Reorganize wasi-misc-tests. (#575)

* Reorganize wasi-misc-tests.

Move wasi-misc-tests out of wasi-common, to break a dependency cycle;
previously, wasmtime-* depended on wasi-common, but wasi-common
dev-dependended on wasmtime-*.

Now, wasi-common no longer dev-depends on wasmtime-*; instead, the
tests are in their own crate which depends on wasi-common and on
wasmtime-*.

Also, rename wasi-misc-tests to wasi-tests for simplicity.

This also removes the "wasm_tests" feature; it's replaced by the
"test-programs" feature.

* Update the CI script to use the new feature name.

* Update the CI script to use the new feature name in one more place.

* Change a `write!` to a `writeln!`.

crates/test-programs/wasi-tests/src/bin/truncation_rights.rs

@@ -0,0 +1,157 @@
+use std::{env, mem, process};
+use wasi::wasi_unstable;
+use wasi_tests::open_scratch_directory;
+use wasi_tests::utils::{cleanup_file, close_fd, create_file};
+use wasi_tests::wasi_wrappers::{wasi_fd_fdstat_get, wasi_path_open};
+
+unsafe fn test_truncation_rights(dir_fd: wasi_unstable::Fd) {
+    // Create a file in the scratch directory.
+    create_file(dir_fd, "file");
+
+    // Get the rights for the scratch directory.
+    let mut dir_fdstat: wasi_unstable::FdStat = mem::zeroed();
+    let mut status = wasi_fd_fdstat_get(dir_fd, &mut dir_fdstat);
+    assert_eq!(
+        status,
+        wasi_unstable::raw::__WASI_ESUCCESS,
+        "calling fd_fdstat on the scratch directory"
+    );
+    assert_eq!(
+        dir_fdstat.fs_filetype,
+        wasi_unstable::FILETYPE_DIRECTORY,
+        "expected the scratch directory to be a directory",
+    );
+    assert_eq!(
+        dir_fdstat.fs_flags, 0,
+        "expected the scratch directory to have no special flags",
+    );
+    assert_eq!(
+        dir_fdstat.fs_rights_base & wasi_unstable::RIGHT_FD_FILESTAT_SET_SIZE,
+        0,
+        "directories shouldn't have the fd_filestat_set_size right",
+    );
+
+    // If we have the right to set sizes from paths, test that it works.
+    if (dir_fdstat.fs_rights_base & wasi_unstable::RIGHT_PATH_FILESTAT_SET_SIZE) == 0 {
+        eprintln!("implementation doesn't support setting file sizes, skipping");
+    } else {
+        // Test that we can truncate the file.
+        let mut file_fd: wasi_unstable::Fd = wasi_unstable::Fd::max_value() - 1;
+        status = wasi_path_open(
+            dir_fd,
+            0,
+            "file",
+            wasi_unstable::O_TRUNC,
+            0,
+            0,
+            0,
+            &mut file_fd,
+        );
+        assert_eq!(
+            status,
+            wasi_unstable::raw::__WASI_ESUCCESS,
+            "truncating a file"
+        );
+        close_fd(file_fd);
+
+        let mut rights_base: wasi_unstable::Rights = dir_fdstat.fs_rights_base;
+        let mut rights_inheriting: wasi_unstable::Rights = dir_fdstat.fs_rights_inheriting;
+
+        if (rights_inheriting & wasi_unstable::RIGHT_FD_FILESTAT_SET_SIZE) == 0 {
+            eprintln!("implementation doesn't support setting file sizes through file descriptors, skipping");
+        } else {
+            rights_inheriting &= !wasi_unstable::RIGHT_FD_FILESTAT_SET_SIZE;
+            assert!(
+                wasi_unstable::fd_fdstat_set_rights(dir_fd, rights_base, rights_inheriting).is_ok(),
+                "droping fd_filestat_set_size inheriting right on a directory",
+            );
+        }
+
+        // Test that we can truncate the file without the
+        // wasi_unstable::RIGHT_FD_FILESTAT_SET_SIZE right.
+        status = wasi_path_open(
+            dir_fd,
+            0,
+            "file",
+            wasi_unstable::O_TRUNC,
+            0,
+            0,
+            0,
+            &mut file_fd,
+        );
+        assert_eq!(
+            status,
+            wasi_unstable::raw::__WASI_ESUCCESS,
+            "truncating a file without fd_filestat_set_size right",
+        );
+        close_fd(file_fd);
+
+        rights_base &= !wasi_unstable::RIGHT_PATH_FILESTAT_SET_SIZE;
+        assert!(
+            wasi_unstable::fd_fdstat_set_rights(dir_fd, rights_base, rights_inheriting).is_ok(),
+            "droping path_filestat_set_size base right on a directory",
+        );
+
+        // Test that clearing wasi_unstable::RIGHT_PATH_FILESTAT_SET_SIZE actually
+        // took effect.
+        status = wasi_fd_fdstat_get(dir_fd, &mut dir_fdstat);
+        assert_eq!(
+            status,
+            wasi_unstable::raw::__WASI_ESUCCESS,
+            "reading the fdstat from a directory",
+        );
+        assert_eq!(
+            (dir_fdstat.fs_rights_base & wasi_unstable::RIGHT_PATH_FILESTAT_SET_SIZE),
+            0,
+            "reading the fdstat from a directory",
+        );
+
+        // Test that we can't truncate the file without the
+        // wasi_unstable::RIGHT_PATH_FILESTAT_SET_SIZE right.
+        status = wasi_path_open(
+            dir_fd,
+            0,
+            "file",
+            wasi_unstable::O_TRUNC,
+            0,
+            0,
+            0,
+            &mut file_fd,
+        );
+        assert_eq!(
+            status,
+            wasi_unstable::raw::__WASI_ENOTCAPABLE,
+            "truncating a file without path_filestat_set_size right",
+        );
+        assert_eq!(
+            file_fd,
+            wasi_unstable::Fd::max_value(),
+            "failed open should set the file descriptor to -1",
+        );
+    }
+
+    cleanup_file(dir_fd, "file");
+}
+
+fn main() {
+    let mut args = env::args();
+    let prog = args.next().unwrap();
+    let arg = if let Some(arg) = args.next() {
+        arg
+    } else {
+        eprintln!("usage: {} <scratch directory>", prog);
+        process::exit(1);
+    };
+
+    // Open scratch directory
+    let dir_fd = match open_scratch_directory(&arg) {
+        Ok(dir_fd) => dir_fd,
+        Err(err) => {
+            eprintln!("{}", err);
+            process::exit(1)
+        }
+    };
+
+    // Run the tests.
+    unsafe { test_truncation_rights(dir_fd) }
+}