int
fileTruncate(File *f, char *uid)
{
if(fileIsDir(f)){
vtSetError(ENotFile);
return 0;
}
if(!fileLock(f))
return 0;
if(f->source->mode != OReadWrite){
vtSetError(EReadOnly);
fileUnlock(f);
return 0;
}
if(!sourceLock(f->source, -1)){
fileUnlock(f);
return 0;
}
if(!sourceTruncate(f->source)){
sourceUnlock(f->source);
fileUnlock(f);
return 0;
}
sourceUnlock(f->source);
fileUnlock(f);
fileWAccess(f, uid);
return 1;
}
int
sourceSetSize(Source *r, uint64_t size)
{
int depth;
Entry e;
Block *b;
assert(sourceIsLocked(r));
if(size == 0)
return sourceTruncate(r);
if(size > VtMaxFileSize || size > ((uint64_t)MaxBlock)*r->dsize) {
vtSetError(ETooBig);
return 0;
}
b = sourceLoad(r, &e);
if(b == nil)
return 0;
/* quick out */
if(e.size == size) {
blockPut(b);
return 1;
}
depth = sizeToDepth(size, e.psize, e.dsize);
if(depth < e.depth) {
if(!sourceShrinkDepth(r, b, &e, depth)) {
blockPut(b);
return 0;
}
} else if(depth > e.depth) {
if(!sourceGrowDepth(r, b, &e, depth)) {
blockPut(b);
return 0;
}
}
if(size < e.size)
sourceShrinkSize(r, &e, size);
e.size = size;
entryPack(&e, b->data, r->offset % r->epb);
blockDirty(b);
blockPut(b);
return 1;
}
