From 593ba012ac49065343f6bbf10adca5047414ce85 Mon Sep 17 00:00:00 2001
From: michael-grunder <michael.grunder@gmail.com>
Date: Sun, 4 May 2025 10:20:01 -0700
Subject: [PATCH] Check for `dragonfly_version` in `HELLO` response

DragonflyDB will report to be Redis but also include `dragonfly_version`
in the hello response, which we can use to identify the fork.

Also fix parsing of the `HELLO` response for `serverName()` and
`serverVersion()`. Starting in Redis 8.0 there seem to always be modules
running, which the previous function was not expecting or parsing.
---
 library.c           | 39 ++++++++++++++++++++++++++-------------
 redis.c             |  2 +-
 tests/RedisTest.php |  2 ++
 3 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/library.c b/library.c
index a9fb523e48..ce3e2672d0 100644
--- a/library.c
+++ b/library.c
@@ -2018,26 +2018,31 @@ static int
 redis_hello_response(INTERNAL_FUNCTION_PARAMETERS,
                      RedisSock *redis_sock, zval *z_tab, void *ctx)
 {
-    int numElems;
     zval z_ret, *zv;
+    int numElems;
 
-    if (read_mbulk_header(redis_sock, &numElems) < 0) {
-        if (IS_ATOMIC(redis_sock)) {
-            RETVAL_FALSE;
-        } else {
-            add_next_index_bool(z_tab, 0);
-        }
-        return FAILURE;
-    }
+    if (read_mbulk_header(redis_sock, &numElems) < 0)
+        goto fail;
 
     array_init(&z_ret);
-    redis_mbulk_reply_zipped_raw_variant(redis_sock, &z_ret, numElems);
+
+    if (redis_read_multibulk_recursive(redis_sock, numElems, 0, &z_ret) != SUCCESS ||
+        array_zip_values_recursive(&z_ret) != SUCCESS) 
+    {
+        zval_dtor(&z_ret);
+        goto fail;
+    }
 
     if (redis_sock->hello.server) {
         zend_string_release(redis_sock->hello.server);
     }
-    zv = zend_hash_str_find(Z_ARRVAL(z_ret), ZEND_STRL("server"));
-    redis_sock->hello.server = zv ? zval_get_string(zv) : ZSTR_EMPTY_ALLOC();
+
+    if ((zv = zend_hash_str_find(Z_ARRVAL(z_ret), ZEND_STRL("dragonfly_version")))) {
+        redis_sock->hello.server = zend_string_init(ZEND_STRL("dragonfly"), 0);
+    } else {
+        zv = zend_hash_str_find(Z_ARRVAL(z_ret), ZEND_STRL("server"));
+        redis_sock->hello.server = zv ? zval_get_string(zv) : ZSTR_EMPTY_ALLOC();
+    }
 
     if (redis_sock->hello.version) {
         zend_string_release(redis_sock->hello.version);
@@ -2063,6 +2068,14 @@ redis_hello_response(INTERNAL_FUNCTION_PARAMETERS,
     }
 
     return SUCCESS;
+
+fail:
+    if (IS_ATOMIC(redis_sock)) {
+        RETVAL_FALSE;
+    } else {
+        add_next_index_bool(z_tab, 0);
+    }
+    return FAILURE;
 }
 
 
@@ -4302,7 +4315,7 @@ redis_read_multibulk_recursive(RedisSock *redis_sock, long long elements, int st
         elements--;
     }
 
-    return 0;
+    return SUCCESS;
 }
 
 static int
diff --git a/redis.c b/redis.c
index 3f13a59888..629dd5c20b 100644
--- a/redis.c
+++ b/redis.c
@@ -2131,7 +2131,7 @@ redis_sock_read_multibulk_multi_reply_loop(INTERNAL_FUNCTION_PARAMETERS,
 
         int num = atol(inbuf + 1);
 
-        if (num > 0 && redis_read_multibulk_recursive(redis_sock, num, 0, &z_ret) < 0) {
+        if (num > 0 && redis_read_multibulk_recursive(redis_sock, num, 0, &z_ret) != SUCCESS) {
             return FAILURE;
         }
     }
diff --git a/tests/RedisTest.php b/tests/RedisTest.php
index e7854da442..1ebcc61e51 100644
--- a/tests/RedisTest.php
+++ b/tests/RedisTest.php
@@ -2476,6 +2476,7 @@ public function testServerInfo() {
             $this->markTestSkipped();
 
         $hello = $this->execHello();
+
         if ( ! $this->assertArrayKey($hello, 'server') ||
              ! $this->assertArrayKey($hello, 'version'))
         {
@@ -2486,6 +2487,7 @@ public function testServerInfo() {
         $this->assertEquals($hello['version'], $this->redis->serverVersion());
 
         $info = $this->redis->info();
+
         $cmd1 = $info['total_commands_processed'];
 
         /* Shouldn't hit the server */