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commit a5faae14cd81c019b8757c2f263799d19a2218e0
parent c95bdf7ce9be6c6ed8ca4b0a474fc4947836eba9
Author: Bert Münnich <ber.t@posteo.de>
Date:   Sat, 28 Nov 2015 15:48:46 +0100

Restore signal handlers when catching signals in edit_alloc()

edit_catcher() performs a longjmp via rc_raise() to the matching setjmp in
doit(). The latter does the same as before, so that edit_alloc() gets called
again, but this time the installation of the signal handlers trashes the old
handlers saved in the last call. Once readline() returns normally to
edit_alloc() the wrong signal handlers get restored.

The simplified call hierarchy looks like this:

doit();
  sigsetjmp();
    edit_alloc();
      oldint = sys_signal(SIGINT, edit_catcher);
      readline();
        SIGINT -> edit_catcher();
          siglongjmp();
      sys_signal(SIGINT, oldint);

Restoring the old signal handlers in edit_catcher() solves this.

Diffstat:
Medit-edit.c | 5++++-
Medit-editline.c | 5++++-
Medit-readline.c | 5++++-
Medit-vrl.c | 5++++-
4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/edit-edit.c b/edit-edit.c @@ -37,7 +37,11 @@ void *edit_begin(int fd) { } +static void (*oldint)(int), (*oldquit)(int); + static void edit_catcher(int sig) { + sys_signal(SIGINT, oldint); + sys_signal(SIGQUIT, oldquit); write(2, "\n", 1); rc_raise(eError); } @@ -46,7 +50,6 @@ char *edit_alloc(void *cookie, size_t *count) { const char *r; HistEvent he; struct cookie *c = cookie; - void (*oldint)(int), (*oldquit)(int); oldint = sys_signal(SIGINT, edit_catcher); oldquit = sys_signal(SIGQUIT, edit_catcher); diff --git a/edit-editline.c b/edit-editline.c @@ -29,7 +29,11 @@ void *edit_begin(int fd) { } /* +static void (*oldint)(int), (*oldquit)(int); + static void edit_catcher(int sig) { + sys_signal(SIGINT, oldint); + sys_signal(SIGQUIT, oldquit); write(2, "\n", 1); rc_raise(eError); } @@ -42,7 +46,6 @@ char *edit_alloc(void *cookie, size_t *count) { const char *r; HistEvent he; struct cookie *c = cookie; - void (*oldint)(int), (*oldquit)(int); oldint = sys_signal(SIGINT, edit_catcher); oldquit = sys_signal(SIGQUIT, edit_catcher); diff --git a/edit-readline.c b/edit-readline.c @@ -32,7 +32,11 @@ void *edit_begin(int fd) { return c; } +static void (*oldint)(int), (*oldquit)(int); + static void edit_catcher(int sig) { + sys_signal(SIGINT, oldint); + sys_signal(SIGQUIT, oldquit); write(2, "\n", 1); rc_raise(eError); } @@ -41,7 +45,6 @@ static char *prompt; char *edit_alloc(void *cookie, size_t *count) { struct cookie *c = cookie; - void (*oldint)(int), (*oldquit)(int); oldint = sys_signal(SIGINT, edit_catcher); oldquit = sys_signal(SIGQUIT, edit_catcher); diff --git a/edit-vrl.c b/edit-vrl.c @@ -32,7 +32,11 @@ void *edit_begin(int fd) { } /* +static void (*oldint)(int), (*oldquit)(int); + static void edit_catcher(int sig) { + sys_signal(SIGINT, oldint); + sys_signal(SIGQUIT, oldquit); write(2, "\n", 1); rc_raise(eError); } @@ -45,7 +49,6 @@ char *edit_alloc(void *cookie, size_t *count) { const char *r; HistEvent he; struct cookie *c = cookie; - void (*oldint)(int), (*oldquit)(int); oldint = sys_signal(SIGINT, edit_catcher); oldquit = sys_signal(SIGQUIT, edit_catcher);