wip: Implement more of the uefi::runtime module

Author: nicholasbishop

uefi/src/runtime.rs

@@ -5,10 +5,16 @@
 //! functions after exiting boot services; see the "Calling Convention" section
 //! of the UEFI specification for details.
 
-use crate::table::{self};
-use crate::{Result, StatusExt};
+use crate::table::boot::MemoryDescriptor;
+use crate::table::runtime::{
+    ResetType, RuntimeServices, VariableAttributes, VariableStorageInfo, VariableVendor,
+};
+use crate::{table, CStr16, Result, Status, StatusExt};
 use core::ptr::{self, NonNull};
 
+#[cfg(feature = "alloc")]
+use {crate::table::runtime::VariableKey, alloc::boxed::Box, alloc::vec::Vec};
+
 pub use crate::table::runtime::{Daylight, Time, TimeCapabilities, TimeError, TimeParams};
 
 fn runtime_services_raw_panicking() -> NonNull<uefi_raw::table::runtime::RuntimeServices> {
@@ -18,6 +24,14 @@ fn runtime_services_raw_panicking() -> NonNull<uefi_raw::table::runtime::Runtime
     NonNull::new(st.runtime_services).expect("runtime services are not active")
 }
 
+// TODO
+#[track_caller]
+fn runtime_services() -> NonNull<RuntimeServices> {
+    let st = table::system_table_runtime().expect("runtime services are not available");
+    let ptr: *const _ = unsafe { st.runtime_services() };
+    NonNull::new(ptr.cast_mut()).unwrap()
+}
+
 /// Query the current time and date information.
 pub fn get_time() -> Result<Time> {
     let rt = runtime_services_raw_panicking();
@@ -55,3 +69,92 @@ pub unsafe fn set_time(time: &Time) -> Result {
     let time: *const Time = time;
     (rt.set_time)(time.cast()).to_result()
 }
+
+/// Get the size (in bytes) of a variable. This can be used to find out how
+/// big of a buffer should be passed in to `get_variable`.
+pub fn get_variable_size(name: &CStr16, vendor: &VariableVendor) -> Result<usize> {
+    unsafe { runtime_services().as_mut() }.get_variable_size(name, vendor)
+}
+
+/// Get the contents and attributes of a variable. The size of `buf` must
+/// be at least as big as the variable's size, although it can be
+/// larger. If it is too small, `BUFFER_TOO_SMALL` is returned.
+///
+/// On success, a tuple containing the variable's value (a slice of `buf`)
+/// and the variable's attributes is returned.
+pub fn get_variable<'a>(
+    name: &CStr16,
+    vendor: &VariableVendor,
+    buf: &'a mut [u8],
+) -> Result<(&'a [u8], VariableAttributes)> {
+    unsafe { runtime_services().as_mut() }.get_variable(name, vendor, buf)
+}
+
+/// Get the contents and attributes of a variable.
+#[cfg(feature = "alloc")]
+pub fn get_variable_boxed(
+    name: &CStr16,
+    vendor: &VariableVendor,
+) -> Result<(Box<[u8]>, VariableAttributes)> {
+    unsafe { runtime_services().as_mut() }.get_variable_boxed(name, vendor)
+}
+
+/// Get the names and vendor GUIDs of all currently-set variables.
+#[cfg(feature = "alloc")]
+pub fn variable_keys() -> Result<Vec<VariableKey>> {
+    unsafe { runtime_services().as_mut() }.variable_keys()
+}
+
+/// Set the value of a variable. This can be used to create a new variable,
+/// update an existing variable, or (when the size of `data` is zero)
+/// delete a variable.
+///
+/// # Warnings
+///
+/// The [`Status::WARN_RESET_REQUIRED`] warning will be returned when using
+/// this function to transition the Secure Boot mode to setup mode or audit
+/// mode if the firmware requires a reboot for that operation.
+pub fn set_variable(
+    name: &CStr16,
+    vendor: &VariableVendor,
+    attributes: VariableAttributes,
+    data: &[u8],
+) -> Result {
+    unsafe { runtime_services().as_mut() }.set_variable(name, vendor, attributes, data)
+}
+
+/// Deletes a UEFI variable.
+pub fn delete_variable(name: &CStr16, vendor: &VariableVendor) -> Result {
+    unsafe { runtime_services().as_mut() }.delete_variable(name, vendor)
+}
+
+/// Get information about UEFI variable storage space for the type
+/// of variable specified in `attributes`.
+///
+/// This operation is only supported starting with UEFI 2.0; earlier
+/// versions will fail with [`Status::UNSUPPORTED`].
+///
+/// See [`VariableStorageInfo`] for details of the information returned.
+pub fn query_variable_info(attributes: VariableAttributes) -> Result<VariableStorageInfo> {
+    unsafe { runtime_services().as_mut() }.query_variable_info(attributes)
+}
+
+/// Resets the computer.
+pub fn reset(rt: ResetType, status: Status, data: Option<&[u8]>) -> ! {
+    unsafe { runtime_services().as_mut() }.reset(rt, status, data)
+}
+
+/// TODO
+pub unsafe fn set_virtual_address_map(
+    map_size: usize,
+    desc_size: usize,
+    desc_version: u32,
+    virtual_map: *mut MemoryDescriptor,
+) -> Status {
+    unsafe { runtime_services().as_mut() }.set_virtual_address_map(
+        map_size,
+        desc_size,
+        desc_version,
+        virtual_map,
+    )
+}