Tools for calling GCC

Author: rlivings39

rust_src/driver.rs

@@ -27,7 +27,7 @@ pub fn driver_main(args: &arg_parser::Cli) -> Result<(), Error> {
 /// notcc main driver function taking CLI args and parsing them
 ///
 /// **Note**: Unless you're writing a CLI application, you should use `driver_main` instead
-pub fn driver_main_cli(args: &mut env::Args) -> Result<(), Error> {
+pub fn driver_main_cli(args: impl Iterator<Item = String>) -> Result<(), Error> {
   let args: arg_parser::ArgVec = args.collect();
   let cli = arg_parser::parse_arguments(args)?;
   driver_main(&cli)

rust_src/driver/system_cc.rs

@@ -3,11 +3,55 @@
 //! The system C compiler is used for preprocessing and final assembly
 
 use crate::error::Error;
+use std::ffi::OsStr;
+use std::process::Command;
 
+fn run_cc<I, S>(args: I, cc_name: Option<&str>) -> Result<std::process::Output, Error>
+where
+  I: IntoIterator<Item = S>,
+  S: AsRef<OsStr>,
+{
+  let cc_name = cc_name.unwrap_or("gcc");
+  let res = Command::new(cc_name).args(args).output();
+  let res = match res {
+    Err(e) => return Err(format!("Error launching {cc_name}: {e}")),
+    Ok(r) => r,
+  };
+  if !res.status.success() {
+    let stderr = String::from_utf8_lossy(&res.stderr);
+    return Err(stderr.into_owned());
+  }
+  Ok(res)
+}
 pub fn preprocess_file(file_name: &str, output_file_name: &str) -> Result<(), Error> {
+  run_cc(["-E", "-P", file_name, "-o", output_file_name], None)?;
   Ok(())
 }
 
 pub fn assemble_output(asm_file: &str, output_exe: &str) -> Result<(), Error> {
+  run_cc([asm_file, "-o", output_exe], None)?;
   Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn fail_run_cc() {
+    let args: [&str; 0] = [];
+    assert!(run_cc(args, Some("bogus_cc_name")).is_err())
+  }
+
+  #[test]
+  fn preprocess_negative() {
+    assert!(preprocess_file("bogus_input_file.c", "bogus_input_file.i").is_err());
+  }
+
+  #[test]
+  fn assemble_negative() {
+    assert!(assemble_output("bogus_input_file.c", "bogus_input_file.i").is_err());
+  }
+
+  // TODO add some positive tests. Look at the tempfile crate
+}

rust_src/lib.rs

@@ -1,5 +1,6 @@
 #![doc = include_str!("README.md")]
-mod driver;
 pub mod error;
 
 pub use driver::{arg_parser::Cli, driver_main, driver_main_cli};
+
+mod driver;

rust_src/main.rs

@@ -3,8 +3,7 @@ use notcc;
 use std::env;
 use std::process;
 fn main() {
-  // TODO why mut?
-  let res = notcc::driver_main_cli(&mut env::args());
+  let res = notcc::driver_main_cli(env::args());
   if let Err(s) = res {
     eprintln!("Error: {s}");
     process::exit(1);