Add an example to print trust anchors.

Author: jsha

Cargo.toml

@@ -19,6 +19,7 @@ webpki-roots = "0.22"
 ring = "0.16.5"
 untrusted = "0.7.0"
 rustls = "0.20"
+x509-parser = "0.9.2"
 
 [target.'cfg(windows)'.dependencies]
 schannel = "0.1.15"

examples/print-trust-anchors.rs

@@ -0,0 +1,13 @@
+// Print the Subject of all extracted trust anchors.
+
+use rustls_native_certs;
+use std::error::Error;
+use x509_parser::prelude::*;
+
+fn main() -> Result<(), Box<dyn Error>> {
+    for cert in rustls_native_certs::load_native_certs()? {
+        let (_, cert) = parse_x509_certificate(&cert.0)?;
+        println!("{}", cert.tbs_certificate.subject);
+    }
+    Ok(())
+}