static int cfs_flush(const char *path, struct fuse_file_info *info)
{
openfile *of = (openfile *)(uintptr_t)info->fh;
if (of)
{
update_dir_cache(path, cloudfs_file_size(of->fd), 0, 0);
if (of->flags & O_RDWR || of->flags & O_WRONLY)
{
FILE *fp = fdopen(dup(of->fd), "r");
rewind(fp);
if (!cloudfs_object_read_fp(path, fp))
{
fclose(fp);
return -ENOENT;
}
fclose(fp);
}
}
return 0;
}
//todo: flush will upload a file again even if just file attributes are changed.
//optimisation needed to detect if content is changed and to only save meta when just attribs are modified.
static int cfs_flush(const char* path, struct fuse_file_info* info)
{
debugf(DBG_LEVEL_NORM, KBLU "cfs_flush(%s)", path);
debug_print_descriptor(info);
openfile* of = (openfile*)(uintptr_t)info->fh;
int errsv = 0;
if (of)
{
// get the actual file size and truncate it. This ensures that if the new file is smaller
// than the previous one, the proper size is uploaded.
struct stat stbuf;
cfs_getattr(path, &stbuf);
update_dir_cache(path, stbuf.st_size, 0, 0);
ftruncate(of->fd, stbuf.st_size);
if (of->flags & O_RDWR || of->flags & O_WRONLY)
{
FILE* fp = fdopen(dup(of->fd), "r");
errsv = errno;
if (fp != NULL)
{
rewind(fp);
//calculate md5 hash, compare with cloud hash to determine if file content is changed
char md5_file_hash_str[MD5_DIGEST_HEXA_STRING_LEN] = "\0";
file_md5(fp, md5_file_hash_str);
dir_entry* de = check_path_info(path);
if (de && de->md5sum != NULL && (!strcasecmp(md5_file_hash_str, de->md5sum)))
{
//file content is identical, no need to upload entire file, just update metadata
debugf(DBG_LEVEL_NORM, KBLU
"cfs_flush(%s): skip full upload as content did not change", path);
cloudfs_update_meta(de);
}
else
{
rewind(fp);
debugf(DBG_LEVEL_NORM, KBLU
"cfs_flush(%s): perform full upload as content changed (or no file found in cache)",
path);
if (!cloudfs_object_read_fp(path, fp))
{
fclose(fp);
errsv = errno;
debugf(DBG_LEVEL_NORM, KRED"exit 0: cfs_flush(%s) result=%d:%s", path, errsv,
strerror(errno));
return -ENOENT;
}
}
fclose(fp);
errsv = errno;
}
else
debugf(DBG_LEVEL_EXT, KRED "status: cfs_flush, err=%d:%s", errsv,
strerror(errno));
}
}
debugf(DBG_LEVEL_NORM, KBLU "exit 1: cfs_flush(%s) result=%d:%s", path, errsv,
strerror(errno));
return 0;
}
