Chuck Lever wrote: > Hi Bian > > On Nov 29, 2010, at 9:05 PM, Bian Naimeng wrote: > >> >> Steve Dickson wrote: >>> 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? >>> >> Actually, there's no problem now. But this's not a good style, po_destroy >> maybe change the errno later on such as adding a printf. >> So if somebady want modify the po_destroy, he must be careful of it. :) >> >> And, i don't think it's a good idea that explicitly set errno, it maybe make >> some trouble in the future. It's better returning error in nfs_do_mount_v3v2, >> or save the error in a input parameter. :) > > Perhaps it isn't good style, but I'd rather see all of stropts.c updated to pass errno as an explicit parameter than to have it changed piecemeal. I agree that we run into trouble everywhere in mount with errno. > > I think this particular patch is unnecessary until we have a need for it. Basically it confuses a reviewer who sees that we've gone to the trouble here to save and restore errno, but nowhere else, and besides po_destroy() doesn't even alter errno. Why are we bothering? > Well, it's okay to me. Thanks Bian >>> steved. >>> >>>>> Signed-off-by: Bian Naimeng <biannm@xxxxxxxxxxxxxx> >>>>> Signed-off-by: Mi Jinlong <mijinlong@xxxxxxxxxxxxxx> >>>>> --- >>>>> 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 >>>>> >>>>> >>>>> -- >>>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >>>>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> >> -- >> Regards >> Bian Naimeng >> > -- Regards Bian Naimeng -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html