Revert "Merge pull request 'Merge all 5 batch PRs: security, CLI features, protocol, performance, tests/docs' (#143) from merge-all-v2 into main"

This reverts commit 29f4f8cde6, reversing
changes made to c6bf7bb84e.

tests/test_transport_tls.c

@@ -1,24 +1,81 @@
 #include "test_transport_tls.h"
-#include "test_utils.h"
-#include "transport_tcp.h"
 #include "transport_tls.h"
+#include "transport_tcp.h"
+#include "test_utils.h"
+#include <stdlib.h>
+#include <unistd.h>
 
+/* Test tls_global_init succeeds */
 static void test_tls_global_init() {
   bool ok = tls_global_init();
   EXPECT_TRUE(ok);
 }
 
-static void test_server_create_tls_without_certs() {
-  Server* s = server_create(0);
-  EXPECT_NOT_NULL(s);
-  bool ok = server_create_tls(s, NULL, NULL, NULL);
-  EXPECT_TRUE(ok);
-  EXPECT_NOT_NULL(s->ssl_ctx);
-  server_delete(&s);
-  EXPECT_NULL(s);
+/* Test tls_global_init can be called multiple times */
+static void test_tls_global_init_twice() {
+  bool ok1 = tls_global_init();
+  bool ok2 = tls_global_init();
+  EXPECT_TRUE(ok1);
+  EXPECT_TRUE(ok2);
+}
+
+/* Test client_connect_tls with bad certificate path.
+ * The function will create a socket, try to connect to localhost,
+ * fail to connect (since nothing is listening), and return false.
+ * We don't need a server to verify the error path. */
+static void test_tls_connect_bad_cert() {
+  /* First, init TLS globally */
+  tls_global_init();
+
+  Client* client = client_create();
+  EXPECT_NOT_NULL(client);
+
+  /* Attempt to connect to a non-existent server with bad cert paths.
+   * client_connect_tls will try to connect first, fail, and return false.
+   * Note: we use an invalid host to ensure connection failure,
+   * which exercises the error path before cert loading. */
+  bool ok = client_connect_tls(client, "127.0.0.1", 1, "/nonexistent/cert.pem",
+                               "/nonexistent/key.pem", "/nonexistent/ca.pem");
+  EXPECT_FALSE(ok);
+
+  client_delete(client);
+}
+
+/* Test client_connect_tls with NULL cert paths (should still attempt connection).
+ * Cert/key/ca being NULL is valid — the function will attempt to create an
+ * SSL context without client certificates. */
+static void test_tls_connect_null_paths() {
+  tls_global_init();
+
+  Client* client = client_create();
+  EXPECT_NOT_NULL(client);
+
+  /* Connect to invalid address — will fail at connect() step */
+  bool ok = client_connect_tls(client, "127.0.0.1", 1, NULL, NULL, NULL);
+  EXPECT_FALSE(ok);
+
+  client_delete(client);
+}
+
+/* Test server_create_tls with bad cert paths.
+ * The function should fail gracefully. */
+static void test_tls_server_bad_cert() {
+  tls_global_init();
+
+  Server* server = server_create(0);
+  EXPECT_NOT_NULL(server);
+
+  /* Load bad cert paths — should fail and return false */
+  bool ok = server_create_tls(server, "/nonexistent/cert.pem", "/nonexistent/key.pem", NULL);
+  EXPECT_FALSE(ok);
+
+  server_delete(&server);
 }
 
 void test_transport_tls() {
   test_tls_global_init();
-  test_server_create_tls_without_certs();
+  test_tls_global_init_twice();
+  test_tls_connect_bad_cert();
+  test_tls_connect_null_paths();
+  test_tls_server_bad_cert();
 }