turbonss/src/buffer_manage.c
2006-04-19 18:02:40 +00:00

67 lines
2.4 KiB
C

#include "buffer_manage.h"
#include "buffer_entry.h"
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
struct __buffer_manage_t
{
cmph_uint32 memory_avail; // memory available
buffer_entry_t ** buffer_entries; // buffer entries to be managed
cmph_uint32 nentries; // number of entries to be managed
cmph_uint32 *memory_avail_list; // memory available list
int pos_avail_list; // current position in memory available list
};
buffer_manage_t * buffer_manage_new(cmph_uint32 memory_avail, cmph_uint32 nentries)
{
cmph_uint32 memory_avail_entry, i;
buffer_manage_t *buff_manage = (buffer_manage_t *)malloc(sizeof(buffer_manage_t));
assert(buff_manage);
buff_manage->memory_avail = memory_avail;
buff_manage->buffer_entries = (buffer_entry_t **)calloc(nentries, sizeof(buffer_entry_t *));
buff_manage->memory_avail_list = (cmph_uint32 *)calloc(nentries, sizeof(cmph_uint32));
buff_manage->pos_avail_list = -1;
buff_manage->nentries = nentries;
memory_avail_entry = buff_manage->memory_avail/buff_manage->nentries + 1;
for(i = 0; i < buff_manage->nentries; i++)
{
buff_manage->buffer_entries[i] = buffer_entry_new(memory_avail_entry);
}
return buff_manage;
}
void buffer_manage_open(buffer_manage_t * buffer_manage, cmph_uint32 index, char * filename)
{
buffer_entry_open(buffer_manage->buffer_entries[index], filename);
}
cmph_uint8 * buffer_manage_read_key(buffer_manage_t * buffer_manage, cmph_uint32 index)
{
cmph_uint8 * key = NULL;
if (buffer_manage->pos_avail_list >= 0 ) // recovering memory
{
cmph_uint32 new_capacity = buffer_entry_get_capacity(buffer_manage->buffer_entries[index]) + buffer_manage->memory_avail_list[(buffer_manage->pos_avail_list)--];
buffer_entry_set_capacity(buffer_manage->buffer_entries[index], new_capacity);
//fprintf(stderr, "recovering memory\n");
}
key = buffer_entry_read_key(buffer_manage->buffer_entries[index]);
if (key == NULL) // storing memory to be recovered
{
buffer_manage->memory_avail_list[++(buffer_manage->pos_avail_list)] = buffer_entry_get_capacity(buffer_manage->buffer_entries[index]);
//fprintf(stderr, "storing memory to be recovered\n");
}
return key;
}
void buffer_manage_destroy(buffer_manage_t * buffer_manage)
{
cmph_uint32 i;
for(i = 0; i < buffer_manage->nentries; i++)
{
buffer_entry_destroy(buffer_manage->buffer_entries[i]);
}
free(buffer_manage->memory_avail_list);
free(buffer_manage->buffer_entries);
free(buffer_manage);
}