[PATCH] common: env: make error message more verbose

[Sascha Hauer]

On Tue, Apr 28, 2015 at 12:32:27PM +0200, Steffen Trumtrar wrote:
> Change the setenv error message from
> 
> 	set parameter: Invalid argument
> 
> to a more helpful
> 
> 	net: cannot set parameter 'nameserver': Invalid argument
> 
> Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
> ---
>  common/env.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/common/env.c b/common/env.c
> index 2e33eb35856b..434170a7468b 100644
> --- a/common/env.c
> +++ b/common/env.c
> @@ -225,8 +225,10 @@ int setenv(const char *_name, const char *value)
>  
>  		errno = -ret;
>  
> -		if (ret < 0)
> -			perror("set parameter");
> +		if (ret < 0) {
> +			dev_err(dev, "cannot set parameter '%s'", par);
> +			perror("");
> +		}

dev may be invalid here, so you shouldn't use dev_err.

After we talked about the missing informations in the setenv failure
path I created the following patch. I applied this one now.

Sascha

------------------------8<---------------------------

>From 6d4afd96fc94a3f2d256ef4e8d7c9687a145a701 Mon Sep 17 00:00:00 2001
From: Sascha Hauer <s.hauer at pengutronix.de>
Date: Tue, 28 Apr 2015 12:43:02 +0200
Subject: [PATCH] setenv: Be more informative when device parameter setting
 fails

When setting a device parameter fails not only the error code
is of interest, but also what the parameter name is, what the
device name is and whether a device was found for this name.
Add this information to the error message.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 common/env.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/common/env.c b/common/env.c
index 2e33eb3..c98ed73 100644
--- a/common/env.c
+++ b/common/env.c
@@ -218,16 +218,18 @@ int setenv(const char *_name, const char *value)
 
 		*par++ = 0;
 		dev = get_device_by_name(name);
-		if (dev)
+		if (dev) {
 			ret = dev_set_param(dev, par, value);
-		else
+			if (ret)
+				eprintf("%s: set parameter %s: %s\n",
+						dev_name(dev), par, strerror(-ret));
+		} else {
 			ret = -ENODEV;
+			eprintf("set parameter: no such device %s\n", name);
+		}
 
 		errno = -ret;
 
-		if (ret < 0)
-			perror("set parameter");
-
 		goto out;
 	}
 
-- 
2.1.4

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