chore: split up some structs and add comments

src/aout.rs

@@ -1,3 +1,5 @@
+//! Internal a.out File abstraction.
+
 use std::ffi::{c_uchar, c_ushort};
 
 #[allow(non_camel_case_types)]

src/disasm.rs

@@ -1,14 +1,15 @@
-use core::fmt;
-use std::{fs::File, io::Read, process::exit};
+//! The main dissembling logic.
 
 use crate::aout::Aout;
-use crate::instructions::{Displacement, IByte, IWord, MemoryIndex, ModRmTarget, Operand, Pointer};
+use crate::operands::{Displacement, IByte, IWord, MemoryIndex, ModRmTarget, Operand, Pointer};
 use crate::register::{Register, RegisterId, SegmentRegister};
 use crate::{
     Args,
     instructions::{Instruction, Mnemonic},
 };
 use crate::{modrmb, modrms, modrmv};
+use core::fmt;
+use std::{fs::File, io::Read, process::exit};
 
 #[derive(Debug)]
 /// Generic errors, which are encountered during parsing.

src/disasm_macros.rs

@@ -1,3 +1,5 @@
+//! Some macros to help with disassembly parsing.
+
 #[macro_export]
 /// Generate a Mnemonic for an 8-bit Register from a ModRM byte.
 macro_rules! modrmb {

src/instructions.rs

@@ -1,38 +1,11 @@
+//! Internal abstraction of the 8086 instructions.
+
+use crate::{
+    operands::{Byte, MemoryIndex, ModRmTarget, Pointer, Word},
+    register::{Register, SegmentRegister},
+};
 use core::fmt;
 
-use crate::register::{Register, SegmentRegister};
-
-pub type Byte = u8; // b
-pub type IByte = i8; // used for displacements of memory access
-pub type Word = u16; // w or v
-pub type IWord = i16; // used for displacement of memory access
-
-#[derive(Debug, Clone)]
-#[allow(dead_code)]
-/// Encodes either Byte- or Word-sized operands.
-pub enum Operand {
-    Byte(Byte),
-    Word(Word),
-}
-
-impl fmt::Display for Operand {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match self {
-            Self::Byte(byte) => write!(f, "{}", byte),
-            Self::Word(word) => write!(f, "{}", word),
-        }
-    }
-}
-
-impl fmt::LowerHex for Operand {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self {
-            Self::Byte(b) => fmt::LowerHex::fmt(b, f),
-            Self::Word(v) => fmt::LowerHex::fmt(v, f),
-        }
-    }
-}
-
 #[derive(Debug, Clone)]
 #[allow(dead_code)]
 /// A single 'line' of executable ASM is called an Instruction, which
@@ -561,108 +534,3 @@ impl fmt::Display for Mnemonic {
         }
     }
 }
-
-#[derive(Debug, Clone)]
-/// ModRM byte can either target a memory location or some register
-pub enum ModRmTarget {
-    Memory(MemoryIndex),
-    Register(Register),
-}
-
-impl std::fmt::Display for ModRmTarget {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        match self {
-            Self::Memory(idx) => write!(f, "{}", idx),
-            Self::Register(reg) => write!(f, "{}", reg),
-        }
-    }
-}
-
-#[derive(Debug, Clone)]
-/// Memory displacements are signed versions of u8 and u16.
-/// Encodes either Byte- or Word-sized operands.
-pub enum Displacement {
-    IByte(i8),
-    IWord(i16),
-}
-
-impl fmt::LowerHex for Displacement {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self {
-            Self::IByte(b) => fmt::LowerHex::fmt(b, f),
-            Self::IWord(v) => fmt::LowerHex::fmt(v, f),
-        }
-    }
-}
-
-impl std::fmt::Display for Displacement {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        match self {
-            Self::IByte(b) => {
-                if *b > 0 {
-                    write!(f, " + {:#x}", b)
-                } else {
-                    write!(f, " - {:#x}", b * -1)
-                }
-            }
-            Self::IWord(w) => {
-                if *w > 0 {
-                    write!(f, " + {:#x}", w)
-                } else {
-                    write!(f, " - {:#x}", w * -1)
-                }
-            }
-        }
-    }
-}
-
-/// A memory index operand is usually created by ModRM bytes or words.
-/// e.g. [bx+si]
-#[derive(Debug, Clone)]
-pub struct MemoryIndex {
-    pub base: Option<Register>,
-    pub index: Option<Register>,
-    pub displacement: Option<Displacement>,
-}
-
-impl fmt::Display for MemoryIndex {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        match &self.base {
-            Some(base) => match &self.index {
-                Some(index) => match &self.displacement {
-                    Some(displacement) => {
-                        write!(f, "[{} + {}{}]", base, index, displacement)
-                    }
-                    None => write!(f, "[{} + {}]", base, index),
-                },
-                None => match &self.displacement {
-                    Some(displacement) => write!(f, "[{}{}]", base, displacement),
-                    None => write!(f, "[{}]", base),
-                },
-            },
-            None => match &self.index {
-                Some(index) => match &self.displacement {
-                    Some(displacement) => write!(f, "[{}{}]", index, displacement),
-                    None => write!(f, "[{}]", index),
-                },
-                None => match &self.displacement {
-                    Some(displacement) => write!(f, "[{:#x}]", displacement),
-                    None => panic!("Memory Index without base, index and displacement"),
-                },
-            },
-        }
-    }
-}
-
-#[derive(Debug, Clone)]
-/// 32-bit segment:offset pointer (e.g. for CALL instruction)
-pub struct Pointer {
-    pub segment: Word,
-    pub offset: Word,
-}
-
-impl std::fmt::Display for Pointer {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        write!(f, "{}:{}", self.segment, self.offset)
-    }
-}

src/main.rs

@@ -4,6 +4,7 @@ mod aout;
 mod disasm;
 mod disasm_macros;
 mod instructions;
+mod operands;
 mod register;
 
 #[derive(Subcommand, Debug)]

src/operands.rs

@@ -0,0 +1,141 @@
+//! All types which a Mnemonic can have as some kind of operand.
+//! This includes things such as immediates, ModRM byte targets, etc. etc.
+
+use crate::register::Register;
+use core::fmt;
+
+pub type Byte = u8; // b
+pub type IByte = i8; // used for displacements of memory access
+pub type Word = u16; // w or v
+pub type IWord = i16; // used for displacement of memory access
+
+#[derive(Debug, Clone)]
+#[allow(dead_code)]
+/// Encodes either Byte- or Word-sized operands.
+pub enum Operand {
+    Byte(Byte),
+    Word(Word),
+}
+
+impl fmt::Display for Operand {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Self::Byte(byte) => write!(f, "{}", byte),
+            Self::Word(word) => write!(f, "{}", word),
+        }
+    }
+}
+
+impl fmt::LowerHex for Operand {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::Byte(b) => fmt::LowerHex::fmt(b, f),
+            Self::Word(v) => fmt::LowerHex::fmt(v, f),
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+/// ModRM byte can either target a memory location or some register
+pub enum ModRmTarget {
+    Memory(MemoryIndex),
+    Register(Register),
+}
+
+impl std::fmt::Display for ModRmTarget {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            Self::Memory(idx) => write!(f, "{}", idx),
+            Self::Register(reg) => write!(f, "{}", reg),
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+/// Memory displacements are signed versions of u8 and u16.
+/// Encodes either Byte- or Word-sized operands.
+pub enum Displacement {
+    IByte(i8),
+    IWord(i16),
+}
+
+impl fmt::LowerHex for Displacement {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            Self::IByte(b) => fmt::LowerHex::fmt(b, f),
+            Self::IWord(v) => fmt::LowerHex::fmt(v, f),
+        }
+    }
+}
+
+impl std::fmt::Display for Displacement {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            Self::IByte(b) => {
+                if *b > 0 {
+                    write!(f, " + {:#x}", b)
+                } else {
+                    write!(f, " - {:#x}", b * -1)
+                }
+            }
+            Self::IWord(w) => {
+                if *w > 0 {
+                    write!(f, " + {:#x}", w)
+                } else {
+                    write!(f, " - {:#x}", w * -1)
+                }
+            }
+        }
+    }
+}
+
+/// A memory index operand is usually created by ModRM bytes or words.
+/// e.g. [bx+si]
+#[derive(Debug, Clone)]
+pub struct MemoryIndex {
+    pub base: Option<Register>,
+    pub index: Option<Register>,
+    pub displacement: Option<Displacement>,
+}
+
+impl fmt::Display for MemoryIndex {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match &self.base {
+            Some(base) => match &self.index {
+                Some(index) => match &self.displacement {
+                    Some(displacement) => {
+                        write!(f, "[{} + {}{}]", base, index, displacement)
+                    }
+                    None => write!(f, "[{} + {}]", base, index),
+                },
+                None => match &self.displacement {
+                    Some(displacement) => write!(f, "[{}{}]", base, displacement),
+                    None => write!(f, "[{}]", base),
+                },
+            },
+            None => match &self.index {
+                Some(index) => match &self.displacement {
+                    Some(displacement) => write!(f, "[{}{}]", index, displacement),
+                    None => write!(f, "[{}]", index),
+                },
+                None => match &self.displacement {
+                    Some(displacement) => write!(f, "[{:#x}]", displacement),
+                    None => panic!("Memory Index without base, index and displacement"),
+                },
+            },
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+/// 32-bit segment:offset pointer (e.g. for CALL instruction)
+pub struct Pointer {
+    pub segment: Word,
+    pub offset: Word,
+}
+
+impl std::fmt::Display for Pointer {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}:{}", self.segment, self.offset)
+    }
+}

src/register.rs

@@ -1,6 +1,7 @@
-use core::fmt;
+//! Internal abstraction of all 8086 registers for disassembly.
 
-use crate::instructions::Operand;
+use crate::operands::Operand;
+use core::fmt;
 
 #[derive(Debug, Clone)]
 #[allow(dead_code)]