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/*
* sysctl - sysctl set/get helpers
* Subject to the GPL, version 2.
*/
#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>
#include "built_in.h"
#define SYS_PATH "/proc/sys/"
int sysctl_set_int(const char *file, int value)
{
char path[PATH_MAX];
char str[64];
ssize_t ret;
int fd;
strncpy(path, SYS_PATH, PATH_MAX);
strncat(path, file, PATH_MAX - sizeof(SYS_PATH) - 1);
fd = open(path, O_WRONLY);
if (unlikely(fd < 0))
return -1;
ret = snprintf(str, 63, "%d", value);
if (ret < 0) {
close(fd);
return -1;
}
ret = write(fd, str, strlen(str));
close(fd);
return ret <= 0 ? -1 : 0;
}
int sysctl_get_int(const char *file, int *value)
{
char path[PATH_MAX];
char str[64];
ssize_t ret;
int fd;
strncpy(path, SYS_PATH, PATH_MAX);
strncat(path, file, PATH_MAX - sizeof(SYS_PATH) - 1);
fd = open(path, O_RDONLY);
if (fd < 0)
return -1;
ret = read(fd, str, sizeof(str));
if (ret > 0) {
*value = atoi(str);
ret = 0;
} else {
ret = -1;
}
close(fd);
return ret;
}
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