Commit graph

2895 commits

Author SHA1 Message Date
Eelco Dolstra bccff827dc Fix deadlock in IFD through the daemon
Fixes #4235.
2020-11-17 13:50:36 +01:00
regnat 7de21f6664 Make the sql debug statements more useful
Print the expanded sql query (with the variables bound to their value) rather
than the original one in case of error
2020-11-17 10:05:45 +01:00
Jake Waksbaum 01db455733 Fix deadlock in nix-store when max-connections=1
This fixes a bug I encountered where `nix-store -qR` will deadlock when
the `--include-outputs` flag is passed and `max-connections=1`.

The deadlock occurs because `RemoteStore::queryDerivationOutputs` takes
the only connection from the connection pool and uses it to check the
daemon version. If the version is new enough, it calls
`Store::queryDerivationOutputs`, which eventually calls
`RemoteStore::queryPartialDerivationOutputMap`, where we take another
connection from the connection pool to check the version again. Because
we still haven't released the connection from the caller, this waits for
a connection to be available, causing a deadlock.

This diff solves the issue by using `getProtocol` to check the protocol
version in the caller `RemoteStore::queryDerivationOutputs`, which
immediately frees the connection back to the pool before returning the
protocol version. That way we've already freed the connection by the
time we call `RemoteStore::queryPartialDerivationOutputMap`.
2020-11-16 02:35:50 -05:00
Maximilian Bosch 3a63fc6cd5
Allow substituting paths when building remotely using ssh-ng://
Until now, it was not possible to substitute missing paths from e.g.
`https://cache.nixos.org` on a remote server when building on it using
the new `ssh-ng` protocol.

This is because every store implementation except legacy `ssh://`
ignores the substitution flag passed to `Store::queryValidPaths` while
the `legacy-ssh-store` substitutes the remote store using
`cmdQueryValidPaths` when the remote store is opened with `nix-store
--serve`.

This patch slightly modifies the daemon protocol to allow passing an
integer value suggesting whether to substitute missing paths during
`wopQueryValidPaths`. To implement this on the daemon-side, the
substitution logic from `nix-store --serve` has been moved into a
protected method named `Store::substitutePaths` which gets currently
called from `LocalStore::queryValidPaths` and `Store::queryValidPaths`
if `maybeSubstitute` is `true`.

Fixes #2770
2020-11-05 20:12:37 +01:00
Eelco Dolstra e8c379555f LocalStore: Get rid of recursive_mutex 2020-11-03 14:45:24 +01:00
Eelco Dolstra 797a52e31d Add FIXME 2020-11-03 14:45:24 +01:00
Eelco Dolstra 7cf874c17d Don't use readDerivation() in addValidPath()
readDerivation() requires a valid path.

Fixes #4210.
2020-11-02 18:46:44 +01:00
Eelco Dolstra ab2ef851b6
Merge pull request #4207 from hercules-ci/fix-RemoteStore-filterSource-deadlock
Fix RemoteStore pool deadlock in filterSource etc
2020-11-02 14:46:10 +01:00
Eelco Dolstra db5424bf09 Don't send eval-related settings to the daemon 2020-11-02 13:57:58 +01:00
Robert Hensing e8a45d07bc Restore RestrictedStore.addToStoreFromDump implementation
It was accidentally removed in commit ca30abb3fb
2020-10-31 23:56:03 +01:00
Robert Hensing 2192cac634 Fix RemoteStore pool deadlock in filterSource etc 2020-10-30 21:47:34 +01:00
Eelco Dolstra ff4dea63c9 Generalize extra-* settings
This removes the extra-substituters and extra-sandbox-paths settings
and instead makes every array setting extensible by setting
"extra-<name> = <value>" in the configuration file or passing
"--<name> <value>" on the command line.
2020-10-29 18:17:39 +01:00
stev 869c0321ff Alter "wanted:" to "specified:" in hash mismatch output
This makes it even clearer which of the two hashes was specified in the
nix files. Some may think that "wanted" and "got" is obvious, but:
"got" could mean "got in nix file" and "wanted" could mean "want to see in nix file".
2020-10-29 00:33:14 +01:00
Eelco Dolstra 02a1facbdc
Merge pull request #4056 from tweag/non-ca-depending-on-ca
Allow non-CA derivations to depend on CA ones
2020-10-27 17:38:29 +01:00
regnat bc081bcd81 Inline unkownHashes
See https://github.com/NixOS/nix/pull/4056#discussion_r493661632
2020-10-27 07:29:25 +01:00
regnat c092fa4702 Allow non-CA derivations to depend on CA derivations 2020-10-27 07:29:23 +01:00
Christian Kampka 461cf2b856
Add NIX_CONFIG env var for applying nix.conf overrides 2020-10-21 13:41:26 +02:00
Eelco Dolstra fda835b231
Merge pull request #4143 from obsidiansystems/typed-goal-maps
Properly type the derivation and substitution goal maps
2020-10-18 18:12:21 +02:00
Robert Hensing bd9eb5c743 DerivationGoal: only retry if output closure incomplete is only problem 2020-10-18 14:26:37 +02:00
Robert Hensing 94f1e4a441 Typo 2020-10-18 14:26:37 +02:00
John Ericson 7ed46c1574 Explain that upcast_goal is still a static cast 2020-10-17 21:50:12 +00:00
John Ericson 57d0432b39 Just use auto in two places. 2020-10-17 21:47:52 +00:00
John Ericson e6f8ae56d8 tab -> space 2020-10-17 21:45:31 +00:00
John Ericson 0fefc2a439 Merge remote-tracking branch 'upstream/master' into typed-goal-maps 2020-10-14 20:49:01 +00:00
Eelco Dolstra 11882d7c7c Create /etc/passwd *after* figuring out the sandbox uid/gid
Fixes build failures like

  # nix log /nix/store/gjaa0psfcmqvw7ivggsncx9w364p3s8s-sshd.conf-validated.drv
  No user exists for uid 30012
2020-10-14 12:20:58 +02:00
John Ericson 55592b253f Add some more docs 2020-10-13 18:04:24 +00:00
John Ericson 13804f126e Merge remote-tracking branch 'upstream/master' into typed-goal-maps 2020-10-13 18:02:32 +00:00
Eelco Dolstra 2653801939 Merge branch 'split_build_cc' of https://github.com/obsidiansystems/nix 2020-10-13 15:36:55 +02:00
John Ericson 1b8ebe92dc Merge remote-tracking branch 'obsidian/split_build_cc' into typed-goal-maps 2020-10-12 20:47:22 +00:00
John Ericson a73959e6be Merge remote-tracking branch 'upstream/master' into split_build_cc 2020-10-12 17:20:46 +00:00
John Ericson d334fd4882 Merge branches 'split_build_hh-0', 'split_build_hh-1', 'split_build_hh-2', 'split_build_hh-3' and 'split_build_hh-4' into split_build_cc 2020-10-12 17:20:12 +00:00
John Ericson 542972f029 Trim worker.hh 2020-10-12 17:16:48 +00:00
John Ericson 0e2306204a Rename to hand-hold git (worker.hh) 2020-10-12 17:16:48 +00:00
John Ericson 3ffa3546bd Trim substitution-goal.hh 2020-10-12 17:16:25 +00:00
John Ericson e77a2344d5 Rename to hand-hold git (substitution-goal.hh) 2020-10-12 17:16:25 +00:00
John Ericson d585b4c54f Trim hook-instance.hh 2020-10-12 17:16:13 +00:00
John Ericson 10b749a156 Rename to hand-hold git (hook-instance.hh) 2020-10-12 17:16:13 +00:00
John Ericson 8067d32f2a Trim goal.hh 2020-10-12 17:16:00 +00:00
John Ericson 0d0e345cdc Rename to hand-hold git (goal.hh) 2020-10-12 17:16:00 +00:00
John Ericson 2ce726947a Trim derivation-goal.hh 2020-10-12 17:15:32 +00:00
John Ericson 4eb8c69853 Rename to hand-hold git (derivation-goal.hh) 2020-10-12 17:15:32 +00:00
John Ericson f7099965bf Change .cc files to use split build headers 2020-10-12 17:08:52 +00:00
John Ericson 5a97621d6d Prepare for build/*.hh headers 2020-10-12 17:07:51 +00:00
volth eee18f88dd
Handle amount of disk space saved by hard linking being negative
Fixes bogus messages like "currently hard linking saves 17592186044416.00 MiB".
2020-10-12 16:06:38 +00:00
John Ericson 15fdb7cc6b Split out uds-remote-store.{cc.hh} 2020-10-11 17:37:05 +00:00
John Ericson 38e3897162 Copy {uds-,}remote-store.{cc,hh}
This prepares for the splitting that happens in the next commit.
2020-10-11 17:18:26 +00:00
John Ericson 5c74a6147b Properly type the derivation and substitution goal maps
As a bonus, Worker::removeGoal is less inefficient.
2020-10-11 17:07:14 +00:00
John Ericson 8cc510fb79 Merge branches 'build-1', 'build-2', 'build-3', 'build-4', 'build-5', 'build-6', 'build-7' and 'build-8' into split_build_cc 2020-10-11 16:44:34 +00:00
John Ericson bcb67e1ed8 Trim lock.cc 2020-10-11 16:44:19 +00:00
John Ericson e0be04129b Rename to hand-hold git (lock.cc) 2020-10-11 16:44:14 +00:00
John Ericson dbc588651c Trim lock.hh 2020-10-11 16:44:07 +00:00
John Ericson d0004bfcab Rename to hand-hold git (lock.hh) 2020-10-11 16:43:59 +00:00
John Ericson eed53ed87a Trim build/worker.cc 2020-10-11 16:43:51 +00:00
John Ericson 904e315dae Rename to hand-hold git (build/worker.cc) 2020-10-11 16:43:42 +00:00
John Ericson d24ffe0eb1 Trim build/substitution-goal.cc 2020-10-11 16:43:24 +00:00
John Ericson 3633b3572b Rename to hand-hold git (build/substitution-goal.cc) 2020-10-11 16:43:18 +00:00
John Ericson 4bdff7d1b0 Trim build/local-store-build.cc 2020-10-11 16:43:12 +00:00
John Ericson dc5225cde5 Rename to hand-hold git (build/local-store-build.cc) 2020-10-11 16:43:05 +00:00
John Ericson 159054f730 Trim build/hook-instance.cc 2020-10-11 16:42:35 +00:00
John Ericson f0b8987299 Rename to hand-hold git (build/hook-instance.cc) 2020-10-11 16:42:08 +00:00
John Ericson 819fe848ac Trim build/goal.cc 2020-10-11 16:41:58 +00:00
John Ericson 184bfc301e Rename to hand-hold git (build/goal.cc) 2020-10-11 16:41:18 +00:00
John Ericson 3bab1c5bb0 Trim build/derivation-goal.cc 2020-10-11 16:41:11 +00:00
John Ericson 9629290eda Rename to hand-hold git (build/derivation-goal.cc) 2020-10-11 16:40:52 +00:00
John Ericson a4f0fecb03 Trim build.hh 2020-10-11 16:40:34 +00:00
John Ericson fc72cb0760 Rename to hand-hold git (build.hh) 2020-10-11 16:40:14 +00:00
John Ericson 428536fd75 Prepare for build/* files 2020-10-11 16:39:08 +00:00
John Ericson aef44cbaa9 Split out commonChildInit 2020-10-11 16:38:46 +00:00
John Ericson 6cc1541782 Split out local-fs-store.hh
This matches the already-existing `local-fs-store.cc`.
2020-10-09 20:18:08 +00:00
Eelco Dolstra 636ec17139
Remove stray DerivationOutputsAndPaths type 2020-10-09 15:41:24 +02:00
Eelco Dolstra 97ffc1e013 Dynamically disable user namespaces if CLONE_NEWUSER fails
This makes builds work inside nixos-enter.

Fixes #3145.
2020-10-07 22:46:01 +02:00
Eelco Dolstra 6aa64627c8 Support user namespaces being disabled
If max_user_namespaces is set to 0, then don't run the build in a user
namespace.

Fixes #4092.
2020-10-07 22:02:36 +02:00
Eelco Dolstra f66bbd8c7b Doh 2020-10-07 21:25:06 +02:00
Eelco Dolstra e705c24294 Tweak error messages 2020-10-07 17:28:43 +02:00
Eelco Dolstra c43e882f54 Serialize exceptions from the daemon to the client 2020-10-07 17:13:54 +02:00
Eelco Dolstra be149acfda Serialize exceptions from the sandbox process to the parent
Fixes #4118.
2020-10-07 16:34:03 +02:00
John Ericson 57d960dcd1 Remove generic std::optional<T> suppport from worker proto
See comment for rational; I think it's good to leave a comment lest
anyone is tempted to add such a sum-type instance again.

Fixes #4113
2020-10-07 12:50:37 +00:00
Eelco Dolstra d761485010 Prevent a deadlock when user namespace setup fails
Observed on Centos 7 when user namespaces are disabled:
DerivationGoal::startBuilder() throws an exception, ~DerivationGoal()
waits for the child process to exit, but the child process hangs
forever in drainFD(userNamespaceSync.readSide.get()) in
DerivationGoal::runChild(). Not sure why the SIGKILL doesn't get
through.

Issue #4092.
2020-10-06 18:57:23 +02:00
Eelco Dolstra ad143c5b3b Shut up some clang warnings 2020-10-06 14:52:30 +02:00
Eelco Dolstra 85c8be6286 Remove static variable name clashes
This was useful for an experiment with building Nix as a single
compilation unit. It's not very useful otherwise but also doesn't
hurt...
2020-10-06 13:49:20 +02:00
Eelco Dolstra 6691256e79 Factor out common showBytes() 2020-10-06 10:40:49 +02:00
Eelco Dolstra d0bb544128 Add missing #pragma once 2020-10-06 10:40:07 +02:00
Eelco Dolstra 88a667e49e
Fix s3:// store
Fixes https://github.com/NixOS/nixos-org-configurations/issues/123.
2020-10-05 17:53:30 +02:00
Eelco Dolstra 51c299213b
Merge pull request #3935 from obsidiansystems/binary-cache-addToStoreFromDump
Get rid of Hash::dummy from BinaryCacheStore
2020-10-05 14:41:28 +02:00
Eelco Dolstra f3aba88737
Merge pull request #3895 from obsidiansystems/templated-daemon-protocol
More templated STL support for the daemon protocol
2020-10-05 14:40:27 +02:00
Eelco Dolstra 20a1e20d91 Style 2020-09-30 13:35:56 +02:00
John Ericson 69afaeace3 Merge remote-tracking branch 'upstream/master' into templated-daemon-protocol 2020-09-30 00:42:28 +00:00
John Ericson b759701652 nix::worker_proto -> worker_proto 2020-09-30 00:41:18 +00:00
John Ericson 45a0ed82f0 Revert "Use template structs instead of phantoms"
This reverts commit 9ab07e99f5.
2020-09-30 00:39:06 +00:00
Kevin Quick 5e7838512e
Remove github-access-token in favor of access-token. 2020-09-29 16:26:34 -07:00
Kevin Quick 66c3959e8c
Merge branch 'master' into access-tokens 2020-09-29 08:32:06 -07:00
Eelco Dolstra 5999978a05 Make Headers an optional argument 2020-09-29 13:05:19 +02:00
Eelco Dolstra cebd2fc35d Merge branch 'github-api-token' of https://github.com/imalsogreg/nix 2020-09-29 12:17:00 +02:00
John Ericson 00135e13f4 Clarify comment a bit 2020-09-28 18:19:10 +00:00
John Ericson 80e335bb58 Use drvPath2 and give it a better name 2020-09-28 15:43:56 +00:00
John Ericson 10202bbf29 Merge remote-tracking branch 'upstream/master' into ca-floating-upstream 2020-09-28 15:39:11 +00:00
John Ericson 6c31297d80
Update src/libstore/binary-cache-store.cc
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
2020-09-28 11:32:58 -04:00
Eelco Dolstra 649c465873
Merge pull request #4064 from serokell/balsoft/fix-max-jobs
Fix max-jobs option
2020-09-28 10:42:02 +02:00
John Ericson 25fffdda86
Remove redundant nar hash and size setting
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2020-09-26 10:17:30 -04:00
John Ericson 1832436526 Fix up BinaryCacheStore::addToStore taking a path 2020-09-26 04:56:29 +00:00
John Ericson 5db83dd771 BinaryCacheStore::addTextToStore include CA field 2020-09-26 03:21:36 +00:00
John Ericson c40c832f19 Merge remote-tracking branch 'obsidian/master' into binary-cache-addToStoreFromDump 2020-09-26 00:21:45 +00:00
Gregory Hale faa5607f54 Merge remote-tracking branch 'origin/master' into github-api-token 2020-09-25 12:10:58 -04:00
Eelco Dolstra 7d81582488
Merge pull request #3953 from obsidiansystems/basic-derivation-goal-outputs
Deduplicate basic derivation goals too
2020-09-25 17:21:19 +02:00
Kevin Quick 5a35cc29bf
Re-add support for github-access-token, but mark as deprecated. 2020-09-25 08:09:56 -07:00
Kevin Quick ef2a14be19
Fix reference to older name for access-tokens config value. 2020-09-25 08:08:27 -07:00
Kevin Quick 8fba2a8b54
Update to use access-tokens configuration for github/gitlab access.
This change provides support for using access tokens with other
instances of GitHub and GitLab beyond just github.com and
gitlab.com (especially company-specific or foundation-specific
instances).

This change also provides the ability to specify the type of access
token being used, where different types may have different handling,
based on the forge type.
2020-09-24 22:49:44 -07:00
Alexander Bantyev ed218e1d6c
Fix max-jobs option
After 0ed946aa61, max-jobs setting (-j/--max-jobs)
stopped working.

The reason was that nrLocalBuilds (which compared to maxBuildJobs to figure
out whether the limit is reached or not) is not incremented yet when tryBuild
is started; So, the solution is to move the check to tryLocalBuild.

Closes https://github.com/nixos/nix/issues/3763
2020-09-25 00:07:42 +03:00
Eelco Dolstra 4ce8a3ed45 Hopefully fix EPERM on macOS 2020-09-23 21:29:10 +02:00
Eelco Dolstra 9a24ece122 Fix exception 2020-09-23 20:21:08 +02:00
Eelco Dolstra 236d9ee7f7 lstat() cleanup 2020-09-23 19:17:28 +02:00
Eelco Dolstra 688bd4fb50 After rewriting a path, make it read-only 2020-09-23 19:10:16 +02:00
Eelco Dolstra cec9473871 DerivationGoal::registerOutputs(): Don't canonicalize twice
Fixes #4021.
2020-09-23 18:21:22 +02:00
Eelco Dolstra d4f8163d10 canonicalisePathMetaData_(): Change assertion to error message 2020-09-23 18:21:22 +02:00
Eelco Dolstra e8f0b1e996 DerivationGoal::registerOutputs(): Fix bad format string 2020-09-23 18:21:22 +02:00
John Ericson 3f226f71c1 Return more info from BinaryCacheStore::addToStoreCommon
We don't need it yet, but we could/should in the future, and it's a
cost-free change since we already have the reference. I like it.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2020-09-23 14:40:41 +00:00
John Ericson 412b3a54fb
Clarify FIXME in BinaryCacheStore::addToStoreCommon
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
2020-09-23 10:36:55 -04:00
John Ericson 9fbc31a65b Get rid of Hash::dummy from BinaryCacheStore 2020-09-23 04:56:04 +00:00
John Ericson 993229cdaf Deduplicate basic derivation goals too
See comments for security concerns.

Also optimize goal creation by not traversing map twice.
2020-09-22 17:13:59 +00:00
John Ericson e9fc2031f0 Merge remote-tracking branch 'upstream/master' into templated-daemon-protocol 2020-09-22 14:18:31 +00:00
regnat 67cc356bb3 Merge remote-tracking branch 'origin/master' into non-ca-depending-on-ca 2020-09-22 16:11:25 +02:00
Eelco Dolstra 980edd1f3a RemoteStore::addCAToStore(): Don't hold connection while calling queryPathInfo()
This leads to a deadlock if we're at the connection limit.
2020-09-22 15:28:20 +02:00
Eelco Dolstra 5b107f2c5f
Merge pull request #4038 from maljub01/master
Add a nix.conf option for allowing a symlinked store
2020-09-22 13:19:22 +02:00
Eelco Dolstra 35a0ac1838 Style fixes 2020-09-22 11:40:19 +02:00
Eelco Dolstra 92ac8df0ec Merge branch 'add-ca-to-store' of https://github.com/hercules-ci/nix 2020-09-22 11:31:33 +02:00
John Ericson 3786a801c3 Merge remote-tracking branch 'upstream/master' into ca-floating-upstream 2020-09-22 04:15:55 +00:00
John Ericson b92d3b2edd Merge remote-tracking branch 'upstream/master' into templated-daemon-protocol 2020-09-22 00:45:55 +00:00
Cole Helbling ba37299a03
Serialize SandboxMode enum to string for JSON
Rather than showing an integer as the default, instead show the boolean
referenced in the description.

The nix.conf.5 manpage used to show "default: 0", which is unnecessarily
opaque and confusing (doesn't 0 mean false, even though the default is
true?); now it properly shows that the default is true.
2020-09-21 10:36:45 -07:00
Eelco Dolstra 0716adaa8b abstractsettingtojson.hh -> abstract-setting-to-json.hh 2020-09-21 18:49:43 +02:00
Eelco Dolstra 340ca382c4 Don't include nlohmann/json.hpp in globals.hh
This reduces compilation time by 207s.

Issue #4045.
2020-09-21 18:47:18 +02:00
Eelco Dolstra d51ba43047 Move Callback into its own header
This gets rid of the inclusion of <future> in util.hh, cutting
compilation time by ~20s (CPU time).

Issue #4045.
2020-09-21 18:42:21 +02:00
Marwan Aljubeh f80ffeb8c9 Update the variable name accordingly 2020-09-21 17:29:08 +01:00
Eelco Dolstra e8e1d420f3 Don't include <regex> in header files
This reduces compilation time by ~15 seconds (CPU time).

Issue #4045.
2020-09-21 18:22:45 +02:00
Marwan Aljubeh 4e1a04733d Use a better name for the config option 2020-09-21 16:32:22 +01:00
Robert Hensing ca30abb3fb Document addCAToStore/addToStoreFromDump source drainage
Also checked that all usages satisfy the requirement and
removed dead code.
2020-09-21 07:55:47 +02:00
Robert Hensing fa08db5c4c wopAddToStore: return ValidPathInfo
A ValidPathInfo is created anyway. By returning it we can save a
roundtrip and we have a nicer interface.
2020-09-21 07:55:47 +02:00
Robert Hensing 7c68264085 wopAddToStore: add RepairFlag 2020-09-21 07:55:47 +02:00
Robert Hensing fbf509c113 parseContentAddressMethodPrefix: use string_view
Co-authored-by: John Ericson <git@JohnEricson.me>
2020-09-21 07:55:47 +02:00
Robert Hensing 8279178b07 Move FramedSink next to FramedSource 2020-09-21 07:55:47 +02:00
Robert Hensing ecc8088cb7 wopAddToStore: Throw to clarify unused refs
Co-authored-by: John Ericson <git@JohnEricson.me>
2020-09-21 07:55:47 +02:00
Robert Hensing c602ebfb34 Refactor wopAddToStore to make wopAddTextToStore obsolete 2020-09-21 07:55:45 +02:00
Robert Hensing e34fe47d0c Overhaul wopAddToStore 2020-09-21 07:54:05 +02:00
Marwan Aljubeh e40772cd35 Lint issue: replacing tabs with spaces 2020-09-18 17:18:45 +01:00
Marwan Aljubeh c00e078343 Add a nix.conf option for allowing a symlinked store 2020-09-18 17:10:39 +01:00
Robert Hensing 14b30b3f3d Move FramedSource and FramedSink, extract withFramedSink 2020-09-17 20:21:04 +02:00
Robert Hensing dfa547c6a8 Add ContentAddressMethod and parse/render it 2020-09-17 20:21:04 +02:00
Robert Hensing 9ee3122ec7 Remove redundant import 2020-09-17 20:21:04 +02:00
John Ericson b7df353f27 Merge remote-tracking branch 'upstream/master' into ca-floating-upstream 2020-09-17 16:33:10 +00:00
Eelco Dolstra 649d3aaf24
Merge pull request #3829 from obsidiansystems/remove-storetype-delegate-regStore
Remove storetype delegate reg store -- contains #3736
2020-09-17 13:55:01 +02:00
Eelco Dolstra b94a35ef40
Merge pull request #4027 from tweag/fix-gc-of-ca-derivations
Fix garbage collection of CA derivations
2020-09-17 13:46:26 +02:00