/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code 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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code 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 in the LICENSE file that

 * accompanied this code).

 *

 * 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 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

/*

 * eventFilter

 *

 * This module handles event filteration and the enabling/disabling

 * of the corresponding events. Used for filters on JDI EventRequests

 * and also internal requests.  Our data is in a private hidden section

 * of the HandlerNode's data.  See comment for enclosing

 * module eventHandler.

 */

#include "util.h"

#include "eventFilter.h"

#include "eventFilterRestricted.h"

#include "eventHandlerRestricted.h"

#include "stepControl.h"

#include "threadControl.h"

#include "SDE.h"

typedef struct ClassFilter {

    jclass clazz;

} ClassFilter;

typedef struct LocationFilter {

    jclass clazz;

    jmethodID method;

    jlocation location;

} LocationFilter;

typedef struct ThreadFilter {

    jthread thread;

} ThreadFilter;

typedef struct CountFilter {

    jint count;

} CountFilter;

typedef struct ConditionalFilter {

    jint exprID;

} ConditionalFilter;

typedef struct FieldFilter {

    jclass clazz;

    jfieldID field;

} FieldFilter;

typedef struct ExceptionFilter {

    jclass exception;

    jboolean caught;

    jboolean uncaught;

} ExceptionFilter;

typedef struct InstanceFilter {

    jobject instance;

} InstanceFilter;

typedef struct StepFilter {

    jint size;

    jint depth;

    jthread thread;

} StepFilter;

typedef struct MatchFilter {

    char *classPattern;

} MatchFilter;

typedef struct SourceNameFilter {

    char *sourceNamePattern;

} SourceNameFilter;

typedef struct Filter_ {

    jbyte modifier;

    union {

        struct ClassFilter ClassOnly;

        struct LocationFilter LocationOnly;

        struct ThreadFilter ThreadOnly;

        struct CountFilter Count;

        struct ConditionalFilter Conditional;

        struct FieldFilter FieldOnly;

        struct ExceptionFilter ExceptionOnly;

        struct InstanceFilter InstanceOnly;

        struct StepFilter Step;

        struct MatchFilter ClassMatch;

        struct MatchFilter ClassExclude;

        struct SourceNameFilter SourceNameOnly;

    } u;

} Filter;

/* The filters array is allocated to the specified filterCount.

 * Theoretically, some compiler could do range checking on this

 * array - so, we define it to have a ludicrously large size so

 * that this range checking won't get upset.

 *

 * The actual allocated number of bytes is computed using the

 * offset of "filters" and so is not effected by this number.

 */

#define MAX_FILTERS 10000

typedef struct EventFilters_ {

    jint filterCount;

    Filter filters[MAX_FILTERS];

} EventFilters;

typedef struct EventFilterPrivate_HandlerNode_ {

    EventHandlerRestricted_HandlerNode   not_for_us;

    EventFilters                         ef;

} EventFilterPrivate_HandlerNode;

/**

 * The following macros extract filter info (EventFilters) from private

 * data at the end of a HandlerNode

 */

#define EVENT_FILTERS(node) (&(((EventFilterPrivate_HandlerNode*)(void*)node)->ef))

#define FILTER_COUNT(node)  (EVENT_FILTERS(node)->filterCount)

#define FILTERS_ARRAY(node) (EVENT_FILTERS(node)->filters)

#define FILTER(node,index)  ((FILTERS_ARRAY(node))[index])

#define NODE_EI(node)          (node->ei)

/***** filter set-up / destruction *****/

/**

 * Allocate a HandlerNode.

 * We do it because eventHandler doesn't know how big to make it.

 */

HandlerNode *

eventFilterRestricted_alloc(jint filterCount)

{

    /*LINTED*/

    size_t size = offsetof(EventFilterPrivate_HandlerNode, ef) +

                  offsetof(EventFilters, filters) +

                  (filterCount * (int)sizeof(Filter));

    HandlerNode *node = jvmtiAllocate((jint)size);

    if (node != NULL) {

        int i;

        Filter *filter;

        (void)memset(node, 0, size);

        FILTER_COUNT(node) = filterCount;

        /* Initialize all modifiers

         */

        for (i = 0, filter = FILTERS_ARRAY(node);

                                    i < filterCount;

                                    i++, filter++) {

            filter->modifier = JDWP_REQUEST_NONE;

        }

    }

    return node;

}

/**

 * Free up global refs held by the filter.

 * free things up at the JNI level if needed.

 */

static jvmtiError

clearFilters(HandlerNode *node)

{

    JNIEnv *env = getEnv();

    jint i;

    jvmtiError error = JVMTI_ERROR_NONE;

    Filter *filter = FILTERS_ARRAY(node);

    for (i = 0; i < FILTER_COUNT(node); ++i, ++filter) {

        switch (filter->modifier) {

            case JDWP_REQUEST_MODIFIER(ThreadOnly):

                if ( filter->u.ThreadOnly.thread != NULL ) {

                    tossGlobalRef(env, &(filter->u.ThreadOnly.thread));

                }

                break;

            case JDWP_REQUEST_MODIFIER(LocationOnly):

                tossGlobalRef(env, &(filter->u.LocationOnly.clazz));

                break;

            case JDWP_REQUEST_MODIFIER(FieldOnly):

                tossGlobalRef(env, &(filter->u.FieldOnly.clazz));

                break;

            case JDWP_REQUEST_MODIFIER(ExceptionOnly):

                if ( filter->u.ExceptionOnly.exception != NULL ) {

                    tossGlobalRef(env, &(filter->u.ExceptionOnly.exception));

                }

                break;

            case JDWP_REQUEST_MODIFIER(InstanceOnly):

                if ( filter->u.InstanceOnly.instance != NULL ) {

                    tossGlobalRef(env, &(filter->u.InstanceOnly.instance));

                }

                break;

            case JDWP_REQUEST_MODIFIER(ClassOnly):

                tossGlobalRef(env, &(filter->u.ClassOnly.clazz));

                break;

            case JDWP_REQUEST_MODIFIER(ClassMatch):

                jvmtiDeallocate(filter->u.ClassMatch.classPattern);

                break;

            case JDWP_REQUEST_MODIFIER(ClassExclude):

                jvmtiDeallocate(filter->u.ClassExclude.classPattern);

                break;

            case JDWP_REQUEST_MODIFIER(Step): {

                jthread thread = filter->u.Step.thread;

                error = stepControl_endStep(thread);

                if (error == JVMTI_ERROR_NONE) {

                    tossGlobalRef(env, &(filter->u.Step.thread));

                }

                break;

            }

        }

    }

    if (error == JVMTI_ERROR_NONE) {

        FILTER_COUNT(node) = 0; /* blast so we don't clear again */

    }

    return error;

}

/***** filtering *****/

/*

 * Match a string against a wildcard

 * string pattern.

 */

static jboolean

patternStringMatch(char *classname, const char *pattern)

{

    int pattLen;

    int compLen;

    char *start;

    int offset;

    if ( pattern==NULL || classname==NULL ) {

        return JNI_FALSE;

    }

    pattLen = (int)strlen(pattern);

    if ((pattern[0] != '*') && (pattern[pattLen-1] != '*')) {

        /* An exact match is required when there is no *: bug 4331522 */

        return strcmp(pattern, classname) == 0;

    } else {

        compLen = pattLen - 1;

        offset = (int)strlen(classname) - compLen;

        if (offset < 0) {

            return JNI_FALSE;

        } else {

            if (pattern[0] == '*') {

                pattern++;

                start = classname + offset;

            }  else {

                start = classname;

            }

            return strncmp(pattern, start, compLen) == 0;

        }

    }

}

/* Return the object instance in which the event occurred */

/* Return NULL if static or if an error occurs */

static jobject

eventInstance(EventInfo *evinfo)

{

    jobject     object          = NULL;

    jthread     thread          ;

    jmethodID   method          ;

    jint        modifiers       = 0;

    jvmtiError  error;

    switch (evinfo->ei) {

        case EI_SINGLE_STEP:

        case EI_BREAKPOINT:

        case EI_FRAME_POP:

        case EI_METHOD_ENTRY:

        case EI_METHOD_EXIT:

        case EI_EXCEPTION:

        case EI_EXCEPTION_CATCH:

        case EI_MONITOR_CONTENDED_ENTER:

        case EI_MONITOR_CONTENDED_ENTERED:

        case EI_MONITOR_WAIT:

        case EI_MONITOR_WAITED:

            thread      = evinfo->thread;

            method      = evinfo->method;

            break;

        case EI_FIELD_ACCESS:

        case EI_FIELD_MODIFICATION:

            object = evinfo->object;

            return object;

        default:

            return object; /* NULL */

    }

    error = methodModifiers(method, &modifiers);

    /* fail if error or static (0x8) */

    if (error == JVMTI_ERROR_NONE && thread!=NULL && (modifiers & 0x8) == 0) {

        FrameNumber fnum            = 0;

        /* get slot zero object "this" */

        error = JVMTI_FUNC_PTR(gdata->jvmti,GetLocalObject)

                    (gdata->jvmti, thread, fnum, 0, &object);

        if (error != JVMTI_ERROR_NONE)

            object = NULL;

    }

    return object;

}

/*

 * Determine if this event is interesting to this handler.

 * Do so by checking each of the handler's filters.

 * Return false if any of the filters fail,

 * true if the handler wants this event.

 * Anyone modifying this function should check

 * eventFilterRestricted_passesUnloadFilter and

 * eventFilter_predictFiltering as well.

 *

 * If shouldDelete is returned true, a count filter has expired

 * and the corresponding node should be deleted.

 */

jboolean

eventFilterRestricted_passesFilter(JNIEnv *env,

                                   char *classname,

                                   EventInfo *evinfo,

                                   HandlerNode *node,

                                   jboolean *shouldDelete)

{

    jthread thread;

    jclass clazz;

    jmethodID method;

    Filter *filter = FILTERS_ARRAY(node);

    int i;

    *shouldDelete = JNI_FALSE;

    thread = evinfo->thread;

    clazz = evinfo->clazz;

    method = evinfo->method;

    /*

     * Suppress most events if they happen in debug threads

     */

    if ((evinfo->ei != EI_CLASS_PREPARE) &&

        (evinfo->ei != EI_GC_FINISH) &&

        (evinfo->ei != EI_CLASS_LOAD) &&

        threadControl_isDebugThread(thread)) {

        return JNI_FALSE;

    }

    for (i = 0; i < FILTER_COUNT(node); ++i, ++filter) {

        switch (filter->modifier) {

            case JDWP_REQUEST_MODIFIER(ThreadOnly):

                if (!isSameObject(env, thread, filter->u.ThreadOnly.thread)) {

                    return JNI_FALSE;

                }

                break;

            case JDWP_REQUEST_MODIFIER(ClassOnly):

                /* Class filters catch events in the specified

                 * class and any subclass/subinterface.

                 */

                if (!JNI_FUNC_PTR(env,IsAssignableFrom)(env, clazz,

                               filter->u.ClassOnly.clazz)) {

                    return JNI_FALSE;

                }

                break;

            /* This is kinda cheating assumming the event

             * fields will be in the same locations, but it is

             * true now.

             */

            case JDWP_REQUEST_MODIFIER(LocationOnly):

                if  (evinfo->method !=

                          filter->u.LocationOnly.method ||

                     evinfo->location !=

                          filter->u.LocationOnly.location ||

                     !isSameObject(env, clazz, filter->u.LocationOnly.clazz)) {

                    return JNI_FALSE;

                }

                break;

            case JDWP_REQUEST_MODIFIER(FieldOnly):

                /* Field watchpoints can be triggered from the

                 * declared class or any subclass/subinterface.

                 */

                if ((evinfo->u.field_access.field !=

                     filter->u.FieldOnly.field) ||

                    !isSameObject(env, evinfo->u.field_access.field_clazz,

                               filter->u.FieldOnly.clazz)) {

                    return JNI_FALSE;

                }

                break;

            case JDWP_REQUEST_MODIFIER(ExceptionOnly):

                /* do we want caught/uncaught exceptions */

                if (!((evinfo->u.exception.catch_clazz == NULL)?

                      filter->u.ExceptionOnly.uncaught :

                      filter->u.ExceptionOnly.caught)) {

                    return JNI_FALSE;

                }

                /* do we care about exception class */

                if (filter->u.ExceptionOnly.exception != NULL) {

                    jclass exception = evinfo->object;

                    /* do we want this exception class */

                    if (!JNI_FUNC_PTR(env,IsInstanceOf)(env, exception,

                            filter->u.ExceptionOnly.exception)) {

                        return JNI_FALSE;

                    }

                }

                break;

            case JDWP_REQUEST_MODIFIER(InstanceOnly): {

                jobject eventInst = eventInstance(evinfo);

                jobject filterInst = filter->u.InstanceOnly.instance;

                /* if no error and doesn't match, don't pass

                 * filter

                 */

                if (eventInst != NULL &&

                      !isSameObject(env, eventInst, filterInst)) {

                    return JNI_FALSE;

                }

                break;

            }

            case JDWP_REQUEST_MODIFIER(Count): {

                JDI_ASSERT(filter->u.Count.count > 0);

                if (--filter->u.Count.count > 0) {

                    return JNI_FALSE;

                }

                *shouldDelete = JNI_TRUE;

                break;

            }

            case JDWP_REQUEST_MODIFIER(Conditional):

/***

                if (...  filter->u.Conditional.exprID ...) {

                    return JNI_FALSE;

                }

***/

                break;

        case JDWP_REQUEST_MODIFIER(ClassMatch): {

            if (!patternStringMatch(classname,

                       filter->u.ClassMatch.classPattern)) {

                return JNI_FALSE;

            }

            break;

        }

        case JDWP_REQUEST_MODIFIER(ClassExclude): {

            if (patternStringMatch(classname,

                      filter->u.ClassExclude.classPattern)) {

                return JNI_FALSE;

            }

            break;

        }

        case JDWP_REQUEST_MODIFIER(Step):

                if (!isSameObject(env, thread, filter->u.Step.thread)) {

                    return JNI_FALSE;

                }

                if (!stepControl_handleStep(env, thread, clazz, method)) {

                    return JNI_FALSE;

                }

                break;

          case JDWP_REQUEST_MODIFIER(SourceNameMatch): {

              char* desiredNamePattern = filter->u.SourceNameOnly.sourceNamePattern;

              if (!searchAllSourceNames(env, clazz,

                           desiredNamePattern) == 1) {

                  /* The name isn't in the SDE; try the sourceName in the ref

                   * type

                   */

                  char *sourceName = 0;

                  jvmtiError error = JVMTI_FUNC_PTR(gdata->jvmti,GetSourceFileName)

                                            (gdata->jvmti, clazz, &sourceName);

                  if (error == JVMTI_ERROR_NONE &&

                      sourceName != 0 &&

                      patternStringMatch(sourceName, desiredNamePattern)) {

                          // got a hit - report the event

                          jvmtiDeallocate(sourceName);

                          break;

                  }

                  // We have no match, we have no source file name,

                  // or we got a JVM TI error. Don't report the event.

                  jvmtiDeallocate(sourceName);

                  return JNI_FALSE;

              }

              break;

          }

        default:

            EXIT_ERROR(AGENT_ERROR_ILLEGAL_ARGUMENT,"Invalid filter modifier");

            return JNI_FALSE;

        }

    }

    return JNI_TRUE;

}

/* Determine if this event is interesting to this handler.  Do so

 * by checking each of the handler's filters.  Return false if any

 * of the filters fail, true if the handler wants this event.

 * Special version of filter for unloads since they don't have an

 * event structure or a jclass.

 *

 * If shouldDelete is returned true, a count filter has expired

 * and the corresponding node should be deleted.

 */

jboolean