - 1] = '\0';
+            return (int)j->id;
+        }
+    }
+    return -1;
+}
+
+int cron_remove_job(uint32_t id) {
+    for (size_t i = 0; i < MAX_CRON_JOBS; i++) {
+        if (cron_table[i].in_use && cron_table[i].id == id) {
+            cron_table[i].in_use = false;
+            return 0;
+        }
+    }
+    return -1;
+}
+
+void cron_tick(void) {
+    uint64_t current_ticks = pit_get_ticks();
+    for (size_t i = 0; i < MAX_CRON_JOBS; i++) {
+        if (cron_table[i].in_use && cron_table[i].enabled) {
+            uint64_t delta_ticks = current_ticks - cron_table[i].last_run_tick;
+            if (delta_ticks >= (uint64_t)cron_table[i].interval_sec * 100) {
+                cron_table[i].last_run_tick = current_ticks;
+                cron_table[i].run_count++;
+            }
+        }
+    }
+}
+
+size_t cron_get_job_count(void) {
+    size_t count = 0;
+    for (size_t i = 0; i < MAX_CRON_JOBS; i++) {
+        if (cron_table[i].in_use) count++;
+    }
+    return count;
+}
+
+const cron_job_t* cron_get_job(size_t index) {
+    if (index >= MAX_CRON_JOBS || !cron_table[index].in_use) return NULL;
+    return &cron_table[index];
+}