一种简易的嵌入式设备系统日志记录方法

在嵌入式设备应用场景中，系统日志时常可以监控设备软件的运行状态，及时记录问题点以及关键信息，方便开发人员后期定位以及解决问题。
系统日志
本文将讲述一种简易的系统日志记录方法，用于保存设备的系统日志，视具体嵌入式设备情况而定，可存储在MCU内部Flash、外部Flash、EEPROM等，本文采用外部Flash作为示例展开介绍。
思路分析 ?

对于系统日志可以当成文件系统，可以划分为三个重要部分：目录区、参数区、日志区。目录区：根据日期进行归类，记录当天的日志的存储地址、日志索引、日志大小，通过目录可以获取整个日志文件的概况；参数区：存储记录日志写位置、目录项个数、写状态等参数；日志区：这是我们主要的存储区，记录系统的日志，支持环写。这三个区域都需要占用部分内存，可以自行分配大小。
实现的效果如下图所示，设置通过指令可查询到整个日志目录区的概况。
查询系统日志目录：

AT+CATALOG?
LOG_ID：存储日志按日期分类，该ID用于查询对应日期日志,从1开始计数；
LOG_DATE：系统日志存储日期；
LOG_ADDR：系统日志存储外部FLASH地址；
LOG_OFFSET：系统日志存储偏移量（各日期日志大小，单位：字节）。
另外提供移除系统日志（清除日志目录）指令：AT+RMLOG，后面将讲述具体实现。
FLASH内存划分 ?

FLASH内存需要看具体设备进行合理划分，目录区、参数区与日志区实现环形存储，延长擦写寿命。
#define?FLASH_SECTOR_SIZE?????((uint32_t)0x001000)
#define?FLASH_BLOCK_32K_SIZE??((uint32_t)0x008000)
#define?FLASH_BLOCK_64K_SIZE??((uint32_t)0x010000)
#define?SECTOR_MASK???????????(FLASH_SECTOR_SIZE?-?1)????/*扇区掩码?------*/
#define?SECTOR_BASE(addr)?????(addr?&?(~SECTOR_MASK))????/*扇区的基地址?--*/
#define?SECTOR_OFFSET(addr)???(addr?&?SECTOR_MASK)???????/*扇区内的偏移?--*/

#define?BLOCK_32K_BASE(addr)??(addr?&?(~(FLASH_BLOCK_32K_SIZE)))
#define?BLOCK_64K_BASE(addr)??(addr?&?(~(FLASH_BLOCK_64K_SIZE)))

typedef?enum?{
????FLASH_BLOCK_4K??=?0,????/**

	?

	Flash底层实现擦除、读写操作接口，由读者自行实现。

	?
flash_table_t?*get_flash_table(flash_zone_e?zone)
{
????int?i?=?0;
????for?(i?=?0;?i?start_address?||?address?>?flash_table_tmp->end_address)?
????????return?-1;

????return?bsp_spi_flash_erase(address,?block_type);
}

int?flash_write(flash_zone_e?zone,?uint32_t?address,?const?uint8_t*data,?uint32_t?length)
{
????flash_table_t?*flash_table_tmp?=?get_flash_table(zone);
?????
????if?(flash_table_tmp?==?NULL)
????????return?-1;

????if?((address?start_address)?|| ((address?+?length)?>?flash_table_tmp->end_address))
????????return?-1;

????return?bsp_spi_flash_buffer_write(address,?(uint8_t?*)data,?length);
}

int?flash_read(flash_zone_e?zone,?uint32_t?address,?uint8_t*buffer,?uint32_t?length)
{
????flash_table_t?*flash_table_tmp?=?get_flash_table(zone);
??
????if?(flash_table_tmp?==?NULL)
????????return?-1;

????if?((address?start_address)?|| ((address?+?length)?>?flash_table_tmp->end_address))
????????return?-1;
????
????bsp_spi_flash_buffer_read(buffer,?address,?length);
????return?0;
}
? 参数与结构体定义 ?


日志数据存储时间戳，便于问题定位，需要实现RTC接口调用。
typedef?struct?{
????uint16_t??Year;????/*?年份:YYYY?*/
????uint8_t???Month;???/*?月份:MM?*/
????uint8_t???Day;?????/*?日:DD?*/
????uint8_t???Hour;????/*?小时:HH?*/
????uint8_t???Minute;??/*?分钟:MM?*/
????uint8_t???Second;??/*?秒:SS?*/
}time_t;???

int?bsp_rtc_get_time(time_t?*date);

	?

	参数区应当保证数据的正确性，应加入参数校验存储，定义校验结构体。

	?
#define?SYSTEM_LOG_MAGIC_PARAM??0x87654321??/*?日志参数标识符?*/
typedef?struct?{
????uint32_t?magic;??/*?参数标识符?*/
????uint16_t?crc;????/*?校验值?*/
????uint16_t?len;????/*?参数长度?*/
}?single_sav_t;

	?

	参数区需记录当前日志记录的写位置，以及目录项个数，还有日志区和目录区环写状态，并且存储最新时间等等。

	?
/*?日志区参数?*/
typedef?struct?{
????uint32_t?write_pos;?????????????/*?写位置?*/
????uint32_t?catalog_num;???????????/*?目录项个数?*/
????uint8_t??log_cyclic_status;?????/*?系统日志环形写状态?*/???
????uint8_t??catalog_cyclic_status;?/*?日志目录环形写状态?*/
????time_t???log_latest_time;???????/*?存储最新时间?*/
}system_log_t;

/*?目录区参数?*/
typedef?struct?{
????uint32_t?log_id;?????/*?日志索引?*/?
????uint32_t?log_addr;???/*?日志地址?*/
????uint32_t?log_offset;?/*?日志偏移大小，单位：字节?*/
????time_t???log_time;???/*?日志存储时间?*/
}system_catalog_t;

/*?系统日志参数?*/
typedef?struct?{
????single_sav_t?crc_val;
????system_log_t?system_log;
????system_catalog_t?system_catalog;
}sys_log_param_t;

typedef?struct?{
????uint8_t??system_log_print_enable;?/*?系统日志打印使能?*/
????uint16_t?system_log_print_id;?????/*?打印指定id系统日志?*/
????uint32_t?system_log_param_addr;???/*?当前日志写地址?*/
}?sys_ram_t;

sys_ram_t?SysRam;
sys_log_param_t?SysLogParam;

sys_ram_t?*gp_sys_ram?=?&SysRam;
sys_log_param_t?*gp_sys_log?=?&SysLogParam;
? 实现接口说明 ?


CRC校验接口，可以自定义实现。
/*?16位CRC校验高位表?*/
static?const?uint8_t?auchCRCHi[]?=?{
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,

0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40,0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,
0x00,0xc1,0x81,0x40,0x01,0xc0,0x80,0x41,0x01,0xc0,0x80,0x41,0x00,0xc1,0x81,0x40
};

/*?16位CRC校验低位表?*/
static?const?uint8_t?auchCRCLo[]?=?{
0x00,0xc0,0xc1,0x01,0xc3,0x03,0x02,0xc2,0xc6,0x06,0x07,0xc7,0x05,0xc5,0xc4,0x04,
0xcc,0x0c,0x0d,0xcd,0x0f,0xcf,0xce,0x0e,0x0a,0xca,0xcb,0x0b,0xc9,0x09,0x08,0xc8,
0xd8,0x18,0x19,0xd9,0x1b,0xdb,0xda,0x1a,0x1e,0xde,0xdf,0x1f,0xdd,0x1d,0x1c,0xdc,
0x14,0xd4,0xd5,0x15,0xd7,0x17,0x16,0xd6,0xd2,0x12,0x13,0xd3,0x11,0xd1,0xd0,0x10,
0xf0,0x30,0x31,0xf1,0x33,0xf3,0xf2,0x32,0x36,0xf6,0xf7,0x37,0xf5,0x35,0x34,0xf4,
0x3c,0xfc,0xfd,0x3d,0xff,0x3f,0x3e,0xfe,0xfa,0x3a,0x3b,0xfb,0x39,0xf9,0xf8,0x38,
0x28,0xe8,0xe9,0x29,0xeb,0x2b,0x2a,0xea,0xee,0x2e,0x2f,0xef,0x2d,0xed,0xec,0x2c,
0xe4,0x24,0x25,0xe5,0x27,0xe7,0xe6,0x26,0x22,0xe2,0xe3,0x23,0xe1,0x21,0x20,0xe0,

0xa0,0x60,0x61,0xa1,0x63,0xa3,0xa2,0x62,0x66,0xa6,0xa7,0x67,0xa5,0x65,0x64,0xa4,
0x6c,0xac,0xad,0x6d,0xaf,0x6f,0x6e,0xae,0xaa,0x6a,0x6b,0xab,0x69,0xa9,0xa8,0x68,
0x78,0xb8,0xb9,0x79,0xbb,0x7b,0x7a,0xba,0xbe,0x7e,0x7f,0xbf,0x7d,0xbd,0xbc,0x7c,
0xb4,0x74,0x75,0xb5,0x77,0xb7,0xb6,0x76,0x72,0xb2,0xb3,0x73,0xb1,0x71,0x70,0xb0,
0x50,0x90,0x91,0x51,0x93,0x53,0x52,0x92,0x96,0x56,0x57,0x97,0x55,0x95,0x94,0x54,
0x9c,0x5c,0x5d,0x9d,0x5f,0x9f,0x9e,0x5e,0x5a,0x9a,0x9b,0x5b,0x99,0x59,0x58,0x98,
0x88,0x48,0x49,0x89,0x4b,0x8b,0x8a,0x4a,0x4e,0x8e,0x8f,0x4f,0x8d,0x4d,0x4c,0x8c,
0x44,0x84,0x85,0x45,0x87,0x47,0x46,0x86,0x82,0x42,0x43,0x83,0x41,0x81,0x80,0x40
};

/*?实现crc功能函数?*/
static?uint16_t?CRC16(uint8_t*?puchMsg,?uint16_t?usDataLen)
{
????uint8_t??uchCRCHi?=?0xff;
????uint8_t??uchCRCLo?=?0xff;
????uint16_t?uIndex;
????
????while(usDataLen?--)?
????{
????????uIndex?=?uchCRCHi^*(puchMsg?++);
????????uchCRCHi?=?uchCRCLo^auchCRCHi[uIndex];
????????uchCRCLo?=?auchCRCLo[uIndex];
????}
????
????return?uchCRCHi?<

	?

	保存系统日志参数，每实现写日志操作后都需要保存当前的参数值，防止意外丢失。

	?
void?save_system_log_param(void)
{
????uint32_t?i?=?0;
????uint32_t?addr?=?0;
????uint32_t?remainbyte?=?0;
????uint32_t?start_addr;
????int?len?=?sizeof(sys_log_param_t);
????uint8_t?*pdata?=?(uint8_t?*)&SysLogParam;
????flash_table_t?*flash_tmp?=?get_flash_table(FLASH_SYSLOG_PARA_ZONE);
????
????/*?校验参数?*/
????gp_sys_log->crc_val.magic?=?SYSTEM_LOG_MAGIC_PARAM;
????gp_sys_log->crc_val.len?=?sizeof(sys_log_param_t)?-?sizeof(single_sav_t);
????gp_sys_log->crc_val.crc?=?CRC16(&pdata[sizeof(single_sav_t)],?gp_sys_log->crc_val.len);

????start_addr?=?gp_sys_ram->system_log_param_addr;
????/*?剩余内存不够写，则重新从起始地址开始写，实现环形存储功能??*/
????if?((start_addr?+?len)?>?flash_tmp->end_address)?
????{?
????????start_addr?=?flash_tmp->start_address;
????}
????gp_sys_ram->system_log_param_addr?=?start_addr?+?len;
????/*?首地址存储，擦除整个系统日志参数存储区，如果划分的内存较大，可能出现第一次擦写等待时间较长，
???????但实际应用嵌入式设备应该不会占用太多的内存存储系统日志，只当为辅助使用，有额外应用可自行实现?*/
????if?(flash_tmp->start_address?==?start_addr)?
????{
????????/*for?(i?=?flash_tmp->start_address;?i?end_address;?i+=?FLASH_SECTOR_SIZE)?
????????????flash_erase(FLASH_SYSLOG_PARA_ZONE,?SECTOR_BASE(i),?FLASH_BLOCK_4K);
????????*/
????????addr?=?flash_tmp->start_address;
????????do?
????????{
????????????if?((addr?+?FLASH_BLOCK_64K_SIZE)?<=?flash_tmp->end_address)?
????????????{
????????????????flash_erase(FLASH_SYSLOG_PARA_ZONE,?BLOCK_64K_BASE(i),?FLASH_BLOCK_64K);
????????????????addr?+=?FLASH_BLOCK_64K_SIZE;
????????????}?
????????????else?if?((addr?+?FLASH_BLOCK_32K_SIZE)?<=?flash_tmp->end_address)?
????????????{
????????????????flash_erase(FLASH_SYSLOG_PARA_ZONE,?BLOCK_32K_BASE(i),?FLASH_BLOCK_32K);
????????????????addr?+=?FLASH_BLOCK_32K_SIZE;
????????????}?
????????????else?if?((addr?+?FLASH_SECTOR_SIZE)?<=?flash_tmp->end_address)?
????????????{
????????????????flash_erase(FLASH_SYSLOG_PARA_ZONE,?SECTOR_BASE(i),?FLASH_BLOCK_4K);
????????????????addr?+=?FLASH_SECTOR_SIZE;
????????????}?
????????????else?
????????????{
????????????????break;
????????????}
????????}?
????????while?(addr?end_address);?
????}

????remainbyte?=?FLASH_SECTOR_SIZE?-?(start_addr?%?FLASH_SECTOR_SIZE);
????if?(remainbyte?>?len)?
????{
????????remainbyte?=?len;
????}
????while?(1)?
????{
????????flash_write(FLASH_SYSLOG_PARA_ZONE,?start_addr,?pdata,?remainbyte);
????????if?(remainbyte?==?len)?
????????{
????????????break;
????????}?
????????else?
????????{
????????????pdata?+=?remainbyte;
????????????start_addr?+=?remainbyte;
????????????len?-=?remainbyte;
????????????remainbyte?=?(len?>?FLASH_SECTOR_SIZE)???FLASH_SECTOR_SIZE?:?len;
????????}
????}
}

	?

	导入系统日志默认参数接口，初始化默认参数或者移除日志。

	?
void?load_system_log_default_param(void)
{
????/*?系统日志默认参数?*/
????/*?目录环写状态标志?*/
????gp_sys_log->system_log.catalog_cyclic_status?=?0x00;
????/*?目录项个数?*/
????gp_sys_log->system_log.catalog_num?=?0;
????/*?日志环写标志?,?1:环写状态?*/
????gp_sys_log->system_log.log_cyclic_status?=?0;
????/*?设置默认值，实际会重新从RTC获取最新时间?*/
????gp_sys_log->system_log.log_latest_time.Year?=?2019;
????gp_sys_log->system_log.log_latest_time.Month?=?5;
????gp_sys_log->system_log.log_latest_time.Day?=?8;
????gp_sys_log->system_log.log_latest_time.Hour?=?13;
????gp_sys_log->system_log.log_latest_time.Minute?=?14;
????gp_sys_log->system_log.log_latest_time.Second?=?10;
????/*?日志写位置从0开始?*/
????gp_sys_log->system_log.write_pos?=?0;
????
????gp_sys_log->system_catalog.log_addr?=?0;
????gp_sys_log->system_catalog.log_id?=?0;
????gp_sys_log->system_catalog.log_offset?=?0;
????gp_sys_log->system_catalog.log_time.Year?=?2019;
????gp_sys_log->system_catalog.log_time.Month?=?5;
????gp_sys_log->system_catalog.log_time.Day?=?8;
????gp_sys_log->system_catalog.log_time.Hour?=?12;
????gp_sys_log->system_catalog.log_time.Minute?=?12;
????gp_sys_log->system_catalog.log_time.Second?=?14;
????
????gp_sys_log->crc_val.magic?=?SYSTEM_LOG_MAGIC_PARAM;

????/*?导入默认参数后进行保存?*/
????save_system_log_param();
}

	?

	设备开机或者复位都会进行导入系统日志参数操作，恢复日志读写参数，参数区为频繁读写操作区域，每一次写操作都会进行一次偏移，有效的导入参数方法是从参数区结束地址到起始地址进行扫描，扫描不到合法的参数则会导入默认日志参数。

	?
/*?参数初始化，在终端启动时调用?*/
int?load_system_log_param(void)
{
????uint32_t?i?=?0;
????single_sav_t?psav;
????uint32_t?end_addr;
????uint32_t?interal?=?sizeof(sys_log_param_t);
????int?data_len?=?sizeof(sys_log_param_t)?-?sizeof(single_sav_t);
????uint8_t?*pram?=?(uint8_t?*)&SysLogParam;
????flash_table_t?*flash_tmp?=?get_flash_table(FLASH_SYSLOG_PARA_ZONE);
????
????end_addr?=flash_tmp->end_address?-?(flash_tmp->end_address?-?flash_tmp->start_address)?%?interal;
????for?(i?=?end_addr?-?interal;?i?>?flash_tmp->start_address;?i?-=?interal)?
????{
????????flash_read(FLASH_SYSLOG_PARA_ZONE,?i,?(uint8_t?*)&psav,?sizeof(single_sav_t));
????????if?((psav.magic?==?SYSTEM_LOG_MAGIC_PARAM)?&&?(psav.len?==data_len))?
????????{???
????????????flash_read(FLASH_SYSLOG_PARA_ZONE,?i?+?sizeof(single_sav_t),?&pram[sizeof(single_sav_t)],?data_len);
????????????if?(psav.crc?!=?CRC16(&pram[sizeof(single_sav_t)],?data_len))?
????????????????continue;
????????????gp_sys_ram->system_log_param_addr?=?i;
????????????log_info("Load?System?Log?Param?Addr[0x%08x]!",?gp_sys_ram->system_log_param_addr);
????????????return?0;
????????}
????}
????
????/*?扫描不到合法的参数，导入默认系统日志参数?*/
????load_system_log_default_param();
????/*?获取日志写地址?*/
????gp_sys_ram->system_log_param_addr?=?flash_tmp->start_address;
????log_info("Load?System?Log?Param?Addr(Default)[0x%08x]!",?gp_sys_ram->system_log_param_addr);
????return?1;
}

	?

	读写系统日志目录接口，读写指定日志索引目录信息。实际实现会定义最新的目录信息存储在日志参数区，当日期发生改变，则表示当前目录信息已经完结，将最新的目录信息录入日志目录区保存，最多每天写入一次目录区。

	?
/*?读取日志目录区指定日志索引目录信息?*/
int?system_catalog_read(system_catalog_t?*catalog,?uint32_t?id)
{
????uint32_t?addr;
????int?rlen?=?sizeof(system_catalog_t);
????uint8_t?*pbuf?=?(uint8_t?*)catalog;
????flash_table_t?*flash_tmp?=?get_flash_table(FLASH_CATALOG_ZONE);

????if?(0?==?id)?
????????return?-1;
????addr?=?flash_tmp->start_address?+?(rlen?*?(id?-?1));
????if?(addr?>?flash_tmp->end_address)?
????????return?-1;
????????
????return?flash_read(FLASH_CATALOG_ZONE,?addr,?pbuf,?rlen);
}

/*?写日志目录区目录信息?*/
int?system_catalog_write(system_catalog_t?*catalog,?uint32_t?id)
{
????uint32_t?start_offset;
????uint32_t?start_addr;
????uint32_t?start_base;
????uint32_t?remainbyte;
????int?wlen?=?sizeof(system_catalog_t);
????uint8_t?*pdata?=?(uint8_t?*)catalog;
????flash_table_t?*flash_tmp?=?get_flash_table(FLASH_CATALOG_ZONE);
????
????if?(0?==?id)?
????????return?-1;
????start_addr?=?flash_tmp->start_address?+?wlen?*?(id?-?1);
????if?((start_addr?+?wlen)?>?flash_tmp->end_address)?
????{
????????start_addr?=?flash_tmp->start_address;
????}
????
????/*?本扇区剩余空间大小?*/
????remainbyte?=?FLASH_SECTOR_SIZE?-?(start_addr?%?FLASH_SECTOR_SIZE);
????/*?写入数据长度小于本扇区剩余长度，直接写入?*/
????if?(remainbyte?>?wlen)?
????{
????????remainbyte?=?wlen;
????}
????/*?写目录次数不会太频繁，视具体情况改写操作实现?*/
????while?(1)?
????{
????????start_base?=?SECTOR_BASE(start_addr);
????????start_offset?=?SECTOR_OFFSET(start_addr);
????????flash_read(FLASH_CATALOG_ZONE,?start_base,?sector_buf,?FLASH_SECTOR_SIZE);
????????flash_erase(FLASH_CATALOG_ZONE,?start_base,?FLASH_BLOCK_4K);
????????memcpy((char?*)§or_buf[start_offset],?pdata,?remainbyte);
????????flash_write(FLASH_CATALOG_ZONE,?start_base,?sector_buf,?FLASH_SECTOR_SIZE);
????????if?(remainbyte?==?wlen)?
????????{
????????????break;
????????}?
????????else?
????????{
????????????pdata?+=?remainbyte;
????????????start_addr?+=?remainbyte;
????????????wlen?-=?remainbyte;
????????????remainbyte?=?(wlen?>?FLASH_SECTOR_SIZE)???FLASH_SECTOR_SIZE?:?wlen;
????????}
????}
????
????return?0;
}

	?

	打印系统日志目录区信息，可实现通过指令查询到目录区信息。

	?
int?system_catalog_all_print(void)
{
????int?i?=?0;
????system_catalog_t?catalog;

????printf("System?Log?Command?Information:
");
????printf("Query?Specifies?Log?:?AT+CATALOG=
");
????printf("Query?All?Log?:?AT+CATALOG=<0>

");
????printf("Query?All?System?Catalog:
");
????printf("LOG_ID??LOG_DATE??LOG_ADDR??LOG_OFFSET?
");
????for?(i?=?0;?i?system_log.catalog_num;?i++)??
????{
????????/*?当前最新目录信息?*/??
????????if?(i?==?(gp_sys_log->system_catalog.log_id?-?1))?
????????{
????????????catalog?=?gp_sys_log->system_catalog;?/*?获取当前最新目录信息?*/
????????}?
????????else?
????????{
????????????system_catalog_read(&catalog,?i?+?1);
????????}
????????printf("%d??%04d-%02d-%02d??0x%08X??%d?
",?
????????????catalog.log_id,?catalog.log_time.Year,?catalog.log_time.Month,?catalog.log_time.Day,?
????????????catalog.log_addr,?catalog.log_offset);
????????memset((char?*)&catalog,?0,?sizeof(system_catalog_t));
????}
????return?0;
}

	?

	读取指定日志目录索引信息接口，可指定日志索引或者读取全部日志数据。

	?
int?system_log_task(int?argc)
{
????int?rlen?=?0;
????uint32_t?offset,?start_addr,?end_addr;
????system_catalog_t?catalog;
????flash_table_t?*flash_tmp?=get_flash_table(FLASH_SYSLOG_ZONE);
????
????if?(0?==?gp_sys_ram->system_log_print_enable)?
????????return?1;

????gp_sys_ram->system_log_print_enable?=?0x00;
????if?(gp_sys_ram->system_log_print_id?==?ALL_LOG_PRINT)?
????{
????????/*?log回环写标志,打印整个LOG存储区?*/
????????if?(0x01?==?gp_sys_log->system_log.log_cyclic_status)?
????????{?
????????????start_addr?=?flash_tmp->start_address;
????????????end_addr?=?flash_tmp->end_address;
????????????offset?=?end_addr?-?start_addr;
????????}?
????????else?
????????{
????????????start_addr?=?flash_tmp->start_address;
????????????end_addr?=?start_addr?+?gp_sys_log->system_log.write_pos;
????????????offset?=?gp_sys_log->system_log.write_pos;
????????}
????}?
????else?
????{???/*?读取指定ID日志?*/
????????if?(gp_sys_ram->system_log_print_id?==?gp_sys_log->system_catalog.log_id)?
????????{
????????????catalog?=?gp_sys_log->system_catalog;
????????}?
????????else?
????????{
????????????system_catalog_read(&catalog,?gp_sys_ram->system_log_print_id);
????????}
????????start_addr?=?catalog.log_addr;
????????offset?=?catalog.log_offset;
????}?

????if?(0?==?offset)
????????return?1;

????while?(1)?
????{
????????rlen?=?(offset?>?512)???512?:?offset;
????????system_log_read(sector_buf,?start_addr,?rlen);
????????HAL_Delay(80);
????????/*?目录信息通过调式串口打印?*/
????????bsp_debug_send(sector_buf,?rlen);
????????start_addr?+=?rlen;
????????offset?-=?rlen;
????????if?(0?==?offset)?
????????????break;
????}
????return?0;
}

	?

	存储系统日志接口，实现更新存储日期，当写位置为扇区地址，则擦除一个扇区作为存储日志，这样避免每写一次就擦除一次。

	?
int?system_log_write(uint8_t?*wbuf,?int?wlen)
{
????uint32_t?start_addr;
????uint8_t?*pdata?=?wbuf;
????uint32_t?remainbyte;
????int?system_catalog_max_id;
????flash_table_t?*flash_tmp?=get_flash_table(FLASH_SYSLOG_ZONE);
????
????/*?计算目录区的最大存储目录项个数?*/
????system_catalog_max_id?=?((flash_tmp->end_address?-?flash_tmp->start_address)?/?sizeof(system_catalog_t));
????start_addr?=?flash_tmp->start_address?+?gp_sys_log->system_log.write_pos;
????/*?存储数据地址大于规划内存地址范围处理?*/
????if?((start_addr?+?wlen)?>?flash_tmp->end_address)?
????{?
????????start_addr?=?flash_tmp->start_address;
????????/*?写位置偏移量重置?*/
????????gp_sys_log->system_log.write_pos?=?0;
????????/*?LOG回环存储标志置位?*/
????????gp_sys_log->system_log.log_cyclic_status?=?0x01;?
????}
????/*?写位置偏移?*/
????gp_sys_log->system_log.write_pos?+=?wlen;?

????if?((gp_sys_log->system_log.log_latest_time.Year?!=?gp_sys_log->system_catalog.log_time.Year)?||
????????(gp_sys_log->system_log.log_latest_time.Month?!=?gp_sys_log->system_catalog.log_time.Month)?||
????????(gp_sys_log->system_log.log_latest_time.Day?!=?gp_sys_log->system_catalog.log_time.Day))?
????{
????????/*?日期改变，记录目录信息，当log_id为0，则不写入?*/
????????system_catalog_write(&gp_sys_log->system_catalog,?gp_sys_log->system_catalog.log_id);
????????/*?记录存储日期?*/
????????gp_sys_log->system_catalog.log_time?=?gp_sys_log->system_log.log_latest_time;
????????
????????if?((gp_sys_log->system_catalog.log_id?+?1)?>=?system_catalog_max_id)?
????????{
????????????gp_sys_log->system_log.catalog_num?=?system_catalog_max_id;?/*?目录循环写，目录数应为最大?*/
????????????gp_sys_log->system_log.catalog_cyclic_status?=?1;?/*?目录回环写标志?*/
????????}?
????????else?
????????{
????????????if?(0?==?gp_sys_log->system_log.catalog_cyclic_status)?
????????????{
????????????????/*?获取目录数?*/
????????????????gp_sys_log->system_log.catalog_num?=?gp_sys_log->system_catalog.log_id?+?1;?
????????????}
????????}
????????
????????/*?存储最新目录项信息?*/
????????gp_sys_log->system_catalog.log_id?=?(gp_sys_log->system_catalog.log_id?+?1)?%?system_catalog_max_id;
????????gp_sys_log->system_catalog.log_addr?=?start_addr;
????????gp_sys_log->system_catalog.log_offset?=?wlen;?
????}?
????else?
????{
????????gp_sys_log->system_catalog.log_offset?+=?wlen;?
????}
????
????/*?写位置为存储起始地址并且不为扇区首地址?*/
????if?((flash_tmp->start_address?==?start_addr)?&&?(SECTOR_OFFSET(flash_tmp->start_address)))
????{
????????flash_read(FLASH_SYSLOG_ZONE,?SECTOR_BASE(start_addr),?sector_buf,?FLASH_SECTOR_SIZE);
????????flash_erase(FLASH_SYSLOG_ZONE,?SECTOR_BASE(start_addr),?FLASH_BLOCK_4K);
????????/*?将扇区头部至起始地址区间的数据回写?*/
????????flash_write(FLASH_SYSLOG_ZONE,?SECTOR_BASE(start_addr),?§or_buf[0],?SECTOR_OFFSET(start_addr));?
????}
????/*?写位置为扇区首地址，则擦除一个扇区的存储区????*/
????if?(0?==?SECTOR_OFFSET(start_addr))?
????{
????????flash_erase(FLASH_SYSLOG_ZONE,?SECTOR_BASE(start_addr),?FLASH_BLOCK_4K);
????}

????/*?本扇区剩余空间大小?*/
????remainbyte?=?FLASH_SECTOR_SIZE?-?(start_addr?%?FLASH_SECTOR_SIZE);
????/*?写入数据长度小于本扇区剩余长度，直接写入?*/
????if?(remainbyte?>?wlen)?
????{
????????remainbyte?=?wlen;
????}
????while?(1)?
????{
????????flash_write(FLASH_SYSLOG_ZONE,?start_addr,?pdata,?remainbyte);
????????if?(remainbyte?==?wlen)?
????????{
????????????break;
????????}?
????????else?
????????{
????????????pdata?+=?remainbyte;
????????????start_addr?+=?remainbyte;
????????????wlen?-=?remainbyte;
????????????remainbyte?=?(wlen?>?FLASH_SECTOR_SIZE)???FLASH_SECTOR_SIZE?:?wlen;
????????????/*?扇区首地址则擦除整个扇区，该扇区数据不保存?*/
????????????if?(0?==?SECTOR_OFFSET(start_addr))?
????????????{
????????????????flash_erase(FLASH_SYSLOG_ZONE,?SECTOR_BASE(start_addr),?FLASH_BLOCK_4K);
????????????}
????????}
????}

????/*?环形存储参数?*/
????save_system_log_param();
????return?0;
}
? 系统调试对接 ?


为了更好记录系统日志，将应用调试等级结合一块，实现记录错误调试信息以及需要保存的关键信息。定义的调试等级有：关闭调试等级、错误调试等级、警告调试等级、关键调试等级、debug调试等级，而LOG_RECORD_LEVEL将主动保存日志并输出信息，LOG_ERROR_LEVEL会存储对应的日志信息，但需要根据应用调试等级输出信息。设置与读取应用调试等级由读者自行定义。
#define?LOG_CLOSE_LEVEL??0x00??/*?关闭调试信息?*/
#define?LOG_ERROR_LEVEL??0x01??/*?错误调试信息?*/
#define?LOG_WARN_LEVEL???0x02??/*?警告调试信息?*/
#define?LOG_INFO_LEVEL???0x03??/*?关键调试信息?*/
#define?LOG_DEBUG_LEVEL??0x04??/*?debug调试信息?*/
#define?LOG_RECORD_LEVEL?0x10??/*?保存日志并输出信息?*/?
#define?LOG_PRINT_LEVEL??0xff

#define?SET_LOG_LEVEL(LEVEL)?(gp_sys_param->system_print_level?=?LEVEL)
#define?GET_LOG_LEVEL()??????(gp_sys_param->system_print_level)

#define?log_debug(fmt,?args...)??log_format(LOG_DEBUG_LEVEL,?fmt,?##args)
#define?log_info(fmt,?args...)???log_format(LOG_INFO_LEVEL,?fmt,?##args)
#define?log_warn(fmt,?args...)???log_format(LOG_WARN_LEVEL,?fmt,?##args)
#define?log_error(fmt,?args...)??log_format(LOG_ERROR_LEVEL,?fmt,?##args)
#define?log_record(fmt,?args...)?log_format(LOG_RECORD_LEVEL,?fmt,?##args)
#define?printf(fmt,?args...)?????log_format(LOG_PRINT_LEVEL,?fmt,?##args)

typedef?struct?
{
????int?level;
????char?*fmt_str;
}system_print_fmt_t;

system_print_fmt_t?system_print_fmt_list[]?=?
{
????{?.level?=?LOG_ERROR_LEVEL,??.fmt_str?=?":"},
????{?.level?=?LOG_WARN_LEVEL,???.fmt_str?=?":"},
????{?.level?=?LOG_INFO_LEVEL,???.fmt_str?=?":"},
????{?.level?=?LOG_DEBUG_LEVEL,??.fmt_str?=?":"},
????{?.level?=?LOG_RECORD_LEVEL,?.fmt_str?=?":"},
};

int?log_format(uint8_t?level,?const?char?*fmt,?...)
{
????#define?TIME_PREFIX_SIZE??(21)
????#define?PRINT_MAX_SIZE????(1024?+?TIME_PREFIX_SIZE)
????
????va_list?args;
????int?num?=?0,?i?=?0,?fmt_index?=?0;
????int?fmt_str_len?=?0,?ret?=?-1;
????int?file_str_len?=?0,?line_str_len?=?0;
????char?line_buf[20]?=?{0};
????static?char?buf[PRINT_MAX_SIZE];
????static?QueueHandle_t?sem?=?NULL;
????time_t?time?=?{0};
????
????/*?针对os系统?*/
????if?(NULL?==?sem)?
????{
??????????sem?=?xSemaphoreCreateCounting(1,?1);?/*?always?think?of?success?*/
????}
????
????xSemaphoreTake(sem,?portMAX_DELAY);

????ret?=?-1;
????fmt_str_len?=?0;
????if?(level?!=?LOG_PRINT_LEVEL)?
????{
????????if?((GET_LOG_LEVEL()??SYSTEM_PRINT_FMT_LIST_MAX)?
????????{
????????????goto?exit_end;
????????}

????????fmt_str_len?=?strlen(system_print_fmt_list[fmt_index].fmt_str);
????????strncpy((char?*)&buf[TIME_PREFIX_SIZE],?system_print_fmt_list[fmt_index].fmt_str,?fmt_str_len);
????}

????va_start(args,?fmt);
????num?=?vsnprintf((char?*)&buf[fmt_str_len?+?TIME_PREFIX_SIZE],?PRINT_MAX_SIZE?-?fmt_str_len?-?TIME_PREFIX_SIZE?-?2,?fmt,?args);
????va_end(args);

????if?(num?<=?0)?
????{
????????goto?exit_end;
????}

????if?(level?!=?LOG_PRINT_LEVEL)?
????{
????????num?+=?fmt_str_len;
????????buf[num?+?TIME_PREFIX_SIZE]?=?'
';
????????buf[num?+?TIME_PREFIX_SIZE?+?1]?=?'
';
????????num?+=?2;
????}

????if?((GET_LOG_LEVEL()?system_log.log_latest_time?=?time;
????????system_log_write((uint8_t?*)buf,?num?+?TIME_PREFIX_SIZE);
????}?

exit_end:
????xSemaphoreGive(sem);
????return?ret;
}

	?

	结语 ?


	本文提供的一种简易嵌入式设备系统日志记录方法，代码量不多，实现简单，针对不同的设备需要合理规划内存使用，根据软件运行状态，合适加入调试信息并保存对应的日志信息，方便开发人员了解系统或软件运行状况，协助开发分析数据资源从而更好完善系统，提高定位以及解决问题的效果。

	　　审核编辑：汤梓红