Hotfix/sangshuduo/td 3197 fix taosdemo coverity scan (#8395)

* [TD-3197] <fix>: fix taosdemo coverity scan issues.

* [TD-3197] <fix>: fix taosdemo coverity scan issue.

fix subscribeTest pids uninitialized.

* [TD-3197] <fix>: fix taosdemo coverity scan issues.

* [TD-3197] <fix>: fix coverity scan issues.

check super tbl info pointer.

* [TD-3197] <fix>: fix coverity scan issues.

move sub tbl query thread join into loop

* [TD-3197] <fix>: fix coverity scan issues.

remove unused variable

* [TD-3197] <fix>: fix coverity scan issues.

use more secure random library

* [TD-3197] <fix>: fix coverity scan issues.

use strncpy for more safe

* [TD-3197] <fix>: fix taosdemo coverity scan issue.

replace arc4random with rand().

* [TD-3197] <fix>: fix coverity scan issues.

check stb info pointer for start time

* [TD-3197] <fix>: fix coverity scan issues.

fix strcpy vulnerability

* [TD-3197] <fix>: fix taosdemo coverity scan issue.

modify taosdemoTest2. try to check database continously.

* [TD-3197] <fix>: taosdemo coverity scan issues.

* [TD-3197] <fix>: fix memory leak when parsing arguments.

* [TD-3197] <fix>: fix cmake strip arguments.

* [TD-3197] <fix>: taosdemo coverity scan.

fix cmake string manipulation.

* [TD-3197]<fix>: taosdemo coverity scan issue.

configDir buffer overwrite.

* [TD-3197]<fix>: coverity scan issue.

taosdump argument validation.

* [TD-3197]<fix>: taosdemo and taosdump coverity scan issues.

* [TD-3197]<fix>: taosdemo coverity scan.

append result buf to file. for develop branch.

* exit if read sample file failed.

* fix converity scan issue.

* fix coverity scan issue.

* fix coverity scan memory leak.

* fix resource leak reported by coverity scan.

* fix taosdemo coverity scan issue.

* fix tcsetattr and getchar return value determination bug.

* fix coverity scan issue.

* fix two more coverity scan issues.

* fix stmt batch coverity scan issue.

* change to portable format.

* delete tests/examples/c/'-g' file

* fix example compile error.

* fix coverity scan issue

* fix taosdemo coverity scan issue.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

src/kit/taosdemo/taosdemo.c

@@ -3560,6 +3560,9 @@ static int postProceSql(char *host, uint16_t port,
             break;
         received += bytes;
 
+        response_buf[RESP_BUF_LEN - 1] = '\0';
+
+        if (strlen(response_buf)) {
             verbosePrint("%s() LN%d: received:%d resp_len:%d, response_buf:\n%s\n",
                     __func__, __LINE__, received, resp_len, response_buf);
 
@@ -3572,6 +3575,7 @@ static int postProceSql(char *host, uint16_t port,
                         __func__, __LINE__, received, resp_len, response_buf);
                 break;
             } 
+        }
     } while(received < resp_len);
 
     if (received == resp_len) {
@@ -3579,8 +3583,6 @@ static int postProceSql(char *host, uint16_t port,
         ERROR_EXIT("storing complete response from socket");
     }
 
-    response_buf[RESP_BUF_LEN - 1] = '\0';
-
     if (strlen(pThreadInfo->filePath) > 0) {
         appendResultBufToFile(response_buf, pThreadInfo);
     }