Small Fixes

libreborn/src/patch/instruction.cpp

@@ -1,50 +1,43 @@
 #include <libreborn/libreborn.h>
 #include "patch-internal.h"
 
+// Extract Target Address From B(L) Instruction
+static void *extract_from_bl_instruction(unsigned char *from, const uint32_t instruction) {
+    // Extract The Signed 24-Bit Immediate Value
+    int32_t imm24 = int32_t(instruction) & 0x00ffffff;
+    // Sign-Extend
+    if (imm24 & 0x00800000) {
+        imm24 |= int32_t(0xff000000);
+    }
+    // Calculate Offset
+    const int32_t offset = imm24 << 2;
+    // Compute Target Address
+    return from + 8 + offset;
+}
+void *extract_from_bl_instruction(unsigned char *from) {
+    return extract_from_bl_instruction(from, *(uint32_t *) from);
+}
+
 // Generate A BL Instruction
-#define INSTRUCTION_RANGE 32000000
-static uint64_t nice_diff_64(uint64_t a, uint64_t b) {
-    if (a > b) {
-        return a - b;
-    } else {
-        return b - a;
-    }
-}
-uint32_t generate_bl_instruction(void *from, void *to, int use_b_instruction) {
-    // Check Instruction Range
-    if (nice_diff_64((uint64_t) to, (uint64_t) from) > INSTRUCTION_RANGE) {
-        IMPOSSIBLE();
-    }
+uint32_t generate_bl_instruction(void *from, void *to, const int use_b_instruction) {
+    const uint32_t from_addr = uint32_t(from);
+    const uint32_t to_addr = uint32_t(to);
 
-    // Create New Instruction
-    uint32_t instruction;
-    unsigned char *instruction_array = (unsigned char *) &instruction;
-    instruction_array[3] = use_b_instruction ? B_INSTRUCTION : BL_INSTRUCTION;
+    // Calculate The Offset
+    const int32_t offset = int32_t((to_addr - from_addr - 8) >> 2); // Account For The 2-Bit Shift
 
-    // Determine PC
-    unsigned char *pc = ((unsigned char *) from) + 8;
-    int32_t offset = (int32_t) to - (int32_t) pc;
-    int32_t target = offset >> 2;
+    // Create the instruction
+    uint32_t instruction = use_b_instruction ? B_INSTRUCTION : BL_INSTRUCTION;
+    instruction *= 0x1000000;
 
-    // Set Instruction Offset
-    unsigned char *target_array = (unsigned char *) &target;
-    instruction_array[0] = target_array[0];
-    instruction_array[1] = target_array[1];
-    instruction_array[2] = target_array[2];
+    // Set The Offset (Last 24 Bits)
+    instruction |= (offset & 0x00FFFFFF);
+
+    // Check
+    if (to != extract_from_bl_instruction((unsigned char *) from, instruction)) {
+        ERR("Unable To Create Branch Instruction From %p To %p", from, to);
+    }
 
     // Return
     return instruction;
 }
-
-// Extract Target Address From B(L) Instruction
-void *extract_from_bl_instruction(unsigned char *from) {
-    // Calculate PC
-    unsigned char *pc = ((unsigned char *) from) + 8;
-
-    // Extract Offset From Instruction
-    int32_t target = *(int32_t *) from;
-    target = (target << 8) >> 8;
-    int32_t offset = target << 2;
-    // Add PC To Offset
-    return (void *) (pc + offset);
-}

media-layer/core/src/media.cpp

@@ -15,7 +15,7 @@
 // Allow Disabling Interaction
 static void update_cursor();
 static int is_interactable = 1;
-void media_set_interactable(int toggle) {
+void media_set_interactable(const int toggle) {
     if (bool(toggle) != is_interactable) {
         is_interactable = toggle;
         update_cursor();