integrate with c-api

Cargo.lock

@@ -3237,8 +3237,10 @@ name = "wasmtime-c-api"
 version = "0.19.0"
 dependencies = [
  "anyhow",
+ "cap-std",
  "env_logger 0.8.2",
  "once_cell",
+ "wasi-cap-std-sync",
  "wasi-common",
  "wasmtime",
  "wasmtime-c-api-macros",

crates/c-api/Cargo.toml

@@ -28,11 +28,13 @@ wat = { version = "1.0.23", optional = true }
 
 # Optional dependencies for the `wasi` feature
 wasi-common = { path = "../wasi-common", optional = true }
+wasi-cap-std-sync = { path = "../wasi-common/cap-std-sync", optional = true }
 wasmtime-wasi = { path = "../wasi", optional = true }
+cap-std = { version = "0.12", optional = true }
 
 [features]
 default = ['jitdump', 'wat', 'wasi', 'cache']
 lightbeam = ["wasmtime/lightbeam"]
 jitdump = ["wasmtime/jitdump"]
 cache = ["wasmtime/cache"]
-wasi = ['wasi-common', 'wasmtime-wasi']
+wasi = ['wasi-common', 'wasi-cap-std-sync', 'wasmtime-wasi', 'cap-std']

crates/c-api/src/wasi.rs

@@ -1,16 +1,22 @@
 //! The WASI embedding API definitions for Wasmtime.
 use crate::{wasm_extern_t, wasm_importtype_t, wasm_store_t, wasm_trap_t};
 use anyhow::Result;
+use cap_std::fs::Dir;
+use std::cell::RefCell;
 use std::collections::HashMap;
 use std::ffi::CStr;
 use std::fs::File;
 use std::os::raw::{c_char, c_int};
 use std::path::{Path, PathBuf};
+use std::rc::Rc;
 use std::slice;
 use std::str;
-use wasi_common::{preopen_dir, WasiCtx, WasiCtxBuilder};
+use wasi_cap_std_sync::WasiCtxBuilder;
+use wasi_common::WasiCtx;
 use wasmtime::{Extern, Linker, Trap};
-use wasmtime_wasi::{old::snapshot_0::Wasi as WasiSnapshot0, Wasi as WasiPreview1};
+use wasmtime_wasi::{
+    snapshots::preview_0::Wasi as WasiSnapshot0, snapshots::preview_1::Wasi as WasiPreview1,
+};
 
 unsafe fn cstr_to_path<'a>(path: *const c_char) -> Option<&'a Path> {
     CStr::from_ptr(path).to_str().map(Path::new).ok()
@@ -39,7 +45,7 @@ pub struct wasi_config_t {
     stdin: Option<File>,
     stdout: Option<File>,
     stderr: Option<File>,
-    preopens: Vec<(File, PathBuf)>,
+    preopens: Vec<(Dir, PathBuf)>,
     inherit_args: bool,
     inherit_env: bool,
     inherit_stdin: bool,
@@ -180,7 +186,7 @@ pub unsafe extern "C" fn wasi_config_preopen_dir(
     };
 
     let dir = match cstr_to_path(path) {
-        Some(p) => match preopen_dir(p) {
+        Some(p) => match cap_std::fs::Dir::open_ambient_dir(p) {
             Ok(d) => d,
             Err(_) => return false,
         },
@@ -197,39 +203,57 @@ enum WasiInstance {
     Snapshot0(WasiSnapshot0),
 }
 
-fn create_wasi_ctx(config: wasi_config_t) -> Result<WasiCtx> {
+fn create_wasi_ctx(config: wasi_config_t) -> Result<Rc<RefCell<WasiCtx>>> {
-    use std::convert::TryFrom;
-    use wasi_common::OsFile;
     let mut builder = WasiCtxBuilder::new();
     if config.inherit_args {
-        builder.inherit_args();
+        builder = builder.inherit_args()?;
     } else if !config.args.is_empty() {
-        builder.args(config.args);
+        let args = config
+            .args
+            .into_iter()
+            .map(|bytes| Ok(String::from_utf8(bytes)?))
+            .collect::<Result<Vec<String>>>()?;
+        builder = builder.args(&args)?;
     }
     if config.inherit_env {
-        builder.inherit_env();
+        builder = builder.inherit_env()?;
     } else if !config.env.is_empty() {
-        builder.envs(config.env);
+        let env = config
+            .env
+            .into_iter()
+            .map(|(kbytes, vbytes)| {
+                let k = String::from_utf8(kbytes)?;
+                let v = String::from_utf8(vbytes)?;
+                Ok((k, v))
+            })
+            .collect::<Result<Vec<(String, String)>>>()?;
+        builder = builder.envs(&env)?;
     }
     if config.inherit_stdin {
-        builder.inherit_stdin();
+        builder = builder.inherit_stdin();
     } else if let Some(file) = config.stdin {
-        builder.stdin(OsFile::try_from(file)?);
+        let file = unsafe { cap_std::fs::File::from_std(file) };
+        let file = wasi_cap_std_sync::file::File::from_cap_std(file);
+        builder = builder.stdin(Box::new(file));
     }
     if config.inherit_stdout {
-        builder.inherit_stdout();
+        builder = builder.inherit_stdout();
     } else if let Some(file) = config.stdout {
-        builder.stdout(OsFile::try_from(file)?);
+        let file = unsafe { cap_std::fs::File::from_std(file) };
+        let file = wasi_cap_std_sync::file::File::from_cap_std(file);
+        builder = builder.stdout(Box::new(file));
     }
     if config.inherit_stderr {
-        builder.inherit_stderr();
+        builder = builder.inherit_stderr();
     } else if let Some(file) = config.stderr {
-        builder.stderr(OsFile::try_from(file)?);
+        let file = unsafe { cap_std::fs::File::from_std(file) };
+        let file = wasi_cap_std_sync::file::File::from_cap_std(file);
+        builder = builder.stderr(Box::new(file));
     }
-    for preopen in config.preopens {
+    for (dir, path) in config.preopens {
-        builder.preopened_dir(preopen.0, preopen.1);
+        builder = builder.preopened_dir(dir, path)?;
     }
-    Ok(builder.build()?)
+    Ok(Rc::new(RefCell::new(builder.build()?)))
 }
 
 #[repr(C)]

crates/wasi-common/cap-std-sync/src/lib.rs

@@ -50,6 +50,13 @@ impl WasiCtxBuilder {
         }
         Ok(s)
     }
+    pub fn inherit_args(self) -> Result<Self, wasi_common::StringArrayError> {
+        let mut s = self.0;
+        for arg in std::env::args() {
+            s = s.arg(&arg)?;
+        }
+        Ok(WasiCtxBuilder(s))
+    }
     pub fn stdin(self, f: Box<dyn WasiFile>) -> Self {
         WasiCtxBuilder(self.0.stdin(f))
     }
@@ -59,10 +66,17 @@ impl WasiCtxBuilder {
     pub fn stderr(self, f: Box<dyn WasiFile>) -> Self {
         WasiCtxBuilder(self.0.stderr(f))
     }
-    pub fn inherit_stdio(self) -> Self {
+    pub fn inherit_stdin(self) -> Self {
         self.stdin(Box::new(crate::stdio::stdin()))
-            .stdout(Box::new(crate::stdio::stdout()))
+    }
-            .stderr(Box::new(crate::stdio::stderr()))
+    pub fn inherit_stdout(self) -> Self {
+        self.stdout(Box::new(crate::stdio::stdout()))
+    }
+    pub fn inherit_stderr(self) -> Self {
+        self.stderr(Box::new(crate::stdio::stderr()))
+    }
+    pub fn inherit_stdio(self) -> Self {
+        self.inherit_stdin().inherit_stdout().inherit_stderr()
     }
     pub fn preopened_dir(
         self,