33876: etc.: Separate errors and keyboards interrupts

Combination of 12 commits from interrupt_abort branch.

Basic strategy is to introduce bits to errflag and to set and
reset them separately.

Remove interrupt status on return to main keymap.

Turn off ERRFLAG_INT for always block.

Restore bit thereafter: we probably need a new variable in order
to allow user interrupts to be reset in the always block.

Add TRY_BLOCK_INTERRUPT

This works the same as TRY_BLOCK_ERROR, but for a SIGINT, too.

Ensure propagation of SIGINT from exited job.

If received by foreground job, shell uses ERRFLAG_INT, not
ERRFLAG_ERROR, to set the new state.

Reset errflag before precmd()

Add always block in _main_completion to fix ZLS_COLORS

Ensures we get the right state of $ZLS_COLORS at the end of _main_complete
even if there's an interrupt.  However, the "right state" is a bit messy
as it depends on styles.

1 files changed, 25 insertions, 4 deletions

diff --git a/Src/init.c b/Src/init.c
index 655166135..305908724 100644
--- a/Src/init.c
+++ b/Src/init.c
@@ -118,11 +118,24 @@ loop(int toplevel, int justonce)
 	    if (interact && toplevel) {
 	        int hstop = stophist;
 		stophist = 3;
+		/*
+		 * Reset all errors including the interrupt error status
+		 * immediately, so preprompt runs regardless of what
+		 * just happened.  We'll reset again below as a
+		 * precaution to ensure we get back to the command line
+		 * no matter what.
+		 */
+		errflag = 0;
 		preprompt();
 		if (stophist != 3)
 		    hbegin(1);
 		else
 		    stophist = hstop;
+		/*
+		 * Reset all errors, including user interupts.
+		 * This is what allows ^C in an interactive shell
+		 * to return us to the command line.
+		 */
 		errflag = 0;
 	    }
 	}
@@ -178,7 +191,15 @@ loop(int toplevel, int justonce)
 
 		/* The only permanent storage is from getpermtext() */
 		zsfree(cmdstr);
-		errflag = 0;
+		/*
+		 * Note this does *not* remove a user interrupt error
+		 * condition, even though we're at the top level loop:
+		 * that would be inconsistent with the case where
+		 * we didn't execute a preexec function.  This is
+		 * an implementation detail that an interrupting user
+		 * does't care about.
+		 */
+		errflag &= ~ERRFLAG_ERROR;
 	    }
 	    if (stopmsg)	/* unset 'you have stopped jobs' flag */
 		stopmsg--;
@@ -689,7 +710,7 @@ init_term(void)
     {
 	if (isset(INTERACTIVE))
 	    zerr("can't find terminal definition for %s", term);
-	errflag = 0;
+	errflag &= ~ERRFLAG_ERROR;
 	termflags |= TERM_BAD;
 	return 0;
     } else {
@@ -1336,7 +1357,7 @@ source(char *s)
 
     if (prog) {
 	pushheap();
-	errflag = 0;
+	errflag &= ~ERRFLAG_ERROR;
 	execode(prog, 1, 0, "filecode");
 	popheap();
 	if (errflag)
@@ -1379,7 +1400,7 @@ source(char *s)
     lineno = oldlineno;              /* our current lineno                   */
     loops = oloops;                  /* the # of nested loops we are in      */
     dosetopt(SHINSTDIN, oldshst, 1, opts); /* SHINSTDIN option               */
-    errflag = 0;
+    errflag &= ~ERRFLAG_ERROR;
     if (!exit_pending)
 	retflag = 0;
     scriptname = old_scriptname;