From c2cbf6e42d2f96353206dba92fbdecce41645d8a Mon Sep 17 00:00:00 2001
From: Frago9876543210 <al.volf.av@gmail.com>
Date: Mon, 15 Jul 2019 22:46:05 +0300
Subject: [PATCH] Print symbol if error has occurred

---
 CMakeLists.txt           | 2 +-
 include/modloader/hook.h | 4 +++-
 src/hook.cpp             | 7 +++++++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37fa664..ae1f83d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -11,7 +11,7 @@ endif()
 
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
-set(MODLOADER_VERSION "Preview 1")
+set(MODLOADER_VERSION "Preview 2")
 
 add_subdirectory(dep/funchook)
 
diff --git a/include/modloader/hook.h b/include/modloader/hook.h
index 5dbffa8..e1cf6f9 100644
--- a/include/modloader/hook.h
+++ b/include/modloader/hook.h
@@ -9,6 +9,8 @@ extern "C" {
 
 typedef void modloader_hook_t;
 
+void* modloader_dlsym_print_error(const char *sym);
+
 modloader_hook_t* modloader_hook(void *sym, void *hook, void **orig);
 
 void modloader_destroy_hook(modloader_hook_t*);
@@ -48,7 +50,7 @@ class AutoHook {
     }
 
 
-    AutoHook(const char *sym, void *hook, void **orig) : AutoHook(dlsym(RTLD_DEFAULT, sym), hook, orig) {
+    AutoHook(const char *sym, void *hook, void **orig) : AutoHook(modloader_dlsym_print_error(sym), hook, orig) {
     }
 
     // workaround for a warning
diff --git a/src/hook.cpp b/src/hook.cpp
index 2992199..e08f77f 100644
--- a/src/hook.cpp
+++ b/src/hook.cpp
@@ -9,6 +9,13 @@ using namespace modloader;
 
 extern "C" {
 
+void *modloader_dlsym_print_error(const char *sym) {
+    void *ptr = dlsym(RTLD_DEFAULT, sym);
+    if (!ptr)
+        Log::error("Hook", "Unknown symbol %s", sym);
+    return ptr;
+}
+
 modloader_hook_t *modloader_hook(void *sym, void *hook, void **orig) {
     funchook_t *h = funchook_create();
     if (!h)