Correct handle the value return from mgmt socket read and write (apache#6220)

Author: oknet

mgmt/utils/MgmtUtils.cc

@@ -70,11 +70,7 @@ mgmt_readline(int soc, char *buf, int maxlen)
         break;
       }
     } else if (rc == 0) {
-      if (n == 1) { /* EOF */
-        return 0;
-      } else {
-        break;
-      }
+      return n;
     } else { /* Error */
       if (errno == ECONNRESET || errno == EPIPE) {
         return n ? n : 0;
@@ -112,7 +108,7 @@ mgmt_writeline(int soc, const char *data, int nbytes)
   while (nleft > 0) {
     int nwritten = write_socket(soc, tmp, nleft);
     if (nwritten <= 0) { /* Error or nothing written */
-      return nwritten;
+      return nleft;
     }
     nleft -= nwritten;
     tmp += nwritten;
@@ -147,7 +143,7 @@ mgmt_read_pipe(int fd, char *buf, int bytes_to_read)
   while (bytes_to_read > 0) {
     int err = read_socket(fd, p, bytes_to_read);
     if (err == 0) {
-      return err;
+      return bytes_read;
     } else if (err < 0) {
       // Turn ECONNRESET into EOF.
       if (errno == ECONNRESET || errno == EPIPE) {
@@ -188,7 +184,7 @@ mgmt_write_pipe(int fd, char *buf, int bytes_to_write)
   while (bytes_to_write > 0) {
     int err = write_socket(fd, p, bytes_to_write);
     if (err == 0) {
-      return err;
+      return bytes_written;
     } else if (err < 0) {
       if (mgmt_transient_error()) {
         mgmt_sleep_msec(1);