From 15f7918ff432d5da2b2abc84a50c685bde5e72ef Mon Sep 17 00:00:00 2001
From: Jens Axboe <jens.axboe@oracle.com>
Date: Wed, 10 Jan 2007 12:26:18 +0100
Subject: [PATCH] [PATCH] Show allowed option values for string matching

Helpful to avoid looking in the documentation.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
 init.c  | 19 +++++++++++++++----
 parse.c | 34 ++++++++++++++++++++++++++++++++++
 parse.h |  1 +
 3 files changed, 50 insertions(+), 4 deletions(-)

diff --git a/init.c b/init.c
index 37b84e68..11fd3e28 100644
--- a/init.c
+++ b/init.c
@@ -63,29 +63,35 @@ static struct fio_option options[] = {
 		.name	= "rw",
 		.type	= FIO_OPT_STR,
 		.cb	= str_rw_cb,
-		.help	= "IO direction (read, write, rw, etc)",
+		.help	= "IO direction",
 		.def	= "read",
+		.posval	= { "read", "write", "randwrite", "randread", "rw",
+				"randrw", },
 	},
 	{
 		.name	= "ioengine",
 		.type	= FIO_OPT_STR,
 		.cb	= str_ioengine_cb,
-		.help	= "IO engine to use (sync, aio, etc)",
+		.help	= "IO engine to use",
 		.def	= "sync",
+		.posval	= { "sync", "libaio", "posixaio", "mmap", "splice",
+				"sg", "null", },
 	},
 	{
 		.name	= "mem",
 		.type	= FIO_OPT_STR,
 		.cb	= str_mem_cb,
-		.help	= "Backing type for IO buffers (malloc, shm, etc)",
+		.help	= "Backing type for IO buffers",
 		.def	= "malloc",
+		.posval	=  { "malloc", "shm", "shmhuge", "mmap", "mmaphuge", },
 	},
 	{
 		.name	= "verify",
 		.type	= FIO_OPT_STR,
 		.cb	= str_verify_cb,
-		.help	= "Verify sum function (md5 or crc32)",
+		.help	= "Verify sum function",
 		.def	= "0",
+		.posval	= { "crc32", "md5", },
 	},
 	{
 		.name	= "write_iolog",
@@ -226,6 +232,7 @@ static struct fio_option options[] = {
 		.type	= FIO_OPT_INT,
 		.off1	= td_var_offset(nice),
 		.help	= "Set job CPU nice value",
+		.minval	= -19,
 		.maxval	= 20,
 		.def	= "0",
 	},
@@ -235,12 +242,16 @@ static struct fio_option options[] = {
 		.type	= FIO_OPT_INT,
 		.cb	= str_prio_cb,
 		.help	= "Set job IO priority value",
+		.minval	= 0,
+		.maxval	= 7,
 	},
 	{
 		.name	= "prioclass",
 		.type	= FIO_OPT_INT,
 		.cb	= str_prioclass_cb,
 		.help	= "Set job IO priority class",
+		.minval	= 0,
+		.maxval	= 3,
 	},
 #endif
 	{
diff --git a/parse.c b/parse.c
index 2e8a2a52..5347f675 100644
--- a/parse.c
+++ b/parse.c
@@ -366,6 +366,38 @@ int parse_option(const char *opt, struct fio_option *options, void *data)
 	return 1;
 }
 
+static void show_option_range(struct fio_option *o)
+{
+	if (!o->minval && !o->maxval)
+		return;
+
+	printf("%16s: min=%d, max=%d\n", "range", o->minval, o->maxval);
+}
+
+static void show_option_values(struct fio_option *o)
+{
+	const char *msg;
+	int i = 0;
+
+	if (!o->posval)
+		return;
+
+	do {
+		msg = o->posval[i];
+		if (!msg)
+			break;
+
+		if (!i)
+			printf("%16s: ", "valid values");
+
+		printf("%s,", msg);
+		i++;
+	} while (1);
+
+	if (i)
+		printf("\n");
+}
+
 int show_cmd_help(struct fio_option *options, const char *name)
 {
 	int show_all = !strcmp(name, "all");
@@ -391,6 +423,8 @@ int show_cmd_help(struct fio_option *options, const char *name)
 			if (match) {
 				printf("%16s: %s\n", "type", typehelp[o->type]);
 				printf("%16s: %s\n", "default", o->def ? o->def : "no default");
+				show_option_range(o);
+				show_option_values(o);
 			}
 		}
 
diff --git a/parse.h b/parse.h
index edba7fc6..3e3c9d9f 100644
--- a/parse.h
+++ b/parse.h
@@ -30,6 +30,7 @@ struct fio_option {
 	void *cb;			/* callback */
 	const char *help;		/* help text for option */
 	const char *def;		/* default setting */
+	const char *posval[16];		/* possible values */
 };
 
 typedef int (str_cb_fn)(void *, char *);
-- 
2.25.1