/*
* 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 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
#include <stdio.h>
#include <limits.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <pkglocs.h>
#include <locale.h>
#include <libintl.h>
#include <string.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/signal.h>
#include <sys/fault.h>
#include <sys/syscall.h>
#include <pkglib.h>
#include "libadm.h"
extern int errno;
#define ST_QUIT 1
#define ST_OK 0
#define LOCKFILE ".lockfile"
#define LCKBUFSIZ 128
#define LOCKWAIT 20 /* seconds between retries */
#define LOCKRETRY 10 /* number of retries for a DB lock */
#define LF_SIZE 128 /* size of governing lock file */
#define MSG_WTING "NOTE: Waiting for access to the package database."
#define MSG_XWTING "NOTE: Waiting for exclusive access to the package " \
"database."
#define MSG_WTFOR "NOTE: Waiting for %s of %s to complete."
#define WRN_CLRLOCK "WARNING: Stale lock installed for %s, pkg %s quit " \
"in %s state."
#define WRN_CLRLOCK1 "Removing lock."
#define ERR_MKLOCK "unable to create governing lock file <%s>."
#define ERR_NOLOCK "unable to install governing lock on <%s>."
#define ERR_NOOPEN "unable to open <%s>."
#define ERR_LCKTBL "unable to lock <%s> - lock table full."
#define ERR_LCKREM "unable to lock <%s> - remote host unavailable."
#define ERR_BADLCK "unable to lock <%s> - unknown error."
#define ERR_DEADLCK "unable to lock <%s> - deadlock condition."
static pid_t lock_pid;
static int lock_fd, lock_is_applied;
static char lock_name[PKGSIZ];
static char lock_pkg[PKGSIZ];
static char lock_place[PKGSIZ];
static unsigned int lock_state;
static char lockbuf[LCKBUFSIZ];
static char lockpath[PATH_MAX];
#define LOCK_NAME_OLD_PKG "old version pkg command"
#define LOCK_PKG_UNKNOWN "unknown package"
#define LOCK_PLACE_UNKNOWN "unknown"
/*
* This function writes the PID, effective utility name, package name,
* current progress of the utility and the exit state to the lockfile in
* support of post mortem operations.
*/
static int
wrlockdata(int fd, int this_pid, char *this_name,
char *this_pkg, char *this_place, unsigned int this_state)
{
if (this_pid < 0 || *this_name == '\000')
return (0);
(void) memset(lockbuf, 0, LCKBUFSIZ);
(void) snprintf(lockbuf, sizeof (lockbuf),
"%d %s %s %s %d\n", this_pid, this_name, this_pkg,
this_place, this_state);
(void) lseek(fd, 0, SEEK_SET);
if (write(fd, lockbuf, LF_SIZE) == LF_SIZE)
return (1);
else
return (0);
}
/*
* This function reads the lockfile to obtain the PID and name of the lock
* holder. Upon those rare circumstances that an older version of pkgadd
* created the lock, this detects that zero-length file and provides the
* appropriate data. Since this data is only used if an actual lock (from
* lockf()) is detected, a manually created .lockfile will not result in a
* message.
*/
static void
rdlockdata(int fd)
{
(void) lseek(fd, 0, SEEK_SET);
if (read(fd, lockbuf, LF_SIZE) != LF_SIZE) {
lock_pid = 0;
(void) strlcpy(lock_name, LOCK_NAME_OLD_PKG,
sizeof (lock_name));
(void) strlcpy(lock_pkg, LOCK_PKG_UNKNOWN,
sizeof (lock_pkg));
(void) strlcpy(lock_place, LOCK_PLACE_UNKNOWN,
sizeof (lock_place));
lock_state = ST_OK;
} else {
/* LINTED format argument contains unbounded string specifier */
(void) sscanf(lockbuf, "%ld %s %s %s %u", &lock_pid,
lock_name, lock_pkg, lock_place, &lock_state);
}
}
static void
do_alarm(int n)
{
#ifdef lint
int i = n;
n = i;
#endif /* lint */
(void) signal(SIGALRM, do_alarm);
(void) alarm(LOCKWAIT);
}
/*
* This establishes a locked status file for a pkgadd, pkgrm or swmtool - any
* of the complex package processes. Since numerous packages currently use
* installf and removef in preinstall scripts, we can't enforce a contents
* file write lock throughout the install process. In 2.7 we will enforce the
* write lock and allow this lock to serve as a simple information carrier
* which can be used by installf and removef too.
* Arguments:
* util_name - the name of the utility that is claiming the lock
* pkg_name - the package that is being locked (or "all package")
* place - a string of ascii characters that defines the initial "place" where
* the current operation is - this is updated by lockupd() and is a string
* is used fr post mortem operations if the utility should quit improperly.
* Returns (int):
* == 0 - failure
* != 0 - success
*/
int
lockinst(char *util_name, char *pkg_name, char *place)
{
int fd, retry_cnt;
/* assume "initial" if no "place" during processing specified */
if ((place == (char *)NULL) || (*place == '\0')) {
place = "initial";
}
(void) snprintf(lockpath, sizeof (lockpath),
"%s/%s", get_PKGADM(), LOCKFILE);
/* If the exit file is not present, create it. */
/* LINTED O_CREAT without O_EXCL specified in call to open() */
if ((fd = open(lockpath, O_RDWR | O_CREAT, 0600)) == -1) {
progerr(gettext(ERR_MKLOCK), lockpath);
return (0);
}
lock_fd = fd;
retry_cnt = LOCKRETRY;
lock_is_applied = 0;
(void) signal(SIGALRM, do_alarm);
(void) alarm(LOCKWAIT);
/*
* This tries to create the lock LOCKRETRY times waiting LOCKWAIT
* seconds between retries.
*/
do {
if (lockf(fd, F_LOCK, 0)) {
/*
* Try to read the status of the last (or current)
* utility.
*/
rdlockdata(fd);
logerr(gettext(MSG_WTFOR), lock_name, lock_pkg);
} else { /* This process has the lock. */
rdlockdata(fd);
if (lock_state != 0) {
logerr(gettext(WRN_CLRLOCK), lock_name,
lock_pkg, lock_place);
logerr(gettext(WRN_CLRLOCK1));
}
lock_pid = getpid();
(void) strlcpy(lock_name, (util_name) ?
util_name : gettext("unknown"), sizeof (lock_name));
(void) strlcpy(lock_pkg, (pkg_name) ?
pkg_name : gettext("unknown"), sizeof (lock_pkg));
(void) wrlockdata(fd, lock_pid, lock_name,
lock_pkg, place, ST_QUIT);
lock_is_applied = 1;
break;
}
} while (retry_cnt--);
(void) signal(SIGALRM, SIG_IGN);
if (!lock_is_applied) {
progerr(gettext(ERR_NOLOCK), lockpath);
return (0);
}
return (1);
}
/*
* This function updates the utility progress data in the lock file. It is
* used for post mortem operations if the utility should quit improperly.
*/
void
lockupd(char *place)
{
(void) wrlockdata(lock_fd, lock_pid, lock_name, lock_pkg, place,
ST_QUIT);
}
/*
* This clears the governing lock and closes the lock file. If this was
* called already, it just returns.
*/
void
unlockinst(void)
{
if (lock_is_applied) {
(void) wrlockdata(lock_fd, lock_pid, lock_name, lock_pkg,
"finished", ST_OK);
/*
* If close() fails, we can't be sure the lock has been
* removed, so we assume the worst in case this function is
* called again.
*/
if (close(lock_fd) != -1)
lock_is_applied = 0;
}
}