commit d93edadead45e447e6bc16c0934a3031a06d0fd8 (tree)
parent 6ed0910d6d974750fe65990983d5347ceacc0186
Author: Andrew Kelley <andrew@ziglang.org>
Date: Sun, 18 Dec 2022 16:22:19 -0500
Merge pull request #13993 from squeek502/windows-childprocess-perf
`spawnWindows`: Improve worst-case performance considerably + tests
Diffstat:
8 files changed, 589 insertions(+), 95 deletions(-)
diff --git a/lib/std/child_process.zig b/lib/std/child_process.zig
@@ -946,109 +946,105 @@ pub const ChildProcess = struct {
defer if (maybe_envp_buf) |envp_buf| self.allocator.free(envp_buf);
const envp_ptr = if (maybe_envp_buf) |envp_buf| envp_buf.ptr else null;
+ const app_name_utf8 = self.argv[0];
+ const app_name_is_absolute = fs.path.isAbsolute(app_name_utf8);
+
// the cwd set in ChildProcess is in effect when choosing the executable path
// to match posix semantics
- const app_path = x: {
- if (self.cwd) |cwd| {
- const resolved = try fs.path.resolve(self.allocator, &[_][]const u8{ cwd, self.argv[0] });
- defer self.allocator.free(resolved);
- break :x try cstr.addNullByte(self.allocator, resolved);
+ var cwd_path_w_needs_free = false;
+ const cwd_path_w = x: {
+ // If the app name is absolute, then we need to use its dirname as the cwd
+ if (app_name_is_absolute) {
+ cwd_path_w_needs_free = true;
+ const dir = fs.path.dirname(app_name_utf8).?;
+ break :x try unicode.utf8ToUtf16LeWithNull(self.allocator, dir);
+ } else if (self.cwd) |cwd| {
+ cwd_path_w_needs_free = true;
+ break :x try unicode.utf8ToUtf16LeWithNull(self.allocator, cwd);
} else {
- break :x try cstr.addNullByte(self.allocator, self.argv[0]);
+ break :x &[_:0]u16{}; // empty for cwd
+ }
+ };
+ defer if (cwd_path_w_needs_free) self.allocator.free(cwd_path_w);
+
+ // If the app name has more than just a filename, then we need to separate that
+ // into the basename and dirname and use the dirname as an addition to the cwd
+ // path. This is because NtQueryDirectoryFile cannot accept FileName params with
+ // path separators.
+ const app_basename_utf8 = fs.path.basename(app_name_utf8);
+ // If the app name is absolute, then the cwd will already have the app's dirname in it,
+ // so only populate app_dirname if app name is a relative path with > 0 path separators.
+ const maybe_app_dirname_utf8 = if (!app_name_is_absolute) fs.path.dirname(app_name_utf8) else null;
+ const app_dirname_w: ?[:0]u16 = x: {
+ if (maybe_app_dirname_utf8) |app_dirname_utf8| {
+ break :x try unicode.utf8ToUtf16LeWithNull(self.allocator, app_dirname_utf8);
}
+ break :x null;
};
- defer self.allocator.free(app_path);
+ defer if (app_dirname_w != null) self.allocator.free(app_dirname_w.?);
- const app_path_w = try unicode.utf8ToUtf16LeWithNull(self.allocator, app_path);
- defer self.allocator.free(app_path_w);
+ const app_name_w = try unicode.utf8ToUtf16LeWithNull(self.allocator, app_basename_utf8);
+ defer self.allocator.free(app_name_w);
const cmd_line_w = try unicode.utf8ToUtf16LeWithNull(self.allocator, cmd_line);
defer self.allocator.free(cmd_line_w);
exec: {
- windowsCreateProcess(app_path_w.ptr, cmd_line_w.ptr, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo) catch |no_path_err| {
- switch (no_path_err) {
- error.FileNotFound, error.InvalidExe => {},
- else => |e| return e,
- }
+ const PATH: [:0]const u16 = std.os.getenvW(unicode.utf8ToUtf16LeStringLiteral("PATH")) orelse &[_:0]u16{};
+ const PATHEXT: [:0]const u16 = std.os.getenvW(unicode.utf8ToUtf16LeStringLiteral("PATHEXT")) orelse &[_:0]u16{};
- const PATH: [:0]const u16 = std.os.getenvW(unicode.utf8ToUtf16LeStringLiteral("PATH")) orelse &[_:0]u16{};
- const PATHEXT: [:0]const u16 = std.os.getenvW(unicode.utf8ToUtf16LeStringLiteral("PATHEXT")) orelse &[_:0]u16{};
-
- var path_buf = std.ArrayListUnmanaged(u16){};
- defer path_buf.deinit(self.allocator);
-
- // Try again with PATHEXT's extensions appended
- {
- try path_buf.appendSlice(self.allocator, app_path_w);
- var ext_it = mem.tokenize(u16, PATHEXT, &[_]u16{';'});
- while (ext_it.next()) |ext| {
- path_buf.shrinkRetainingCapacity(app_path_w.len);
- try path_buf.appendSlice(self.allocator, ext);
- try path_buf.append(self.allocator, 0);
- const path_with_ext = path_buf.items[0 .. path_buf.items.len - 1 :0];
-
- if (windowsCreateProcess(path_with_ext.ptr, cmd_line_w.ptr, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo)) |_| {
- break :exec;
- } else |err| switch (err) {
- error.FileNotFound, error.AccessDenied, error.InvalidExe => {},
- else => return err,
- }
- }
- }
+ var app_buf = std.ArrayListUnmanaged(u16){};
+ defer app_buf.deinit(self.allocator);
- // No need to search the PATH if the app path is absolute
- if (fs.path.isAbsoluteWindowsWTF16(app_path_w)) return no_path_err;
-
- // app_path_w has the cwd prepended to it if cwd is non-null, so when
- // searching the PATH we should make sure we use the app_name verbatim.
- var app_name_w_needs_free = false;
- const app_name_w = x: {
- if (self.cwd) |_| {
- app_name_w_needs_free = true;
- break :x try unicode.utf8ToUtf16LeWithNull(self.allocator, self.argv[0]);
- } else {
- break :x app_path_w;
- }
+ try app_buf.appendSlice(self.allocator, app_name_w);
+
+ var dir_buf = std.ArrayListUnmanaged(u16){};
+ defer dir_buf.deinit(self.allocator);
+
+ if (cwd_path_w.len > 0) {
+ try dir_buf.appendSlice(self.allocator, cwd_path_w);
+ }
+ if (app_dirname_w) |app_dir| {
+ if (dir_buf.items.len > 0) try dir_buf.append(self.allocator, fs.path.sep);
+ try dir_buf.appendSlice(self.allocator, app_dir);
+ }
+ if (dir_buf.items.len > 0) {
+ // Need to normalize the path, openDirW can't handle things like double backslashes
+ const normalized_len = windows.normalizePath(u16, dir_buf.items) catch return error.BadPathName;
+ dir_buf.shrinkRetainingCapacity(normalized_len);
+ }
+
+ windowsCreateProcessPathExt(self.allocator, &dir_buf, &app_buf, PATHEXT, cmd_line_w.ptr, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo) catch |no_path_err| {
+ var original_err = switch (no_path_err) {
+ error.FileNotFound, error.InvalidExe, error.AccessDenied => |e| e,
+ error.UnrecoverableInvalidExe => return error.InvalidExe,
+ else => |e| return e,
};
- defer if (app_name_w_needs_free) self.allocator.free(app_name_w);
+
+ // If the app name had path separators, that disallows PATH searching,
+ // and there's no need to search the PATH if the cwd path is absolute.
+ if (app_dirname_w != null or fs.path.isAbsoluteWindowsWTF16(cwd_path_w)) {
+ return original_err;
+ }
var it = mem.tokenize(u16, PATH, &[_]u16{';'});
while (it.next()) |search_path| {
- path_buf.clearRetainingCapacity();
- const search_path_trimmed = mem.trimRight(u16, search_path, &[_]u16{ '\\', '/' });
- try path_buf.appendSlice(self.allocator, search_path_trimmed);
- try path_buf.append(self.allocator, fs.path.sep);
- const app_name_trimmed = mem.trimLeft(u16, app_name_w, &[_]u16{ '\\', '/' });
- try path_buf.appendSlice(self.allocator, app_name_trimmed);
- try path_buf.append(self.allocator, 0);
- const path_no_ext = path_buf.items[0 .. path_buf.items.len - 1 :0];
-
- if (windowsCreateProcess(path_no_ext.ptr, cmd_line_w.ptr, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo)) |_| {
+ dir_buf.clearRetainingCapacity();
+ try dir_buf.appendSlice(self.allocator, search_path);
+ // Need to normalize the path, some PATH values can contain things like double
+ // backslashes which openDirW can't handle
+ const normalized_len = windows.normalizePath(u16, dir_buf.items) catch continue;
+ dir_buf.shrinkRetainingCapacity(normalized_len);
+
+ if (windowsCreateProcessPathExt(self.allocator, &dir_buf, &app_buf, PATHEXT, cmd_line_w.ptr, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo)) {
break :exec;
} else |err| switch (err) {
- error.FileNotFound, error.AccessDenied, error.InvalidExe => {},
- else => return err,
- }
-
- var ext_it = mem.tokenize(u16, PATHEXT, &[_]u16{';'});
- while (ext_it.next()) |ext| {
- path_buf.shrinkRetainingCapacity(path_no_ext.len);
- try path_buf.appendSlice(self.allocator, ext);
- try path_buf.append(self.allocator, 0);
- const joined_path = path_buf.items[0 .. path_buf.items.len - 1 :0];
-
- if (windowsCreateProcess(joined_path.ptr, cmd_line_w.ptr, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo)) |_| {
- break :exec;
- } else |err| switch (err) {
- error.FileNotFound => continue,
- error.AccessDenied => continue,
- error.InvalidExe => continue,
- else => return err,
- }
+ error.FileNotFound, error.AccessDenied, error.InvalidExe => continue,
+ error.UnrecoverableInvalidExe => return error.InvalidExe,
+ else => |e| return e,
}
} else {
- return no_path_err; // return the original error
+ return original_err;
}
};
}
@@ -1094,6 +1090,235 @@ pub const ChildProcess = struct {
}
};
+/// Expects `app_buf` to contain exactly the app name, and `dir_buf` to contain exactly the dir path.
+/// After return, `app_buf` will always contain exactly the app name and `dir_buf` will always contain exactly the dir path.
+/// Note: `app_buf` should not contain any leading path separators.
+/// Note: If the dir is the cwd, dir_buf should be empty (len = 0).
+fn windowsCreateProcessPathExt(
+ allocator: mem.Allocator,
+ dir_buf: *std.ArrayListUnmanaged(u16),
+ app_buf: *std.ArrayListUnmanaged(u16),
+ pathext: [:0]const u16,
+ cmd_line: [*:0]u16,
+ envp_ptr: ?[*]u16,
+ cwd_ptr: ?[*:0]u16,
+ lpStartupInfo: *windows.STARTUPINFOW,
+ lpProcessInformation: *windows.PROCESS_INFORMATION,
+) !void {
+ const app_name_len = app_buf.items.len;
+ const dir_path_len = dir_buf.items.len;
+
+ if (app_name_len == 0) return error.FileNotFound;
+
+ defer app_buf.shrinkRetainingCapacity(app_name_len);
+ defer dir_buf.shrinkRetainingCapacity(dir_path_len);
+
+ // The name of the game here is to avoid CreateProcessW calls at all costs,
+ // and only ever try calling it when we have a real candidate for execution.
+ // Secondarily, we want to minimize the number of syscalls used when checking
+ // for each PATHEXT-appended version of the app name.
+ //
+ // An overview of the technique used:
+ // - Open the search directory for iteration (either cwd or a path from PATH)
+ // - Use NtQueryDirectoryFile with a wildcard filename of `<app name>*` to
+ // check if anything that could possibly match either the unappended version
+ // of the app name or any of the versions with a PATHEXT value appended exists.
+ // - If the wildcard NtQueryDirectoryFile call found nothing, we can exit early
+ // without needing to use PATHEXT at all.
+ //
+ // This allows us to use a <open dir, NtQueryDirectoryFile, close dir> sequence
+ // for any directory that doesn't contain any possible matches, instead of having
+ // to use a separate look up for each individual filename combination (unappended +
+ // each PATHEXT appended). For directories where the wildcard *does* match something,
+ // we only need to do a maximum of <number of supported PATHEXT extensions> more
+ // NtQueryDirectoryFile calls.
+
+ var dir = dir: {
+ if (fs.path.isAbsoluteWindowsWTF16(dir_buf.items[0..dir_path_len])) {
+ const prefixed_path = try windows.wToPrefixedFileW(dir_buf.items[0..dir_path_len]);
+ break :dir fs.cwd().openDirW(prefixed_path.span().ptr, .{}, true) catch return error.FileNotFound;
+ }
+ // needs to be null-terminated
+ try dir_buf.append(allocator, 0);
+ defer dir_buf.shrinkRetainingCapacity(dir_buf.items[0..dir_path_len].len);
+ const dir_path_z = dir_buf.items[0 .. dir_buf.items.len - 1 :0];
+ break :dir std.fs.cwd().openDirW(dir_path_z.ptr, .{}, true) catch return error.FileNotFound;
+ };
+ defer dir.close();
+
+ // Add wildcard and null-terminator
+ try app_buf.append(allocator, '*');
+ try app_buf.append(allocator, 0);
+ const app_name_wildcard = app_buf.items[0 .. app_buf.items.len - 1 :0];
+
+ // Enough for the FILE_DIRECTORY_INFORMATION + (NAME_MAX UTF-16 code units [2 bytes each]).
+ const file_info_buf_size = @sizeOf(windows.FILE_DIRECTORY_INFORMATION) + (windows.NAME_MAX * 2);
+ var file_information_buf: [file_info_buf_size]u8 align(@alignOf(os.windows.FILE_DIRECTORY_INFORMATION)) = undefined;
+ var io_status: windows.IO_STATUS_BLOCK = undefined;
+ const found_name: ?[]const u16 = found_name: {
+ const app_name_len_bytes = math.cast(u16, app_name_wildcard.len * 2) orelse return error.NameTooLong;
+ var app_name_unicode_string = windows.UNICODE_STRING{
+ .Length = app_name_len_bytes,
+ .MaximumLength = app_name_len_bytes,
+ .Buffer = @intToPtr([*]u16, @ptrToInt(app_name_wildcard.ptr)),
+ };
+ const rc = windows.ntdll.NtQueryDirectoryFile(
+ dir.fd,
+ null,
+ null,
+ null,
+ &io_status,
+ &file_information_buf,
+ file_information_buf.len,
+ .FileDirectoryInformation,
+ // TODO: It might be better to iterate over all wildcard matches and
+ // only pick the ones that match an appended PATHEXT instead of only
+ // using the wildcard as a lookup and then restarting iteration
+ // on future NtQueryDirectoryFile calls.
+ //
+ // However, note that this could lead to worse outcomes in the
+ // case of a very generic command name (e.g. "a"), so it might
+ // be better to only use the wildcard to determine if it's worth
+ // checking with PATHEXT (this is the current behavior).
+ windows.TRUE, // single result
+ &app_name_unicode_string,
+ windows.TRUE, // restart iteration
+ );
+
+ // If we get nothing with the wildcard, then we can just bail out
+ // as we know appending PATHEXT will not yield anything.
+ switch (rc) {
+ .SUCCESS => {},
+ .NO_SUCH_FILE => return error.FileNotFound,
+ .NO_MORE_FILES => return error.FileNotFound,
+ .ACCESS_DENIED => return error.AccessDenied,
+ else => return windows.unexpectedStatus(rc),
+ }
+
+ const dir_info = @ptrCast(*windows.FILE_DIRECTORY_INFORMATION, &file_information_buf);
+ if (dir_info.FileAttributes & windows.FILE_ATTRIBUTE_DIRECTORY != 0) {
+ break :found_name null;
+ }
+ break :found_name @ptrCast([*]u16, &dir_info.FileName)[0 .. dir_info.FileNameLength / 2];
+ };
+
+ const unappended_err = unappended: {
+ // NtQueryDirectoryFile returns results in order by filename, so the first result of
+ // the wildcard call will always be the unappended version if it exists. So, if found_name
+ // is not the unappended version, we can skip straight to trying versions with PATHEXT appended.
+ // TODO: This might depend on the filesystem, though; need to somehow verify that it always
+ // works this way.
+ if (found_name != null and windows.eqlIgnoreCaseWTF16(found_name.?, app_buf.items[0..app_name_len])) {
+ if (dir_path_len != 0) switch (dir_buf.items[dir_buf.items.len - 1]) {
+ '/', '\\' => {},
+ else => try dir_buf.append(allocator, fs.path.sep),
+ };
+ try dir_buf.appendSlice(allocator, app_buf.items[0..app_name_len]);
+ try dir_buf.append(allocator, 0);
+ const full_app_name = dir_buf.items[0 .. dir_buf.items.len - 1 :0];
+
+ if (windowsCreateProcess(full_app_name.ptr, cmd_line, envp_ptr, cwd_ptr, lpStartupInfo, lpProcessInformation)) |_| {
+ return;
+ } else |err| switch (err) {
+ error.FileNotFound,
+ error.AccessDenied,
+ => break :unappended err,
+ error.InvalidExe => {
+ // On InvalidExe, if the extension of the app name is .exe then
+ // it's treated as an unrecoverable error. Otherwise, it'll be
+ // skipped as normal.
+ const app_name = app_buf.items[0..app_name_len];
+ const ext_start = std.mem.lastIndexOfScalar(u16, app_name, '.') orelse break :unappended err;
+ const ext = app_name[ext_start..];
+ if (windows.eqlIgnoreCaseWTF16(ext, unicode.utf8ToUtf16LeStringLiteral(".EXE"))) {
+ return error.UnrecoverableInvalidExe;
+ }
+ break :unappended err;
+ },
+ else => return err,
+ }
+ }
+ break :unappended error.FileNotFound;
+ };
+
+ // Now we know that at least *a* file matching the wildcard exists, we can loop
+ // through PATHEXT in order and exec any that exist
+
+ var ext_it = mem.tokenize(u16, pathext, &[_]u16{';'});
+ while (ext_it.next()) |ext| {
+ if (!windowsCreateProcessSupportsExtension(ext)) continue;
+
+ app_buf.shrinkRetainingCapacity(app_name_len);
+ try app_buf.appendSlice(allocator, ext);
+ try app_buf.append(allocator, 0);
+ const app_name_appended = app_buf.items[0 .. app_buf.items.len - 1 :0];
+
+ const app_name_len_bytes = math.cast(u16, app_name_appended.len * 2) orelse return error.NameTooLong;
+ var app_name_unicode_string = windows.UNICODE_STRING{
+ .Length = app_name_len_bytes,
+ .MaximumLength = app_name_len_bytes,
+ .Buffer = @intToPtr([*]u16, @ptrToInt(app_name_appended.ptr)),
+ };
+
+ // Re-use the directory handle but this time we call with the appended app name
+ // with no wildcard.
+ const rc = windows.ntdll.NtQueryDirectoryFile(
+ dir.fd,
+ null,
+ null,
+ null,
+ &io_status,
+ &file_information_buf,
+ file_information_buf.len,
+ .FileDirectoryInformation,
+ windows.TRUE, // single result
+ &app_name_unicode_string,
+ windows.TRUE, // restart iteration
+ );
+
+ switch (rc) {
+ .SUCCESS => {},
+ .NO_SUCH_FILE => continue,
+ .NO_MORE_FILES => continue,
+ .ACCESS_DENIED => continue,
+ else => return windows.unexpectedStatus(rc),
+ }
+
+ const dir_info = @ptrCast(*windows.FILE_DIRECTORY_INFORMATION, &file_information_buf);
+ // Skip directories
+ if (dir_info.FileAttributes & windows.FILE_ATTRIBUTE_DIRECTORY != 0) continue;
+
+ dir_buf.shrinkRetainingCapacity(dir_path_len);
+ if (dir_path_len != 0) switch (dir_buf.items[dir_buf.items.len - 1]) {
+ '/', '\\' => {},
+ else => try dir_buf.append(allocator, fs.path.sep),
+ };
+ try dir_buf.appendSlice(allocator, app_buf.items[0..app_name_len]);
+ try dir_buf.appendSlice(allocator, ext);
+ try dir_buf.append(allocator, 0);
+ const full_app_name = dir_buf.items[0 .. dir_buf.items.len - 1 :0];
+
+ if (windowsCreateProcess(full_app_name.ptr, cmd_line, envp_ptr, cwd_ptr, lpStartupInfo, lpProcessInformation)) |_| {
+ return;
+ } else |err| switch (err) {
+ error.FileNotFound => continue,
+ error.AccessDenied => continue,
+ error.InvalidExe => {
+ // On InvalidExe, if the extension of the app name is .exe then
+ // it's treated as an unrecoverable error. Otherwise, it'll be
+ // skipped as normal.
+ if (windows.eqlIgnoreCaseWTF16(ext, unicode.utf8ToUtf16LeStringLiteral(".EXE"))) {
+ return error.UnrecoverableInvalidExe;
+ }
+ continue;
+ },
+ else => return err,
+ }
+ }
+
+ return unappended_err;
+}
+
fn windowsCreateProcess(app_name: [*:0]u16, cmd_line: [*:0]u16, envp_ptr: ?[*]u16, cwd_ptr: ?[*:0]u16, lpStartupInfo: *windows.STARTUPINFOW, lpProcessInformation: *windows.PROCESS_INFORMATION) !void {
// TODO the docs for environment pointer say:
// > A pointer to the environment block for the new process. If this parameter
@@ -1126,6 +1351,64 @@ fn windowsCreateProcess(app_name: [*:0]u16, cmd_line: [*:0]u16, envp_ptr: ?[*]u1
);
}
+/// Case-insenstive UTF-16 lookup
+fn windowsCreateProcessSupportsExtension(ext: []const u16) bool {
+ const State = enum {
+ start,
+ dot,
+ b,
+ ba,
+ c,
+ cm,
+ co,
+ e,
+ ex,
+ };
+ var state: State = .start;
+ for (ext) |c| switch (state) {
+ .start => switch (c) {
+ '.' => state = .dot,
+ else => return false,
+ },
+ .dot => switch (c) {
+ 'b', 'B' => state = .b,
+ 'c', 'C' => state = .c,
+ 'e', 'E' => state = .e,
+ else => return false,
+ },
+ .b => switch (c) {
+ 'a', 'A' => state = .ba,
+ else => return false,
+ },
+ .c => switch (c) {
+ 'm', 'M' => state = .cm,
+ 'o', 'O' => state = .co,
+ else => return false,
+ },
+ .e => switch (c) {
+ 'x', 'X' => state = .ex,
+ else => return false,
+ },
+ .ba => switch (c) {
+ 't', 'T' => return true, // .BAT
+ else => return false,
+ },
+ .cm => switch (c) {
+ 'd', 'D' => return true, // .CMD
+ else => return false,
+ },
+ .co => switch (c) {
+ 'm', 'M' => return true, // .COM
+ else => return false,
+ },
+ .ex => switch (c) {
+ 'e', 'E' => return true, // .EXE
+ else => return false,
+ },
+ };
+ return false;
+}
+
/// Caller must dealloc.
fn windowsCreateCommandLine(allocator: mem.Allocator, argv: []const []const u8) ![:0]u8 {
var buf = std.ArrayList(u8).init(allocator);
diff --git a/lib/std/os.zig b/lib/std/os.zig
@@ -1944,19 +1944,7 @@ pub fn getenvW(key: [*:0]const u16) ?[:0]const u16 {
while (ptr[i] != 0) : (i += 1) {}
const this_value = ptr[value_start..i :0];
- const key_string_bytes = @intCast(u16, key_slice.len * 2);
- const key_string = windows.UNICODE_STRING{
- .Length = key_string_bytes,
- .MaximumLength = key_string_bytes,
- .Buffer = @intToPtr([*]u16, @ptrToInt(key)),
- };
- const this_key_string_bytes = @intCast(u16, this_key.len * 2);
- const this_key_string = windows.UNICODE_STRING{
- .Length = this_key_string_bytes,
- .MaximumLength = this_key_string_bytes,
- .Buffer = this_key.ptr,
- };
- if (windows.ntdll.RtlEqualUnicodeString(&key_string, &this_key_string, windows.TRUE) == windows.TRUE) {
+ if (windows.eqlIgnoreCaseWTF16(key_slice, this_key)) {
return this_value;
}
diff --git a/lib/std/os/windows.zig b/lib/std/os/windows.zig
@@ -1624,6 +1624,9 @@ pub fn CreateProcessW(
.RING2SEG_MUST_BE_MOVABLE,
.RELOC_CHAIN_XEEDS_SEGLIM,
.INFLOOP_IN_RELOC_CHAIN, // MAX_EXEC_ERROR in errno.cpp
+ // This one is not mapped to ENOEXEC but it is possible, for example
+ // when calling CreateProcessW on a plain text file with a .exe extension
+ .EXE_MACHINE_TYPE_MISMATCH,
=> return error.InvalidExe,
else => |err| return unexpectedError(err),
}
@@ -1824,6 +1827,23 @@ pub fn nanoSecondsToFileTime(ns: i128) FILETIME {
};
}
+/// Compares two WTF16 strings using RtlEqualUnicodeString
+pub fn eqlIgnoreCaseWTF16(a: []const u16, b: []const u16) bool {
+ const a_bytes = @intCast(u16, a.len * 2);
+ const a_string = UNICODE_STRING{
+ .Length = a_bytes,
+ .MaximumLength = a_bytes,
+ .Buffer = @intToPtr([*]u16, @ptrToInt(a.ptr)),
+ };
+ const b_bytes = @intCast(u16, b.len * 2);
+ const b_string = UNICODE_STRING{
+ .Length = b_bytes,
+ .MaximumLength = b_bytes,
+ .Buffer = @intToPtr([*]u16, @ptrToInt(b.ptr)),
+ };
+ return ntdll.RtlEqualUnicodeString(&a_string, &b_string, TRUE) == TRUE;
+}
+
pub const PathSpace = struct {
data: [PATH_MAX_WIDE:0]u16,
len: usize,
@@ -3682,6 +3702,20 @@ pub const RTL_DRIVE_LETTER_CURDIR = extern struct {
pub const PPS_POST_PROCESS_INIT_ROUTINE = ?*const fn () callconv(.C) void;
+pub const FILE_DIRECTORY_INFORMATION = extern struct {
+ NextEntryOffset: ULONG,
+ FileIndex: ULONG,
+ CreationTime: LARGE_INTEGER,
+ LastAccessTime: LARGE_INTEGER,
+ LastWriteTime: LARGE_INTEGER,
+ ChangeTime: LARGE_INTEGER,
+ EndOfFile: LARGE_INTEGER,
+ AllocationSize: LARGE_INTEGER,
+ FileAttributes: ULONG,
+ FileNameLength: ULONG,
+ FileName: [1]WCHAR,
+};
+
pub const FILE_BOTH_DIR_INFORMATION = extern struct {
NextEntryOffset: ULONG,
FileIndex: ULONG,
diff --git a/lib/std/os/windows/kernel32.zig b/lib/std/os/windows/kernel32.zig
@@ -177,6 +177,8 @@ pub extern "kernel32" fn GetEnvironmentStringsW() callconv(WINAPI) ?[*:0]u16;
pub extern "kernel32" fn GetEnvironmentVariableW(lpName: LPWSTR, lpBuffer: [*]u16, nSize: DWORD) callconv(WINAPI) DWORD;
+pub extern "kernel32" fn SetEnvironmentVariableW(lpName: LPCWSTR, lpValue: ?LPCWSTR) callconv(WINAPI) BOOL;
+
pub extern "kernel32" fn GetExitCodeProcess(hProcess: HANDLE, lpExitCode: *DWORD) callconv(WINAPI) BOOL;
pub extern "kernel32" fn GetFileSizeEx(hFile: HANDLE, lpFileSize: *LARGE_INTEGER) callconv(WINAPI) BOOL;
diff --git a/test/standalone.zig b/test/standalone.zig
@@ -63,6 +63,10 @@ pub fn addCases(cases: *tests.StandaloneContext) void {
cases.addBuildFile("test/standalone/load_dynamic_library/build.zig", .{});
}
+ if (builtin.os.tag == .windows) {
+ cases.addBuildFile("test/standalone/windows_spawn/build.zig", .{});
+ }
+
cases.addBuildFile("test/standalone/c_compiler/build.zig", .{
.build_modes = true,
.cross_targets = true,
diff --git a/test/standalone/windows_spawn/build.zig b/test/standalone/windows_spawn/build.zig
@@ -0,0 +1,16 @@
+const Builder = @import("std").build.Builder;
+
+pub fn build(b: *Builder) void {
+ const mode = b.standardReleaseOptions();
+
+ const hello = b.addExecutable("hello", "hello.zig");
+ hello.setBuildMode(mode);
+
+ const main = b.addExecutable("main", "main.zig");
+ main.setBuildMode(mode);
+ const run = main.run();
+ run.addArtifactArg(hello);
+
+ const test_step = b.step("test", "Test it");
+ test_step.dependOn(&run.step);
+}
diff --git a/test/standalone/windows_spawn/hello.zig b/test/standalone/windows_spawn/hello.zig
@@ -0,0 +1,6 @@
+const std = @import("std");
+
+pub fn main() !void {
+ const stdout = std.io.getStdOut().writer();
+ try stdout.writeAll("hello from exe\n");
+}
diff --git a/test/standalone/windows_spawn/main.zig b/test/standalone/windows_spawn/main.zig
@@ -0,0 +1,161 @@
+const std = @import("std");
+const windows = std.os.windows;
+const utf16Literal = std.unicode.utf8ToUtf16LeStringLiteral;
+
+pub fn main() anyerror!void {
+ var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+ defer if (gpa.deinit()) @panic("found memory leaks");
+ const allocator = gpa.allocator();
+
+ var it = try std.process.argsWithAllocator(allocator);
+ defer it.deinit();
+ _ = it.next() orelse unreachable; // skip binary name
+ const hello_exe_cache_path = it.next() orelse unreachable;
+
+ var tmp = std.testing.tmpDir(.{});
+ defer tmp.cleanup();
+
+ const tmp_absolute_path = try tmp.dir.realpathAlloc(allocator, ".");
+ defer allocator.free(tmp_absolute_path);
+ const tmp_absolute_path_w = try std.unicode.utf8ToUtf16LeWithNull(allocator, tmp_absolute_path);
+ defer allocator.free(tmp_absolute_path_w);
+ const cwd_absolute_path = try std.fs.cwd().realpathAlloc(allocator, ".");
+ defer allocator.free(cwd_absolute_path);
+ const tmp_relative_path = try std.fs.path.relative(allocator, cwd_absolute_path, tmp_absolute_path);
+ defer allocator.free(tmp_relative_path);
+
+ // Clear PATH
+ std.debug.assert(std.os.windows.kernel32.SetEnvironmentVariableW(
+ utf16Literal("PATH"),
+ null,
+ ) == windows.TRUE);
+
+ // Set PATHEXT to something predictable
+ std.debug.assert(std.os.windows.kernel32.SetEnvironmentVariableW(
+ utf16Literal("PATHEXT"),
+ utf16Literal(".COM;.EXE;.BAT;.CMD;.JS"),
+ ) == windows.TRUE);
+
+ // No PATH, so it should fail to find anything not in the cwd
+ try testExecError(error.FileNotFound, allocator, "something_missing");
+
+ std.debug.assert(std.os.windows.kernel32.SetEnvironmentVariableW(
+ utf16Literal("PATH"),
+ tmp_absolute_path_w,
+ ) == windows.TRUE);
+
+ // Move hello.exe into the tmp dir which is now added to the path
+ try std.fs.cwd().copyFile(hello_exe_cache_path, tmp.dir, "hello.exe", .{});
+
+ // with extension should find the .exe (case insensitive)
+ try testExec(allocator, "HeLLo.exe", "hello from exe\n");
+ // without extension should find the .exe (case insensitive)
+ try testExec(allocator, "heLLo", "hello from exe\n");
+
+ // now add a .bat
+ try tmp.dir.writeFile("hello.bat", "@echo hello from bat");
+ // and a .cmd
+ try tmp.dir.writeFile("hello.cmd", "@echo hello from cmd");
+
+ // with extension should find the .bat (case insensitive)
+ try testExec(allocator, "heLLo.bat", "hello from bat\r\n");
+ // with extension should find the .cmd (case insensitive)
+ try testExec(allocator, "heLLo.cmd", "hello from cmd\r\n");
+ // without extension should find the .exe (since its first in PATHEXT)
+ try testExec(allocator, "heLLo", "hello from exe\n");
+
+ // now rename the exe to not have an extension
+ try tmp.dir.rename("hello.exe", "hello");
+
+ // with extension should now fail
+ try testExecError(error.FileNotFound, allocator, "hello.exe");
+ // without extension should succeed (case insensitive)
+ try testExec(allocator, "heLLo", "hello from exe\n");
+
+ try tmp.dir.makeDir("something");
+ try tmp.dir.rename("hello", "something/hello.exe");
+
+ const relative_path_no_ext = try std.fs.path.join(allocator, &.{ tmp_relative_path, "something/hello" });
+ defer allocator.free(relative_path_no_ext);
+
+ // Giving a full relative path to something/hello should work
+ try testExec(allocator, relative_path_no_ext, "hello from exe\n");
+ // But commands with path separators get excluded from PATH searching, so this will fail
+ try testExecError(error.FileNotFound, allocator, "something/hello");
+
+ // Now that .BAT is the first PATHEXT that should be found, this should succeed
+ try testExec(allocator, "heLLo", "hello from bat\r\n");
+
+ // Add a hello.exe that is not a valid executable
+ try tmp.dir.writeFile("hello.exe", "invalid");
+
+ // Trying to execute it with extension will give InvalidExe. This is a special
+ // case for .EXE extensions, where if they ever try to get executed but they are
+ // invalid, that gets treated as a fatal error wherever they are found and InvalidExe
+ // is returned immediately.
+ try testExecError(error.InvalidExe, allocator, "hello.exe");
+ // Same thing applies to the command with no extension--even though there is a
+ // hello.bat that could be executed, it should stop after it tries executing
+ // hello.exe and getting InvalidExe.
+ try testExecError(error.InvalidExe, allocator, "hello");
+
+ // If we now rename hello.exe to have no extension, it will behave differently
+ try tmp.dir.rename("hello.exe", "hello");
+
+ // Now, trying to execute it without an extension should treat InvalidExe as recoverable
+ // and skip over it and find hello.bat and execute that
+ try testExec(allocator, "hello", "hello from bat\r\n");
+
+ // If we rename the invalid exe to something else
+ try tmp.dir.rename("hello", "goodbye");
+ // Then we should now get FileNotFound when trying to execute 'goodbye',
+ // since that is what the original error will be after searching for 'goodbye'
+ // in the cwd. It will try to execute 'goodbye' from the PATH but the InvalidExe error
+ // should be ignored in this case.
+ try testExecError(error.FileNotFound, allocator, "goodbye");
+
+ // Now let's set the tmp dir as the cwd and set the path only include the "something" sub dir
+ try tmp.dir.setAsCwd();
+ const something_subdir_abs_path = try std.mem.concatWithSentinel(allocator, u16, &.{ tmp_absolute_path_w, utf16Literal("\\something") }, 0);
+ defer allocator.free(something_subdir_abs_path);
+
+ std.debug.assert(std.os.windows.kernel32.SetEnvironmentVariableW(
+ utf16Literal("PATH"),
+ something_subdir_abs_path,
+ ) == windows.TRUE);
+
+ // Now trying to execute goodbye should give error.InvalidExe since it's the original
+ // error that we got when trying within the cwd
+ try testExecError(error.InvalidExe, allocator, "goodbye");
+
+ // hello should still find the .bat
+ try testExec(allocator, "hello", "hello from bat\r\n");
+
+ // If we rename something/hello.exe to something/goodbye.exe
+ try tmp.dir.rename("something/hello.exe", "something/goodbye.exe");
+ // And try to execute goodbye, then the one in something should be found
+ // since the one in cwd is an invalid executable
+ try testExec(allocator, "goodbye", "hello from exe\n");
+
+ // If we use an absolute path to execute the invalid goodbye
+ const goodbye_abs_path = try std.mem.join(allocator, "\\", &.{ tmp_absolute_path, "goodbye" });
+ defer allocator.free(goodbye_abs_path);
+ // then the PATH should not be searched and we should get InvalidExe
+ try testExecError(error.InvalidExe, allocator, goodbye_abs_path);
+}
+
+fn testExecError(err: anyerror, allocator: std.mem.Allocator, command: []const u8) !void {
+ return std.testing.expectError(err, testExec(allocator, command, ""));
+}
+
+fn testExec(allocator: std.mem.Allocator, command: []const u8, expected_stdout: []const u8) !void {
+ var result = try std.ChildProcess.exec(.{
+ .allocator = allocator,
+ .argv = &[_][]const u8{command},
+ });
+ defer allocator.free(result.stdout);
+ defer allocator.free(result.stderr);
+
+ try std.testing.expectEqualStrings("", result.stderr);
+ try std.testing.expectEqualStrings(expected_stdout, result.stdout);
+}
