From 36d6eb95c1de72b1c5703c5204124abe589d34b1 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Thu, 24 Jul 2014 15:51:21 +0100 Subject: [PATCH] Fix pagination crash when the TUI is active The TUI currently crashes when the user types in response to a pagination prompt: $ gdb --tui ... *the TUI is now active* (gdb) set height 2 (gdb) help List of classes of commands: Program received signal SIGSEGV, Segmentation fault. strlen () at ../sysdeps/x86_64/strlen.S:106 106 movdqu (%rax), %xmm12 (top-gdb) bt #0 strlen () at ../sysdeps/x86_64/strlen.S:106 #1 0x000000000086be5f in xstrdup (s=0x0) at ../src/libiberty/xstrdup.c:33 #2 0x00000000005163f9 in tui_prep_terminal (notused1=1) at ../src/gdb/tui/tui-io.c:296 #3 0x000000000077a7ee in _rl_callback_newline () at ../src/readline/callback.c:82 #4 0x000000000077a853 in rl_callback_handler_install (prompt=0x0, linefunc=0x618b60 ) at ../src/readline/callback.c:102 #5 0x0000000000718a5c in gdb_readline_wrapper_cleanup (arg=0xfd14d0) at ../src/gdb/top.c:788 #6 0x0000000000596d08 in do_my_cleanups (pmy_chain=0xcf0b38 , old_chain=0x1043d10) at ../src/gdb/cleanups.c:155 #7 0x0000000000596d75 in do_cleanups (old_chain=0x1043d10) at ../src/gdb/cleanups.c:177 #8 0x0000000000718bd9 in gdb_readline_wrapper (prompt=0x7fffffffcfa0 "---Type to continue, or q to quit---") at ../src/gdb/top.c:835 #9 0x000000000071cf74 in prompt_for_continue () at ../src/gdb/utils.c:1894 #10 0x000000000071d434 in fputs_maybe_filtered (linebuffer=0x1043db0 "List of classes of commands:\n\n", stream=0xf72e20, filter=1) at ../src/gdb/utils.c:2111 #11 0x000000000071da0f in vfprintf_maybe_filtered (stream=0xf72e20, format=0x89aef8 "List of classes of %scommands:\n\n", args=0x7fffffffd118, filter=1) at ../src/gdb/utils.c:2339 #12 0x000000000071da4a in vfprintf_filtered (stream=0xf72e20, format=0x89aef8 "List of classes of %scommands:\n\n", args=0x7fffffffd118) at ../src/gdb/utils.c:2347 #13 0x000000000071dc72 in fprintf_filtered (stream=0xf72e20, format=0x89aef8 "List of classes of %scommands:\n\n") at ../src/gdb/utils.c:2399 #14 0x00000000004f90ab in help_list (list=0xe6d100, cmdtype=0x89ad8c "", class=all_classes, stream=0xf72e20) at ../src/gdb/cli/cli-decode.c:1038 #15 0x00000000004f8dba in help_cmd (arg=0x0, stream=0xf72e20) at ../src/gdb/cli/cli-decode.c:946 Git 0017922 added: @@ -776,6 +777,12 @@ gdb_readline_wrapper_cleanup (void *arg) gdb_assert (input_handler == gdb_readline_wrapper_line); input_handler = cleanup->handler_orig; + + /* Reinstall INPUT_HANDLER in readline, without displaying a + prompt. */ + if (async_command_editing_p) + rl_callback_handler_install (NULL, input_handler); and tui_prep_terminal simply misses handling the case of a NULL rl_prompt. I also checked that readline's sources do similar checks. gdb/ 2014-07-24 Pedro Alves * tui/tui-io.c (tui_prep_terminal): Handle NULL rl_prompt. --- gdb/ChangeLog | 4 ++++ gdb/tui/tui-io.c | 2 +- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index e239221..1c4ccaf 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,7 @@ +2014-07-24 Pedro Alves + + * tui/tui-io.c (tui_prep_terminal): Handle NULL rl_prompt. + 2014-07-24 Tom Tromey Gary Benson diff --git a/gdb/tui/tui-io.c b/gdb/tui/tui-io.c index dcccb08..75eb4b8 100644 --- a/gdb/tui/tui-io.c +++ b/gdb/tui/tui-io.c @@ -293,7 +293,7 @@ tui_prep_terminal (int notused1) (we can't use gdb_prompt() due to secondary prompts and can't use rl_prompt because it points to an alloca buffer). */ xfree (tui_rl_saved_prompt); - tui_rl_saved_prompt = xstrdup (rl_prompt); + tui_rl_saved_prompt = rl_prompt != NULL ? xstrdup (rl_prompt) : NULL; } /* Readline callback to restore the terminal. It is called once each -- 2.7.4