21296: Add ERR alias for ZERR where possible.

"trap" reports alias names.

3 files changed, 48 insertions, 27 deletions

diff --git a/Src/builtin.c b/Src/builtin.c
index 09034c514..69d78c926 100644
--- a/Src/builtin.c
+++ b/Src/builtin.c
@@ -4978,13 +4978,14 @@ bin_trap(char *name, char **argv, UNUSED(Options ops), UNUSED(int func))
 		    shfunctab->printnode(hn, 0);
 		DPUTS(!hn, "BUG: I did not find any trap functions!");
 	    } else if (sigtrapped[sig]) {
+		char *name = getsigname(sig);
 		if (!siglists[sig])
-		    printf("trap -- '' %s\n", sigs[sig]);
+		    printf("trap -- '' %s\n", name);
 		else {
 		    s = getpermtext(siglists[sig], NULL);
 		    printf("trap -- ");
 		    quotedzputs(s, stdout);
-		    printf(" %s\n", sigs[sig]);
+		    printf(" %s\n", name);
 		    zsfree(s);
 		}
 	    }
@@ -5017,14 +5018,25 @@ bin_trap(char *name, char **argv, UNUSED(Options ops), UNUSED(int func))
     /* set traps */
     for (; *argv; argv++) {
 	Eprog t;
+	int flags;
 
 	sig = getsignum(*argv);
 	if (sig == -1) {
 	    zwarnnam(name, "undefined signal: %s", *argv, 0);
 	    break;
 	}
+	if (!strcmp(sigs[sig], *argv))
+	    flags = 0;
+	else {
+	    /*
+	     * Record that the signal is used under an assumed name.
+	     * If we ever have more than one alias per signal this
+	     * will need improving.
+	     */
+	    flags = ZSIG_ALIAS;
+	}
 	t = dupeprog(prog, 0);
-	if (settrap(sig, t, 0))
+	if (settrap(sig, t, flags))
 	    freeeprog(t);
     }
     return *argv != NULL;
diff --git a/Src/jobs.c b/Src/jobs.c
index 5c1574acf..f5ade7c2b 100644
--- a/Src/jobs.c
+++ b/Src/jobs.c
@@ -1819,18 +1819,6 @@ bin_fg(char *name, char **argv, Options ops, int func)
     return retval;
 }
 
-#if defined(SIGCHLD) && defined(SIGCLD)
-#if SIGCHLD == SIGCLD
-#define ALT_SIGS 1
-#endif
-#endif
-#if defined(SIGPOLL) && defined(SIGIO)
-#if SIGPOLL == SIGIO
-#define ALT_SIGS 1
-#endif
-#endif
-
-#ifdef ALT_SIGS
 const struct {
     const char *name;
     int num;
@@ -1845,9 +1833,15 @@ const struct {
     { "IO", SIGIO },
 #endif
 #endif
+#if !defined(SIGERR)
+    /*
+     * If SIGERR is not defined by the operating system, use it
+     * as an alias for SIGZERR.
+     */
+    { "ERR", SIGZERR },
+#endif
     { NULL, 0 }
 };
-#endif
 
 /* kill: send a signal to a process.  The process(es) may be specified *
  * by job specifier (see above) or pid.  A signal, defaulting to       *
@@ -1879,7 +1873,6 @@ bin_kill(char *nam, char **argv, UNUSED(Options ops), UNUSED(int func))
 			    for (sig = 1; sig <= SIGCOUNT; sig++)
 				if (!cstrpcmp(sigs + sig, &signame))
 				    break;
-#ifdef ALT_SIGS
 			    if (sig > SIGCOUNT) {
 				int i;
 
@@ -1890,7 +1883,6 @@ bin_kill(char *nam, char **argv, UNUSED(Options ops), UNUSED(int func))
 					break;
 				    }
 			    }
-#endif
 			    if (sig > SIGCOUNT) {
 				zwarnnam(nam, "unknown signal: SIG%s",
 					 signame, 0);
@@ -1953,7 +1945,6 @@ bin_kill(char *nam, char **argv, UNUSED(Options ops), UNUSED(int func))
 			break;
 		if (*signame == '0' && !signame[1])
 		    sig = 0;
-#ifdef ALT_SIGS
 		if (sig > SIGCOUNT) {
 		    int i;
 
@@ -1964,7 +1955,6 @@ bin_kill(char *nam, char **argv, UNUSED(Options ops), UNUSED(int func))
 			    break;
 			}
 		}
-#endif
 		if (sig > SIGCOUNT) {
 		    zwarnnam(nam, "unknown signal: SIG%s", signame, 0);
 		    zwarnnam(nam, "type kill -l for a List of signals", NULL, 0);
@@ -2042,18 +2032,40 @@ getsignum(char *s)
 	if (!strcmp(s, sigs[i]))
 	    return i;
 
-#ifdef ALT_SIGS
     for (i = 0; alt_sigs[i].name; i++)
     {
 	if (!strcmp(s, alt_sigs[i].name))
 	    return alt_sigs[i].num;
     }
-#endif
 
     /* no matching signal */
     return -1;
 }
 
+/* Get the name for a signal. */
+
+/**/
+mod_export const char *
+getsigname(int sig)
+{
+    if (sigtrapped[sig] & ZSIG_ALIAS)
+    {
+	int i;
+	for (i = 0; alt_sigs[i].name; i++)
+	    if (sig == alt_sigs[i].num)
+		return alt_sigs[i].name;
+    }
+    else
+	return sigs[sig];
+
+    /* shouldn't reach here */
+#ifdef DEBUG
+    dputs("Bad alias flag for signal");
+#endif
+    return "";
+}
+
+
 /* Get the function node for a trap, taking care about alternative names */
 /**/
 HashNode
@@ -2062,9 +2074,7 @@ gettrapnode(int sig, int ignoredisable)
     char fname[20];
     HashNode hn;
     HashNode (*getptr)(HashTable ht, char *name);
-#ifdef ALT_SIGS
     int i;
-#endif
     if (ignoredisable)
 	getptr = shfunctab->getnode2;
     else
@@ -2074,7 +2084,6 @@ gettrapnode(int sig, int ignoredisable)
     if ((hn = getptr(shfunctab, fname)))
 	return hn;
 
-#ifdef ALT_SIGS
     for (i = 0; alt_sigs[i].name; i++) {
 	if (alt_sigs[i].num == sig) {
 	    sprintf(fname, "TRAP%s", alt_sigs[i].name);
@@ -2082,7 +2091,6 @@ gettrapnode(int sig, int ignoredisable)
 		return hn;
 	}
     }
-#endif
 
     return NULL;
 }
diff --git a/Src/zsh.h b/Src/zsh.h
index 6e1916690..3dacf637f 100644
--- a/Src/zsh.h
+++ b/Src/zsh.h
@@ -1852,7 +1852,8 @@ struct heap {
 /* Mask to get the above flags */
 #define ZSIG_MASK	(ZSIG_TRAPPED|ZSIG_IGNORED|ZSIG_FUNC)
 /* No. of bits to shift local level when storing in sigtrapped */
-#define ZSIG_SHIFT	3
+#define ZSIG_ALIAS	(1<<3)  /* Trap is stored under an alias */
+#define ZSIG_SHIFT	4
 
 /**********************************/
 /* Flags to third argument of zle */