X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/mLib/blobdiff_plain/4ce6f42e899799bff22c1378deaa4a1a7ece7e91..d4efbcd93c940ad522fcf8c601ec1829d2e0b10d:/traceopt.c

diff --git a/traceopt.c b/traceopt.c
index 08cdd57..2d1594f 100644
--- a/traceopt.c
+++ b/traceopt.c
@@ -1,13 +1,13 @@
 /* -*-c-*-
  *
- * $Id: traceopt.c,v 1.1 1999/10/22 22:40:08 mdw Exp $
+ * $Id: traceopt.c,v 1.3 2004/04/08 01:36:13 mdw Exp $
  *
  * Parsing tracing options
  *
  * (c) 1999 Straylight/Edgeware
  */
 
-/*----- Licensing notice --------------------------------------------------* 
+/*----- Licensing notice --------------------------------------------------*
  *
  * This file is part of the mLib utilities library.
  *
@@ -15,26 +15,18 @@
  * it under the terms of the GNU Library General Public License as
  * published by the Free Software Foundation; either version 2 of the
  * License, or (at your option) any later version.
- * 
+ *
  * mLib is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU Library General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Library General Public
  * License along with mLib; if not, write to the Free
  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  * MA 02111-1307, USA.
  */
 
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: traceopt.c,v $
- * Revision 1.1  1999/10/22 22:40:08  mdw
- * Separate function for parsing user trace specs.
- *
- */
-
 /*----- Header files ------------------------------------------------------*/
 
 #include <stdio.h>
@@ -48,7 +40,7 @@
 
 /* --- @traceopt@ --- *
  *
- * Arguments:	@trace_opt *t@ = pointer to trace options table
+ * Arguments:	@const trace_opt *t@ = pointer to trace options table
  *		@const char *p@ = option string supplied by user
  *		@unsigned f@ = initial tracing flags
  *		@unsigned bad@ = forbidden tracing flags
@@ -60,18 +52,20 @@
  *		`?' character, a help message is displayed.
  */
 
-unsigned traceopt(trace_opt *t, const char *p, unsigned f, unsigned bad)
+unsigned traceopt(const trace_opt *t, const char *p,
+		  unsigned f, unsigned bad)
 {
   unsigned sense = 1;
 
   /* --- Dump out help text --- */
 
-  if (!p || strcmp(p, "?")) {
+  if (!p || !strcmp(p, "?")) {
+    const trace_opt *tt;
     puts("Trace options:");
-    while (t->ch) {
-      if (t->f & bad || !t->help)
+    for (tt = t; tt->ch; tt++) {
+      if (!(tt->f & ~bad) || !tt->help)
 	continue;
-      printf("  `%c': %s\n", t->ch, t->help);
+      printf("	`%c': %s\n", tt->ch, tt->help);
     }
     return (f);
   }
@@ -88,17 +82,17 @@ unsigned traceopt(trace_opt *t, const char *p, unsigned f, unsigned bad)
 	sense = 0;
 	break;
       default: {
-	trace_opt *tt;
+	const trace_opt *tt;
 	for (tt = t; tt->ch; tt++) {
-	  if (tt->f & bad)
+	  if (!(tt->f & ~bad))
 	    continue;
 	  if (tt->ch == *p) {
 	    if (sense)
 	      f |= (tt->f & ~bad);
 	    else
 	      f &= ~(tt->f & ~bad);
+	    goto ok;
 	  }
-	  goto ok;
 	}
 	moan("unknown trace option `%c'", *p);
       ok:;