From a694f575adbe4ca6852cc7c9022101ebcfc3a8d7 Mon Sep 17 00:00:00 2001
From: Jakub Konka <kubkon@jakubkonka.com>
Date: Fri, 31 Jul 2020 00:31:11 +0200
Subject: [PATCH] Add some os.open and os.openat smoke tests

---
 lib/std/os/test.zig | 90 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)

diff --git a/lib/std/os/test.zig b/lib/std/os/test.zig
index cfa358ca72..3aa0d0b3be 100644
--- a/lib/std/os/test.zig
+++ b/lib/std/os/test.zig
@@ -3,6 +3,7 @@ const os = std.os;
 const testing = std.testing;
 const expect = testing.expect;
 const expectEqual = testing.expectEqual;
+const expectError = testing.expectError;
 const io = std.io;
 const fs = std.fs;
 const mem = std.mem;
@@ -19,6 +20,95 @@ const tmpDir = std.testing.tmpDir;
 const Dir = std.fs.Dir;
 const ArenaAllocator = std.heap.ArenaAllocator;
 
+test "open smoke test" {
+    if (builtin.os.tag == .windows) return error.SkipZigTest;
+    if (builtin.os.tag == .wasi) return error.SkipZigTest;
+
+    // TODO verify file attributes using `fstat`
+
+    var tmp = tmpDir(.{});
+    defer tmp.cleanup();
+
+    // Get base abs path
+    var arena = ArenaAllocator.init(testing.allocator);
+    defer arena.deinit();
+
+    const base_path = blk: {
+        const relative_path = try fs.path.join(&arena.allocator, &[_][]const u8{ "zig-cache", "tmp", tmp.sub_path[0..] });
+        break :blk try fs.realpathAlloc(&arena.allocator, relative_path);
+    };
+
+    var file_path: []u8 = undefined;
+    var fd: os.fd_t = undefined;
+
+    // Create some file using `open`.
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_file" });
+    fd = try os.open(file_path, os.O_RDWR | os.O_CREAT | os.O_EXCL, 0o666);
+    os.close(fd);
+
+    // Try this again with the same flags. This op should fail with error.PathAlreadyExists.
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_file" });
+    expectError(error.PathAlreadyExists, os.open(file_path, os.O_RDWR | os.O_CREAT | os.O_EXCL, 0o666));
+
+    // Try opening without `O_EXCL` flag.
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_file" });
+    fd = try os.open(file_path, os.O_RDWR | os.O_CREAT, 0o666);
+    os.close(fd);
+
+    // Try opening as a directory which should fail.
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_file" });
+    expectError(error.NotDir, os.open(file_path, os.O_RDWR | os.O_DIRECTORY, 0o666));
+
+    // Create some directory
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_dir" });
+    try os.mkdir(file_path, 0o666);
+
+    // Open dir using `open`
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_dir" });
+    fd = try os.open(file_path, os.O_RDONLY | os.O_DIRECTORY, 0o666);
+    os.close(fd);
+
+    // Try opening as file which should fail.
+    file_path = try fs.path.join(&arena.allocator, &[_][]const u8{ base_path, "some_dir" });
+    expectError(error.IsDir, os.open(file_path, os.O_RDWR, 0o666));
+}
+
+test "openat smoke test" {
+    if (builtin.os.tag == .windows) return error.SkipZigTest;
+    if (builtin.os.tag == .wasi) return error.SkipZigTest;
+
+    // TODO verify file attributes using `fstatat`
+
+    var tmp = tmpDir(.{});
+    defer tmp.cleanup();
+
+    var fd: os.fd_t = undefined;
+
+    // Create some file using `openat`.
+    fd = try os.openat(tmp.dir.fd, "some_file", os.O_RDWR | os.O_CREAT | os.O_EXCL, 0o666);
+    os.close(fd);
+
+    // Try this again with the same flags. This op should fail with error.PathAlreadyExists.
+    expectError(error.PathAlreadyExists, os.openat(tmp.dir.fd, "some_file", os.O_RDWR | os.O_CREAT | os.O_EXCL, 0o666));
+
+    // Try opening without `O_EXCL` flag.
+    fd = try os.openat(tmp.dir.fd, "some_file", os.O_RDWR | os.O_CREAT, 0o666);
+    os.close(fd);
+
+    // Try opening as a directory which should fail.
+    expectError(error.NotDir, os.openat(tmp.dir.fd, "some_file", os.O_RDWR | os.O_DIRECTORY, 0o666));
+
+    // Create some directory
+    try os.mkdirat(tmp.dir.fd, "some_dir", 0o666);
+
+    // Open dir using `open`
+    fd = try os.openat(tmp.dir.fd, "some_dir", os.O_RDONLY | os.O_DIRECTORY, 0o666);
+    os.close(fd);
+
+    // Try opening as file which should fail.
+    expectError(error.IsDir, os.openat(tmp.dir.fd, "some_dir", os.O_RDWR, 0o666));
+}
+
 test "symlink with relative paths" {
     if (builtin.os.tag == .wasi) return error.SkipZigTest;