terom@30: 
terom@30: #include "cache.h"
terom@30: #include "common.h"
terom@30: 
terom@30: struct cache_op {
terom@30:     u_int8_t key[CACHE_KEY];
terom@30: 
terom@30:     struct cache_nest *nest;
terom@30: 
terom@30:     u_int8_t obj_nest;
terom@30:     u_int32_t obj_offset;
terom@30:     u_int16_t obj_length:
terom@30: 
terom@30:     void *mmap_addr;
terom@30:     
terom@30:     // for linked lists
terom@30:     struct cache_op *next;
terom@30: };
terom@30: 
terom@30: int _cache_op_get (struct cache_op **op_info, struct cache *cache_info, u_int8_t key[CACHE_KEY_SIZE]) {
terom@30:     struct cache_op *op;
terom@30: 
terom@30:     // first, search the read queue
terom@30:     for (op = cache_info->rop_list; op; op = op->next) {
terom@30:         if (memcmp(op->key, key, CACHE_KEY_SIZE))
terom@30:             break;
terom@30:     }
terom@30: 
terom@30:     if (!op) {
terom@30:         // look for in-progress write ops
terom@30:         for (int i = 0; i < CACHE_NEST_COUNT; i++) {
terom@30:             op = ctx->nests[i].op;
terom@30: 
terom@30:             if (op && memcmp(op->key, key, CACHE_KEY_SIZE))
terom@30:                 break;
terom@30:     }
terom@30: 
terom@30:     if (!op) {
terom@30:         // look for queued write ops
terom@30:         for (op = cache_info->wop_list; op; op = op->next) {
terom@30:             if (memcmp(op->key, key, CACHE_KEY_SIZE))
terom@30:                 break;
terom@30:         }
terom@30:     }
terom@30: 
terom@30:     if (!op) {
terom@30:         // alloc a new op struct
terom@30:         op = calloc(1, sizeof(*op));
terom@30:         
terom@30:         // look it up in the index
terom@30:         if (_cache_index_find(cache_info->index, key, &op->nest, &op->obj_offset, &op->obj_length) == 0) {
terom@30:             // found it in some nest
terom@30:             
terom@30:             // XXX: enter read list and start read
terom@30: 
terom@30:         } else {
terom@30:             // not in the cache, try and find an unused nest to write it
terom@30:             if (_cache_nest_assign_op(cache_info, op, &op->nest) == 0) {
terom@30:                 // excellent, we can start writing directly
terom@30:                 
terom@30:                 // XXX: start writing
terom@30: 
terom@30:             } else {
terom@30:                 // enter the wait queue...
terom@30:                 
terom@30:                 // XXX: enter write queue
terom@30:             }
terom@30:         }
terom@30:     } else {
terom@30:         // XXX: start reading
terom@30:     }
terom@30: }
terom@30: