From e22b245ea576bf1787284971b467f45f45045f97 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Carlo=20Marcelo=20Arenas=20Bel=C3=B3n?= Date: Tue, 5 Oct 2021 00:46:47 -0700 Subject: [PATCH 1/2] terminal: teach git how to save/restore its terminal settings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, git will share its console with all its children (unless they create their own), and is therefore possible that any of them that might change the settings for it could affect its operations once completed. Refactor the platform specific functionality to save the terminal settings and expand it to also do so for the output handler. This will allow for the state of the terminal to be saved and restored around a child that might misbehave (ex vi) which will be implemented next. Signed-off-by: Carlo Marcelo Arenas Belón Signed-off-by: Junio C Hamano --- compat/terminal.c | 75 +++++++++++++++++++++++++++++++++++++---------- compat/terminal.h | 3 ++ 2 files changed, 63 insertions(+), 15 deletions(-) diff --git a/compat/terminal.c b/compat/terminal.c index 43b73ddc75..5b903e7c7e 100644 --- a/compat/terminal.c +++ b/compat/terminal.c @@ -8,8 +8,6 @@ #if defined(HAVE_DEV_TTY) || defined(GIT_WINDOWS_NATIVE) -static void restore_term(void); - static void restore_term_on_signal(int sig) { restore_term(); @@ -25,7 +23,7 @@ static void restore_term_on_signal(int sig) static int term_fd = -1; static struct termios old_term; -static void restore_term(void) +void restore_term(void) { if (term_fd < 0) return; @@ -35,15 +33,22 @@ static void restore_term(void) term_fd = -1; } +int save_term(int full_duplex) +{ + if (term_fd < 0) + term_fd = open("/dev/tty", O_RDWR); + + return (term_fd < 0) ? -1 : tcgetattr(term_fd, &old_term); +} + static int disable_bits(tcflag_t bits) { struct termios t; - term_fd = open("/dev/tty", O_RDWR); - if (tcgetattr(term_fd, &t) < 0) + if (save_term(0) < 0) goto error; - old_term = t; + t = old_term; sigchain_push_common(restore_term_on_signal); t.c_lflag &= ~bits; @@ -75,9 +80,10 @@ static int enable_non_canonical(void) static int use_stty = 1; static struct string_list stty_restore = STRING_LIST_INIT_DUP; static HANDLE hconin = INVALID_HANDLE_VALUE; -static DWORD cmode; +static HANDLE hconout = INVALID_HANDLE_VALUE; +static DWORD cmode_in, cmode_out; -static void restore_term(void) +void restore_term(void) { if (use_stty) { int i; @@ -97,9 +103,42 @@ static void restore_term(void) if (hconin == INVALID_HANDLE_VALUE) return; - SetConsoleMode(hconin, cmode); + SetConsoleMode(hconin, cmode_in); + CloseHandle(hconin); + if (cmode_out) { + assert(hconout != INVALID_HANDLE_VALUE); + SetConsoleMode(hconout, cmode_out); + CloseHandle(hconout); + } + + hconin = hconout = INVALID_HANDLE_VALUE; +} + +int save_term(int full_duplex) +{ + hconin = CreateFileA("CONIN$", GENERIC_READ | GENERIC_WRITE, + FILE_SHARE_READ, NULL, OPEN_EXISTING, + FILE_ATTRIBUTE_NORMAL, NULL); + if (hconin == INVALID_HANDLE_VALUE) + return -1; + + if (full_duplex) { + hconout = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, + FILE_SHARE_WRITE, NULL, OPEN_EXISTING, + FILE_ATTRIBUTE_NORMAL, NULL); + if (hconout == INVALID_HANDLE_VALUE) + goto error; + + GetConsoleMode(hconout, &cmode_out); + } + + GetConsoleMode(hconin, &cmode_in); + use_stty = 0; + return 0; +error: CloseHandle(hconin); hconin = INVALID_HANDLE_VALUE; + return -1; } static int disable_bits(DWORD bits) @@ -135,15 +174,11 @@ static int disable_bits(DWORD bits) use_stty = 0; } - hconin = CreateFile("CONIN$", GENERIC_READ | GENERIC_WRITE, - FILE_SHARE_READ, NULL, OPEN_EXISTING, - FILE_ATTRIBUTE_NORMAL, NULL); - if (hconin == INVALID_HANDLE_VALUE) + if (save_term(0) < 0) return -1; - GetConsoleMode(hconin, &cmode); sigchain_push_common(restore_term_on_signal); - if (!SetConsoleMode(hconin, cmode & ~bits)) { + if (!SetConsoleMode(hconin, cmode_in & ~bits)) { CloseHandle(hconin); hconin = INVALID_HANDLE_VALUE; return -1; @@ -361,6 +396,16 @@ int read_key_without_echo(struct strbuf *buf) #else +int save_term(int full_duplex) +{ + /* full_duplex == 1, but no support available */ + return -full_duplex; +} + +void restore_term(void) +{ +} + char *git_terminal_prompt(const char *prompt, int echo) { return getpass(prompt); diff --git a/compat/terminal.h b/compat/terminal.h index a9d52b8464..e1770c575b 100644 --- a/compat/terminal.h +++ b/compat/terminal.h @@ -1,6 +1,9 @@ #ifndef COMPAT_TERMINAL_H #define COMPAT_TERMINAL_H +int save_term(int full_duplex); +void restore_term(void); + char *git_terminal_prompt(const char *prompt, int echo); /* Read a single keystroke, without echoing it to the terminal */ From 3d411afabc9a96f41d47c07d6af6edda3d29ec92 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Carlo=20Marcelo=20Arenas=20Bel=C3=B3n?= Date: Tue, 5 Oct 2021 00:46:48 -0700 Subject: [PATCH 2/2] editor: save and reset terminal after calling EDITOR MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When EDITOR is invoked to modify a commit message, it will likely change the terminal settings, and if it misbehaves will leave the terminal output damaged as shown in a recent report from Windows Terminal[1] Instead use the functions provided by compat/terminal to save the settings and recover safely. [1] https://github.com/microsoft/terminal/issues/9359 Signed-off-by: Carlo Marcelo Arenas Belón Signed-off-by: Junio C Hamano --- editor.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/editor.c b/editor.c index 6303ae0ab0..be7441e7e0 100644 --- a/editor.c +++ b/editor.c @@ -3,6 +3,7 @@ #include "strbuf.h" #include "run-command.h" #include "sigchain.h" +#include "compat/terminal.h" #ifndef DEFAULT_EDITOR #define DEFAULT_EDITOR "vi" @@ -50,6 +51,8 @@ const char *git_sequence_editor(void) static int launch_specified_editor(const char *editor, const char *path, struct strbuf *buffer, const char *const *env) { + int term_fail; + if (!editor) return error("Terminal is dumb, but EDITOR unset"); @@ -83,7 +86,10 @@ static int launch_specified_editor(const char *editor, const char *path, p.env = env; p.use_shell = 1; p.trace2_child_class = "editor"; + term_fail = save_term(1); if (start_command(&p) < 0) { + if (!term_fail) + restore_term(); strbuf_release(&realpath); return error("unable to start editor '%s'", editor); } @@ -91,6 +97,8 @@ static int launch_specified_editor(const char *editor, const char *path, sigchain_push(SIGINT, SIG_IGN); sigchain_push(SIGQUIT, SIG_IGN); ret = finish_command(&p); + if (!term_fail) + restore_term(); strbuf_release(&realpath); sig = ret - 128; sigchain_pop(SIGINT);