java_locked.c
上传用户:tsgydb
上传日期:2007-04-14
资源大小:10674k
文件大小:8k
- /*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1997, 1998, 1999, 2000
- * Sleepycat Software. All rights reserved.
- */
- #include "db_config.h"
- #ifndef lint
- static const char revid[] = "$Id: java_locked.c,v 11.11 2000/10/25 19:54:55 dda Exp $";
- #endif /* not lint */
- #include <jni.h>
- #include <errno.h>
- #include <stdlib.h>
- #include <string.h>
- #include "db.h"
- #include "java_util.h"
- /****************************************************************
- *
- * Implementation of class LockedDBT
- *
- */
- int
- jdbt_lock(JDBT *jdbt, JNIEnv *jnienv, jobject obj, OpKind kind)
- {
- DBT *dbt;
- jdbt->obj_ = obj;
- jdbt->do_realloc_ = 0;
- jdbt->kind_ = kind;
- jdbt->java_array_len_= 0;
- jdbt->java_data_ = 0;
- jdbt->before_data_ = 0;
- jdbt->has_error_ = 0;
- jdbt->dbt = (DBT_JAVAINFO *)get_private_dbobj(jnienv, name_DBT, obj);
- if (!verify_non_null(jnienv, jdbt->dbt)) {
- jdbt->has_error_ = 1;
- return (EINVAL);
- }
- dbt = &jdbt->dbt->dbt;
- if (kind == outOp &&
- (dbt->flags & (DB_DBT_USERMEM | DB_DBT_MALLOC | DB_DBT_REALLOC)) == 0) {
- report_exception(jnienv,
- "Dbt.flags must be set to Db.DB_DBT_USERMEM, "
- "Db.DB_DBT_MALLOC or Db.DB_DBT_REALLOC",
- 0, 0);
- jdbt->has_error_ = 1;
- return (EINVAL);
- }
- /* If this is requested to be realloc, we cannot use the
- * underlying realloc, because the array we will pass in
- * is not allocated by us, but the Java VM, so it cannot
- * be successfully realloced. We simulate the reallocation,
- * by using USERMEM and reallocating the java array when a
- * ENOMEM error occurs. We change the flags during the operation,
- * and they are reset when the operation completes (in the
- * LockedDBT destructor.
- */
- if ((dbt->flags & DB_DBT_REALLOC) != 0) {
- dbt->flags &= ~DB_DBT_REALLOC;
- dbt->flags |= DB_DBT_USERMEM;
- jdbt->do_realloc_ = 1;
- }
- if ((dbt->flags & DB_DBT_USERMEM) || kind != outOp) {
- /* If writing with DB_DBT_USERMEM/REALLOC
- * or it's a set (or get/set) operation,
- * then the data should point to a java array.
- * Note that outOp means data is coming out of the database
- * (it's a get). inOp means data is going into the database
- * (either a put, or a key input).
- */
- if (!jdbt->dbt->array_) {
- report_exception(jnienv, "Dbt.data is null", 0, 0);
- jdbt->has_error_ = 1;
- return (EINVAL);
- }
- /* Verify other parameters */
- jdbt->java_array_len_ = (*jnienv)->GetArrayLength(jnienv, jdbt->dbt->array_);
- if (jdbt->dbt->offset_ < 0 ) {
- report_exception(jnienv, "Dbt.offset illegal", 0, 0);
- jdbt->has_error_ = 1;
- return (EINVAL);
- }
- if (dbt->ulen + jdbt->dbt->offset_ > jdbt->java_array_len_) {
- report_exception(jnienv,
- "Dbt.ulen + Dbt.offset greater than array length", 0, 0);
- jdbt->has_error_ = 1;
- return (EINVAL);
- }
- jdbt->java_data_ = (*jnienv)->GetByteArrayElements(jnienv, jdbt->dbt->array_,
- (jboolean *)0);
- dbt->data = jdbt->before_data_ = jdbt->java_data_ + jdbt->dbt->offset_;
- }
- else {
- /* If writing with DB_DBT_MALLOC, then the data is
- * allocated by DB.
- */
- dbt->data = jdbt->before_data_ = 0;
- }
- return (0);
- }
- /* The LockedDBT destructor is called when the java handler returns
- * to the user, since that's when the LockedDBT objects go out of scope.
- * Since it is thus called after any call to the underlying database,
- * it copies any information from temporary structures back to user
- * accessible arrays, and of course must free memory and remove references.
- */
- void
- jdbt_unlock(JDBT *jdbt, JNIEnv *jnienv)
- {
- DBT *dbt;
- dbt = &jdbt->dbt->dbt;
- /* Fix up the flags if we changed them. */
- if (jdbt->do_realloc_) {
- dbt->flags &= ~DB_DBT_USERMEM;
- dbt->flags |= DB_DBT_REALLOC;
- }
- if ((dbt->flags & (DB_DBT_USERMEM | DB_DBT_REALLOC)) ||
- jdbt->kind_ == inOp) {
- /* If writing with DB_DBT_USERMEM/REALLOC or it's a set
- * (or get/set) operation, then the data may be already in
- * the java array, in which case, we just need to release it.
- * If DB didn't put it in the array (indicated by the
- * dbt->data changing), we need to do that
- */
- if (jdbt->before_data_ != jdbt->java_data_) {
- (*jnienv)->SetByteArrayRegion(jnienv,
- jdbt->dbt->array_,
- jdbt->dbt->offset_,
- dbt->ulen,
- jdbt->before_data_);
- }
- (*jnienv)->ReleaseByteArrayElements(jnienv, jdbt->dbt->array_, jdbt->java_data_, 0);
- dbt->data = 0;
- }
- if ((dbt->flags & DB_DBT_MALLOC) && jdbt->kind_ != inOp) {
- /* If writing with DB_DBT_MALLOC, then the data was allocated
- * by DB. If dbt->data is zero, it means an error occurred
- * (and should have been already reported).
- */
- if (dbt->data) {
- /* Release any old references. */
- dbjit_release(jdbt->dbt, jnienv);
- /* In the case of SET_RANGE, the key is inOutOp
- * and when not found, its data will be left as
- * its original value. Only copy and free it
- * here if it has been allocated by DB
- * (dbt->data has changed).
- */
- if (dbt->data != jdbt->before_data_) {
- jdbt->dbt->array_ = (jbyteArray)
- NEW_GLOBAL_REF(jnienv,
- (*jnienv)->NewByteArray(jnienv,
- dbt->size));
- jdbt->dbt->offset_ = 0;
- (*jnienv)->SetByteArrayRegion(jnienv,
- jdbt->dbt->array_, 0, dbt->size,
- (jbyte *)dbt->data);
- free(dbt->data);
- dbt->data = 0;
- }
- }
- }
- }
- /* Realloc the java array to receive data if the DBT was marked
- * for realloc, and the last operation set the size field to an
- * amount greater than ulen.
- */
- int jdbt_realloc(JDBT *jdbt, JNIEnv *jnienv)
- {
- DBT *dbt;
- dbt = &jdbt->dbt->dbt;
- if (!jdbt->do_realloc_ || jdbt->has_error_ || dbt->size <= dbt->ulen)
- return (0);
- (*jnienv)->ReleaseByteArrayElements(jnienv, jdbt->dbt->array_, jdbt->java_data_, 0);
- dbjit_release(jdbt->dbt, jnienv);
- /* We allocate a new array of the needed size.
- * We'll set the offset to 0, as the old offset
- * really doesn't make any sense.
- */
- jdbt->java_array_len_ = dbt->ulen = dbt->size;
- jdbt->dbt->offset_ = 0;
- jdbt->dbt->array_ = (jbyteArray)
- NEW_GLOBAL_REF(jnienv, (*jnienv)->NewByteArray(jnienv, dbt->size));
- jdbt->java_data_ = (*jnienv)->GetByteArrayElements(jnienv,
- jdbt->dbt->array_,
- (jboolean *)0);
- dbt->data = jdbt->before_data_ = jdbt->java_data_;
- return (1);
- }
- /****************************************************************
- *
- * Implementation of class JSTR
- *
- */
- int
- jstr_lock(JSTR *js, JNIEnv *jnienv, jstring jstr)
- {
- js->jstr_ = jstr;
- if (jstr == 0)
- js->string = 0;
- else
- js->string = (*jnienv)->GetStringUTFChars(jnienv, jstr,
- (jboolean *)0);
- return (0);
- }
- void jstr_unlock(JSTR *js, JNIEnv *jnienv)
- {
- if (js->jstr_)
- (*jnienv)->ReleaseStringUTFChars(jnienv, js->jstr_, js->string);
- }
- /****************************************************************
- *
- * Implementation of class JSTRARRAY
- *
- */
- int
- jstrarray_lock(JSTRARRAY *jsa, JNIEnv *jnienv, jobjectArray arr)
- {
- int i;
- jsa->arr_ = arr;
- jsa->array = 0;
- if (arr != 0) {
- int count = (*jnienv)->GetArrayLength(jnienv, arr);
- const char **new_array =
- (const char **)malloc((sizeof(const char *))*(count+1));
- for (i=0; i<count; i++) {
- jstring jstr = (jstring)(*jnienv)->GetObjectArrayElement(jnienv, arr, i);
- if (jstr == 0) {
- /*
- * An embedded null in the string array
- * is treated as an endpoint.
- */
- new_array[i] = 0;
- break;
- }
- else {
- new_array[i] =
- (*jnienv)->GetStringUTFChars(jnienv, jstr, (jboolean *)0);
- }
- }
- new_array[count] = 0;
- jsa->array = new_array;
- }
- return (0);
- }
- void jstrarray_unlock(JSTRARRAY *jsa, JNIEnv *jnienv)
- {
- int i;
- jstring jstr;
- if (jsa->arr_) {
- int count = (*jnienv)->GetArrayLength(jnienv, jsa->arr_);
- for (i=0; i<count; i++) {
- if (jsa->array[i] == 0)
- break;
- jstr = (jstring)(*jnienv)->GetObjectArrayElement(jnienv, jsa->arr_, i);
- (*jnienv)->ReleaseStringUTFChars(jnienv, jstr, jsa->array[i]);
- }
- free((void*)jsa->array);
- }
- }