/*
 * NCPTRACE.C
 *
 * cc -I/usr/src/sys ncptrace.c -o /usr/local/bin/ncptrace -lkvm
 *
 * ncptrace
 * ncptrace [path]
 *
 * Trace and dump the kernel namecache hierarchy.  If a path is specified
 * the trace begins there, otherwise the trace begins at the root.
 *
 * $DragonFly: src/test/debug/ncptrace.c,v 1.2 2004/10/06 05:13:20 dillon Exp $
 */

#define _KERNEL_STRUCTURES_
#include <sys/param.h>
#include <sys/user.h>
#include <sys/malloc.h>
#include <sys/signalvar.h>
#include <sys/vnode.h>
#include <sys/namecache.h>

#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_kern.h>
#include <vm/swap_pager.h>
#include <vm/vnode_pager.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <kvm.h>
#include <nlist.h>

struct nlist Nl[] = {
#ifdef CINV_PARENT
    { "_rootncp" },
#else
    { "_rootnamecache" },
#endif
    { NULL }
};

void kkread(kvm_t *kd, u_long addr, void *buf, size_t nbytes);
void dumpncp(kvm_t *kd, int tab, struct namecache *ncptr, const char *path);

main(int ac, char **av)
{
    struct namecache *ncptr;
    kvm_t *kd;
    int i;

    if ((kd = kvm_open(NULL, NULL, NULL, O_RDONLY, "kvm:")) == NULL) {
	perror("kvm_open");
	exit(1);
    }
    if (kvm_nlist(kd, Nl) != 0) {
	perror("kvm_nlist");
	exit(1);
    }
#ifdef CINV_PARENT
    kkread(kd, Nl[0].n_value, &ncptr, sizeof(ncptr));
#else
    ncptr = (void *)Nl[0].n_value;
#endif
    if (ac == 1) {
	dumpncp(kd, 0, ncptr, NULL);
    } else {
	for (i = 1; i < ac; ++i) {
	    if (av[i][0] != '/')
		fprintf(stderr, "%s: path must start at the root\n", av[i]);
	    dumpncp(kd, 0, ncptr, av[i]);
	}
    }
}

void
dumpncp(kvm_t *kd, int tab, struct namecache *ncptr, const char *path)
{
    struct namecache ncp;
    struct namecache *ncscan;
    const char *ptr;
    int haschildren;
    char name[256];

    kkread(kd, (u_long)ncptr, &ncp, sizeof(ncp));
    if (ncp.nc_nlen < sizeof(name)) {
	kkread(kd, (u_long)ncp.nc_name, name, ncp.nc_nlen);
	name[ncp.nc_nlen] = 0;
    } else {
	name[0] = 0;
    }
    if (tab == 0) {
	strcpy(name, "ROOT");
	if (path)
	    ++path;
    } else if (ncp.nc_flag & NCF_MOUNTPT) {
	strcpy(name, "MOUNTGLUE");
    } else if (name[0] == 0) {
	strcpy(name, "?");
	if (path)
	    return;
    } else if (path) {
	if ((ptr = strchr(path, '/')) == NULL)
	    ptr = path + strlen(path);
	if (strlen(name) != ptr - path ||
	    bcmp(name, path, ptr - path) != 0
	) {
	    return;
	}
	path = ptr;
	if (*path == '/')
	    ++path;
	if (*path == 0)
	    path = NULL;
    }

    if (ncp.nc_list.tqh_first)
	haschildren = 1;
    else
	haschildren = 0;

    if (path)
	printf("ELM ");
    else
	printf("%*.*s%s ", tab, tab, "", name);
    printf("[ncp=%p par=%p %04x vp=%p", 
	    ncptr, ncp.nc_parent, ncp.nc_flag, ncp.nc_vp);
    if (ncp.nc_timeout)
	printf(" timo=%d", ncp.nc_timeout);
    if (ncp.nc_refs)
	printf(" refs=%d", ncp.nc_refs);
    if (ncp.nc_exlocks)
	printf(" LOCKED(%d,td=%p)", ncp.nc_exlocks, ncp.nc_locktd);
    printf("]");

    if (path) {
	printf(" %s\n", name);
    } else {
	printf("%s\n", haschildren ? " {" : "");
    }
    for (ncscan = ncp.nc_list.tqh_first; ncscan; ncscan = ncp.nc_entry.tqe_next) {
	kkread(kd, (u_long)ncscan, &ncp, sizeof(ncp));
	dumpncp(kd, (path ? (tab ? tab : 4) : tab + 4), ncscan, path);
    }
    if (haschildren && path == NULL)
	printf("%*.*s}\n", tab, tab, "");
}

void
kkread(kvm_t *kd, u_long addr, void *buf, size_t nbytes)
{
    if (kvm_read(kd, addr, buf, nbytes) != nbytes) {
        perror("kvm_read");
        exit(1);
    }
}