[src/trunk]: src/usr.bin/xlint/xlint Explain the usage errors.

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e5adb22f6a1f
branches:  trunk
changeset: 1026535:e5adb22f6a1f
user:      christos <christos%NetBSD.org@localhost>
date:      Sun Nov 28 02:07:02 2021 +0000

description:
Explain the usage errors.

diffstat:

 usr.bin/xlint/xlint/xlint.c |  54 ++++++++++++++++++++++++++++++--------------
 1 files changed, 37 insertions(+), 17 deletions(-)

diffs (164 lines):

diff -r 92750edce046 -r e5adb22f6a1f usr.bin/xlint/xlint/xlint.c
--- a/usr.bin/xlint/xlint/xlint.c       Sun Nov 28 02:01:30 2021 +0000
+++ b/usr.bin/xlint/xlint/xlint.c       Sun Nov 28 02:07:02 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: xlint.c,v 1.84 2021/11/21 10:39:47 rillig Exp $ */
+/* $NetBSD: xlint.c,v 1.85 2021/11/28 02:07:02 christos Exp $ */
 
 /*
  * Copyright (c) 1996 Christopher G. Demetriou.  All Rights Reserved.
@@ -38,7 +38,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: xlint.c,v 1.84 2021/11/21 10:39:47 rillig Exp $");
+__RCSID("$NetBSD: xlint.c,v 1.85 2021/11/28 02:07:02 christos Exp $");
 #endif
 
 #include <sys/param.h>
@@ -46,6 +46,7 @@
 #include <sys/stat.h>
 #include <sys/utsname.h>
 #include <errno.h>
+#include <stdarg.h>
 #include <fcntl.h>
 #include <paths.h>
 #include <signal.h>
@@ -299,13 +300,20 @@
        return *cp1 == '\0' ? cp2 : cp1;
 }
 
-static void __attribute__((noreturn))
-usage(void)
+static void __attribute__((__noreturn__, __format__(__printf__, 1, 2)))
+usage(const char *fmt, ...)
 {
        const char *name;
        int indent;
+       va_list ap;
 
        name = getprogname();
+       fprintf(stderr, "%s: ", name);
+       va_start(ap, fmt);
+       vfprintf(stderr, fmt, ap);
+       va_end(ap);
+       fprintf(stderr, "\n");
+
        indent = (int)(strlen("usage: ") + strlen(name));
        (void)fprintf(stderr,
            "usage: %s [-abceghprvwxzHFST] [-s|-t] [-i|-nu]\n"
@@ -412,7 +420,8 @@
 
                case 'i':
                        if (Cflag)
-                               usage();
+                               usage("%c and %s flags cannot be specified "
+                                   "together", 'C', "i");
                        iflag = true;
                        break;
 
@@ -430,7 +439,8 @@
 
                case 's':
                        if (tflag)
-                               usage();
+                               usage("%c and %s flags cannot be specified "
+                                   "together", 's', "t");
                        list_clear(&cpp.lcflags);
                        list_add(&cpp.lcflags, "-trigraphs");
                        list_add(&cpp.lcflags, "-Wtrigraphs");
@@ -443,7 +453,8 @@
 
                case 'S':
                        if (tflag)
-                               usage();
+                               usage("%c and %s flags cannot be specified "
+                                   "together", 'S', "t");
                        pass_flag_to_lint1(c);
                        break;
 
@@ -455,7 +466,8 @@
 #if !HAVE_NBTOOL_CONFIG_H
                case 't':
                        if (sflag)
-                               usage();
+                               usage("%c and %s flags cannot be specified "
+                                   "together", 's', "t");
                        tflag = true;
                        list_clear(&cpp.lcflags);
                        list_add(&cpp.lcflags, "-traditional");
@@ -473,8 +485,13 @@
                        break;
 
                case 'C':
-                       if (Cflag || oflag || iflag)
-                               usage();
+                       if (Cflag)
+                               usage("%c flag already specified", 'C');
+                       usage("%c and %s flags cannot be specified "
+                           "together", 'C', "o or i");
+                       if (oflag || iflag)
+                               usage("%c and %s flags cannot be specified "
+                                   "together", 'C', "o or i");
                        Cflag = true;
                        pass_flag_to_lint2(c);
                        pass_to_lint2(optarg);
@@ -484,7 +501,7 @@
 
                case 'd':
                        if (dflag)
-                               usage();
+                               usage("%c flag already specified", 'd');
                        dflag = true;
                        pass_to_cpp("-nostdinc");
                        pass_to_cpp("-isystem");
@@ -504,8 +521,11 @@
                        break;
 
                case 'o':
-                       if (Cflag || oflag)
-                               usage();
+                       if (oflag)
+                               usage("%c flag already specified", 'o');
+                       if (Cflag)
+                               usage("%c and %s flags cannot be specified "
+                                   "together", 'C', "o");
                        oflag = true;
                        outputfn = xstrdup(optarg);
                        break;
@@ -527,7 +547,7 @@
                        break;
 
                default:
-                       usage();
+                       usage("Unknown flag %c", c);
                        /* NOTREACHED */
                }
        }
@@ -553,7 +573,7 @@
                        else if (arg[1] == 'L')
                                list = &libsrchpath;
                        else {
-                               usage();
+                               usage("Unknown argument %s", arg);
                                /* NOTREACHED */
                        }
 
@@ -563,7 +583,7 @@
                                argc--;
                                list_add(list, *++argv);
                        } else
-                               usage();
+                               usage("Missing argument for l or L");
                } else {
                        /* filename */
                        fname(arg);
@@ -574,7 +594,7 @@
        }
 
        if (first)
-               usage();
+               usage("Missing filename");
 
        if (iflag)
                terminate(0);