/* public interfaces for block io routines */ #ifndef _BLOCK_H #define _BLOCK_H /*#define IBEX_STATS*/ /* define to get/dump block access stats */ #include <glib.h> /* version of file format */ #define IBEX_VERSION "ibx6" typedef guint32 nameid_t; typedef guint32 blockid_t; #define BLOCK_BITS (8) #define BLOCK_SIZE (1<<BLOCK_BITS) #define CACHE_SIZE 256 /* blocks in disk cache */ /* root block */ struct _root { char version[4]; blockid_t free; /* list of free blocks */ blockid_t roof; /* top of allocated space, everything below is in a free or used list */ blockid_t tail; /* list of 'tail' blocks */ blockid_t words; /* root of words index */ blockid_t names; /* root of names index */ char flags; /* state flags */ /* makes structure fill up to 1024 bytes */ char dummy[1024 - (sizeof(char)*5) - (sizeof(blockid_t)*5)]; }; #define IBEX_ROOT_SYNCF (1<<0) /* file is synced */ /* basic disk structure for (data) blocks */ struct _block { unsigned int next:32-BLOCK_BITS; /* next block */ unsigned int used:BLOCK_BITS; /* number of elements used */ nameid_t bl_data[(BLOCK_SIZE-4)/4]; /* references */ }; /* custom list structure, for a simple/efficient cache */ struct _listnode { struct _listnode *next; struct _listnode *prev; }; struct _list { struct _listnode *head; struct _listnode *tail; struct _listnode *tailpred; }; void ibex_list_new(struct _list *v); struct _listnode *ibex_list_addhead(struct _list *l, struct _listnode *n); struct _listnode *ibex_list_addtail(struct _list *l, struct _listnode *n); struct _listnode *ibex_list_remove(struct _listnode *n); /* in-memory structure for block cache */ struct _memblock { struct _memblock *next; struct _memblock *prev; blockid_t block; int flags; struct _block data; }; #define BLOCK_DIRTY (1<<0) struct _memcache { struct _list nodes; int count; /* nodes in cache */ GHashTable *index; /* blockid->memblock mapping */ int fd; /* file fd */ #ifdef IBEX_STATS GHashTable *stats; #endif struct _root root; /* root block */ /* temporary here */ struct _IBEXWord *words; /* word index */ }; #ifdef IBEX_STATS struct _stat_info { int read; int write; int cache_hit; int cache_miss; }; #endif /* IBEX_STATS */ struct _memcache *ibex_block_cache_open(const char *name, int flags, int mode); void ibex_block_cache_close(struct _memcache *block_cache); void ibex_block_cache_sync(struct _memcache *block_cache); void ibex_block_cache_flush(struct _memcache *block_cache); blockid_t ibex_block_get(struct _memcache *block_cache); void ibex_block_free(struct _memcache *block_cache, blockid_t blockid); void ibex_block_dirty(struct _block *block); struct _block *ibex_block_read(struct _memcache *block_cache, blockid_t blockid); #define block_number(x) ((x)>>BLOCK_BITS) #define block_location(x) ((x)<<BLOCK_BITS) #endif /* ! _BLOCK_H */