From cc5576476adaea4ae6a10c61d0c3aafdabe45fa1 Mon Sep 17 00:00:00 2001
From: Donat Zenichev <dzenichev@sipwise.com>
Date: Mon, 1 Jun 2026 17:30:40 +0200
Subject: [PATCH] MT#61856 control_ng: add func for command lookup

Instead of the previous approach using the strhash,
introduce if-based lookup from `NG_COMMANDS`.

The usage of strhash is deprecated because it:
- forses string literals in switch cases, hence gives
  no possibility to use variables
- makes then shortcuts using macro not possible to be used
- it makes the part with the command find and
  actual commands definition duplicate, because
  one has to maintain both of them when adding/removing commands
- switch is redundant and feels heavy, meanwhile the same
  thing can be generated using marco based on `NG_COMMANDS`
  introduced before, which are the main source of the truth

Newer approach:
- avoid usage of for/while cycles (because CPU consuming)
- sorts the lookup based on the cmd name (string) length,
  what makes the command find efficient, because exlcludes
  unnecessary comparisons
- uses the `memcmp()` at the very last
- for example, for the "offer" command it may run the `memcmp()`
  only two times, because there are only two commands with
  the length 5 our of supported 35 commands in list now

Additionally:
include `string.h` for `memcmp()` operations.

Change-Id: Iae70de87b88cd444ae162ba2b7c6aa7690731ee3
---
 daemon/control_ng.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/daemon/control_ng.c b/daemon/control_ng.c
index a28975515..c62cf87d8 100644
--- a/daemon/control_ng.c
+++ b/daemon/control_ng.c
@@ -16,6 +16,7 @@
 #include "statistics.h"
 #include "streambuf.h"
 #include "homer.h"
+#include <string.h>
 
 mutex_t rtpe_cngs_lock;
 mutex_t tcp_connections_lock;
@@ -55,6 +56,26 @@ static const struct ng_command_def ng_command_defs[OP_COUNT] = {
 #undef X
 };
 
+static const struct ng_command_def *ng_command_find(const str *cmd) {
+	if (!cmd || !cmd->s)
+		return NULL;
+
+#define X(op, name, esc, short_name, handler) \
+	if (cmd->len == sizeof(name) - 1 && !memcmp(cmd->s, name, sizeof(name) - 1)) \
+		return &ng_command_defs[op];
+
+#define XA(op, name, esc, short_name, handler) \
+	if (cmd->len == sizeof(name) - 1 && !memcmp(cmd->s, name, sizeof(name) - 1)) \
+		return &ng_command_defs[op];
+
+	NG_COMMANDS(X, XA)
+
+#undef XA
+#undef X
+
+	return NULL;
+}
+
 const char *ng_command_strings[OP_COUNT] = {
 #define X(op, name, esc, short_name, handler) [op] = name,
 #define XA(op, name, esc, short_name, handler) [op] = name,