Make the iOS terminal look like a pty

Also make the terminal and session owned by TerminalViewController. This is in preparation for scene support. Co-authored-by: Noah Peeters <noah.peeters@icloud.com>
zerocc2014 · Oct 28, 2019 · 6c906ac · 6c906ac
1 parent 32ae8bc
commit 6c906ac
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Showing 10 changed files with 186 additions and 130 deletions.
diff --git a/app/AppDelegate.m b/app/AppDelegate.m
@@ -15,14 +15,12 @@
 #import "UserPreferences.h"
 #include "kernel/init.h"
 #include "kernel/calls.h"
-#include "fs/path.h"
 #include "fs/dyndev.h"
 #include "fs/devices.h"
+#include "fs/path.h"
 
 @interface AppDelegate ()
 
-@property int sessionPid;
-
 @property BOOL exiting;
 
 @end
@@ -158,73 +156,32 @@ - (int)startThings {
     NSString *sockTmp = [NSTemporaryDirectory() stringByAppendingString:@"ishsock"];
     sock_tmp_prefix = strdup(sockTmp.UTF8String);
 
-    tty_drivers[TTY_CONSOLE_MAJOR] = &ios_tty_driver;
+    tty_drivers[TTY_CONSOLE_MAJOR] = &ios_console_driver;
     set_console_device(TTY_CONSOLE_MAJOR, 1);
-    err = create_stdio("/dev/console");
+    err = create_stdio("/dev/console", TTY_CONSOLE_MAJOR, 1);
     if (err < 0)
         return err;
 
     NSArray<NSString *> *command;
     command = UserPreferences.shared.bootCommand;
     NSLog(@"%@", command);
     char argv[4096];
-    [self convertCommand:command toArgs:argv limitSize:sizeof(argv)];
+    [Terminal convertCommand:command toArgs:argv limitSize:sizeof(argv)];
     const char *envp = "TERM=xterm-256color\0";
     err = sys_execve(argv, argv, envp);
     if (err < 0)
         return err;
     task_start(current);
 
-    err = [self startSession];
-    if (err < 0)
-        return err;
-
-    return 0;
-}
-
-- (int)startSession {
-    int err = become_new_init_child();
-    if (err < 0)
-        return err;
-    err = create_stdio("/dev/tty7");
-    if (err < 0)
-        return err;
-    char argv[4096];
-    [self convertCommand:UserPreferences.shared.launchCommand toArgs:argv limitSize:sizeof(argv)];
-    const char *envp = "TERM=xterm-256color\0";
-    err = sys_execve(argv, argv, envp);
-    if (err < 0)
-        return err;
-    self.sessionPid = current->pid;
-    task_start(current);
     return 0;
 }
 
-- (void)convertCommand:(NSArray<NSString *> *)command toArgs:(char *)argv limitSize:(size_t)maxSize {
-    char *p = argv;
-    for (NSString *cmd in command) {
-        const char *c = cmd.UTF8String;
-        // Save space for the final NUL byte in argv
-        while (p < argv + maxSize - 1 && (*p++ = *c++));
-        // If we reach the end of the buffer, the last string still needs to be
-        // NUL terminated
-        *p = '\0';
-    }
-    // Add the final NUL byte to argv
-    *++p = '\0';
-}
-
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
     // get the network permissions popup to appear on chinese devices
     [[NSURLSession.sharedSession dataTaskWithURL:[NSURL URLWithString:@"http://captive.apple.com"]] resume];
 
     [UserPreferences.shared addObserver:self forKeyPath:@"shouldDisableDimming" options:NSKeyValueObservingOptionInitial context:nil];
 
-    [NSNotificationCenter.defaultCenter addObserver:self
-                                           selector:@selector(processExited:)
-                                               name:ProcessExitedNotification
-                                             object:nil];
-
     int err = [self startThings];
     if (err < 0) {
         NSString *message = [NSString stringWithFormat:@"could not initialize"];
@@ -241,13 +198,6 @@ - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(N
     UIApplication.sharedApplication.idleTimerDisabled = UserPreferences.shared.shouldDisableDimming;
 }
 
-- (void)processExited:(NSNotification *)notif {
-    int pid = [notif.userInfo[@"pid"] intValue];
-    if (pid == self.sessionPid) {
-        [self startSession];
-    }
-}
-
 - (void)showMessage:(NSString *)message subtitle:(NSString *)subtitle fatal:(BOOL)fatal {
     dispatch_async(dispatch_get_main_queue(), ^{
         UIAlertController *alert = [UIAlertController alertControllerWithTitle:message message:subtitle preferredStyle:UIAlertControllerStyleAlert];

diff --git a/app/Terminal.h b/app/Terminal.h
@@ -8,18 +8,27 @@
 #import <UIKit/UIKit.h>
 #import <WebKit/WebKit.h>
 
+struct tty;
+
 @interface Terminal : NSObject
 
 + (Terminal *)terminalWithType:(int)type number:(int)number;
+// Returns a strong struct tty and a Terminal that has a weak reference to the same tty
++ (Terminal *)createPseudoTerminal:(struct tty **)tty;
+
++ (void)convertCommand:(NSArray<NSString *> *)command toArgs:(char *)argv limitSize:(size_t)maxSize;
 
 - (int)write:(const void *)buf length:(size_t)len;
 - (void)sendInput:(const char *)buf length:(size_t)len;
 
 - (NSString *)arrow:(char)direction;
 
+// Make this terminal no longer be the singleton terminal with its type and number. Will happen eventually if all references go away, but sometimes you want it to happen now.
+- (void)destroy;
+
 @property (readonly) WKWebView *webView;
 @property (nonatomic) BOOL enableVoiceOverAnnounce;
 
 @end
 
-extern struct tty_driver ios_tty_driver;
+extern struct tty_driver ios_console_driver;
diff --git a/app/Terminal.m b/app/Terminal.m
@@ -8,8 +8,11 @@
 #import "Terminal.h"
 #import "DelayedUITask.h"
 #import "UserPreferences.h"
+#include "fs/devices.h"
 #include "fs/tty.h"
 
+extern struct tty_driver ios_pty_driver;
+
 @interface Terminal () <WKScriptMessageHandler>
 
 @property WKWebView *webView;
@@ -22,6 +25,8 @@ @interface Terminal () <WKScriptMessageHandler>
 
 @property BOOL applicationCursor;
 
+@property NSNumber *terminalsKey;
+
 @end
 
 @interface CustomWebView : WKWebView
@@ -34,11 +39,11 @@ - (BOOL)becomeFirstResponder {
 
 @implementation Terminal
 
-static NSMutableDictionary<NSNumber *, Terminal *> *terminals;
+static NSMapTable<NSNumber *, Terminal *> *terminals;
 
 - (instancetype)initWithType:(int)type number:(int)num {
-    NSNumber *key = @(dev_make(type, num));
-    Terminal *terminal = [terminals objectForKey:key];
+    self.terminalsKey = @(dev_make(type, num));
+    Terminal *terminal = [terminals objectForKey:self.terminalsKey];
     if (terminal)
         return terminal;
 
@@ -60,14 +65,23 @@ - (instancetype)initWithType:(int)type number:(int)num {
         [self.webView loadFileURL:xtermHtmlFile allowingReadAccessToURL:xtermHtmlFile];
         [self _addPreferenceObservers];
 
-        [terminals setObject:self forKey:key];
+        [terminals setObject:self forKey:self.terminalsKey];
     }
     return self;
 }
 
++ (Terminal *)createPseudoTerminal:(struct tty **)tty {
+    *tty = pty_open_fake(&ios_pty_driver);
+    if (IS_ERR(*tty))
+        return nil;
+    return (__bridge Terminal *) (*tty)->data;
+}
+
 - (void)setTty:(struct tty *)tty {
     _tty = tty;
-    [self syncWindowSize];
+    dispatch_async(dispatch_get_main_queue(), ^{
+        [self syncWindowSize];
+    });
 }
 
 - (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message {
@@ -115,6 +129,8 @@ - (int)write:(const void *)buf length:(size_t)len {
 }
 
 - (void)sendInput:(const char *)buf length:(size_t)len {
+    if (self.tty == NULL)
+        return;
     tty_input(self.tty, buf, len, 0);
     [self.webView evaluateJavaScript:@"exports.setUserGesture()" completionHandler:nil];
     [self.scrollToBottomTask schedule];
@@ -240,18 +256,35 @@ - (void)refresh {
     [self.webView evaluateJavaScript:jsToEvaluate completionHandler:nil];
 }
 
++ (void)convertCommand:(NSArray<NSString *> *)command toArgs:(char *)argv limitSize:(size_t)maxSize {
+    char *p = argv;
+    for (NSString *cmd in command) {
+        const char *c = cmd.UTF8String;
+        // Save space for the final NUL byte in argv
+        while (p < argv + maxSize - 1 && (*p++ = *c++));
+        // If we reach the end of the buffer, the last string still needs to be
+        // NUL terminated
+        *p = '\0';
+    }
+    // Add the final NUL byte to argv
+    *++p = '\0';
+}
+
 + (Terminal *)terminalWithType:(int)type number:(int)number {
     return [[Terminal alloc] initWithType:type number:number];
 }
 
+- (void)destroy {
+    [terminals removeObjectForKey:self.terminalsKey];
+}
+
 + (void)initialize {
-    terminals = [NSMutableDictionary new];
+    terminals = [NSMapTable strongToWeakObjectsMapTable];
 }
 
 @end
 
 static int ios_tty_init(struct tty *tty) {
-    tty->refcount++;
     void (^init_block)(void) = ^{
         Terminal *terminal = [Terminal terminalWithType:tty->type number:tty->num];
         tty->data = (void *) CFBridgingRetain(terminal);
@@ -262,27 +295,6 @@ static int ios_tty_init(struct tty *tty) {
     else
         dispatch_sync(dispatch_get_main_queue(), init_block);
 
-    // termios
-    tty->termios.lflags = ISIG_ | ICANON_ | ECHO_ | ECHOE_ | ECHOCTL_;
-    tty->termios.iflags = ICRNL_;
-    tty->termios.oflags = OPOST_ | ONLCR_;
-    tty->termios.cc[VINTR_] = '\x03';
-    tty->termios.cc[VQUIT_] = '\x1c';
-    tty->termios.cc[VERASE_] = '\x7f';
-    tty->termios.cc[VKILL_] = '\x15';
-    tty->termios.cc[VEOF_] = '\x04';
-    tty->termios.cc[VTIME_] = 0;
-    tty->termios.cc[VMIN_] = 1;
-    tty->termios.cc[VSTART_] = '\x11';
-    tty->termios.cc[VSTOP_] = '\x13';
-    tty->termios.cc[VSUSP_] = '\x1a';
-    tty->termios.cc[VEOL_] = 0;
-    tty->termios.cc[VREPRINT_] = '\x12';
-    tty->termios.cc[VDISCARD_] = '\x0f';
-    tty->termios.cc[VWERASE_] = '\x17';
-    tty->termios.cc[VLNEXT_] = '\x16';
-    tty->termios.cc[VEOL2_] = 0;
-
     return 0;
 }
 
@@ -292,12 +304,15 @@ static int ios_tty_write(struct tty *tty, const void *buf, size_t len, bool bloc
 }
 
 static void ios_tty_cleanup(struct tty *tty) {
-    CFBridgingRelease(tty->data);
+    Terminal *terminal = CFBridgingRelease(tty->data);
+    tty->data = NULL;
+    terminal.tty = NULL;
 }
 
 struct tty_driver_ops ios_tty_ops = {
     .init = ios_tty_init,
     .write = ios_tty_write,
     .cleanup = ios_tty_cleanup,
 };
-DEFINE_TTY_DRIVER(ios_tty_driver, &ios_tty_ops, 64);
+DEFINE_TTY_DRIVER(ios_console_driver, &ios_tty_ops, 64);
+struct tty_driver ios_pty_driver = {.ops = &ios_tty_ops};
diff --git a/app/TerminalViewController.m b/app/TerminalViewController.m
@@ -12,6 +12,9 @@
 #import "ArrowBarButton.h"
 #import "UserPreferences.h"
 #import "AboutViewController.h"
+#include "kernel/init.h"
+#include "kernel/task.h"
+#include "kernel/calls.h"
 #include "fs/devices.h"
 
 @interface TerminalViewController () <UIGestureRecognizerDelegate>
@@ -38,13 +41,22 @@ @interface TerminalViewController () <UIGestureRecognizerDelegate>
 @property (weak, nonatomic) IBOutlet UIButton *pasteButton;
 @property (weak, nonatomic) IBOutlet UIButton *hideKeyboardButton;
 
+@property int sessionPid;
+@property (nonatomic) Terminal *sessionTerminal;
+
 @end
 
 @implementation TerminalViewController
 
 - (void)viewDidLoad {
     [super viewDidLoad];
-    self.terminal = [Terminal terminalWithType:TTY_CONSOLE_MAJOR number:7];
+
+    [self startSession];
+    [NSNotificationCenter.defaultCenter addObserver:self
+                                           selector:@selector(processExited:)
+                                               name:ProcessExitedNotification
+                                             object:nil];
+
     [self.termView becomeFirstResponder];
 
     NSNotificationCenter *center = [NSNotificationCenter defaultCenter];
@@ -85,6 +97,43 @@ - (void)viewDidLoad {
     }
 }
 
+- (int)startSession {
+    int err = become_new_init_child();
+    if (err < 0)
+        return err;
+    struct tty *tty;
+    [self.sessionTerminal destroy];
+    self.sessionTerminal = nil;
+    Terminal *terminal = [Terminal createPseudoTerminal:&tty];
+    if (terminal == nil) {
+        NSAssert(IS_ERR(tty), @"tty should be error");
+        return (int) PTR_ERR(tty);
+    }
+    self.sessionTerminal = terminal;
+    NSString *stdioFile = [NSString stringWithFormat:@"/dev/pts/%d", tty->num];
+    err = create_stdio(stdioFile.fileSystemRepresentation, TTY_PSEUDO_SLAVE_MAJOR, tty->num);
+    if (err < 0)
+        return err;
+    tty_release(tty);
+
+    char argv[4096];
+    [Terminal convertCommand:UserPreferences.shared.launchCommand toArgs:argv limitSize:sizeof(argv)];
+    const char *envp = "TERM=xterm-256color\0";
+    err = sys_execve(argv, argv, envp);
+    if (err < 0)
+        return err;
+    self.sessionPid = current->pid;
+    task_start(current);
+    return 0;
+}
+
+- (void)processExited:(NSNotification *)notif {
+    int pid = [notif.userInfo[@"pid"] intValue];
+    if (pid == self.sessionPid) {
+        [self startSession];
+    }
+}
+
 - (void)dealloc {
     @try {
         [[UserPreferences shared] removeObserver:self forKeyPath:@"theme"];
@@ -238,7 +287,10 @@ - (IBAction)pressArrow:(ArrowBarButton *)sender {
 
 - (void)switchTerminal:(UIKeyCommand *)sender {
     unsigned i = (unsigned) sender.input.integerValue;
-    self.terminal = [Terminal terminalWithType:TTY_CONSOLE_MAJOR number:i];
+    if (i == 7)
+        self.terminal = self.sessionTerminal;
+    else
+        self.terminal = [Terminal terminalWithType:TTY_CONSOLE_MAJOR number:i];
 }
 
 - (NSArray<UIKeyCommand *> *)keyCommands {
@@ -260,6 +312,12 @@ - (void)setTerminal:(Terminal *)terminal {
     self.termView.terminal = self.terminal;
 }
 
+- (void)setSessionTerminal:(Terminal *)sessionTerminal {
+    if (_terminal == _sessionTerminal)
+        self.terminal = sessionTerminal;
+    _sessionTerminal = sessionTerminal;
+}
+
 @end
 
 @interface BarView : UIInputView