weeklog 10

12.24~12.28

  周一。昨晚发现被窝里看手机，背光还是太亮，试着加一个level，当环境光线低于40，背光设为10。根据配置里的比例改kernel。其依据是配置里的config_autoBrightnessLevels发的身份，并将最亮背光的最低环境光要求设为40w，这是估算，今天线忘带，明天实际测下，看阳光下能到多少背光，再调整。

配置有点怪异，第三级背光突然增加，外界环境光增速是2.5 4 2.5 3，对应背光增速是2.5 4 1.5 1.33 1.25

  //6 levels, depending on the config_autoBrightnessLcdBacklightValues in config.xml
    //and get 400000 as the minimum requirement of the max level
    if(lux >= 5334 && lux < 13333)
            lux = 8000;//1
        else if(lux >= 13333 && lux < 53333)
            lux = 16000;//2
        else if(lux >= 53333 && lux < 133333)
            lux = 30000;//3
        else if(lux >= 133333 && lux < 399999)
            lux = 100000;//12
            //<5334 -> 0; >=399999 -> lux/8000*100-20

周二

以下代码，若在//--------------------之后加上任何一个声明，如，char a；打印出的buffer立马出错！！

原来是buffer需要初始化，把第19行改为char *buffer = malloc(1001);就好了。

因为这个指针未初始化时，给它赋值，将把值赋给不确定的内存段

#include <stdio.h>
#include <fcntl.h>
#include <locale.h>
#include <string.h>
#define FILE "shediao"

 
int main(){
    setlocale(LC_ALL, "GBK");


    #ifdef FILE
        printf("defined, FILE = %s\n", FILE);
    #endif
    printf("over\n");
    //--------------------------------------------------------------
    int f1;
    int f2;
    char *buffer;
    f1 = open(FILE, O_RDONLY);
    if (f1<0)
        printf("open_error\n");
    read(f1, buffer, 1000);
    f2 = creat("shediao_fixed", 777);
    if(f2<0)
        printf("creat_error\n");
    write(f2, buffer, 1000);
 
    
    printf("%s, length:%ld\n", buffer, strlen(buffer));
    
    close(f2);
    close(f1);


    return 0;
}

GBK编码中一个汉字占3字节，而换行符等依然是1字节

#include <stdio.h>
#include <fcntl.h>
#include <locale.h>
#include <string.h>
#include <stdlib.h>
#define FILE "shediao"
#define MYSIZE 1000
 
int main(){
    setlocale(LC_ALL, "GBK");


    #ifdef FILE
        printf("defined, FILE = %s\n", FILE);
    #endif
    printf("over\n");
    //--------------------------------------------------------------
    int f1, f2, count = MYSIZE, presentence;
    char *pr1, *pr2;
    char *buffer = malloc(MYSIZE+1);
    f1 = open(FILE, O_RDONLY);
    if (f1<0){
        printf("open_error\n");
        return -1;
    }
    f2 = creat("shediao_fixed", 777);
    if(f2<0){
        printf("creat_error\n");
        return -1;
    }

    while(count == MYSIZE){
        char *temp = malloc(MYSIZE+1);
        count = read(f1, buffer, MYSIZE);
        if(count<0){
            printf("read error\n");
            return -1;
        }
        pr1 = buffer;
        pr2 = pr1;
        while(pr1 < buffer + MYSIZE){
            if(*pr1 == '\n'){
                if(pr1 - pr2 >= 26*3){
                    strncat(temp, pr2, pr1-pr2);
                    //printf("\n26:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }else if(pr1 - pr2 >= 24*3 && presentence <= 26){
                    strncat(temp, pr2, pr1-pr2);
                    //printf("\n24:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }else{
                    strncat(temp, pr2, pr1-pr2+1);
                    //printf("\nelse:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }
                presentence = pr2 - pr1;
                pr2 = pr1+1;
            }
            pr1++;
        }
        strncat(temp, pr2, pr1-pr2);
        //printf("all:1-2 =%d temp:%s,pr1:%ld, pr2:%ld, \n", pr1 - pr2, temp, pr1, pr2);
        if(write(f2, temp, count) < 0){
            printf("write error\n");
            return -1;
        }
        //printf("length = %ld, %s\n",strlen(temp), temp);
     }    
    
    
    close(f2);
    close(f1);


    return 0;
}

调试一下午，发现原因是write(f2, temp, count);count大于temp中含字符的大小，

改为write(f2, temp, strlen(temp))。

但这仍不是全部的错误！！

41行，内层while的循环条件应该是pr1 < buffer + count，而不是MYMAX；

因为count是read后的结果，将小于等于MYMAX，它的安全性更高。使用MYMAX的结果就是在最后一次外层循环中，读取的字节数将不足1000byte，此时若仍让pr1走1000次，将会在第58行strncat(temp, pr2, pr1-pr2);刷进未知的东西，然后导致最后文件读取不了，全是乱码。

挖哈哈，哥的射雕英雄传格式终于正确，成就感油然而生，深藏功与名。

最终版本：

#include <stdio.h>
#include <fcntl.h>
#include <locale.h>
#include <string.h>
#include <stdlib.h>
#define FILE "shediao"
#define MYSIZE 1000
 
int main(){
    setlocale(LC_ALL, "GBK");


    #ifdef FILE
        printf("defined, FILE = %s\n", FILE);
    #endif
    printf("over\n");
    //--------------------------------------------------------------
    int f1, f2, count = MYSIZE, presentence;
    char *pr1, *pr2;
    char *buffer = malloc(MYSIZE+1);
    f1 = open(FILE, O_RDONLY);
    if (f1<0){
        printf("open_error\n");
        return -1;
    }
    f2 = creat("shediao_fixed", 777);
    if(f2<0){
        printf("creat_error\n");
        return -1;
    }

    while(count == MYSIZE){
        char *temp = malloc(MYSIZE+1);
        count = read(f1, buffer, MYSIZE);
        if(count<0){
            printf("read error\n");
            return -1;
        }
        pr1 = buffer;
        pr2 = pr1;
        while(pr1 < buffer + count){
            if(*pr1 == '\n'){
                if(pr1 - pr2 >= 26*3){
                    strncat(temp, pr2, pr1-pr2);
                    //printf("\n26:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }else if(pr1 - pr2 >= 24*3 && presentence <= 26){
                    strncat(temp, pr2, pr1-pr2);
                    //printf("\n24:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }else{
                    strncat(temp, pr2, pr1-pr2+1);
                    //printf("\nelse:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }
                presentence = pr2 - pr1;
                pr2 = pr1+1;
            }
            pr1++;
        }
        strncat(temp, pr2, pr1-pr2);
        //printf("all:1-2 =%d temp:%s,pr1:%ld, pr2:%ld, \n", pr1 - pr2, temp, pr1, pr2);
        if(write(f2, temp, strlen(temp)) < 0){
            printf("write error\n");
            return -1;
        }
        //printf("length = %ld, %s\n",strlen(temp), temp);
     }    
    
    
    close(f2);
    close(f1);


    return 0;
}

更新了版本，新加入变量remain_buffer，即每次read后最后一行，这行的字节数将加入下一次read第一行是否要删‘\n’的判断条件。

#include <stdio.h>
#include <fcntl.h>
#include <locale.h>
#include <string.h>
#include <stdlib.h>
#define FILE "shediao"
#define DEST_FILE "shediao_fixed"
#define MYSIZE 1000
 
int main(){
    setlocale(LC_ALL, "GBK");


    #ifdef FILE
        printf("defined, FILE = %s\n", FILE);
    #endif
    printf("over\n");
    //--------------------------------------------------------------
    int f1, f2, count = MYSIZE, presentence;
    char *pr1, *pr2;
    char *buffer = malloc(MYSIZE+1);
    signed int remain_buffer = 0;
    f1 = open(FILE, O_RDONLY);
    if (f1<0){
        printf("open_error\n");
        return -1;
    }
    f2 = creat(DEST_FILE, 777);
    if(f2<0){
        printf("creat_error\n");
        return -1;
    }

    while(count == MYSIZE){
        char *temp = malloc(MYSIZE+1);
        count = read(f1, buffer, MYSIZE);
        if(count<0){
            printf("read error\n");
            return -1;
        }
        pr1 = buffer;
        pr2 = pr1;
        while(pr1 < buffer + count){
            if(*pr1 == '\n'){
                if(pr1 - pr2 >= 26*3 || (strlen(temp)==0 && pr1 - pr2 + remain_buffer >= 26*3) ){
                    strncat(temp, pr2, pr1-pr2);
                    //printf("\n26:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }else if( (pr1 - pr2 >= 24*3 && presentence <= 26) || (strlen(temp)==0 && pr1 - pr2 + remain_buffer >= 24*3 && presentence <= 26 ) ){
                    strncat(temp, pr2, pr1-pr2);
                    //printf("\n24:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }else{
                    strncat(temp, pr2, pr1-pr2+1);
                    //printf("\nelse:%s,%ld,%ld,1-2=%d \n", temp, pr1,pr2,pr1-pr2);
                }
                presentence = pr2 - pr1;
                pr2 = pr1+1;
            }
            pr1++;
        }
        remain_buffer = pr1-pr2;
        strncat(temp, pr2, remain_buffer);
        //printf("all:1-2 =%d temp:%s,pr1:%ld, pr2:%ld, \n", pr1 - pr2, temp, pr1, pr2);
        if(write(f2, temp, strlen(temp)) < 0){
            printf("write error\n");
            return -1;
        }
        //printf("length = %ld, %s\n",strlen(temp), temp);
     }    
    
    
    close(f2);
    close(f1);


    return 0;
}

用抛异常的方法追踪调用者，提供者：Android驱动研究群，北京-Airk(qq：176951632)

Log.d(LOG_TAG, "dyyr - print caller of updateProximitySensorMode");
        try {
            throw new Exception();
        } catch (Exception e) {
            e.printStackTrace();
        }//dyyr 出现的log头是System.err

Psensor

ailt,aiht,piht,pilt
a:als a??? light sensor
p:ps proximity sensor
i:??
h,l:high, low
t:threshold

编package/app的时候会出两个目标：

Install: out/target/product/T20WG/system/app/Phone.apk

Install: out/target/product/T20WG/data/app/PhoneAppTests.apk

只用第一个就好，测试的那个没什么用