libs/libc/unistd: Make optarg, optind, opterr and optopt variables.

include/unistd.h

@@ -289,12 +289,19 @@
 #define getdtablesize(f)                 ((int)sysconf(_SC_OPEN_MAX))
 #define getpagesize(f)                   ((int)sysconf(_SC_PAGESIZE))
 
-/* Accessor functions associated with getopt(). */
+/* Accessor functions associated with getopt().  In the user space of a
+ * kernel build every process has its own copy of the C library data, so
+ * optarg, opterr, optind and optopt are the plain variables that POSIX
+ * specifies (see below).  Programs that bring their own getopt() depend
+ * on that.
+ */
 
-#define optarg                           (*(getoptargp()))
-#define opterr                           (*(getopterrp()))
-#define optind                           (*(getoptindp()))
-#define optopt                           (*(getoptoptp()))
+#if !defined(CONFIG_BUILD_KERNEL) || defined(__KERNEL__)
+#  define optarg                         (*(getoptargp()))
+#  define opterr                         (*(getopterrp()))
+#  define optind                         (*(getoptindp()))
+#  define optopt                         (*(getoptoptp()))
+#endif
 
 #if defined(CONFIG_FS_LARGEFILE)
 #  define lseek64                        lseek
@@ -481,6 +488,13 @@ FAR int   *getopterrp(void);  /* Print error message */
 FAR int   *getoptindp(void);  /* Index into argv */
 FAR int   *getoptoptp(void);  /* Unrecognized option character */
 
+#if defined(CONFIG_BUILD_KERNEL) && !defined(__KERNEL__)
+EXTERN FAR char *optarg;      /* Optional argument following option */
+EXTERN int       opterr;      /* Print error message */
+EXTERN int       optind;      /* Index into argv */
+EXTERN int       optopt;      /* Unrecognized option character */
+#endif
+
 int     gethostname(FAR char *name, size_t namelen);
 int     sethostname(FAR const char *name, size_t namelen);
 

libs/libc/unistd/CMakeLists.txt

@@ -37,6 +37,7 @@ set(SRCS
     lib_getopterrp.c
     lib_getoptindp.c
     lib_getoptoptp.c
+    lib_getoptpublic.c
     lib_times.c
     lib_alarm.c
     lib_fstatvfs.c

libs/libc/unistd/Make.defs

@@ -25,7 +25,7 @@
 CSRCS += lib_access.c lib_daemon.c lib_swab.c lib_pathconf.c lib_sysconf.c
 CSRCS += lib_getcwd.c lib_getentropy.c lib_getopt_common.c lib_getopt.c
 CSRCS += lib_getopt_long.c lib_getopt_longonly.c lib_getoptvars.c lib_getoptargp.c
-CSRCS += lib_getopterrp.c lib_getoptindp.c lib_getoptoptp.c lib_times.c
+CSRCS += lib_getopterrp.c lib_getoptindp.c lib_getoptoptp.c lib_getoptpublic.c lib_times.c
 CSRCS += lib_alarm.c lib_fstatvfs.c lib_statvfs.c lib_sleep.c lib_nice.c
 CSRCS += lib_getrusage.c lib_utime.c lib_utimes.c
 CSRCS += lib_setrlimit.c lib_getrlimit.c lib_setpriority.c lib_getpriority.c

libs/libc/unistd/lib_getopt_common.c

@@ -167,20 +167,20 @@ static int getopt_long_option(FAR struct getopt_s *go,
                 {
                   FAR char *next;
 
-                  case no_argument:
-                    /* No, no arguments. Just return the argument that we
-                     * found.
-                     */
+                  /* No, no arguments. Just return the argument that we
+                   * found.
+                   */
 
+                  case no_argument:
                     go->go_optptr = NULL;
                     go->go_optind++;
                     break;
 
-                  case optional_argument:
-                    /* Check if there is a following argument and if that
-                     * following argument is another option.
-                     */
+                  /* Check if there is a following argument and if that
+                   * following argument is another option.
+                   */
 
+                  case optional_argument:
                     next = argv[go->go_optind + 1];
                     if (next == NULL || next[0] == '-')
                       {
@@ -334,17 +334,26 @@ static int getopt_long_option(FAR struct getopt_s *go,
  *
  ****************************************************************************/
 
+#ifdef GETOPT_PUBLIC_VARIABLES
+static int getopt_internal(int argc, FAR char * const argv[],
+                           FAR const char *optstring,
+                           FAR const struct option *longopts,
+                           FAR int *longindex,
+                           enum getopt_mode_e mode)
+#else
 int getopt_common(int argc, FAR char * const argv[],
                   FAR const char *optstring,
                   FAR const struct option *longopts,
                   FAR int *longindex,
                   enum getopt_mode_e mode)
+#endif
 {
   int ret;
 
   /* Get thread-specific getopt() variables */
 
   FAR struct getopt_s *go = getoptvars();
+
   if (go == NULL)
     {
       return '?';
@@ -640,3 +649,31 @@ int getopt_common(int argc, FAR char * const argv[],
   go->go_binitialized = false;
   return ERROR;
 }
+
+#ifdef GETOPT_PUBLIC_VARIABLES
+int getopt_common(int argc, FAR char * const argv[],
+                  FAR const char *optstring,
+                  FAR const struct option *longopts,
+                  FAR int *longindex,
+                  enum getopt_mode_e mode)
+{
+  FAR struct getopt_s *go = getoptvars();
+  int ret;
+
+  /* The program may have set optind (to restart) or opterr */
+
+  go->go_optarg = optarg;
+  go->go_opterr = opterr;
+  go->go_optind = optind;
+  go->go_optopt = optopt;
+
+  ret = getopt_internal(argc, argv, optstring, longopts, longindex, mode);
+
+  optarg = go->go_optarg;
+  opterr = go->go_opterr;
+  optind = go->go_optind;
+  optopt = go->go_optopt;
+
+  return ret;
+}
+#endif

libs/libc/unistd/lib_getoptargp.c

@@ -43,6 +43,11 @@
 
 FAR char **getoptargp(void)
 {
+#ifdef GETOPT_PUBLIC_VARIABLES
+  return &optarg;
+#else
   FAR struct getopt_s *go = getoptvars();
+
   return &go->go_optarg;
+#endif
 }

libs/libc/unistd/lib_getopterrp.c

@@ -43,6 +43,11 @@
 
 FAR int *getopterrp(void)
 {
+#ifdef GETOPT_PUBLIC_VARIABLES
+  return &opterr;
+#else
   FAR struct getopt_s *go = getoptvars();
+
   return &go->go_opterr;
+#endif
 }

libs/libc/unistd/lib_getoptindp.c

@@ -43,6 +43,11 @@
 
 int *getoptindp(void)
 {
+#ifdef GETOPT_PUBLIC_VARIABLES
+  return &optind;
+#else
   FAR struct getopt_s *go = getoptvars();
+
   return &go->go_optind;
+#endif
 }

libs/libc/unistd/lib_getoptoptp.c

@@ -43,6 +43,11 @@
 
 int *getoptoptp(void)
 {
+#ifdef GETOPT_PUBLIC_VARIABLES
+  return &optopt;
+#else
   FAR struct getopt_s *go = getoptvars();
+
   return &go->go_optopt;
+#endif
 }

libs/libc/unistd/lib_getoptpublic.c

@@ -0,0 +1,52 @@
+/****************************************************************************
+ * libs/libc/unistd/lib_getoptpublic.c
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include "unistd.h"
+
+#ifdef GETOPT_PUBLIC_VARIABLES
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/* The public getopt() variables of a kernel-build process.  They are in a
+ * file of their own, so that a program that defines its own does not get
+ * a second definition from the C library.
+ * getopt_common() copies them to and from its internal state.
+ */
+
+FAR char *optarg;
+int opterr = 1;
+int optind = 1;
+int optopt = '?';
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+#endif /* GETOPT_PUBLIC_VARIABLES */

libs/libc/unistd/unistd.h

@@ -66,6 +66,14 @@ extern "C"
  * getopt_long_only() that is being emulated by getopt_common().
  */
 
+/* In the user space of a kernel build, the public getopt() variables are
+ * plain variables (see include/unistd.h).
+ */
+
+#if defined(CONFIG_BUILD_KERNEL) && !defined(__KERNEL__)
+#  define GETOPT_PUBLIC_VARIABLES 1
+#endif
+
 enum getopt_mode_e
 {
   GETOPT_MODE           = 0,