From 6aa899ce25d73c397748e4df926da3fd7e5870e5 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Mon, 6 Nov 2017 15:36:47 +0000 Subject: [PATCH] Eliminate STOP_SIGNAL, use SIGTSTP directly The STOP_SIGNAL macro was originally added for Convex Unix (https://en.wikipedia.org/wiki/Convex_Computer). In: git show 7a67dd45ca1c:gdb/m-convex.h we see: ~~~ /* Use SIGCONT rather than SIGTSTP because convex Unix occasionally turkeys SIGTSTP. I think. */ #define STOP_SIGNAL SIGCONT ~~~ That's gdb-3.5, 1990... In gdb/ChangeLog-3.x we see: ~~~ Tue Apr 18 13:43:37 1989 Randall Smith (randy at apple-gunkies.ai.mit.edu) Various changes involved in 1) getting gdb to work on the convex, [...] Made whatever signal indicates a stop configurable (via macro STOP_SIGNAL). (main): Setup use of above as a signal handler. Added check for "-nw" in args already processed. (command_line_input): SIGTSTP ==>STOP_SIGNAL. ~~~ Support for Convex Unix is long gone, and nothing else overrides STOP_SIGNAL. So just use SIGTSTP directly, removing a little obfuscation. (I don't really understand why we override [1] readline's SIGTSTP handler (only) when reading scripts (and then fail to restore it properly, assuming SIG_DFL...), but I'll leave that for another pass. [1] - Actually, starting with readline 6.3, readline is no longer installing its handlers while GDB is in control...) gdb/ChangeLog: 2017-11-06 Pedro Alves * event-top.c: Check SIGTSTP instead of STOP_SIGNAL thoughout. (async_init_signals): Adjust. (handle_stop_sig): Rename to ... (handle_sigtstp): ... this. (async_stop_sig): Rename to ... (async_sigtstp_handler): ... this, and delete STOP_SIGNAL != SIGTSTP path. * event-top.h: Move signal.h include to the top. Check SIGTSTP instead of STOP_SIGNAL thoughout. (handle_stop_sig): Rename to ... (handle_sigtstp): ... this. * top.c (command_line_input): Replace STOP_SIGNAL -> SIGTSTP. --- gdb/ChangeLog | 15 +++++++++++++++ gdb/event-top.c | 26 +++++++++++--------------- gdb/event-top.h | 10 ++++------ gdb/top.c | 8 ++++---- 4 files changed, 34 insertions(+), 25 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index c569d568ff..80caa43f47 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,18 @@ +2017-11-06 Pedro Alves + + * event-top.c: Check SIGTSTP instead of STOP_SIGNAL thoughout. + (async_init_signals): Adjust. + (handle_stop_sig): Rename to ... + (handle_sigtstp): ... this. + (async_stop_sig): Rename to ... + (async_sigtstp_handler): ... this, and delete STOP_SIGNAL != + SIGTSTP path. + * event-top.h: Move signal.h include to the top. Check SIGTSTP + instead of STOP_SIGNAL thoughout. + (handle_stop_sig): Rename to ... + (handle_sigtstp): ... this. + * top.c (command_line_input): Replace STOP_SIGNAL -> SIGTSTP. + 2017-11-06 Pedro Alves * inflow.c (child_terminal_inferior, child_terminal_ours_1): No diff --git a/gdb/event-top.c b/gdb/event-top.c index 43e2a27163..73771894c9 100644 --- a/gdb/event-top.c +++ b/gdb/event-top.c @@ -68,8 +68,8 @@ static void async_do_nothing (gdb_client_data); static void async_disconnect (gdb_client_data); #endif static void async_float_handler (gdb_client_data); -#ifdef STOP_SIGNAL -static void async_stop_sig (gdb_client_data); +#ifdef SIGTSTP +static void async_sigtstp_handler (gdb_client_data); #endif static void async_sigterm_handler (gdb_client_data arg); @@ -111,7 +111,7 @@ static struct async_signal_handler *sighup_token; static struct async_signal_handler *sigquit_token; #endif static struct async_signal_handler *sigfpe_token; -#ifdef STOP_SIGNAL +#ifdef SIGTSTP static struct async_signal_handler *sigtstp_token; #endif static struct async_signal_handler *async_sigterm_token; @@ -912,9 +912,9 @@ async_init_signals (void) sigfpe_token = create_async_signal_handler (async_float_handler, NULL); -#ifdef STOP_SIGNAL +#ifdef SIGTSTP sigtstp_token = - create_async_signal_handler (async_stop_sig, NULL); + create_async_signal_handler (async_sigtstp_handler, NULL); #endif } @@ -1112,20 +1112,19 @@ async_disconnect (gdb_client_data arg) } #endif -#ifdef STOP_SIGNAL +#ifdef SIGTSTP void -handle_stop_sig (int sig) +handle_sigtstp (int sig) { mark_async_signal_handler (sigtstp_token); - signal (sig, handle_stop_sig); + signal (sig, handle_sigtstp); } static void -async_stop_sig (gdb_client_data arg) +async_sigtstp_handler (gdb_client_data arg) { char *prompt = get_prompt (); -#if STOP_SIGNAL == SIGTSTP signal (SIGTSTP, SIG_DFL); #if HAVE_SIGPROCMASK { @@ -1138,10 +1137,7 @@ async_stop_sig (gdb_client_data arg) sigsetmask (0); #endif raise (SIGTSTP); - signal (SIGTSTP, handle_stop_sig); -#else - signal (STOP_SIGNAL, handle_stop_sig); -#endif + signal (SIGTSTP, handle_sigtstp); printf_unfiltered ("%s", prompt); gdb_flush (gdb_stdout); @@ -1149,7 +1145,7 @@ async_stop_sig (gdb_client_data arg) nothing. */ dont_repeat (); } -#endif /* STOP_SIGNAL */ +#endif /* SIGTSTP */ /* Tell the event loop what to do if SIGFPE is received. See event-signal.c. */ diff --git a/gdb/event-top.h b/gdb/event-top.h index 05241ad0a6..d069c568f9 100644 --- a/gdb/event-top.h +++ b/gdb/event-top.h @@ -22,6 +22,8 @@ #ifndef EVENT_TOP_H #define EVENT_TOP_H +#include + struct cmd_list_element; /* Exported functions from event-top.c. @@ -36,14 +38,10 @@ extern void change_line_handler (int); extern void command_line_handler (char *rl); extern void command_handler (char *command); -/* Signal to catch ^Z typed while reading a command: SIGTSTP or SIGCONT. */ -#ifndef STOP_SIGNAL -#include #ifdef SIGTSTP -#define STOP_SIGNAL SIGTSTP -extern void handle_stop_sig (int sig); -#endif +extern void handle_sigtstp (int sig); #endif + extern void handle_sigint (int sig); extern void handle_sigterm (int sig); extern void async_request_quit (void *arg); diff --git a/gdb/top.c b/gdb/top.c index 9f5dd58d21..f006c669a1 100644 --- a/gdb/top.c +++ b/gdb/top.c @@ -1184,9 +1184,9 @@ command_line_input (const char *prompt_arg, int repeat, /* Starting a new command line. */ cmd_line_buffer.used_size = 0; -#ifdef STOP_SIGNAL +#ifdef SIGTSTP if (job_control) - signal (STOP_SIGNAL, handle_stop_sig); + signal (SIGTSTP, handle_sigtstp); #endif while (1) @@ -1244,9 +1244,9 @@ command_line_input (const char *prompt_arg, int repeat, prompt = NULL; } -#ifdef STOP_SIGNAL +#ifdef SIGTSTP if (job_control) - signal (STOP_SIGNAL, SIG_DFL); + signal (SIGTSTP, SIG_DFL); #endif return cmd; -- 2.34.1