AS SerialPort 编译依赖库

 

一.

1.1.新建工程 选择Native C++  

 1.1.

a.SerialPort.c

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/*  * Copyright 2009-2011 Cedric Priscal  *  * 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.  */   #include <termios.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <string.h> #include <jni.h>   #include "SerialPort.h"   #include "android/log.h" static const char *TAG="serial_port"; #define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO,  TAG, fmt, ##args) #define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args) #define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args) int fd; int xh_baudrate;   #define TIOCSRS485      0x542F   struct xh_serial_rs485 {     unsigned long   flags;          /* RS485 feature flags */     unsigned long   delay_rts_before_send;  /* Delay before send (milliseconds) */     unsigned long   delay_rts_after_send;   /* Delay after send (milliseconds) */ };   static speed_t getBaudrate(jint baudrate) {     switch(baudrate) {         case 0: return B0;         case 50: return B50;         case 75: return B75;         case 110: return B110;         case 134: return B134;         case 150: return B150;         case 200: return B200;         case 300: return B300;         case 600: return B600;         case 1200: return B1200;         case 1800: return B1800;         case 2400: return B2400;         case 4800: return B4800;         case 9600: return B9600;         case 19200: return B19200;         case 38400: return B38400;         case 57600: return B57600;         case 115200: return B115200;         case 230400: return B230400;         case 460800: return B460800;         case 500000: return B500000;         case 576000: return B576000;         case 921600: return B921600;         case 1000000: return B1000000;         case 1152000: return B1152000;         case 1500000: return B1500000;         case 2000000: return B2000000;         case 2500000: return B2500000;         case 3000000: return B3000000;         case 3500000: return B3500000;         case 4000000: return B4000000;         default: return -1;     } }   /** * 设置串口数据，校验位,速率，停止位 * @param nBits 类型 int数据位 取值 位7或8 * @param nEvent 类型 char 校验类型 取值N ,E, O,,S * @param mStop 类型 int 停止位 取值1 或者 2 */   int set_opt(jint nBits, jchar nEvent, jint nStop,jint baudrate) {     LOGE("set_opt:nBits=%d,nEvent=%c,nStop=%d", nBits, nEvent, nStop);     struct termios newtio;     speed_t speed;     if(tcgetattr(fd, & newtio) != 0)     {         LOGE("setup serial failure");         return -1;     }       /*波特率 */     {         speed = getBaudrate(baudrate);         if (speed == -1)         {             /* TODO: throw an exception */             LOGE("Invalid baudrate");             return NULL;         }     }       bzero( & newtio, sizeof(newtio));     //c_cflag标志可以定义CLOCAL和CREAD，这将确保该程序不被其他端口控制和信号干扰，同时串口驱动将读取进入的数据。CLOCAL和CREAD通常总是被是能的     newtio.c_cflag |= CLOCAL | CREAD;         cfmakeraw(&newtio);     //设置波特率     cfsetispeed(&newtio, speed);     cfsetospeed(&newtio, speed);       switch(nBits) //设置数据位数     {         case 7:             newtio.c_cflag &= ~CSIZE;             newtio.c_cflag |= CS7;             break;         case 8:             newtio.c_cflag &= ~CSIZE;             newtio.c_cflag |= CS8;             break;         default:             break;     }       switch(nEvent) //设置校验位     {         case 'O':             newtio.c_cflag |= PARENB; //enable parity checking             newtio.c_cflag |= PARODD; //奇校验位             newtio.c_iflag |= (INPCK );             break;         case 'E':             newtio.c_cflag |= PARENB; //             newtio.c_cflag &= ~PARODD; //偶校验位             newtio.c_iflag |= (INPCK);             break;         case 'N':             newtio.c_cflag &= ~PARENB; //清除校验位             break;         default:             break;     }     newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); /*Input*/       newtio.c_oflag &= ~OPOST; /*Output*/       switch(nStop) //设置停止位     {         case 1:             newtio.c_cflag &= ~CSTOPB;             break;         case 2:             newtio.c_cflag |= CSTOPB;             break;         default:             // LOGW("nStop:%d,invalid param", nStop);             break;     }     newtio.c_cc[VTIME] = 100;//设置等待时间     newtio.c_cc[VMIN] = 0;//设置最小接收字符     tcflush(fd, TCIFLUSH);     if(tcsetattr(fd, TCSANOW, & newtio) != 0)     {         LOGE("options set error");         return -1;     }       LOGE("options set success");     return 1; }   /*  * Class:     android_serialport_SerialPort  * Method:    open  * Signature: (Ljava/lang/String;II)Ljava/io/FileDescriptor;  */ JNIEXPORT jobject JNICALL Java_android_1serialport_1api_SerialPort_open         (JNIEnv *env, jclass thiz, jstring path, jint baudrate,          jint databits, jint stopbits, jchar parity) {     LOGE("Java_android_1serialport_1api_SerialPort_open\n");       jobject mFileDescriptor;       speed_t speed;       xh_baudrate=baudrate;       /* Check arguments */     {         speed = getBaudrate(baudrate);         if (speed == -1) {             /* TODO: throw an exception */             LOGE("Invalid baudrate");             return NULL;         }     }       /* Opening device */     {         jint flags = 0;         jboolean iscopy;         const char *path_utf = (*env)->GetStringUTFChars(env, path, &iscopy);         LOGD("Opening serial port %s with flags 0x%x", path_utf, O_RDWR | flags);         fd = open(path_utf, O_RDWR | O_NONBLOCK);         //fd=fd;         LOGD("open() fd = %d", fd);         (*env)->ReleaseStringUTFChars(env, path, path_utf);         if (fd == -1)         {             /* Throw an exception */             LOGE("Cannot open port");             /* TODO: throw an exception */             return NULL;         }     }     /* Configure device */     {         struct termios cfg;         LOGD("Configuring serial port");         if (tcgetattr(fd, &cfg))         {             LOGE("tcgetattr() failed");             close(fd);             /* TODO: throw an exception */             return NULL;         }           cfmakeraw(&cfg);         cfsetispeed(&cfg, speed);         cfsetospeed(&cfg, speed);           if (tcsetattr(fd, TCSANOW, &cfg))         {             LOGE("tcsetattr() failed");             close(fd);             /* TODO: throw an exception */             return NULL;         }     }     //配置校验位 停止位等等     //set_opt(databits, parity, stopbits,baudrate);         /* Create a corresponding file descriptor */     {         jclass cFileDescriptor = (*env)->FindClass(env, "java/io/FileDescriptor");         jmethodID iFileDescriptor = (*env)->GetMethodID(env, cFileDescriptor, "<init>", "()V");         jfieldID descriptorID = (*env)->GetFieldID(env, cFileDescriptor, "descriptor", "I");         mFileDescriptor = (*env)->NewObject(env, cFileDescriptor, iFileDescriptor);         (*env)->SetIntField(env, mFileDescriptor, descriptorID, (jint)fd);     }       return mFileDescriptor; }   /*  * Class:     cedric_serial_SerialPort  * Method:    close  * Signature: ()V  */ JNIEXPORT void JNICALL Java_android_1serialport_1api_SerialPort_close (JNIEnv *env, jobject thiz) { jclass SerialPortClass = (*env)->GetObjectClass(env, thiz); jclass FileDescriptorClass = (*env)->FindClass(env, "java/io/FileDescriptor");   jfieldID mFdID = (*env)->GetFieldID(env, SerialPortClass, "mFd", "Ljava/io/FileDescriptor;"); jfieldID descriptorID = (*env)->GetFieldID(env, FileDescriptorClass, "descriptor", "I");   jobject mFd = (*env)->GetObjectField(env, thiz, mFdID); jint descriptor = (*env)->GetIntField(env, mFd, descriptorID);   LOGD("close(fd = %d)", descriptor); close(descriptor); } /*  * Class:     cedric_serial_SerialPort  * Method:    close  * Signature: ()V  */ JNIEXPORT void JNICALL Java_android_1serialport_1api_SerialPort_write_1rs485_1length (JNIEnv *env, jobject thiz, jint count) { struct xh_serial_rs485 rs485conf;   LOGD("count=  %d xh_baudrate = %d \n", count,xh_baudrate);   rs485conf.delay_rts_after_send = ((10 * count * 1000 ) / xh_baudrate) + 1  ;   ioctl (fd, TIOCSRS485, &rs485conf);   }

b.SerialPort.h 

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/* DO NOT EDIT THIS FILE - it is machine generated */ #include <jni.h> /* Header for class android_serialport_api_SerialPort */   #ifndef _Included_android_serialport_api_SerialPort #define _Included_android_serialport_api_SerialPort #ifdef __cplusplus extern "C" { #endif /*  * Class:     android_serialport_api_SerialPort  * Method:    open  * Signature: (Ljava/lang/String;II)Ljava/io/FileDescriptor;  */ JNIEXPORT jobject JNICALL Java_android_1serialport_1api_SerialPort_open         (JNIEnv *, jclass, jstring, jint, jint,jint,jchar);   /*  * Class:     android_serialport_api_SerialPort  * Method:    close  * Signature: ()V  */ JNIEXPORT void JNICALL Java_android_1serialport_1api_SerialPort_close (JNIEnv *, jobject);   JNIEXPORT void JNICALL Java_android_1serialport_1api_SerialPort_write_rs485_length (JNIEnv *, jint);     #ifdef __cplusplus } #endif #endif

c.CMakeLists.txt

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# For more information about using CMake with Android Studio, read the # documentation: https://d.android.com/studio/projects/add-native-code.html   # Sets the minimum version of CMake required to build the native library.   cmake_minimum_required(VERSION 3.10.2)   # Declares and names the project.   project("serialport")   # Creates and names a library, sets it as either STATIC # or SHARED, and provides the relative paths to its source code. # You can define multiple libraries, and CMake builds them for you. # Gradle automatically packages shared libraries with your APK.   add_library( # Sets the name of the library.         SerialPort           # Sets the library as a shared library.         SHARED           # Provides a relative path to your source file(s).         SerialPort.c)   # Searches for a specified prebuilt library and stores the path as a # variable. Because CMake includes system libraries in the search path by # default, you only need to specify the name of the public NDK library # you want to add. CMake verifies that the library exists before # completing its build.   find_library( # Sets the name of the path variable.         log-lib           # Specifies the name of the NDK library that         # you want CMake to locate.         log)   # Specifies libraries CMake should link to your target library. You # can link multiple libraries, such as libraries you define in this # build script, prebuilt third-party libraries, or system libraries.   target_link_libraries( # Specifies the target library.         SerialPort           # Links the target library to the log library         # included in the NDK.         ${log-lib})

E:\GatsbyDevelop\AndroidStuido\GatsbyASCode\GSerialPort\app\build\intermediates\cmake\debug\obj\arm64-v8a   下生成so文件

工程

1.3.

android_serialport_api

a.SerialPort.java  这个类主要用来加载SO文件 通过JNI的方式打开关闭串口

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package android_serialport_api;   import android.util.Log;   import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream;   public class SerialPort {       private static final String TAG = "SerialPort";       /*      * Do not remove or rename the field mFd: it is used by native method close();      */     private FileDescriptor mFd;     private FileInputStream mFileInputStream;     private FileOutputStream mFileOutputStream;       public SerialPort(File device, int baudrate, int dataBits, int stopBits, char parity) throws SecurityException, IOException {           /* Check access permission */         if (!device.canRead() || !device.canWrite()) {             try {                 /* Missing read/write permission, trying to chmod the file */                 Process su;                 su = Runtime.getRuntime().exec("/system/bin/su");                 String cmd = "chmod 666 " + device.getAbsolutePath() + "\n"                         + "exit\n";                 su.getOutputStream().write(cmd.getBytes());                 if ((su.waitFor() != 0) || !device.canRead()                         || !device.canWrite()) {                     throw new SecurityException();                 }             } catch (Exception e) {                 e.printStackTrace();                 throw new SecurityException();             }         }           mFd = open(device.getAbsolutePath(), baudrate, dataBits, stopBits, parity);         if (mFd == null) {             Log.e(TAG, "native open returns null");             throw new IOException();         }         mFileInputStream = new FileInputStream(mFd);         mFileOutputStream = new FileOutputStream(mFd);     }       // Getters and setters     public InputStream getInputStream() {         return mFileInputStream;     }       public OutputStream getOutputStream() {         return mFileOutputStream;     }       public void Write_Rs485_Length(int count) {         write_rs485_length(count);     }       // JNI(调用java本地接口，实现串口的打开和关闭)     /**串口有五个重要的参数：串口设备名，波特率，检验位，数据位，停止位     其中检验位一般默认位NONE,数据位一般默认为8，停止位默认为1*/     /**      * @param path     串口设备的据对路径      * @param baudrate 波特率      * @param dataBits 数据位      * @param stopBits 停止位      * @param parity   校验位      */     private native static FileDescriptor open(String path, int baudrate, int dataBits, int stopBits, char parity);       public native void close();       public native void write_rs485_length(int count);       static {//加载jni下的C文件库         System.loadLibrary("serial_port");     } }

b.SerialPortFinder.java

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/*  * Copyright 2009-2011 Cedric Priscal  *  * 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.  */   #include <termios.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <string.h> #include <jni.h>   #include "SerialPort.h"   #include "android/log.h" static const char *TAG="serial_port"; #define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO,  TAG, fmt, ##args) #define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args) #define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args) int fd; int xh_baudrate;   #define TIOCSRS485      0x542F   struct xh_serial_rs485 {     unsigned long   flags;          /* RS485 feature flags */     unsigned long   delay_rts_before_send;  /* Delay before send (milliseconds) */     unsigned long   delay_rts_after_send;   /* Delay after send (milliseconds) */ };   static speed_t getBaudrate(jint baudrate) {     switch(baudrate) {         case 0: return B0;         case 50: return B50;         case 75: return B75;         case 110: return B110;         case 134: return B134;         case 150: return B150;         case 200: return B200;         case 300: return B300;         case 600: return B600;         case 1200: return B1200;         case 1800: return B1800;         case 2400: return B2400;         case 4800: return B4800;         case 9600: return B9600;         case 19200: return B19200;         case 38400: return B38400;         case 57600: return B57600;         case 115200: return B115200;         case 230400: return B230400;         case 460800: return B460800;         case 500000: return B500000;         case 576000: return B576000;         case 921600: return B921600;         case 1000000: return B1000000;         case 1152000: return B1152000;         case 1500000: return B1500000;         case 2000000: return B2000000;         case 2500000: return B2500000;         case 3000000: return B3000000;         case 3500000: return B3500000;         case 4000000: return B4000000;         default: return -1;     } }   /** * 设置串口数据，校验位,速率，停止位 * @param nBits 类型 int数据位 取值 位7或8 * @param nEvent 类型 char 校验类型 取值N ,E, O,,S * @param mStop 类型 int 停止位 取值1 或者 2 */   int set_opt(jint nBits, jchar nEvent, jint nStop,jint baudrate) {     LOGE("set_opt:nBits=%d,nEvent=%c,nStop=%d", nBits, nEvent, nStop);     struct termios newtio;     speed_t speed;     if(tcgetattr(fd, & newtio) != 0)     {         LOGE("setup serial failure");         return -1;     }       /*波特率 */     {         speed = getBaudrate(baudrate);         if (speed == -1)         {             /* TODO: throw an exception */             LOGE("Invalid baudrate");             return NULL;         }     }       bzero( & newtio, sizeof(newtio));     //c_cflag标志可以定义CLOCAL和CREAD，这将确保该程序不被其他端口控制和信号干扰，同时串口驱动将读取进入的数据。CLOCAL和CREAD通常总是被是能的     newtio.c_cflag |= CLOCAL | CREAD;         cfmakeraw(&newtio);     //设置波特率     cfsetispeed(&newtio, speed);     cfsetospeed(&newtio, speed);       switch(nBits) //设置数据位数     {         case 7:             newtio.c_cflag &= ~CSIZE;             newtio.c_cflag |= CS7;             break;         case 8:             newtio.c_cflag &= ~CSIZE;             newtio.c_cflag |= CS8;             break;         default:             break;     }       switch(nEvent) //设置校验位     {         case 'O':             newtio.c_cflag |= PARENB; //enable parity checking             newtio.c_cflag |= PARODD; //奇校验位             newtio.c_iflag |= (INPCK );             break;         case 'E':             newtio.c_cflag |= PARENB; //             newtio.c_cflag &= ~PARODD; //偶校验位             newtio.c_iflag |= (INPCK);             break;         case 'N':             newtio.c_cflag &= ~PARENB; //清除校验位             break;         default:             break;     }     newtio.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); /*Input*/       newtio.c_oflag &= ~OPOST; /*Output*/       switch(nStop) //设置停止位     {         case 1:             newtio.c_cflag &= ~CSTOPB;             break;         case 2:             newtio.c_cflag |= CSTOPB;             break;         default:             // LOGW("nStop:%d,invalid param", nStop);             break;     }     newtio.c_cc[VTIME] = 100;//设置等待时间     newtio.c_cc[VMIN] = 0;//设置最小接收字符     tcflush(fd, TCIFLUSH);     if(tcsetattr(fd, TCSANOW, & newtio) != 0)     {         LOGE("options set error");         return -1;     }       LOGE("options set success");     return 1; }   /*  * Class:     android_serialport_SerialPort  * Method:    open  * Signature: (Ljava/lang/String;II)Ljava/io/FileDescriptor;  */ JNIEXPORT jobject JNICALL Java_android_1serialport_1api_SerialPort_open         (JNIEnv *env, jclass thiz, jstring path, jint baudrate,          jint databits, jint stopbits, jchar parity) {     LOGE("Java_android_1serialport_1api_SerialPort_open\n");       jobject mFileDescriptor;       speed_t speed;       xh_baudrate=baudrate;       /* Check arguments */     {         speed = getBaudrate(baudrate);         if (speed == -1) {             /* TODO: throw an exception */             LOGE("Invalid baudrate");             return NULL;         }     }       /* Opening device */     {         jint flags = 0;         jboolean iscopy;         const char *path_utf = (*env)->GetStringUTFChars(env, path, &iscopy);         LOGD("Opening serial port %s with flags 0x%x", path_utf, O_RDWR | flags);         fd = open(path_utf, O_RDWR | O_NONBLOCK);         //fd=fd;         LOGD("open() fd = %d", fd);         (*env)->ReleaseStringUTFChars(env, path, path_utf);         if (fd == -1)         {             /* Throw an exception */             LOGE("Cannot open port");             /* TODO: throw an exception */             return NULL;         }     }     /* Configure device */     {         struct termios cfg;         LOGD("Configuring serial port");         if (tcgetattr(fd, &cfg))         {             LOGE("tcgetattr() failed");             close(fd);             /* TODO: throw an exception */             return NULL;         }           cfmakeraw(&cfg);         cfsetispeed(&cfg, speed);         cfsetospeed(&cfg, speed);           if (tcsetattr(fd, TCSANOW, &cfg))         {             LOGE("tcsetattr() failed");             close(fd);             /* TODO: throw an exception */             return NULL;         }     }     //配置校验位 停止位等等     //set_opt(databits, parity, stopbits,baudrate);         /* Create a corresponding file descriptor */     {         jclass cFileDescriptor = (*env)->FindClass(env, "java/io/FileDescriptor");         jmethodID iFileDescriptor = (*env)->GetMethodID(env, cFileDescriptor, "<init>", "()V");         jfieldID descriptorID = (*env)->GetFieldID(env, cFileDescriptor, "descriptor", "I");         mFileDescriptor = (*env)->NewObject(env, cFileDescriptor, iFileDescriptor);         (*env)->SetIntField(env, mFileDescriptor, descriptorID, (jint)fd);     }       return mFileDescriptor; }   /*  * Class:     cedric_serial_SerialPort  * Method:    close  * Signature: ()V  */ JNIEXPORT void JNICALL Java_android_1serialport_1api_SerialPort_close (JNIEnv *env, jobject thiz) { jclass SerialPortClass = (*env)->GetObjectClass(env, thiz); jclass FileDescriptorClass = (*env)->FindClass(env, "java/io/FileDescriptor");   jfieldID mFdID = (*env)->GetFieldID(env, SerialPortClass, "mFd", "Ljava/io/FileDescriptor;"); jfieldID descriptorID = (*env)->GetFieldID(env, FileDescriptorClass, "descriptor", "I");   jobject mFd = (*env)->GetObjectField(env, thiz, mFdID); jint descriptor = (*env)->GetIntField(env, mFd, descriptorID);   LOGD("close(fd = %d)", descriptor); close(descriptor); } /*  * Class:     cedric_serial_SerialPort  * Method:    close  * Signature: ()V  */ JNIEXPORT void JNICALL Java_android_1serialport_1api_SerialPort_write_1rs485_1length (JNIEnv *env, jobject thiz, jint count) { struct xh_serial_rs485 rs485conf;   LOGD("count=  %d xh_baudrate = %d \n", count,xh_baudrate);   rs485conf.delay_rts_after_send = ((10 * count * 1000 ) / xh_baudrate) + 1  ;   ioctl (fd, TIOCSRS485, &rs485conf);   }