Exit handling on iOS

zerocc2014 · Oct 25, 2017 · afb6b5d · afb6b5d
1 parent 9ba95aa
commit afb6b5d
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Showing 8 changed files with 46 additions and 9 deletions.
diff --git a/app/AppDelegate.h b/app/AppDelegate.h
@@ -11,6 +11,6 @@
 
 @property (strong, nonatomic) UIWindow *window;
 
-
 @end
 
+extern NSString *const ISHExitedNotification;
diff --git a/app/AppDelegate.m b/app/AppDelegate.m
@@ -14,6 +14,10 @@ @interface AppDelegate ()
 
 @end
 
+static void ios_handle_exit(int code) {
+    [[NSNotificationCenter defaultCenter] postNotificationName:ISHExitedNotification object:nil];
+}
+
 @implementation AppDelegate
 
 - (int)startThings {
@@ -31,6 +35,7 @@ - (int)startThings {
     err = create_stdio(ios_tty_driver);
     if (err < 0)
         return err;
+    exit_hook = ios_handle_exit;
     start_thread(current);
     return 0;
 }
@@ -72,3 +77,5 @@ - (void)applicationWillTerminate:(UIApplication *)application {
 
 
 @end
+
+NSString *const ISHExitedNotification = @"ISHExitedNotification";
diff --git a/app/TerminalViewController.m b/app/TerminalViewController.m
@@ -6,6 +6,7 @@
 //
 
 #import "TerminalViewController.h"
+#import "AppDelegate.h"
 
 @interface TerminalViewController ()
 
@@ -30,8 +31,15 @@ - (void)viewDidLoad {
                     forKeyPath:@"content"
                        options:NSKeyValueObservingOptionInitial
                        context:NULL];
+    [[NSNotificationCenter defaultCenter] addObserver:self
+                                             selector:@selector(ishExited)
+                                                 name:ISHExitedNotification
+                                               object:nil];
 }
 
+- (void)ishExited:(NSNotification *)notification {
+    NSLog(@"exit");
+}
 
 - (void)didReceiveMemoryWarning {
     [super didReceiveMemoryWarning];

diff --git a/kernel/exit.c b/kernel/exit.c
@@ -1,10 +1,9 @@
 #include <pthread.h>
 #include "kernel/calls.h"
 
+void (*exit_hook)(int code) = NULL;
+
 noreturn void do_exit(int status) {
-    if (current->pid == 1) {
-        exit(status >> 8);
-    }
     lock(current->parent);
     current->exit_code = status;
     current->zombie = true;
@@ -15,6 +14,20 @@ noreturn void do_exit(int status) {
     notify(current, vfork_done);
     unlock(current);
 
+    if (current->pid == 1) { 
+        // brutally murder everything
+        // which will leave everything in an inconsistent state. I will solve this problem later.
+        big_lock(pids);
+        for (int i = 2; i < MAX_PID; i++) {
+            struct process *proc = pid_get_proc(i);
+            if (proc != NULL)
+                pthread_kill(proc->thread, SIGKILL);
+        }
+        big_unlock(pids);
+
+        if (exit_hook != NULL)
+            exit_hook(status);
+    }
     pthread_exit(NULL);
 }
 

diff --git a/kernel/init.c b/kernel/init.c
@@ -27,6 +27,7 @@ int create_init_process(const char *program, char *const argv[], char *const env
 
     current = process_create();
     current->cpu.mem = mem_new();
+    current->parent = current;
     current->ppid = 1;
     current->uid = current->gid = 0;
     current->root = generic_open("/", O_RDONLY_, 0);

diff --git a/kernel/process.c b/kernel/process.c
@@ -7,7 +7,6 @@
 
 __thread struct process *current;
 
-#define MAX_PID (1 << 10) // oughta be enough
 static struct pid pids[MAX_PID + 1] = {};
 pthread_mutex_t pids_lock = PTHREAD_MUTEX_INITIALIZER;
 
@@ -70,12 +69,12 @@ void process_destroy(struct process *proc) {
     free(proc);
 }
 
-void (*process_run_func)() = NULL;
+void (*process_run_hook)() = NULL;
 
 static void *process_run(void *proc) {
     current = proc;
-    if (process_run_func)
-        process_run_func();
+    if (process_run_hook)
+        process_run_hook();
     else
         cpu_run(&current->cpu);
     assert(false);

diff --git a/kernel/process.h b/kernel/process.h
@@ -75,9 +75,13 @@ struct pid *pid_get(dword_t pid);
 struct process *pid_get_proc(dword_t pid);
 extern pthread_mutex_t pids_lock;
 
+#define MAX_PID (1 << 10) // oughta be enough
+
 // When a thread is created to run a new process, this function is used.
-extern void (*run_process_func)(void);
+extern void (*process_run_hook)(void);
 // TODO document
 void start_thread(struct process *proc);
 
+extern void (*exit_hook)(int code);
+
 #endif
diff --git a/xX_main_Xx.h b/xX_main_Xx.h
@@ -2,6 +2,10 @@
 #include "kernel/init.h"
 #include "kernel/fs.h"
 
+static void exit_handler(int code) {
+    exit(code >> 8);
+}
+
 // this function parses command line arguments and initializes global
 // data structures. thanks programming discussions discord server for the name.
 // https://discord.gg/9zT7NHP
@@ -33,5 +37,6 @@ static inline int xX_main_Xx(int argc, char *const argv[]) {
     err = create_stdio(real_tty_driver);
     if (err < 0)
         return err;
+    exit_hook = exit_handler;
     return 0;
 }
Original file line number	Diff line number	Diff line change
Expand Up		@@ -11,6 +11,6 @@

		@property (strong, nonatomic) UIWindow *window;


		@end

		extern NSString *const ISHExitedNotification;