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| Current File : //usr/src/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_diff.c |
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
*/
/*
* zfs diff support
*/
#include <ctype.h>
#include <errno.h>
#include <libintl.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stddef.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <sys/zfs_ioctl.h>
#include <libzfs.h>
#include "libzfs_impl.h"
#define ZDIFF_SNAPDIR "/.zfs/snapshot/"
#define ZDIFF_SHARESDIR "/.zfs/shares/"
#define ZDIFF_PREFIX "zfs-diff-%d"
#define ZDIFF_ADDED '+'
#define ZDIFF_MODIFIED 'M'
#define ZDIFF_REMOVED '-'
#define ZDIFF_RENAMED 'R'
static boolean_t
do_name_cmp(const char *fpath, const char *tpath)
{
char *fname, *tname;
fname = strrchr(fpath, '/') + 1;
tname = strrchr(tpath, '/') + 1;
return (strcmp(fname, tname) == 0);
}
typedef struct differ_info {
zfs_handle_t *zhp;
char *fromsnap;
char *frommnt;
char *tosnap;
char *tomnt;
char *ds;
char *dsmnt;
char *tmpsnap;
char errbuf[1024];
boolean_t isclone;
boolean_t scripted;
boolean_t classify;
boolean_t timestamped;
uint64_t shares;
int zerr;
int cleanupfd;
int outputfd;
int datafd;
} differ_info_t;
/*
* Given a {dsname, object id}, get the object path
*/
static int
get_stats_for_obj(differ_info_t *di, const char *dsname, uint64_t obj,
char *pn, int maxlen, zfs_stat_t *sb)
{
zfs_cmd_t zc = { 0 };
int error;
(void) strlcpy(zc.zc_name, dsname, sizeof (zc.zc_name));
zc.zc_obj = obj;
errno = 0;
error = ioctl(di->zhp->zfs_hdl->libzfs_fd, ZFS_IOC_OBJ_TO_STATS, &zc);
di->zerr = errno;
/* we can get stats even if we failed to get a path */
(void) memcpy(sb, &zc.zc_stat, sizeof (zfs_stat_t));
if (error == 0) {
ASSERT(di->zerr == 0);
(void) strlcpy(pn, zc.zc_value, maxlen);
return (0);
}
if (di->zerr == EPERM) {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"The sys_config privilege or diff delegated permission "
"is needed\nto discover path names"));
return (-1);
} else {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"Unable to determine path or stats for "
"object %lld in %s"), obj, dsname);
return (-1);
}
}
/*
* stream_bytes
*
* Prints a file name out a character at a time. If the character is
* not in the range of what we consider "printable" ASCII, display it
* as an escaped 3-digit octal value. ASCII values less than a space
* are all control characters and we declare the upper end as the
* DELete character. This also is the last 7-bit ASCII character.
* We choose to treat all 8-bit ASCII as not printable for this
* application.
*/
static void
stream_bytes(FILE *fp, const char *string)
{
while (*string) {
if (*string > ' ' && *string != '\\' && *string < '\177')
(void) fprintf(fp, "%c", *string++);
else {
(void) fprintf(fp, "\\%03hho",
(unsigned char)*string++);
}
}
}
static void
print_what(FILE *fp, mode_t what)
{
char symbol;
switch (what & S_IFMT) {
case S_IFBLK:
symbol = 'B';
break;
case S_IFCHR:
symbol = 'C';
break;
case S_IFDIR:
symbol = '/';
break;
#ifdef S_IFDOOR
case S_IFDOOR:
symbol = '>';
break;
#endif
case S_IFIFO:
symbol = '|';
break;
case S_IFLNK:
symbol = '@';
break;
#ifdef S_IFPORT
case S_IFPORT:
symbol = 'P';
break;
#endif
case S_IFSOCK:
symbol = '=';
break;
case S_IFREG:
symbol = 'F';
break;
default:
symbol = '?';
break;
}
(void) fprintf(fp, "%c", symbol);
}
static void
print_cmn(FILE *fp, differ_info_t *di, const char *file)
{
stream_bytes(fp, di->dsmnt);
stream_bytes(fp, file);
}
static void
print_rename(FILE *fp, differ_info_t *di, const char *old, const char *new,
zfs_stat_t *isb)
{
if (di->timestamped)
(void) fprintf(fp, "%10lld.%09lld\t",
(longlong_t)isb->zs_ctime[0],
(longlong_t)isb->zs_ctime[1]);
(void) fprintf(fp, "%c\t", ZDIFF_RENAMED);
if (di->classify) {
print_what(fp, isb->zs_mode);
(void) fprintf(fp, "\t");
}
print_cmn(fp, di, old);
if (di->scripted)
(void) fprintf(fp, "\t");
else
(void) fprintf(fp, " -> ");
print_cmn(fp, di, new);
(void) fprintf(fp, "\n");
}
static void
print_link_change(FILE *fp, differ_info_t *di, int delta, const char *file,
zfs_stat_t *isb)
{
if (di->timestamped)
(void) fprintf(fp, "%10lld.%09lld\t",
(longlong_t)isb->zs_ctime[0],
(longlong_t)isb->zs_ctime[1]);
(void) fprintf(fp, "%c\t", ZDIFF_MODIFIED);
if (di->classify) {
print_what(fp, isb->zs_mode);
(void) fprintf(fp, "\t");
}
print_cmn(fp, di, file);
(void) fprintf(fp, "\t(%+d)", delta);
(void) fprintf(fp, "\n");
}
static void
print_file(FILE *fp, differ_info_t *di, char type, const char *file,
zfs_stat_t *isb)
{
if (di->timestamped)
(void) fprintf(fp, "%10lld.%09lld\t",
(longlong_t)isb->zs_ctime[0],
(longlong_t)isb->zs_ctime[1]);
(void) fprintf(fp, "%c\t", type);
if (di->classify) {
print_what(fp, isb->zs_mode);
(void) fprintf(fp, "\t");
}
print_cmn(fp, di, file);
(void) fprintf(fp, "\n");
}
static int
write_inuse_diffs_one(FILE *fp, differ_info_t *di, uint64_t dobj)
{
struct zfs_stat fsb, tsb;
boolean_t same_name;
mode_t fmode, tmode;
char fobjname[MAXPATHLEN], tobjname[MAXPATHLEN];
int fobjerr, tobjerr;
int change;
if (dobj == di->shares)
return (0);
/*
* Check the from and to snapshots for info on the object. If
* we get ENOENT, then the object just didn't exist in that
* snapshot. If we get ENOTSUP, then we tried to get
* info on a non-ZPL object, which we don't care about anyway.
*/
fobjerr = get_stats_for_obj(di, di->fromsnap, dobj, fobjname,
MAXPATHLEN, &fsb);
if (fobjerr && di->zerr != ENOENT && di->zerr != ENOTSUP)
return (-1);
tobjerr = get_stats_for_obj(di, di->tosnap, dobj, tobjname,
MAXPATHLEN, &tsb);
if (tobjerr && di->zerr != ENOENT && di->zerr != ENOTSUP)
return (-1);
/*
* Unallocated object sharing the same meta dnode block
*/
if (fobjerr && tobjerr) {
ASSERT(di->zerr == ENOENT || di->zerr == ENOTSUP);
di->zerr = 0;
return (0);
}
di->zerr = 0; /* negate get_stats_for_obj() from side that failed */
fmode = fsb.zs_mode & S_IFMT;
tmode = tsb.zs_mode & S_IFMT;
if (fmode == S_IFDIR || tmode == S_IFDIR || fsb.zs_links == 0 ||
tsb.zs_links == 0)
change = 0;
else
change = tsb.zs_links - fsb.zs_links;
if (fobjerr) {
if (change) {
print_link_change(fp, di, change, tobjname, &tsb);
return (0);
}
print_file(fp, di, ZDIFF_ADDED, tobjname, &tsb);
return (0);
} else if (tobjerr) {
if (change) {
print_link_change(fp, di, change, fobjname, &fsb);
return (0);
}
print_file(fp, di, ZDIFF_REMOVED, fobjname, &fsb);
return (0);
}
if (fmode != tmode && fsb.zs_gen == tsb.zs_gen)
tsb.zs_gen++; /* Force a generational difference */
same_name = do_name_cmp(fobjname, tobjname);
/* Simple modification or no change */
if (fsb.zs_gen == tsb.zs_gen) {
/* No apparent changes. Could we assert !this? */
if (fsb.zs_ctime[0] == tsb.zs_ctime[0] &&
fsb.zs_ctime[1] == tsb.zs_ctime[1])
return (0);
if (change) {
print_link_change(fp, di, change,
change > 0 ? fobjname : tobjname, &tsb);
} else if (same_name) {
print_file(fp, di, ZDIFF_MODIFIED, fobjname, &tsb);
} else {
print_rename(fp, di, fobjname, tobjname, &tsb);
}
return (0);
} else {
/* file re-created or object re-used */
print_file(fp, di, ZDIFF_REMOVED, fobjname, &fsb);
print_file(fp, di, ZDIFF_ADDED, tobjname, &tsb);
return (0);
}
}
static int
write_inuse_diffs(FILE *fp, differ_info_t *di, dmu_diff_record_t *dr)
{
uint64_t o;
int err;
for (o = dr->ddr_first; o <= dr->ddr_last; o++) {
if (err = write_inuse_diffs_one(fp, di, o))
return (err);
}
return (0);
}
static int
describe_free(FILE *fp, differ_info_t *di, uint64_t object, char *namebuf,
int maxlen)
{
struct zfs_stat sb;
if (get_stats_for_obj(di, di->fromsnap, object, namebuf,
maxlen, &sb) != 0) {
/* Let it slide, if in the delete queue on from side */
if (di->zerr == ENOENT && sb.zs_links == 0) {
di->zerr = 0;
return (0);
}
return (-1);
}
print_file(fp, di, ZDIFF_REMOVED, namebuf, &sb);
return (0);
}
static int
write_free_diffs(FILE *fp, differ_info_t *di, dmu_diff_record_t *dr)
{
zfs_cmd_t zc = { 0 };
libzfs_handle_t *lhdl = di->zhp->zfs_hdl;
char fobjname[MAXPATHLEN];
(void) strlcpy(zc.zc_name, di->fromsnap, sizeof (zc.zc_name));
zc.zc_obj = dr->ddr_first - 1;
ASSERT(di->zerr == 0);
while (zc.zc_obj < dr->ddr_last) {
int err;
err = ioctl(lhdl->libzfs_fd, ZFS_IOC_NEXT_OBJ, &zc);
if (err == 0) {
if (zc.zc_obj == di->shares) {
zc.zc_obj++;
continue;
}
if (zc.zc_obj > dr->ddr_last) {
break;
}
err = describe_free(fp, di, zc.zc_obj, fobjname,
MAXPATHLEN);
if (err)
break;
} else if (errno == ESRCH) {
break;
} else {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"next allocated object (> %lld) find failure"),
zc.zc_obj);
di->zerr = errno;
break;
}
}
if (di->zerr)
return (-1);
return (0);
}
static void *
differ(void *arg)
{
differ_info_t *di = arg;
dmu_diff_record_t dr;
FILE *ofp;
int err = 0;
if ((ofp = fdopen(di->outputfd, "w")) == NULL) {
di->zerr = errno;
(void) strerror_r(errno, di->errbuf, sizeof (di->errbuf));
(void) close(di->datafd);
return ((void *)-1);
}
for (;;) {
char *cp = (char *)&dr;
int len = sizeof (dr);
int rv;
do {
rv = read(di->datafd, cp, len);
cp += rv;
len -= rv;
} while (len > 0 && rv > 0);
if (rv < 0 || (rv == 0 && len != sizeof (dr))) {
di->zerr = EPIPE;
break;
} else if (rv == 0) {
/* end of file at a natural breaking point */
break;
}
switch (dr.ddr_type) {
case DDR_FREE:
err = write_free_diffs(ofp, di, &dr);
break;
case DDR_INUSE:
err = write_inuse_diffs(ofp, di, &dr);
break;
default:
di->zerr = EPIPE;
break;
}
if (err || di->zerr)
break;
}
(void) fclose(ofp);
(void) close(di->datafd);
if (err)
return ((void *)-1);
if (di->zerr) {
ASSERT(di->zerr == EINVAL);
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"Internal error: bad data from diff IOCTL"));
return ((void *)-1);
}
return ((void *)0);
}
static int
find_shares_object(differ_info_t *di)
{
char fullpath[MAXPATHLEN];
struct stat64 sb = { 0 };
(void) strlcpy(fullpath, di->dsmnt, MAXPATHLEN);
(void) strlcat(fullpath, ZDIFF_SHARESDIR, MAXPATHLEN);
if (stat64(fullpath, &sb) != 0) {
#ifdef sun
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN, "Cannot stat %s"), fullpath);
return (zfs_error(di->zhp->zfs_hdl, EZFS_DIFF, di->errbuf));
#else
return (0);
#endif
}
di->shares = (uint64_t)sb.st_ino;
return (0);
}
static int
make_temp_snapshot(differ_info_t *di)
{
libzfs_handle_t *hdl = di->zhp->zfs_hdl;
zfs_cmd_t zc = { 0 };
(void) snprintf(zc.zc_value, sizeof (zc.zc_value),
ZDIFF_PREFIX, getpid());
(void) strlcpy(zc.zc_name, di->ds, sizeof (zc.zc_name));
zc.zc_cleanup_fd = di->cleanupfd;
if (ioctl(hdl->libzfs_fd, ZFS_IOC_TMP_SNAPSHOT, &zc) != 0) {
int err = errno;
if (err == EPERM) {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN, "The diff delegated "
"permission is needed in order\nto create a "
"just-in-time snapshot for diffing\n"));
return (zfs_error(hdl, EZFS_DIFF, di->errbuf));
} else {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN, "Cannot create just-in-time "
"snapshot of '%s'"), zc.zc_name);
return (zfs_standard_error(hdl, err, di->errbuf));
}
}
di->tmpsnap = zfs_strdup(hdl, zc.zc_value);
di->tosnap = zfs_asprintf(hdl, "%s@%s", di->ds, di->tmpsnap);
return (0);
}
static void
teardown_differ_info(differ_info_t *di)
{
free(di->ds);
free(di->dsmnt);
free(di->fromsnap);
free(di->frommnt);
free(di->tosnap);
free(di->tmpsnap);
free(di->tomnt);
(void) close(di->cleanupfd);
}
static int
get_snapshot_names(differ_info_t *di, const char *fromsnap,
const char *tosnap)
{
libzfs_handle_t *hdl = di->zhp->zfs_hdl;
char *atptrf = NULL;
char *atptrt = NULL;
int fdslen, fsnlen;
int tdslen, tsnlen;
/*
* Can accept
* dataset@snap1
* dataset@snap1 dataset@snap2
* dataset@snap1 @snap2
* dataset@snap1 dataset
* @snap1 dataset@snap2
*/
if (tosnap == NULL) {
/* only a from snapshot given, must be valid */
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"Badly formed snapshot name %s"), fromsnap);
if (!zfs_validate_name(hdl, fromsnap, ZFS_TYPE_SNAPSHOT,
B_FALSE)) {
return (zfs_error(hdl, EZFS_INVALIDNAME,
di->errbuf));
}
atptrf = strchr(fromsnap, '@');
ASSERT(atptrf != NULL);
fdslen = atptrf - fromsnap;
di->fromsnap = zfs_strdup(hdl, fromsnap);
di->ds = zfs_strdup(hdl, fromsnap);
di->ds[fdslen] = '\0';
/* the to snap will be a just-in-time snap of the head */
return (make_temp_snapshot(di));
}
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"Unable to determine which snapshots to compare"));
atptrf = strchr(fromsnap, '@');
atptrt = strchr(tosnap, '@');
fdslen = atptrf ? atptrf - fromsnap : strlen(fromsnap);
tdslen = atptrt ? atptrt - tosnap : strlen(tosnap);
fsnlen = strlen(fromsnap) - fdslen; /* includes @ sign */
tsnlen = strlen(tosnap) - tdslen; /* includes @ sign */
if (fsnlen <= 1 || tsnlen == 1 || (fdslen == 0 && tdslen == 0) ||
(fsnlen == 0 && tsnlen == 0)) {
return (zfs_error(hdl, EZFS_INVALIDNAME, di->errbuf));
} else if ((fdslen > 0 && tdslen > 0) &&
((tdslen != fdslen || strncmp(fromsnap, tosnap, fdslen) != 0))) {
/*
* not the same dataset name, might be okay if
* tosnap is a clone of a fromsnap descendant.
*/
char origin[ZFS_MAXNAMELEN];
zprop_source_t src;
zfs_handle_t *zhp;
di->ds = zfs_alloc(di->zhp->zfs_hdl, tdslen + 1);
(void) strncpy(di->ds, tosnap, tdslen);
di->ds[tdslen] = '\0';
zhp = zfs_open(hdl, di->ds, ZFS_TYPE_FILESYSTEM);
while (zhp != NULL) {
(void) zfs_prop_get(zhp, ZFS_PROP_ORIGIN,
origin, sizeof (origin), &src, NULL, 0, B_FALSE);
if (strncmp(origin, fromsnap, fsnlen) == 0)
break;
(void) zfs_close(zhp);
zhp = zfs_open(hdl, origin, ZFS_TYPE_FILESYSTEM);
}
if (zhp == NULL) {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"Not an earlier snapshot from the same fs"));
return (zfs_error(hdl, EZFS_INVALIDNAME, di->errbuf));
} else {
(void) zfs_close(zhp);
}
di->isclone = B_TRUE;
di->fromsnap = zfs_strdup(hdl, fromsnap);
if (tsnlen) {
di->tosnap = zfs_strdup(hdl, tosnap);
} else {
return (make_temp_snapshot(di));
}
} else {
int dslen = fdslen ? fdslen : tdslen;
di->ds = zfs_alloc(hdl, dslen + 1);
(void) strncpy(di->ds, fdslen ? fromsnap : tosnap, dslen);
di->ds[dslen] = '\0';
di->fromsnap = zfs_asprintf(hdl, "%s%s", di->ds, atptrf);
if (tsnlen) {
di->tosnap = zfs_asprintf(hdl, "%s%s", di->ds, atptrt);
} else {
return (make_temp_snapshot(di));
}
}
return (0);
}
static int
get_mountpoint(differ_info_t *di, char *dsnm, char **mntpt)
{
boolean_t mounted;
mounted = is_mounted(di->zhp->zfs_hdl, dsnm, mntpt);
if (mounted == B_FALSE) {
(void) snprintf(di->errbuf, sizeof (di->errbuf),
dgettext(TEXT_DOMAIN,
"Cannot diff an unmounted snapshot"));
return (zfs_error(di->zhp->zfs_hdl, EZFS_BADTYPE, di->errbuf));
}
/* Avoid a double slash at the beginning of root-mounted datasets */
if (**mntpt == '/' && *(*mntpt + 1) == '\0')
**mntpt = '\0';
return (0);
}
static int
get_mountpoints(differ_info_t *di)
{
char *strptr;
char *frommntpt;
/*
* first get the mountpoint for the parent dataset
*/
if (get_mountpoint(di, di->ds, &di->dsmnt) != 0)
return (-1);
strptr = strchr(di->tosnap, '@');
ASSERT3P(strptr, !=, NULL);
di->tomnt = zfs_asprintf(di->zhp->zfs_hdl, "%s%s%s", di->dsmnt,
ZDIFF_SNAPDIR, ++strptr);
strptr = strchr(di->fromsnap, '@');
ASSERT3P(strptr, !=, NULL);
frommntpt = di->dsmnt;
if (di->isclone) {
char *mntpt;
int err;
*strptr = '\0';
err = get_mountpoint(di, di->fromsnap, &mntpt);
*strptr = '@';
if (err != 0)
return (-1);
frommntpt = mntpt;
}
di->frommnt = zfs_asprintf(di->zhp->zfs_hdl, "%s%s%s", frommntpt,
ZDIFF_SNAPDIR, ++strptr);
if (di->isclone)
free(frommntpt);
return (0);
}
static int
setup_differ_info(zfs_handle_t *zhp, const char *fromsnap,
const char *tosnap, differ_info_t *di)
{
di->zhp = zhp;
di->cleanupfd = open(ZFS_DEV, O_RDWR|O_EXCL);
VERIFY(di->cleanupfd >= 0);
if (get_snapshot_names(di, fromsnap, tosnap) != 0)
return (-1);
if (get_mountpoints(di) != 0)
return (-1);
if (find_shares_object(di) != 0)
return (-1);
return (0);
}
int
zfs_show_diffs(zfs_handle_t *zhp, int outfd, const char *fromsnap,
const char *tosnap, int flags)
{
zfs_cmd_t zc = { 0 };
char errbuf[1024];
differ_info_t di = { 0 };
pthread_t tid;
int pipefd[2];
int iocerr;
(void) snprintf(errbuf, sizeof (errbuf),
dgettext(TEXT_DOMAIN, "zfs diff failed"));
if (setup_differ_info(zhp, fromsnap, tosnap, &di)) {
teardown_differ_info(&di);
return (-1);
}
if (pipe(pipefd)) {
zfs_error_aux(zhp->zfs_hdl, strerror(errno));
teardown_differ_info(&di);
return (zfs_error(zhp->zfs_hdl, EZFS_PIPEFAILED, errbuf));
}
di.scripted = (flags & ZFS_DIFF_PARSEABLE);
di.classify = (flags & ZFS_DIFF_CLASSIFY);
di.timestamped = (flags & ZFS_DIFF_TIMESTAMP);
di.outputfd = outfd;
di.datafd = pipefd[0];
if (pthread_create(&tid, NULL, differ, &di)) {
zfs_error_aux(zhp->zfs_hdl, strerror(errno));
(void) close(pipefd[0]);
(void) close(pipefd[1]);
teardown_differ_info(&di);
return (zfs_error(zhp->zfs_hdl,
EZFS_THREADCREATEFAILED, errbuf));
}
/* do the ioctl() */
(void) strlcpy(zc.zc_value, di.fromsnap, strlen(di.fromsnap) + 1);
(void) strlcpy(zc.zc_name, di.tosnap, strlen(di.tosnap) + 1);
zc.zc_cookie = pipefd[1];
iocerr = ioctl(zhp->zfs_hdl->libzfs_fd, ZFS_IOC_DIFF, &zc);
if (iocerr != 0) {
(void) snprintf(errbuf, sizeof (errbuf),
dgettext(TEXT_DOMAIN, "Unable to obtain diffs"));
if (errno == EPERM) {
zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
"\n The sys_mount privilege or diff delegated "
"permission is needed\n to execute the "
"diff ioctl"));
} else if (errno == EXDEV) {
zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
"\n Not an earlier snapshot from the same fs"));
} else if (errno != EPIPE || di.zerr == 0) {
zfs_error_aux(zhp->zfs_hdl, strerror(errno));
}
(void) close(pipefd[1]);
(void) pthread_cancel(tid);
(void) pthread_join(tid, NULL);
teardown_differ_info(&di);
if (di.zerr != 0 && di.zerr != EPIPE) {
zfs_error_aux(zhp->zfs_hdl, strerror(di.zerr));
return (zfs_error(zhp->zfs_hdl, EZFS_DIFF, di.errbuf));
} else {
return (zfs_error(zhp->zfs_hdl, EZFS_DIFFDATA, errbuf));
}
}
(void) close(pipefd[1]);
(void) pthread_join(tid, NULL);
if (di.zerr != 0) {
zfs_error_aux(zhp->zfs_hdl, strerror(di.zerr));
return (zfs_error(zhp->zfs_hdl, EZFS_DIFF, di.errbuf));
}
teardown_differ_info(&di);
return (0);
}