pools/poold/poold.c

	poold.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * poold - dynamically adjust pool configuration according to load.
 */
#include <errno.h>
#include <jni.h>
#include <libintl.h>
#include <limits.h>
#include <link.h>
#include <locale.h>
#include <poll.h>
#include <pool.h>
#include <priv.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>

#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ucontext.h>
#include "utils.h"

#define POOLD_DEF_CLASSPATH "/usr/lib/pool/JPool.jar"
#define POOLD_DEF_LIBPATH   "/usr/lib/pool"

#if defined(sparc)
#define PLAT    "sparc"
#else
#if defined(i386)
#define PLAT    "i386"
#else
#error Unrecognized platform.
#endif
#endif

#define PID_PROPERTY_NAME   "system.poold.pid"

#define CLASS_FIELD_DESC(class_desc)    "L" class_desc ";"

#define LEVEL_CLASS_DESC    "java/util/logging/Level"
#define POOLD_CLASS_DESC    "com/sun/solaris/domain/pools/Poold"
#define SEVERITY_CLASS_DESC "com/sun/solaris/service/logging/Severity"
#define STRING_CLASS_DESC   "java/lang/String"
#define SYSTEM_CLASS_DESC   "java/lang/System"
#define LOGGER_CLASS_DESC   "java/util/logging/Logger"

extern char *optarg;

static const char *pname;

static enum {
    LD_TERMINAL = 1,
    LD_SYSLOG,
    LD_JAVA
} log_dest = LD_SYSLOG;

typedef enum {
    PGAS_GET_ONLY = 1,
    PGAS_GET_AND_SET
} pgas_mode_t;

static const char PNAME_FMT[] = "%s: ";
static const char ERRNO_FMT[] = ": %s";

static JavaVM *jvm;
static int lflag;

static jmethodID log_mid;
static jobject severity_err;
static jobject severity_notice;
static jobject base_log;
static jclass poold_class;
static jobject poold_instance;
static int instance_running;
static pthread_mutex_t instance_running_lock = PTHREAD_MUTEX_INITIALIZER;

static sigset_t hdl_set;

static void
usage(void)
{
    (void) fprintf(stderr, gettext("Usage:\t%s [-l <level>]\n"), pname);

    exit(E_USAGE);
}

static void
pu_output(int severity, const char *fmt, va_list alist)
{
    int err = errno;
    char line[255] = "";
    jobject jseverity;
    jobject jline;
    JNIEnv *env;
    int detach_required = 0;
    if (pname != NULL && log_dest == LD_TERMINAL)
        (void) snprintf(line, sizeof (line), gettext(PNAME_FMT), pname);

    (void) vsnprintf(line + strlen(line), sizeof (line) - strlen(line),
        fmt, alist);

    if (line[strlen(line) - 1] != '\n')
        (void) snprintf(line + strlen(line), sizeof (line) -
            strlen(line), gettext(ERRNO_FMT), strerror(err));
    else
        line[strlen(line) - 1] = 0;

    switch (log_dest) {
    case LD_TERMINAL:
        (void) fprintf(stderr, "%s\n", line);
        (void) fflush(stderr);
        break;
    case LD_SYSLOG:
        syslog(LOG_ERR, "%s", line);
        break;
    case LD_JAVA:
        if (severity == LOG_ERR)
            jseverity = severity_err;
        else
            jseverity = severity_notice;

        if (jvm) {
            (*jvm)->GetEnv(jvm, (void **)&env, JNI_VERSION_1_2);
            if (env == NULL) {
                detach_required = 1;
                (*jvm)->AttachCurrentThread(jvm,
                    (void **)&env, NULL);
            }
            if ((jline = (*env)->NewStringUTF(env, line)) != NULL)
                (*env)->CallVoidMethod(env, base_log, log_mid,
                    jseverity, jline);
            if (detach_required)
                (*jvm)->DetachCurrentThread(jvm);
        }
    }
}

/*PRINTFLIKE1*/
static void
pu_notice(const char *fmt, ...)
{
    va_list alist;
    va_start(alist, fmt);
    pu_output(LOG_NOTICE, fmt, alist);
    va_end(alist);
}

/*PRINTFLIKE1*/
static void
pu_die(const char *fmt, ...)
{
    va_list alist;
    va_start(alist, fmt);
    pu_output(LOG_ERR, fmt, alist);
    va_end(alist);
    exit(E_ERROR);
}

/*
 * Update the "system.poold.pid" to reflect this instance of poold only
 * if the property hasn't been set already to reflect an existing
 * process, and mode is not set to PGAS_GET_ONLY.  Returns the
 * property's pre-existing value, or -1 otherwise.
 */
static pid_t
poold_get_and_set_pid(pgas_mode_t mode)
{
    pool_conf_t *conf;
    pool_elem_t *pe;
    pool_value_t *val;
    int64_t ival;

    if (!(conf = pool_conf_alloc()))
        return ((pid_t)-1);

    if (pool_conf_open(conf, pool_dynamic_location(), PO_RDWR) != 0) {
        (void) pool_conf_free(conf);
        return ((pid_t)-1);
    }

    pe = pool_conf_to_elem(conf);
    if (!(val = pool_value_alloc())) {
        (void) pool_conf_close(conf);
        return ((pid_t)-1);
    }

    if (pool_get_property(conf, pe, PID_PROPERTY_NAME, val) == POC_INT) {
        if (pool_value_get_int64(val, &ival) != 0) {
            (void) pool_value_free(val);
            (void) pool_conf_close(conf);
            return ((pid_t)-1);
        }
    } else {
        ival = (pid_t)-1;
    }

    if (mode == PGAS_GET_AND_SET) {
        ival = getpid();
        pool_value_set_int64(val, ival);
        (void) pool_put_property(conf, pe, PID_PROPERTY_NAME, val);
        (void) pool_conf_commit(conf, 0);
    }

    (void) pool_value_free(val);
    (void) pool_conf_close(conf);
    pool_conf_free(conf);

    return ((pid_t)ival);
}

/*
 * Reconfigure the JVM by simply updating a dummy property on the
 * system element to force pool_conf_update() to detect a change.
 */
static void
reconfigure()
{
    JNIEnv *env;
    pool_conf_t *conf;
    pool_elem_t *pe;
    pool_value_t *val;
    const char *err_desc;
    int detach_required = 0;

    if ((conf = pool_conf_alloc()) == NULL) {
        err_desc = pool_strerror(pool_error());
        goto destroy;
    }
    if (pool_conf_open(conf, pool_dynamic_location(), PO_RDWR) != 0) {
        err_desc = pool_strerror(pool_error());
        pool_conf_free(conf);
        goto destroy;
    }

    if ((val = pool_value_alloc()) == NULL) {
        err_desc = pool_strerror(pool_error());
        (void) pool_conf_close(conf);
        pool_conf_free(conf);
        goto destroy;
    }
    pe = pool_conf_to_elem(conf);
    pool_value_set_bool(val, 1);
    if (pool_put_property(conf, pe, "system.poold.sighup", val) !=
        PO_SUCCESS) {
        err_desc = pool_strerror(pool_error());
        pool_value_free(val);
        (void) pool_conf_close(conf);
        pool_conf_free(conf);
        goto destroy;
    }
    pool_value_free(val);
    (void) pool_rm_property(conf, pe, "system.poold.sighup");
    if (pool_conf_commit(conf, 0) != PO_SUCCESS) {
        err_desc = pool_strerror(pool_error());
        (void) pool_conf_close(conf);
        pool_conf_free(conf);
        goto destroy;
    }
    (void) pool_conf_close(conf);
    pool_conf_free(conf);
    return;
destroy:
    if (jvm) {
        (*jvm)->GetEnv(jvm, (void **)&env, JNI_VERSION_1_2);
        if (env == NULL) {
            detach_required = 1;
            (*jvm)->AttachCurrentThread(jvm, (void **)&env, NULL);
        }
        if (lflag && (*env)->ExceptionOccurred(env))
            (*env)->ExceptionDescribe(env);
        if (detach_required)
            (*jvm)->DetachCurrentThread(jvm);
        (*jvm)->DestroyJavaVM(jvm);
    }
    pu_die(err_desc);
}

/*
 * If SIGHUP is invoked, we should just re-initialize poold. Since
 * there is no easy way to determine when it's safe to re-initialzie
 * poold, simply update a dummy property on the system element to
 * force pool_conf_update() to detect a change.
 *
 * Both SIGTERM and SIGINT are interpreted as instructions to
 * shutdown.
 */
/*ARGSUSED*/
static void *
handle_sig(void *arg)
{
    for (;;) {
        JNIEnv *env;
        jmethodID poold_shutdown_mid;
        int sig;
        char buf[SIG2STR_MAX];
        int detach_required = 0;

        if ((sig = sigwait(&hdl_set)) < 0)
            pu_die("unexpected error: %d\n", errno);
        (void) sig2str(sig, buf);
        switch (sig) {
        case SIGHUP:
            reconfigure();
            break;
        case SIGINT:
        case SIGTERM:
            (void) pthread_mutex_lock(&instance_running_lock);
            if (instance_running) {
                (void) pthread_mutex_unlock(
                    &instance_running_lock);
                (*jvm)->GetEnv(jvm, (void **)&env,
                    JNI_VERSION_1_2);
                if (env == NULL) {
                    detach_required = 1;
                    (*jvm)->AttachCurrentThread(jvm,
                        (void **)&env, NULL);
                }
                pu_notice("terminating due to signal: SIG%s\n",
                    buf);
                if ((poold_shutdown_mid = (*env)->GetMethodID(
                    env, poold_class, "shutdown", "()V")) !=
                    NULL) {
                    (*env)->CallVoidMethod(env,
                        poold_instance,
                        poold_shutdown_mid);
                } else {
                    (*env)->ExceptionDescribe(env);
                    pu_die("could not invoke"
                        " proper shutdown\n");
                }
                if (detach_required)
                    (*jvm)->DetachCurrentThread(jvm);
            } else {
                (void) pthread_mutex_unlock(
                    &instance_running_lock);
                pu_die("terminated with signal: SIG%s\n", buf);
                /*NOTREACHED*/
            }
            break;
        default:
            pu_die("unexpected signal: SIG%s\n", buf);
        }
    }
    /*NOTREACHED*/
    return (NULL);
}

static const char *
pu_getpname(const char *arg0)
{
    char *p;

    /*
     * Guard against '/' at end of command invocation.
     */
    for (;;) {
        p = strrchr(arg0, '/');
        if (p == NULL) {
            pname = arg0;
            break;
        } else {
            if (*(p + 1) == '\0') {
                *p = '\0';
                continue;
            }

            pname = p + 1;
            break;
        }
    }

    return (pname);
}

int
main(int argc, char *argv[])
{
    char c;
    char log_severity[16] = "";
    pid_t pid;
    JavaVMInitArgs vm_args;
    JavaVMOption vm_opts[5];
    int nopts = 0;
    const char *classpath;
    const char *libpath;
    size_t len;
    const char *err_desc;
    JNIEnv *env;
    jmethodID poold_getinstancewcl_mid;
    jmethodID poold_run_mid;
    jobject log_severity_string = NULL;
    jobject log_severity_obj = NULL;
    jclass severity_class;
    jmethodID severity_cons_mid;
    jfieldID base_log_fid;
    int explain_ex = 1;
    JavaVM *jvm_tmp;
    pthread_t hdl_thread;

    pname = pu_getpname(argv[0]);
    openlog(pname, 0, LOG_DAEMON);
    (void) chdir("/");

    (void) setlocale(LC_ALL, "");
#if !defined(TEXT_DOMAIN)       /* Should be defined with cc -D. */
#define TEXT_DOMAIN "SYS_TEST"  /* Use this only if it wasn't. */
#endif
    (void) textdomain(TEXT_DOMAIN);

    opterr = 0;
    while ((c = getopt(argc, argv, "l:P")) != EOF) {
        switch (c) {
        case 'l':   /* -l option */
            lflag++;
            (void) strlcpy(log_severity, optarg,
                sizeof (log_severity));
            log_dest = LD_TERMINAL;
            break;
        default:
            usage();
            /*NOTREACHED*/
        }
    }

    /*
     * Verify no other poold is running.  This condition is checked
     * again later, but should be checked now since it is more
     * serious (i.e.  should be reported before) than a lack of
     * privileges.
     */
    if (((pid = poold_get_and_set_pid(PGAS_GET_ONLY)) != (pid_t)-1) &&
        pid != getpid() && kill(pid, 0) == 0)
        pu_die(gettext("poold is already active (process %ld)\n"), pid);

    /*
     * Check permission
     */
    if (!priv_ineffect(PRIV_SYS_RES_CONFIG))
        pu_die(gettext(ERR_PRIVILEGE), PRIV_SYS_RES_CONFIG);

    /*
     * Establish the classpath and LD_LIBRARY_PATH for native
     * methods, and get the interpreter going.
     */
    if ((classpath = getenv("POOLD_CLASSPATH")) == NULL) {
        classpath = POOLD_DEF_CLASSPATH;
    } else {
        const char *cur = classpath;

        /*
         * Check the components to make sure they're absolute
         * paths.
         */
        while (cur != NULL && *cur) {
            if (*cur != '/')
                pu_die(gettext(
                    "POOLD_CLASSPATH must contain absolute "
                    "components\n"));
            cur = strchr(cur + 1, ':');
        }
    }
    vm_opts[nopts].optionString = malloc(len = strlen(classpath) +
        strlen("-Djava.class.path=") + 1);
    (void) strlcpy(vm_opts[nopts].optionString, "-Djava.class.path=", len);
    (void) strlcat(vm_opts[nopts++].optionString, classpath, len);

    if ((libpath = getenv("POOLD_LD_LIBRARY_PATH")) == NULL)
        libpath = POOLD_DEF_LIBPATH;
    vm_opts[nopts].optionString = malloc(len = strlen(libpath) +
        strlen("-Djava.library.path=") + 1);
    (void) strlcpy(vm_opts[nopts].optionString, "-Djava.library.path=",
        len);
    (void) strlcat(vm_opts[nopts++].optionString, libpath, len);

    vm_opts[nopts++].optionString = "-Xrs";
    vm_opts[nopts++].optionString = "-enableassertions";

    vm_args.options = vm_opts;
    vm_args.nOptions = nopts;
    vm_args.ignoreUnrecognized = JNI_FALSE;
    vm_args.version = 0x00010002;

    /*
     * XXX - Forking after the VM is created is desirable to
     * guarantee reporting of errors, but cannot be done (see
     * 4919246).
     *
     * If invoked by libpool(3LIB), it's set the system.poold.pid
     * property and forked already.  If invoked directly and -l is
     * specified, forking is not desired.
     */
    if (!lflag && pid != getpid())
        switch (fork()) {
        case 0:
            (void) setsid();
            (void) fclose(stdin);
            (void) fclose(stdout);
            (void) fclose(stderr);
            break;
        case -1:
            pu_die(gettext("cannot fork"));
            /*NOTREACHED*/
        default:
            return (E_PO_SUCCESS);
        }

    /*
     * In order to avoid problems with arbitrary thread selection
     * when handling asynchronous signals, dedicate a thread to
     * look after these signals.
     */
    if (sigemptyset(&hdl_set) < 0 ||
        sigaddset(&hdl_set, SIGHUP) < 0 ||
        sigaddset(&hdl_set, SIGTERM) < 0 ||
        sigaddset(&hdl_set, SIGINT) < 0 ||
        pthread_sigmask(SIG_BLOCK, &hdl_set, NULL) ||
        pthread_create(&hdl_thread, NULL, handle_sig, NULL))
        pu_die(gettext("can't install signal handler"));

    /*
     * Use jvm_tmp when creating the jvm to prevent race
     * conditions with signal handlers. As soon as the call
     * returns, assign the global jvm to jvm_tmp.
     */
    if (JNI_CreateJavaVM(&jvm_tmp, (void **)&env, &vm_args) < 0)
        pu_die(gettext("can't create Java VM"));
    jvm = jvm_tmp;

    /*
     * Locate the Poold class and construct an instance.  A side
     * effect of this is that the poold instance's logHelper will be
     * initialized, establishing loggers for logging errors from
     * this point on.  (Note, in the event of an unanticipated
     * exception, poold will invoke die() itself.)
     */
    err_desc = gettext("JVM-related error initializing poold\n");
    if ((poold_class = (*env)->FindClass(env, POOLD_CLASS_DESC)) == NULL)
        goto destroy;
    if ((poold_getinstancewcl_mid = (*env)->GetStaticMethodID(env,
        poold_class, "getInstanceWithConsoleLogging", "("
        CLASS_FIELD_DESC(SEVERITY_CLASS_DESC) ")"
        CLASS_FIELD_DESC(POOLD_CLASS_DESC))) == NULL)
        goto destroy;
    if ((poold_run_mid = (*env)->GetMethodID(env, poold_class, "run",
        "()V")) == NULL)
        goto destroy;
    if ((severity_class = (*env)->FindClass(env, SEVERITY_CLASS_DESC))
        == NULL)
        goto destroy;
    if ((severity_cons_mid = (*env)->GetStaticMethodID(env, severity_class,
        "getSeverityWithName", "(" CLASS_FIELD_DESC(STRING_CLASS_DESC) ")"
        CLASS_FIELD_DESC(SEVERITY_CLASS_DESC))) == NULL)
        goto destroy;

    /*
     * -l <level> was specified, indicating that messages are to be
     * logged to the console only.
     */
    if (strlen(log_severity) > 0) {
        if ((log_severity_string = (*env)->NewStringUTF(env,
            log_severity)) == NULL)
            goto destroy;
        if ((log_severity_obj = (*env)->CallStaticObjectMethod(env,
            severity_class, severity_cons_mid, log_severity_string)) ==
            NULL) {
            err_desc = gettext("invalid level specified\n");
            explain_ex = 0;
            goto destroy;
        }
    } else
        log_severity_obj = NULL;

    if ((poold_instance = (*env)->CallStaticObjectMethod(env, poold_class,
        poold_getinstancewcl_mid, log_severity_obj)) == NULL)
        goto destroy;

    /*
     * Grab a global reference to poold for use in our signal
     * handlers.
     */
    poold_instance = (*env)->NewGlobalRef(env, poold_instance);

    /*
     * Ready LD_JAVA logging.
     */
    err_desc = gettext("cannot initialize logging\n");
    if ((log_severity_string = (*env)->NewStringUTF(env, "err")) == NULL)
        goto destroy;
    if (!(severity_err = (*env)->CallStaticObjectMethod(env, severity_class,
        severity_cons_mid, log_severity_string)))
        goto destroy;
    if (!(severity_err = (*env)->NewGlobalRef(env, severity_err)))
        goto destroy;

    if ((log_severity_string = (*env)->NewStringUTF(env, "notice")) == NULL)
        goto destroy;
    if (!(severity_notice = (*env)->CallStaticObjectMethod(env,
        severity_class, severity_cons_mid, log_severity_string)))
        goto destroy;
    if (!(severity_notice = (*env)->NewGlobalRef(env, severity_notice)))
        goto destroy;

    if (!(base_log_fid = (*env)->GetStaticFieldID(env, poold_class,
        "BASE_LOG", CLASS_FIELD_DESC(LOGGER_CLASS_DESC))))
        goto destroy;
    if (!(base_log = (*env)->GetStaticObjectField(env, poold_class,
        base_log_fid)))
        goto destroy;
    if (!(base_log = (*env)->NewGlobalRef(env, base_log)))
        goto destroy;
    if (!(log_mid = (*env)->GetMethodID(env, (*env)->GetObjectClass(env,
        base_log), "log", "(" CLASS_FIELD_DESC(LEVEL_CLASS_DESC)
        CLASS_FIELD_DESC(STRING_CLASS_DESC) ")V")))
        goto destroy;
    log_dest = LD_JAVA;

    /*
     * Now we're ready to start poold.  Store our pid in the pools
     * configuration to mark that an instance of poold is active,
     * then invoke Poold.run(), which does not normally return.
     *
     * Note that the ignoreUpdates variable in Poold is used to
     * allow Poold to ignore the pools configuration update that
     * this change triggers. If this code is ever modified to
     * remove or modify this logic, then the Poold class must also
     * be modified to keep the actions synchronized.
     */

    if (((pid = poold_get_and_set_pid(PGAS_GET_AND_SET)) != (pid_t)-1) &&
        pid != getpid() && kill(pid, 0) == 0)
        pu_die(gettext("poold is already active (process %ld)\n"), pid);

    (void) pthread_mutex_lock(&instance_running_lock);
    instance_running = 1;
    (void) pthread_mutex_unlock(&instance_running_lock);
    (*env)->CallVoidMethod(env, poold_instance, poold_run_mid);

    if ((*env)->ExceptionOccurred(env))
        goto destroy;

    (*jvm)->DestroyJavaVM(jvm);
    return (E_PO_SUCCESS);

destroy:
    if (lflag && explain_ex && (*env)->ExceptionOccurred(env))
        (*env)->ExceptionDescribe(env);
    (*jvm)->DestroyJavaVM(jvm);
    pu_die(err_desc);
}