From 7135bdf3825492f7d328b388c933bd2cd7811e7f Mon Sep 17 00:00:00 2001
From: apple1417 <git@apple1417.dev>
Date: Sat, 10 Aug 2024 13:27:36 +1200
Subject: [PATCH 1/4] allow specifying sigscan pattern offset inside hex string

got annoying counting bytes
---
 src/unrealsdk/game/bl2/globals.cpp | 20 ++++----
 src/unrealsdk/game/bl2/memory.cpp  |  7 ++-
 src/unrealsdk/game/bl3/globals.cpp | 28 +++++------
 src/unrealsdk/game/bl3/hooks.cpp   |  1 -
 src/unrealsdk/memory.h             | 78 +++++++++++++++++++-----------
 5 files changed, 76 insertions(+), 58 deletions(-)

diff --git a/src/unrealsdk/game/bl2/globals.cpp b/src/unrealsdk/game/bl2/globals.cpp
index b83c9dc..f490bb4 100644
--- a/src/unrealsdk/game/bl2/globals.cpp
+++ b/src/unrealsdk/game/bl2/globals.cpp
@@ -17,12 +17,11 @@ namespace {
 GObjects gobjects_wrapper{};
 
 const constinit Pattern<17> GOBJECTS_SIG{
-    "8B 0D ????????"  // mov ecx, [Borderlands2.exe+1682BD0]
-    "8B 04 ??"        // mov eax, [ecx+esi*4]
-    "8B 40 ??"        // mov eax, [eax+08]
-    "25 00020000"     // and eax, 00000200
-    ,
-    2};
+    "8B 0D {????????}"  // mov ecx, [Borderlands2.exe+1682BD0]
+    "8B 04 ??"          // mov eax, [ecx+esi*4]
+    "8B 40 ??"          // mov eax, [eax+08]
+    "25 00020000"       // and eax, 00000200
+};
 
 }  // namespace
 
@@ -42,11 +41,10 @@ namespace {
 GNames gnames_wrapper{};
 
 const constinit Pattern<10> GNAMES_SIG{
-    "A3 ????????"  // mov [BorderlandsPreSequel.exe+1520214], eax
-    "8B 45 ??"     // mov eax, [ebp+10]
-    "89 03"        // mov [ebx], eax
-    ,
-    1};
+    "A3 {????????}"  // mov [BorderlandsPreSequel.exe+1520214], eax
+    "8B 45 ??"       // mov eax, [ebp+10]
+    "89 03"          // mov [ebx], eax
+};
 
 }  // namespace
 
diff --git a/src/unrealsdk/game/bl2/memory.cpp b/src/unrealsdk/game/bl2/memory.cpp
index 70dba95..23becec 100644
--- a/src/unrealsdk/game/bl2/memory.cpp
+++ b/src/unrealsdk/game/bl2/memory.cpp
@@ -36,10 +36,9 @@ struct FMalloc {
 FMalloc* gmalloc;
 
 const constinit Pattern<8> GMALLOC_PATTERN{
-    "89 35 ????????"  // mov [Borderlands2.GDebugger+A95C], esi
-    "FF D7"           // call edi
-    ,
-    2};
+    "89 35 {????????}"  // mov [Borderlands2.GDebugger+A95C], esi
+    "FF D7"             // call edi
+};
 
 }  // namespace
 
diff --git a/src/unrealsdk/game/bl3/globals.cpp b/src/unrealsdk/game/bl3/globals.cpp
index 21969e9..b716e5d 100644
--- a/src/unrealsdk/game/bl3/globals.cpp
+++ b/src/unrealsdk/game/bl3/globals.cpp
@@ -17,12 +17,11 @@ namespace {
 GObjects gobjects_wrapper{};
 
 const constinit Pattern<26> GOBJECTS_SIG{
-    "48 8D 0D ????????"  // lea rcx, [Borderlands3.exe+69EBDA0]
-    "C6 05 ???????? 01"  // mov byte ptr [Borderlands3.exe+69EA290], 01
-    "E8 ????????"        // call Borderlands3.exe+17854D0
-    "C6 05 ???????? 01"  // mov byte ptr [Borderlands3.exe+64B78E0], 01
-    ,
-    3};
+    "48 8D 0D {????????}"  // lea rcx, [Borderlands3.exe+69EBDA0]
+    "C6 05 ???????? 01"    // mov byte ptr [Borderlands3.exe+69EA290], 01
+    "E8 ????????"          // call Borderlands3.exe+17854D0
+    "C6 05 ???????? 01"    // mov byte ptr [Borderlands3.exe+64B78E0], 01
+};
 
 }  // namespace
 
@@ -42,15 +41,14 @@ namespace {
 GNames gnames_wrapper{};
 
 const constinit Pattern<27> GNAMES_SIG{
-    "E8 ????????"        // call Borderlands3.exe+3DDBB7C
-    "48 8B C3"           // mov rax, rbx
-    "48 89 1D ????????"  // mov [Borderlands3.exe+69E71E8], rbx
-    "48 8B 5C 24 ??"     // mov rbx, [rsp+20]
-    "48 83 C4 28"        // add rsp, 28
-    "C3"                 // ret
-    "33 DB"              // xor ebx, ebx
-    ,
-    11};
+    "E8 ????????"          // call Borderlands3.exe+3DDBB7C
+    "48 8B C3"             // mov rax, rbx
+    "48 89 1D {????????}"  // mov [Borderlands3.exe+69E71E8], rbx
+    "48 8B 5C 24 ??"       // mov rbx, [rsp+20]
+    "48 83 C4 28"          // add rsp, 28
+    "C3"                   // ret
+    "33 DB"                // xor ebx, ebx
+};
 
 }  // namespace
 
diff --git a/src/unrealsdk/game/bl3/hooks.cpp b/src/unrealsdk/game/bl3/hooks.cpp
index be465ed..083608f 100644
--- a/src/unrealsdk/game/bl3/hooks.cpp
+++ b/src/unrealsdk/game/bl3/hooks.cpp
@@ -133,7 +133,6 @@ const constinit Pattern<20> CALL_FUNCTION_SIG{
     "41 56"              // push r14
     "41 57"              // push r15
     "48 81 EC 28010000"  // sub rsp, 00000128
-
 };
 
 }  // namespace
diff --git a/src/unrealsdk/memory.h b/src/unrealsdk/memory.h
index 047e2ad..c4ddb14 100644
--- a/src/unrealsdk/memory.h
+++ b/src/unrealsdk/memory.h
@@ -1,5 +1,5 @@
-#ifndef UNREALSDK_SIGSCAN_H
-#define UNREALSDK_SIGSCAN_H
+#ifndef UNREALSDK_MEMORY_H
+#define UNREALSDK_MEMORY_H
 
 #include "unrealsdk/pch.h"
 
@@ -107,10 +107,35 @@ struct Pattern {
         static_assert(sizeof(uint8_t) == sizeof(char), "uint8_t is different size to char");
     }
 
+   private:
+    /**
+     * @brief Converts a hex character to it's nibble and a mask.
+     *
+     * @param character The character.
+     * @return A pair of the nibble and it's mask.
+     */
+    consteval std::pair<uint8_t, uint8_t> char_to_nibble_and_mask(char character) {
+        // NOLINTBEGIN(readability-magic-numbers)
+        if ('0' <= character && character <= '9') {
+            return {(uint8_t)(character - '0'), (uint8_t)0xF};
+        }
+        if ('A' <= character && character <= 'F') {
+            return {(uint8_t)(character - 'A' + 0xA), (uint8_t)0xF};
+        }
+        if ('a' <= character && character <= 'f') {
+            return {(uint8_t)(character - 'a' + 0xA), (uint8_t)0xF};
+        }
+        return {(uint8_t)0, (uint8_t)0};
+        // NOLINTEND(readability-magic-numbers)
+    }
+
+   public:
     /**
      * @brief Constructs a pattern from a hex string, at compile time.
-     * @note Spaces are ignored, all other non hex characters get converted into a wildcard.
-     * @note The string must contain a whole number of bytes.
+     * @note An opening curly bracket sets the offset - only the first instance is used.
+     * @note Spaces and closing curly brackets are ignored.
+     * @note All other characters are considered wildcards.
+     * @note The string must contain a whole number of bytes. Nibble wildcards are allowed.
      *
      * @tparam m The size of the passed hex string - should be picked up automatically.
      * @param hex The hex string to convert.
@@ -118,7 +143,8 @@ struct Pattern {
      * @return A sigscan pattern.
      */
     template <size_t m>
-    consteval Pattern(const char (&hex)[m], ptrdiff_t offset = 0)
+    consteval Pattern(const char (&hex)[m],
+                      ptrdiff_t offset = std::numeric_limits<ptrdiff_t>::max())
         : bytes(), mask(), offset(offset) {
         size_t idx = 0;
         bool upper_nibble = true;
@@ -127,34 +153,28 @@ struct Pattern {
             if (character == '\0') {
                 break;
             }
-            if (character == ' ') {
+            if (character == ' ' || character == '}') {
                 continue;
             }
-
-            uint8_t byte = 0;
-            uint8_t mask_byte = 0;
-
-            // NOLINTBEGIN(readability-magic-numbers)
-            if ('0' <= character && character <= '9') {
-                byte = character - '0';
-                mask_byte = 0xF;
-            } else if ('A' <= character && character <= 'F') {
-                byte = character - 'A' + 0xA;
-                mask_byte = 0xF;
-            } else if ('a' <= character && character <= 'f') {
-                byte = character - 'a' + 0xA;
-                mask_byte = 0xF;
+            if (character == '{') {
+                if (!upper_nibble) {
+                    throw std::logic_error("Cannot start pattern offset halfway through a byte");
+                }
+                if (this->offset == std::numeric_limits<ptrdiff_t>::max()) {
+                    this->offset = idx;
+                }
+                continue;
             }
-            // NOLINTEND(readability-magic-numbers)
 
+            auto [nibble, nibble_mask] = char_to_nibble_and_mask(character);
             if (upper_nibble) {
-                this->bytes[idx] = byte << 4;
-                this->mask[idx] = mask_byte << 4;
+                this->bytes[idx] = nibble << 4;
+                this->mask[idx] = nibble_mask << 4;
 
                 upper_nibble = false;
             } else {
-                this->bytes[idx] |= byte;
-                this->mask[idx] |= mask_byte;
+                this->bytes[idx] |= nibble;
+                this->mask[idx] |= nibble_mask;
 
                 idx++;
                 upper_nibble = true;
@@ -164,7 +184,11 @@ struct Pattern {
         // Make sure we completely filled the pattern, there are no missing or extra bytes, and
         // we're not halfway through one.
         if (idx != n || !upper_nibble) {
-            throw "Invalid pattern size";
+            throw std::logic_error("Invalid pattern size");
+        }
+
+        if (this->offset == std::numeric_limits<ptrdiff_t>::max()) {
+            this->offset = 0;
         }
     }
 
@@ -196,4 +220,4 @@ struct Pattern {
 
 }  // namespace unrealsdk::memory
 
-#endif /* UNREALSDK_SIGSCAN_H */
+#endif /* UNREALSDK_MEMORY_H */

From b849b0e8a16a33bfe5d73a9c22308382521357d1 Mon Sep 17 00:00:00 2001
From: apple1417 <git@apple1417.dev>
Date: Sat, 10 Aug 2024 14:15:02 +1200
Subject: [PATCH 2/4] rework handling of failled sigscan errors

motivated by the bl3 mod menu breaking with no warnings or error messages, since it wasn't catching any errors
---
 src/unrealsdk/game/bl2/bl2.cpp      |  4 +--
 src/unrealsdk/game/bl2/globals.cpp  |  4 +--
 src/unrealsdk/game/bl2/hexedits.cpp |  6 ++--
 src/unrealsdk/game/bl2/hooks.cpp    |  4 +--
 src/unrealsdk/game/bl2/memory.cpp   |  4 ++-
 src/unrealsdk/game/bl2/object.cpp   |  8 ++---
 src/unrealsdk/game/bl3/bl3.cpp      |  6 ++--
 src/unrealsdk/game/bl3/globals.cpp  |  6 ++--
 src/unrealsdk/game/bl3/hooks.cpp    |  4 +--
 src/unrealsdk/game/bl3/memory.cpp   |  6 ++--
 src/unrealsdk/game/bl3/object.cpp   |  9 +++---
 src/unrealsdk/game/tps/hexedits.cpp |  2 +-
 src/unrealsdk/memory.cpp            |  9 ++++++
 src/unrealsdk/memory.h              | 49 +++++++++++++++++++++--------
 14 files changed, 79 insertions(+), 42 deletions(-)

diff --git a/src/unrealsdk/game/bl2/bl2.cpp b/src/unrealsdk/game/bl2/bl2.cpp
index 99e4348..38a5afb 100644
--- a/src/unrealsdk/game/bl2/bl2.cpp
+++ b/src/unrealsdk/game/bl2/bl2.cpp
@@ -64,7 +64,7 @@ const constinit Pattern<23> FNAME_INIT_SIG{
 }
 
 void BL2Hook::find_fname_init(void) {
-    this->fname_init_ptr = FNAME_INIT_SIG.sigscan<void*>();
+    this->fname_init_ptr = FNAME_INIT_SIG.sigscan_nullable<void*>();
     LOG(MISC, "FName::Init: {:p}", this->fname_init_ptr);
 }
 
@@ -96,7 +96,7 @@ const constinit Pattern<9> FFRAME_STEP_SIG{
 }  // namespace
 
 void BL2Hook::find_fframe_step(void) {
-    fframe_step_ptr = FFRAME_STEP_SIG.sigscan<fframe_step_func>();
+    fframe_step_ptr = FFRAME_STEP_SIG.sigscan_nullable<fframe_step_func>();
     LOG(MISC, "FFrame::Step: {:p}", reinterpret_cast<void*>(fframe_step_ptr));
 }
 void BL2Hook::fframe_step(FFrame* frame, UObject* obj, void* param) const {
diff --git a/src/unrealsdk/game/bl2/globals.cpp b/src/unrealsdk/game/bl2/globals.cpp
index f490bb4..076f863 100644
--- a/src/unrealsdk/game/bl2/globals.cpp
+++ b/src/unrealsdk/game/bl2/globals.cpp
@@ -26,7 +26,7 @@ const constinit Pattern<17> GOBJECTS_SIG{
 }  // namespace
 
 void BL2Hook::find_gobjects(void) {
-    auto gobjects_ptr = read_offset<GObjects::internal_type>(GOBJECTS_SIG.sigscan());
+    auto gobjects_ptr = read_offset<GObjects::internal_type>(GOBJECTS_SIG.sigscan_nullable());
     LOG(MISC, "GObjects: {:p}", reinterpret_cast<void*>(gobjects_ptr));
 
     gobjects_wrapper = GObjects(gobjects_ptr);
@@ -49,7 +49,7 @@ const constinit Pattern<10> GNAMES_SIG{
 }  // namespace
 
 void BL2Hook::find_gnames(void) {
-    auto gnames_ptr = read_offset<GNames::internal_type>(GNAMES_SIG.sigscan());
+    auto gnames_ptr = read_offset<GNames::internal_type>(GNAMES_SIG.sigscan_nullable());
     LOG(MISC, "GNames: {:p}", reinterpret_cast<void*>(gnames_ptr));
 
     gnames_wrapper = GNames(gnames_ptr);
diff --git a/src/unrealsdk/game/bl2/hexedits.cpp b/src/unrealsdk/game/bl2/hexedits.cpp
index 49e93b3..947970f 100644
--- a/src/unrealsdk/game/bl2/hexedits.cpp
+++ b/src/unrealsdk/game/bl2/hexedits.cpp
@@ -40,7 +40,7 @@ const constinit Pattern<15> ARRAY_LIMIT_MESSAGE{
 }  // namespace
 
 void BL2Hook::hexedit_set_command(void) {
-    auto set_command = SET_COMMAND_SIG.sigscan<uint8_t*>();
+    auto set_command = SET_COMMAND_SIG.sigscan_nullable<uint8_t*>();
     if (set_command == nullptr) {
         LOG(ERROR, "Couldn't find set command signature");
     } else {
@@ -55,7 +55,7 @@ void BL2Hook::hexedit_set_command(void) {
 }
 
 void BL2Hook::hexedit_array_limit(void) {
-    auto array_limit = ARRAY_LIMIT_SIG.sigscan<uint8_t*>();
+    auto array_limit = ARRAY_LIMIT_SIG.sigscan_nullable<uint8_t*>();
     if (array_limit == nullptr) {
         LOG(ERROR, "Couldn't find array limit signature");
     } else {
@@ -69,7 +69,7 @@ void BL2Hook::hexedit_array_limit(void) {
 }
 
 void BL2Hook::hexedit_array_limit_message(void) const {
-    auto array_limit_msg = ARRAY_LIMIT_MESSAGE.sigscan<uint8_t*>();
+    auto array_limit_msg = ARRAY_LIMIT_MESSAGE.sigscan_nullable<uint8_t*>();
     if (array_limit_msg == nullptr) {
         LOG(ERROR, "Couldn't find array limit message signature");
     } else {
diff --git a/src/unrealsdk/game/bl2/hooks.cpp b/src/unrealsdk/game/bl2/hooks.cpp
index 9db191d..04ec8ca 100644
--- a/src/unrealsdk/game/bl2/hooks.cpp
+++ b/src/unrealsdk/game/bl2/hooks.cpp
@@ -140,7 +140,7 @@ bool locking(void) {
 }  // namespace
 
 void BL2Hook::hook_process_event(void) {
-    detour(PROCESS_EVENT_SIG.sigscan(), locking() ? locking_process_event_hook : process_event_hook,
+    detour(PROCESS_EVENT_SIG, locking() ? locking_process_event_hook : process_event_hook,
            &process_event_ptr, "ProcessEvent");
 }
 
@@ -232,7 +232,7 @@ static_assert(std::is_same_v<decltype(&call_function_hook), call_function_func>,
 }  // namespace
 
 void BL2Hook::hook_call_function(void) {
-    detour(CALL_FUNCTION_SIG.sigscan(), call_function_hook, &call_function_ptr, "CallFunction");
+    detour(CALL_FUNCTION_SIG, call_function_hook, &call_function_ptr, "CallFunction");
 }
 
 }  // namespace unrealsdk::game
diff --git a/src/unrealsdk/game/bl2/memory.cpp b/src/unrealsdk/game/bl2/memory.cpp
index 23becec..14c2540 100644
--- a/src/unrealsdk/game/bl2/memory.cpp
+++ b/src/unrealsdk/game/bl2/memory.cpp
@@ -43,7 +43,9 @@ const constinit Pattern<8> GMALLOC_PATTERN{
 }  // namespace
 
 void BL2Hook::find_gmalloc(void) {
-    gmalloc = *read_offset<FMalloc**>(GMALLOC_PATTERN.sigscan());
+    // Using plain `sigscan` since there's an extra level of indirection here, want to make sure to
+    // print an error before we potentially dereference it
+    gmalloc = *read_offset<FMalloc**>(GMALLOC_PATTERN.sigscan("GMalloc"));
     LOG(MISC, "GMalloc: {:p}", reinterpret_cast<void*>(gmalloc));
 }
 void* BL2Hook::u_malloc(size_t len) const {
diff --git a/src/unrealsdk/game/bl2/object.cpp b/src/unrealsdk/game/bl2/object.cpp
index 18ebf71..397975e 100644
--- a/src/unrealsdk/game/bl2/object.cpp
+++ b/src/unrealsdk/game/bl2/object.cpp
@@ -56,7 +56,7 @@ const constinit Pattern<49> CONSTRUCT_OBJECT_PATTERN{
 }  // namespace
 
 void BL2Hook::find_construct_object(void) {
-    construct_obj_ptr = CONSTRUCT_OBJECT_PATTERN.sigscan<construct_obj_func>();
+    construct_obj_ptr = CONSTRUCT_OBJECT_PATTERN.sigscan_nullable<construct_obj_func>();
     LOG(MISC, "StaticConstructObject: {:p}", reinterpret_cast<void*>(construct_obj_ptr));
 }
 
@@ -106,7 +106,7 @@ const constinit Pattern<15> GET_PATH_NAME_PATTERN{
 };
 
 void BL2Hook::find_get_path_name(void) {
-    get_path_name_ptr = GET_PATH_NAME_PATTERN.sigscan<get_path_name_func>();
+    get_path_name_ptr = GET_PATH_NAME_PATTERN.sigscan_nullable<get_path_name_func>();
     LOG(MISC, "GetPathName: {:p}", reinterpret_cast<void*>(get_path_name_ptr));
 }
 
@@ -156,7 +156,7 @@ const constinit Pattern<56> STATIC_FIND_OBJECT_PATTERN{
 }  // namespace
 
 void BL2Hook::find_static_find_object(void) {
-    static_find_object_ptr = STATIC_FIND_OBJECT_PATTERN.sigscan<static_find_object_func>();
+    static_find_object_ptr = STATIC_FIND_OBJECT_PATTERN.sigscan_nullable<static_find_object_func>();
     LOG(MISC, "StaticFindObject: {:p}", reinterpret_cast<void*>(static_find_object_ptr));
 }
 
@@ -196,7 +196,7 @@ const constinit Pattern<46> LOAD_PACKAGE_PATTERN{
 }  // namespace
 
 void BL2Hook::find_load_package(void) {
-    load_package_ptr = LOAD_PACKAGE_PATTERN.sigscan<load_package_func>();
+    load_package_ptr = LOAD_PACKAGE_PATTERN.sigscan_nullable<load_package_func>();
     LOG(MISC, "LoadPackage: {:p}", reinterpret_cast<void*>(load_package_ptr));
 }
 
diff --git a/src/unrealsdk/game/bl3/bl3.cpp b/src/unrealsdk/game/bl3/bl3.cpp
index 3efd0b1..52615fa 100644
--- a/src/unrealsdk/game/bl3/bl3.cpp
+++ b/src/unrealsdk/game/bl3/bl3.cpp
@@ -57,7 +57,7 @@ const constinit Pattern<15> FNAME_INIT_PATTERN{
 }  // namespace
 
 void BL3Hook::find_fname_init(void) {
-    fname_init_ptr = FNAME_INIT_PATTERN.sigscan<fname_init_func>();
+    fname_init_ptr = FNAME_INIT_PATTERN.sigscan_nullable<fname_init_func>();
     LOG(MISC, "FName::Init: {:p}", reinterpret_cast<void*>(fname_init_ptr));
 }
 
@@ -83,7 +83,7 @@ const constinit Pattern<10> FFRAME_STEP_SIG{
 }  // namespace
 
 void BL3Hook::find_fframe_step(void) {
-    fframe_step_ptr = FFRAME_STEP_SIG.sigscan<fframe_step_func>();
+    fframe_step_ptr = FFRAME_STEP_SIG.sigscan_nullable<fframe_step_func>();
     LOG(MISC, "FFrame::Step: {:p}", reinterpret_cast<void*>(fframe_step_ptr));
 }
 void BL3Hook::fframe_step(FFrame* frame, UObject* obj, void* param) const {
@@ -145,7 +145,7 @@ const constinit Pattern<131> FTEXT_AS_CULTURE_INVARIANT_PATTERN{
 
 void BL3Hook::find_ftext_as_culture_invariant(void) {
     ftext_as_culture_invariant_ptr =
-        FTEXT_AS_CULTURE_INVARIANT_PATTERN.sigscan<ftext_as_culture_invariant_func>();
+        FTEXT_AS_CULTURE_INVARIANT_PATTERN.sigscan_nullable<ftext_as_culture_invariant_func>();
     LOG(MISC, "FText::AsCultureInvariant: {:p}", reinterpret_cast<void*>(fname_init_ptr));
 }
 
diff --git a/src/unrealsdk/game/bl3/globals.cpp b/src/unrealsdk/game/bl3/globals.cpp
index b716e5d..4491a73 100644
--- a/src/unrealsdk/game/bl3/globals.cpp
+++ b/src/unrealsdk/game/bl3/globals.cpp
@@ -26,7 +26,7 @@ const constinit Pattern<26> GOBJECTS_SIG{
 }  // namespace
 
 void BL3Hook::find_gobjects(void) {
-    auto gobjects_ptr = read_offset<GObjects::internal_type>(GOBJECTS_SIG.sigscan());
+    auto gobjects_ptr = read_offset<GObjects::internal_type>(GOBJECTS_SIG.sigscan_nullable());
     LOG(MISC, "GObjects: {:p}", reinterpret_cast<void*>(gobjects_ptr));
 
     gobjects_wrapper = GObjects(gobjects_ptr);
@@ -53,7 +53,9 @@ const constinit Pattern<27> GNAMES_SIG{
 }  // namespace
 
 void BL3Hook::find_gnames(void) {
-    auto gnames_ptr = *read_offset<GNames::internal_type*>(GNAMES_SIG.sigscan());
+    // Using plain `sigscan` since there's an extra level of indirection here, want to make sure to
+    // print an error before we potentially dereference it
+    auto gnames_ptr = *read_offset<GNames::internal_type*>(GNAMES_SIG.sigscan("GNames"));
     LOG(MISC, "GNames: {:p}", reinterpret_cast<void*>(gnames_ptr));
 
     gnames_wrapper = GNames(gnames_ptr);
diff --git a/src/unrealsdk/game/bl3/hooks.cpp b/src/unrealsdk/game/bl3/hooks.cpp
index 083608f..b30709f 100644
--- a/src/unrealsdk/game/bl3/hooks.cpp
+++ b/src/unrealsdk/game/bl3/hooks.cpp
@@ -105,7 +105,7 @@ bool locking(void) {
 }
 
 void BL3Hook::hook_process_event(void) {
-    detour(PROCESS_EVENT_SIG.sigscan(), locking() ? locking_process_event_hook : process_event_hook,
+    detour(PROCESS_EVENT_SIG, locking() ? locking_process_event_hook : process_event_hook,
            &process_event_ptr, "ProcessEvent");
 }
 
@@ -213,7 +213,7 @@ static_assert(std::is_same_v<decltype(call_function_hook), call_function_func>,
               "call_function signature is incorrect");
 
 void BL3Hook::hook_call_function(void) {
-    detour(CALL_FUNCTION_SIG.sigscan(), call_function_hook, &call_function_ptr, "CallFunction");
+    detour(CALL_FUNCTION_SIG, call_function_hook, &call_function_ptr, "CallFunction");
 }
 
 }  // namespace unrealsdk::game
diff --git a/src/unrealsdk/game/bl3/memory.cpp b/src/unrealsdk/game/bl3/memory.cpp
index 207d8f4..6b7f1a0 100644
--- a/src/unrealsdk/game/bl3/memory.cpp
+++ b/src/unrealsdk/game/bl3/memory.cpp
@@ -53,9 +53,9 @@ const constinit Pattern<20> FREE_PATTERN{
 }  // namespace
 
 void BL3Hook::find_gmalloc(void) {
-    fmemory_malloc_ptr = MALLOC_PATTERN.sigscan<fmemory_malloc_func>();
-    fmemory_realloc_ptr = REALLOC_PATTERN.sigscan<fmemory_realloc_func>();
-    fmemory_free_ptr = FREE_PATTERN.sigscan<fmemory_free_func>();
+    fmemory_malloc_ptr = MALLOC_PATTERN.sigscan_nullable<fmemory_malloc_func>();
+    fmemory_realloc_ptr = REALLOC_PATTERN.sigscan_nullable<fmemory_realloc_func>();
+    fmemory_free_ptr = FREE_PATTERN.sigscan_nullable<fmemory_free_func>();
 
     LOG(MISC, "FMemory::Malloc: {:p}", reinterpret_cast<void*>(fmemory_malloc_ptr));
     LOG(MISC, "FMemory::Realloc: {:p}", reinterpret_cast<void*>(fmemory_realloc_ptr));
diff --git a/src/unrealsdk/game/bl3/object.cpp b/src/unrealsdk/game/bl3/object.cpp
index eca6a0a..30348f9 100644
--- a/src/unrealsdk/game/bl3/object.cpp
+++ b/src/unrealsdk/game/bl3/object.cpp
@@ -48,7 +48,7 @@ const constinit Pattern<55> CONSTRUCT_OBJECT_PATTERN{
 }  // namespace
 
 void BL3Hook::find_construct_object(void) {
-    construct_obj_ptr = CONSTRUCT_OBJECT_PATTERN.sigscan<construct_obj_func>();
+    construct_obj_ptr = CONSTRUCT_OBJECT_PATTERN.sigscan_nullable<construct_obj_func>();
     LOG(MISC, "StaticConstructObject: {:p}", reinterpret_cast<void*>(construct_obj_ptr));
 }
 
@@ -84,7 +84,7 @@ const constinit Pattern<21> GET_PATH_NAME_PATTERN{
 }  // namespace
 
 void BL3Hook::find_get_path_name(void) {
-    get_path_name_ptr = GET_PATH_NAME_PATTERN.sigscan<get_path_name_func>();
+    get_path_name_ptr = GET_PATH_NAME_PATTERN.sigscan_nullable<get_path_name_func>();
     LOG(MISC, "GetPathName: {:p}", reinterpret_cast<void*>(get_path_name_ptr));
 }
 
@@ -120,7 +120,8 @@ const constexpr intptr_t ANY_PACKAGE = -1;
 }  // namespace
 
 void BL3Hook::find_static_find_object(void) {
-    static_find_object_ptr = STATIC_FIND_OBJECT_PATTERN.sigscan<static_find_object_safe_func>();
+    static_find_object_ptr =
+        STATIC_FIND_OBJECT_PATTERN.sigscan_nullable<static_find_object_safe_func>();
     LOG(MISC, "StaticFindObjectSafe: {:p}", reinterpret_cast<void*>(static_find_object_ptr));
 }
 
@@ -152,7 +153,7 @@ const constinit Pattern<16> LOAD_PACKAGE_PATTERN{
 }  // namespace
 
 void BL3Hook::find_load_package(void) {
-    load_package_ptr = LOAD_PACKAGE_PATTERN.sigscan<load_package_func>();
+    load_package_ptr = LOAD_PACKAGE_PATTERN.sigscan_nullable<load_package_func>();
     LOG(MISC, "LoadPackage: {:p}", reinterpret_cast<void*>(load_package_ptr));
 }
 
diff --git a/src/unrealsdk/game/tps/hexedits.cpp b/src/unrealsdk/game/tps/hexedits.cpp
index 44ec421..c8f658f 100644
--- a/src/unrealsdk/game/tps/hexedits.cpp
+++ b/src/unrealsdk/game/tps/hexedits.cpp
@@ -20,7 +20,7 @@ const constinit Pattern<11> ARRAY_LIMIT_MESSAGE{
 }  // namespace
 
 void TPSHook::hexedit_array_limit_message(void) const {
-    auto array_limit_msg = ARRAY_LIMIT_MESSAGE.sigscan<uint8_t*>();
+    auto array_limit_msg = ARRAY_LIMIT_MESSAGE.sigscan_nullable<uint8_t*>();
     if (array_limit_msg == nullptr) {
         LOG(ERROR, "Couldn't find array limit message signature");
     } else {
diff --git a/src/unrealsdk/memory.cpp b/src/unrealsdk/memory.cpp
index 9f05fa2..38493fb 100644
--- a/src/unrealsdk/memory.cpp
+++ b/src/unrealsdk/memory.cpp
@@ -84,6 +84,11 @@ bool detour(uintptr_t addr, void* detour_func, void** original_func, std::string
 }
 #else
 bool detour(uintptr_t addr, void* detour_func, void** original_func, std::string_view name) {
+    if (addr == 0) {
+        LOG(ERROR, "Detour for {} was passed a null address!", name);
+        return false;
+    }
+
     MH_STATUS status = MH_OK;
 
     status = MH_CreateHook(reinterpret_cast<LPVOID>(addr), detour_func, original_func);
@@ -114,6 +119,10 @@ UNREALSDK_CAPI(bool,
 #endif
 
 uintptr_t read_offset(uintptr_t address) {
+    if (address == 0) {
+        LOG(ERROR, "Attempted to read a null offset!");
+        return 0;
+    }
 #ifdef ARCH_X64
     return address + *reinterpret_cast<int32_t*>(address) + 4;
 #else
diff --git a/src/unrealsdk/memory.h b/src/unrealsdk/memory.h
index c4ddb14..2dbac55 100644
--- a/src/unrealsdk/memory.h
+++ b/src/unrealsdk/memory.h
@@ -5,6 +5,9 @@
 
 namespace unrealsdk::memory {
 
+template <size_t n>
+struct Pattern;
+
 /**
  * @brief Performs a sigscan.
  *
@@ -39,7 +42,9 @@ T sigscan(const uint8_t* bytes,
  * @brief Detours a function.
  *
  * @tparam T The signature of the detour'd function (should be picked up automatically).
+ * @tparam n The size of the sigscan pattern (should be picked up automatically).
  * @param addr The address of the function.
+ * @param pattern A sigscan pattern matching the function to detour.
  * @param detour_func The detour function.
  * @param original_func Pointer to store the original function.
  * @param name Name of the detour, to be used in log messages on error.
@@ -51,6 +56,19 @@ bool detour(uintptr_t addr, T detour_func, T* original_func, std::string_view na
     return detour(addr, reinterpret_cast<void*>(detour_func),
                   reinterpret_cast<void**>(original_func), name);
 }
+template <size_t n>
+bool detour(const Pattern<n>& pattern,
+            void* detour_func,
+            void** original_func,
+            std::string_view name) {
+    // Use sigscan nullable since the base detour function will warn about a null address
+    return detour(pattern.sigscan_nullable(), detour_func, original_func, name);
+}
+template <typename T, size_t n>
+bool detour(const Pattern<n>& pattern, T detour_func, T* original_func, std::string_view name) {
+    return detour(pattern.sigscan_nullable(), reinterpret_cast<void*>(detour_func),
+                  reinterpret_cast<void**>(original_func), name);
+}
 
 /**
  * @brief Reads an assembly offset, and gets the address it points to.
@@ -193,28 +211,33 @@ struct Pattern {
     }
 
     /**
-     * @brief Performs a sigscan for this pattern.
+     * @brief Performs a sigscan for this pattern across the main executable.
+     * @note When not found, `sigscan` throws, while `sigscan_nullable` returns 0.
      *
      * @tparam T The type to cast the result to.
-     * @param start The address to start the search at. Defaults to the start of the exe.
-     * @param size The length of the region to search. Defaults to the exe size
-     * @return The found location, or nullptr.
+     * @param name The name of this pattern, to use in error messages.
+     * @return The found location, or 0.
      */
-    [[nodiscard]] uintptr_t sigscan(void) const {
+    [[nodiscard]] uintptr_t sigscan(std::string_view name) const {
         auto addr = memory::sigscan(this->bytes.data(), this->mask.data(), n);
-        return addr == 0 ? 0 : addr + offset;
-    }
-    [[nodiscard]] uintptr_t sigscan(uintptr_t start, size_t size) const {
-        auto addr = memory::sigscan(this->bytes.data(), this->mask.data(), n, start, size);
+        if (addr == 0) {
+            // Make sure to log something on error, even if calling code doesn't catch it
+            LOG(ERROR, "Sigscan for {} failed!", name);
+            throw std::runtime_error("sigscan failed");
+        }
         return addr == 0 ? 0 : addr + offset;
     }
     template <typename T>
-    [[nodiscard]] T sigscan(void) const {
-        return reinterpret_cast<T>(this->sigscan());
+    [[nodiscard]] T sigscan(std::string_view name) const {
+        return reinterpret_cast<T>(this->sigscan(name));
+    }
+    [[nodiscard]] uintptr_t sigscan_nullable(void) const {
+        auto addr = memory::sigscan(this->bytes.data(), this->mask.data(), n);
+        return addr == 0 ? 0 : addr + offset;
     }
     template <typename T>
-    [[nodiscard]] T sigscan(uintptr_t start, size_t size) const {
-        return reinterpret_cast<T>(this->sigscan(start, size));
+    [[nodiscard]] T sigscan_nullable(void) const {
+        return reinterpret_cast<T>(this->sigscan_nullable());
     }
 };
 

From 16c9d2d28b488b4ec0abf641dc7d3e40c303d15f Mon Sep 17 00:00:00 2001
From: apple1417 <git@apple1417.dev>
Date: Sat, 10 Aug 2024 14:57:37 +1200
Subject: [PATCH 3/4] update libraries

---
 common_cmake | 2 +-
 libs/fmt     | 2 +-
 libs/minhook | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/common_cmake b/common_cmake
index c953298..e1d46e3 160000
--- a/common_cmake
+++ b/common_cmake
@@ -1 +1 @@
-Subproject commit c95329887138e361a46b1129b640c77f00df7086
+Subproject commit e1d46e3bc526f5a53ca08fb5592f3b7fb6f37349
diff --git a/libs/fmt b/libs/fmt
index f5e5435..0c9fce2 160000
--- a/libs/fmt
+++ b/libs/fmt
@@ -1 +1 @@
-Subproject commit f5e54359df4c26b6230fc61d38aa294581393084
+Subproject commit 0c9fce2ffefecfdce794e1859584e25877b7b592
diff --git a/libs/minhook b/libs/minhook
index 0f25a24..c1a7c38 160000
--- a/libs/minhook
+++ b/libs/minhook
@@ -1 +1 @@
-Subproject commit 0f25a2449b3cf878bcbdbf91b693c38149ecf029
+Subproject commit c1a7c3843bd1a5fe3eb779b64c0d823bca3dc339

From 979b2fcca73c935b271a64bcd8a46c335850cc0e Mon Sep 17 00:00:00 2001
From: apple1417 <git@apple1417.dev>
Date: Sat, 10 Aug 2024 15:13:54 +1200
Subject: [PATCH 4/4] update changelog

---
 changelog.md | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/changelog.md b/changelog.md
index 2183c23..9b23880 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,6 +1,6 @@
 # Changelog
 
-## v1.2.0 (Upcoming)
+## v1.2.0
 - When an exception occurs during a hook, now mention what function it was under, to make debugging
   easier.
 
@@ -59,6 +59,13 @@
   [91e3fcd5](https://github.com/bl-sdk/unrealsdk/commit/91e3fcd5),
   [8ec285fc](https://github.com/bl-sdk/unrealsdk/commit/8ec285fc)
 
+- Tweaked `Pattern::sigscan` to more explicitly deal with sigscans failing. Existing code will have
+  to be updated to either call `sigscan_nullable` (if failing is ok), or to pass a name to use in
+  case of error (if throwing is ok).
+
+  [7135bdf3](https://github.com/bl-sdk/unrealsdk/commit/7135bdf3),
+  [b849b0e8](https://github.com/bl-sdk/unrealsdk/commit/91e3fcd5)
+
 - Made the `UnrealPointer` constructor explicit.
 
   [26a47713](https://github.com/bl-sdk/unrealsdk/commit/26a47713)