嵌入式 简单的读取文件并打印指定字符串的值

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <sys/types.h>

#ifdef __DEBUG__
#define msg_print(...) printf(__VA_ARGS__)
#else
#define msg_print(...)
#endif

#define CONF_FILE_PATH "./ipnc_conf.conf"
#define MAX_VALUE_LEN 32
#define ARGV_NOT_EXIST 2
#define ARGV_EXIST 5

#define DEFALUT_JIPNC_ID "jipnc00000000005"
#define DEFALUT_JIPNC_KEY "12345678"
#define DEFALUT_JIPNC_DEVICE_TYPE "30"

int joseph_read_conf(const char *key, char *value);
int joseph_create_conf(const char *id, const char *key, const char *device_type, int flag);

int joseph_create_conf(const char *id, const char *key, const char *device_type, int flag)
{
int conf_fd;
int ret;
char buffer[1024] = {0};

if(flag == ARGV_NOT_EXIST){
conf_fd = open(CONF_FILE_PATH, O_RDONLY | O_EXCL, 777);
msg_print("conf_fd = %d\n",conf_fd);
if(conf_fd > 0){
close(conf_fd);
return 0;
}
}

conf_fd = open(CONF_FILE_PATH, O_WRONLY | O_CREAT | O_TRUNC, 777);
sprintf(buffer, "ipnc_id %s\nipnc_key %s\ndevice_type %s\n", id, key, device_type);
ret = write(conf_fd, buffer, 1024);
msg_print("ret = %d\nbuffer = %s", ret, buffer);

close(conf_fd);
return 0;

}

int joseph_read_conf(const char *key, char *value)
{
FILE *stream = NULL;
char cmd[64] = {0};

if(NULL == key || 0 == strlen(key)){
msg_print("invalid parameter!\n");
return -1;
}

sprintf(cmd, "cat %s | awk '/%s/{print $2}'", CONF_FILE_PATH, key);
msg_print("cmd = %s\n",cmd);

stream = popen(cmd,"r");

if(fread(value, sizeof(char), MAX_VALUE_LEN, stream) <= 0){
pclose(stream);
return -1;
}
strcpy(value + strlen(value) - 1, "\0");
msg_print("%s = %s\n", key, value);

pclose(stream);
system("rm -rf ./ipnc_conf.conf");
return 0;
}

int main(int argc,char *argv[])
{
char value[32] = {0};

//if(argc != 1 || argc != 4)
//{
//	printf("invalid parameter!\n");
//	return -1;
//}
#if 1
if(ARGV_NOT_EXIST == argc)
joseph_create_conf(DEFALUT_JIPNC_ID, DEFALUT_JIPNC_KEY ,DEFALUT_JIPNC_DEVICE_TYPE, ARGV_NOT_EXIST);
else if(ARGV_EXIST == argc)
joseph_create_conf(argv[1], argv[2] ,argv[3], ARGV_EXIST);
else{
printf("invalid parameter!\n");
return -1;
}
#endif
joseph_read_conf("ipnc_id", value);
printf("%s = %s\n", "ipnc_id", value);

return 0;
}