diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index f3706bcf..1f9764c4 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -159,7 +159,7 @@ add_library(session_fixture STATIC session_fixture.h session_fixture.c)
 target_link_libraries(session_fixture ${LIBRARIES} openssh_fixture libssh2)
 target_include_directories(session_fixture PRIVATE "${CMAKE_CURRENT_BINARY_DIR}")
 
-add_library(runner STATIC runner.c)
+add_library(runner STATIC runner.h runner.c)
 target_link_libraries(runner session_fixture)
 target_include_directories(runner PRIVATE "${CMAKE_CURRENT_BINARY_DIR}")
 
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 582c9141..0c01d911 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -55,6 +55,7 @@ EXTRA_DIST =                                                           \
  openssh_server/ssh_host_ed25519_key                                   \
  openssh_server/ssh_host_rsa_key                                       \
  runner.c                                                              \
+ runner.h                                                              \
  session_fixture.c                                                     \
  session_fixture.h                                                     \
  simple.c                                                              \
diff --git a/tests/openssh_fixture.c b/tests/openssh_fixture.c
index d4f7fd54..3a1588c2 100644
--- a/tests/openssh_fixture.c
+++ b/tests/openssh_fixture.c
@@ -216,7 +216,7 @@ static const char *docker_machine_name(void)
     return getenv("DOCKER_MACHINE_NAME");
 }
 
-static int is_running_inside_a_container()
+static int is_running_inside_a_container(void)
 {
 #ifdef WIN32
     return 0;
@@ -413,7 +413,7 @@ cleanup:
 
 static char *running_container_id = NULL;
 
-int start_openssh_fixture()
+int start_openssh_fixture(void)
 {
     int ret;
 #ifdef HAVE_WINSOCK2_H
@@ -438,7 +438,7 @@ int start_openssh_fixture()
     }
 }
 
-void stop_openssh_fixture()
+void stop_openssh_fixture(void)
 {
     if(running_container_id) {
         stop_openssh_server(running_container_id);
@@ -450,7 +450,7 @@ void stop_openssh_fixture()
     }
 }
 
-int open_socket_to_openssh_server()
+int open_socket_to_openssh_server(void)
 {
     return open_socket_to_container(running_container_id);
 }
diff --git a/tests/openssh_fixture.h b/tests/openssh_fixture.h
index 2d2bb0ad..f8e3632c 100644
--- a/tests/openssh_fixture.h
+++ b/tests/openssh_fixture.h
@@ -38,8 +38,8 @@
 #ifndef LIBSSH2_TESTS_OPENSSH_FIXTURE_H
 #define LIBSSH2_TESTS_OPENSSH_FIXTURE_H
 
-int start_openssh_fixture();
-void stop_openssh_fixture();
-int open_socket_to_openssh_server();
+int start_openssh_fixture(void);
+void stop_openssh_fixture(void);
+int open_socket_to_openssh_server(void);
 
 #endif
diff --git a/tests/runner.c b/tests/runner.c
index b9f9328d..f3522bba 100644
--- a/tests/runner.c
+++ b/tests/runner.c
@@ -36,10 +36,9 @@
  */
 
 #include "session_fixture.h"
+#include "runner.h"
 
-extern int test(LIBSSH2_SESSION *session);
-
-int main()
+int main(void)
 {
     int exit_code = 1;
     LIBSSH2_SESSION *session = start_session_fixture();
diff --git a/tests/runner.h b/tests/runner.h
new file mode 100644
index 00000000..f32a7af2
--- /dev/null
+++ b/tests/runner.h
@@ -0,0 +1,43 @@
+/* Copyright (C) 2016 Alexander Lamaison
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms,
+ * with or without modification, are permitted provided
+ * that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above
+ *   copyright notice, this list of conditions and the
+ *   following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials
+ *   provided with the distribution.
+ *
+ *   Neither the name of the copyright holder nor the names
+ *   of any other contributors may be used to endorse or
+ *   promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ */
+
+#ifndef LIBSSH2_TESTS_RUNNER_H
+#define LIBSSH2_TESTS_RUNNER_H
+
+int test(LIBSSH2_SESSION *session);
+
+#endif
diff --git a/tests/session_fixture.c b/tests/session_fixture.c
index 1f7e0f91..18df6624 100644
--- a/tests/session_fixture.c
+++ b/tests/session_fixture.c
@@ -61,7 +61,7 @@
 LIBSSH2_SESSION *connected_session = NULL;
 int connected_socket = -1;
 
-static int connect_to_server()
+static int connect_to_server(void)
 {
     int rc;
     connected_socket = open_socket_to_openssh_server();
@@ -78,7 +78,7 @@ static int connect_to_server()
     return 0;
 }
 
-void setup_fixture_workdir()
+static void setup_fixture_workdir(void)
 {
     char *wd = getenv("FIXTURE_WORKDIR");
 #ifdef FIXTURE_WORKDIR
@@ -99,7 +99,7 @@ void setup_fixture_workdir()
     chdir(wd);
 }
 
-LIBSSH2_SESSION *start_session_fixture()
+LIBSSH2_SESSION *start_session_fixture(void)
 {
     int rc;
 
@@ -146,7 +146,7 @@ void print_last_session_error(const char *function)
     }
 }
 
-void stop_session_fixture()
+void stop_session_fixture(void)
 {
     if(connected_session) {
         libssh2_session_disconnect(connected_session, "test ended");
diff --git a/tests/session_fixture.h b/tests/session_fixture.h
index d3824b79..bbb8e596 100644
--- a/tests/session_fixture.h
+++ b/tests/session_fixture.h
@@ -40,8 +40,8 @@
 
 #include <libssh2.h>
 
-LIBSSH2_SESSION *start_session_fixture();
-void stop_session_fixture();
+LIBSSH2_SESSION *start_session_fixture(void);
+void stop_session_fixture(void);
 void print_last_session_error(const char *function);
 
 #endif
diff --git a/tests/test_agent_forward_succeeds.c b/tests/test_agent_forward_succeeds.c
index daf7bd5a..569663b3 100644
--- a/tests/test_agent_forward_succeeds.c
+++ b/tests/test_agent_forward_succeeds.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_hostkey.c b/tests/test_hostkey.c
index e33f68f9..80588b00 100644
--- a/tests/test_hostkey.c
+++ b/tests/test_hostkey.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_hostkey_hash.c b/tests/test_hostkey_hash.c
index 112b491f..6f22d68f 100644
--- a/tests/test_hostkey_hash.c
+++ b/tests/test_hostkey_hash.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 #include "libssh2_config.h"
 
 #include <libssh2.h>
diff --git a/tests/test_keyboard_interactive_auth_fails_with_wrong_response.c b/tests/test_keyboard_interactive_auth_fails_with_wrong_response.c
index c1ab9730..f41d0ce6 100644
--- a/tests/test_keyboard_interactive_auth_fails_with_wrong_response.c
+++ b/tests/test_keyboard_interactive_auth_fails_with_wrong_response.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_keyboard_interactive_auth_info_request.c b/tests/test_keyboard_interactive_auth_info_request.c
index da6989d6..fc9e3d6a 100644
--- a/tests/test_keyboard_interactive_auth_info_request.c
+++ b/tests/test_keyboard_interactive_auth_info_request.c
@@ -46,27 +46,27 @@
 struct expected {
     int rc;
     int last_error_code;
-    char *last_error_message;
+    const char *last_error_message;
 };
 struct test_case {
-    char *data;
+    const char *data;
     int data_len;
     struct expected expected;
 };
 
 #define TEST_CASES_LEN 16
 struct test_case test_cases[TEST_CASES_LEN] = {
-    /* to small */
+    /* too small */
     {
         NULL, 0,
         {FAIL, -38,
         "userauth keyboard data buffer too small to get length"}},
-    /* to small */
+    /* too small */
     {
         "1234", 4,
         {FAIL, -38,
         "userauth keyboard data buffer too small to get length"}},
-    /* smalest valid packet possible */
+    /* smallest valid packet possible */
     {
         "<"
         "\0\0\0\0"
@@ -219,9 +219,8 @@ static int free_count = 0;
 static
 LIBSSH2_ALLOC_FUNC(test_alloc)
 {
-    alloc_count++;
-
     int *threshold_int_ptr = *abstract;
+    alloc_count++;
     if (*abstract != NULL && *threshold_int_ptr == alloc_count) {
         return NULL;
     }
@@ -241,12 +240,15 @@ LIBSSH2_FREE_FUNC(test_free)
 
 static
 int test_case(int num,
-              char *data, int data_len, void *abstract,
+              const char *data, int data_len, void *abstract,
               struct expected expected)
 {
+    int rc;
+    char *message;
+    int error_code;
+    LIBSSH2_SESSION *session = NULL;
     alloc_count = 0;
     free_count = 0;
-    LIBSSH2_SESSION *session = NULL;
     session = libssh2_session_init_ex(test_alloc, test_free, NULL, abstract);
     if(session == NULL) {
         fprintf(stderr, "libssh2_session_init_ex failed\n");
@@ -257,7 +259,7 @@ int test_case(int num,
     session->userauth_kybd_data_len = data_len;
     memcpy(session->userauth_kybd_data, data, data_len);
 
-    int rc = userauth_keyboard_interactive_decode_info_request(session);
+    rc = userauth_keyboard_interactive_decode_info_request(session);
 
     if(rc != expected.rc) {
         fprintf(stdout,
@@ -266,8 +268,7 @@ int test_case(int num,
         return 1;
     }
 
-    char *message;
-    int error_code = libssh2_session_last_error(session, &message, NULL, 0);
+    error_code = libssh2_session_last_error(session, &message, NULL, 0);
 
     if(expected.last_error_code != error_code) {
         fprintf(stdout,
@@ -291,7 +292,7 @@ int test_case(int num,
     return 0;
 }
 
-int main()
+int main(void)
 {
     int i;
 
@@ -332,4 +333,4 @@ bcrypt_pbkdf(const char *pass, size_t passlen, const uint8_t *salt,
 
     return -1;
 }
-#endif
\ No newline at end of file
+#endif
diff --git a/tests/test_keyboard_interactive_auth_succeeds_with_correct_response.c b/tests/test_keyboard_interactive_auth_succeeds_with_correct_response.c
index 093e4a22..224189ae 100644
--- a/tests/test_keyboard_interactive_auth_succeeds_with_correct_response.c
+++ b/tests/test_keyboard_interactive_auth_succeeds_with_correct_response.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_password_auth_fails_with_wrong_password.c b/tests/test_password_auth_fails_with_wrong_password.c
index 2b895d08..d888c78e 100644
--- a/tests/test_password_auth_fails_with_wrong_password.c
+++ b/tests/test_password_auth_fails_with_wrong_password.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_password_auth_fails_with_wrong_username.c b/tests/test_password_auth_fails_with_wrong_username.c
index b78617a4..e0630aa2 100644
--- a/tests/test_password_auth_fails_with_wrong_username.c
+++ b/tests/test_password_auth_fails_with_wrong_username.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_password_auth_succeeds_with_correct_credentials.c b/tests/test_password_auth_succeeds_with_correct_credentials.c
index 94b86b87..48e62373 100644
--- a/tests/test_password_auth_succeeds_with_correct_credentials.c
+++ b/tests/test_password_auth_succeeds_with_correct_credentials.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_fails_with_wrong_key.c b/tests/test_public_key_auth_fails_with_wrong_key.c
index dd2d254f..8b79edb6 100644
--- a/tests/test_public_key_auth_fails_with_wrong_key.c
+++ b/tests/test_public_key_auth_fails_with_wrong_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_dsa_key.c b/tests/test_public_key_auth_succeeds_with_correct_dsa_key.c
index 187c1313..c04d7682 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_dsa_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_dsa_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_ecdsa_key.c b/tests/test_public_key_auth_succeeds_with_correct_ecdsa_key.c
index 2ea3a369..febec6bb 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_ecdsa_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_ecdsa_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_ed25519_key.c b/tests/test_public_key_auth_succeeds_with_correct_ed25519_key.c
index c52830d9..0ef9cf50 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_ed25519_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_ed25519_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_ed25519_key_from_mem.c b/tests/test_public_key_auth_succeeds_with_correct_ed25519_key_from_mem.c
index a79d1b51..6553baeb 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_ed25519_key_from_mem.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_ed25519_key_from_mem.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_encrypted_ed25519_key.c b/tests/test_public_key_auth_succeeds_with_correct_encrypted_ed25519_key.c
index 553023a9..39e8cca5 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_encrypted_ed25519_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_encrypted_ed25519_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_encrypted_rsa_key.c b/tests/test_public_key_auth_succeeds_with_correct_encrypted_rsa_key.c
index ba98ac7c..35cb5048 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_encrypted_rsa_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_encrypted_rsa_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_rsa_key.c b/tests/test_public_key_auth_succeeds_with_correct_rsa_key.c
index 0cf2a633..40d9b80a 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_rsa_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_rsa_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_rsa_openssh_key.c b/tests/test_public_key_auth_succeeds_with_correct_rsa_openssh_key.c
index a067d729..22a9937f 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_rsa_openssh_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_rsa_openssh_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_signed_ecdsa_key.c b/tests/test_public_key_auth_succeeds_with_correct_signed_ecdsa_key.c
index 10b33cbb..398bfe38 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_signed_ecdsa_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_signed_ecdsa_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>
 
diff --git a/tests/test_public_key_auth_succeeds_with_correct_signed_rsa_key.c b/tests/test_public_key_auth_succeeds_with_correct_signed_rsa_key.c
index 39130e65..8843196f 100644
--- a/tests/test_public_key_auth_succeeds_with_correct_signed_rsa_key.c
+++ b/tests/test_public_key_auth_succeeds_with_correct_signed_rsa_key.c
@@ -1,4 +1,5 @@
 #include "session_fixture.h"
+#include "runner.h"
 
 #include <libssh2.h>