initial

proc_macro/src/lib.rs

@@ -0,0 +1,12 @@
+#![feature(proc_macro_quote)]
+#![feature(proc_macro_span)]
+#![feature(custom_inner_attributes)]
+
+use proc_macro::*;
+
+mod sigscan;
+
+#[proc_macro]
+pub fn signature(input: TokenStream) -> TokenStream {
+    sigscan::macro_proc(input)
+}

proc_macro/src/sigscan.rs

@@ -0,0 +1,50 @@
+extern crate proc_macro;
+use proc_macro::*;
+use syn::*;
+
+enum Operation {
+    Byte(u8),
+    Wildcard,
+}
+
+fn generate_scanner(operations: Vec<Operation>) -> TokenStream {
+    let mut output: String = "| b: &[u8] | -> Option<usize> {\n".to_string();
+
+    output.push_str(format!("for i in 0..b.len()-{} {{",operations.len()).as_str());
+    for (i,op) in operations.iter().enumerate() {
+        if let Operation::Byte(byte) = op {
+            output.push_str(format!("if b[i+{}] != 0x{:x} {{ continue; }}", i, byte).as_str());
+        }
+    }
+
+    output.push_str("return Some(i);");
+    output.push_str("};");
+
+    output.push_str("None}");
+    output.parse().unwrap()
+}
+
+pub fn macro_proc(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as LitStr);
+    let input: String = input.value();
+
+    let mut operations = vec![];
+
+    for hex in input.split(" ") {
+        let op = if hex.eq("?") {
+            Operation::Wildcard
+        } else {
+            match u8::from_str_radix(hex, 16) {
+                Ok(hex) => {
+                    Operation::Byte(hex)
+                }
+                Err(e) => {
+                    panic!("{}", e);
+                }
+            }
+        };
+        operations.push(op);
+    }
+
+    return generate_scanner(operations);
+}