transport.c

来自「This is a resource based on j2me embedde」· C语言 代码 · 共 641 行 · 第 1/2 页

/*
 * @(#)transport.c	1.35 06/10/25
 *
 * Copyright  1990-2008 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 only, as published by the Free Software Foundation. 
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt). 
 * 
 * You should have received a copy of the GNU General Public License
 * version 2 along with this work; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA 
 * 
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions. 
 */

#include "util.h"
#include "transport.h"
#include "debugLoop.h"
#include "sys.h"

static jdwpTransportEnv *transport;
static jrawMonitorID listenerLock;
static jrawMonitorID sendLock;

/*                  
 * data structure used for passing transport info from thread to thread
 */
typedef struct TransportInfo {
    char *name;
    jdwpTransportEnv *transport;
    char *address;
    long timeout;
} TransportInfo;

static struct jdwpTransportCallback callback = {jvmtiAllocate, jvmtiDeallocate};

/*
 * Print the last transport error
 */
static void 
printLastError(jdwpTransportEnv *t, jdwpTransportError err)
{
    char  *msg;
    jbyte *utf8msg;
    jdwpTransportError rv;
    
    msg     = NULL;
    utf8msg = NULL;
    rv = (*t)->GetLastError(t, &msg); /* This is a platform encoded string */
    if ( msg != NULL ) {
        int len;
        int maxlen;

        /* Convert this string to UTF8 */
        len = (int)strlen(msg);
        maxlen = len+len/2+2; /* Should allow for plenty of room */
        utf8msg = (jbyte*)jvmtiAllocate(maxlen+1);
        (void)(gdata->npt->utf8FromPlatform)(gdata->npt->utf,
            msg, len, utf8msg, maxlen);
        utf8msg[maxlen] = 0;
    }
    if (rv == JDWPTRANSPORT_ERROR_NONE) {
        ERROR_MESSAGE(("transport error %d: %s",err, utf8msg));
    } else if ( msg!=NULL ) {
        ERROR_MESSAGE(("transport error %d: %s",err, utf8msg));
    } else {
        ERROR_MESSAGE(("transport error %d: %s",err, "UNKNOWN"));
    }
    jvmtiDeallocate(msg);
    jvmtiDeallocate(utf8msg);
}

/* Find OnLoad symbol */
static jdwpTransport_OnLoad_t
findTransportOnLoad(void *handle)
{
    jdwpTransport_OnLoad_t onLoad;

    onLoad = (jdwpTransport_OnLoad_t)NULL;
    if (handle == NULL) {
        return onLoad;
    }
    onLoad = (jdwpTransport_OnLoad_t)
                 dbgsysFindLibraryEntry(handle, "jdwpTransport_OnLoad");
    return onLoad;
}

/* Load transport library (directory=="" means do system search) */
static void *
loadTransportLibrary(char *libdir, char *name)
{
    void *handle;
    char libname[MAXPATHLEN+2];
    char buf[MAXPATHLEN*2+100];
    char *plibdir;
   
    /* Convert libdir from UTF-8 to platform encoding */
    plibdir = NULL;
    if ( libdir != NULL ) {
        int  len;
        
        len = (int)strlen(libdir);
        (void)(gdata->npt->utf8ToPlatform)(gdata->npt->utf,
            (jbyte*)libdir, len, buf, (int)sizeof(buf));
        plibdir = buf;
    }
    
    /* Construct library name (simple name or full path) */
    dbgsysBuildLibName(libname, sizeof(libname), plibdir, name);
    
    /* dlopen (unix) / LoadLibrary (windows) the transport library */
    handle = dbgsysLoadLibrary(libname);
    return handle;
}

/*
 * loadTransport() is adapted from loadJVMHelperLib() in 
 * JDK 1.2 javai.c v1.61
 */
static jdwpError
loadTransport(char *name, jdwpTransportEnv **transportPtr)
{
    JNIEnv                 *env;
    jdwpTransport_OnLoad_t  onLoad;
    void                   *handle;
    char                   *libdir;

    /* Make sure library name is not empty */
    if (name == NULL) {
        ERROR_MESSAGE(("library name is empty"));
        return JDWP_ERROR(TRANSPORT_LOAD);
    }
    
    /* First, look in sun.boot.library.path. This should find the standard
     *  dt_socket and dt_shmem transport libraries, or any library
     *  that was delivered with the J2SE.
     *  Note: Java property sun.boot.library.path contains a single directory.
     */
    libdir = gdata->property_sun_boot_library_path;
    if (libdir == NULL) {
        ERROR_MESSAGE(("Java property sun.boot.library.path is not set"));
        return JDWP_ERROR(TRANSPORT_LOAD);
    }
    handle = loadTransportLibrary(libdir, name);
    if (handle == NULL) {
        /* Second, look along the path used by the native dlopen/LoadLibrary
         *  functions. This should effectively try and load the simple
         *  library name, which will cause the default system library
         *  search technique to happen.
         *  We should only reach here if the transport library wasn't found
         *  in the J2SE directory, e.g. it's a custom transport library
         *  not installed in the J2SE like dt_socket and dt_shmem is.
         *
         *  Note: Why not use java.library.path? Several reasons:
         *        a) This matches existing agentlib search
         *        b) These are technically not JNI libraries
         */
        handle = loadTransportLibrary("", name);
    }

    /* See if a library was found with this name */
    if (handle == NULL) {
        ERROR_MESSAGE(("transport library not found: %s", name));
        return JDWP_ERROR(TRANSPORT_LOAD);
    } 
    /* Find the onLoad address */
    onLoad = findTransportOnLoad(handle);
    if (onLoad == NULL) {
        ERROR_MESSAGE(("transport library missing onLoad entry: %s", name));
        return JDWP_ERROR(TRANSPORT_LOAD);
    } 

    /* Get transport interface */
    env = getEnv();
    if ( env != NULL ) {
        jdwpTransportEnv *t;
        JavaVM           *jvm;
        jint              ver;
        
        JNI_FUNC_PTR(env,GetJavaVM)(env, &jvm);
        ver = (*onLoad)(jvm, &callback, JDWPTRANSPORT_VERSION_1_0, &t);
        if (ver != JNI_OK) {
            switch (ver) {
                case JNI_ENOMEM : 
                    ERROR_MESSAGE(("insufficient memory to complete initialization"));
                    break;

                case JNI_EVERSION :
                    ERROR_MESSAGE(("transport doesn't recognize version %x",
                        JDWPTRANSPORT_VERSION_1_0));
                    break;

                case JNI_EEXIST :
                    ERROR_MESSAGE(("transport doesn't support multiple environments"));
                    break;

                default:
                    ERROR_MESSAGE(("unrecognized error %d from transport", ver));
                    break;
            }

            return JDWP_ERROR(TRANSPORT_INIT);
        }
        (*t)->_handle = handle;
        *transportPtr = t;
    } else {
        return JDWP_ERROR(TRANSPORT_LOAD);
    } 
    
    return JDWP_ERROR(NONE);
}

static void 
connectionInitiated(jdwpTransportEnv *t)
{
    jint isValid = JNI_FALSE;

    debugMonitorEnter(listenerLock);
    
    /*
     * Don't allow a connection until initialization is complete
     */
    debugInit_waitInitComplete();

    /* Are we the first transport to get a connection? */

    if (transport == NULL) {
        transport = t;
        isValid = JNI_TRUE;
    } else {
        if (transport == t) {
            /* connected with the same transport as before */
            isValid = JNI_TRUE;
        } else {
            /*
             * Another transport got a connection - multiple transports
             * not fully supported yet so shouldn't get here.
             */
            (*t)->Close(t);
            JDI_ASSERT(JNI_FALSE);
        }
    }

    if (isValid) {
        debugMonitorNotifyAll(listenerLock);
    }

    debugMonitorExit(listenerLock);

    if (isValid) {
        debugLoop_run();
    }

}

/*
 * Set the transport property (sun.jdwp.listenerAddress) to the 
 * specified value.
 */
static void
setTransportProperty(JNIEnv* env, char* value) { 
    char* prop_value = (value == NULL) ? "" : value;
    setAgentPropertyValue(env, "sun.jdwp.listenerAddress", prop_value);
}

void
transport_waitForConnection(void)
{
    /*
     * If the VM is suspended on debugger initialization, we wait 
     * for a connection before continuing. This ensures that all
     * events are delivered to the debugger. (We might as well do this
     * this since the VM won't continue until a remote debugger attaches
     * and resumes it.) If not suspending on initialization, we must
     * just drop any packets (i.e. events) so that the VM can continue
     * to run. The debugger may not attach until much later.
     */
    if (debugInit_suspendOnInit()) {
        debugMonitorEnter(listenerLock);
        while (transport == NULL) {
            debugMonitorWait(listenerLock);
        }
        debugMonitorExit(listenerLock);
    }
}

static void JNICALL
acceptThread(jvmtiEnv* jvmti_env, JNIEnv* jni_env, void* arg) 
{
    TransportInfo *info;
    jdwpTransportEnv *t;
    jdwpTransportError rc;

    LOG_MISC(("Begin accept thread"));

    info = (TransportInfo*)(void*)arg;
    t = info->transport;

    rc = (*t)->Accept(t, info->timeout, 0);

    /* System property no longer needed */
    setTransportProperty(jni_env, NULL);

    if (rc != JDWPTRANSPORT_ERROR_NONE) {
        /*
         * If accept fails it probably means a timeout, or another fatal error
         * We thus exit the VM after stopping the listener.
         */
        printLastError(t, rc);
        (*t)->StopListening(t);