search for: gzip_can_ext

...= "gzip", - .longname = "nbdkit gzip filter", - .unload = gzip_unload, - .thread_model = gzip_thread_model, - .open = gzip_open, - .prepare = gzip_prepare, - .can_write = gzip_can_write, - .can_extents = gzip_can_extents, - .can_cache = gzip_can_cache, - .prepare = gzip_prepare, - .get_size = gzip_get_size, - .pread = gzip_pread, + .name = "gzip", + .longname = "nbdkit gzip filter", + .unload = gzip_unload, +...

...a); +} + +/* Whatever the plugin says, this filter makes it read-only. */ +static int +gzip_can_write (struct nbdkit_next_ops *next_ops, void *nxdata, + void *handle) +{ + return 0; +} + +/* Similar to above, whatever the plugin says, extents are not + * supported. + */ +static int +gzip_can_extents (struct nbdkit_next_ops *next_ops, void *nxdata, + void *handle) +{ + return 0; +} + +/* We are already operating as a cache regardless of the plugin's + * underlying .can_cache, but it's easiest to just rely on nbdkit's + * behavior of calling .pread for caching....

....longname = "nbdkit gzip filter", > - .unload = gzip_unload, > - .thread_model = gzip_thread_model, > - .open = gzip_open, > - .prepare = gzip_prepare, > - .can_write = gzip_can_write, > - .can_extents = gzip_can_extents, > - .can_cache = gzip_can_cache, > - .prepare = gzip_prepare, > - .get_size = gzip_get_size, > - .pread = gzip_pread, > + .name = "gzip", > + .longname = "nbdkit gzip filter", > + .un...

...assert (size == -1); > + > + /* Get the size of the underlying plugin. */ > + compressed_size = next_ops->get_size (nxdata); If we wanted, we could save this... > +/* Similar to above, whatever the plugin says, extents are not > + * supported. > + */ > +static int > +gzip_can_extents (struct nbdkit_next_ops *next_ops, void *nxdata, > + void *handle) Well, since we stored it as a temp file, we could actually report extents off of lseek(SEEK_HOLE). But that can be added separately, if we want it (it goes back to your notion of a library for file-based...

Applies on top of my pending series for the exportname filter, addressing one of the todo's in that cover letter. Eric Blake (2): filters: Add .export_description wrappers ext2: Supply .list_exports and .default_export filters/ext2/nbdkit-ext2-filter.pod | 3 +- tests/Makefile.am | 16 +++- filters/ext2/ext2.c | 125 +++++++++++++++++++---------

It's been several weeks since I posted v2 (I got distracted by improving libnbd to better test things, which in turn surfaced some major memory leak problems in nbdsh that are now fixed). Many of the patches are minor rebases from v2, with the biggest changes being fallout from: - patch 2: rename nbdkit_add_default_export to nbdkit_use_default_export - overall: this missed 1.22, so update