Message passing / mail system

kernel/syscall/syscall.c

@@ -10,6 +10,7 @@
 #include <m/status.h>
 #include <m/syscall_defs.h>
 #include <mm/pmm.h>
+#include <proc/mail.h>
 #include <proc/mutex.h>
 #include <proc/proc.h>
 #include <proc/procgroup.h>
@@ -171,6 +172,58 @@ DEFINE_SYSCALL (sys_mutex_unlock) {
   return SYSRESULT (ST_OK);
 }
 
+/* int mail_send (int pgid, void* mesg, size_t mesg_size) */
+DEFINE_SYSCALL (sys_mail_send) {
+  int pgid = (int)a1;
+  uintptr_t uvaddr_mesg = a2;
+  size_t mesg_size = (size_t)a3;
+
+  void* mesg = sys_get_user_buffer (proc, uvaddr_mesg, mesg_size);
+
+  if (mesg == NULL)
+    return SYSRESULT (-ST_BAD_ADDRESS_SPACE);
+
+  struct procgroup* procgroup = procgroup_find (pgid);
+
+  if (procgroup == NULL)
+    return SYSRESULT (-ST_NOT_FOUND);
+
+  struct proc_resource* mail_resource = proc_find_resource (procgroup, 1);
+
+  if (mail_resource == NULL)
+    return SYSRESULT (-ST_NOT_FOUND);
+
+  if (proc_mail_send (proc, &mail_resource->u.mail, reschedule_cpu, mesg, mesg_size) ==
+      PROC_NEED_RESCHEDULE) {
+    *reschedule = true;
+  }
+
+  return SYSRESULT (ST_OK);
+}
+
+/* int mail_receive (void* recv_mesg, size_t mesg_size) */
+DEFINE_SYSCALL (sys_mail_receive) {
+  uintptr_t uvaddr_mesg = a1;
+  size_t mesg_size = (size_t)a2;
+
+  void* mesg = sys_get_user_buffer (proc, uvaddr_mesg, mesg_size);
+
+  if (mesg == NULL)
+    return SYSRESULT (-ST_BAD_ADDRESS_SPACE);
+
+  struct proc_resource* mail_resource = proc_find_resource (proc->procgroup, 1);
+
+  if (mail_resource == NULL)
+    return SYSRESULT (-ST_NOT_FOUND);
+
+  if (proc_mail_receive (proc, &mail_resource->u.mail, reschedule_cpu, mesg, mesg_size) ==
+      PROC_NEED_RESCHEDULE) {
+    *reschedule = true;
+  }
+
+  return SYSRESULT (ST_OK);
+}
+
 /* int device_do (int device_id, int cmd, void* a1, void* a2, void* a3, void* a4) */
 DEFINE_SYSCALL (sys_device_do) {
   struct limine_hhdm_response* hhdm = limine_hhdm_request.response;
@@ -255,6 +308,7 @@ DEFINE_SYSCALL (sys_exec) {
     return SYSRESULT (-ST_EXEC_ERROR);
 
   int pid = new->pid;
+  new->exec_pid = proc->pid;
 
   if (proc_register (new, reschedule_cpu) == PROC_NEED_RESCHEDULE)
     *reschedule = true;
@@ -381,6 +435,18 @@ DEFINE_SYSCALL (sys_describe) {
   return SYSRESULT (vfs_describe (proc->procgroup, mountpoint, subpath, desc));
 }
 
+/* int get_procgroup (int pid) */
+DEFINE_SYSCALL (sys_get_procgroup) {
+  int pid = (int)a1;
+
+  struct proc* target_proc = proc_find_pid (pid);
+
+  return SYSRESULT (target_proc->procgroup->pgid);
+}
+
+/* int get_exec_pid (void) */
+DEFINE_SYSCALL (sys_get_exec_pid) { return SYSRESULT (proc->exec_pid); }
+
 static syscall_handler_func_t handler_table[] = {
     [SYS_QUIT] = &sys_quit,
     [SYS_TEST] = &sys_test,
@@ -399,6 +465,10 @@ static syscall_handler_func_t handler_table[] = {
     [SYS_CLOSE] = &sys_close,
     [SYS_READ] = &sys_read,
     [SYS_DESCRIBE] = &sys_describe,
+    [SYS_MAIL_SEND] = &sys_mail_send,
+    [SYS_MAIL_RECEIVE] = &sys_mail_receive,
+    [SYS_GET_PROCGROUP] = &sys_get_procgroup,
+    [SYS_GET_EXEC_PID] = &sys_get_exec_pid,
 };
 
 syscall_handler_func_t syscall_find_handler (int syscall_num) {