git: 68bff4a07e3f - main - Allow GEOM utilities to specify a -v option.

From: Kirk McKusick <mckusick_at_FreeBSD.org>
Date: Fri, 29 Oct 2021 05:52:24 UTC
The branch main has been updated by mckusick:

URL: https://cgit.FreeBSD.org/src/commit/?id=68bff4a07e3fa6c30a0c0ff6cf5f0bef95dcbd72

commit 68bff4a07e3fa6c30a0c0ff6cf5f0bef95dcbd72
Author:     Kirk McKusick <mckusick@FreeBSD.org>
AuthorDate: 2021-10-29 05:49:48 +0000
Commit:     Kirk McKusick <mckusick@FreeBSD.org>
CommitDate: 2021-10-29 05:50:50 +0000

    Allow GEOM utilities to specify a -v option.
    
    Geom utilities (geli(8), glabel(8), gmirror(8), gpart(8), gmirror(8),
    gmountver(8), etc) all use the geom(8) utility as their back end
    to process their commands and pass them into the kernel. Creating
    a new utility requires no more than filling out a template describing
    the commands and arguments that the utility supports. Consider the
    specification for the very simple gmountver(8) utility:
    
    struct g_command class_commands[] = {
            { "create", G_FLAG_VERBOSE | G_FLAG_LOADKLD, NULL,
                {
                    G_OPT_SENTINEL
                },
                "[-v] prov ..."
            },
            { "destroy", G_FLAG_VERBOSE, NULL,
                {
                    { 'f', "force", NULL, G_TYPE_BOOL },
                    G_OPT_SENTINEL
                },
                "[-fv] name"
            },
            G_CMD_SENTINEL
    };
    
    It has just two commands of its own: "create" and "destroy" along
    with the four standard commands "list", "status", "load", and
    "unload" provided by the base geom(8) utility. The base geom(8)
    utility allows each command to use the G_FLAG_VERBOSE flag to specify
    that a command should accept the -v flag and when the -v flag is
    given the utility prints "Done." if the command completes successfully.
    In the above example, both of the commands set the G_FLAG_VERBOSE,
    so have the -v option available. In addition the "destroy" command
    accepts the -f boolean flag to force the destruction.
    
    If the "destroy" command wanted to also print out verbose information,
    it would need to explicitly declare its intent by adding a line:
    
                    { 'v', "verbose", NULL, G_TYPE_BOOL },
    
    Before this change, the geom utility would silently ignore the above
    line in the configuration file, so it was impossible for the utility
    to know that the -v flag had been set on the command. With this
    change a geom command can explicitly specify a -v option with a
    line as given above and handle it as it would any other option. If
    both a -v option and G_FLAG_VERBOSE are specified for a command
    then both types of verbose information will be output when that
    command is run with -v.
    
    MFC after:    1 week
    Sponsored by: Netflix
---
 sbin/geom/core/geom.c | 19 ++++++++++++-------
 sbin/geom/core/geom.h | 13 +++++++++++++
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/sbin/geom/core/geom.c b/sbin/geom/core/geom.c
index 58b33a067700..2e0d8683df49 100644
--- a/sbin/geom/core/geom.c
+++ b/sbin/geom/core/geom.c
@@ -314,7 +314,7 @@ parse_arguments(struct g_command *cmd, struct gctl_req *req, int *argc,
 	struct g_option *opt;
 	char opts[64];
 	unsigned i;
-	int ch;
+	int ch, vcount;
 
 	*opts = '\0';
 	if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0)
@@ -336,17 +336,22 @@ parse_arguments(struct g_command *cmd, struct gctl_req *req, int *argc,
 	/*
 	 * Add specified arguments.
 	 */
+	vcount = 0;
 	while ((ch = getopt(*argc, *argv, opts)) != -1) {
 		/* Standard (not passed to kernel) options. */
-		switch (ch) {
-		case 'v':
+		if (ch == 'v' && (cmd->gc_flags & G_FLAG_VERBOSE) != 0)
 			verbose = 1;
-			continue;
-		}
 		/* Options passed to kernel. */
 		opt = find_option(cmd, ch);
-		if (opt == NULL)
+		if (opt == NULL) {
+			if (ch == 'v' && (cmd->gc_flags & G_FLAG_VERBOSE) != 0){
+				if (++vcount < 2)
+					continue;
+				else
+					warnx("Option 'v' specified twice.");
+			}
 			usage();
+		}
 		if (!G_OPT_ISMULTI(opt) && G_OPT_ISDONE(opt)) {
 			warnx("Option '%c' specified twice.", opt->go_char);
 			usage();
@@ -440,7 +445,7 @@ set_flags(struct g_command *cmd)
 {
 	unsigned flags = 0;
 
-	if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0 && verbose)
+	if ((cmd->gc_flags & G_FLAG_VERBOSE) != 0)
 		flags |= G_FLAG_VERBOSE;
 
 	return (flags);
diff --git a/sbin/geom/core/geom.h b/sbin/geom/core/geom.h
index 89c5828c6429..38a99032f692 100644
--- a/sbin/geom/core/geom.h
+++ b/sbin/geom/core/geom.h
@@ -32,6 +32,19 @@
 #define	_GEOM_H_
 #define	G_LIB_VERSION	5
 
+/*
+ * The G_FLAG_VERBOSE flag on a command specification means that the
+ * comand will accept a -v option and the GEOM framework will print
+ * out status information after the command when it is run with -v.
+ * Additionally a GEOM command can explicitly specify a -v option and
+ * handle it as it would any other option. If both a -v option and
+ * G_FLAG_VERBOSE are specified for a command then both types of verbose
+ * information will be output when that command is run with -v.
+ *
+ * When the G_FLAG_LOADKLD is specified for a command, the GEOM kernel
+ * module will be loaded when that command is run if it has not yet been
+ * loaded. This flag is typically specified for the `create' command.
+ */
 #define	G_FLAG_NONE	0x0000
 #define	G_FLAG_VERBOSE	0x0001
 #define	G_FLAG_LOADKLD	0x0002