app_main.cpp revision d53afd2b05f428fcce5695770c04d6cb6fba7aca 
1/*
2 * Main entry of app process.
3 *
4 * Starts the interpreted runtime, then starts up the application.
5 *
6 */
7
8#define LOG_TAG "appproc"
9
10#include <binder/IPCThreadState.h>
11#include <binder/ProcessState.h>
12#include <utils/Log.h>
13#include <cutils/process_name.h>
14#include <cutils/memory.h>
15#include <cutils/trace.h>
16#include <android_runtime/AndroidRuntime.h>
17
18#include <stdlib.h>
19#include <stdio.h>
20#include <unistd.h>
21
22namespace android {
23
24void app_usage()
25{
26    fprintf(stderr,
27        "Usage: app_process [java-options] cmd-dir start-class-name [options]\n");
28}
29
30class AppRuntime : public AndroidRuntime
31{
32public:
33    AppRuntime()
34        : mParentDir(NULL)
35        , mClassName(NULL)
36        , mClass(NULL)
37        , mArgC(0)
38        , mArgV(NULL)
39    {
40    }
41
42#if 0
43    // this appears to be unused
44    const char* getParentDir() const
45    {
46        return mParentDir;
47    }
48#endif
49
50    const char* getClassName() const
51    {
52        return mClassName;
53    }
54
55    virtual void onVmCreated(JNIEnv* env)
56    {
57        if (mClassName == NULL) {
58            return; // Zygote. Nothing to do here.
59        }
60
61        /*
62         * This is a little awkward because the JNI FindClass call uses the
63         * class loader associated with the native method we're executing in.
64         * If called in onStarted (from RuntimeInit.finishInit because we're
65         * launching "am", for example), FindClass would see that we're calling
66         * from a boot class' native method, and so wouldn't look for the class
67         * we're trying to look up in CLASSPATH. Unfortunately it needs to,
68         * because the "am" classes are not boot classes.
69         *
70         * The easiest fix is to call FindClass here, early on before we start
71         * executing boot class Java code and thereby deny ourselves access to
72         * non-boot classes.
73         */
74        char* slashClassName = toSlashClassName(mClassName);
75        mClass = env->FindClass(slashClassName);
76        if (mClass == NULL) {
77            ALOGE("ERROR: could not find class '%s'\n", mClassName);
78        }
79        free(slashClassName);
80
81        mClass = reinterpret_cast<jclass>(env->NewGlobalRef(mClass));
82    }
83
84    virtual void onStarted()
85    {
86        sp<ProcessState> proc = ProcessState::self();
87        ALOGV("App process: starting thread pool.\n");
88        proc->startThreadPool();
89
90        AndroidRuntime* ar = AndroidRuntime::getRuntime();
91        ar->callMain(mClassName, mClass, mArgC, mArgV);
92
93        IPCThreadState::self()->stopProcess();
94    }
95
96    virtual void onZygoteInit()
97    {
98        // Re-enable tracing now that we're no longer in Zygote.
99        atrace_set_tracing_enabled(true);
100
101        sp<ProcessState> proc = ProcessState::self();
102        ALOGV("App process: starting thread pool.\n");
103        proc->startThreadPool();
104    }
105
106    virtual void onExit(int code)
107    {
108        if (mClassName == NULL) {
109            // if zygote
110            IPCThreadState::self()->stopProcess();
111        }
112
113        AndroidRuntime::onExit(code);
114    }
115
116
117    const char* mParentDir;
118    const char* mClassName;
119    jclass mClass;
120    int mArgC;
121    const char* const* mArgV;
122};
123
124}
125
126using namespace android;
127
128/*
129 * sets argv0 to as much of newArgv0 as will fit
130 */
131static void setArgv0(const char *argv0, const char *newArgv0)
132{
133    strlcpy(const_cast<char *>(argv0), newArgv0, strlen(argv0));
134}
135
136int main(int argc, char* const argv[])
137{
138    // These are global variables in ProcessState.cpp
139    mArgC = argc;
140    mArgV = argv;
141
142    mArgLen = 0;
143    for (int i=0; i<argc; i++) {
144        mArgLen += strlen(argv[i]) + 1;
145    }
146    mArgLen--;
147
148    AppRuntime runtime;
149    const char* argv0 = argv[0];
150
151    // Process command line arguments
152    // ignore argv[0]
153    argc--;
154    argv++;
155
156    // Everything up to '--' or first non '-' arg goes to the vm
157
158    int i = runtime.addVmArguments(argc, argv);
159
160    // Parse runtime arguments.  Stop at first unrecognized option.
161    bool zygote = false;
162    bool startSystemServer = false;
163    bool application = false;
164    const char* parentDir = NULL;
165    const char* niceName = NULL;
166    const char* className = NULL;
167    while (i < argc) {
168        const char* arg = argv[i++];
169        if (!parentDir) {
170            parentDir = arg;
171        } else if (strcmp(arg, "--zygote") == 0) {
172            zygote = true;
173            niceName = "zygote";
174        } else if (strcmp(arg, "--start-system-server") == 0) {
175            startSystemServer = true;
176        } else if (strcmp(arg, "--application") == 0) {
177            application = true;
178        } else if (strncmp(arg, "--nice-name=", 12) == 0) {
179            niceName = arg + 12;
180        } else {
181            className = arg;
182            break;
183        }
184    }
185
186    if (niceName && *niceName) {
187        setArgv0(argv0, niceName);
188        set_process_name(niceName);
189    }
190
191    runtime.mParentDir = parentDir;
192
193    if (zygote) {
194        runtime.start("com.android.internal.os.ZygoteInit",
195                startSystemServer ? "start-system-server" : "");
196    } else if (className) {
197        // Remainder of args get passed to startup class main()
198        runtime.mClassName = className;
199        runtime.mArgC = argc - i;
200        runtime.mArgV = argv + i;
201        runtime.start("com.android.internal.os.RuntimeInit",
202                application ? "application" : "tool");
203    } else {
204        fprintf(stderr, "Error: no class name or --zygote supplied.\n");
205        app_usage();
206        LOG_ALWAYS_FATAL("app_process: no class name or --zygote supplied.");
207        return 10;
208    }
209}
210