Add an -a flag to getconf.

When -a is specified, the name and value of all system or path
configuration values is reported to standard output.

Reviewed by:	kib (earlier version)
MFC after:	1 week
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D12373

usr.bin/getconf/confstr.gperf

@@ -68,3 +68,14 @@ find_confstr(const char *name, int *key)
 	}
 	return 0;
 }
+
+void
+foreach_confstr(void (*func)(const char *, int))
+{
+	const struct map *mp;
+
+	for (mp = wordlist; mp->name != NULL; mp++) {
+		if (mp->valid)
+			func(mp->name, mp->key);
+	}
+}

usr.bin/getconf/getconf.1

@@ -28,7 +28,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd August 8, 2016
+.Dd September 15, 2017
 .Dt GETCONF 1
 .Os
 .Sh NAME
@@ -36,6 +36,9 @@
 .Nd retrieve standard configuration variables
 .Sh SYNOPSIS
 .Nm
+.Fl a
+.Op Ar file
+.Nm
 .Op Fl v Ar environment
 .Ar path_var
 .Ar file
@@ -45,20 +48,35 @@
 .Sh DESCRIPTION
 The
 .Nm
-utility prints the value of a
+utility prints the values of
 .Tn POSIX
 or
 .Tn X/Open
-path or system configuration variable to the standard output.
-If the specified variable is undefined, the string
+path or system configuration variables to the standard output.
+If a variable is undefined, the string
 .Dq Li undefined
 is output.
 .Pp
-The first form of the command, with two mandatory
+The first form of the command displays all of the path or system configuration
+variables to standard output.
+If
+.Ar file
+is provided,
+all path configuration variables are reported for
+.Ar file
+using
+.Xr pathconf 2 .
+Otherwise,
+all system configuration variables are reported using
+.Xr confstr 3
+and
+.Xr sysconf 3.
+.Pp
+The second form of the command, with two mandatory
 arguments, retrieves file- and file system-specific
 configuration variables using
 .Xr pathconf 2 .
-The second form, with a single argument, retrieves system
+The third form, with a single argument, retrieves system
 configuration variables using
 .Xr confstr 3
 and

usr.bin/getconf/getconf.c

@@ -34,6 +34,7 @@ __FBSDID("$FreeBSD$");
 
 #include <err.h>
 #include <errno.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sysexits.h>
@@ -41,6 +42,8 @@ __FBSDID("$FreeBSD$");
 
 #include "getconf.h"
 
+static void	do_allsys(void);
+static void	do_allpath(const char *path);
 static void	do_confstr(const char *name, int key);
 static void	do_sysconf(const char *name, int key);
 static void	do_pathconf(const char *name, int key, const char *path);
@@ -49,7 +52,8 @@ static void
 usage(void)
 {
 	fprintf(stderr,
-"usage: getconf [-v prog_env] system_var\n"
+"usage: getconf -a [pathname]\n"
+"       getconf [-v prog_env] system_var\n"
 "       getconf [-v prog_env] path_var pathname\n");
 	exit(EX_USAGE);
 }
@@ -57,13 +61,18 @@ usage(void)
 int
 main(int argc, char **argv)
 {
+	bool aflag;
 	int c, key, valid;
 	const char *name, *vflag, *alt_path;
 	intmax_t limitval;
 
+	aflag = false;
 	vflag = NULL;
-	while ((c = getopt(argc, argv, "v:")) != -1) {
+	while ((c = getopt(argc, argv, "av:")) != -1) {
 		switch (c) {
+		case 'a':
+			aflag = true;
+			break;
 		case 'v':
 			vflag = optarg;
 			break;
@@ -73,6 +82,16 @@ main(int argc, char **argv)
 		}
 	}
 
+	if (aflag) {
+		if (vflag != NULL)
+			usage();
+		if (argv[optind] == NULL)
+			do_allsys();
+		else
+			do_allpath(argv[optind]);
+		return (0);
+	}
+
 	if ((name = argv[optind]) == NULL)
 		usage();
 
@@ -135,6 +154,77 @@ main(int argc, char **argv)
 	return 0;
 }
 
+static void
+do_onestr(const char *name, int key)
+{
+	size_t len;
+
+	errno = 0;
+	len = confstr(key, 0, 0);
+	if (len == 0 && errno != 0) {
+		warn("confstr: %s", name);
+		return;
+	}
+	printf("%s: ", name);
+	if (len == 0)
+		printf("undefined\n");
+	else {
+		char buf[len + 1];
+
+		confstr(key, buf, len);
+		printf("%s\n", buf);
+	}
+}
+
+static void
+do_onesys(const char *name, int key)
+{
+	long value;
+
+	errno = 0;
+	value = sysconf(key);
+	if (value == -1 && errno != 0) {
+		warn("sysconf: %s", name);
+		return;
+	}
+	printf("%s: ", name);
+	if (value == -1)
+		printf("undefined\n");
+	else
+		printf("%ld\n", value);
+}
+
+static void
+do_allsys(void)
+{
+
+	foreach_confstr(do_onestr);
+	foreach_sysconf(do_onesys);
+}
+
+static void
+do_onepath(const char *name, int key, const char *path)
+{
+	long value;
+
+	errno = 0;
+	value = pathconf(path, key);
+	if (value == -1 && errno != EINVAL && errno != 0)
+		warn("pathconf: %s", name);
+	printf("%s: ", name);
+	if (value == -1)
+		printf("undefined\n");
+	else
+		printf("%ld\n", value);
+}
+
+static void
+do_allpath(const char *path)
+{
+
+	foreach_pathconf(do_onepath, path);
+}
+
 static void
 do_confstr(const char *name, int key)
 {

usr.bin/getconf/getconf.h

@@ -41,3 +41,7 @@ int	find_limit(const char *name, intmax_t *value);
 int	find_pathconf(const char *name, int *key);
 int	find_progenv(const char *name, const char **alt_path);
 int	find_sysconf(const char *name, int *key);
+void	foreach_confstr(void (*func)(const char *, int));
+void	foreach_pathconf(void (*func)(const char *, int, const char *),
+	    const char *path);
+void	foreach_sysconf(void (*func)(const char *, int));

usr.bin/getconf/pathconf.gperf

@@ -68,3 +68,15 @@ find_pathconf(const char *name, int *key)
 	}
 	return 0;
 }
+
+void
+foreach_pathconf(void (*func)(const char *, int, const char *),
+    const char *path)
+{
+	const struct map *mp;
+
+	for (mp = wordlist; mp->name != NULL; mp++) {
+		if (mp->valid)
+			func(mp->name, mp->key, path);
+	}
+}

usr.bin/getconf/sysconf.gperf

@@ -147,3 +147,14 @@ find_sysconf(const char *name, int *key)
 	}
 	return 0;
 }
+
+void
+foreach_sysconf(void (*func)(const char *, int))
+{
+	const struct map *mp;
+
+	for (mp = wordlist; mp->name != NULL; mp++) {
+		if (mp->valid)
+			func(mp->name, mp->key);
+	}
+}