Re: [PATCH] mount: avoid po_destroy to modify errno what we really want

[Steve Dickson <SteveD@redhat.com>]

On 11/29/2010 09:45 AM, Chuck Lever wrote:
> 
> On Nov 25, 2010, at 5:07 AM, Mi Jinlong wrote:
> 
>> We should return the errno that was set before po_destroy,
>> rather than the errno that was set at po_destroy.
>>
>> Because the po_destroy function don't affect the return value,
>> this patch just revert the saved errno after po_destroy.
> 
> The only library function used in po_destroy() is free(3).  
> Does free(3) change the value of errno?
Looking at the man page and taking a look a the 
glibc code it appears the answer is no. free(3)
does not set errno.

Bian, what was the problem you were seeing that this
patch fixed? 

steved.

> 
>> Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
>> Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
>> ---
>> utils/mount/stropts.c |    8 ++++++--
>> 1 files changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
>> index 50a1a2a..d554877 100644
>> --- a/utils/mount/stropts.c
>> +++ b/utils/mount/stropts.c
>> @@ -592,7 +592,7 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>> 		struct sockaddr *sap, socklen_t salen)
>> {
>> 	struct mount_options *options = po_dup(mi->options);
>> -	int result = 0;
>> +	int result = 0, save = 0;
>>
>> 	if (!options) {
>> 		errno = ENOMEM;
>> @@ -637,7 +637,9 @@ static int nfs_do_mount_v3v2(struct nfsmount_info *mi,
>> 	result = nfs_sys_mount(mi, options);
>>
>> out_fail:
>> +	save = errno;
>> 	po_destroy(options);
>> +	errno = save;
>> 	return result;
>> }
>>
>> @@ -673,7 +675,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>> 		struct sockaddr *sap, socklen_t salen)
>> {
>> 	struct mount_options *options = po_dup(mi->options);
>> -	int result = 0;
>> +	int result = 0, save = 0;
>>
>> 	if (!options) {
>> 		errno = ENOMEM;
>> @@ -724,7 +726,9 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
>> 	result = nfs_sys_mount(mi, options);
>>
>> out_fail:
>> +	save = errno;
>> 	po_destroy(options);
>> +	errno = save;
>> 	return result;
>> }
>>
>> -- 
>> 1.7.3.2
>>
>>
>> --
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>