fix linux

 * error.BadFd is not a valid error code. it would always be a bug to
   get this error code.
 * merge error.Io with existing error.InputOutput
 * merge error.PathNotFound with existing error.FileNotFound.
   Not all OS's support both.
 * add os.File.openReadC
 * add error.BadPathName for windows file operations with invalid
   characters
 * add os.toPosixPath to help stack allocate a null terminating byte
 * add some TODOs for other functions to investigate removing the
   allocator requirement
 * optimize some implementations to use the alternate functions when
   a null byte is already available
 * add a missing error.SkipZigTest
 * os.selfExePath uses a non-allocating API
 * os.selfExeDirPath uses a non-allocating API
 * os.path.real uses a non-allocating API
 * add os.path.realAlloc and os.path.realC
 * convert many windows syscalls to use the W versions (See #534)

Author: andrewrk

doc/docgen.zig

@@ -34,10 +34,10 @@ pub fn main() !void {
     const out_file_name = try (args_it.next(allocator) orelse @panic("expected output arg"));
     defer allocator.free(out_file_name);
 
-    var in_file = try os.File.openRead(allocator, in_file_name);
+    var in_file = try os.File.openRead(in_file_name);
     defer in_file.close();
 
-    var out_file = try os.File.openWrite(allocator, out_file_name);
+    var out_file = try os.File.openWrite(out_file_name);
     defer out_file.close();
 
     var file_in_stream = io.FileInStream.init(&in_file);
@@ -738,7 +738,7 @@ fn genHtml(allocator: *mem.Allocator, tokenizer: *Tokenizer, toc: *Toc, out: var
                 try out.print("<pre><code class=\"zig\">{}</code></pre>", escaped_source);
                 const name_plus_ext = try std.fmt.allocPrint(allocator, "{}.zig", code.name);
                 const tmp_source_file_name = try os.path.join(allocator, tmp_dir_name, name_plus_ext);
-                try io.writeFile(allocator, tmp_source_file_name, trimmed_raw_source);
+                try io.writeFile(tmp_source_file_name, trimmed_raw_source);
 
                 switch (code.id) {
                     Code.Id.Exe => |expected_outcome| {

example/cat/main.zig

@@ -20,7 +20,7 @@ pub fn main() !void {
         } else if (arg[0] == '-') {
             return usage(exe);
         } else {
-            var file = os.File.openRead(allocator, arg) catch |err| {
+            var file = os.File.openRead(arg) catch |err| {
                 warn("Unable to open file: {}\n", @errorName(err));
                 return err;
             };

src-self-hosted/compilation.zig

@@ -257,8 +257,6 @@ pub const Compilation = struct {
     pub const BuildError = error{
         OutOfMemory,
         EndOfStream,
-        BadFd,
-        Io,
         IsDir,
         Unexpected,
         SystemResources,
@@ -273,7 +271,6 @@ pub const Compilation = struct {
         NameTooLong,
         SystemFdQuotaExceeded,
         NoDevice,
-        PathNotFound,
         NoSpaceLeft,
         NotDir,
         FileSystem,
@@ -962,7 +959,7 @@ pub const Compilation = struct {
         if (self.root_src_path) |root_src_path| {
             const root_scope = blk: {
                 // TODO async/await os.path.real
-                const root_src_real_path = os.path.real(self.gpa(), root_src_path) catch |err| {
+                const root_src_real_path = os.path.realAlloc(self.gpa(), root_src_path) catch |err| {
                     try self.addCompileErrorCli(root_src_path, "unable to open: {}", @errorName(err));
                     return;
                 };

src-self-hosted/introspect.zig

@@ -22,7 +22,7 @@ pub fn testZigInstallPrefix(allocator: *mem.Allocator, test_path: []const u8) ![
 
 /// Caller must free result
 pub fn findZigLibDir(allocator: *mem.Allocator) ![]u8 {
-    const self_exe_path = try os.selfExeDirPath(allocator);
+    const self_exe_path = try os.selfExeDirPathAlloc(allocator);
     defer allocator.free(self_exe_path);
 
     var cur_path: []const u8 = self_exe_path;

src-self-hosted/libc_installation.zig

@@ -453,7 +453,7 @@ fn fileExists(path: []const u8) !bool {
     if (std.os.File.access(path)) |_| {
         return true;
     } else |err| switch (err) {
-        error.FileNotFound, error.PathNotFound, error.PermissionDenied => return false,
+        error.FileNotFound, error.PermissionDenied => return false,
         else => return error.FileSystem,
     }
 }

std/build.zig

@@ -1491,11 +1491,14 @@ pub const LibExeObjStep = struct {
                     }
 
                     if (!is_darwin) {
-                        const rpath_arg = builder.fmt("-Wl,-rpath,{}", os.path.real(builder.allocator, builder.pathFromRoot(builder.cache_root)) catch unreachable);
+                        const rpath_arg = builder.fmt("-Wl,-rpath,{}", try os.path.realAlloc(
+                            builder.allocator,
+                            builder.pathFromRoot(builder.cache_root),
+                        ));
                         defer builder.allocator.free(rpath_arg);
-                        cc_args.append(rpath_arg) catch unreachable;
+                        try cc_args.append(rpath_arg);
 
-                        cc_args.append("-rdynamic") catch unreachable;
+                        try cc_args.append("-rdynamic");
                     }
 
                     for (self.full_path_libs.toSliceConst()) |full_path_lib| {
@@ -1566,11 +1569,14 @@ pub const LibExeObjStep = struct {
                 cc_args.append("-o") catch unreachable;
                 cc_args.append(output_path) catch unreachable;
 
-                const rpath_arg = builder.fmt("-Wl,-rpath,{}", os.path.real(builder.allocator, builder.pathFromRoot(builder.cache_root)) catch unreachable);
+                const rpath_arg = builder.fmt("-Wl,-rpath,{}", try os.path.realAlloc(
+                    builder.allocator,
+                    builder.pathFromRoot(builder.cache_root),
+                ));
                 defer builder.allocator.free(rpath_arg);
-                cc_args.append(rpath_arg) catch unreachable;
+                try cc_args.append(rpath_arg);
 
-                cc_args.append("-rdynamic") catch unreachable;
+                try cc_args.append("-rdynamic");
 
                 {
                     var it = self.link_libs.iterator();

std/debug/index.zig

@@ -255,7 +255,7 @@ pub fn printSourceAtAddress(debug_info: *ElfStackTrace, out_stream: var, address
                         address,
                         compile_unit_name,
                     );
-                    if (printLineFromFile(debug_info.allocator(), out_stream, line_info)) {
+                    if (printLineFromFile(out_stream, line_info)) {
                         if (line_info.column == 0) {
                             try out_stream.write("\n");
                         } else {

std/event/fs.zig

@@ -78,8 +78,7 @@ pub async fn pwritev(loop: *Loop, fd: os.FileHandle, data: []const []const u8, o
         builtin.Os.macosx,
         builtin.Os.linux,
         => return await (async pwritevPosix(loop, fd, data, offset) catch unreachable),
-        builtin.Os.windows,
-        => return await (async pwritevWindows(loop, fd, data, offset) catch unreachable),
+        builtin.Os.windows => return await (async pwritevWindows(loop, fd, data, offset) catch unreachable),
         else => @compileError("Unsupported OS"),
     }
 }
@@ -147,7 +146,6 @@ pub async fn pwriteWindows(loop: *Loop, fd: os.FileHandle, data: []const u8, off
     }
 }
 
-
 /// data - just the inner references - must live until pwritev promise completes.
 pub async fn pwritevPosix(loop: *Loop, fd: os.FileHandle, data: []const []const u8, offset: usize) !void {
     // workaround for https://github.com/ziglang/zig/issues/1194
@@ -203,8 +201,7 @@ pub async fn preadv(loop: *Loop, fd: os.FileHandle, data: []const []u8, offset:
         builtin.Os.macosx,
         builtin.Os.linux,
         => return await (async preadvPosix(loop, fd, data, offset) catch unreachable),
-        builtin.Os.windows,
-        => return await (async preadvWindows(loop, fd, data, offset) catch unreachable),
+        builtin.Os.windows => return await (async preadvWindows(loop, fd, data, offset) catch unreachable),
         else => @compileError("Unsupported OS"),
     }
 }
@@ -222,7 +219,7 @@ pub async fn preadvWindows(loop: *Loop, fd: os.FileHandle, data: []const []u8, o
     var inner_off: usize = 0;
     while (true) {
         const v = data_copy[iov_i];
-        const amt_read = try await (async preadWindows(loop, fd, v[inner_off .. v.len-inner_off], offset + off) catch unreachable);
+        const amt_read = try await (async preadWindows(loop, fd, v[inner_off .. v.len - inner_off], offset + off) catch unreachable);
         off += amt_read;
         inner_off += amt_read;
         if (inner_off == v.len) {
@@ -340,16 +337,15 @@ pub async fn openPosix(
         resume @handle();
     }
 
-    const path_with_null = try std.cstr.addNullByte(loop.allocator, path);
-    defer loop.allocator.free(path_with_null);
+    const path_c = try std.os.toPosixPath(path);
 
     var req_node = RequestNode{
         .prev = null,
         .next = null,
         .data = Request{
             .msg = Request.Msg{
                 .Open = Request.Msg.Open{
-                    .path = path_with_null[0..path.len],
+                    .path = path_c[0..path.len],
                     .flags = flags,
                     .mode = mode,
                     .result = undefined,
@@ -408,8 +404,7 @@ pub async fn openWriteMode(loop: *Loop, path: []const u8, mode: os.File.Mode) os
             const flags = posix.O_LARGEFILE | posix.O_WRONLY | posix.O_CREAT | posix.O_CLOEXEC | posix.O_TRUNC;
             return await (async openPosix(loop, path, flags, os.File.default_mode) catch unreachable);
         },
-        builtin.Os.windows,
-        => return os.windowsOpen(
+        builtin.Os.windows => return os.windowsOpen(
             path,
             windows.GENERIC_WRITE,
             windows.FILE_SHARE_WRITE | windows.FILE_SHARE_READ | windows.FILE_SHARE_DELETE,
@@ -434,7 +429,7 @@ pub async fn openReadWrite(
 
         builtin.Os.windows => return os.windowsOpen(
             path,
-            windows.GENERIC_WRITE|windows.GENERIC_READ,
+            windows.GENERIC_WRITE | windows.GENERIC_READ,
             windows.FILE_SHARE_WRITE | windows.FILE_SHARE_READ | windows.FILE_SHARE_DELETE,
             windows.OPEN_ALWAYS,
             windows.FILE_ATTRIBUTE_NORMAL | windows.FILE_FLAG_OVERLAPPED,
@@ -510,8 +505,7 @@ pub const CloseOperation = struct {
                     self.loop.allocator.destroy(self);
                 }
             },
-            builtin.Os.windows,
-            => {
+            builtin.Os.windows => {
                 if (self.os_data.handle) |handle| {
                     os.close(handle);
                 }
@@ -529,8 +523,7 @@ pub const CloseOperation = struct {
                 self.os_data.close_req_node.data.msg.Close.fd = handle;
                 self.os_data.have_fd = true;
             },
-            builtin.Os.windows,
-            => {
+            builtin.Os.windows => {
                 self.os_data.handle = handle;
             },
             else => @compileError("Unsupported OS"),
@@ -545,8 +538,7 @@ pub const CloseOperation = struct {
             => {
                 self.os_data.have_fd = false;
             },
-            builtin.Os.windows,
-            => {
+            builtin.Os.windows => {
                 self.os_data.handle = null;
             },
             else => @compileError("Unsupported OS"),
@@ -561,8 +553,7 @@ pub const CloseOperation = struct {
                 assert(self.os_data.have_fd);
                 return self.os_data.close_req_node.data.msg.Close.fd;
             },
-            builtin.Os.windows,
-            => {
+            builtin.Os.windows => {
                 return self.os_data.handle.?;
             },
             else => @compileError("Unsupported OS"),
@@ -582,8 +573,7 @@ pub async fn writeFileMode(loop: *Loop, path: []const u8, contents: []const u8,
         builtin.Os.linux,
         builtin.Os.macosx,
         => return await (async writeFileModeThread(loop, path, contents, mode) catch unreachable),
-        builtin.Os.windows,
-        => return await (async writeFileWindows(loop, path, contents) catch unreachable),
+        builtin.Os.windows => return await (async writeFileWindows(loop, path, contents) catch unreachable),
         else => @compileError("Unsupported OS"),
     }
 }
@@ -1000,7 +990,7 @@ pub fn Watch(comptime V: type) type {
             const basename_utf16le_null = try std.unicode.utf8ToUtf16LeWithNull(self.channel.loop.allocator, basename);
             var basename_utf16le_null_consumed = false;
             defer if (!basename_utf16le_null_consumed) self.channel.loop.allocator.free(basename_utf16le_null);
-            const basename_utf16le_no_null = basename_utf16le_null[0..basename_utf16le_null.len-1];
+            const basename_utf16le_no_null = basename_utf16le_null[0 .. basename_utf16le_null.len - 1];
 
             const dir_handle = windows.CreateFileW(
                 dirname_utf16le.ptr,
@@ -1014,9 +1004,8 @@ pub fn Watch(comptime V: type) type {
             if (dir_handle == windows.INVALID_HANDLE_VALUE) {
                 const err = windows.GetLastError();
                 switch (err) {
-                    windows.ERROR.FILE_NOT_FOUND,
-                    windows.ERROR.PATH_NOT_FOUND,
-                    => return error.PathNotFound,
+                    windows.ERROR.FILE_NOT_FOUND => return error.FileNotFound,
+                    windows.ERROR.PATH_NOT_FOUND => return error.FileNotFound,
                     else => return os.unexpectedErrorWindows(err),
                 }
             }
@@ -1102,7 +1091,10 @@ pub fn Watch(comptime V: type) type {
 
             // TODO handle this error not in the channel but in the setup
             _ = os.windowsCreateIoCompletionPort(
-                dir_handle, self.channel.loop.os_data.io_port, completion_key, undefined,
+                dir_handle,
+                self.channel.loop.os_data.io_port,
+                completion_key,
+                undefined,
             ) catch |err| {
                 await (async self.channel.put(err) catch unreachable);
                 return;
@@ -1122,10 +1114,10 @@ pub fn Watch(comptime V: type) type {
                             &event_buf,
                             @intCast(windows.DWORD, event_buf.len),
                             windows.FALSE, // watch subtree
-                            windows.FILE_NOTIFY_CHANGE_FILE_NAME        | windows.FILE_NOTIFY_CHANGE_DIR_NAME     |
-                                windows.FILE_NOTIFY_CHANGE_ATTRIBUTES   | windows.FILE_NOTIFY_CHANGE_SIZE         |
-                                windows.FILE_NOTIFY_CHANGE_LAST_WRITE   | windows.FILE_NOTIFY_CHANGE_LAST_ACCESS  |
-                                windows.FILE_NOTIFY_CHANGE_CREATION     | windows.FILE_NOTIFY_CHANGE_SECURITY,
+                            windows.FILE_NOTIFY_CHANGE_FILE_NAME | windows.FILE_NOTIFY_CHANGE_DIR_NAME |
+                                windows.FILE_NOTIFY_CHANGE_ATTRIBUTES | windows.FILE_NOTIFY_CHANGE_SIZE |
+                                windows.FILE_NOTIFY_CHANGE_LAST_WRITE | windows.FILE_NOTIFY_CHANGE_LAST_ACCESS |
+                                windows.FILE_NOTIFY_CHANGE_CREATION | windows.FILE_NOTIFY_CHANGE_SECURITY,
                             null, // number of bytes transferred (unused for async)
                             &overlapped,
                             null, // completion routine - unused because we use IOCP
@@ -1152,7 +1144,7 @@ pub fn Watch(comptime V: type) type {
                             else => null,
                         };
                         if (emit) |id| {
-                            const basename_utf16le = ([*]u16)(&ev.FileName)[0..ev.FileNameLength/2];
+                            const basename_utf16le = ([*]u16)(&ev.FileName)[0 .. ev.FileNameLength / 2];
                             const user_value = blk: {
                                 const held = await (async dir.table_lock.acquire() catch unreachable);
                                 defer held.release();

std/os/child_process.zig

@@ -349,14 +349,7 @@ pub const ChildProcess = struct {
         };
 
         const any_ignore = (self.stdin_behavior == StdIo.Ignore or self.stdout_behavior == StdIo.Ignore or self.stderr_behavior == StdIo.Ignore);
-        const dev_null_fd = if (any_ignore) blk: {
-            const dev_null_path = "/dev/null";
-            var fixed_buffer_mem: [dev_null_path.len + 1]u8 = undefined;
-            var fixed_allocator = std.heap.FixedBufferAllocator.init(fixed_buffer_mem[0..]);
-            break :blk try os.posixOpen(&fixed_allocator.allocator, "/dev/null", posix.O_RDWR, 0);
-        } else blk: {
-            break :blk undefined;
-        };
+        const dev_null_fd = if (any_ignore) try os.posixOpenC(c"/dev/null", posix.O_RDWR, 0) else undefined;
         defer {
             if (any_ignore) os.close(dev_null_fd);
         }