Re: [take13 1/3] kevent: Core files.

From: Evgeniy Polyakov
Date: Wed Aug 23 2006 - 09:44:39 EST


On Wed, Aug 23, 2006 at 05:27:53PM +0400, Evgeniy Polyakov (johnpol@xxxxxxxxxxx) wrote:
> One can find it in archive on homepage
> http://tservice.net.ru/~s0mbre/old/?section=projects&item=kevent
> or attached.

Now it is really attached.

--
Evgeniy Polyakov
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/mman.h>

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>

#include <linux/unistd.h>
#include <linux/types.h>

#define PAGE_SIZE 4096
#include <linux/ukevent.h>

#define _syscall4(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4) \
type name (type1 arg1, type2 arg2, type3 arg3, type4 arg4) \
{\
return syscall(__NR_##name, arg1, arg2, arg3, arg4);\
}

#define _syscall5(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4, \
type5,arg5) \
type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5) \
{\
return syscall(__NR_##name, arg1, arg2, arg3, arg4, arg5);\
}

#define _syscall6(type,name,type1,arg1,type2,arg2,type3,arg3,type4,arg4, \
type5,arg5,type6,arg6) \
type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5, type6 arg6) \
{\
return syscall(__NR_##name, arg1, arg2, arg3, arg4, arg5, arg6);\
}

_syscall4(int, kevent_ctl, int, arg1, unsigned int, argv2, unsigned int, argv3, void *, argv4);
_syscall6(int, kevent_get_events, int, arg1, unsigned int, argv2, unsigned int, argv3, __u64, argv4, void *, argv5, unsigned, arg6);

#define ulog(f, a...) fprintf(stderr, f, ##a)
#define ulog_err(f, a...) ulog(f ": %s [%d].\n", ##a, strerror(errno), errno)

static void usage(char *p)
{
ulog("Usage: %s -t type -e event -o oneshot -p path -n wait_num -f kevent_file -h\n", p);
}

static int get_id(int type, char *path)
{
int ret = -1;

switch (type) {
case KEVENT_TIMER:
ret = 3000;
break;
case KEVENT_INODE:
ret = open(path, O_RDONLY);
break;
}

return ret;
}

static void *evtest_mmap(int fd, off_t *offset, unsigned int number)
{
void *start, *ptr;
off_t o = *offset;

start = NULL;

ptr = mmap(start, PAGE_SIZE*number, PROT_READ, MAP_SHARED, fd, o*PAGE_SIZE);
if (ptr == MAP_FAILED) {
ulog_err("Failed to mmap: start: %p, number: %u, offset: %lu", start, number, o);
return NULL;
}

printf("mmap: ptr: %p, start: %p, number: %u, offset: %lu.\n", ptr, start, number, o);
*offset = o + number;
return ptr;
}

int main(int argc, char *argv[])
{
int ch, fd, err, type, event, oneshot, wait_num, number;
unsigned int i, num, old_idx;
char *path, *file;
char buf[4096];
struct ukevent *uk;
struct kevent_mring *ring;
off_t offset;

path = NULL;
type = event = -1;
oneshot = 0;
wait_num = 10;
offset = 0;
number = 1;
old_idx = 0;
file = "/dev/kevent";

while ((ch = getopt(argc, argv, "f:p:t:e:o:n:h")) > 0) {
switch (ch) {
case 'f':
file = optarg;
break;
case 'n':
wait_num = atoi(optarg);
break;
case 'p':
path = optarg;
break;
case 't':
type = atoi(optarg);
break;
case 'e':
event = atoi(optarg);
break;
case 'o':
oneshot = atoi(optarg);
break;
default:
usage(argv[0]);
return -1;
}
}

if (event == -1 || type == -1 || (type == KEVENT_INODE && !path)) {
ulog("You need at least -t -e parameters and -p for inode notifications.\n");
usage(argv[0]);
return -1;
}

fd = open(file, O_RDWR);
if (fd == -1) {
ulog_err("Failed create kevent control block using file %s", file);
return -1;
}

ring = evtest_mmap(fd, &offset, number);
if (!ring)
return -1;

memset(buf, 0, sizeof(buf));

num = 1;
for (i=0; i<num; ++i) {
uk = (struct ukevent *)buf;
uk->event = event;
uk->type = type;
if (oneshot)
uk->req_flags |= KEVENT_REQ_ONESHOT;
uk->user[0] = i;
uk->id.raw[0] = get_id(uk->type, path);

err = kevent_ctl(fd, KEVENT_CTL_ADD, 1, uk);
if (err < 0) {
ulog_err("Failed to perform control operation: type=%d, event=%d, oneshot=%d", type, event, oneshot);
close(fd);
return err;
}
if (err) {
ulog("%d: ret_flags: 0x%x, ret_data: %u %d.\n", i, uk->ret_flags, uk->ret_data[0], (int)uk->ret_data[1]);
}
}

while (1) {
err = kevent_get_events(fd, 1, wait_num, 10000000000, buf, 0);
if (err < 0) {
ulog_err("Failed to perform control operation: type=%d, event=%d, oneshot=%d", type, event, oneshot);
close(fd);
return err;
}

num = ring->index;
if (num != old_idx) {
ulog("mmap: idx: %u, returned: %d.\n", num, err);
while (old_idx != num) {
if (old_idx < KEVENTS_ON_PAGE) {
struct mukevent *m = &ring->event[old_idx];
ulog("%08x: %08x.%08x - %08x\n",
i, m->id.raw[0], m->id.raw[1], m->ret_flags);
} else {
/*
* Mmap next page.
*/
}
if (++old_idx >= KEVENT_MAX_EVENTS)
old_idx = 0;
}
old_idx = num;
}

num = (unsigned)err;
if (num) {
ulog("syscall dump: %u events.\n", num);
uk = (struct ukevent *)buf;
for (i=0; i<num; ++i) {
ulog("%08x: %08x.%08x - %08x.%08x\n",
uk[i].user[0],
uk[i].id.raw[0], uk[i].id.raw[1],
uk[i].ret_data[0], uk[i].ret_data[1]);
}
}
}

close(fd);
return 0;
}