assfail.c revision 35e6f27ad0d19ae8ac48ddcbccbe1af717832f29
/*
* 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 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include "lint.h"
#include "thr_uberdata.h"
const char *panicstr;
ulwp_t *panic_thread;
static mutex_t assert_lock = DEFAULTMUTEX;
static ulwp_t *assert_thread = NULL;
/*
* Called from __assert() to set panicstr and panic_thread.
*/
void
__set_panicstr(const char *msg)
{
panicstr = msg;
panic_thread = __curthread();
}
/*
* Called from exit() (atexit function) to give precedence
* to assertion failures and a core dump over _exit().
*/
void
grab_assert_lock()
{
(void) _lwp_mutex_lock(&assert_lock);
}
static void
Abort(const char *msg)
{
ulwp_t *self;
struct sigaction act;
sigset_t sigmask;
lwpid_t lwpid;
/* to help with core file debugging */
panicstr = msg;
if ((self = __curthread()) != NULL) {
panic_thread = self;
lwpid = self->ul_lwpid;
} else {
lwpid = _lwp_self();
}
/* set SIGABRT signal handler to SIG_DFL w/o grabbing any locks */
(void) memset(&act, 0, sizeof (act));
act.sa_sigaction = SIG_DFL;
(void) __sigaction(SIGABRT, &act, NULL);
/* delete SIGABRT from the signal mask */
(void) sigemptyset(&sigmask);
(void) sigaddset(&sigmask, SIGABRT);
(void) __lwp_sigmask(SIG_UNBLOCK, &sigmask, NULL);
(void) _lwp_kill(lwpid, SIGABRT); /* never returns */
(void) kill(getpid(), SIGABRT); /* if it does, try harder */
_exit(127);
}
/*
* Write a panic message w/o grabbing any locks other than assert_lock.
* We have no idea what locks are held at this point.
*/
static void
common_panic(const char *head, const char *why)
{
char msg[400]; /* no panic() message in the library is this long */
ulwp_t *self;
size_t len1, len2;
if ((self = __curthread()) != NULL)
enter_critical(self);
(void) _lwp_mutex_lock(&assert_lock);
(void) memset(msg, 0, sizeof (msg));
(void) strcpy(msg, head);
len1 = strlen(msg);
len2 = strlen(why);
if (len1 + len2 >= sizeof (msg))
len2 = sizeof (msg) - len1 - 1;
(void) strncat(msg, why, len2);
len1 = strlen(msg);
if (msg[len1 - 1] != '\n')
msg[len1++] = '\n';
(void) __write(2, msg, len1);
Abort(msg);
}
void
thr_panic(const char *why)
{
common_panic("*** libc thread failure: ", why);
}
void
aio_panic(const char *why)
{
common_panic("*** libc aio system failure: ", why);
}
/*
* Utility function for converting a long integer to a string, avoiding stdio.
* 'base' must be one of 10 or 16
*/
void
ultos(uint64_t n, int base, char *s)
{
char lbuf[24]; /* 64 bits fits in 16 hex digits, 20 decimal */
char *cp = lbuf;
do {
*cp++ = "0123456789abcdef"[n%base];
n /= base;
} while (n);
if (base == 16) {
*s++ = '0';
*s++ = 'x';
}
do {
*s++ = *--cp;
} while (cp > lbuf);
*s = '\0';
}
/*
* Report application lock usage error for mutexes and condvars.
* Not called if _THREAD_ERROR_DETECTION=0.
* Continue execution if _THREAD_ERROR_DETECTION=1.
* Dump core if _THREAD_ERROR_DETECTION=2.
*/
void
lock_error(const mutex_t *mp, const char *who, void *cv, const char *msg)
{
mutex_t mcopy;
char buf[800];
uberdata_t *udp;
ulwp_t *self;
lwpid_t lwpid;
pid_t pid;
/*
* Take a snapshot of the mutex before it changes (we hope!).
* Use memcpy() rather than 'mcopy = *mp' in case mp is unaligned.
*/
(void) memcpy(&mcopy, mp, sizeof (mcopy));
/* avoid recursion deadlock */
if ((self = __curthread()) != NULL) {
if (assert_thread == self)
_exit(127);
enter_critical(self);
(void) _lwp_mutex_lock(&assert_lock);
assert_thread = self;
lwpid = self->ul_lwpid;
udp = self->ul_uberdata;
pid = udp->pid;
} else {
self = NULL;
(void) _lwp_mutex_lock(&assert_lock);
lwpid = _lwp_self();
udp = &__uberdata;
pid = getpid();
}
(void) strcpy(buf,
"\n*** _THREAD_ERROR_DETECTION: lock usage error detected ***\n");
(void) strcat(buf, who);
(void) strcat(buf, "(");
if (cv != NULL) {
ultos((uint64_t)(uintptr_t)cv, 16, buf + strlen(buf));
(void) strcat(buf, ", ");
}
ultos((uint64_t)(uintptr_t)mp, 16, buf + strlen(buf));
(void) strcat(buf, ")");
if (msg != NULL) {
(void) strcat(buf, ": ");
(void) strcat(buf, msg);
} else if (!mutex_held(&mcopy)) {
(void) strcat(buf, ": calling thread does not own the lock");
} else if (mcopy.mutex_rcount) {
(void) strcat(buf, ": mutex rcount = ");
ultos((uint64_t)mcopy.mutex_rcount, 10, buf + strlen(buf));
} else {
(void) strcat(buf, ": calling thread already owns the lock");
}
(void) strcat(buf, "\ncalling thread is ");
ultos((uint64_t)(uintptr_t)self, 16, buf + strlen(buf));
(void) strcat(buf, " thread-id ");
ultos((uint64_t)lwpid, 10, buf + strlen(buf));
if (msg != NULL || mutex_held(&mcopy))
/* EMPTY */;
else if (mcopy.mutex_lockw == 0)
(void) strcat(buf, "\nthe lock is unowned");
else if (!(mcopy.mutex_type & USYNC_PROCESS)) {
(void) strcat(buf, "\nthe lock owner is ");
ultos((uint64_t)mcopy.mutex_owner, 16, buf + strlen(buf));
} else {
(void) strcat(buf, " in process ");
ultos((uint64_t)pid, 10, buf + strlen(buf));
(void) strcat(buf, "\nthe lock owner is ");
ultos((uint64_t)mcopy.mutex_owner, 16, buf + strlen(buf));
(void) strcat(buf, " in process ");
ultos((uint64_t)mcopy.mutex_ownerpid, 10, buf + strlen(buf));
}
(void) strcat(buf, "\n\n");
(void) __write(2, buf, strlen(buf));
if (udp->uberflags.uf_thread_error_detection >= 2)
Abort(buf);
assert_thread = NULL;
(void) _lwp_mutex_unlock(&assert_lock);
if (self != NULL)
exit_critical(self);
}
/*
* Report application lock usage error for rwlocks.
* Not called if _THREAD_ERROR_DETECTION=0.
* Continue execution if _THREAD_ERROR_DETECTION=1.
* Dump core if _THREAD_ERROR_DETECTION=2.
*/
void
rwlock_error(const rwlock_t *rp, const char *who, const char *msg)
{
rwlock_t rcopy;
uint32_t rwstate;
char buf[800];
uberdata_t *udp;
ulwp_t *self;
lwpid_t lwpid;
pid_t pid;
int process;
/*
* Take a snapshot of the rwlock before it changes (we hope!).
* Use memcpy() rather than 'rcopy = *rp' in case rp is unaligned.
*/
(void) memcpy(&rcopy, rp, sizeof (rcopy));
/* avoid recursion deadlock */
if ((self = __curthread()) != NULL) {
if (assert_thread == self)
_exit(127);
enter_critical(self);
(void) _lwp_mutex_lock(&assert_lock);
assert_thread = self;
lwpid = self->ul_lwpid;
udp = self->ul_uberdata;
pid = udp->pid;
} else {
self = NULL;
(void) _lwp_mutex_lock(&assert_lock);
lwpid = _lwp_self();
udp = &__uberdata;
pid = getpid();
}
rwstate = (uint32_t)rcopy.rwlock_readers;
process = (rcopy.rwlock_type & USYNC_PROCESS);
(void) strcpy(buf,
"\n*** _THREAD_ERROR_DETECTION: lock usage error detected ***\n");
(void) strcat(buf, who);
(void) strcat(buf, "(");
ultos((uint64_t)(uintptr_t)rp, 16, buf + strlen(buf));
(void) strcat(buf, "): ");
(void) strcat(buf, msg);
(void) strcat(buf, "\ncalling thread is ");
ultos((uint64_t)(uintptr_t)self, 16, buf + strlen(buf));
(void) strcat(buf, " thread-id ");
ultos((uint64_t)lwpid, 10, buf + strlen(buf));
if (process) {
(void) strcat(buf, " in process ");
ultos((uint64_t)pid, 10, buf + strlen(buf));
}
if (rwstate & URW_WRITE_LOCKED) {
(void) strcat(buf, "\nthe writer lock owner is ");
ultos((uint64_t)rcopy.rwlock_owner, 16,
buf + strlen(buf));
if (process) {
(void) strcat(buf, " in process ");
ultos((uint64_t)rcopy.rwlock_ownerpid, 10,
buf + strlen(buf));
}
} else if (rwstate & URW_READERS_MASK) {
(void) strcat(buf, "\nthe reader lock is held by ");
ultos((uint64_t)(rwstate & URW_READERS_MASK), 10,
buf + strlen(buf));
(void) strcat(buf, " readers");
} else {
(void) strcat(buf, "\nthe lock is unowned");
}
if (rwstate & URW_HAS_WAITERS)
(void) strcat(buf, "\nand the lock appears to have waiters");
(void) strcat(buf, "\n\n");
(void) __write(2, buf, strlen(buf));
if (udp->uberflags.uf_thread_error_detection >= 2)
Abort(buf);
assert_thread = NULL;
(void) _lwp_mutex_unlock(&assert_lock);
if (self != NULL)
exit_critical(self);
}
/*
* Report a thread usage error.
* Not called if _THREAD_ERROR_DETECTION=0.
* Writes message and continues execution if _THREAD_ERROR_DETECTION=1.
* Writes message and dumps core if _THREAD_ERROR_DETECTION=2.
*/
void
thread_error(const char *msg)
{
char buf[800];
uberdata_t *udp;
ulwp_t *self;
lwpid_t lwpid;
/* avoid recursion deadlock */
if ((self = __curthread()) != NULL) {
if (assert_thread == self)
_exit(127);
enter_critical(self);
(void) _lwp_mutex_lock(&assert_lock);
assert_thread = self;
lwpid = self->ul_lwpid;
udp = self->ul_uberdata;
} else {
self = NULL;
(void) _lwp_mutex_lock(&assert_lock);
lwpid = _lwp_self();
udp = &__uberdata;
}
(void) strcpy(buf, "\n*** _THREAD_ERROR_DETECTION: "
"thread usage error detected ***\n*** ");
(void) strcat(buf, msg);
(void) strcat(buf, "\n*** calling thread is ");
ultos((uint64_t)(uintptr_t)self, 16, buf + strlen(buf));
(void) strcat(buf, " thread-id ");
ultos((uint64_t)lwpid, 10, buf + strlen(buf));
(void) strcat(buf, "\n\n");
(void) __write(2, buf, strlen(buf));
if (udp->uberflags.uf_thread_error_detection >= 2)
Abort(buf);
assert_thread = NULL;
(void) _lwp_mutex_unlock(&assert_lock);
if (self != NULL)
exit_critical(self);
}
/*
* We use __assfail() because the libc __assert() calls
* gettext() which calls malloc() which grabs a mutex.
* We do everything without calling standard i/o.
* assfail() and _assfail() are exported functions;
* __assfail() is private to libc.
*/
#pragma weak _assfail = __assfail
void
__assfail(const char *assertion, const char *filename, int line_num)
{
char buf[800]; /* no assert() message in the library is this long */
ulwp_t *self;
lwpid_t lwpid;
/* avoid recursion deadlock */
if ((self = __curthread()) != NULL) {
if (assert_thread == self)
_exit(127);
enter_critical(self);
(void) _lwp_mutex_lock(&assert_lock);
assert_thread = self;
lwpid = self->ul_lwpid;
} else {
self = NULL;
(void) _lwp_mutex_lock(&assert_lock);
lwpid = _lwp_self();
}
(void) strcpy(buf, "assertion failed for thread ");
ultos((uint64_t)(uintptr_t)self, 16, buf + strlen(buf));
(void) strcat(buf, ", thread-id ");
ultos((uint64_t)lwpid, 10, buf + strlen(buf));
(void) strcat(buf, ": ");
(void) strcat(buf, assertion);
(void) strcat(buf, ", file ");
(void) strcat(buf, filename);
(void) strcat(buf, ", line ");
ultos((uint64_t)line_num, 10, buf + strlen(buf));
(void) strcat(buf, "\n");
(void) __write(2, buf, strlen(buf));
/*
* We could replace the call to Abort() with the following code
* if we want just to issue a warning message and not die.
* assert_thread = NULL;
* _lwp_mutex_unlock(&assert_lock);
* if (self != NULL)
* exit_critical(self);
*/
Abort(buf);
}
/*
* We define and export this version of assfail() just because libaio
* used to define and export it, needlessly. Now that libaio is folded
* into libc, we need to continue this for ABI/version reasons.
* We don't use "#pragma weak assfail __assfail" in order to avoid
* warnings from the check_fnames utility at build time for libraries
* that define their own version of assfail().
*/
void
assfail(const char *assertion, const char *filename, int line_num)
{
__assfail(assertion, filename, line_num);
}