devshr: fix wstat, style

- same problem with wstat, if we error then owner has been already updated...
- avoid smalloc while holding qlock in wstat, do it before
- pikeshedd style...

diff --git a/sys/src/9/port/devshr.c b/sys/src/9/port/devshr.c
index 35e73629b7123a90ade4480357131e842a02a0fd..03739a31de39bd846757561c69ab7b122411ff26 100644 (file)
--- a/sys/src/9/port/devshr.c
+++ b/sys/src/9/port/devshr.c
@@ -89,7 +89,7 @@ putmpt(Mpt *mpt)
 {
        if(decref(mpt))
                return;
-       if(mpt->m.to)
+       if(mpt->m.to != nil)
                cclose(mpt->m.to);
        free(mpt->name);
        free(mpt->owner);
@@ -148,9 +148,9 @@ shrclone(Chan *c)
        nc = devclone(c);
        sch = smalloc(sizeof(*sch));
        memmove(sch, och, sizeof(*sch));
-       if(sch->shr)
+       if(sch->shr != nil)
                incref(sch->shr);
-       if(sch->mpt)
+       if(sch->mpt != nil)
                incref(sch->mpt);
        sch->chan = nc;
        nc->aux = sch;
@@ -165,9 +165,9 @@ shrclunk(Chan *c)
        sch = tosch(c);
        c->aux = nil;
        sch->chan = nil;
-       if(sch->mpt)
+       if(sch->mpt != nil)
                putmpt(sch->mpt);
-       if(sch->shr)
+       if(sch->shr != nil)
                putshr(sch->shr);
        free(sch);      
 }
@@ -226,7 +226,7 @@ shrwalk(Chan *c, Chan *nc, char **name, int nname)
                        sch->shr = nil;
                } else if(sch->level == Qcroot || sch->level == Qroot) {
                        qlock(&shrslk);
-                       for(shr = shrs; shr; shr = shr->next)
+                       for(shr = shrs; shr != nil; shr = shr->next)
                                if(strcmp(nam, shr->name) == 0){
                                        incref(shr);
                                        break;
@@ -242,7 +242,7 @@ shrwalk(Chan *c, Chan *nc, char **name, int nname)
                        shr = sch->shr;
                        h = &shr->umh;
                        rlock(&h->lock);
-                       for(m = h->mount; m; m = m->next){
+                       for(m = h->mount; m != nil; m = m->next){
                                mpt = tompt(m);
                                if(strcmp(nam, mpt->name) == 0){
                                        incref(mpt);
@@ -259,7 +259,7 @@ shrwalk(Chan *c, Chan *nc, char **name, int nname)
                        h = &shr->umh;
                        wq2 = nil;
                        rlock(&h->lock);
-                       for(m = h->mount; m && wq2 == nil; m = m->next){
+                       for(m = h->mount; m != nil && wq2 == nil; m = m->next){
                                if(m->to == nil)
                                        continue;
                                if(waserror())
@@ -302,7 +302,7 @@ shrgen(Chan *c, char*, Dirtab*, int, int s, Dir *dp)
        case Qroot:
        case Qcroot:
                qlock(&shrslk);
-               for(shr = shrs; shr && s; shr = shr->next)
+               for(shr = shrs; shr != nil && s > 0; shr = shr->next)
                        s--;
                if(shr == nil){
                        qunlock(&shrslk);
@@ -321,7 +321,7 @@ shrgen(Chan *c, char*, Dirtab*, int, int s, Dir *dp)
                shr = sch->shr;
                h = &shr->umh;
                rlock(&h->lock);
-               for(m = h->mount; m && s; m = m->next)
+               for(m = h->mount; m != nil && s > 0; m = m->next)
                        s--;
                if(m == nil){
                        runlock(&h->lock);
@@ -469,7 +469,7 @@ shrcreate(Chan *c, char *name, int omode, ulong perm)
                        qunlock(&shrslk);
                        nexterror();
                }
-               for(shr = shrs; shr; shr = shr->next)
+               for(shr = shrs; shr != nil; shr = shr->next)
                        if(strcmp(name, shr->name) == 0)
                                error(Eexist);
 
@@ -494,7 +494,7 @@ shrcreate(Chan *c, char *name, int omode, ulong perm)
        case Qcshr:
                if(up->pgrp->noattach)
                        error(Enoattach);
-               if((perm & DMDIR) || openmode(omode) != OWRITE)
+               if((perm & DMDIR) != 0 || openmode(omode) != OWRITE)
                        error(Eperm);
 
                shr = sch->shr;
@@ -511,7 +511,7 @@ shrcreate(Chan *c, char *name, int omode, ulong perm)
                        wunlock(&h->lock);
                        nexterror();
                }
-               for(m = h->mount; m; m = m->next){
+               for(m = h->mount; m != nil; m = m->next){
                        mpt = tompt(m);
                        if(strcmp(name, mpt->name) == 0)
                                error(Eexist);
@@ -574,13 +574,13 @@ shrremove(Chan *c)
                h = &shr->umh;
                qlock(&shrslk);
                rlock(&h->lock);
-               if(h->mount){
+               if(h->mount != nil){
                        runlock(&h->lock);
                        qunlock(&shrslk);
                        error("directory not empty");
                }
                runlock(&h->lock);
-               for(sl = &shrs; *sl; sl = &((*sl)->next))
+               for(sl = &shrs; *sl != nil; sl = &((*sl)->next))
                        if(*sl == shr){
                                *sl = shr->next;
                                shr->next = nil;
@@ -594,7 +594,7 @@ shrremove(Chan *c)
                m = &mpt->m;
                h = &shr->umh;
                wlock(&h->lock);
-               for(ml = &h->mount; *ml; ml = &((*ml)->next))
+               for(ml = &h->mount; *ml != nil; ml = &((*ml)->next))
                        if(*ml == m){
                                *ml = m->next;
                                m->next = nil;
@@ -618,6 +618,15 @@ shrwstat(Chan *c, uchar *dp, int n)
        Ent *ent;
        Dir d;
 
+       strs = smalloc(n);
+       if(waserror()){
+               free(strs);
+               nexterror();
+       }
+       n = convM2D(dp, n, &d, strs);
+       if(n == 0)
+               error(Eshortstat);
+
        h = nil;
        sch = tosch(c);
        switch(sch->level){
@@ -645,27 +654,17 @@ shrwstat(Chan *c, uchar *dp, int n)
        if(strcmp(ent->owner, up->user) && !iseve())
                error(Eperm);
 
-       strs = smalloc(n);
-       if(waserror()){
-               free(strs);
-               nexterror();
-       }
-       n = convM2D(dp, n, &d, strs);
-       if(n == 0)
-               error(Eshortstat);
        if(d.mode != ~0UL)
                ent->perm = d.mode & 0777;
-       if(d.uid && *d.uid)
-               kstrdup(&ent->owner, d.uid);
-       if(d.name && *d.name && strcmp(ent->name, d.name) != 0) {
+       if(d.name != nil && *d.name && strcmp(ent->name, d.name) != 0) {
                if(strchr(d.name, '/') != nil)
                        error(Ebadchar);
                if(strlen(d.name) >= sizeof(up->genbuf))
                        error(Etoolong);
                kstrdup(&ent->name, d.name);
        }
-       poperror();
-       free(strs);
+       if(d.uid != nil && *d.uid)
+               kstrdup(&ent->owner, d.uid);
 
        switch(sch->level){
        case Qcshr:
@@ -677,6 +676,10 @@ shrwstat(Chan *c, uchar *dp, int n)
                wunlock(&h->lock);
                break;
        }
+
+       poperror();
+       free(strs);
+
        return n;
 }
 
@@ -771,7 +774,7 @@ shrwrite(Chan *c, void *va, long n, vlong)
        m->to = c0;
        wunlock(&h->lock);
 
-       if(bc)
+       if(bc != nil)
                cclose(bc);
 
        return n;
@@ -810,7 +813,7 @@ Dev shrdevtab = {
 static void
 chowner(Ent *ent, char *old, char *new)
 {
-       if(ent->owner!=nil && strcmp(old, ent->owner)==0)
+       if(ent->owner != nil && strcmp(old, ent->owner) == 0)
                kstrdup(&ent->owner, new);
 }
 
@@ -821,9 +824,9 @@ shrrenameuser(char *old, char *new)
        Mount *m;
 
        qlock(&shrslk);
-       for(shr = shrs; shr; shr = shr->next){
+       for(shr = shrs; shr != nil; shr = shr->next){
                wlock(&shr->umh.lock);
-               for(m = shr->umh.mount; m; m = m->next)
+               for(m = shr->umh.mount; m != nil; m = m->next)
                        chowner(tompt(m), old, new);
                wunlock(&shr->umh.lock);
                chowner(shr, old, new);