Message passing / mail system

libmsl/init/__premain.c

@@ -16,8 +16,12 @@ static void clear_bss (void) {
 
 void __premain (void) {
   clear_bss ();
+
   liballoc_init ();
+
   app_main ();
+
   liballoc_deinit ();
+
   quit ();
 }

libmsl/m/system.c

@@ -52,3 +52,15 @@ int read (const char* path, size_t off, uint8_t* buffer, size_t size) {
 int describe (const char* path, struct fs_desc_buffer* desc) {
   return (int)do_syscall (SYS_DESCRIBE, path, desc);
 }
+
+int mail_send (int pgid, void* mesg, size_t mesg_size) {
+  return (int)do_syscall (SYS_MAIL_SEND, pgid, mesg, mesg_size);
+}
+
+int mail_receive (void* mesg, size_t mesg_size) {
+  return (int)do_syscall (SYS_MAIL_RECEIVE, mesg, mesg_size);
+}
+
+int get_procgroup (int pid) { return (int)do_syscall (SYS_GET_PROCGROUP, pid); }
+
+int get_exec_pid (void) { return (int)do_syscall (SYS_GET_EXEC_PID, 0); }

libmsl/m/system.h

@@ -65,4 +65,16 @@ int read (const char* path, size_t off, uint8_t* buffer, size_t size);
 /* describe a file */
 int describe (const char* path, struct fs_desc_buffer* desc);
 
+/* send a message to a procgroup's mail */
+int mail_send (int pgid, void* mesg, size_t mesg_size);
+
+/* receive a message from mail */
+int mail_receive (void* mesg, size_t mesg_size);
+
+/* get procgroup id of a perticular process */
+int get_procgroup (int pid);
+
+/* get PID of process, which exec'ed the current process */
+int get_exec_pid (void);
+
 #endif // _LIBMSL_M_SYSTEM_H