Mac: app mode loader (shim).

chrome/app/app_mode_loader_mac.mm

+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// On Mac, shortcuts can't have command-line arguments. Instead, produce small
+// app bundles which locate the Chromium framework and load it, passing the
+// appropriate data. This is the code for such an app bundle. It should be kept
+// minimal and do as little work as possible (with as much work done on
+// framework side as possible).
+
+#include <dlfcn.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <CoreFoundation/CoreFoundation.h>
+#import <Foundation/Foundation.h>
+
+#include "chrome/common/app_mode_common_mac.h"
+
+namespace {
+
+// Checks that condition |x| is true. If not, outputs |msg| (together with
+// source filename and line number) and exits.
+#define CHECK_MSG(x, msg) if (!(x)) check_msg_helper(__FILE__, __LINE__, msg);
+void check_msg_helper(const char* file, int line, const char* msg) {
+  fprintf(stderr, "%s (%d): %s\n", file, line, msg);
+  exit(1);
+}
+
+// Converts an NSString to a UTF8 C string (which is allocated, and may be freed
+// using |free()|). If |s| is nil or can't produce such a string, this returns
+// |NULL|.
+char* NSStringToUTF8CString(NSString* s) {
+  CHECK_MSG([s isKindOfClass:[NSString class]], "expected an NSString");
+  const char* cstring = [s UTF8String];
+  return cstring ? strdup(cstring) : NULL;
+}
+
+// Converts an NSString to a file-system representation C string (which is
+// allocated, and may be freed using |free()|). If |s| is nil or can't produce
+// such a string, this returns |NULL|.
+char* NSStringToFSCString(NSString* s) {
+  CHECK_MSG([s isKindOfClass:[NSString class]], "expected an NSString");
+  const char* cstring = [s fileSystemRepresentation];
+  return cstring ? strdup(cstring) : NULL;
+}
+
+}  // namespace
+
+__attribute__((visibility("default")))
+int main(int argc, char** argv) {
+  app_mode::ChromeAppModeInfo info;
+  info.major_version = 0;  // v0.1
+  info.minor_version = 1;
+  info.argc = argc;
+  info.argv = argv;
+
+  // The Cocoa APIs are a bit more convenient; for this an autorelease pool is
+  // needed.
+  NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
+
+  // Get the browser bundle path.
+  // TODO(viettrungluu): more fun
+  NSString* cr_bundle_path =
+      [(NSString*)CFPreferencesCopyAppValue(
+          app_mode::kLastRunAppBundlePathPrefsKey,
+          app_mode::kAppPrefsID) autorelease];
+  CHECK_MSG(cr_bundle_path, "couldn't get browser bundle path");
+
+  // Get the browser bundle.
+  NSBundle* cr_bundle = [NSBundle bundleWithPath:cr_bundle_path];
+  CHECK_MSG(cr_bundle, "couldn't get browser bundle");
+
+  // Get the current browser version.
+  NSString* cr_version =
+      [cr_bundle objectForInfoDictionaryKey:@"CFBundleShortVersionString"];
+  CHECK_MSG(cr_version, "couldn't get browser version");
+
+  // Get the current browser versioned directory.
+  NSArray* cr_versioned_path_components =
+      [NSArray arrayWithObjects:cr_bundle_path,
+                                @"Contents",
+                                @"Versions",
+                                cr_version,
+                                nil];
+  NSString* cr_versioned_path =
+      [[NSString pathWithComponents:cr_versioned_path_components]
+          stringByStandardizingPath];
+  CHECK_MSG(cr_versioned_path, "couldn't get browser versioned path");
+  // And copy it, since |cr_versioned_path| will go away with the pool.
+  info.chrome_versioned_path = NSStringToFSCString(cr_versioned_path);
+
+  // Get the current main bundle, i.e., that of the app loader that's running.
+  NSBundle* app_bundle = [NSBundle mainBundle];
+  CHECK_MSG(app_bundle, "couldn't get loader bundle");
+  // Optional, so okay if it's NULL.
+  info.app_mode_bundle_path = NSStringToFSCString([app_bundle bundlePath]);
+
+  // Read information about the this app shortcut from the Info.plist.
+  // Don't check for null-ness on optional items.
+  NSDictionary* info_plist = [app_bundle infoDictionary];
+  CHECK_MSG(info_plist, "couldn't get loader Info.plist");
+
+  info.app_mode_id = NSStringToUTF8CString(
+      [info_plist objectForKey:@"CrAppModeShortcutID"]);
+  CHECK_MSG(info.app_mode_id, "couldn't get app shortcut ID");
+
+  info.app_mode_short_name = NSStringToUTF8CString(
+      [info_plist objectForKey:@"CrAppModeShortcutShortName"]);
+
+  info.app_mode_name = NSStringToUTF8CString(
+      [info_plist objectForKey:@"CrAppModeShortcutName"]);
+
+  info.app_mode_url = NSStringToUTF8CString(
+      [info_plist objectForKey:@"CrAppModeShortcutURL"]);
+  CHECK_MSG(info.app_mode_url, "couldn't get app shortcut URL");
+
+  // Get the framework path.
+  NSString* cr_bundle_exe =
+      [cr_bundle objectForInfoDictionaryKey:@"CFBundleExecutable"];
+  NSString* cr_framework_path =
+      [cr_versioned_path stringByAppendingPathComponent:
+          [cr_bundle_exe stringByAppendingString:@" Framework.framework"]];
+  cr_framework_path =
+      [cr_framework_path stringByAppendingPathComponent:
+          [cr_bundle_exe stringByAppendingString:@" Framework"]];
+
+  // Open the framework.
+  void* cr_dylib = dlopen([cr_framework_path fileSystemRepresentation],
+                          RTLD_LAZY);
+  CHECK_MSG(cr_dylib, "couldn't load framework");
+
+  // Drain the pool as late as possible.
+  [pool drain];
+
+  typedef int (*StartFun)(const app_mode::ChromeAppModeInfo*);
+  StartFun ChromeAppModeStart = (StartFun)dlsym(cr_dylib, "ChromeAppModeStart");
+  CHECK_MSG(ChromeAppModeStart, "couldn't get entry point");
+
+  // Exit instead of returning to avoid the the removal of |main()| from stack
+  // backtraces under tail call optimization.
+  int rv = ChromeAppModeStart(&info);
+  exit(rv);
+}