micro-utils/sysutils/dmesg.c
2023-11-05 21:42:26 +03:00

66 lines
1.2 KiB
C

#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/klog.h>
#define BUF_SIZE 8196
int main(const int argc, const char **argv) {
unsigned int s_size = 0;
unsigned int n_level = 0;
int i;
for (i = 1; i < argc; i++) {
if (argv[i][0] != '-')
break;
else if (!strncmp(argv[i], "-s=", 3))
s_size = atoi(argv[i] + 3);
else if (!strncmp(argv[i], "-n=", 3))
n_level = atoi(argv[i] + 3);
else if (!strcmp(argv[i], "--help")) {
printf("dmesg [-n=L Set console logging level] [-s=S Buffer Size]\n");
return 0;
}
}
/* Setup */
if (n_level)
if (klogctl(8, NULL, (long)n_level) < 0) {
fprintf(stderr, "dmesg: %s\n", strerror(errno));
return 1;
}
if (!s_size)
s_size = klogctl(10, NULL, 0);
/* Get kernel log */
char *buf = malloc(s_size + 1);
if (buf == NULL) {
fprintf(stderr, "dmesg: malloc failed\n");
return 1;
}
int n = klogctl(3, buf, s_size);
if (n <= 0) {
free(buf);
if (n == 0)
return 0;
fprintf(stderr, "dmesg: %s\n", strerror(errno));
return 1;
}
/* Print */
write(STDOUT_FILENO, buf, n);
putchar('\n');
free(buf);
return 0;
}