mirror of
https://codeberg.org/ziglang/zig.git
synced 2025-12-06 13:54:21 +00:00
ffd071f558
memcpy requires non-overlapping arguments. fifo.realign() handles this case correctly and tries to provide an optimized implementation. This probably wasn't hit in practice, as, in a typical usage, fifo's head is not advanced.
1857 lines
71 KiB
Zig
1857 lines
71 KiB
Zig
const std = @import("../std.zig");
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const builtin = @import("builtin");
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const unicode = std.unicode;
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const fs = std.fs;
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const process = std.process;
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const File = std.fs.File;
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const windows = std.os.windows;
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const linux = std.os.linux;
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const posix = std.posix;
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const mem = std.mem;
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const EnvMap = std.process.EnvMap;
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const maxInt = std.math.maxInt;
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const assert = std.debug.assert;
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const native_os = builtin.os.tag;
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const Allocator = std.mem.Allocator;
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const ChildProcess = @This();
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pub const Id = switch (native_os) {
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.windows => windows.HANDLE,
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.wasi => void,
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else => posix.pid_t,
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};
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/// Available after calling `spawn()`. This becomes `undefined` after calling `wait()`.
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/// On Windows this is the hProcess.
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/// On POSIX this is the pid.
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id: Id,
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thread_handle: if (native_os == .windows) windows.HANDLE else void,
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allocator: mem.Allocator,
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/// The writing end of the child process's standard input pipe.
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/// Usage requires `stdin_behavior == StdIo.Pipe`.
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/// Available after calling `spawn()`.
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stdin: ?File,
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/// The reading end of the child process's standard output pipe.
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/// Usage requires `stdout_behavior == StdIo.Pipe`.
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/// Available after calling `spawn()`.
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stdout: ?File,
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/// The reading end of the child process's standard error pipe.
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/// Usage requires `stderr_behavior == StdIo.Pipe`.
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/// Available after calling `spawn()`.
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stderr: ?File,
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/// Terminated state of the child process.
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/// Available after calling `wait()`.
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term: ?(SpawnError!Term),
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argv: []const []const u8,
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/// Leave as null to use the current env map using the supplied allocator.
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env_map: ?*const EnvMap,
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stdin_behavior: StdIo,
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stdout_behavior: StdIo,
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stderr_behavior: StdIo,
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/// Set to change the user id when spawning the child process.
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uid: if (native_os == .windows or native_os == .wasi) void else ?posix.uid_t,
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/// Set to change the group id when spawning the child process.
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gid: if (native_os == .windows or native_os == .wasi) void else ?posix.gid_t,
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/// Set to change the process group id when spawning the child process.
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pgid: if (native_os == .windows or native_os == .wasi) void else ?posix.pid_t,
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/// Set to change the current working directory when spawning the child process.
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cwd: ?[]const u8,
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/// Set to change the current working directory when spawning the child process.
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/// This is not yet implemented for Windows. See https://github.com/ziglang/zig/issues/5190
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/// Once that is done, `cwd` will be deprecated in favor of this field.
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cwd_dir: ?fs.Dir = null,
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err_pipe: ?if (native_os == .windows) void else [2]posix.fd_t,
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expand_arg0: Arg0Expand,
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/// Darwin-only. Disable ASLR for the child process.
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disable_aslr: bool = false,
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/// Darwin-only. Start child process in suspended state as if SIGSTOP was sent.
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start_suspended: bool = false,
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/// Set to true to obtain rusage information for the child process.
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/// Depending on the target platform and implementation status, the
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/// requested statistics may or may not be available. If they are
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/// available, then the `resource_usage_statistics` field will be populated
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/// after calling `wait`.
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/// On Linux and Darwin, this obtains rusage statistics from wait4().
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request_resource_usage_statistics: bool = false,
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/// This is available after calling wait if
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/// `request_resource_usage_statistics` was set to `true` before calling
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/// `spawn`.
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resource_usage_statistics: ResourceUsageStatistics = .{},
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/// When populated, a pipe will be created for the child process to
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/// communicate progress back to the parent. The file descriptor of the
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/// write end of the pipe will be specified in the `ZIG_PROGRESS`
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/// environment variable inside the child process. The progress reported by
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/// the child will be attached to this progress node in the parent process.
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///
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/// The child's progress tree will be grafted into the parent's progress tree,
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/// by substituting this node with the child's root node.
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progress_node: std.Progress.Node = std.Progress.Node.none,
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pub const ResourceUsageStatistics = struct {
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rusage: @TypeOf(rusage_init) = rusage_init,
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/// Returns the peak resident set size of the child process, in bytes,
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/// if available.
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pub inline fn getMaxRss(rus: ResourceUsageStatistics) ?usize {
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switch (native_os) {
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.linux => {
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if (rus.rusage) |ru| {
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return @as(usize, @intCast(ru.maxrss)) * 1024;
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} else {
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return null;
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}
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},
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.windows => {
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if (rus.rusage) |ru| {
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return ru.PeakWorkingSetSize;
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} else {
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return null;
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}
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},
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.macos, .ios => {
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if (rus.rusage) |ru| {
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// Darwin oddly reports in bytes instead of kilobytes.
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return @as(usize, @intCast(ru.maxrss));
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} else {
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return null;
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}
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},
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else => return null,
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}
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}
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const rusage_init = switch (native_os) {
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.linux, .macos, .ios => @as(?posix.rusage, null),
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.windows => @as(?windows.VM_COUNTERS, null),
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else => {},
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};
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};
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pub const Arg0Expand = posix.Arg0Expand;
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pub const SpawnError = error{
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OutOfMemory,
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/// POSIX-only. `StdIo.Ignore` was selected and opening `/dev/null` returned ENODEV.
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NoDevice,
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/// Windows-only. `cwd` or `argv` was provided and it was invalid WTF-8.
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/// https://simonsapin.github.io/wtf-8/
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InvalidWtf8,
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/// Windows-only. `cwd` was provided, but the path did not exist when spawning the child process.
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CurrentWorkingDirectoryUnlinked,
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/// Windows-only. NUL (U+0000), LF (U+000A), CR (U+000D) are not allowed
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/// within arguments when executing a `.bat`/`.cmd` script.
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/// - NUL/LF signifiies end of arguments, so anything afterwards
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/// would be lost after execution.
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/// - CR is stripped by `cmd.exe`, so any CR codepoints
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/// would be lost after execution.
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InvalidBatchScriptArg,
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} ||
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posix.ExecveError ||
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posix.SetIdError ||
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posix.SetPgidError ||
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posix.ChangeCurDirError ||
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windows.CreateProcessError ||
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windows.GetProcessMemoryInfoError ||
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windows.WaitForSingleObjectError;
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pub const Term = union(enum) {
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Exited: u8,
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Signal: u32,
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Stopped: u32,
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Unknown: u32,
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};
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/// Behavior of the child process's standard input, output, and error
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/// streams.
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pub const StdIo = enum {
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/// Inherit the stream from the parent process.
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Inherit,
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/// Pass a null stream to the child process.
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/// This is /dev/null on POSIX and NUL on Windows.
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Ignore,
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/// Create a pipe for the stream.
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/// The corresponding field (`stdout`, `stderr`, or `stdin`)
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/// will be assigned a `File` object that can be used
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/// to read from or write to the pipe.
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Pipe,
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/// Close the stream after the child process spawns.
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Close,
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};
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/// First argument in argv is the executable.
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pub fn init(argv: []const []const u8, allocator: mem.Allocator) ChildProcess {
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return .{
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.allocator = allocator,
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.argv = argv,
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.id = undefined,
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.thread_handle = undefined,
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.err_pipe = null,
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.term = null,
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.env_map = null,
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.cwd = null,
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.uid = if (native_os == .windows or native_os == .wasi) {} else null,
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.gid = if (native_os == .windows or native_os == .wasi) {} else null,
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.pgid = if (native_os == .windows or native_os == .wasi) {} else null,
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.stdin = null,
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.stdout = null,
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.stderr = null,
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.stdin_behavior = .Inherit,
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.stdout_behavior = .Inherit,
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.stderr_behavior = .Inherit,
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.expand_arg0 = .no_expand,
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};
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}
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pub fn setUserName(self: *ChildProcess, name: []const u8) !void {
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const user_info = try process.getUserInfo(name);
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self.uid = user_info.uid;
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self.gid = user_info.gid;
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}
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/// On success must call `kill` or `wait`.
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/// After spawning the `id` is available.
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pub fn spawn(self: *ChildProcess) SpawnError!void {
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if (!process.can_spawn) {
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@compileError("the target operating system cannot spawn processes");
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}
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if (native_os == .windows) {
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return self.spawnWindows();
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} else {
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return self.spawnPosix();
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}
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}
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pub fn spawnAndWait(self: *ChildProcess) SpawnError!Term {
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try self.spawn();
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return self.wait();
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}
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/// Forcibly terminates child process and then cleans up all resources.
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pub fn kill(self: *ChildProcess) !Term {
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if (native_os == .windows) {
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return self.killWindows(1);
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} else {
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return self.killPosix();
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}
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}
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pub fn killWindows(self: *ChildProcess, exit_code: windows.UINT) !Term {
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if (self.term) |term| {
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self.cleanupStreams();
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return term;
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}
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windows.TerminateProcess(self.id, exit_code) catch |err| switch (err) {
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error.PermissionDenied => {
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// Usually when TerminateProcess triggers a ACCESS_DENIED error, it
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// indicates that the process has already exited, but there may be
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// some rare edge cases where our process handle no longer has the
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// PROCESS_TERMINATE access right, so let's do another check to make
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// sure the process is really no longer running:
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windows.WaitForSingleObjectEx(self.id, 0, false) catch return err;
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return error.AlreadyTerminated;
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},
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else => return err,
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};
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try self.waitUnwrappedWindows();
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return self.term.?;
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}
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pub fn killPosix(self: *ChildProcess) !Term {
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if (self.term) |term| {
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self.cleanupStreams();
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return term;
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}
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posix.kill(self.id, posix.SIG.TERM) catch |err| switch (err) {
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error.ProcessNotFound => return error.AlreadyTerminated,
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else => return err,
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};
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try self.waitUnwrapped();
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return self.term.?;
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}
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/// Blocks until child process terminates and then cleans up all resources.
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pub fn wait(self: *ChildProcess) !Term {
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const term = if (native_os == .windows)
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try self.waitWindows()
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else
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try self.waitPosix();
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self.id = undefined;
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return term;
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}
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pub const RunResult = struct {
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term: Term,
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stdout: []u8,
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stderr: []u8,
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};
|
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fn fifoToOwnedArrayList(fifo: *std.io.PollFifo) std.ArrayList(u8) {
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if (fifo.head != 0) fifo.realign();
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const result = std.ArrayList(u8){
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.items = fifo.buf[0..fifo.count],
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.capacity = fifo.buf.len,
|
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.allocator = fifo.allocator,
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||
};
|
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fifo.* = std.io.PollFifo.init(fifo.allocator);
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return result;
|
||
}
|
||
|
||
/// Collect the output from the process's stdout and stderr. Will return once all output
|
||
/// has been collected. This does not mean that the process has ended. `wait` should still
|
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/// be called to wait for and clean up the process.
|
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///
|
||
/// The process must be started with stdout_behavior and stderr_behavior == .Pipe
|
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pub fn collectOutput(
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child: ChildProcess,
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stdout: *std.ArrayList(u8),
|
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stderr: *std.ArrayList(u8),
|
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max_output_bytes: usize,
|
||
) !void {
|
||
assert(child.stdout_behavior == .Pipe);
|
||
assert(child.stderr_behavior == .Pipe);
|
||
|
||
// we could make this work with multiple allocators but YAGNI
|
||
if (stdout.allocator.ptr != stderr.allocator.ptr or
|
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stdout.allocator.vtable != stderr.allocator.vtable)
|
||
{
|
||
unreachable; // ChildProcess.collectOutput only supports 1 allocator
|
||
}
|
||
|
||
var poller = std.io.poll(stdout.allocator, enum { stdout, stderr }, .{
|
||
.stdout = child.stdout.?,
|
||
.stderr = child.stderr.?,
|
||
});
|
||
defer poller.deinit();
|
||
|
||
while (try poller.poll()) {
|
||
if (poller.fifo(.stdout).count > max_output_bytes)
|
||
return error.StdoutStreamTooLong;
|
||
if (poller.fifo(.stderr).count > max_output_bytes)
|
||
return error.StderrStreamTooLong;
|
||
}
|
||
|
||
stdout.* = fifoToOwnedArrayList(poller.fifo(.stdout));
|
||
stderr.* = fifoToOwnedArrayList(poller.fifo(.stderr));
|
||
}
|
||
|
||
pub const RunError = posix.GetCwdError || posix.ReadError || SpawnError || posix.PollError || error{
|
||
StdoutStreamTooLong,
|
||
StderrStreamTooLong,
|
||
};
|
||
|
||
/// Spawns a child process, waits for it, collecting stdout and stderr, and then returns.
|
||
/// If it succeeds, the caller owns result.stdout and result.stderr memory.
|
||
pub fn run(args: struct {
|
||
allocator: mem.Allocator,
|
||
argv: []const []const u8,
|
||
cwd: ?[]const u8 = null,
|
||
cwd_dir: ?fs.Dir = null,
|
||
env_map: ?*const EnvMap = null,
|
||
max_output_bytes: usize = 50 * 1024,
|
||
expand_arg0: Arg0Expand = .no_expand,
|
||
progress_node: std.Progress.Node = std.Progress.Node.none,
|
||
}) RunError!RunResult {
|
||
var child = ChildProcess.init(args.argv, args.allocator);
|
||
child.stdin_behavior = .Ignore;
|
||
child.stdout_behavior = .Pipe;
|
||
child.stderr_behavior = .Pipe;
|
||
child.cwd = args.cwd;
|
||
child.cwd_dir = args.cwd_dir;
|
||
child.env_map = args.env_map;
|
||
child.expand_arg0 = args.expand_arg0;
|
||
child.progress_node = args.progress_node;
|
||
|
||
var stdout = std.ArrayList(u8).init(args.allocator);
|
||
var stderr = std.ArrayList(u8).init(args.allocator);
|
||
errdefer {
|
||
stdout.deinit();
|
||
stderr.deinit();
|
||
}
|
||
|
||
try child.spawn();
|
||
try child.collectOutput(&stdout, &stderr, args.max_output_bytes);
|
||
|
||
return RunResult{
|
||
.term = try child.wait(),
|
||
.stdout = try stdout.toOwnedSlice(),
|
||
.stderr = try stderr.toOwnedSlice(),
|
||
};
|
||
}
|
||
|
||
fn waitWindows(self: *ChildProcess) !Term {
|
||
if (self.term) |term| {
|
||
self.cleanupStreams();
|
||
return term;
|
||
}
|
||
|
||
try self.waitUnwrappedWindows();
|
||
return self.term.?;
|
||
}
|
||
|
||
fn waitPosix(self: *ChildProcess) !Term {
|
||
if (self.term) |term| {
|
||
self.cleanupStreams();
|
||
return term;
|
||
}
|
||
|
||
try self.waitUnwrapped();
|
||
return self.term.?;
|
||
}
|
||
|
||
fn waitUnwrappedWindows(self: *ChildProcess) !void {
|
||
const result = windows.WaitForSingleObjectEx(self.id, windows.INFINITE, false);
|
||
|
||
self.term = @as(SpawnError!Term, x: {
|
||
var exit_code: windows.DWORD = undefined;
|
||
if (windows.kernel32.GetExitCodeProcess(self.id, &exit_code) == 0) {
|
||
break :x Term{ .Unknown = 0 };
|
||
} else {
|
||
break :x Term{ .Exited = @as(u8, @truncate(exit_code)) };
|
||
}
|
||
});
|
||
|
||
if (self.request_resource_usage_statistics) {
|
||
self.resource_usage_statistics.rusage = try windows.GetProcessMemoryInfo(self.id);
|
||
}
|
||
|
||
posix.close(self.id);
|
||
posix.close(self.thread_handle);
|
||
self.cleanupStreams();
|
||
return result;
|
||
}
|
||
|
||
fn waitUnwrapped(self: *ChildProcess) !void {
|
||
const res: posix.WaitPidResult = res: {
|
||
if (self.request_resource_usage_statistics) {
|
||
switch (native_os) {
|
||
.linux, .macos, .ios => {
|
||
var ru: posix.rusage = undefined;
|
||
const res = posix.wait4(self.id, 0, &ru);
|
||
self.resource_usage_statistics.rusage = ru;
|
||
break :res res;
|
||
},
|
||
else => {},
|
||
}
|
||
}
|
||
|
||
break :res posix.waitpid(self.id, 0);
|
||
};
|
||
const status = res.status;
|
||
self.cleanupStreams();
|
||
self.handleWaitResult(status);
|
||
}
|
||
|
||
fn handleWaitResult(self: *ChildProcess, status: u32) void {
|
||
self.term = self.cleanupAfterWait(status);
|
||
}
|
||
|
||
fn cleanupStreams(self: *ChildProcess) void {
|
||
if (self.stdin) |*stdin| {
|
||
stdin.close();
|
||
self.stdin = null;
|
||
}
|
||
if (self.stdout) |*stdout| {
|
||
stdout.close();
|
||
self.stdout = null;
|
||
}
|
||
if (self.stderr) |*stderr| {
|
||
stderr.close();
|
||
self.stderr = null;
|
||
}
|
||
}
|
||
|
||
fn cleanupAfterWait(self: *ChildProcess, status: u32) !Term {
|
||
if (self.err_pipe) |err_pipe| {
|
||
defer destroyPipe(err_pipe);
|
||
|
||
if (native_os == .linux) {
|
||
var fd = [1]posix.pollfd{posix.pollfd{
|
||
.fd = err_pipe[0],
|
||
.events = posix.POLL.IN,
|
||
.revents = undefined,
|
||
}};
|
||
|
||
// Check if the eventfd buffer stores a non-zero value by polling
|
||
// it, that's the error code returned by the child process.
|
||
_ = posix.poll(&fd, 0) catch unreachable;
|
||
|
||
// According to eventfd(2) the descriptor is readable if the counter
|
||
// has a value greater than 0
|
||
if ((fd[0].revents & posix.POLL.IN) != 0) {
|
||
const err_int = try readIntFd(err_pipe[0]);
|
||
return @as(SpawnError, @errorCast(@errorFromInt(err_int)));
|
||
}
|
||
} else {
|
||
// Write maxInt(ErrInt) to the write end of the err_pipe. This is after
|
||
// waitpid, so this write is guaranteed to be after the child
|
||
// pid potentially wrote an error. This way we can do a blocking
|
||
// read on the error pipe and either get maxInt(ErrInt) (no error) or
|
||
// an error code.
|
||
try writeIntFd(err_pipe[1], maxInt(ErrInt));
|
||
const err_int = try readIntFd(err_pipe[0]);
|
||
// Here we potentially return the fork child's error from the parent
|
||
// pid.
|
||
if (err_int != maxInt(ErrInt)) {
|
||
return @as(SpawnError, @errorCast(@errorFromInt(err_int)));
|
||
}
|
||
}
|
||
}
|
||
|
||
return statusToTerm(status);
|
||
}
|
||
|
||
fn statusToTerm(status: u32) Term {
|
||
return if (posix.W.IFEXITED(status))
|
||
Term{ .Exited = posix.W.EXITSTATUS(status) }
|
||
else if (posix.W.IFSIGNALED(status))
|
||
Term{ .Signal = posix.W.TERMSIG(status) }
|
||
else if (posix.W.IFSTOPPED(status))
|
||
Term{ .Stopped = posix.W.STOPSIG(status) }
|
||
else
|
||
Term{ .Unknown = status };
|
||
}
|
||
|
||
fn spawnPosix(self: *ChildProcess) SpawnError!void {
|
||
// The child process does need to access (one end of) these pipes. However,
|
||
// we must initially set CLOEXEC to avoid a race condition. If another thread
|
||
// is racing to spawn a different child process, we don't want it to inherit
|
||
// these FDs in any scenario; that would mean that, for instance, calls to
|
||
// `poll` from the parent would not report the child's stdout as closing when
|
||
// expected, since the other child may retain a reference to the write end of
|
||
// the pipe. So, we create the pipes with CLOEXEC initially. After fork, we
|
||
// need to do something in the new child to make sure we preserve the reference
|
||
// we want. We could use `fcntl` to remove CLOEXEC from the FD, but as it
|
||
// turns out, we `dup2` everything anyway, so there's no need!
|
||
const pipe_flags: posix.O = .{ .CLOEXEC = true };
|
||
|
||
const stdin_pipe = if (self.stdin_behavior == .Pipe) try posix.pipe2(pipe_flags) else undefined;
|
||
errdefer if (self.stdin_behavior == .Pipe) {
|
||
destroyPipe(stdin_pipe);
|
||
};
|
||
|
||
const stdout_pipe = if (self.stdout_behavior == .Pipe) try posix.pipe2(pipe_flags) else undefined;
|
||
errdefer if (self.stdout_behavior == .Pipe) {
|
||
destroyPipe(stdout_pipe);
|
||
};
|
||
|
||
const stderr_pipe = if (self.stderr_behavior == .Pipe) try posix.pipe2(pipe_flags) else undefined;
|
||
errdefer if (self.stderr_behavior == .Pipe) {
|
||
destroyPipe(stderr_pipe);
|
||
};
|
||
|
||
const any_ignore = (self.stdin_behavior == .Ignore or self.stdout_behavior == .Ignore or self.stderr_behavior == .Ignore);
|
||
const dev_null_fd = if (any_ignore)
|
||
posix.openZ("/dev/null", .{ .ACCMODE = .RDWR }, 0) catch |err| switch (err) {
|
||
error.PathAlreadyExists => unreachable,
|
||
error.NoSpaceLeft => unreachable,
|
||
error.FileTooBig => unreachable,
|
||
error.DeviceBusy => unreachable,
|
||
error.FileLocksNotSupported => unreachable,
|
||
error.BadPathName => unreachable, // Windows-only
|
||
error.WouldBlock => unreachable,
|
||
error.NetworkNotFound => unreachable, // Windows-only
|
||
else => |e| return e,
|
||
}
|
||
else
|
||
undefined;
|
||
defer {
|
||
if (any_ignore) posix.close(dev_null_fd);
|
||
}
|
||
|
||
const prog_pipe: [2]posix.fd_t = p: {
|
||
if (self.progress_node.index == .none) {
|
||
break :p .{ -1, -1 };
|
||
} else {
|
||
// We use CLOEXEC for the same reason as in `pipe_flags`.
|
||
break :p try posix.pipe2(.{ .NONBLOCK = true, .CLOEXEC = true });
|
||
}
|
||
};
|
||
errdefer destroyPipe(prog_pipe);
|
||
|
||
var arena_allocator = std.heap.ArenaAllocator.init(self.allocator);
|
||
defer arena_allocator.deinit();
|
||
const arena = arena_allocator.allocator();
|
||
|
||
// The POSIX standard does not allow malloc() between fork() and execve(),
|
||
// and `self.allocator` may be a libc allocator.
|
||
// I have personally observed the child process deadlocking when it tries
|
||
// to call malloc() due to a heap allocation between fork() and execve(),
|
||
// in musl v1.1.24.
|
||
// Additionally, we want to reduce the number of possible ways things
|
||
// can fail between fork() and execve().
|
||
// Therefore, we do all the allocation for the execve() before the fork().
|
||
// This means we must do the null-termination of argv and env vars here.
|
||
const argv_buf = try arena.allocSentinel(?[*:0]const u8, self.argv.len, null);
|
||
for (self.argv, 0..) |arg, i| argv_buf[i] = (try arena.dupeZ(u8, arg)).ptr;
|
||
|
||
const prog_fileno = 3;
|
||
comptime assert(@max(posix.STDIN_FILENO, posix.STDOUT_FILENO, posix.STDERR_FILENO) + 1 == prog_fileno);
|
||
|
||
const envp: [*:null]const ?[*:0]const u8 = m: {
|
||
const prog_fd: i32 = if (prog_pipe[1] == -1) -1 else prog_fileno;
|
||
if (self.env_map) |env_map| {
|
||
break :m (try process.createEnvironFromMap(arena, env_map, .{
|
||
.zig_progress_fd = prog_fd,
|
||
})).ptr;
|
||
} else if (builtin.link_libc) {
|
||
break :m (try process.createEnvironFromExisting(arena, std.c.environ, .{
|
||
.zig_progress_fd = prog_fd,
|
||
})).ptr;
|
||
} else if (builtin.output_mode == .Exe) {
|
||
// Then we have Zig start code and this works.
|
||
// TODO type-safety for null-termination of `os.environ`.
|
||
break :m (try process.createEnvironFromExisting(arena, @ptrCast(std.os.environ.ptr), .{
|
||
.zig_progress_fd = prog_fd,
|
||
})).ptr;
|
||
} else {
|
||
// TODO come up with a solution for this.
|
||
@compileError("missing std lib enhancement: ChildProcess implementation has no way to collect the environment variables to forward to the child process");
|
||
}
|
||
};
|
||
|
||
// This pipe is used to communicate errors between the time of fork
|
||
// and execve from the child process to the parent process.
|
||
const err_pipe = blk: {
|
||
if (native_os == .linux) {
|
||
const fd = try posix.eventfd(0, linux.EFD.CLOEXEC);
|
||
// There's no distinction between the readable and the writeable
|
||
// end with eventfd
|
||
break :blk [2]posix.fd_t{ fd, fd };
|
||
} else {
|
||
break :blk try posix.pipe2(.{ .CLOEXEC = true });
|
||
}
|
||
};
|
||
errdefer destroyPipe(err_pipe);
|
||
|
||
const pid_result = try posix.fork();
|
||
if (pid_result == 0) {
|
||
// we are the child
|
||
setUpChildIo(self.stdin_behavior, stdin_pipe[0], posix.STDIN_FILENO, dev_null_fd) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
setUpChildIo(self.stdout_behavior, stdout_pipe[1], posix.STDOUT_FILENO, dev_null_fd) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
setUpChildIo(self.stderr_behavior, stderr_pipe[1], posix.STDERR_FILENO, dev_null_fd) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
|
||
if (self.cwd_dir) |cwd| {
|
||
posix.fchdir(cwd.fd) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
} else if (self.cwd) |cwd| {
|
||
posix.chdir(cwd) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
}
|
||
|
||
// Must happen after fchdir above, the cwd file descriptor might be
|
||
// equal to prog_fileno and be clobbered by this dup2 call.
|
||
if (prog_pipe[1] != -1) posix.dup2(prog_pipe[1], prog_fileno) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
|
||
if (self.gid) |gid| {
|
||
posix.setregid(gid, gid) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
}
|
||
|
||
if (self.uid) |uid| {
|
||
posix.setreuid(uid, uid) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
}
|
||
|
||
if (self.pgid) |pid| {
|
||
posix.setpgid(0, pid) catch |err| forkChildErrReport(err_pipe[1], err);
|
||
}
|
||
|
||
const err = switch (self.expand_arg0) {
|
||
.expand => posix.execvpeZ_expandArg0(.expand, argv_buf.ptr[0].?, argv_buf.ptr, envp),
|
||
.no_expand => posix.execvpeZ_expandArg0(.no_expand, argv_buf.ptr[0].?, argv_buf.ptr, envp),
|
||
};
|
||
forkChildErrReport(err_pipe[1], err);
|
||
}
|
||
|
||
// we are the parent
|
||
const pid: i32 = @intCast(pid_result);
|
||
if (self.stdin_behavior == .Pipe) {
|
||
self.stdin = .{ .handle = stdin_pipe[1] };
|
||
} else {
|
||
self.stdin = null;
|
||
}
|
||
if (self.stdout_behavior == .Pipe) {
|
||
self.stdout = .{ .handle = stdout_pipe[0] };
|
||
} else {
|
||
self.stdout = null;
|
||
}
|
||
if (self.stderr_behavior == .Pipe) {
|
||
self.stderr = .{ .handle = stderr_pipe[0] };
|
||
} else {
|
||
self.stderr = null;
|
||
}
|
||
|
||
self.id = pid;
|
||
self.err_pipe = err_pipe;
|
||
self.term = null;
|
||
|
||
if (self.stdin_behavior == .Pipe) {
|
||
posix.close(stdin_pipe[0]);
|
||
}
|
||
if (self.stdout_behavior == .Pipe) {
|
||
posix.close(stdout_pipe[1]);
|
||
}
|
||
if (self.stderr_behavior == .Pipe) {
|
||
posix.close(stderr_pipe[1]);
|
||
}
|
||
|
||
if (prog_pipe[1] != -1) {
|
||
posix.close(prog_pipe[1]);
|
||
}
|
||
self.progress_node.setIpcFd(prog_pipe[0]);
|
||
}
|
||
|
||
fn spawnWindows(self: *ChildProcess) SpawnError!void {
|
||
var saAttr = windows.SECURITY_ATTRIBUTES{
|
||
.nLength = @sizeOf(windows.SECURITY_ATTRIBUTES),
|
||
.bInheritHandle = windows.TRUE,
|
||
.lpSecurityDescriptor = null,
|
||
};
|
||
|
||
const any_ignore = (self.stdin_behavior == StdIo.Ignore or self.stdout_behavior == StdIo.Ignore or self.stderr_behavior == StdIo.Ignore);
|
||
|
||
const nul_handle = if (any_ignore)
|
||
// "\Device\Null" or "\??\NUL"
|
||
windows.OpenFile(&[_]u16{ '\\', 'D', 'e', 'v', 'i', 'c', 'e', '\\', 'N', 'u', 'l', 'l' }, .{
|
||
.access_mask = windows.GENERIC_READ | windows.GENERIC_WRITE | windows.SYNCHRONIZE,
|
||
.share_access = windows.FILE_SHARE_READ | windows.FILE_SHARE_WRITE | windows.FILE_SHARE_DELETE,
|
||
.sa = &saAttr,
|
||
.creation = windows.OPEN_EXISTING,
|
||
}) catch |err| switch (err) {
|
||
error.PathAlreadyExists => return error.Unexpected, // not possible for "NUL"
|
||
error.PipeBusy => return error.Unexpected, // not possible for "NUL"
|
||
error.FileNotFound => return error.Unexpected, // not possible for "NUL"
|
||
error.AccessDenied => return error.Unexpected, // not possible for "NUL"
|
||
error.NameTooLong => return error.Unexpected, // not possible for "NUL"
|
||
error.WouldBlock => return error.Unexpected, // not possible for "NUL"
|
||
error.NetworkNotFound => return error.Unexpected, // not possible for "NUL"
|
||
error.AntivirusInterference => return error.Unexpected, // not possible for "NUL"
|
||
else => |e| return e,
|
||
}
|
||
else
|
||
undefined;
|
||
defer {
|
||
if (any_ignore) posix.close(nul_handle);
|
||
}
|
||
|
||
var g_hChildStd_IN_Rd: ?windows.HANDLE = null;
|
||
var g_hChildStd_IN_Wr: ?windows.HANDLE = null;
|
||
switch (self.stdin_behavior) {
|
||
StdIo.Pipe => {
|
||
try windowsMakePipeIn(&g_hChildStd_IN_Rd, &g_hChildStd_IN_Wr, &saAttr);
|
||
},
|
||
StdIo.Ignore => {
|
||
g_hChildStd_IN_Rd = nul_handle;
|
||
},
|
||
StdIo.Inherit => {
|
||
g_hChildStd_IN_Rd = windows.GetStdHandle(windows.STD_INPUT_HANDLE) catch null;
|
||
},
|
||
StdIo.Close => {
|
||
g_hChildStd_IN_Rd = null;
|
||
},
|
||
}
|
||
errdefer if (self.stdin_behavior == StdIo.Pipe) {
|
||
windowsDestroyPipe(g_hChildStd_IN_Rd, g_hChildStd_IN_Wr);
|
||
};
|
||
|
||
var g_hChildStd_OUT_Rd: ?windows.HANDLE = null;
|
||
var g_hChildStd_OUT_Wr: ?windows.HANDLE = null;
|
||
switch (self.stdout_behavior) {
|
||
StdIo.Pipe => {
|
||
try windowsMakeAsyncPipe(&g_hChildStd_OUT_Rd, &g_hChildStd_OUT_Wr, &saAttr);
|
||
},
|
||
StdIo.Ignore => {
|
||
g_hChildStd_OUT_Wr = nul_handle;
|
||
},
|
||
StdIo.Inherit => {
|
||
g_hChildStd_OUT_Wr = windows.GetStdHandle(windows.STD_OUTPUT_HANDLE) catch null;
|
||
},
|
||
StdIo.Close => {
|
||
g_hChildStd_OUT_Wr = null;
|
||
},
|
||
}
|
||
errdefer if (self.stdout_behavior == StdIo.Pipe) {
|
||
windowsDestroyPipe(g_hChildStd_OUT_Rd, g_hChildStd_OUT_Wr);
|
||
};
|
||
|
||
var g_hChildStd_ERR_Rd: ?windows.HANDLE = null;
|
||
var g_hChildStd_ERR_Wr: ?windows.HANDLE = null;
|
||
switch (self.stderr_behavior) {
|
||
StdIo.Pipe => {
|
||
try windowsMakeAsyncPipe(&g_hChildStd_ERR_Rd, &g_hChildStd_ERR_Wr, &saAttr);
|
||
},
|
||
StdIo.Ignore => {
|
||
g_hChildStd_ERR_Wr = nul_handle;
|
||
},
|
||
StdIo.Inherit => {
|
||
g_hChildStd_ERR_Wr = windows.GetStdHandle(windows.STD_ERROR_HANDLE) catch null;
|
||
},
|
||
StdIo.Close => {
|
||
g_hChildStd_ERR_Wr = null;
|
||
},
|
||
}
|
||
errdefer if (self.stderr_behavior == StdIo.Pipe) {
|
||
windowsDestroyPipe(g_hChildStd_ERR_Rd, g_hChildStd_ERR_Wr);
|
||
};
|
||
|
||
var siStartInfo = windows.STARTUPINFOW{
|
||
.cb = @sizeOf(windows.STARTUPINFOW),
|
||
.hStdError = g_hChildStd_ERR_Wr,
|
||
.hStdOutput = g_hChildStd_OUT_Wr,
|
||
.hStdInput = g_hChildStd_IN_Rd,
|
||
.dwFlags = windows.STARTF_USESTDHANDLES,
|
||
|
||
.lpReserved = null,
|
||
.lpDesktop = null,
|
||
.lpTitle = null,
|
||
.dwX = 0,
|
||
.dwY = 0,
|
||
.dwXSize = 0,
|
||
.dwYSize = 0,
|
||
.dwXCountChars = 0,
|
||
.dwYCountChars = 0,
|
||
.dwFillAttribute = 0,
|
||
.wShowWindow = 0,
|
||
.cbReserved2 = 0,
|
||
.lpReserved2 = null,
|
||
};
|
||
var piProcInfo: windows.PROCESS_INFORMATION = undefined;
|
||
|
||
const cwd_w = if (self.cwd) |cwd| try unicode.wtf8ToWtf16LeAllocZ(self.allocator, cwd) else null;
|
||
defer if (cwd_w) |cwd| self.allocator.free(cwd);
|
||
const cwd_w_ptr = if (cwd_w) |cwd| cwd.ptr else null;
|
||
|
||
const maybe_envp_buf = if (self.env_map) |env_map| try process.createWindowsEnvBlock(self.allocator, env_map) else null;
|
||
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_wtf8 = self.argv[0];
|
||
const app_name_is_absolute = fs.path.isAbsolute(app_name_wtf8);
|
||
|
||
// the cwd set in ChildProcess is in effect when choosing the executable path
|
||
// to match posix semantics
|
||
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_wtf8).?;
|
||
break :x try unicode.wtf8ToWtf16LeAllocZ(self.allocator, dir);
|
||
} else if (self.cwd) |cwd| {
|
||
cwd_path_w_needs_free = true;
|
||
break :x try unicode.wtf8ToWtf16LeAllocZ(self.allocator, cwd);
|
||
} else {
|
||
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_wtf8 = fs.path.basename(app_name_wtf8);
|
||
// 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_wtf8 = if (!app_name_is_absolute) fs.path.dirname(app_name_wtf8) else null;
|
||
const app_dirname_w: ?[:0]u16 = x: {
|
||
if (maybe_app_dirname_wtf8) |app_dirname_wtf8| {
|
||
break :x try unicode.wtf8ToWtf16LeAllocZ(self.allocator, app_dirname_wtf8);
|
||
}
|
||
break :x null;
|
||
};
|
||
defer if (app_dirname_w != null) self.allocator.free(app_dirname_w.?);
|
||
|
||
const app_name_w = try unicode.wtf8ToWtf16LeAllocZ(self.allocator, app_basename_wtf8);
|
||
defer self.allocator.free(app_name_w);
|
||
|
||
run: {
|
||
const PATH: [:0]const u16 = process.getenvW(unicode.utf8ToUtf16LeStringLiteral("PATH")) orelse &[_:0]u16{};
|
||
const PATHEXT: [:0]const u16 = process.getenvW(unicode.utf8ToUtf16LeStringLiteral("PATHEXT")) orelse &[_:0]u16{};
|
||
|
||
// In case the command ends up being a .bat/.cmd script, we need to escape things using the cmd.exe rules
|
||
// and invoke cmd.exe ourselves in order to mitigate arbitrary command execution from maliciously
|
||
// constructed arguments.
|
||
//
|
||
// We'll need to wait until we're actually trying to run the command to know for sure
|
||
// if the resolved command has the `.bat` or `.cmd` extension, so we defer actually
|
||
// serializing the command line until we determine how it should be serialized.
|
||
var cmd_line_cache = WindowsCommandLineCache.init(self.allocator, self.argv);
|
||
defer cmd_line_cache.deinit();
|
||
|
||
var app_buf: std.ArrayListUnmanaged(u16) = .empty;
|
||
defer app_buf.deinit(self.allocator);
|
||
|
||
try app_buf.appendSlice(self.allocator, app_name_w);
|
||
|
||
var dir_buf: std.ArrayListUnmanaged(u16) = .empty;
|
||
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_cache, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo) catch |no_path_err| {
|
||
const original_err = switch (no_path_err) {
|
||
// argv[0] contains unsupported characters that will never resolve to a valid exe.
|
||
error.InvalidArg0 => return error.FileNotFound,
|
||
error.FileNotFound, error.InvalidExe, error.AccessDenied => |e| e,
|
||
error.UnrecoverableInvalidExe => return error.InvalidExe,
|
||
else => |e| return e,
|
||
};
|
||
|
||
// If the app name had path separators, that disallows PATH searching,
|
||
// and there's no need to search the PATH if the app name is absolute.
|
||
// We still search the path if the cwd is absolute because of the
|
||
// "cwd set in ChildProcess is in effect when choosing the executable path
|
||
// to match posix semantics" behavior--we don't want to skip searching
|
||
// the PATH just because we were trying to set the cwd of the child process.
|
||
if (app_dirname_w != null or app_name_is_absolute) {
|
||
return original_err;
|
||
}
|
||
|
||
var it = mem.tokenizeScalar(u16, PATH, ';');
|
||
while (it.next()) |search_path| {
|
||
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_cache, envp_ptr, cwd_w_ptr, &siStartInfo, &piProcInfo)) {
|
||
break :run;
|
||
} else |err| switch (err) {
|
||
// argv[0] contains unsupported characters that will never resolve to a valid exe.
|
||
error.InvalidArg0 => return error.FileNotFound,
|
||
error.FileNotFound, error.AccessDenied, error.InvalidExe => continue,
|
||
error.UnrecoverableInvalidExe => return error.InvalidExe,
|
||
else => |e| return e,
|
||
}
|
||
} else {
|
||
return original_err;
|
||
}
|
||
};
|
||
}
|
||
|
||
if (g_hChildStd_IN_Wr) |h| {
|
||
self.stdin = File{ .handle = h };
|
||
} else {
|
||
self.stdin = null;
|
||
}
|
||
if (g_hChildStd_OUT_Rd) |h| {
|
||
self.stdout = File{ .handle = h };
|
||
} else {
|
||
self.stdout = null;
|
||
}
|
||
if (g_hChildStd_ERR_Rd) |h| {
|
||
self.stderr = File{ .handle = h };
|
||
} else {
|
||
self.stderr = null;
|
||
}
|
||
|
||
self.id = piProcInfo.hProcess;
|
||
self.thread_handle = piProcInfo.hThread;
|
||
self.term = null;
|
||
|
||
if (self.stdin_behavior == StdIo.Pipe) {
|
||
posix.close(g_hChildStd_IN_Rd.?);
|
||
}
|
||
if (self.stderr_behavior == StdIo.Pipe) {
|
||
posix.close(g_hChildStd_ERR_Wr.?);
|
||
}
|
||
if (self.stdout_behavior == StdIo.Pipe) {
|
||
posix.close(g_hChildStd_OUT_Wr.?);
|
||
}
|
||
}
|
||
|
||
fn setUpChildIo(stdio: StdIo, pipe_fd: i32, std_fileno: i32, dev_null_fd: i32) !void {
|
||
switch (stdio) {
|
||
.Pipe => try posix.dup2(pipe_fd, std_fileno),
|
||
.Close => posix.close(std_fileno),
|
||
.Inherit => {},
|
||
.Ignore => try posix.dup2(dev_null_fd, std_fileno),
|
||
}
|
||
}
|
||
|
||
fn destroyPipe(pipe: [2]posix.fd_t) void {
|
||
if (pipe[0] != -1) posix.close(pipe[0]);
|
||
if (pipe[0] != pipe[1]) posix.close(pipe[1]);
|
||
}
|
||
|
||
// Child of fork calls this to report an error to the fork parent.
|
||
// Then the child exits.
|
||
fn forkChildErrReport(fd: i32, err: ChildProcess.SpawnError) noreturn {
|
||
writeIntFd(fd, @as(ErrInt, @intFromError(err))) catch {};
|
||
// If we're linking libc, some naughty applications may have registered atexit handlers
|
||
// which we really do not want to run in the fork child. I caught LLVM doing this and
|
||
// it caused a deadlock instead of doing an exit syscall. In the words of Avril Lavigne,
|
||
// "Why'd you have to go and make things so complicated?"
|
||
if (builtin.link_libc) {
|
||
// The _exit(2) function does nothing but make the exit syscall, unlike exit(3)
|
||
std.c._exit(1);
|
||
}
|
||
posix.exit(1);
|
||
}
|
||
|
||
fn writeIntFd(fd: i32, value: ErrInt) !void {
|
||
const file: File = .{ .handle = fd };
|
||
file.writer().writeInt(u64, @intCast(value), .little) catch return error.SystemResources;
|
||
}
|
||
|
||
fn readIntFd(fd: i32) !ErrInt {
|
||
const file: File = .{ .handle = fd };
|
||
return @intCast(file.reader().readInt(u64, .little) catch return error.SystemResources);
|
||
}
|
||
|
||
const ErrInt = std.meta.Int(.unsigned, @sizeOf(anyerror) * 8);
|
||
|
||
/// 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_cache: *WindowsCommandLineCache,
|
||
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 iterate the matches and take note of any that are either the unappended version,
|
||
// or a version with a supported PATHEXT appended. We then try calling CreateProcessW
|
||
// with the found versions in the appropriate order.
|
||
|
||
var dir = dir: {
|
||
// needs to be null-terminated
|
||
try dir_buf.append(allocator, 0);
|
||
defer dir_buf.shrinkRetainingCapacity(dir_path_len);
|
||
const dir_path_z = dir_buf.items[0 .. dir_buf.items.len - 1 :0];
|
||
const prefixed_path = try windows.wToPrefixedFileW(null, dir_path_z);
|
||
break :dir fs.cwd().openDirW(prefixed_path.span().ptr, .{ .iterate = 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];
|
||
|
||
// This 2048 is arbitrary, we just want it to be large enough to get multiple FILE_DIRECTORY_INFORMATION entries
|
||
// returned per NtQueryDirectoryFile call.
|
||
var file_information_buf: [2048]u8 align(@alignOf(windows.FILE_DIRECTORY_INFORMATION)) = undefined;
|
||
const file_info_maximum_single_entry_size = @sizeOf(windows.FILE_DIRECTORY_INFORMATION) + (windows.NAME_MAX * 2);
|
||
if (file_information_buf.len < file_info_maximum_single_entry_size) {
|
||
@compileError("file_information_buf must be large enough to contain at least one maximum size FILE_DIRECTORY_INFORMATION entry");
|
||
}
|
||
var io_status: windows.IO_STATUS_BLOCK = undefined;
|
||
|
||
const num_supported_pathext = @typeInfo(WindowsExtension).@"enum".fields.len;
|
||
var pathext_seen = [_]bool{false} ** num_supported_pathext;
|
||
var any_pathext_seen = false;
|
||
var unappended_exists = false;
|
||
|
||
// Fully iterate the wildcard matches via NtQueryDirectoryFile and take note of all versions
|
||
// of the app_name we should try to spawn.
|
||
// Note: This is necessary because the order of the files returned is filesystem-dependent:
|
||
// On NTFS, `blah.exe*` will always return `blah.exe` first if it exists.
|
||
// On FAT32, it's possible for something like `blah.exe.obj` to be returned first.
|
||
while (true) {
|
||
const app_name_len_bytes = std.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 = @constCast(app_name_wildcard.ptr),
|
||
};
|
||
const rc = windows.ntdll.NtQueryDirectoryFile(
|
||
dir.fd,
|
||
null,
|
||
null,
|
||
null,
|
||
&io_status,
|
||
&file_information_buf,
|
||
file_information_buf.len,
|
||
.FileDirectoryInformation,
|
||
windows.FALSE, // single result
|
||
&app_name_unicode_string,
|
||
windows.FALSE, // 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 => break,
|
||
.ACCESS_DENIED => return error.AccessDenied,
|
||
else => return windows.unexpectedStatus(rc),
|
||
}
|
||
|
||
// According to the docs, this can only happen if there is not enough room in the
|
||
// buffer to write at least one complete FILE_DIRECTORY_INFORMATION entry.
|
||
// Therefore, this condition should not be possible to hit with the buffer size we use.
|
||
std.debug.assert(io_status.Information != 0);
|
||
|
||
var it = windows.FileInformationIterator(windows.FILE_DIRECTORY_INFORMATION){ .buf = &file_information_buf };
|
||
while (it.next()) |info| {
|
||
// Skip directories
|
||
if (info.FileAttributes & windows.FILE_ATTRIBUTE_DIRECTORY != 0) continue;
|
||
const filename = @as([*]u16, @ptrCast(&info.FileName))[0 .. info.FileNameLength / 2];
|
||
// Because all results start with the app_name since we're using the wildcard `app_name*`,
|
||
// if the length is equal to app_name then this is an exact match
|
||
if (filename.len == app_name_len) {
|
||
// Note: We can't break early here because it's possible that the unappended version
|
||
// fails to spawn, in which case we still want to try the PATHEXT appended versions.
|
||
unappended_exists = true;
|
||
} else if (windowsCreateProcessSupportsExtension(filename[app_name_len..])) |pathext_ext| {
|
||
pathext_seen[@intFromEnum(pathext_ext)] = true;
|
||
any_pathext_seen = true;
|
||
}
|
||
}
|
||
}
|
||
|
||
const unappended_err = unappended: {
|
||
if (unappended_exists) {
|
||
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];
|
||
|
||
const is_bat_or_cmd = bat_or_cmd: {
|
||
const app_name = app_buf.items[0..app_name_len];
|
||
const ext_start = std.mem.lastIndexOfScalar(u16, app_name, '.') orelse break :bat_or_cmd false;
|
||
const ext = app_name[ext_start..];
|
||
const ext_enum = windowsCreateProcessSupportsExtension(ext) orelse break :bat_or_cmd false;
|
||
switch (ext_enum) {
|
||
.cmd, .bat => break :bat_or_cmd true,
|
||
else => break :bat_or_cmd false,
|
||
}
|
||
};
|
||
const cmd_line_w = if (is_bat_or_cmd)
|
||
try cmd_line_cache.scriptCommandLine(full_app_name)
|
||
else
|
||
try cmd_line_cache.commandLine();
|
||
const app_name_w = if (is_bat_or_cmd)
|
||
try cmd_line_cache.cmdExePath()
|
||
else
|
||
full_app_name;
|
||
|
||
if (windowsCreateProcess(app_name_w.ptr, cmd_line_w.ptr, 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;
|
||
};
|
||
|
||
if (!any_pathext_seen) return unappended_err;
|
||
|
||
// Now try any PATHEXT appended versions that we've seen
|
||
var ext_it = mem.tokenizeScalar(u16, pathext, ';');
|
||
while (ext_it.next()) |ext| {
|
||
const ext_enum = windowsCreateProcessSupportsExtension(ext) orelse continue;
|
||
if (!pathext_seen[@intFromEnum(ext_enum)]) 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];
|
||
|
||
const is_bat_or_cmd = switch (ext_enum) {
|
||
.cmd, .bat => true,
|
||
else => false,
|
||
};
|
||
const cmd_line_w = if (is_bat_or_cmd)
|
||
try cmd_line_cache.scriptCommandLine(full_app_name)
|
||
else
|
||
try cmd_line_cache.commandLine();
|
||
const app_name_w = if (is_bat_or_cmd)
|
||
try cmd_line_cache.cmdExePath()
|
||
else
|
||
full_app_name;
|
||
|
||
if (windowsCreateProcess(app_name_w.ptr, cmd_line_w.ptr, 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
|
||
// > is NULL, the new process uses the environment of the calling process.
|
||
// > ...
|
||
// > An environment block can contain either Unicode or ANSI characters. If
|
||
// > the environment block pointed to by lpEnvironment contains Unicode
|
||
// > characters, be sure that dwCreationFlags includes CREATE_UNICODE_ENVIRONMENT.
|
||
// > If this parameter is NULL and the environment block of the parent process
|
||
// > contains Unicode characters, you must also ensure that dwCreationFlags
|
||
// > includes CREATE_UNICODE_ENVIRONMENT.
|
||
// This seems to imply that we have to somehow know whether our process parent passed
|
||
// CREATE_UNICODE_ENVIRONMENT if we want to pass NULL for the environment parameter.
|
||
// Since we do not know this information that would imply that we must not pass NULL
|
||
// for the parameter.
|
||
// However this would imply that programs compiled with -DUNICODE could not pass
|
||
// environment variables to programs that were not, which seems unlikely.
|
||
// More investigation is needed.
|
||
return windows.CreateProcessW(
|
||
app_name,
|
||
cmd_line,
|
||
null,
|
||
null,
|
||
windows.TRUE,
|
||
windows.CREATE_UNICODE_ENVIRONMENT,
|
||
@as(?*anyopaque, @ptrCast(envp_ptr)),
|
||
cwd_ptr,
|
||
lpStartupInfo,
|
||
lpProcessInformation,
|
||
);
|
||
}
|
||
|
||
fn windowsMakePipeIn(rd: *?windows.HANDLE, wr: *?windows.HANDLE, sattr: *const windows.SECURITY_ATTRIBUTES) !void {
|
||
var rd_h: windows.HANDLE = undefined;
|
||
var wr_h: windows.HANDLE = undefined;
|
||
try windows.CreatePipe(&rd_h, &wr_h, sattr);
|
||
errdefer windowsDestroyPipe(rd_h, wr_h);
|
||
try windows.SetHandleInformation(wr_h, windows.HANDLE_FLAG_INHERIT, 0);
|
||
rd.* = rd_h;
|
||
wr.* = wr_h;
|
||
}
|
||
|
||
fn windowsDestroyPipe(rd: ?windows.HANDLE, wr: ?windows.HANDLE) void {
|
||
if (rd) |h| posix.close(h);
|
||
if (wr) |h| posix.close(h);
|
||
}
|
||
|
||
fn windowsMakeAsyncPipe(rd: *?windows.HANDLE, wr: *?windows.HANDLE, sattr: *const windows.SECURITY_ATTRIBUTES) !void {
|
||
var tmp_bufw: [128]u16 = undefined;
|
||
|
||
// Anonymous pipes are built upon Named pipes.
|
||
// https://docs.microsoft.com/en-us/windows/win32/api/namedpipeapi/nf-namedpipeapi-createpipe
|
||
// Asynchronous (overlapped) read and write operations are not supported by anonymous pipes.
|
||
// https://docs.microsoft.com/en-us/windows/win32/ipc/anonymous-pipe-operations
|
||
const pipe_path = blk: {
|
||
var tmp_buf: [128]u8 = undefined;
|
||
// Forge a random path for the pipe.
|
||
const pipe_path = std.fmt.bufPrintZ(
|
||
&tmp_buf,
|
||
"\\\\.\\pipe\\zig-childprocess-{d}-{d}",
|
||
.{ windows.GetCurrentProcessId(), pipe_name_counter.fetchAdd(1, .monotonic) },
|
||
) catch unreachable;
|
||
const len = std.unicode.wtf8ToWtf16Le(&tmp_bufw, pipe_path) catch unreachable;
|
||
tmp_bufw[len] = 0;
|
||
break :blk tmp_bufw[0..len :0];
|
||
};
|
||
|
||
// Create the read handle that can be used with overlapped IO ops.
|
||
const read_handle = windows.kernel32.CreateNamedPipeW(
|
||
pipe_path.ptr,
|
||
windows.PIPE_ACCESS_INBOUND | windows.FILE_FLAG_OVERLAPPED,
|
||
windows.PIPE_TYPE_BYTE,
|
||
1,
|
||
4096,
|
||
4096,
|
||
0,
|
||
sattr,
|
||
);
|
||
if (read_handle == windows.INVALID_HANDLE_VALUE) {
|
||
switch (windows.GetLastError()) {
|
||
else => |err| return windows.unexpectedError(err),
|
||
}
|
||
}
|
||
errdefer posix.close(read_handle);
|
||
|
||
var sattr_copy = sattr.*;
|
||
const write_handle = windows.kernel32.CreateFileW(
|
||
pipe_path.ptr,
|
||
windows.GENERIC_WRITE,
|
||
0,
|
||
&sattr_copy,
|
||
windows.OPEN_EXISTING,
|
||
windows.FILE_ATTRIBUTE_NORMAL,
|
||
null,
|
||
);
|
||
if (write_handle == windows.INVALID_HANDLE_VALUE) {
|
||
switch (windows.GetLastError()) {
|
||
else => |err| return windows.unexpectedError(err),
|
||
}
|
||
}
|
||
errdefer posix.close(write_handle);
|
||
|
||
try windows.SetHandleInformation(read_handle, windows.HANDLE_FLAG_INHERIT, 0);
|
||
|
||
rd.* = read_handle;
|
||
wr.* = write_handle;
|
||
}
|
||
|
||
var pipe_name_counter = std.atomic.Value(u32).init(1);
|
||
|
||
/// File name extensions supported natively by `CreateProcess()` on Windows.
|
||
// Should be kept in sync with `windowsCreateProcessSupportsExtension`.
|
||
pub const WindowsExtension = enum {
|
||
bat,
|
||
cmd,
|
||
com,
|
||
exe,
|
||
};
|
||
|
||
/// Case-insensitive WTF-16 lookup
|
||
fn windowsCreateProcessSupportsExtension(ext: []const u16) ?WindowsExtension {
|
||
if (ext.len != 4) return null;
|
||
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 null,
|
||
},
|
||
.dot => switch (c) {
|
||
'b', 'B' => state = .b,
|
||
'c', 'C' => state = .c,
|
||
'e', 'E' => state = .e,
|
||
else => return null,
|
||
},
|
||
.b => switch (c) {
|
||
'a', 'A' => state = .ba,
|
||
else => return null,
|
||
},
|
||
.c => switch (c) {
|
||
'm', 'M' => state = .cm,
|
||
'o', 'O' => state = .co,
|
||
else => return null,
|
||
},
|
||
.e => switch (c) {
|
||
'x', 'X' => state = .ex,
|
||
else => return null,
|
||
},
|
||
.ba => switch (c) {
|
||
't', 'T' => return .bat,
|
||
else => return null,
|
||
},
|
||
.cm => switch (c) {
|
||
'd', 'D' => return .cmd,
|
||
else => return null,
|
||
},
|
||
.co => switch (c) {
|
||
'm', 'M' => return .com,
|
||
else => return null,
|
||
},
|
||
.ex => switch (c) {
|
||
'e', 'E' => return .exe,
|
||
else => return null,
|
||
},
|
||
};
|
||
return null;
|
||
}
|
||
|
||
test windowsCreateProcessSupportsExtension {
|
||
try std.testing.expectEqual(WindowsExtension.exe, windowsCreateProcessSupportsExtension(&[_]u16{ '.', 'e', 'X', 'e' }).?);
|
||
try std.testing.expect(windowsCreateProcessSupportsExtension(&[_]u16{ '.', 'e', 'X', 'e', 'c' }) == null);
|
||
}
|
||
|
||
/// Serializes argv into a WTF-16 encoded command-line string for use with CreateProcessW.
|
||
///
|
||
/// Serialization is done on-demand and the result is cached in order to allow for:
|
||
/// - Only serializing the particular type of command line needed (`.bat`/`.cmd`
|
||
/// command line serialization is different from `.exe`/etc)
|
||
/// - Reusing the serialized command lines if necessary (i.e. if the execution
|
||
/// of a command fails and the PATH is going to be continued to be searched
|
||
/// for more candidates)
|
||
const WindowsCommandLineCache = struct {
|
||
cmd_line: ?[:0]u16 = null,
|
||
script_cmd_line: ?[:0]u16 = null,
|
||
cmd_exe_path: ?[:0]u16 = null,
|
||
argv: []const []const u8,
|
||
allocator: mem.Allocator,
|
||
|
||
fn init(allocator: mem.Allocator, argv: []const []const u8) WindowsCommandLineCache {
|
||
return .{
|
||
.allocator = allocator,
|
||
.argv = argv,
|
||
};
|
||
}
|
||
|
||
fn deinit(self: *WindowsCommandLineCache) void {
|
||
if (self.cmd_line) |cmd_line| self.allocator.free(cmd_line);
|
||
if (self.script_cmd_line) |script_cmd_line| self.allocator.free(script_cmd_line);
|
||
if (self.cmd_exe_path) |cmd_exe_path| self.allocator.free(cmd_exe_path);
|
||
}
|
||
|
||
fn commandLine(self: *WindowsCommandLineCache) ![:0]u16 {
|
||
if (self.cmd_line == null) {
|
||
self.cmd_line = try argvToCommandLineWindows(self.allocator, self.argv);
|
||
}
|
||
return self.cmd_line.?;
|
||
}
|
||
|
||
/// Not cached, since the path to the batch script will change during PATH searching.
|
||
/// `script_path` should be as qualified as possible, e.g. if the PATH is being searched,
|
||
/// then script_path should include both the search path and the script filename
|
||
/// (this allows avoiding cmd.exe having to search the PATH again).
|
||
fn scriptCommandLine(self: *WindowsCommandLineCache, script_path: []const u16) ![:0]u16 {
|
||
if (self.script_cmd_line) |v| self.allocator.free(v);
|
||
self.script_cmd_line = try argvToScriptCommandLineWindows(
|
||
self.allocator,
|
||
script_path,
|
||
self.argv[1..],
|
||
);
|
||
return self.script_cmd_line.?;
|
||
}
|
||
|
||
fn cmdExePath(self: *WindowsCommandLineCache) ![:0]u16 {
|
||
if (self.cmd_exe_path == null) {
|
||
self.cmd_exe_path = try windowsCmdExePath(self.allocator);
|
||
}
|
||
return self.cmd_exe_path.?;
|
||
}
|
||
};
|
||
|
||
/// Returns the absolute path of `cmd.exe` within the Windows system directory.
|
||
/// The caller owns the returned slice.
|
||
fn windowsCmdExePath(allocator: mem.Allocator) error{ OutOfMemory, Unexpected }![:0]u16 {
|
||
var buf = try std.ArrayListUnmanaged(u16).initCapacity(allocator, 128);
|
||
errdefer buf.deinit(allocator);
|
||
while (true) {
|
||
const unused_slice = buf.unusedCapacitySlice();
|
||
// TODO: Get the system directory from PEB.ReadOnlyStaticServerData
|
||
const len = windows.kernel32.GetSystemDirectoryW(@ptrCast(unused_slice), @intCast(unused_slice.len));
|
||
if (len == 0) {
|
||
switch (windows.GetLastError()) {
|
||
else => |err| return windows.unexpectedError(err),
|
||
}
|
||
}
|
||
if (len > unused_slice.len) {
|
||
try buf.ensureUnusedCapacity(allocator, len);
|
||
} else {
|
||
buf.items.len = len;
|
||
break;
|
||
}
|
||
}
|
||
switch (buf.items[buf.items.len - 1]) {
|
||
'/', '\\' => {},
|
||
else => try buf.append(allocator, fs.path.sep),
|
||
}
|
||
try buf.appendSlice(allocator, unicode.utf8ToUtf16LeStringLiteral("cmd.exe"));
|
||
return try buf.toOwnedSliceSentinel(allocator, 0);
|
||
}
|
||
|
||
const ArgvToCommandLineError = error{ OutOfMemory, InvalidWtf8, InvalidArg0 };
|
||
|
||
/// Serializes `argv` to a Windows command-line string suitable for passing to a child process and
|
||
/// parsing by the `CommandLineToArgvW` algorithm. The caller owns the returned slice.
|
||
///
|
||
/// To avoid arbitrary command execution, this function should not be used when spawning `.bat`/`.cmd` scripts.
|
||
/// https://flatt.tech/research/posts/batbadbut-you-cant-securely-execute-commands-on-windows/
|
||
///
|
||
/// When executing `.bat`/`.cmd` scripts, use `argvToScriptCommandLineWindows` instead.
|
||
fn argvToCommandLineWindows(
|
||
allocator: mem.Allocator,
|
||
argv: []const []const u8,
|
||
) ArgvToCommandLineError![:0]u16 {
|
||
var buf = std.ArrayList(u8).init(allocator);
|
||
defer buf.deinit();
|
||
|
||
if (argv.len != 0) {
|
||
const arg0 = argv[0];
|
||
|
||
// The first argument must be quoted if it contains spaces or ASCII control characters
|
||
// (excluding DEL). It also follows special quoting rules where backslashes have no special
|
||
// interpretation, which makes it impossible to pass certain first arguments containing
|
||
// double quotes to a child process without characters from the first argument leaking into
|
||
// subsequent ones (which could have security implications).
|
||
//
|
||
// Empty arguments technically don't need quotes, but we quote them anyway for maximum
|
||
// compatibility with different implementations of the 'CommandLineToArgvW' algorithm.
|
||
//
|
||
// Double quotes are illegal in paths on Windows, so for the sake of simplicity we reject
|
||
// all first arguments containing double quotes, even ones that we could theoretically
|
||
// serialize in unquoted form.
|
||
var needs_quotes = arg0.len == 0;
|
||
for (arg0) |c| {
|
||
if (c <= ' ') {
|
||
needs_quotes = true;
|
||
} else if (c == '"') {
|
||
return error.InvalidArg0;
|
||
}
|
||
}
|
||
if (needs_quotes) {
|
||
try buf.append('"');
|
||
try buf.appendSlice(arg0);
|
||
try buf.append('"');
|
||
} else {
|
||
try buf.appendSlice(arg0);
|
||
}
|
||
|
||
for (argv[1..]) |arg| {
|
||
try buf.append(' ');
|
||
|
||
// Subsequent arguments must be quoted if they contain spaces, tabs or double quotes,
|
||
// or if they are empty. For simplicity and for maximum compatibility with different
|
||
// implementations of the 'CommandLineToArgvW' algorithm, we also quote all ASCII
|
||
// control characters (again, excluding DEL).
|
||
needs_quotes = for (arg) |c| {
|
||
if (c <= ' ' or c == '"') {
|
||
break true;
|
||
}
|
||
} else arg.len == 0;
|
||
if (!needs_quotes) {
|
||
try buf.appendSlice(arg);
|
||
continue;
|
||
}
|
||
|
||
try buf.append('"');
|
||
var backslash_count: usize = 0;
|
||
for (arg) |byte| {
|
||
switch (byte) {
|
||
'\\' => {
|
||
backslash_count += 1;
|
||
},
|
||
'"' => {
|
||
try buf.appendNTimes('\\', backslash_count * 2 + 1);
|
||
try buf.append('"');
|
||
backslash_count = 0;
|
||
},
|
||
else => {
|
||
try buf.appendNTimes('\\', backslash_count);
|
||
try buf.append(byte);
|
||
backslash_count = 0;
|
||
},
|
||
}
|
||
}
|
||
try buf.appendNTimes('\\', backslash_count * 2);
|
||
try buf.append('"');
|
||
}
|
||
}
|
||
|
||
return try unicode.wtf8ToWtf16LeAllocZ(allocator, buf.items);
|
||
}
|
||
|
||
test argvToCommandLineWindows {
|
||
const t = testArgvToCommandLineWindows;
|
||
|
||
try t(&.{
|
||
\\C:\Program Files\zig\zig.exe
|
||
,
|
||
\\run
|
||
,
|
||
\\.\src\main.zig
|
||
,
|
||
\\-target
|
||
,
|
||
\\x86_64-windows-gnu
|
||
,
|
||
\\-O
|
||
,
|
||
\\ReleaseSafe
|
||
,
|
||
\\--
|
||
,
|
||
\\--emoji=🗿
|
||
,
|
||
\\--eval=new Regex("Dwayne \"The Rock\" Johnson")
|
||
,
|
||
},
|
||
\\"C:\Program Files\zig\zig.exe" run .\src\main.zig -target x86_64-windows-gnu -O ReleaseSafe -- --emoji=🗿 "--eval=new Regex(\"Dwayne \\\"The Rock\\\" Johnson\")"
|
||
);
|
||
|
||
try t(&.{}, "");
|
||
try t(&.{""}, "\"\"");
|
||
try t(&.{" "}, "\" \"");
|
||
try t(&.{"\t"}, "\"\t\"");
|
||
try t(&.{"\x07"}, "\"\x07\"");
|
||
try t(&.{"🦎"}, "🦎");
|
||
|
||
try t(
|
||
&.{ "zig", "aa aa", "bb\tbb", "cc\ncc", "dd\r\ndd", "ee\x7Fee" },
|
||
"zig \"aa aa\" \"bb\tbb\" \"cc\ncc\" \"dd\r\ndd\" ee\x7Fee",
|
||
);
|
||
|
||
try t(
|
||
&.{ "\\\\foo bar\\foo bar\\", "\\\\zig zag\\zig zag\\" },
|
||
"\"\\\\foo bar\\foo bar\\\" \"\\\\zig zag\\zig zag\\\\\"",
|
||
);
|
||
|
||
try std.testing.expectError(
|
||
error.InvalidArg0,
|
||
argvToCommandLineWindows(std.testing.allocator, &.{"\"quotes\"quotes\""}),
|
||
);
|
||
try std.testing.expectError(
|
||
error.InvalidArg0,
|
||
argvToCommandLineWindows(std.testing.allocator, &.{"quotes\"quotes"}),
|
||
);
|
||
try std.testing.expectError(
|
||
error.InvalidArg0,
|
||
argvToCommandLineWindows(std.testing.allocator, &.{"q u o t e s \" q u o t e s"}),
|
||
);
|
||
}
|
||
|
||
fn testArgvToCommandLineWindows(argv: []const []const u8, expected_cmd_line: []const u8) !void {
|
||
const cmd_line_w = try argvToCommandLineWindows(std.testing.allocator, argv);
|
||
defer std.testing.allocator.free(cmd_line_w);
|
||
|
||
const cmd_line = try unicode.wtf16LeToWtf8Alloc(std.testing.allocator, cmd_line_w);
|
||
defer std.testing.allocator.free(cmd_line);
|
||
|
||
try std.testing.expectEqualStrings(expected_cmd_line, cmd_line);
|
||
}
|
||
|
||
const ArgvToScriptCommandLineError = error{
|
||
OutOfMemory,
|
||
InvalidWtf8,
|
||
/// NUL (U+0000), LF (U+000A), CR (U+000D) are not allowed
|
||
/// within arguments when executing a `.bat`/`.cmd` script.
|
||
/// - NUL/LF signifiies end of arguments, so anything afterwards
|
||
/// would be lost after execution.
|
||
/// - CR is stripped by `cmd.exe`, so any CR codepoints
|
||
/// would be lost after execution.
|
||
InvalidBatchScriptArg,
|
||
};
|
||
|
||
/// Serializes `argv` to a Windows command-line string that uses `cmd.exe /c` and `cmd.exe`-specific
|
||
/// escaping rules. The caller owns the returned slice.
|
||
///
|
||
/// Escapes `argv` using the suggested mitigation against arbitrary command execution from:
|
||
/// https://flatt.tech/research/posts/batbadbut-you-cant-securely-execute-commands-on-windows/
|
||
///
|
||
/// The return of this function will look like
|
||
/// `cmd.exe /d /e:ON /v:OFF /c "<escaped command line>"`
|
||
/// and should be used as the `lpCommandLine` of `CreateProcessW`, while the
|
||
/// return of `windowsCmdExePath` should be used as `lpApplicationName`.
|
||
///
|
||
/// Should only be used when spawning `.bat`/`.cmd` scripts, see `argvToCommandLineWindows` otherwise.
|
||
/// The `.bat`/`.cmd` file must be known to both have the `.bat`/`.cmd` extension and exist on the filesystem.
|
||
fn argvToScriptCommandLineWindows(
|
||
allocator: mem.Allocator,
|
||
/// Path to the `.bat`/`.cmd` script. If this path is relative, it is assumed to be relative to the CWD.
|
||
/// The script must have been verified to exist at this path before calling this function.
|
||
script_path: []const u16,
|
||
/// Arguments, not including the script name itself. Expected to be encoded as WTF-8.
|
||
script_args: []const []const u8,
|
||
) ArgvToScriptCommandLineError![:0]u16 {
|
||
var buf = try std.ArrayList(u8).initCapacity(allocator, 64);
|
||
defer buf.deinit();
|
||
|
||
// `/d` disables execution of AutoRun commands.
|
||
// `/e:ON` and `/v:OFF` are needed for BatBadBut mitigation:
|
||
// > If delayed expansion is enabled via the registry value DelayedExpansion,
|
||
// > it must be disabled by explicitly calling cmd.exe with the /V:OFF option.
|
||
// > Escaping for % requires the command extension to be enabled.
|
||
// > If it’s disabled via the registry value EnableExtensions, it must be enabled with the /E:ON option.
|
||
// https://flatt.tech/research/posts/batbadbut-you-cant-securely-execute-commands-on-windows/
|
||
buf.appendSliceAssumeCapacity("cmd.exe /d /e:ON /v:OFF /c \"");
|
||
|
||
// Always quote the path to the script arg
|
||
buf.appendAssumeCapacity('"');
|
||
// We always want the path to the batch script to include a path separator in order to
|
||
// avoid cmd.exe searching the PATH for the script. This is not part of the arbitrary
|
||
// command execution mitigation, we just know exactly what script we want to execute
|
||
// at this point, and potentially making cmd.exe re-find it is unnecessary.
|
||
//
|
||
// If the script path does not have a path separator, then we know its relative to CWD and
|
||
// we can just put `.\` in the front.
|
||
if (mem.indexOfAny(u16, script_path, &[_]u16{ mem.nativeToLittle(u16, '\\'), mem.nativeToLittle(u16, '/') }) == null) {
|
||
try buf.appendSlice(".\\");
|
||
}
|
||
// Note that we don't do any escaping/mitigations for this argument, since the relevant
|
||
// characters (", %, etc) are illegal in file paths and this function should only be called
|
||
// with script paths that have been verified to exist.
|
||
try unicode.wtf16LeToWtf8ArrayList(&buf, script_path);
|
||
buf.appendAssumeCapacity('"');
|
||
|
||
for (script_args) |arg| {
|
||
// Literal carriage returns get stripped when run through cmd.exe
|
||
// and NUL/newlines act as 'end of command.' Because of this, it's basically
|
||
// always a mistake to include these characters in argv, so it's
|
||
// an error condition in order to ensure that the return of this
|
||
// function can always roundtrip through cmd.exe.
|
||
if (std.mem.indexOfAny(u8, arg, "\x00\r\n") != null) {
|
||
return error.InvalidBatchScriptArg;
|
||
}
|
||
|
||
// Separate args with a space.
|
||
try buf.append(' ');
|
||
|
||
// Need to quote if the argument is empty (otherwise the arg would just be lost)
|
||
// or if the last character is a `\`, since then something like "%~2" in a .bat
|
||
// script would cause the closing " to be escaped which we don't want.
|
||
var needs_quotes = arg.len == 0 or arg[arg.len - 1] == '\\';
|
||
if (!needs_quotes) {
|
||
for (arg) |c| {
|
||
switch (c) {
|
||
// Known good characters that don't need to be quoted
|
||
'A'...'Z', 'a'...'z', '0'...'9', '#', '$', '*', '+', '-', '.', '/', ':', '?', '@', '\\', '_' => {},
|
||
// When in doubt, quote
|
||
else => {
|
||
needs_quotes = true;
|
||
break;
|
||
},
|
||
}
|
||
}
|
||
}
|
||
if (needs_quotes) {
|
||
try buf.append('"');
|
||
}
|
||
var backslashes: usize = 0;
|
||
for (arg) |c| {
|
||
switch (c) {
|
||
'\\' => {
|
||
backslashes += 1;
|
||
},
|
||
'"' => {
|
||
try buf.appendNTimes('\\', backslashes);
|
||
try buf.append('"');
|
||
backslashes = 0;
|
||
},
|
||
// Replace `%` with `%%cd:~,%`.
|
||
//
|
||
// cmd.exe allows extracting a substring from an environment
|
||
// variable with the syntax: `%foo:~<start_index>,<end_index>%`.
|
||
// Therefore, `%cd:~,%` will always expand to an empty string
|
||
// since both the start and end index are blank, and it is assumed
|
||
// that `%cd%` is always available since it is a built-in variable
|
||
// that corresponds to the current directory.
|
||
//
|
||
// This means that replacing `%foo%` with `%%cd:~,%foo%%cd:~,%`
|
||
// will stop `%foo%` from being expanded and *after* expansion
|
||
// we'll still be left with `%foo%` (the literal string).
|
||
'%' => {
|
||
// the trailing `%` is appended outside the switch
|
||
try buf.appendSlice("%%cd:~,");
|
||
backslashes = 0;
|
||
},
|
||
else => {
|
||
backslashes = 0;
|
||
},
|
||
}
|
||
try buf.append(c);
|
||
}
|
||
if (needs_quotes) {
|
||
try buf.appendNTimes('\\', backslashes);
|
||
try buf.append('"');
|
||
}
|
||
}
|
||
|
||
try buf.append('"');
|
||
|
||
return try unicode.wtf8ToWtf16LeAllocZ(allocator, buf.items);
|
||
}
|