Hex文件转Bin文件

首先给大家推荐一下我老师大神的人工智能教学网站。教学不仅零基础,通俗易懂,而且非常风趣幽默,还时不时有内涵黄段子!点这里可以跳转到网站

在嵌入式开发中,编译器生成的目标文件一般都是 .hex 文件。
为什么要转换,直接使用hex文件不行吗,可是我在开发过程中一直都是直接生成hex文件,然后进行下载,也没见出错?
在不清楚hex与bin文件的格式时,可能小伙伴会有这样的疑问。需要进行转换的原因是:hex文件中数据记录(record)并不是按照 “起始地址–>终止地址” 这样的顺序进行排列的,由于每行数据都包含起始地址和数据长度,所以hex文件中数据不需要按照地址顺序从低到高进行排列;而Bin文件中的数据则是严格按照地址顺序进行排列的。

首先需要了解hex文件的格式,可以参考官方资料Intel Hexadecimal Object File Format Specification,也可以看我的另一篇blog——HEX文件说明

最近做ECU的上位机下载工具,其中一步是将hex文件的内容转成按地址顺序(从低到高)排列的二进制数据(bin文件)。
于是我找了一个转换工具——hex2bin源码地址。下面我就该工具的整个转换过程进行一些分析。
整个过程主要分为两步:
1. 遍历整个hex文件,找出最小地址和最大地址(也就是起始地址和结束地址),算出数据长度(数据长度=结束地址-起始地址),根据得到的数据长度,分配对应大小的内存(开辟一个数组);
2. 再次遍历整个hex文件,计算每条数据记录中的起始地址与hex文件起始地址的偏移量,按照偏移量将该条数据记录中的数据部分写入第一步的数组中。(这样就实现了按照从低到高的地址顺序排列整个hex文件的数据)。
最后只需要将该数组写出到文件中即可。

首先使用FILE * fopen(const char * path, const char * mode);打开hex文件,然后是第一次遍历,找出起始地址和数据长度。

    /* 第一次遍历hex文件,获取地址范围(Lowest_Address和Highest_Address) */
    /* get highest and lowest addresses so that we can allocate the right size */
    do
    {
        unsigned int i;

        /* Read a line from input file. */
        GetLine(Line,Filin);
        Record_Nb++;

        /* Remove carriage return/line feed(回车/换行) at the end of line. */
        i = strlen(Line);

        if (--i != 0)
        {
            if (Line[i] == '\n') Line[i] = '\0';

            /* Scan the first two bytes and nb of bytes.
               The two bytes are read in First_Word since its use depend on the
               record type: if it's an extended address record or a data record.
               */

            /* sscanf() - 从一个字符串中读进与指定格式匹配的数据, 成功则返回参数数目.
               ":%2x%4x%2x%s":格式说明 :冒号开头,2个十六进制数,4个十六进制数, 2个十六进制数,余下的当做字符串  */
            result = sscanf (Line, ":%2x%4x%2x%s",&Nb_Bytes,&First_Word,&Type,Data_Str);
            if (result != 4) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

            p = (char *) Data_Str; //p表示指向数据域(包括checksum)的指针

            /* If we're reading the last record, ignore it. */
            switch (Type)
            {
            /* Data record */
            case 0:
                if (Nb_Bytes == 0)
                    break;

                Address = First_Word;

                if (Seg_Lin_Select == SEGMENTED_ADDRESS)
                {
                    Phys_Addr = (Segment << 4) + Address;
                }
                else
                {
                    /* LINEAR_ADDRESS or NO_ADDRESS_TYPE_SELECTED
                       Upper_Address = 0 as specified in the Intel spec. until an extended address
                       record is read. */
                    Phys_Addr = ((Upper_Address << 16) + Address);
                }

                if (Verbose_Flag) fprintf(stderr,"Physical Address: %08X\n",Phys_Addr);

                /* 获取地址范围(Lowest_Address和Highest_Address) */
                /* Set the lowest address as base pointer. */
                if (Phys_Addr < Lowest_Address)
                    Lowest_Address = Phys_Addr;

                /* Same for the top address. */
                temp = Phys_Addr + Nb_Bytes -1;

                if (temp > Highest_Address)
                {
                    Highest_Address = temp;
                    if (Verbose_Flag) fprintf(stderr,"Highest_Address: %08X\n",Highest_Address);
                }
                break;

            case 1:
                if (Verbose_Flag) fprintf(stderr,"End of File record\n");
                break;

            case 2:
                /* First_Word contains the offset. It's supposed to be 0000 so
                   we ignore it. */

                /* First extended segment address record ? */
                if (Seg_Lin_Select == NO_ADDRESS_TYPE_SELECTED)
                    Seg_Lin_Select = SEGMENTED_ADDRESS;

                /* Then ignore subsequent extended linear address records */
                if (Seg_Lin_Select == SEGMENTED_ADDRESS)
                {
                    result = sscanf (p, "%4x%2x",&Segment,&temp2);
                    if (result != 2) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

                    if (Verbose_Flag) fprintf(stderr,"Extended Segment Address record: %04X\n",Segment);

                    /* Update the current address. */
                    Phys_Addr = (Segment << 4);
                }
                else
                {
                    fprintf(stderr,"Ignored extended linear address record %d\n", Record_Nb);
                }
                break;

            case 3:
                if (Verbose_Flag) fprintf(stderr,"Start Segment Address record: ignored\n");
                break;

            case 4:
                /* First_Word contains the offset. It's supposed to be 0000 so
                   we ignore it. */

                /* First extended linear address record ? */
                if (Seg_Lin_Select == NO_ADDRESS_TYPE_SELECTED)
                    Seg_Lin_Select = LINEAR_ADDRESS;

                /* Then ignore subsequent extended segment address records */
                if (Seg_Lin_Select == LINEAR_ADDRESS)
                {
                    result = sscanf (p, "%4x%2x",&Upper_Address,&temp2);    //取出基地址(Extended Linear Address)和checksum
                    if (result != 2) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

                    if (Verbose_Flag) fprintf(stderr,"Extended Linear Address record: %04X\n",Upper_Address);

                    /* Update the current address. */
                    Phys_Addr = (Upper_Address << 16);

                    if (Verbose_Flag) fprintf(stderr,"Physical Address: %08X\n",Phys_Addr);
                }
                else
                {
                    fprintf(stderr,"Ignored extended segment address record %d\n", Record_Nb);
                }
                break;

            case 5:
                if (Verbose_Flag) fprintf(stderr,"Start Linear Address record: ignored\n");
                break;

            default:
                if (Verbose_Flag) fprintf(stderr,"Unknown record type: %d at %d\n",Type,Record_Nb);
                break;
            }
        }
    }
    while (!feof (Filin)); 
    /*feof()用来侦测是否读取到了文件尾, 参数stream 为fopen()所返回的文件指针. 如果已读到文件尾则返回非零值, 其他情况返回0.*/

每次读取一行,循环读取,直到文件尾。

申请指定长度的内存(malloc),然后进行第二次遍历,这次的目的是将数据按地址顺序进行排列。

    /* 第二次遍历hex文件, 处理数据 */
    /* Read the file & process the lines. */
    do /* repeat until EOF(Filin) */
    {
        unsigned int i;

        /* Read a line from input file. */
        GetLine(Line,Filin);
        Record_Nb++;

        /* Remove carriage return/line feed at the end of line. */
        i = strlen(Line);

        //fprintf(stderr,"Record: %d; length: %d\n", Record_Nb, i);

        if (--i != 0)
        {
            if (Line[i] == '\n') Line[i] = '\0';

            /* Scan the first two bytes and nb of bytes.
               The two bytes are read in First_Word since its use depend on the
               record type: if it's an extended address record or a data record.
            */
            result = sscanf (Line, ":%2x%4x%2x%s",&Nb_Bytes,&First_Word,&Type,Data_Str);
            if (result != 4) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

            Checksum = Nb_Bytes + (First_Word >> 8) + (First_Word & 0xFF) + Type; //前4个字节累加

            p = (char *) Data_Str;

            /* If we're reading the last record, ignore it. */
            switch (Type)
            {
            /* Data record */
            case 0:
                if (Nb_Bytes == 0)
                {
                    fprintf(stderr,"0 byte length Data record ignored\n");
                    break;
                }

                Address = First_Word;

                if (Seg_Lin_Select == SEGMENTED_ADDRESS)
                    Phys_Addr = (Segment << 4) + Address;
                else
                    /* LINEAR_ADDRESS or NO_ADDRESS_TYPE_SELECTED
                       Upper_Address = 0 as specified in the Intel spec. until an extended address
                       record is read. */
                    if (Address_Alignment_Word)
                        Phys_Addr = ((Upper_Address << 16) + (Address << 1)) + Offset;
                    else
                        Phys_Addr = ((Upper_Address << 16) + Address);

                /* Check that the physical address stays in the buffer's range. */
                if ((Phys_Addr >= Lowest_Address) && (Phys_Addr <= Highest_Address))
                {
                    /* The memory block begins at Lowest_Address */
                    Phys_Addr -= Lowest_Address; /* 计算该条数据记录相对于hex文件起始地址的偏移量 */

                    p = ReadDataBytes(p); /* 根据偏移量将该条记录中的数据写入指定的数组中 */

                    /* Read the Checksum value. */
                    result = sscanf (p, "%2x",&temp2);
                    if (result != 1) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

                    /* Verify Checksum value. */
                    /* 校验和 = 0x100 - 除checksum之外所有字节的累加和 */
                    Checksum = (Checksum + temp2) & 0xFF;
                    VerifyChecksumValue();
                }
                else
                {
                    if (Seg_Lin_Select == SEGMENTED_ADDRESS)
                        fprintf(stderr,"Data record skipped at %4X:%4X\n",Segment,Address);
                    else
                        fprintf(stderr,"Data record skipped at %8X\n",Phys_Addr);
                }

                break;

            /* End of file record */
            case 1:
                /* Simply ignore checksum errors in this line. */
                break;

            /* Extended segment address record */
            case 2:
                /* First_Word contains the offset. It's supposed to be 0000 so
                   we ignore it. */

                /* First extended segment address record ? */
                if (Seg_Lin_Select == NO_ADDRESS_TYPE_SELECTED)
                    Seg_Lin_Select = SEGMENTED_ADDRESS;

                /* Then ignore subsequent extended linear address records */
                if (Seg_Lin_Select == SEGMENTED_ADDRESS)
                {
                    result = sscanf (p, "%4x%2x",&Segment,&temp2);
                    if (result != 2) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

                    /* Update the current address. */
                    Phys_Addr = (Segment << 4);

                    /* Verify Checksum value. */
                    Checksum = (Checksum + (Segment >> 8) + (Segment & 0xFF) + temp2) & 0xFF;
                    VerifyChecksumValue();
                }
                break;

            /* Start segment address record */
            case 3:
                /* Nothing to be done since it's for specifying the starting address for
                   execution of the binary code */
                break;

            /* Extended linear address record */
            case 4:
                /* First_Word contains the offset. It's supposed to be 0000 so
                   we ignore it. */

                if (Address_Alignment_Word) /*默认为false*/
                {
                    sscanf (p, "%4x",&Offset);
                    Offset = Offset << 16;
                    Offset -= Lowest_Address;
                }
                /* First extended linear address record ? */
                if (Seg_Lin_Select == NO_ADDRESS_TYPE_SELECTED)
                    Seg_Lin_Select = LINEAR_ADDRESS;

                /* Then ignore subsequent extended segment address records */
                if (Seg_Lin_Select == LINEAR_ADDRESS)
                {
                    result = sscanf (p, "%4x%2x",&Upper_Address,&temp2);
                    if (result != 2) fprintf(stderr,"Error in line %d of hex file\n", Record_Nb);

                    /* Update the current address. */
                    Phys_Addr = (Upper_Address << 16);

                    /* Verify Checksum value. */
                    Checksum = (Checksum + (Upper_Address >> 8) + (Upper_Address & 0xFF) + temp2)
                               & 0xFF;
                    VerifyChecksumValue();
                }
                break;

            /* Start linear address record */
            case 5:
                /* Nothing to be done since it's for specifying the starting address for
                   execution of the binary code */
                break;
            default:
                fprintf(stderr,"Unknown record type\n");
                break;
            }
        }
    }
    while (!feof (Filin));

最后将数组中的内容输出到文件,即可得到bin文件。

按照上面的思路我用Java写了一个转换类(用在上面提到的ECU下载工具中),感兴趣的同学可以看一看。
其中碰到的坑有必要提一下,由于Hex文件中的数据是采用ASC II码的,而Bin文件中的数据是直接使用的二进制(不存在编码),因此在转换过程中涉及到编码转换。另外还有一点需要提一下,由于Java没有无符号型,如果将读到的数据赋给byte型变量,在调试的过程中使用print输出时会看到乱码(数据溢出byte类型的范围)。

点这里可以跳转到人工智能网站

发表评论