file-cache.h revision c25356d5978632df6203437e1953bcb29e0c736f
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen/* Create a new file cache. It works very much like file-backed mmap()ed
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen memory, but it works more nicely with remote filesystems (no SIGBUS). */
d5cebe7f98e63d4e2822863ef2faa4971e8b3a5dTimo Sirainen/* Destroy the cache and set cache pointer to NULL. */
d5cebe7f98e63d4e2822863ef2faa4971e8b3a5dTimo Sirainenvoid file_cache_free(struct file_cache **cache);
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen/* Change cached file descriptor. Invalidates the whole cache. */
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainenvoid file_cache_set_fd(struct file_cache *cache, int fd);
f7e0daedc6838c45df6b2a0724a57662b92e7df4Timo Sirainen/* Change the memory allocated for the cache. This can be used to immediately
f7e0daedc6838c45df6b2a0724a57662b92e7df4Timo Sirainen set the maximum size so there's no need to grow the memory area with
f7e0daedc6838c45df6b2a0724a57662b92e7df4Timo Sirainen possibly slow copying. */
f7e0daedc6838c45df6b2a0724a57662b92e7df4Timo Sirainenint file_cache_set_size(struct file_cache *cache, uoff_t size);
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen/* Read data from file, returns how many bytes was actually read or -1 if
137ea7ca34005345aa2304a940149b7f3774d727Timo Sirainen error occurred. */
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainenssize_t file_cache_read(struct file_cache *cache, uoff_t offset, size_t size);
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen/* Returns pointer to beginning of cached file. Only parts of the returned
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen memory that are valid are the ones that have been file_cache_read().
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen Note that the pointer may become invalid after calling file_cache_read(). */
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainenconst void *file_cache_get_map(struct file_cache *cache, size_t *size_r);
b22f3db16d33b8e509b7331e46108c313e7f3b94Timo Sirainen/* Update cached memory area. Mark fully written pages as cached. */
b22f3db16d33b8e509b7331e46108c313e7f3b94Timo Sirainenvoid file_cache_write(struct file_cache *cache, const void *data, size_t size,
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen/* Invalidate cached memory area. It will be read again next time it's tried
1098fc409a45e7603701dc94635927a673bee0c1Timo Sirainen to be accessed. */