NDK开发（二），ndk开发前景

2023-11-02 23:13:04

#define LOGE(FORMAT, …) __android_log_print(ANDROID_LOG_ERROR,“huangxiaoguo”,FORMAT,VA_ARGS)

char password[] = “huangxiaoguo”;

//加密

JNIEXPORT void JNICALL Java_cn_tsou_ndkfilecrypt_ndk_Cryptor_crypt

(JNIEnv *env, jclass jcls, jstring normal_path_jstr, jstring crypt_path_jstr) {

//jstring ->char*

const char *normal_path = (*env)->GetStringUTFChars(env, normal_path_jstr, NULL);

const char *crypt_path = (*env)->GetStringUTFChars(env, crypt_path_jstr, NULL);

LOGI(" path1:%s", normal_path);

LOGI(" path2:%s", crypt_path);

//打开文件

FILE *normal_fp = fopen(normal_path, “rb”);

FILE *crypt_fp = fopen(crypt_path, “wb”);

//一次读取一个字符

int ch;

int i = 0;//循环使用密码中的字母进行疑惑运算

int pwd_len = strlen(password);//密码的长度

while ((ch = fgetc(normal_fp)) != EOF) { //End of File

//写入（异或运算）

fputc(ch ^ password[i % pwd_len], crypt_fp);

i++;

}

//关闭

fclose(crypt_fp);

fclose(normal_fp);

(*env)->ReleaseStringUTFChars(env, normal_path_jstr, normal_path);

(*env)->ReleaseStringUTFChars(env, crypt_path_jstr, crypt_path);

}

//解密

JNIEXPORT void JNICALL Java_cn_tsou_ndkfilecrypt_ndk_Cryptor_decrypt

(JNIEnv *env, jclass jcls, jstring crypt_path_jstr, jstring decrypt_path_jstr) {

//jstring ->char*

const char *crypt_path = (*env)->GetStringUTFChars(env, crypt_path_jstr, NULL);

const char *decrypt_path = (*env)->GetStringUTFChars(env, decrypt_path_jstr, NULL);

//打开文件

FILE *crypt_fp = fopen(crypt_path, “rb”);

FILE *decrypt_fp = fopen(decrypt_path, “wb”);

//一次读取一个字符

int ch;

int i = 0;//循环使用密码中的字母进行异或运算

int pwd_len = strlen(password);//密码的长度

while ((ch = fgetc(crypt_fp)) != EOF) { //End of File

//写入（异或运算）

fputc(ch ^ password[i % pwd_len], decrypt_fp);

i++;

}

//关闭

fclose(decrypt_fp);

fclose(crypt_fp);

(*env)->ReleaseStringUTFChars(env, crypt_path_jstr, crypt_path);

(*env)->ReleaseStringUTFChars(env, decrypt_path_jstr, decrypt_path);

}

//获取文件大小

int get_file_size(char *path) {

FILE *fp = fopen(path, “rb”);

fseek(fp, 0, SEEK_END);

return ftell(fp);

}

//拆分

JNIEXPORT void JNICALL Java_cn_tsou_ndkfilecrypt_ndk_Cryptor_diff

(JNIEnv *env, jclass jcls, jstring path_jstr, jstring path_pattern_jstr, jint file_num) {

//jstring ->char*

//需要分割的文件路径

const char *path = (*env)->GetStringUTFChars(env, path_jstr, NULL);

const char *path_pattern = (*env)->GetStringUTFChars(env, path_pattern_jstr, NULL);

//得到分割之后的子文件路径列表

char **pathches = malloc(sizeof(char *) * file_num);

int i = 0;

//不断读取path文件，循环写入file_num个文件中

for (; i < file_num; ++i) {

pathches[i] = malloc(sizeof(char) * 100);

//元素赋值

//需要分割的文件：C://jason/001.jpg

// 子文件:C://jason/001_%d.jpg

sprintf(pathches[i], path_pattern, (i + 1));

LOGI(“patch path:%s”, pathches[i]);

}

/**

  • 整除：

  • 文件大小：90，分成9个文件，每个文件10

  • 不整除：

  • 文件大小：110，分成9个文件，

  • 前（9-1）个文件为（110/(9-1)）=13

  • 最后一个文件（110%(9-1)）=6

  • (这个逻辑有问题104出现最后一个文件为0的问题,可自行判断)

*/

int filesize = get_file_size(path);

FILE *fpr = fopen(path, “rb”);

//整除

if (filesize % file_num == 0) {

//单个文件大小

int part = filesize / file_num;

i = 0;

//逐一写入不同的分割子文件中

for (; i < file_num; ++i) {

FILE *fpw = fopen(pathches[i], “wb”);

int j = 0;

for (; j < part; ++j) {

//边读编写

fputc(fgetc(fpr), fpw);

}

fclose(fpw);

}

} else {

//不能整除

int part = filesize / (file_num - 1);

i = 0;

//逐一写入不同的分割子文件中

for (; i < file_num - 1; ++i) {

FILE *fpw = fopen(pathches[i], “wb”);

int j = 0;

for (; j < part; ++j) {

//边读编写

fputc(fgetc(fpr), fpw);

}

fclose(fpw);

}

//最后一个

FILE *fpw = fopen(pathches[file_num - 1], “wb”);

i = 0;

for (; i < filesize % (file_num - 1); ++i) {

//边读编写

fputc(fgetc(fpr), fpw);

}

fclose(fpw);

}

fclose(fpr);

//释放

i = 0;

for (; i < file_num; ++i) {

free(pathches[i]);

}

free(pathches);

(*env)->ReleaseStringUTFChars(env, path_jstr, path);

(*env)->ReleaseStringUTFChars(env, path_pattern_jstr, path_pattern);

}

//合并

JNIEXPORT void JNICALL Java_cn_tsou_ndkfilecrypt_ndk_Cryptor_path

(JNIEnv *env, jclass jcls, jstring path_pattern_jstr, jint file_num, jstring total_jstr) {

//合并之后的文件

const char *merge_path = (*env)->GetStringUTFChars(env, total_jstr, NULL);

//分割指纹机的pattern

const char *path_pattern = (*env)->GetStringUTFChars(env, path_pattern_jstr, NULL);

//得到分割之后的子文件路径列表

char **pathches = malloc(sizeof(char *) * file_num);

int i = 0;

//不断读取path文件，循环写入file_num个文件中

for (; i < file_num; ++i) {

pathches[i] = malloc(sizeof(char) * 100);

//元素赋值

//需要分割的文件：C://jason/001.jpg

// 子文件:C://jason/001_%d.jpg

sprintf(pathches[i], path_pattern, (i + 1));

LOGI(“patch path:%s”, pathches[i]);

}

FILE *fpw = fopen(merge_path,“wb”);

//把所有的分割文件读取一遍，写入总的文件中

i=0;

for (; i < file_num; ++i) {

//每个子文件的大小

int filesize=get_file_size(pathches[i]);

FILE *fpr=fopen(pathches[i],“rb”);

int j=0;

for (; j <filesize ; ++j) {

fputc(fgetc(fpr),fpw);

}

fclose(fpr);

}

fclose(fpw);

//释放

i = 0;

for (; i < file_num; ++i) {

free(pathches[i]);

}

free(pathches);

(*env)->ReleaseStringUTFChars(env, total_jstr, merge_path);

(*env)->ReleaseStringUTFChars(env, path_pattern_jstr, path_pattern);

}

  • 调用

iNDK开发（二），ndk开发前景
mport android.Manifest;

import android.content.pm.PackageManager;

import android.os.Bundle;

import android.os.Environment;

import android.support.annotation.NonNull;

import android.support.v4.app.ActivityCompat;

import android.support.v7.app.AppCompatActivity;

import android.util.Log;

import android.view.View;

import java.io.File;

import cn.tsou.ndkfilecrypt.ndk.Cryptor;

public class MainActivity extends AppCompatActivity {

String[] mPermissionList = new String[]{

Manifest.permission.WRITE_EXTERNAL_STORAGE,

Manifest.permission.READ_EXTERNAL_STORAGE};

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

}

@Override

public void onAttachedToWindow() {

super.onAttachedToWindow();

ActivityCompat.requestPermissions(MainActivity.this, mPermissionList, 100);

}

@Override

public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {

switch (requestCode) {

case 100:

boolean writeExternalStorage = grantResults[0] == PackageManager.PERMISSION_GRANTED;

boolean readExternalStorage = grantResults[1] == PackageManager.PERMISSION_GRANTED;

if (grantResults.length > 0 && writeExternalStorage && readExternalStorage) {

}

break;

}

}

/**

  • 加密

  • @param view

*/

public void mCrypt(View view) {

String normal_path = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separatorChar +

“huangxiaoguo” + File.separatorChar + “001.png”;

String crypt_path = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separatorChar +

lts[1] == PackageManager.PERMISSION_GRANTED;

if (grantResults.length > 0 && writeExternalStorage && readExternalStorage) {

}

break;

}

}

/**

  • 加密

  • @param view

*/

public void mCrypt(View view) {

String normal_path = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separatorChar +

“huangxiaoguo” + File.separatorChar + “001.png”;

String crypt_path = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separatorChar +

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