ShellParams: Add example app

Signed-off-by: Daniel Schaefer <[email protected]>

Author: JohnAZoidberg

uefi-test-runner/examples/shell_params.rs

@@ -0,0 +1,57 @@
+// ANCHOR: all
+// ANCHOR: features
+#![no_main]
+#![no_std]
+// ANCHOR_END: features
+
+use log::error;
+// ANCHOR: use
+//use log::info;
+use uefi::CStr16;
+use uefi::{prelude::*, proto::shell_params::ShellParameters};
+use uefi_services::println;
+
+extern crate alloc;
+use alloc::string::String;
+use alloc::vec::Vec;
+// ANCHOR_END: use
+
+// ANCHOR: entry
+#[entry]
+fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
+    // ANCHOR_END: entry
+    // ANCHOR: services
+    uefi_services::init(&mut system_table).unwrap();
+    let boot_services = system_table.boot_services();
+    // ANCHOR_END: services
+
+    // ANCHOR: params
+    let shell_params =
+        boot_services.open_protocol_exclusive::<ShellParameters>(image_handle);
+    let shell_params = match shell_params {
+        Ok(s) => s,
+        Err(e) => {
+            error!("Failed to get ShellParameters protocol");
+            return e.status();
+        }
+    };
+
+    // Get as Vec of String, only with alloc feature
+    let args: Vec<String> = shell_params.get_args().collect();
+    println!("Args: {:?}", args);
+
+    // Or without allocating, get a slice of the pointers
+    let args = shell_params.get_args_slice();
+    println!("Num args: {}", args.len());
+    if args.len() > 1 {
+        unsafe {
+            println!("First real arg: '{}'", CStr16::from_ptr(args[1]));
+        }
+    }
+    // ANCHOR_END: params
+
+    // ANCHOR: return
+    Status::SUCCESS
+}
+// ANCHOR_END: return
+// ANCHOR_END: all