imgcat panic when invoked from powershell under WSL paths

glyh commented 7 months ago

What Operating System(s) are you seeing this problem on?

Windows

Which Wayland compositor or X11 Window manager(s) are you using?

The above doesn't apply. I'm on Arch Linux on WSL2 on Windows 11.

Linux mechrevo 5.15.133.1-microsoft-standard-WSL2 #1 SMP Thu Oct 5 21:02:42 UTC 2023 x86_64 GNU/Linux

Windows 11 v22H2(22621.1265).

wezterm is installed on windows 11 while I'm invoking the command via something like wezterm.exe ....

WezTerm version

wezterm 20240129-220340-47f647ca

Did you try the latest nightly build to see if the issue is better (or worse!) than your current version?

Yes, and I updated the version box above to show the version of the nightly that I tried

Describe the bug

Trying to run wezterm.exe imgcat failed.

To Reproduce

Install wezterm.exe and run Arch WSL on it
Start a bash shell in ArchWSL

run

WSLENV=RUST_BACKTRACE/w RUST_BACKTRACE=full wezterm.exe imgcat `wslpath -w your_image_path_here`

failed with this:

09:27:46.757  ERROR  env_bootstrap > panic at wezterm\src\main.rs:377:10 - attempt to divide by zero
   0: <unknown>
   1: <unknown>
   2: <unknown>
   3: git_filter_source_repo
   4: git_filter_source_repo
   5: git_filter_source_repo
   6: git_filter_source_repo
   7: git_credential_username_new
   8: git_credential_username_new
   9: <unknown>
  10: <unknown>
  11: <unknown>
  12: <unknown>
  13: git_filter_source_repo
  14: <unknown>
  15: git_credential_username_new
  16: BaseThreadInitThunk
  17: RtlUserThreadStart

thread 'main' panicked at wezterm\src\main.rs:377:10:
attempt to divide by zero
stack backtrace:
   0:     0x7ff6d8be17d3 - git_filter_source_repo
   1:     0x7ff6d8c09d0d - git_filter_source_repo
   2:     0x7ff6d8bdbac1 - git_filter_source_repo
   3:     0x7ff6d8be15da - git_filter_source_repo
   4:     0x7ff6d8be3e69 - git_filter_source_repo
   5:     0x7ff6d8be3b2b - git_filter_source_repo
   6:     0x7ff6d7ff4620 - <unknown>
   7:     0x7ff6d8be4383 - git_filter_source_repo
   8:     0x7ff6d8be41eb - git_filter_source_repo
   9:     0x7ff6d8be20c9 - git_filter_source_repo
  10:     0x7ff6d8be3f34 - git_filter_source_repo
  11:     0x7ff6d9078297 - git_credential_username_new
  12:     0x7ff6d9078352 - git_credential_username_new
  13:     0x7ff6d7f2a63b - <unknown>
  14:     0x7ff6d7f2c61c - <unknown>
  15:     0x7ff6d7eb9e96 - <unknown>
  16:     0x7ff6d7fc8f1c - <unknown>
  17:     0x7ff6d8bd2a38 - git_filter_source_repo
  18:     0x7ff6d7fc8f08 - <unknown>
  19:     0x7ff6d8fed1cc - git_credential_username_new
  20:     0x7ffaa4c626bd - BaseThreadInitThunk
  21:     0x7ffaa61edfb8 - RtlUserThreadStart

Configuration

-- Pull in the wezterm API
local wezterm = require 'wezterm'

-- This table will hold the configuration.
local config = {}

-- In newer versions of wezterm, use the config_builder which will
-- help provide clearer error messages
if wezterm.config_builder then
  config = wezterm.config_builder()
end

-- This is where you actually apply your config choices

config.default_prog = { 'D:\\Apps\\ArchWSL\\Arch.exe' }

config.font = wezterm.font 'FiraCode Nerd Font'

-- and finally, return the configuration to wezterm
return config

Expected Behavior

No bug, image displayed

Logs

09:28:42.446  ERROR  env_bootstrap > panic at wezterm\src\main.rs:377:10 - attempt to divide by zero
   0: <unknown>
   1: <unknown>
   2: <unknown>
   3: git_filter_source_repo
   4: git_filter_source_repo
   5: git_filter_source_repo
   6: git_filter_source_repo
   7: git_credential_username_new
   8: git_credential_username_new
   9: <unknown>
  10: <unknown>
  11: <unknown>
  12: <unknown>
  13: git_filter_source_repo
  14: <unknown>
  15: git_credential_username_new
  16: BaseThreadInitThunk
  17: RtlUserThreadStart

Anything else?

No response

glyh commented 7 months ago

this does work when I launch powershell from wezterm directly and use imgcat, however.

wez commented 7 months ago

I'm not clear what you're trying here; are you saying that the wezterm.exe imgcat invocation is what is panicking? What are the conditions that cause it to panic? Your summary suggests that it is to do with the path, but it doesn't indicate what the path is. Please provide more information.

glyh commented 7 months ago

I just refined the description. This bug occurs when I run wsl and the default path is a WSL path, running wezterm.exe imgcat it will panic.

In my experiments, switching to powershell from WSL bash and run $env:RUST_BACKTRACE = 'full'; wezterm.exe imgcat someimage.png will also panic. However starting wezterm with powershell directly with wezterm.exe -e "powershell.exe", cd into the windows path and run the command for powershell yields no panic.

TzviPM commented 7 months ago

Just did a bit of debugging myself. It seems that the issue is related to the conpty issue mentioend in https://github.com/wez/wezterm/issues/4029.

When I run wezterm imgcat <img> (with a png file) in WSL, I also get this error. I did a bit of debugging and tracked the issue down to https://github.com/wez/wezterm/blob/c3d37f9edae6951bbb564197a62bb433a289ff4f/wezterm/src/main.rs#L377.

Fixing this issue in general would be interesting, but in my particular case, I don't really care about the cursor. It seems this value is only used when needs_force_cursor_move is true. Would you be open to a PR that calls compute_image_cell_dimensions lazily only when needs_force_cursor_move is true?

If so, I can try running wezterm imgcat --no-move-cursor <img> to see if that avoids the division by zero.

wez commented 7 months ago

Ah yes, this is a duplicate of https://github.com/wez/wezterm/issues/4029 @TzviPM if you'd like to take a stab at resolving this, I'd welcome it. I think there are a couple of things that could be done:

If we get 0 for the cell dimensions, we could either:
- Explain the issue with a nicer error message
- just assume a reasonable default value
Increasing this timeout may prevent this from cropping up as much:

https://github.com/wez/wezterm/blob/767e72a17b46c7fe695b34c592bf0961deddef14/termwiz/src/caps/probed.rs#L154-L163

If you're feeling up to making a PR, I'd rather that you looked at those two things than skirting around the math!

And yes, I would love to see a PR for this: I'm not actively doing dev on Windows recently, and I'm unlikely to have time to do so in the near future.

oalders commented 7 months ago

I can replicate this on macOS running wezterm imgcat inside of tmux. I didn't report previously because I was under the impression that wezterm imgcat was not supported inside of tmux, but I do accidentally do this and the error message surprises me. :smile:

RUST_BACKTRACE=full wezterm imgcat "Bildschirmfoto 2023-12-08 um 3.35.24 PM.png"
09:56:46.758  ERROR  env_bootstrap > panic at wezterm/src/main.rs:383:10 - attempt to divide by zero
   0: backtrace::capture::Backtrace::create
   1: backtrace::capture::Backtrace::new
   2: env_bootstrap::register_panic_hook::{{closure}}
   3: std::panicking::rust_panic_with_hook
   4: std::panicking::begin_panic_handler::{{closure}}
   5: std::sys_common::backtrace::__rust_end_short_backtrace
   6: _rust_begin_unwind
   7: core::panicking::panic_fmt
   8: core::panicking::panic
   9: wezterm::ImgCatCommand::compute_image_cell_dimensions
  10: wezterm::run
  11: wezterm::main
  12: std::sys_common::backtrace::__rust_begin_short_backtrace
  13: std::rt::lang_start::{{closure}}
  14: std::rt::lang_start_internal
  15: std::rt::lang_start
  16: _main

thread 'main' panicked at wezterm/src/main.rs:383:10:
attempt to divide by zero
stack backtrace:
   0:        0x105d4b83c - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h298c9ab285ff3934
   1:        0x105d702c4 - core::fmt::write::h4e276abdb6d0c2a1
   2:        0x105d46fc4 - std::io::Write::write_fmt::hd421848f5f0bf9d0
   3:        0x105d4b678 - std::sys_common::backtrace::print::hd8bd9ecab1f94b94
   4:        0x105d4d1b4 - std::panicking::default_hook::{{closure}}::h520eeb743fc98fb4
   5:        0x105d4cefc - std::panicking::default_hook::ha6550ffe49b63df1
   6:        0x104fbaadc - env_bootstrap::register_panic_hook::{{closure}}::h9b094f72f93dc696
   7:        0x105d4d714 - std::panicking::rust_panic_with_hook::hddb0e884a202de7c
   8:        0x105d4d4b8 - std::panicking::begin_panic_handler::{{closure}}::hd2798398a2fd9077
   9:        0x105d4bca4 - std::sys_common::backtrace::__rust_end_short_backtrace::h9201cc364dbb8a23
  10:        0x105d4d278 - _rust_begin_unwind
  11:        0x105de18b0 - core::panicking::panic_fmt::h4d5168028d4c43c7
  12:        0x105de1924 - core::panicking::panic::h40561ff494e2b577
  13:        0x104f44810 - wezterm::ImgCatCommand::compute_image_cell_dimensions::hf4a654b8b44bc0f5
  14:        0x104f47fd4 - wezterm::run::hdda5256d415fecb7
  15:        0x104f450b4 - wezterm::main::h4e75f015b192b1cc
  16:        0x104ea53dc - std::sys_common::backtrace::__rust_begin_short_backtrace::h2263a45c221c762d
  17:        0x104f9db38 - std::rt::lang_start::{{closure}}::haf77dd2d3edcb4a6
  18:        0x105d3e5dc - std::rt::lang_start_internal::h5b246d44f1526226
  19:        0x104f9db1c - std::rt::lang_start::h9e31e61e00da983c
  20:        0x104f52f2c - _main

Elfahor commented 7 months ago

I'm facing the exact same problem on NixOS, Wayland, tmux. I just installed wezterm; the first run of imgcat worked, and then this.

toolonely commented 6 months ago

this does work when I launch powershell from wezterm directly and use imgcat, however.

I am experiencing similar behavior with another setup: Slackware64-15.0 Linux and WezTerm-20240203-110809-5046fc22-Ubuntu20.04.AppImage

1.

start wezterm
inside it type wezterm imgcat img.png
everything works

2.

start another GUI terminal emulator (I use xfce4-terminal)
inside it type wezterm imgcat img.png
it fails with the backtrace attached above

tomtastic commented 4 months ago

Getting this too, but on : Amazon Linux 2 (loosely Fedora)

❯ wezterm --version
wezterm 20240506-145255-0b50725f
❯ RUST_BACKTRACE=1 http GET 'https://www.tradegate.de/images/charts/intraday/GB00B18S7B29.png?1675672080'
| wezterm imgcat --no-resample --no-move-cursor --hold
13:29:45.466  ERROR  env_bootstrap > panic at wezterm/src/main.rs:383:10 - attempt to divide by zero
   0: env_bootstrap::register_panic_hook::{{closure}}
   1: std::panicking::rust_panic_with_hook
   2: std::panicking::begin_panic_handler::{{closure}}
   3: std::sys_common::backtrace::__rust_end_short_backtrace
   4: rust_begin_unwind
   5: core::panicking::panic_fmt
   6: core::panicking::panic
   7: wezterm::ImgCatCommand::compute_image_cell_dimensions
   8: wezterm::run
   9: wezterm::main
  10: std::sys_common::backtrace::__rust_begin_short_backtrace
  11: std::rt::lang_start::{{closure}}
  12: std::rt::lang_start_internal
  13: main
  14: __libc_start_main
             at /usr/src/debug/glibc-2.26-193-ga0bc5dd3be/csu/../csu/libc-start.c:308
  15: _start

thread 'main' panicked at wezterm/src/main.rs:383:10:
attempt to divide by zero

wez / wezterm