MDEV-14974: --port ignored for --host=localhostbb-10.6-MDEV-1497410.6-MDEV-14974

Problem:
=======
MariaDB's command line utilities (e.g., mysql,
mysqldump, etc) silently ignore connection
property options (e.g., --port and --socket)
when protocol is not explicitly set via the
command-line for localhost connections.

Fix:
===
If connection properties are specified without a
protocol, override the protocol to be consistent.
For example, if --port is specified, automatically
set protocol=tcp.

Caveats:
=======
 * When multiple connection properties are
specified, nothing is overridden
 * If protocol is is set via the command-line,
its value is used

1 files changed, 66 insertions, 1 deletions

diff --git a/client/mysqlshow.c b/client/mysqlshow.c
index a89f4eb1dd2..d09839d04a8 100644
--- a/client/mysqlshow.c
+++ b/client/mysqlshow.c
@@ -41,6 +41,8 @@ static char *opt_plugin_dir= 0, *opt_default_auth= 0;
 
 static uint opt_protocol=0;
 
+static uint protocol_to_force= MYSQL_PROTOCOL_DEFAULT;
+
 static void get_options(int *argc,char ***argv);
 static uint opt_mysql_port=0;
 static int list_dbs(MYSQL *mysql,const char *wild);
@@ -70,11 +72,23 @@ int main(int argc, char **argv)
   static char **defaults_argv;
   MY_INIT(argv[0]);
   sf_leaking_memory=1; /* don't report memory leaks on early exits */
+
+  /* We need to know if protocol-related options originate from CLI args */
+  my_defaults_mark_files = TRUE;
+
   load_defaults_or_exit("my", load_default_groups, &argc, &argv);
   defaults_argv=argv;
 
   get_options(&argc,&argv);
 
+
+  /* Command line options override configured protocol */
+  if (protocol_to_force > MYSQL_PROTOCOL_DEFAULT
+      && protocol_to_force != opt_protocol)
+  {
+    warn_protocol_override(host, &opt_protocol, protocol_to_force);
+  }
+
   sf_leaking_memory=0; /* from now on we cleanup properly */
   wild=0;
   if (argc)
@@ -290,8 +304,12 @@ are shown.");
 
 static my_bool
 get_one_option(const struct my_option *opt, const char *argument,
-               const char *filename __attribute__((unused)))
+               const char *filename)
 {
+
+  /* Track when protocol is set via CLI to not force overrides */
+  static my_bool ignore_protocol_override = FALSE;
+
   switch(opt->id) {
   case 'v':
     opt_verbose++;
@@ -320,6 +338,13 @@ get_one_option(const struct my_option *opt, const char *argument,
   case 'W':
 #ifdef __WIN__
     opt_protocol = MYSQL_PROTOCOL_PIPE;
+
+    /* Prioritize pipe if explicit via command line */
+    if (filename[0] == '\0')
+    {
+      ignore_protocol_override = TRUE;
+      protocol_to_force = MYSQL_PROTOCOL_DEFAULT;
+    }
 #endif
     break;
   case OPT_MYSQL_PROTOCOL:
@@ -329,6 +354,46 @@ get_one_option(const struct my_option *opt, const char *argument,
       sf_leaking_memory= 1; /* no memory leak reports here */
       exit(1);
     }
+
+    /* Specification of protocol via CLI trumps implicit overrides */
+    if (filename[0] == '\0')
+    {
+      ignore_protocol_override = TRUE;
+      protocol_to_force = MYSQL_PROTOCOL_DEFAULT;
+    }
+
+    break;
+  case 'P':
+    /* If port and socket are set, fall back to default behavior */
+    if (protocol_to_force == SOCKET_PROTOCOL_TO_FORCE)
+    {
+      ignore_protocol_override = TRUE;
+      protocol_to_force = MYSQL_PROTOCOL_DEFAULT;
+    }
+
+    /* If port is set via CLI, try to force protocol to TCP */
+    if (filename[0] == '\0' &&
+        !ignore_protocol_override &&
+        protocol_to_force == MYSQL_PROTOCOL_DEFAULT)
+    {
+      protocol_to_force = MYSQL_PROTOCOL_TCP;
+    }
+    break;
+  case 'S':
+    /* If port and socket are set, fall back to default behavior */
+    if (protocol_to_force == MYSQL_PROTOCOL_TCP)
+    {
+      ignore_protocol_override = TRUE;
+      protocol_to_force = MYSQL_PROTOCOL_DEFAULT;
+    }
+
+    /* Prioritize socket if set via command line */
+    if (filename[0] == '\0' &&
+        !ignore_protocol_override &&
+        protocol_to_force == MYSQL_PROTOCOL_DEFAULT)
+    {
+      protocol_to_force = SOCKET_PROTOCOL_TO_FORCE;
+    }
     break;
   case '#':
     DBUG_PUSH(argument ? argument : "d:t:o");