让 “Thread_example1.pc” 代码在 Linux 平台下编译运行

Thread_example1.pc 是《Pro*C/C++ Programmer's Guide》( 10g Release 2 (10.2) ) 的一个多线程示例程序，但其是在UNIX平台下编写的，为能在Linux平台下编译运行，需要做一些改动。下面是Linux 平台下的改动版本。

/* * Name:        Thread_example1.pc * * Description: This program illustrates how to use threading in *      conjunction with precompilers. The program creates as many *      sessions as there are threads. Each thread executes zero or *      more transactions, that are specified in a transient *      structure called 'records'. * Requirements: *      The program requires a table 'ACCOUNTS' to be in the schema *      scott/tiger. The description of ACCOUNTS is: *  SQL> desc accounts *   Name                            Null?    Type *  ------------------------------- -------  ------ *  ACCOUNT                                  NUMBER(36) *  BALANCE                                  NUMBER(36,2) * *  For proper execution, the table should be filled with the accounts *      10001 to 10008. * * */#include <stdio.h>#include <stdlib.h>#include <string.h>#include <sqlca.h>#define      _EXC_OS_        _EXC__UNIX#define      _CMA_OS_        _CMA__UNIX#define  DCE_THREADS //[add] #ifdef DCE_THREADS  #include <pthread.h>#else  #include <thread.h>#endif/* Function prototypes */void   err_report();#ifdef DCE_THREADSvoid   do_transaction();#elsevoid   *do_transaction();#endifvoid   get_transaction();void   logon();void   logoff();#define CONNINFO "scott/tiger"#define THREADS  3 struct parameters { sql_context * ctx;  int thread_id;};typedef struct parameters parameters;struct record_log{  char action;   unsigned int from_account;   unsigned int to_account;   float  amount;};typedef struct record_log record_log;record_log records[]= { { 'M', 10001, 10002, 12.50 },                        { 'M', 10001, 10003, 25.00 },                        { 'M', 10001, 10003, 123.00 },                        { 'M', 10001, 10003, 125.00 },                        { 'M', 10002, 10006, 12.23 },                        { 'M', 10007, 10008, 225.23 },                        { 'M', 10002, 10008, 0.70 },                        { 'M', 10001, 10003, 11.30 },                        { 'M', 10003, 10002, 47.50 },                        { 'M', 10002, 10006, 125.00 },                        { 'M', 10007, 10008, 225.00 },                        { 'M', 10002, 10008, 0.70 },                        { 'M', 10001, 10003, 11.00 },                        { 'M', 10003, 10002, 47.50 },                        { 'M', 10002, 10006, 125.00 },                        { 'M', 10007, 10008, 225.00 },                        { 'M', 10002, 10008, 0.70 },                        { 'M', 10001, 10003, 11.00 },                        { 'M', 10003, 10002, 47.50 },                        { 'M', 10008, 10001, 1034.54}};static unsigned int trx_nr=0;#ifdef DCE_THREADSpthread_mutex_t mutex;#elsemutex_t mutex;#endif/********************************************************************* *  Main ********************************************************************/main(){  sql_context ctx[THREADS];#ifdef DCE_THREADS  pthread_t thread_id[THREADS];  pthread_attr_t status;#else  thread_t thread_id[THREADS];  int status;#endif  parameters params[THREADS];  int i;    EXEC SQL ENABLE THREADS;  EXEC SQL WHENEVER SQLERROR DO err_report(sqlca);  /* Create THREADS sessions by connecting THREADS times */  for(i=0;i<THREADS;i++)  {    printf("Start Session %d....",i);    EXEC SQL CONTEXT ALLOCATE :ctx[i];    logon(ctx[i],CONNINFO);  }  /*Create mutex for transaction retrieval */#ifdef DCE_THREADS  if (pthread_mutex_init(&mutex,NULL))#else  if (mutex_init(&mutex, USYNC_THREAD, NULL))#endif  {     printf("Can't initialize mutex\n");     exit(1);  }  /*Spawn threads*/  for(i=0;i<THREADS;i++)  {    params[i].ctx=ctx[i];    params[i].thread_id=i;    printf("Thread %d... ",i);#ifdef DCE_THREADS    if (pthread_create(&thread_id[i],NULL,        (void*)do_transaction,        (void*) ¶ms[i]))#else    if (status = thr_create    (NULL, 0, do_transaction, ¶ms[i], 0, &thread_id[i]))#endif      printf("Cant create thread %d\n",i);    else      printf("Created\n");  }  /* Logoff sessions....*/  for(i=0;i<THREADS;i++)  {     /*wait for thread to end */     printf("Thread %d ....",i);#ifdef DCE_THREADS     if (pthread_join(thread_id[i],NULL))       printf("Error when waiting for thread % to terminate\n", i);     else      printf("stopped\n");     printf("Detach thread...");     if (pthread_detach(thread_id[i]))       printf("Error detaching thread! \n");     else       printf("Detached!\n");#else     if (thr_join(thread_id[i], NULL, NULL))       printf("Error waiting for thread to terminate\n");#endif     printf("Stop Session %d....",i);     logoff(ctx[i]);     EXEC SQL CONTEXT FREE :ctx[i];  }  /*Destroys mutex*/#ifdef DCE_THREADS  if (pthread_mutex_destroy(&mutex))#else  if (mutex_destroy(&mutex))#endif  {    printf("Can't destroy mutex\n");    exit(1);  }}/********************************************************************* * Function: do_transaction * * Description:  This functions executes one transaction out of the  *               records array. The records array is 'managed' by *               the get_transaction function. * * ********************************************************************/#ifdef DCE_THREADSvoid do_transaction(params)#elsevoid *do_transaction(params)#endifparameters *params;{  struct sqlca sqlca;  record_log *trx;  sql_context ctx=params->ctx;  /* Done all transactions ? */  while (trx_nr < (sizeof(records)/sizeof(record_log)))  {    get_transaction(&trx);    EXEC SQL WHENEVER SQLERROR DO err_report(sqlca);    EXEC SQL CONTEXT USE :ctx;    printf("Thread %d executing transaction\n",params->thread_id);    switch(trx->action)    {      case 'M':  EXEC SQL UPDATE ACCOUNTS                          SET    BALANCE=BALANCE+:trx->amount                          WHERE  ACCOUNT=:trx->to_account;                 EXEC SQL UPDATE ACCOUNTS                          SET    BALANCE=BALANCE-:trx->amount                          WHERE  ACCOUNT=:trx->from_account;                 break;       default:  break;    }    EXEC SQL COMMIT;  }}/***************************************************************** * Function: err_report * * Description: This routine prints out the most recent error * ****************************************************************/void      err_report(sqlca)struct sqlca sqlca;{  if (sqlca.sqlcode < 0)   printf("\n%.*s\n\n",sqlca.sqlerrm.sqlerrml,sqlca.sqlerrm.sqlerrmc);  exit(1);}/***************************************************************** * Function: logon * * Description: Logs on to the database as USERNAME/PASSWORD * *****************************************************************/void      logon(ctx,connect_info)sql_context ctx;char * connect_info;{    EXEC SQL WHENEVER SQLERROR DO err_report(sqlca);    EXEC SQL CONTEXT USE :ctx;    EXEC SQL CONNECT :connect_info;    printf("Connected!\n");}/****************************************************************** * Function: logoff * * Description: This routine logs off the database * ******************************************************************/void      logoff(ctx)sql_context ctx;{    EXEC SQL WHENEVER SQLERROR DO err_report(sqlca);    EXEC SQL CONTEXT USE :ctx;    EXEC SQL COMMIT WORK RELEASE;    printf("Logged off!\n");}/****************************************************************** * Function: get_transaction * * Description: This routine returns the next transaction to process * ******************************************************************/void get_transaction(trx)record_log ** trx;{#ifdef DCE_THREADS  if (pthread_mutex_lock(&mutex))#else  if (mutex_lock(&mutex))#endif    printf("Can't lock mutex\n");  *trx=&records[trx_nr];  trx_nr++;#ifdef DCE_THREADS  if (pthread_mutex_unlock(&mutex))#else  if (mutex_unlock(&mutex))#endif    printf("Can't unlock mutex\n");}