freebsd-skq/lib/libutil/kinfo_getfile.c
ngie 4209db5257 lib/libutil/kinfo_*: style cleanup
- Use nitems(mib) instead of hardcoding mib's length
- Sort sys/ #includes

MFC after:	3 days
2017-01-09 00:47:23 +00:00

78 lines
1.5 KiB
C

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/sysctl.h>
#include <sys/user.h>
#include <stdlib.h>
#include <string.h>
#include "libutil.h"
struct kinfo_file *
kinfo_getfile(pid_t pid, int *cntp)
{
int mib[4];
int error;
int cnt;
size_t len;
char *buf, *bp, *eb;
struct kinfo_file *kif, *kp, *kf;
*cntp = 0;
len = 0;
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_FILEDESC;
mib[3] = pid;
error = sysctl(mib, nitems(mib), NULL, &len, NULL, 0);
if (error)
return (NULL);
len = len * 4 / 3;
buf = malloc(len);
if (buf == NULL)
return (NULL);
error = sysctl(mib, nitems(mib), buf, &len, NULL, 0);
if (error) {
free(buf);
return (NULL);
}
/* Pass 1: count items */
cnt = 0;
bp = buf;
eb = buf + len;
while (bp < eb) {
kf = (struct kinfo_file *)(uintptr_t)bp;
if (kf->kf_structsize == 0)
break;
bp += kf->kf_structsize;
cnt++;
}
kif = calloc(cnt, sizeof(*kif));
if (kif == NULL) {
free(buf);
return (NULL);
}
bp = buf;
eb = buf + len;
kp = kif;
/* Pass 2: unpack */
while (bp < eb) {
kf = (struct kinfo_file *)(uintptr_t)bp;
if (kf->kf_structsize == 0)
break;
/* Copy/expand into pre-zeroed buffer */
memcpy(kp, kf, kf->kf_structsize);
/* Advance to next packed record */
bp += kf->kf_structsize;
/* Set field size to fixed length, advance */
kp->kf_structsize = sizeof(*kp);
kp++;
}
free(buf);
*cntp = cnt;
return (kif); /* Caller must free() return value */
}