[mod_pgsql] Fix potential hang when calling PQconsumeInput() while checking if db_is_...

diff --git a/src/mod/databases/mod_pgsql/mod_pgsql.c b/src/mod/databases/mod_pgsql/mod_pgsql.c
index a534594548e281831ba8f03a812176aca4c2a109..b94b1abc7338519d69df47190805a909d76ec0dd 100644 (file)
--- a/src/mod/databases/mod_pgsql/mod_pgsql.c
+++ b/src/mod/databases/mod_pgsql/mod_pgsql.c
@@ -113,6 +113,7 @@ static int db_is_up(switch_pgsql_handle_t *handle)
        int max_tries = DEFAULT_PGSQL_RETRIES;
        int code = 0;
        int recon = 0;
+       switch_byte_t sanity = 255;
 
        if (handle) {
                max_tries = handle->num_retries;
@@ -132,10 +133,24 @@ top:
        }
 
        /* Try a non-blocking read on the connection to gobble up any EOF from a closed connection and mark the connection BAD if it is closed. */
-       PQconsumeInput(handle->con);
+       while (--sanity > 0)
+       {
+               if (PQisBusy(handle->con)) {
+                       PQconsumeInput(handle->con);
+                       switch_yield(1);
+                       continue;
+               }
+               break;
+       }
+
+       if (!sanity) {
+               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_CRIT, "Can not check DB Connection status: sanity = 0. Reconnecting...\n");
+               goto reset;
+       }
 
        if (PQstatus(handle->con) == CONNECTION_BAD) {
                switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "PQstatus returned bad connection; reconnecting...\n");
+reset:
                handle->state = SWITCH_PGSQL_STATE_ERROR;
                PQreset(handle->con);
                if (PQstatus(handle->con) == CONNECTION_BAD) {
@@ -486,15 +501,13 @@ error:
        err_str = pgsql_handle_get_error(handle);
 
        if (zstr(err_str)) {
-               if (zstr(er)) {
+               if (!er) {
                        err_str = strdup((char *)"SQL ERROR!");
                } else {
                        err_str = er;
                }
        } else {
-               if (!zstr(er)) {
-                       free(er);
-               }
+               switch_safe_free(er);
        }
 
        if (err_str) {