130     : fHead(head), fAvailable(available), fTail(tail)  in SkROBuffer()
133         fHead->ref();  in SkROBuffer()
143     if (fHead) {  in ~SkROBuffer()
144         fHead->unref();  in ~SkROBuffer()
158     if (buffer && buffer->fHead) {  in reset()
159         fBlock = &buffer->fHead->fBlock;  in reset()
194 SkRWBuffer::SkRWBuffer(size_t initialCapacity) : fHead(nullptr), fTail(nullptr), fTotalUsed(0) {  in SkRWBuffer()
196         fHead = SkBufferHead::Alloc(initialCapacity);  in SkRWBuffer()
197         fTail = &fHead->fBlock;  in SkRWBuffer()
203     if (fHead) {  in ~SkRWBuffer()
204         fHead->unref();  in ~SkRWBuffer()
220     if (nullptr == fHead) {  in append()
221         fHead = SkBufferHead::Alloc(length + reserve);  in append()
222         fTail = &fHead->fBlock;  in append()
242     if (fHead) {  in validate()
243         fHead->validate(fTotalUsed, fTail);  in validate()