1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_TEST_MULTIPROCESS_TEST_H_ 6 #define BASE_TEST_MULTIPROCESS_TEST_H_ 7 8 #include <string> 9 10 #include "base/basictypes.h" 11 #include "base/process/launch.h" 12 #include "base/process/process_handle.h" 13 #include "build/build_config.h" 14 #include "testing/platform_test.h" 15 16 namespace base { 17 18 class CommandLine; 19 20 // Helpers to spawn a child for a multiprocess test and execute a designated 21 // function. Use these when you already have another base class for your test 22 // fixture, but you want (some) of your tests to be multiprocess (otherwise you 23 // may just want to derive your fixture from |MultiProcessTest|, below). 24 // 25 // Use these helpers as follows: 26 // 27 // TEST_F(MyTest, ATest) { 28 // CommandLine command_line( 29 // base::GetMultiProcessTestChildBaseCommandLine()); 30 // // Maybe add our own switches to |command_line|.... 31 // 32 // LaunchOptions options; 33 // // Maybe set some options (e.g., |start_hidden| on Windows).... 34 // 35 // // Start a child process and run |a_test_func|. 36 // base::ProcessHandle test_child_handle = 37 // base::SpawnMultiProcessTestChild("a_test_func", command_line, 38 // options); 39 // 40 // // Do stuff involving |test_child_handle| and the child process.... 41 // 42 // int rv = -1; 43 // ASSERT_TRUE(base::WaitForExitCodeWithTimeout( 44 // test_child_handle, &rv, TestTimeouts::action_timeout())); 45 // base::CloseProcessHandle(test_child_handle); 46 // EXPECT_EQ(0, rv); 47 // } 48 // 49 // // Note: |MULTIPROCESS_TEST_MAIN()| is defined in 50 // // testing/multi_process_function_list.h. 51 // MULTIPROCESS_TEST_MAIN(a_test_func) { 52 // // Code here runs in a child process.... 53 // return 0; 54 // } 55 56 // Spawns a child process and executes the function |procname| declared using 57 // |MULTIPROCESS_TEST_MAIN()| or |MULTIPROCESS_TEST_MAIN_WITH_SETUP()|. 58 // |command_line| should be as provided by 59 // |GetMultiProcessTestChildBaseCommandLine()| (below), possibly with arguments 60 // added. Note: On Windows, you probably want to set |options.start_hidden|. 61 ProcessHandle SpawnMultiProcessTestChild( 62 const std::string& procname, 63 const CommandLine& command_line, 64 const LaunchOptions& options); 65 66 // Gets the base command line for |SpawnMultiProcessTestChild()|. To this, you 67 // may add any flags needed for your child process. 68 CommandLine GetMultiProcessTestChildBaseCommandLine(); 69 70 // MultiProcessTest ------------------------------------------------------------ 71 72 // A MultiProcessTest is a test class which makes it easier to 73 // write a test which requires code running out of process. 74 // 75 // To create a multiprocess test simply follow these steps: 76 // 77 // 1) Derive your test from MultiProcessTest. Example: 78 // 79 // class MyTest : public MultiProcessTest { 80 // }; 81 // 82 // TEST_F(MyTest, TestCaseName) { 83 // ... 84 // } 85 // 86 // 2) Create a mainline function for the child processes and include 87 // testing/multiprocess_func_list.h. 88 // See the declaration of the MULTIPROCESS_TEST_MAIN macro 89 // in that file for an example. 90 // 3) Call SpawnChild("foo"), where "foo" is the name of 91 // the function you wish to run in the child processes. 92 // That's it! 93 class MultiProcessTest : public PlatformTest { 94 public: 95 MultiProcessTest(); 96 97 protected: 98 // Run a child process. 99 // 'procname' is the name of a function which the child will 100 // execute. It must be exported from this library in order to 101 // run. 102 // 103 // Example signature: 104 // extern "C" int __declspec(dllexport) FooBar() { 105 // // do client work here 106 // } 107 // 108 // Returns the handle to the child, or NULL on failure 109 ProcessHandle SpawnChild(const std::string& procname); 110 111 // Run a child process using the given launch options. 112 // 113 // Note: On Windows, you probably want to set |options.start_hidden|. 114 ProcessHandle SpawnChildWithOptions(const std::string& procname, 115 const LaunchOptions& options); 116 117 // Set up the command line used to spawn the child process. 118 // Override this to add things to the command line (calling this first in the 119 // override). 120 // Note that currently some tests rely on this providing a full command line, 121 // which they then use directly with |LaunchProcess()|. 122 // TODO(viettrungluu): Remove this and add a virtual 123 // |ModifyChildCommandLine()|; make the two divergent uses more sane. 124 virtual CommandLine MakeCmdLine(const std::string& procname); 125 126 private: 127 DISALLOW_COPY_AND_ASSIGN(MultiProcessTest); 128 }; 129 130 } // namespace base 131 132 #endif // BASE_TEST_MULTIPROCESS_TEST_H_ 133