linux c语言 readline Linux C代码实现读取配置文件示例

/**

读配置文件示例

注：配置文件必须为unix格式，即\n结尾

*/

#include

#include

#include

#include

#include

// 结构体

struct hostapd_config

{

char iface[16];

uint16_t beacon_int;

uint8_t channel;

char country[3]; /* first two octets: country code as described in

* ISO/IEC 3166-1. Third octet:

* ' ' (ascii 32): all environments

* 'O': Outdoor environemnt only

* 'I': Indoor environment only

*/

};

// 默认值

struct hostapd_config * config_defaults(void)

{

struct hostapd_config *conf = NULL;

conf = (struct hostapd_config *)calloc(1, sizeof(*conf));

if (conf == NULL)

{

return NULL;

}

// set default value

conf->beacon_int = 100;

conf->channel = 1;

return conf;

}

// 根据读取到的信息填充结构体

static int config_defaults(struct hostapd_config *conf, const char *buf, char *pos, int line)

{

if (strcmp(buf, "interface") == 0)

{

strncpy(conf->iface, pos, sizeof(conf->iface));

}

else if (strcmp(buf, "channel") == 0)

{

int val = atoi(pos);

conf->channel = val;

}

else if (strcmp(buf, "beacon_int") == 0)

{

int val = atoi(pos);

conf->beacon_int = val;

}

else if (strcmp(buf, "country_code") == 0)

{

memcpy(conf->country, pos, 2);

conf->country[2] = ' ';

}

// more ...

return 0;

}

//

// 读配置文件

struct hostapd_config* config_read(const char *fname)

{

struct hostapd_config *conf = NULL;

FILE *f = NULL;

char buf[1024] = {0};

char *pos = NULL;

int line = 0;

int errors = 0;

f = fopen(fname, "r");

if (f == NULL)

{

printf("Could not open configuration file '%s' for reading.\n", fname);

return NULL;

}

conf = config_defaults();

if (conf == NULL)

{

fclose(f);

return NULL;

}

while (fgets(buf, sizeof(buf), f))

{

line++;

if (buf[0] == '#')

continue;

pos = buf;

while (*pos != '\0')

{

if (*pos == '\n')

{

*pos = '\0';

break;

}

pos++;

}

if (buf[0] == '\0')

continue;

pos = strchr(buf, '=');

if (pos == NULL) {

printf("Line %d: invalid line '%s'\n", line, buf);

errors++;

continue;

}

*pos = '\0';

pos++;

errors += config_defaults(conf, buf, pos, line);

}

fclose(f);

return conf;

}

/

int main(int argc, char *argv[])

{

const char* conf_file = "foo.conf";

if (argc == 2)

{

conf_file = argv[1];

}

struct hostapd_config *conf = NULL;

conf = config_read(conf_file);

if (conf == NULL)

{

printf("failed to read file: %s\n", conf_file);

return -1;

}

printf("%d %s %s\n", conf->channel, conf->country, conf->iface);

return 0;

}