#include <stdlib.h>
#include <jni.h>
#include "native_state.h"
#define DEFAULT_TABLE_SIZE 97
struct state_table *
init_state_table_with_size (JNIEnv *env, jclass clazz, jint size)
{
struct state_table *table;
jfieldID hash;
jclass clazz_g;
hash = (*env)->GetFieldID (env, clazz, "native_state", "I");
if (hash == NULL)
return NULL;
clazz_g = (*env)->NewGlobalRef (env, clazz);
if (clazz_g == NULL)
return NULL;
table = (struct state_table *) malloc (sizeof (struct state_table));
table->size = size;
table->head = (struct state_node **) calloc (sizeof (struct state_node *),
table->size);
table->hash = hash;
table->clazz = clazz_g;
return table;
}
struct state_table *
init_state_table (JNIEnv *env, jclass clazz)
{
return init_state_table_with_size (env, clazz, DEFAULT_TABLE_SIZE);
}
static void *
remove_node (struct state_node **head, jint obj_id)
{
struct state_node *back_ptr = NULL;
struct state_node *node = *head;
while (node != NULL)
{
if (node->key == obj_id)
{
void *return_value;
if (back_ptr == NULL)
*head = node->next;
else
back_ptr->next = node->next;
return_value = node->c_state;
free (node);
return return_value;
}
back_ptr = node;
node = node->next;
}
return NULL;
}
static void *
get_node (struct state_node **head, jint obj_id)
{
struct state_node *back_ptr = NULL;
struct state_node *node = *head;
while (node != NULL)
{
if (node->key == obj_id)
{
if (back_ptr != NULL)
{
back_ptr->next = node->next;
node->next = *head;
*head = node;
}
return node->c_state;
}
back_ptr = node;
node = node->next;
}
return NULL;
}
static void
add_node (struct state_node **head, jint obj_id, void *state)
{
struct state_node *node = *head;
struct state_node *back_ptr = NULL;
struct state_node *new_node;
if (node != NULL)
{
while (node->next != NULL && obj_id != node->key)
{
back_ptr = node;
node = node->next;
}
if (node->key == obj_id)
{
if (back_ptr != NULL)
{
back_ptr->next = node->next;
node->next = *head;
}
node->c_state = state;
return;
}
}
new_node = (struct state_node *) malloc (sizeof (struct state_node));
new_node->key = obj_id;
new_node->c_state = state;
new_node->next = *head;
*head = new_node;
}
void
set_state_oid (JNIEnv *env, jobject lock, struct state_table *table,
jint obj_id, void *state)
{
jint hash;
hash = obj_id % table->size;
(*env)->MonitorEnter (env, lock);
add_node (&table->head[hash], obj_id, state);
(*env)->MonitorExit (env, lock);
}
void *
get_state_oid (JNIEnv *env, jobject lock, struct state_table *table,
jint obj_id)
{
jint hash;
void *return_value;
hash = obj_id % table->size;
(*env)->MonitorEnter (env, lock);
return_value = get_node (&table->head[hash], obj_id);
(*env)->MonitorExit (env, lock);
return return_value;
}
void *
remove_state_oid (JNIEnv *env, jobject lock, struct state_table *table,
jint obj_id)
{
jint hash;
void *return_value;
hash = obj_id % table->size;
(*env)->MonitorEnter (env, lock);
return_value = remove_node (&table->head[hash], obj_id);
(*env)->MonitorExit (env, lock);
return return_value;
}
int
set_state (JNIEnv *env, jobject obj, struct state_table *table, void *state)
{
jint obj_id;
obj_id = (*env)->GetIntField (env, obj, table->hash);
if ((*env)->ExceptionOccurred (env) != NULL)
return -1;
set_state_oid (env, table->clazz, table, obj_id, state);
return 0;
}
void *
get_state (JNIEnv *env, jobject obj, struct state_table *table)
{
jint obj_id;
obj_id = (*env)->GetIntField (env, obj, table->hash);
if ((*env)->ExceptionOccurred (env) != NULL)
return NULL;
return get_state_oid (env, table->clazz, table, obj_id);
}
void *
remove_state_slot (JNIEnv *env, jobject obj, struct state_table *table)
{
jint obj_id;
obj_id = (*env)->GetIntField (env, obj, table->hash);
if ((*env)->ExceptionOccurred (env) != NULL)
return NULL;
return remove_state_oid (env, table->clazz, table, obj_id);
}