| author |  Carl Åstholm <carl@astholm.se> 2026-02-02 01:24:39+01:00 |
| committer |  Andrew Kelley <andrew@ziglang.org> 2026-04-11 12:25:22-07:00 |
| log | 3223d3a1ac0aa7a5ffb9252c2e8d871f0bf70ec0 |
| tree | b9fc32edffcd5d1673831077f580acd00028e94e |
| parent | 3d482643651285143b555b61c5a6a48db6fc8518 |
Improve debug I/O color detection/handling for WASI and Emscripten
When linking libc, these targets can get their environment variables
from `std.c.environ`. Additionally, it's okay for WASI to use ANSI
escape sequences; nothing in the relevant specs claim otherwise.3 files changed, 16 insertions(+), 11 deletions(-)
lib- std
- process
- start.zig
lib/std/Io/Threaded.zig-7
| ... | ... | @@ -8729,13 +8729,6 @@ fn supportsAnsiEscapeCodes(file: File) Io.Cancelable!bool { |
| 8729 | 8729 | } |
| 8730 | 8730 | } |
| 8731 | 8731 | |
| 8732 | if (native_os == .wasi) { | |
| 8733 | // WASI sanitizes stdout when fd is a tty so ANSI escape codes will not | |
| 8734 | // be interpreted as actual cursor commands, and stderr is always | |
| 8735 | // sanitized. | |
| 8736 | return false; | |
| 8737 | } | |
| 8738 | ||
| 8739 | 8732 | if (try isTty(file)) return true; |
| 8740 | 8733 | |
| 8741 | 8734 | return false; |
lib/std/process/Environ.zig+1-1
| ... | ... | @@ -24,7 +24,7 @@ pub const empty: Environ = .{ .block = .empty }; |
| 24 | 24 | /// operating system `void` is also used. |
| 25 | 25 | pub const Block = switch (native_os) { |
| 26 | 26 | .windows => GlobalBlock, |
| 27 | .wasi => switch (builtin.link_libc) { | |
| 27 | .wasi, .emscripten => switch (builtin.link_libc) { | |
| 28 | 28 | false => GlobalBlock, |
| 29 | 29 | true => PosixBlock, |
| 30 | 30 | }, |
lib/std/start.zig+15-3
| ... | ... | @@ -664,10 +664,22 @@ fn main(c_argc: c_int, c_argv: [*][*:0]c_char, c_envp: [*:null]?[*:0]c_char) cal |
| 664 | 664 | |
| 665 | 665 | fn mainWithoutEnv(c_argc: c_int, c_argv: [*][*:0]c_char) callconv(.c) c_int { |
| 666 | 666 | const argv = @as([*][*:0]u8, @ptrCast(c_argv))[0..@intCast(c_argc)]; |
| 667 | if (@sizeOf(std.Io.Threaded.Argv0) != 0) { | |
| 668 | if (std.Options.debug_threaded_io) |t| t.argv0.value = argv[0]; | |
| 667 | const environ: [:null]?[*:0]u8 = switch (builtin.os.tag) { | |
| 668 | .wasi, .emscripten => environ: { | |
| 669 | const c_environ = std.c.environ; | |
| 670 | var env_count: usize = 0; | |
| 671 | while (c_environ[env_count] != null) : (env_count += 1) {} | |
| 672 | break :environ c_environ[0..env_count :null]; | |
| 673 | }, | |
| 674 | else => &.{}, | |
| 675 | }; | |
| 676 | const env_block: std.process.Environ.Block = .{ .slice = environ }; | |
| 677 | if (std.Options.debug_threaded_io) |t| { | |
| 678 | if (@sizeOf(std.Io.Threaded.Argv0) != 0) t.argv0.value = argv[0]; | |
| 679 | t.environ = .{ .process_environ = .{ .block = env_block } }; | |
| 680 | t.environ_initialized = env_block.isEmpty(); | |
| 669 | 681 | } |
| 670 | return callMain(argv, .empty); | |
| 682 | return callMain(argv, env_block); | |
| 671 | 683 | } |
| 672 | 684 | |
| 673 | 685 | /// General error message for a malformed return type |