apps/Term/jni/termExec.cpp - platform/development - Git at Google

 /*
  * Copyright (C) 2008 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 /*
  * Copyright (C) 2007 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "Exec"

 #include "jni.h"
 #include "utils/Log.h"
 #include "utils/misc.h"
 #include "android_runtime/AndroidRuntime.h"

 #include <sys/types.h>
 #include <sys/ioctl.h>
 #include <sys/wait.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <termios.h>

 static jclass class_fileDescriptor;
 static jfieldID field_fileDescriptor_descriptor;
 static jmethodID method_fileDescriptor_init;


 class String8 {
 public:
     String8() {
         mString = 0;
     }

     ~String8() {
         if (mString) {
             free(mString);
         }
     }

     void set(const char16_t* o, size_t numChars) {
         mString = (char*) malloc(numChars + 1);
         for (size_t i = 0; i < numChars; i++) {
             mString[i] = (char) o[i];
         }
         mString[numChars] = '\0';
     }

     const char* string() {
         return mString;
     }
 private:
     char* mString;
 };

 static int create_subprocess(const char *cmd, const char *arg0, const char *arg1,
     int* pProcessId)
 {
     char *devname;
     int ptm;
     pid_t pid;

     ptm = open("/dev/ptmx", O_RDWR); // | O_NOCTTY);
     if(ptm < 0){
         LOGE("[ cannot open /dev/ptmx - %s ]\n",strerror(errno));
         return -1;
     }
     fcntl(ptm, F_SETFD, FD_CLOEXEC);

     if(grantpt(ptm) || unlockpt(ptm) ||
        ((devname = (char*) ptsname(ptm)) == 0)){
         LOGE("[ trouble with /dev/ptmx - %s ]\n", strerror(errno));
         return -1;
     }

     pid = fork();
     if(pid < 0) {
         LOGE("- fork failed: %s -\n", strerror(errno));
         return -1;
     }

     if(pid == 0){
         close(ptm);

         int pts;

         setsid();

         pts = open(devname, O_RDWR);
         if(pts < 0) exit(-1);

         dup2(pts, 0);
         dup2(pts, 1);
         dup2(pts, 2);

         execl(cmd, cmd, arg0, arg1, NULL);
         exit(-1);
     } else {
         *pProcessId = (int) pid;
         return ptm;
     }
 }


 static jobject android_os_Exec_createSubProcess(JNIEnv *env, jobject clazz,
     jstring cmd, jstring arg0, jstring arg1, jintArray processIdArray)
 {
     const jchar* str = cmd ? env->GetStringCritical(cmd, 0) : 0;
     String8 cmd_8;
     if (str) {
         cmd_8.set(str, env->GetStringLength(cmd));
         env->ReleaseStringCritical(cmd, str);
     }

     str = arg0 ? env->GetStringCritical(arg0, 0) : 0;
     const char* arg0Str = 0;
     String8 arg0_8;
     if (str) {
         arg0_8.set(str, env->GetStringLength(arg0));
         env->ReleaseStringCritical(arg0, str);
         arg0Str = arg0_8.string();
     }

     str = arg1 ? env->GetStringCritical(arg1, 0) : 0;
     const char* arg1Str = 0;
     String8 arg1_8;
     if (str) {
         arg1_8.set(str, env->GetStringLength(arg1));
         env->ReleaseStringCritical(arg1, str);
         arg1Str = arg1_8.string();
     }

     int procId;
     int ptm = create_subprocess(cmd_8.string(), arg0Str, arg1Str, &procId);

     if (processIdArray) {
         int procIdLen = env->GetArrayLength(processIdArray);
         if (procIdLen > 0) {
             jboolean isCopy;

             int* pProcId = (int*) env->GetPrimitiveArrayCritical(processIdArray, &isCopy);
             if (pProcId) {
                 *pProcId = procId;
                 env->ReleasePrimitiveArrayCritical(processIdArray, pProcId, 0);
             }
         }
     }

     jobject result = env->NewObject(class_fileDescriptor, method_fileDescriptor_init);

     if (!result) {
         LOGE("Couldn't create a FileDescriptor.");
     }
     else {
         env->SetIntField(result, field_fileDescriptor_descriptor, ptm);
     }

     return result;
 }


 static void android_os_Exec_setPtyWindowSize(JNIEnv *env, jobject clazz,
     jobject fileDescriptor, jint row, jint col, jint xpixel, jint ypixel)
 {
     int fd;
     struct winsize sz;

     fd = env->GetIntField(fileDescriptor, field_fileDescriptor_descriptor);

     if (env->ExceptionOccurred() != NULL) {
         return;
     }

     sz.ws_row = row;
     sz.ws_col = col;
     sz.ws_xpixel = xpixel;
     sz.ws_ypixel = ypixel;

     ioctl(fd, TIOCSWINSZ, &sz);
 }

 static int android_os_Exec_waitFor(JNIEnv *env, jobject clazz,
     jint procId) {
     int status;
     waitpid(procId, &status, 0);
     int result = 0;
     if (WIFEXITED(status)) {
         result = WEXITSTATUS(status);
     }
     return result;
 }

 static void android_os_Exec_close(JNIEnv *env, jobject clazz, jobject fileDescriptor)
 {
     int fd;
     struct winsize sz;

     fd = env->GetIntField(fileDescriptor, field_fileDescriptor_descriptor);

     if (env->ExceptionOccurred() != NULL) {
         return;
     }

     close(fd);
 }


 static int register_FileDescriptor(JNIEnv *env)
 {
     class_fileDescriptor = env->FindClass("java/io/FileDescriptor");

     if (class_fileDescriptor == NULL) {
         LOGE("Can't find java/io/FileDescriptor");
         return -1;
     }

     field_fileDescriptor_descriptor = env->GetFieldID(class_fileDescriptor, "descriptor", "I");

     if (field_fileDescriptor_descriptor == NULL) {
         LOGE("Can't find FileDescriptor.descriptor");
         return -1;
     }

     method_fileDescriptor_init = env->GetMethodID(class_fileDescriptor, "<init>", "()V");
     if (method_fileDescriptor_init == NULL) {
         LOGE("Can't find FileDescriptor.init");
         return -1;
      }
      return 0;
 }


 static const char *classPathName = "com/android/term/Exec";

 static JNINativeMethod method_table[] = {
     { "createSubprocess", "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;[I)Ljava/io/FileDescriptor;",
         (void*) android_os_Exec_createSubProcess },
     { "setPtyWindowSize", "(Ljava/io/FileDescriptor;IIII)V",
         (void*) android_os_Exec_setPtyWindowSize},
     { "waitFor", "(I)I",
         (void*) android_os_Exec_waitFor},
     { "close", "(Ljava/io/FileDescriptor;)V",
         (void*) android_os_Exec_close}
 };

 /*
  * Register several native methods for one class.
  */
 static int registerNativeMethods(JNIEnv* env, const char* className,
     JNINativeMethod* gMethods, int numMethods)
 {
     jclass clazz;

     clazz = env->FindClass(className);
     if (clazz == NULL) {
         LOGE("Native registration unable to find class '%s'", className);
         return JNI_FALSE;
     }
     if (env->RegisterNatives(clazz, gMethods, numMethods) < 0) {
         LOGE("RegisterNatives failed for '%s'", className);
         return JNI_FALSE;
     }

     return JNI_TRUE;
 }

 /*
  * Register native methods for all classes we know about.
  *
  * returns JNI_TRUE on success.
  */
 static int registerNatives(JNIEnv* env)
 {
   if (!registerNativeMethods(env, classPathName, method_table,
                  sizeof(method_table) / sizeof(method_table[0]))) {
     return JNI_FALSE;
   }

   return JNI_TRUE;
 }


 // ----------------------------------------------------------------------------

 /*
  * This is called by the VM when the shared library is first loaded.
  */

 typedef union {
     JNIEnv* env;
     void* venv;
 } UnionJNIEnvToVoid;

 jint JNI_OnLoad(JavaVM* vm, void* reserved) {
     UnionJNIEnvToVoid uenv;
     uenv.venv = NULL;
     jint result = -1;
     JNIEnv* env = NULL;

     LOGI("JNI_OnLoad");

     if (vm->GetEnv(&uenv.venv, JNI_VERSION_1_4) != JNI_OK) {
         LOGE("ERROR: GetEnv failed");
         goto bail;
     }
     env = uenv.env;

     if ((result = register_FileDescriptor(env)) < 0) {
         LOGE("ERROR: registerFileDescriptor failed");
         goto bail;
     }

     if (registerNatives(env) != JNI_TRUE) {
         LOGE("ERROR: registerNatives failed");
         goto bail;
     }

     result = JNI_VERSION_1_4;

 bail:
     return result;
 }
	/*
	* Copyright (C) 2008 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	/*
	* Copyright (C) 2007 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "Exec"

	#include "jni.h"
	#include "utils/Log.h"
	#include "utils/misc.h"
	#include "android_runtime/AndroidRuntime.h"

	#include <sys/types.h>
	#include <sys/ioctl.h>
	#include <sys/wait.h>
	#include <errno.h>
	#include <fcntl.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <termios.h>

	static jclass class_fileDescriptor;
	static jfieldID field_fileDescriptor_descriptor;
	static jmethodID method_fileDescriptor_init;


	class String8 {
	public:
	String8() {
	mString = 0;
	}

	~String8() {
	if (mString) {
	free(mString);
	}
	}

	void set(const char16_t* o, size_t numChars) {
	mString = (char*) malloc(numChars + 1);
	for (size_t i = 0; i < numChars; i++) {
	mString[i] = (char) o[i];
	}
	mString[numChars] = '\0';
	}

	const char* string() {
	return mString;
	}
	private:
	char* mString;
	};

	static int create_subprocess(const char cmd, const char arg0, const char *arg1,
	int* pProcessId)
	{
	char *devname;
	int ptm;
	pid_t pid;

	ptm = open("/dev/ptmx", O_RDWR); // \| O_NOCTTY);
	if(ptm < 0){
	LOGE("[ cannot open /dev/ptmx - %s ]\n",strerror(errno));
	return -1;
	}
	fcntl(ptm, F_SETFD, FD_CLOEXEC);

	if(grantpt(ptm) \|\| unlockpt(ptm) \|\|
	((devname = (char*) ptsname(ptm)) == 0)){
	LOGE("[ trouble with /dev/ptmx - %s ]\n", strerror(errno));
	return -1;
	}

	pid = fork();
	if(pid < 0) {
	LOGE("- fork failed: %s -\n", strerror(errno));
	return -1;
	}

	if(pid == 0){
	close(ptm);

	int pts;

	setsid();

	pts = open(devname, O_RDWR);
	if(pts < 0) exit(-1);

	dup2(pts, 0);
	dup2(pts, 1);
	dup2(pts, 2);

	execl(cmd, cmd, arg0, arg1, NULL);
	exit(-1);
	} else {
	*pProcessId = (int) pid;
	return ptm;
	}
	}


	static jobject android_os_Exec_createSubProcess(JNIEnv *env, jobject clazz,
	jstring cmd, jstring arg0, jstring arg1, jintArray processIdArray)
	{
	const jchar* str = cmd ? env->GetStringCritical(cmd, 0) : 0;
	String8 cmd_8;
	if (str) {
	cmd_8.set(str, env->GetStringLength(cmd));
	env->ReleaseStringCritical(cmd, str);
	}

	str = arg0 ? env->GetStringCritical(arg0, 0) : 0;
	const char* arg0Str = 0;
	String8 arg0_8;
	if (str) {
	arg0_8.set(str, env->GetStringLength(arg0));
	env->ReleaseStringCritical(arg0, str);
	arg0Str = arg0_8.string();
	}

	str = arg1 ? env->GetStringCritical(arg1, 0) : 0;
	const char* arg1Str = 0;
	String8 arg1_8;
	if (str) {
	arg1_8.set(str, env->GetStringLength(arg1));
	env->ReleaseStringCritical(arg1, str);
	arg1Str = arg1_8.string();
	}

	int procId;
	int ptm = create_subprocess(cmd_8.string(), arg0Str, arg1Str, &procId);

	if (processIdArray) {
	int procIdLen = env->GetArrayLength(processIdArray);
	if (procIdLen > 0) {
	jboolean isCopy;

	int* pProcId = (int*) env->GetPrimitiveArrayCritical(processIdArray, &isCopy);
	if (pProcId) {
	*pProcId = procId;
	env->ReleasePrimitiveArrayCritical(processIdArray, pProcId, 0);
	}
	}
	}

	jobject result = env->NewObject(class_fileDescriptor, method_fileDescriptor_init);

	if (!result) {
	LOGE("Couldn't create a FileDescriptor.");
	}
	else {
	env->SetIntField(result, field_fileDescriptor_descriptor, ptm);
	}

	return result;
	}


	static void android_os_Exec_setPtyWindowSize(JNIEnv *env, jobject clazz,
	jobject fileDescriptor, jint row, jint col, jint xpixel, jint ypixel)
	{
	int fd;
	struct winsize sz;

	fd = env->GetIntField(fileDescriptor, field_fileDescriptor_descriptor);

	if (env->ExceptionOccurred() != NULL) {
	return;
	}

	sz.ws_row = row;
	sz.ws_col = col;
	sz.ws_xpixel = xpixel;
	sz.ws_ypixel = ypixel;

	ioctl(fd, TIOCSWINSZ, &sz);
	}

	static int android_os_Exec_waitFor(JNIEnv *env, jobject clazz,
	jint procId) {
	int status;
	waitpid(procId, &status, 0);
	int result = 0;
	if (WIFEXITED(status)) {
	result = WEXITSTATUS(status);
	}
	return result;
	}

	static void android_os_Exec_close(JNIEnv *env, jobject clazz, jobject fileDescriptor)
	{
	int fd;
	struct winsize sz;

	fd = env->GetIntField(fileDescriptor, field_fileDescriptor_descriptor);

	if (env->ExceptionOccurred() != NULL) {
	return;
	}

	close(fd);
	}


	static int register_FileDescriptor(JNIEnv *env)
	{
	class_fileDescriptor = env->FindClass("java/io/FileDescriptor");

	if (class_fileDescriptor == NULL) {
	LOGE("Can't find java/io/FileDescriptor");
	return -1;
	}

	field_fileDescriptor_descriptor = env->GetFieldID(class_fileDescriptor, "descriptor", "I");

	if (field_fileDescriptor_descriptor == NULL) {
	LOGE("Can't find FileDescriptor.descriptor");
	return -1;
	}

	method_fileDescriptor_init = env->GetMethodID(class_fileDescriptor, "<init>", "()V");
	if (method_fileDescriptor_init == NULL) {
	LOGE("Can't find FileDescriptor.init");
	return -1;
	}
	return 0;
	}


	static const char *classPathName = "com/android/term/Exec";

	static JNINativeMethod method_table[] = {
	{ "createSubprocess", "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;[I)Ljava/io/FileDescriptor;",
	(void*) android_os_Exec_createSubProcess },
	{ "setPtyWindowSize", "(Ljava/io/FileDescriptor;IIII)V",
	(void*) android_os_Exec_setPtyWindowSize},
	{ "waitFor", "(I)I",
	(void*) android_os_Exec_waitFor},
	{ "close", "(Ljava/io/FileDescriptor;)V",
	(void*) android_os_Exec_close}
	};

	/*
	* Register several native methods for one class.
	*/
	static int registerNativeMethods(JNIEnv* env, const char* className,
	JNINativeMethod* gMethods, int numMethods)
	{
	jclass clazz;

	clazz = env->FindClass(className);
	if (clazz == NULL) {
	LOGE("Native registration unable to find class '%s'", className);
	return JNI_FALSE;
	}
	if (env->RegisterNatives(clazz, gMethods, numMethods) < 0) {
	LOGE("RegisterNatives failed for '%s'", className);
	return JNI_FALSE;
	}

	return JNI_TRUE;
	}

	/*
	* Register native methods for all classes we know about.
	*
	* returns JNI_TRUE on success.
	*/
	static int registerNatives(JNIEnv* env)
	{
	if (!registerNativeMethods(env, classPathName, method_table,
	sizeof(method_table) / sizeof(method_table[0]))) {
	return JNI_FALSE;
	}

	return JNI_TRUE;
	}


	// ----------------------------------------------------------------------------

	/*
	* This is called by the VM when the shared library is first loaded.
	*/

	typedef union {
	JNIEnv* env;
	void* venv;
	} UnionJNIEnvToVoid;

	jint JNI_OnLoad(JavaVM* vm, void* reserved) {
	UnionJNIEnvToVoid uenv;
	uenv.venv = NULL;
	jint result = -1;
	JNIEnv* env = NULL;

	LOGI("JNI_OnLoad");

	if (vm->GetEnv(&uenv.venv, JNI_VERSION_1_4) != JNI_OK) {
	LOGE("ERROR: GetEnv failed");
	goto bail;
	}
	env = uenv.env;

	if ((result = register_FileDescriptor(env)) < 0) {
	LOGE("ERROR: registerFileDescriptor failed");
	goto bail;
	}

	if (registerNatives(env) != JNI_TRUE) {
	LOGE("ERROR: registerNatives failed");
	goto bail;
	}

	result = JNI_VERSION_1_4;

	bail:
	return result;
	}