[td-225] refactor shell code.

src/kit/shell/src/shellEngine.c

@@ -284,7 +284,7 @@ void shellRunCommandOnServer(TAOS *con, char command[]) {
   st = taosGetTimestampUs();
 
   TAOS_RES* pSql = taos_query(con, command);
-  result = pSql;  // set it into the global variable
+  atomic_store_ptr(&result, pSql);  // set the global TAOS_RES pointer
 
   if (taos_errno(pSql)) {
     taos_error(pSql);
@@ -295,7 +295,7 @@ void shellRunCommandOnServer(TAOS *con, char command[]) {
     fprintf(stdout, "Database changed.\n\n");
     fflush(stdout);
 
-    result = NULL;
+    atomic_store_ptr(&result, 0);
     taos_free_result(pSql);
     return;
   }
@@ -304,7 +304,7 @@ void shellRunCommandOnServer(TAOS *con, char command[]) {
     int error_no = 0;
     int numOfRows = shellDumpResult(pSql, fname, &error_no, printMode);
     if (numOfRows < 0) {
-      result = NULL;
+      atomic_store_ptr(&result, 0);
       taos_free_result(pSql);
       return;
     }
@@ -327,7 +327,7 @@ void shellRunCommandOnServer(TAOS *con, char command[]) {
     wordfree(&full_path);
   }
 
-  result = NULL;
+  atomic_store_ptr(&result, 0);
   taos_free_result(pSql);
 }
 
@@ -493,7 +493,6 @@ static int dumpResultToFile(const char* fname, TAOS_RES* tres) {
   } while( row != NULL);
 
   result = NULL;
-  //taos_free_result(tres);
   fclose(fp);
 
   return numOfRows;
@@ -798,8 +797,8 @@ void write_history() {
 }
 
 void taos_error(TAOS_RES *tres) {
+  atomic_store_ptr(&result, 0);
   fprintf(stderr, "\nDB error: %s\n", taos_errstr(tres));
-  result = NULL;
   taos_free_result(tres);
 }
 

src/kit/shell/src/shellMain.c

@@ -18,11 +18,10 @@
 
 pthread_t pid;
 
-// TODO: IMPLEMENT INTERRUPT HANDLER.
-void interruptHandler(int signum) {
+void shellQueryInterruptHandler(int signum) {
 #ifdef LINUX
-  taos_stop_query(result);
-  result = NULL;
+  void* pResHandle = atomic_val_compare_exchange_64(&result, result, 0);
+  taos_stop_query(pResHandle);
 #else
   printf("\nReceive ctrl+c or other signal, quit shell.\n");
   exit(0);
@@ -86,7 +85,7 @@ int main(int argc, char* argv[]) {
   struct sigaction act;
   memset(&act, 0, sizeof(struct sigaction));
   
-  act.sa_handler = interruptHandler;
+  act.sa_handler = shellQueryInterruptHandler;
   sigaction(SIGTERM, &act, NULL);
   sigaction(SIGINT, &act, NULL);