feat: add abi stable crates

__ffi/abi_stable_crates/interface/src/commands.rs

@@ -0,0 +1,154 @@
+use crate::{PluginId,WhichPlugin};
+
+use std::fmt;
+use serde::{
+    Serialize,Deserialize,
+    de::{self,Deserializer, DeserializeOwned, IgnoredAny, Visitor, MapAccess, Error as _},
+};
+use abi_stable::{StableAbi, std_types::*};
+
+/// The commands that map to methods in the Plugin trait.
+// This is intentionally not `#[derive(StableAbi)]`,
+// since it can be extended in minor versions of the interface.
+// I has to be serialized to pass it through ffi.
+#[derive(Debug,Clone,PartialEq,Eq,Serialize,Deserialize)]
+pub enum BasicCommand{
+    GetCommands,
+}
+
+
+/// These is the (serialized) return value of calling `PluginExt::send_basic_command`.
+// This is intentionally not `#[derive(StableAbi)]`,
+// since it can be extended in minor versions of the interface.
+// I has to be serialized to pass it through ffi.
+#[derive(Debug,Clone,PartialEq,Eq,Serialize,Deserialize)]
+pub enum BasicRetVal{
+    GetCommands(RVec<CommandDescription>),
+}
+
+
+// This is intentionally not `#[derive(StableAbi)]`,
+// since it can be extended in minor versions of the interface.
+// I has to be serialized to pass it through ffi.
+#[derive(Debug,Clone,PartialEq,Eq,Serialize,Deserialize)]
+#[serde(untagged)]
+pub enum CommandUnion<T>{
+    ForPlugin(T),
+    Basic(BasicCommand),
+}
+
+
+#[derive(Debug,Clone,PartialEq,Eq,Serialize,Deserialize)]
+#[serde(untagged)]
+pub enum ReturnValUnion<T>{
+    ForPlugin(T),
+    Basic(BasicRetVal),
+}
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+
+
+/// A partially deserialize command,that only deserialized its variant.
+#[derive(Debug,Clone)]
+pub struct WhichVariant{
+    pub variant:RString,
+}
+
+
+struct WhichVariantVisitor;
+
+impl<'de> Visitor<'de> for WhichVariantVisitor{
+    type Value = WhichVariant;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("a map with a single entry,or a string")
+    }
+
+    fn visit_str<E>(self, value: &str) -> Result<WhichVariant, E>
+    where
+        E: de::Error,
+    {
+        Ok(WhichVariant{variant:value.to_string().into()})
+    }
+
+    fn visit_map<M>(self, mut access: M) -> Result<Self::Value, M::Error>
+    where
+        M: MapAccess<'de>,
+    {
+        let (variant,_)=access.next_entry::<RString,IgnoredAny>()?
+            .ok_or_else(||M::Error::custom("Expected a map with a single entry"))?;
+        if let Some((second,_))=access.next_entry::<RString,IgnoredAny>()? {
+            let s=format!(
+                "Expected a map with a single field,\n\
+                 instead found both {{ \"{}\":... , \"{}\": ... }}",
+                 variant,
+                 second,
+            );
+            return Err(M::Error::custom(s));
+        }
+        Ok(WhichVariant{variant})
+    }
+}
+
+impl<'de> Deserialize<'de> for WhichVariant{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_map(WhichVariantVisitor)
+    }
+}
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+
+
+/// Denotes this as a command type.
+pub trait CommandTrait:Serialize{
+    type Returns:DeserializeOwned;
+}
+
+impl CommandTrait for BasicCommand{
+    type Returns=BasicRetVal;
+}
+
+
+/// Describes a command.
+#[repr(C)]
+#[derive(Debug,Clone,PartialEq,Eq,Serialize,Deserialize,StableAbi)]
+pub struct CommandDescription{
+    /// A description of what this command does.
+    pub name:RCow<'static,str>,
+    /// A description of what this command does,
+    /// optionally with a description of the command format.
+    pub description:RCow<'static,str>,
+}
+
+
+impl CommandDescription{
+    pub fn from_literals(
+        name:&'static str,
+        description:&'static str,
+    )->Self{
+        CommandDescription{
+            name:name.into(),
+            description:description.into(),
+        }
+    }
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+
+
+#[repr(C)]
+#[derive(Debug,Clone,PartialEq,Eq,StableAbi)]
+pub struct AsyncCommand{
+    pub from:PluginId,
+    pub which_plugin:WhichPlugin,
+    pub command:RString,
+}