Added metadata parsing for flash configuration

Cargo.toml

@@ -23,3 +23,5 @@ lazy_static = "1.4.0"
 colored = "1.8.3"
 probe-rs = { version = "0.6.2", git = "https://github.com/probe-rs/probe-rs" }
 gdb-server = { version = "0.6.1", git = "https://github.com/probe-rs/probe-rs" }
+cargo_toml = "0.8.0"
+serde = { version = "1.0.110", features = [ "derive" ] }

src/main.rs

@@ -2,6 +2,7 @@ mod logging;
 
 use structopt;
 
+use cargo_toml::Manifest;
 use colored::*;
 use failure::format_err;
 use indicatif::{MultiProgress, ProgressBar, ProgressStyle};
@@ -17,6 +18,8 @@ use std::{
 };
 use structopt::StructOpt;
 
+use serde::Deserialize;
+
 use probe_rs::{
     architecture::arm::ap::AccessPortError,
     config::TargetSelector,
@@ -140,6 +143,11 @@ const ARGUMENTS_TO_REMOVE: &[&str] = &[
     "log=",
 ];
 
+#[derive(Clone, Debug, PartialEq, Deserialize)]
+pub struct Meta {
+    pub chip: Option<String>,
+}
+
 fn main() {
     match main_try() {
         Ok(_) => (),
@@ -174,6 +182,13 @@ fn main_try() -> Result<(), failure::Error> {
 
     logging::init(opt.log);
 
+    // Load cargo manifest if available and parse out meta object
+    // TODO: should we pull out a relative path here?
+    let meta = match Manifest::<Meta>::from_path_with_metadata("Cargo.toml") {
+        Ok(m) => m.package.map(|p| p.metadata).flatten(),
+        Err(_e) => None,
+    };
+
     // Make sure we load the config given in the cli parameters.
     if let Some(cdp) = opt.chip_description_path {
         probe_rs::config::registry::add_target_from_yaml(&Path::new(&cdp))?;
@@ -183,9 +198,12 @@ fn main_try() -> Result<(), failure::Error> {
         print_families()?;
         std::process::exit(0);
     } else {
-        opt.chip
-            .map(|chip| chip.into())
-            .unwrap_or(TargetSelector::Auto)
+        // First use command line, then manifest, then default to auto
+        match (opt.chip, meta.map(|m| m.chip).flatten()) {
+            (Some(c), _) => c.into(),
+            (_, Some(c)) => c.into(),
+            _ => TargetSelector::Auto,
+        }
     };
 
     args.remove(0); // Remove executable name