similar to: [PATCH nbdkit v2] New tmpdisk plugin.

This allows us to be much more flexible about what commands can be used. It also means we do not need to encode any special behaviour for type or label parameters. --- plugins/tmpdisk/nbdkit-tmpdisk-plugin.pod | 91 +++++++++----- plugins/tmpdisk/tmpdisk.c | 147 ++++++++++++++-------- plugins/tmpdisk/default-command.sh.in | 6 + 3 files changed, 164 insertions(+), 80

This allows us to be much more flexible about what commands can be used. It also means we do not need to encode any special behaviour for type or label parameters. XXX However one problem which is not addressed here: The $disk passed to the shell script fragment must be updated, not replaced. This is because currently the plugin has a file descriptor opened on this file. If it is deleted by

This allows us to be much more flexible about what commands can be used. It also means we do not need to encode any special behaviour for type or label parameters. --- plugins/tmpdisk/nbdkit-tmpdisk-plugin.pod | 115 ++++++++++---- tests/Makefile.am | 2 + plugins/tmpdisk/tmpdisk.c | 184 ++++++++++++++++------ plugins/tmpdisk/default-command.sh.in |

On 3/17/20 3:53 AM, Richard W.M. Jones wrote: > This can be used for creating temporary disks to thin clients, as a > kind of "remote tmpfs". > > See also: > https://www.redhat.com/archives/libguestfs/2020-March/msg00134.html > --- > +++ b/plugins/tmpdisk/nbdkit-tmpdisk-plugin.pod > @@ -0,0 +1,157 @@ > +=head1 NAME > + > +nbdkit-tmpdisk-plugin - create

This creates filesystems on demand. A client simply connects with a desired export name and a new export is created. The export is persistent (until deleted by the server admin), and clients may disconnect and reconnect. In some respects this is similar to the nbdkit-tmpdisk-plugin, or nbdkit-file-plugin with the dir= option. --- plugins/ondemand/nbdkit-ondemand-plugin.pod | 190 ++++++

v2 was here: https://www.redhat.com/archives/libguestfs/2020-March/msg00154.html v3: - Micro-optimize tmpdir. - Quote $disk in default command shell fragment. - Don't redirect mkfs output to /dev/null. Instead use exec </dev/null >/dev/null before the shell fragment. We may want to do this in other places where we run external shell scripts, or more generally for all

An evolution of v1 here: https://www.redhat.com/archives/libguestfs/2020-April/msg00035.html I want to generalize the tmpdisk plugin, particularly so you can use commands like ‘qemu-img create’ or even ‘virt-builder’. (Actually virt-builder really works - I tested it - but of course it causes a 30+ second delay when connecting to the server.) You can now use commands such as: nbdkit tmpdisk

Unfinished (needs tests). This is my attempt to make a "remote tmpfs" plugin as outlined in this prior email: https://www.redhat.com/archives/libguestfs/2020-March/msg00134.html Although it would be possible to construct something a bit like this using existing plugins and filters (perhaps with some new features in those filters) I think it may be nicer to have a dedicated plugin for

Patch 1/2 is uncontroversial. Patch 2/2 is an interesting idea I had to generalize this plugin. It already uses a complete embedded shell script to do most of the work. What if, instead of making special cases for "type" and "label" params, we simply turn any other plugin parameters into script variables? This part of it works fine. However there is another problem which is

v2 was here: https://www.redhat.com/archives/libguestfs/2020-April/msg00075.html In v3: - Add [VAR=VALUE ...] to manual. - Various minor improvements to the manual. - Work (at least, in theory - not tested) with block devices or symlinks. I didn't document this because it's hard to ensure these files or block devices would be cleaned up, so here be dragons. - Remove O_NOCTTY. -

From: "Richard W.M. Jones" <rjones@redhat.com> This plugin allows you to create a complete ext2, ext3 or ext4 filesystem in a GPT partitioned disk image. This can be attached as a disk to a Linux virtual machine. It is implemented using e2fsprogs mke2fs ‘-d’ option thus allowing the implementation to be very small and simple, with all the hard work done by mke2fs. Although

From: "Richard W.M. Jones" <rjones@redhat.com> This plugin allows you to create a complete ext2 filesystem in a GPT partitioned disk image. This can be attached as a disk to a Linux virtual machine. It is implemented using libext2fs (the same as supermin). Although there is some overlap with nbdkit-iso-plugin and nbdkit-floppy-plugin, the implementations and use cases of all

On 2/19/19 1:49 AM, Richard W.M. Jones wrote: > From: "Richard W.M. Jones" <rjones@redhat.com> > > This plugin allows you to create a complete ext2 filesystem in a GPT > partitioned disk image. This can be attached as a disk to a Linux > virtual machine. It is implemented using libext2fs (the same as > supermin). > > Although there is some overlap with

--- configure.ac | 5 + filters/Makefile.am | 4 + filters/cow/Makefile.am | 65 +++++++ filters/cow/cow.c | 392 ++++++++++++++++++++++++++++++++++++++ filters/cow/nbdkit-cow-filter.pod | 162 ++++++++++++++++ tests/Makefile.am | 6 + tests/test-cow.sh | 98 ++++++++++ 7 files changed, 732

This filter can be used to open tar files. It uses the technique first suggested by Eric Blake here: https://www.redhat.com/archives/libguestfs/2020-July/msg00017.html We suggest that nbdkit-tar-plugin is deprecated in nbdkit 1.26, but it might happen later. --- docs/nbdkit-captive.pod | 4 +- filters/offset/nbdkit-offset-filter.pod | 2 +- filters/tar/nbdkit-tar-filter.pod

Turn the existing nbdkit-gzip-plugin into a filter so it can be applied on top of files or other sources: nbdkit file --filter=gzip file.gz nbdkit curl --filter=gzip https://example.com/disk.gz Because of the nature of the gzip format which is not blocked based and thus not seekable, this filter caches the whole uncompressed file in a hidden temporary file. This is required in order to

--- plugins/tar/{tar.pl => nbdkit-tar-plugin.pod} | 145 ++------- configure.ac | 2 - plugins/tar/Makefile.am | 41 +-- tests/Makefile.am | 14 +- plugins/tar/tar.c | 286 ++++++++++++++++++ tests/test-dump-plugin.sh | 2 +- tests/test-help-plugin.sh

Neutral refactoring. Makes the code a bit easier to handle and simplifies future commits. --- plugins/tmpdisk/Makefile.am | 17 ++++++++- plugins/tmpdisk/tmpdisk.c | 22 +++--------- plugins/tmpdisk/default-command.sh.in | 51 +++++++++++++++++++++++++++ .gitignore | 1 + 4 files changed, 72 insertions(+), 19 deletions(-) diff --git

This rather complex feature solves a problem for certain web services that require a cookie or token for access, especially one which must be periodically renewed. For motivation for this feature see the included documentation, and item (1)(b) here: https://www.redhat.com/archives/libguestfs/2020-July/msg00069.html --- plugins/curl/nbdkit-curl-plugin.pod | 142 ++++++++++++

Add a new filter to make it easier to add exports to a plugin that does advertise them, to avoid advertising where a plugin's list might be an information leak, and to alter which export name is used in place of "". I would love to be able to have a strict mode enforcing that .open is called only with an export name that the plugin was willing to advertise, but for that, we'll