mirror of
https://github.com/fish-shell/fish-shell.git
synced 2024-11-26 10:43:47 +08:00
Use RAII for restoring term modes
In particular, this allows restoring the terminal on crashes, which is feasible now that we have the panic handler. Since std::process::exit() skips destructors, we need to reshuffle some code. The "exit_without_destructors" semantics (which std::process::exit() als has) was mostly necessary for C++ since Rust leaks global variables by default.
This commit is contained in:
parent
3cfa09d1bd
commit
1216801474
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@ -27,10 +27,9 @@ use fish::{
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BUILTIN_ERR_MISSING, BUILTIN_ERR_UNKNOWN, STATUS_CMD_OK, STATUS_CMD_UNKNOWN,
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},
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common::{
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escape, exit_without_destructors, get_executable_path,
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restore_term_foreground_process_group_for_exit, save_term_foreground_process_group,
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scoped_push_replacer, str2wcstring, wcs2string, PACKAGE_NAME, PROFILING_ACTIVE,
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PROGRAM_NAME,
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escape, get_executable_path, restore_term_foreground_process_group_for_exit,
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save_term_foreground_process_group, scoped_push_replacer, str2wcstring, wcs2string,
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ScopeGuard, PACKAGE_NAME, PROFILING_ACTIVE, PROGRAM_NAME,
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},
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env::{
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environment::{env_init, EnvStack, Environment},
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@ -54,14 +53,13 @@ use fish::{
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get_login, is_interactive_session, mark_login, mark_no_exec, proc_init,
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set_interactive_session,
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},
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reader::{reader_init, reader_read, restore_term_mode, term_copy_modes},
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reader::{reader_init, reader_read, term_copy_modes},
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signal::{signal_clear_cancel, signal_unblock_all},
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threads::{self, asan_maybe_exit},
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threads::{self},
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topic_monitor,
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wchar::prelude::*,
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wutil::waccess,
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};
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use std::env;
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use std::ffi::{CString, OsStr, OsString};
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use std::fs::File;
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use std::mem::MaybeUninit;
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@ -69,6 +67,7 @@ use std::os::unix::prelude::*;
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use std::path::{Path, PathBuf};
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use std::sync::atomic::Ordering;
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use std::sync::Arc;
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use std::{env, ops::ControlFlow};
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const DOC_DIR: &str = env!("DOCDIR");
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const DATA_DIR: &str = env!("DATADIR");
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@ -313,7 +312,7 @@ fn run_command_list(parser: &Parser, cmds: &[OsString]) -> i32 {
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retval.unwrap()
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}
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fn fish_parse_opt(args: &mut [WString], opts: &mut FishCmdOpts) -> usize {
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fn fish_parse_opt(args: &mut [WString], opts: &mut FishCmdOpts) -> ControlFlow<i32, usize> {
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use fish::wgetopt::{wgetopter_t, wopt, woption, woption_argument_t::*};
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const RUSAGE_ARG: char = 1 as char;
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@ -394,7 +393,7 @@ fn fish_parse_opt(args: &mut [WString], opts: &mut FishCmdOpts) -> usize {
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// this is left-justified
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println!("{:<width$} {}", cat.name, desc, width = name_width);
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}
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std::process::exit(0);
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return ControlFlow::Break(0);
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}
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// "--profile" - this does not activate profiling right away,
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// rather it's done after startup is finished.
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@ -411,7 +410,7 @@ fn fish_parse_opt(args: &mut [WString], opts: &mut FishCmdOpts) -> usize {
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"%s",
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wgettext_fmt!("%s, version %s\n", PACKAGE_NAME, fish::BUILD_VERSION)
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);
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std::process::exit(0);
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return ControlFlow::Break(0);
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}
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'D' => {
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// TODO: Option is currently useless.
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@ -422,14 +421,14 @@ fn fish_parse_opt(args: &mut [WString], opts: &mut FishCmdOpts) -> usize {
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"{}",
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wgettext_fmt!(BUILTIN_ERR_UNKNOWN, "fish", args[w.woptind - 1])
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);
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std::process::exit(1)
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return ControlFlow::Break(1);
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}
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':' => {
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eprintln!(
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"{}",
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wgettext_fmt!(BUILTIN_ERR_MISSING, "fish", args[w.woptind - 1])
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);
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std::process::exit(1)
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return ControlFlow::Break(1);
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}
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_ => panic!("unexpected retval from wgetopter_t"),
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}
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@ -446,7 +445,7 @@ fn fish_parse_opt(args: &mut [WString], opts: &mut FishCmdOpts) -> usize {
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set_interactive_session(true);
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}
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optind
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ControlFlow::Continue(optind)
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}
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fn cstr_from_osstr(s: &OsStr) -> CString {
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@ -468,7 +467,7 @@ fn main() {
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panic_handler(throwing_main)
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}
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fn throwing_main() {
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fn throwing_main() -> i32 {
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let mut args: Vec<WString> = env::args_os()
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.map(|osstr| str2wcstring(osstr.as_bytes()))
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.collect();
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@ -478,7 +477,6 @@ fn throwing_main() {
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.expect("multiple entrypoints setting PROGRAM_NAME");
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let mut res = 1;
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let mut my_optind;
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signal_unblock_all();
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topic_monitor::topic_monitor_init();
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@ -503,7 +501,10 @@ fn throwing_main() {
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}
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let mut opts = FishCmdOpts::default();
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my_optind = fish_parse_opt(&mut args, &mut opts);
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let mut my_optind = match fish_parse_opt(&mut args, &mut opts) {
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ControlFlow::Continue(optind) => optind,
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ControlFlow::Break(status) => return status,
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};
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// Direct any debug output right away.
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// --debug-output takes precedence, otherwise $FISH_DEBUG_OUTPUT is used.
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@ -529,7 +530,7 @@ fn throwing_main() {
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// TODO: should not be debug-print
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eprintln!("Could not open file {:?}", debug_path);
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eprintln!("{}", e);
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std::process::exit(1);
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return 1;
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}
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};
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}
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@ -587,7 +588,9 @@ fn throwing_main() {
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features::set_from_string(opts.features.as_utfstr());
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proc_init();
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fish::env::misc_init();
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reader_init();
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let _restore_term_foreground_process_group =
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ScopeGuard::new((), |()| restore_term_foreground_process_group_for_exit());
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let _restore_term = reader_init();
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let parser = Parser::principal_parser();
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parser.set_syncs_uvars(!opts.no_config);
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@ -659,7 +662,7 @@ fn throwing_main() {
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"no-execute mode enabled and no script given. Exiting"
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);
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// above line should always exit
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std::process::exit(libc::EXIT_FAILURE);
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return libc::EXIT_FAILURE;
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}
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res = reader_read(parser, libc::STDIN_FILENO, &IoChain::new());
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} else {
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@ -718,10 +721,6 @@ fn throwing_main() {
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vec![exit_status.to_wstring()],
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);
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restore_term_mode();
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// this is ported, but not adopted
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restore_term_foreground_process_group_for_exit();
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if let Some(profile_output) = opts.profile_output {
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let s = cstr_from_osstr(&profile_output);
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parser.emit_profiling(s.as_bytes());
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@ -732,8 +731,7 @@ fn throwing_main() {
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print_rusage_self();
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}
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asan_maybe_exit(exit_status);
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exit_without_destructors(exit_status)
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exit_status
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}
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// https://github.com/fish-shell/fish-shell/issues/367
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@ -741,7 +741,7 @@ fn main() {
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panic_handler(throwing_main)
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}
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fn throwing_main() {
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fn throwing_main() -> i32 {
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PROGRAM_NAME.set(L!("fish_indent")).unwrap();
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topic_monitor_init();
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threads::init();
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@ -815,7 +815,7 @@ fn throwing_main() {
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'P' => DUMP_PARSE_TREE.store(true),
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'h' => {
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print_help("fish_indent");
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std::process::exit(STATUS_CMD_OK.unwrap());
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return STATUS_CMD_OK.unwrap();
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}
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'v' => {
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printf!(
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@ -826,7 +826,7 @@ fn throwing_main() {
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fish::BUILD_VERSION
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)
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);
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std::process::exit(STATUS_CMD_OK.unwrap());
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return STATUS_CMD_OK.unwrap();
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}
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'w' => output_type = OutputType::File,
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'i' => do_indent = false,
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@ -849,7 +849,7 @@ fn throwing_main() {
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'o' => {
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debug_output = Some(w.woptarg.unwrap());
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}
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_ => std::process::exit(STATUS_CMD_ERROR.unwrap()),
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_ => return STATUS_CMD_ERROR.unwrap(),
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}
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}
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@ -865,7 +865,7 @@ fn throwing_main() {
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if file.is_null() {
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eprintf!("Could not open file %s\n", debug_output);
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perror("fopen");
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std::process::exit(-1);
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return -1;
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}
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let fd = unsafe { libc::fileno(file) };
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set_cloexec(fd, true);
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@ -887,11 +887,11 @@ fn throwing_main() {
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PROGRAM_NAME.get().unwrap()
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)
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);
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std::process::exit(STATUS_CMD_ERROR.unwrap());
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return STATUS_CMD_ERROR.unwrap();
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}
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match read_file(stdin()) {
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Ok(s) => src = s,
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Err(()) => std::process::exit(STATUS_CMD_ERROR.unwrap()),
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Err(()) => return STATUS_CMD_ERROR.unwrap(),
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}
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} else {
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let arg = args[i];
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Ok(file) => {
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match read_file(file) {
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Ok(s) => src = s,
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Err(()) => std::process::exit(STATUS_CMD_ERROR.unwrap()),
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Err(()) => return STATUS_CMD_ERROR.unwrap(),
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}
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output_location = arg;
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}
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@ -908,7 +908,7 @@ fn throwing_main() {
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"%s",
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wgettext_fmt!("Opening \"%s\" failed: %s\n", arg, err.to_string())
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);
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std::process::exit(STATUS_CMD_ERROR.unwrap());
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return STATUS_CMD_ERROR.unwrap();
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}
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}
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}
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@ -953,7 +953,7 @@ fn throwing_main() {
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err.to_string()
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)
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);
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std::process::exit(STATUS_CMD_ERROR.unwrap());
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return STATUS_CMD_ERROR.unwrap();
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}
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}
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}
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@ -983,7 +983,7 @@ fn throwing_main() {
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let _ = write_to_fd(&colored_output, STDOUT_FILENO);
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i += 1;
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}
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std::process::exit(retval)
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retval
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}
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static DUMP_PARSE_TREE: RelaxedAtomicBool = RelaxedAtomicBool::new(false);
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@ -7,7 +7,9 @@
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//!
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//! Type "exit" or "quit" to terminate the program.
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use core::panic;
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use std::{
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ops::ControlFlow,
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os::unix::prelude::OsStrExt,
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time::{Duration, Instant},
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};
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@ -29,10 +31,7 @@ use fish::{
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print_help::print_help,
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printf,
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proc::set_interactive_session,
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reader::{
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check_exit_loop_maybe_warning, reader_init, reader_test_and_clear_interrupted,
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restore_term_mode,
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},
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reader::{check_exit_loop_maybe_warning, reader_init, reader_test_and_clear_interrupted},
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signal::signal_set_handlers,
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threads,
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topic_monitor::topic_monitor_init,
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@ -222,7 +221,7 @@ fn output_elapsed_time(prev_timestamp: Instant, first_char_seen: bool, verbose:
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}
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/// Process the characters we receive as the user presses keys.
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fn process_input(continuous_mode: bool, verbose: bool) {
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fn process_input(continuous_mode: bool, verbose: bool) -> i32 {
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let mut first_char_seen = false;
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let mut prev_timestamp = Instant::now()
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.checked_sub(Duration::from_millis(1000))
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@ -243,7 +242,7 @@ fn process_input(continuous_mode: bool, verbose: bool) {
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if evt.as_ref().is_none_or(|evt| !evt.is_char()) {
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output_bind_command(&mut bind_chars);
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if first_char_seen && !continuous_mode {
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return;
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return 0;
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}
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continue;
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}
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@ -271,15 +270,16 @@ fn process_input(continuous_mode: bool, verbose: bool) {
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first_char_seen = true;
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}
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0
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}
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/// Setup our environment (e.g., tty modes), process key strokes, then reset the environment.
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fn setup_and_process_keys(continuous_mode: bool, verbose: bool) -> ! {
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fn setup_and_process_keys(continuous_mode: bool, verbose: bool) -> i32 {
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set_interactive_session(true);
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topic_monitor_init();
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threads::init();
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env_init(None, true, false);
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reader_init();
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let _restore_term = reader_init();
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signal_set_handlers(true);
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// We need to set the shell-modes for ICRNL,
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@ -298,12 +298,10 @@ fn setup_and_process_keys(continuous_mode: bool, verbose: bool) -> ! {
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eprintf!("\n");
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}
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process_input(continuous_mode, verbose);
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restore_term_mode();
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std::process::exit(0);
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process_input(continuous_mode, verbose)
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}
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fn parse_flags(continuous_mode: &mut bool, verbose: &mut bool) -> bool {
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fn parse_flags(continuous_mode: &mut bool, verbose: &mut bool) -> ControlFlow<i32> {
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let short_opts: &wstr = L!("+chvV");
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let long_opts: &[woption] = &[
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wopt(L!("continuous"), woption_argument_t::no_argument, 'c'),
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|
@ -324,7 +322,7 @@ fn parse_flags(continuous_mode: &mut bool, verbose: &mut bool) -> bool {
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}
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'h' => {
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print_help("fish_key_reader");
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std::process::exit(0);
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return ControlFlow::Break(0);
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}
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'v' => {
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printf!(
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|
@ -335,7 +333,7 @@ fn parse_flags(continuous_mode: &mut bool, verbose: &mut bool) -> bool {
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fish::BUILD_VERSION
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)
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);
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std::process::exit(0);
|
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return ControlFlow::Break(0);
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}
|
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'V' => {
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*verbose = true;
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|
@ -349,7 +347,7 @@ fn parse_flags(continuous_mode: &mut bool, verbose: &mut bool) -> bool {
|
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w.argv[w.woptind - 1]
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)
|
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);
|
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return false;
|
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return ControlFlow::Break(1);
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}
|
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_ => panic!(),
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}
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|
@ -358,29 +356,29 @@ fn parse_flags(continuous_mode: &mut bool, verbose: &mut bool) -> bool {
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let argc = args.len() - w.woptind;
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if argc != 0 {
|
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eprintf!("Expected no arguments, got %d\n", argc);
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return false;
|
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return ControlFlow::Break(1);
|
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}
|
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|
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true
|
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ControlFlow::Continue(())
|
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}
|
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|
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fn main() {
|
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panic_handler(throwing_main)
|
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}
|
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|
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fn throwing_main() {
|
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fn throwing_main() -> i32 {
|
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PROGRAM_NAME.set(L!("fish_key_reader")).unwrap();
|
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let mut continuous_mode = false;
|
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let mut verbose = false;
|
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|
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if !parse_flags(&mut continuous_mode, &mut verbose) {
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std::process::exit(1);
|
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if let ControlFlow::Break(i) = parse_flags(&mut continuous_mode, &mut verbose) {
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return i;
|
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}
|
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|
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if unsafe { libc::isatty(STDIN_FILENO) } == 0 {
|
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eprintf!("Stdin must be attached to a tty.\n");
|
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std::process::exit(1);
|
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return 1;
|
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}
|
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|
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setup_and_process_keys(continuous_mode, verbose);
|
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setup_and_process_keys(continuous_mode, verbose)
|
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}
|
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|
|
21
src/panic.rs
21
src/panic.rs
|
@ -5,15 +5,21 @@ use libc::STDIN_FILENO;
|
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use crate::{
|
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common::{read_blocked, PROGRAM_NAME},
|
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nix::isatty,
|
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threads::asan_maybe_exit,
|
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};
|
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|
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pub fn panic_handler(main: impl FnOnce() + UnwindSafe) -> ! {
|
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pub fn panic_handler(main: impl FnOnce() -> i32 + UnwindSafe) -> ! {
|
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let exit_status = panic_handler_impl(main);
|
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asan_maybe_exit(exit_status);
|
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std::process::exit(exit_status)
|
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}
|
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|
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fn panic_handler_impl(main: impl FnOnce() -> i32 + UnwindSafe) -> i32 {
|
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if !isatty(STDIN_FILENO) {
|
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main();
|
||||
unreachable!();
|
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return main();
|
||||
}
|
||||
if catch_unwind(main).is_ok() {
|
||||
unreachable!();
|
||||
if let Ok(status) = catch_unwind(main) {
|
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return status;
|
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}
|
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printf!(
|
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"%s with PID %d crashed, please report a bug. Press Enter to exit",
|
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|
@ -23,11 +29,12 @@ pub fn panic_handler(main: impl FnOnce() + UnwindSafe) -> ! {
|
|||
let mut buf = [0_u8; 1];
|
||||
loop {
|
||||
let Ok(n) = read_blocked(STDIN_FILENO, &mut buf) else {
|
||||
std::process::exit(110);
|
||||
break;
|
||||
};
|
||||
if n == 0 || matches!(buf[0], b'q' | b'\n' | b'\r') {
|
||||
printf!("\n");
|
||||
std::process::exit(110);
|
||||
break;
|
||||
}
|
||||
}
|
||||
110
|
||||
}
|
||||
|
|
|
@ -41,8 +41,8 @@ use crate::color::RgbColor;
|
|||
use crate::common::{
|
||||
escape, escape_string, exit_without_destructors, get_ellipsis_char, get_obfuscation_read_char,
|
||||
redirect_tty_output, scoped_push_replacer, scoped_push_replacer_ctx, shell_modes, str2wcstring,
|
||||
wcs2string, write_loop, EscapeFlags, EscapeStringStyle, ScopeGuard, PROGRAM_NAME,
|
||||
UTF8_BOM_WCHAR,
|
||||
wcs2string, write_loop, EscapeFlags, EscapeStringStyle, ScopeGuard, ScopeGuarding,
|
||||
PROGRAM_NAME, UTF8_BOM_WCHAR,
|
||||
};
|
||||
use crate::complete::{
|
||||
complete, complete_load, sort_and_prioritize, CompleteFlags, Completion, CompletionList,
|
||||
|
@ -757,7 +757,7 @@ fn read_ni(parser: &Parser, fd: RawFd, io: &IoChain) -> i32 {
|
|||
}
|
||||
|
||||
/// Initialize the reader.
|
||||
pub fn reader_init() {
|
||||
pub fn reader_init() -> impl ScopeGuarding<Target = ()> {
|
||||
// Save the initial terminal mode.
|
||||
let mut terminal_mode_on_startup = TERMINAL_MODE_ON_STARTUP.lock().unwrap();
|
||||
unsafe { libc::tcgetattr(STDIN_FILENO, &mut *terminal_mode_on_startup) };
|
||||
|
@ -784,6 +784,9 @@ pub fn reader_init() {
|
|||
if is_interactive_session() && unsafe { libc::getpgrp() == libc::tcgetpgrp(STDIN_FILENO) } {
|
||||
term_donate(/*quiet=*/ true);
|
||||
}
|
||||
ScopeGuard::new((), |()| {
|
||||
restore_term_mode();
|
||||
})
|
||||
}
|
||||
|
||||
/// Restore the term mode if we own the terminal and are interactive (#8705).
|
||||
|
|
|
@ -27,6 +27,7 @@ mod topic_monitor;
|
|||
mod wgetopt;
|
||||
|
||||
pub mod prelude {
|
||||
use crate::common::ScopeGuarding;
|
||||
use crate::env::{env_init, misc_init};
|
||||
use crate::reader::reader_init;
|
||||
use crate::signal::signal_reset_handlers;
|
||||
|
@ -60,7 +61,7 @@ pub mod prelude {
|
|||
EnvStack::principal().set_pwd_from_getcwd();
|
||||
}
|
||||
|
||||
pub fn test_init() {
|
||||
pub fn test_init() -> impl ScopeGuarding<Target = ()> {
|
||||
static DONE: OnceCell<()> = OnceCell::new();
|
||||
DONE.get_or_init(|| {
|
||||
set_current_dir(env!("FISH_BUILD_DIR")).unwrap();
|
||||
|
@ -75,7 +76,6 @@ pub mod prelude {
|
|||
proc_init();
|
||||
env_init(None, true, false);
|
||||
misc_init();
|
||||
reader_init();
|
||||
|
||||
// Set default signal handlers, so we can ctrl-C out of this.
|
||||
signal_reset_handlers();
|
||||
|
@ -83,6 +83,7 @@ pub mod prelude {
|
|||
// Set PWD from getcwd - fixes #5599
|
||||
EnvStack::principal().set_pwd_from_getcwd();
|
||||
});
|
||||
reader_init()
|
||||
}
|
||||
|
||||
pub use serial_test::serial;
|
||||
|
|
Loading…
Reference in New Issue
Block a user