#include
#include
#include
#include
#include
#include
#include
#include
#include
#define LOCK pthread_mutex_lock(&lock)
#define UNLOCK pthread_mutex_unlock(&lock)
#define PRINT(STR, ...) LOCK;fprintf(stderr, STR, __VA_ARGS__);UNLOCK
#define MAXROWS 100
using namespace std;
/* 行结构 */
struct Row {
int num;
string info;
};
/* 主键索引结构 */
struct PK_Idx {
Row row;
pthread_mutex_t lock;//行锁
};
/* 表结构 */
struct Table {
multimap<int, PK_Idx> pk_idx;
multimap<int, int> num_idx;
multimap<string, int> info_idx;
Row rows[MAXROWS];
pthread_mutex_t lock;//表锁
};
Table table;
int pid;
//全局锁
pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
/* 随机字符 */
char randChar() {
return rand()%26+'A';
}
/* 随机字符串 */
void randString(string &col, int len) {
col = "";
for(int i=0; i<len; ++i) {
col += randChar();
}
}
/* 初始化数据 */
void init() {
pid = 0;
PK_Idx pk;
srand((unsigned)time(0));
//初始化表数据
for(int i=0; i<MAXROWS; ++i) {
pk.row.num = rand()%MAXROWS;
randString(pk.row.info, rand()%10+1);
//初始化行锁
pk.lock = PTHREAD_MUTEX_INITIALIZER;
//写入表数据
table.rows[i].num = pk.row.num;
table.rows[i].info = pk.row.info;
//写入索引
table.pk_idx.insert(pair<int, PK_Idx>(i, pk));
table.num_idx.insert(pair<int, int>(pk.row.num, i));
table.info_idx.insert(pair<string, int>(pk.row.info, i));
}
//初始化表锁
table.lock = PTHREAD_MUTEX_INITIALIZER;
}
/*获取范围数据*/
void select_num(int begin, int end) {
int id;
int cur_pid;
multimap<int,int>::iterator it, itlow, itup;
PK_Idx *pk;
/* 按字段范围查找ID */
itlow = table.num_idx.lower_bound (begin);
itup = table.num_idx.upper_bound (end);
LOCK;
cur_pid = pid++;
UNLOCK;
PRINT("%d : * Start Select:%d,%d *\n", cur_pid, begin, end);
for (it=itlow; it!=itup; ++it) {
id = it->second;
pk = &(table.pk_idx.find(id)->second);//根据ID去查主键索引
pthread_mutex_lock(&(pk->lock));//在主键索引上加锁
PRINT("%d : LOCK Row %d: %d\t%s\n", cur_pid, id, pk->row.num, pk->row.info.c_str());
Sleep(500);
}
for (it=itlow; it!=itup; ++it) {
id = it->second;
pk = &(table.pk_idx.find(id)->second);
PRINT("%d : UNLOCK Row %d\n", cur_pid, id);
pthread_mutex_unlock(&(pk->lock));//使用完毕依次释放锁
}
PRINT("%d : * Select Finished! *\n", cur_pid);
}
/*修改范围数据*/
void update_num(int begin, int end) {
int id;
int cur_pid;
multimap<int,int>::iterator it, itlow, itup;
PK_Idx *pk;
itlow = table.num_idx.lower_bound (begin);
itup = table.num_idx.upper_bound (end);
LOCK;
cur_pid = pid++;
UNLOCK;
PRINT("%d : * Start Update:%d,%d *\n", cur_pid, begin, end);
for (it=itlow; it!=itup; ++it) {
id = it->second;
pk = &(table.pk_idx.find(id)->second);
pthread_mutex_lock(&(pk->lock));
PRINT("%d : LOCK Row %d: %d\t%s\n", cur_pid, id, pk->row.num, pk->row.info.c_str());
Sleep(500);
}
for (it=itlow; it!=itup; ++it) {
id = it->second;
pk = &(table.pk_idx.find(id)->second);
PRINT("%d : UNLOCK Row %d\n", cur_pid, id);
pthread_mutex_unlock(&(pk->lock));
}
PRINT("%d : * Update Finished! *\n", cur_pid);
}
void* test_select(void *) {
int begin, end;
srand((unsigned)time(0));
while(1) {
begin = rand()%(MAXROWS/2);
end = begin+rand()%(MAXROWS/2);
select_num(begin, end);
Sleep(500);
}
}
void* test_update(void *) {
int begin, end;
srand((unsigned)time(0));
while(1) {
begin = rand()%(MAXROWS/5);
end = begin+rand()%(MAXROWS/5);
update_num(begin, end);
Sleep(500);
}
}
void test() {
pthread_t id[2];
if(pthread_create(&id[0], NULL, test_select, NULL) != 0)
{
PRINT("%s", "Create Thread Error!\n");
}
if(pthread_create(&id[1], NULL, test_update, NULL) != 0)
{
PRINT("%s", "Create Thread Error!\n");
}
while(1){
Sleep(500);
}
}
int main() {
init();
test();
return 0;
}
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