Fixes <http://bugs.gnu.org/18049>.
Reported by Marek Benc <merkur32@gmail.com>.
* guix/scripts/system.scm (copy-closure): Pass #:state-directory to
'register-path'.
* guix/scripts/system.scm (references*, topologically-sorted*,
show-what-to-build*): New procedures.
(copy-closure): Turn into a monadic procedure.
(install): Likewise, and adjust parameter list.
(switch-to-system): Likewise.
(system-derivation-for-action, grub.cfg, maybe-build, perform-action):
New procedures.
(guix-system): Use them.
Fixes <http://bugs.gnu.org/17946>.
Notoriously, cron jobs may set LOGNAME only and not USER. See
e.g. crontab(5) under Debian 7 (wheezy).
* guix/scripts/package.scm (%profile-directory)
(guix-package): Also try LOGNAME if USER is unset.
Signed-off-by: Ludovic Courtès <ludo@gnu.org>
Fixes <http://bugs.gnu.org/17939>.
Reported by Taylan Ulrich Bayirli/Kammer <taylanbayirli@gmail.com>.
* guix/scripts/package.scm (canonicalize-profile): New procedure.
(%options): Use it for --profile.
* tests/guix-package.sh: Add test.
* guix/scripts/system.scm (read-operating-system) <catch handler>: Add
case for 'syntax-error'. Correct message for default case.
* guix/scripts/offload.scm (build-machines) <catch handler>: Add case
for 'syntax-error'.
* tests/guix-system.sh: New file.
* Makefile.am (SH_TESTS): Add it.
* guix/ui.scm (%guix-user-module): New variable.
(read/eval): Pass it as the second argument to 'eval'.
* guix/scripts/build.scm (options/resolve-packages): Add case for
'gexp?'.
* tests/guix-build.sh: Add tests.
* doc/guix.texi (Invoking guix build): Document '-e gexp'.
guxi build: Allow gexps to be passed to '-e'.
* guix/ui.scm (%guix-user-module): New variable.
(read/eval): Pass it as the second argument to 'eval'.
* guix/scripts/build.scm (options/resolve-packages): Add case for
'gexp?'.
* tests/guix-build.sh: Add tests.
* doc/guix.texi (Invoking guix build): Document '-e gexp'.
This makes 'guix package' et al. slightly less verbose, by not emitting
"@ substituter-started" lines and similar.
* guix/scripts/build.scm (set-build-options-from-command-line): Pass
#:print-build-trace.
(%default-options): Add 'print-build-trace?'.
* guix/pk-crypto.scm (string->canonical-sexp, sign, generate-key): Pass
the procedure name as the first argument to 'throw'.
(gcrypt-error-printer): New procedure.
<top level>: Add call to 'set-exception-printer!'.
* guix/nar.scm (restore-one-item): Add 'proc' parameter to 'catch'
handler for 'gcry-error.
* guix/scripts/archive.scm (%options, generate-key-pair, authorize-key):
Likewise.
* guix/scripts/substitute-binary.scm (narinfo-signature->canonical-sexp):
Likewise.
Fixes <http://bugs.gnu.org/17312>.
* guix/scripts/authenticate.scm (guix-authenticate): Add calls to
'set-port-encoding!' and 'set-port-conversion-strategy!'. Wrap body
in 'with-fluids' form that sets '%default-port-encoding' and
'%default-port-conversion-strategy'.
* tests/guix-authenticate.sh: Add test.
* tests/pk-crypto.scm ("hash corrupt due to restrictive locale
encoding"): Add reference to bug.
Fixes situations where the remote 'guix build' is invoked before the
.drv has been completely copied, as reported at
<https://lists.gnu.org/archive/html/guix-devel/2014-04/msg00174.html>.
In some cases 'send-files' would return before the other end is done
importing the files, and so the subsequent 'guix build' invocation would
just miss the .drv file it refers to.
* guix/utils.scm (call-with-decompressed-port): Don't close PORT.
(call-with-compressed-output-port): Likewise.
* tests/utils.scm ("compressed-output-port + decompressed-port"): Adjust
accordingly.
* guix/scripts/offload.scm (send-files): Add explicit (close-pipe pipe)
call.
(retrieve-files): Likewise.
* guix/scripts/offload.scm (remove-gc-root): Rename to...
(remove-gc-roots): ... this.
[builder]: Use 'scandir' and remove all the files starting with
%GC-ROOT-FILE.
(transfer-and-offload): Adjust to renaming; remove
'false-if-exception' wraps.
* build-aux/hydra/demo-os.scm: New file.
* Makefile.am (EXTRA_DIST): Add it.
* build-aux/hydra/gnu-system.scm (qemu-jobs): New procedure.
(hydra-jobs): Use it.
* guix/scripts/system.scm (read-operating-system): Export.
* guix/pki.scm (write-acl): New procedure.
(ensure-acl): Use it. Fixes a regression introduced in 39831f1,
whereby 'ensure-acl' would yield a wrong-type-arg error.
* guix/scripts/archive.scm (authorize-key): Use 'write-acl'.
Before that, there was a small time window during which the GC could
wipe the .drv (before 'guix build' has been called), or the build
result (before 'retrieve-files' has started.)
* guix/scripts/offload.scm (remote-pipe): Add #:quote? parameter and
honor it.
(%gc-root-file): New variable.
(register-gc-root, remove-gc-root): New procedures.
(offload): Adjust comment. Run 'guix build' with '-r %GC-ROOT-FILE'.
(transfer-and-offload): Call 'register-gc-root' before
sending (derivation-file-name DRV). Call 'remove-gc-root' after the
call to 'offload' or 'retrieve-files'.
(send-files): Call 'remote-pipe' with #:quote? #f.
(retrieve-files): Likewise.
* guix/scripts/package.scm (search-path-environment-variables)[manifest-entry->package]:
Use 'find-best-packages-by-name' instead of 'find-packages-by-name'.
On a profile with 140 packages, this reduces execution time of this
procedure from 5.8 seconds to 2.9 seconds (50% improvement.)
* guix/scripts/package.scm (maybe-register-gc-root): New procedure.
* tests/guix-package.sh (profile): Grep the output of "guix gc
--list-live" in a couple of places.
* guix/pki.scm (acl-entry-sexp, acl-sexp): Remove.
(public-keys->acl, current-acl): Return a native sexp.
(acl->public-keys, authorized-key?): Expect ACL to be a native sexp.
* guix/scripts/archive.scm (authorize-key): Convert ACL to
canonical-sexp when writing it.
* guix/scripts/substitute-binary.scm (guix-substitute-binary) <--query>:
Cache the result of (current-acl); pass it to 'valid-narinfo?' calls.
This saves 12% wall-clock time for "guix build emacs -n".
* guix/nar.scm (restore-file-set)[assert-valid-signature]: Rewrite in
terms of 'signature-case'.
* guix/scripts/substitute-binary.scm (narinfo-signature->canonical-sexp):
Call 'leave' instead of 'raise' when SIGNATURE is invalid.
(&nar-signature-error, &nar-invalid-hash-error): Remove.
(assert-valid-signature): Add 'narinfo' parameter; remove 'port'.
Rewrite in terms of 'signature-case' and 'leave'. Mention NARINFO's
URI in error messages. Adjust caller.
(narinfo-sha256): New procedure.
(assert-valid-narinfo): Use it.
(valid-narinfo?): Rewrite using 'narinfo-sha256' and
'signature-case'.
* tests/substitute-binary.scm (assert-valid-signature,
test-error-condition): Remove.
("corrupt signature data", "unauthorized public key", "invalid
signature"): Remove.
* guix/scripts/substitute-binary.scm (narinfo-signature->canonical-sexp):
Catch 'gcry-error' around 'string->canonical-sexp' call, and re-raise
as a SRFI-35 &message and &nar-signature-error.
(narinfo-maker): Handle when SIGNATURE is #f or an invalid canonical
sexp.
(&nar-signature-error, &nar-invalid-hash-error): New variables.
(assert-valid-signature): Use them. Expect 'signature' to be a
canonical sexp.
(read-narinfo): Remove authentication and authorization checks.
(%signature-line-rx): New variable.
(assert-valid-narinfo, valid-narinfo?): New procedures.
(guix-substitute-binary): Wrap body in 'with-error-handling'.
[valid?]: New procedure.
<--query>: Show only store items of narinfos that match
'valid-narinfo?'.
<--substitute>: Call 'assert-valid-narinfo'.
* tests/substitute-binary.scm (test-error*): Use 'test-equal'.
(%keypair): Remove.
(%public-key, %private-key): Load from signing-key.{pub,sec}.
(signature-body): Add #:public-key parameter.
(call-with-narinfo): New procedure.
(with-narinfo): New macro.
("corrupt signature data", "unauthorized public key", "invalid
signature"): Make the first argument to 'assert-valid-signature' a
canonical sexp.
("invalid hash", "valid read-narinfo", "valid write-narinfo"):
Remove.
("query narinfo with invalid hash", "query narinfo signed with
authorized key", "query narinfo signed with unauthorized key",
"substitute, invalid hash", "substitute, unauthorized key"): New
tests.
* guix/scripts/substitute-binary.scm (<narinfo>)[uri-base]: New field.
(narinfo-maker): Pass CACHE-URL as the 'uri-base' value.
(string->narinfo): Add 'cache-uri' parameter.
(lookup-narinfo)[cache-entry]: Switch to version 1. Add 'cache-uri'
field. Adjust body accordingly.
(remove-expired-cached-narinfos): Switch to version 1 by default.
* guix/scripts/substitute-binary.scm (<narinfo>): Add the 'signature'
and 'contents' fields.
(narinfo-signature->canonical-sexp): New function.
(narinfo-maker): Add the 'signature' argument and use it.
(assert-valid-signature): New function.
(read-narinfo): Support the Signature field.
(write-narinfo): Use 'narinfo-contents'.
(%allow-unauthenticated-substitutes?): New variable.
* guix/base64.scm, tests/base64.scm, tests/substitute-binary.scm: New files.
* Makefile.am (SCM_TESTS): Add tests/base64.scm and
tests/substitute-binary.scm.
(MODULES): Add guix/base64.scm.
* test-env.in: Set 'GUIX_ALLOW_UNAUTHENTICATED_SUBSTITUTES'.
* guix/scripts/offload.scm (transfer-and-offload): Use 'upload' lock
instead of 'bandwidth' around 'send-files' calls, and 'download' lock
around 'retrieve-files' call.
* guix/scripts/offload.scm (remote-pipe): Remove '-z' lsh command line
argument. This makes transfers almost an order of magnitude slower.
OpenSSH's ssh(1) man page notes: "Compression is desirable on modem lines
and other slow connections, but will only slow down things on fast
networks." See also
<http://www.spikelab.org/blog/transfer-largedata-scp-tarssh-tarnc-compared.html>.
* guix/scripts/authenticate.scm (guix-authenticate): Add clauses
for ("rsautl" "-sign" "-inkey" key) and ("rsautl" "-verify" "-inkey" _
"-pubin").
* tests/guix-authenticate.sh (hash): Add test using -sign and -verify in
a pipeline.
* guix/scripts/authenticate.scm (read-canonical-sexp): Change to expect
a port instead of a file name.
(read-hash-data): Likewise.
(sign-with-key, validate-signature): New procedures.
(guix-authenticate): Rewrite in terms of these two procedures.
* guix/utils.scm (decompressed-port, compressed-port): New procedures.
* guix/scripts/substitute-binary.scm (decompressed-port): Remove.
(guix-substitute-binary): Pass a symbol or #f as the first argument to
'decompress-port'.
* tests/utils.scm ("compressed-port, decompressed-port, non-file"): New
test.
* guix/pk-crypto.scm (gcrypt-version): New procedure.
* guix/scripts/archive.scm (%key-generation-parameters): New variable.
(%options) <generate-key>: Use it.
* tests/pk-crypto.scm ("sign + verify, Ed25519"): Skip if using gcrypt < 1.6.0.
* guix/scripts/offload.scm (with-error-to-port): New macro.
(remote-pipe): Add #:error-port parameter. Use 'with-error-to-port'
around 'open-pipe*' call.
(build-log-port): New procedure.
(offload): Change #:log-port to default to (build-log-port). Call
'remote-pipe' with #:error-port LOG-PORT.
* guix/scripts/substitute-binary.scm (fetch): Add #:quiet-404?
parameter. Upon &http-get-error, re-raise C if the QUIET-404? is
true and the code is 404.
(fetch-narinfo): Pass #:quiet-404? #t.
* guix/pk-crypto.scm (bytevector->hash-data): Add #:key-type parameter.
Use the 'pkcs1' flag when KEY-TYPE is 'rsa', and 'rfc6979' when
KEY-TYPE is 'ecc' or 'dsa'.
(key-type): New procedure.
* guix/scripts/authenticate.scm (read-hash-data): Add 'key-type'
parameter. Pass it to 'bytevector->hash-data'. Adjust caller
accordingly.
* tests/pk-crypto.scm (%ecc-key-pair): New variable.
("key-type"): New test.
("sign + verify"): Pass #:key-type to 'bytevector->hash-data'.
("sign + verify, Ed25519"): New test.
* guix/scripts/offload.scm (offload): Remove default value for
'build-timeout'. Pass '--timeout' to the remote 'guix build'
process.
(transfer-and-offload, process-request): Remove default value for
'build-timeout'.
* guix/scripts/offload.scm (transfer-and-offload): New procedure, with
core formerly in 'process-request'.
(choose-build-machine): Remove 'requirements' parameter.
(process-request): Reply 'decline' when none of MACHINES matches the
requirements, and 'postpone' when MACHINES are busy.
* guix/scripts/offload.scm (machine-choice-lock-file,
machine-slot-file, acquire-build-slot, release-build-slot): New
procedures.
(choose-build-machine): Operate with (machine-choice-lock-file)
taken. Acquire a build slot for each of MACHINES. Release those not
used.
* guix/scripts/offload.scm (lock-machine, unlock-machine): Remove.
(lock-file, unlock-file): New procedures.
(with-file-lock): New macro.
(with-machine-lock): Rewrite in terms of 'with-file-lock'.
* guix/scripts/offload.scm (machine-lock-file, lock-machine,
unlock-machine): New procedures.
(with-machine-lock): New macro.
(process-request): Wrap 'send-files' and 'retrieve-files' calls in
'with-machine-lock'.
* guix/http-client.scm (&http-get-error): New condition type.
(http-fetch): Raise it instead of using 'error'.
* guix/scripts/substitute-binary.scm (fetch) <http>: Wrap body into
'guard' form; gracefully handle 'http-get-error?' conditions.
* guix/scripts/offload.scm (machine-load, machine-less-loaded?,
machine-less-loaded-or-faster?): New procedures.
(choose-build-machine): Use 'machine-less-loaded-or-faster?' when
sorting. Return the head of MACHINES unless it's loaded is >= 2.
* guix/scripts/hash.scm (show-help): Add --recursive.
(%options): Likewise.
(guix-hash)[file-hash]: New procedure. Honor --recursive.
Use it.
* guix/nar.scm (write-file): Add missing field to the &nar-error
condition raised upon unsupported file type; change its message to be
more descriptive.
* tests/guix-hash.sh: Add tests with -r.
* doc/guix.texi (Invoking guix hash): Document --recursive.
* guix/scripts/system.scm: New file.
* Makefile.am (MODULES): Add it.
* po/POTFILES.in: Likewise.
* doc/guix.texi (Using the Configuration System): Link to "Invoking guix
system".
(Invoking guix system): New node.
* guix/scripts/offload.scm (offload): Add 'log-port' keyword parameter.
Handle log display here. Return the result of (close-pipe pipe).
(process-request): Adjust 'offload' call site accordingly. Call
'retrieve-files' only when 'offload' returns zero; exit when 'offload'
returns non-zero.
* nix/nix-daemon/guix-daemon.cc (GUIX_OPT_NO_BUILD_HOOK): New macro.
(options): Add '--no-build-hook'.
(parse_opt): Handle it.
(main)[HAVE_DAEMON_OFFLOAD_HOOK]: Set 'useBuildHook' by default.
Set $NIX_BUILD_HOOK to our offload hook unless otherwise specified.
[!HAVE_DAEMON_OFFLOAD_HOOK]: Clear 'useBuildHook'.
* pre-inst-env.in: Set and export NIX_BUILD_HOOK.
* nix/scripts/offload.in, guix/scripts/offload.scm: New files.
* guix/ui.scm (show-guix-help)[internal?]: Add "offload".
* config-daemon.ac: Call 'GUIX_CHECK_UNBUFFERED_CBIP'.
Instantiate 'nix/scripts/offload'. Set 'BUILD_DAEMON_OFFLOAD'
conditional, and optionally define 'HAVE_DEAMON_OFFLOAD_HOOK' cpp
macro.
* daemon.am (nodist_pkglibexec_SCRIPTS)[BUILD_DAEMON_OFFLOAD]: Add it.
* Makefile.am (MODULES)[BUILD_DAEMON_OFFLOAD]: Add
'guix/scripts/offload.scm'.
(EXTRA_DIST)[!BUILD_DAEMON_OFFLOAD]: Likewise.
* m4/guix.m4 (GUIX_CHECK_UNBUFFERED_CBIP): New macro.
* doc/guix.texi (Setting Up the Daemon): Move most of the body to...
(Build Environment Setup): ... this. New subsection.
(Daemon Offload Setup): New subsection.
* guix/pki.scm (signature-subject, signature-signed-data,
valid-signature?): New procedures.
* guix/scripts/authenticate.scm (guix-authenticate): Adjust to use
them.
* nix-upstream: Update sub-module.
* daemon.am (libutil_a_SOURCES): Add affinity.cc.
(libutil_headers): Add affinity.hh.
(libexec_PROGRAMS, nix_setuid_helper_SOURCES,
nix_setuid_helper_CPPFLAGS, nix_setuid_helper_LDADD): Remove.
* doc/guix.texi (Setting Up the Daemon): Remove paragraph about
'nix-setuid-helper'.
* guix/scripts/substitute-binary.scm (guix-substitute-binary): Exit 0 when
%CACHE-URL has an HTTP scheme and looking up its host fails.
Always print a newline to stdout when starting.
* guix/pki.scm (ensure-acl): Make sure the directory of %ACL-FILE
exists.
* guix/scripts/archive.scm (generate-key-pair): Likewise for
%PUBLIC-KEY-FILE.
* guix/scripts/package.scm (leave-on-EPIPE): New macro.
(guix-package): Use it for 'list-installed', 'list-available', and
'--list-generations'.
* tests/guix-package.sh: Add test.
* guix/scripts/archive.scm (authorize-key): New procedure.
(guix-archive): Call it when OPTS contains 'authorize-key'.
* tests/guix-archive.sh: Add test with invalid public key.
* guix/pki.scm: Export '%acl-file'.
* doc/guix.texi (Invoking guix archive): Make it clear that '--import'
works only with authorized keys. Document '--authorize'.
* guix/scripts/authenticate.scm (signature-sexp): Remove.
(guix-authenticate): Upon '-verify', check whether the signature's
public key passes 'authorized-key?'.
* guix/scripts/authenticate.scm (signature-sexp): New procedure.
(guix-authenticate): Use it to produce the signature. Adjust
verification code accordingly.
* tests/store.scm ("import corrupt path"): Adjust test accordingly.
* guix/pk-crypto.scm: Rename procedures, variables, etc. from
'gcry-sexp' to 'canonical-sexp'. Add comment with references.
* guix/scripts/authenticate.scm, tests/pk-crypto.scm: Adjust
accordingly.
* guix/scripts/package.scm (%options): Adapt option processors to accept and
return a second seed value: 'arg-handler', which handles bare arguments (if
not false). The install, remove, and upgrade option processors return an
arg-handler that repeat the same operation. All other option processors
return #f as the arg-handler. Make the arguments to install and remove
optional. The upgrade option processor deletes (upgrade . #f) from the
alist before adding a new entry.
(guix-package): Procedures passed to 'args-fold*' accept the new seed value
'arg-handler'. The 'operand-proc' uses 'arg-handler' (if not false).
* doc/guix.texi (Invoking guix package): Update docs.
* tests/guix-package.sh: Add test.
* guix/scripts/pull.scm (unpack)[builder](compile-file*): Remove.
(call-with-process, p-for-each): New procedures. Use them to compile
files in parallel.
Reported by Arne Babenhauserheide <arne.babenhauserheide@kit.edu>.
* guix/scripts/pull.scm (unpack)[builder](compile-file*): Change to run
'compile-file' in a child process. This limits memory usage; before
that memory usage was proportional to the number of files to compile.
* guix/scripts/substitute-binary.scm (n-par-map*): New procedure.
(guix-substitute-binary): Use it instead of 'n-par-map'.
Reported by Nikita Karetnikov and Eric Bavier.
* guix/ui.scm (read/eval): New procedure.
(read/eval-package-expression): Use it.
* guix/scripts/build.scm (derivations-from-package-expressions): Rename to...
(derivation-from-expression): ... this. Accept procedures, under the
assumption that they are monadic thunk.
(show-help): Adjust accordingly.
(guix-build): Ditto.
* tests/guix-build.sh: Add test.
* doc/guix.texi (Invoking guix build): Augment description of '-e'.
* guix/scripts/substitute-binary.scm (with-timeout): Update comment to
mention the fix's commit ID.
(fetch): In the 'with-timeout' handler, close PORT only one Guile
versions < 2.0.9.39. Before that, on Guile >= 2.0.9.39, the HTTP
client would end up trying to read from a closed file descriptor.
* guix/scripts/substitute-binary.scm (%lookup-threads): New variable.
(guix-substitute-binary): Use 'n-par-map' instead of 'par-map' for
batch 'lookup-narinfo' calls.
Fixes <http://bugs.gnu.org/15756>.
* guix/profiles.scm (<manifest-pattern>): New record type.
(remove-manifest-entry): Remove.
(entry-predicate, manifest-matching-entries): New procedures.
(manifest-remove): Accept a list of <manifest-pattern>.
(manifest-installed?): Replace 'name' parameter by 'pattern', a
<manifest-pattern>.
* guix/scripts/package.scm (options->removable): Return a list of
<manifest-pattern>.
(guix-package)[process-action]: Use 'manifest-matching-entries' to
compute the list of packages to remove.
* tests/profiles.scm: New file.
* Makefile.am (SCM_TESTS): Add it.
* guix/scripts/package.scm (options->removable): New procedure.
(guix-package)[process-actions]: Use it. Rename 'remove*' to 'remove'
and 'install*' to 'install'.
* guix/ui.scm (package-specification->name+version+output): New
procedure.
* guix/scripts/package.scm (specification->package+output): Use it.
* tests/ui.scm ("package-specification->name+version+output"): New test.
* guix/scripts/package.scm (<manifest-entry>): Add 'inputs' field.
(manifest=?, lower-input): New procedure.
(profile-derivation)[builder]: Add #:log-port argument to
'union-build'.
[ensure-valid-input]: Remove.
Add each entry's inputs to the input list.
(options->installable): Return just the list of entries.
[package->manifest-entry]: Set 'inputs' field.
[canonicalize-deps]: Rename to...
[deduplicate]: ... this. Remove input fiddling.
(guix-package)[process-actions]: Use 'manifest=?' to compare the new
and old manifests. Pass directly PROF-DRV to 'show-what-to-build'.
Pass #:print-build-trace #f to 'set-build-options'.
* guix/scripts/package.scm (%user-environment-directory): Rename to...
(%user-profile-directory): ... this. Update users accordingly.
(profile-derivation): Use the term "profile" instead of "user
environment", and use "profile" as the derivation name.
* guix/scripts/package.scm (<manifest>, <manifest-entry>): New record
types.
(make-manifest, read-manifest, manifest->sexp, sexp->manifest,
read-manifest, write-manifest, remove-manifest-entry, manifest-remove,
manifest-installed?): New procedures.
(profile-derivation): Take a manifest as the second parameter. Use
'manifest->sexp'. Expect <manifest-entry> objects instead of
"tuples". Adjust callers accordingly.
(search-path-environment-variables): Changes 'packages' parameter to
'entries'. Rename 'package-in-manifest->package' to
'manifest-entry->package'; expect <manifest-entry> objects.
(display-search-paths): Rename 'packages' to 'entries'.
(options->installable): Change 'installed' to 'manifest'. Have
'canonicalize-deps' return name/path tuples instead of raw packages.
Rename 'package->tuple' to 'package->manifest-entry'. Use
<manifest-entry> objects instead of tuples.
(guix-package)[process-actions]: Likewise. Rename 'packages' to
'entries'.
[process-query]: Use 'manifest-entries' instead of
'manifest-packages'.
* guix/scripts/package.scm (find-package): Rename to...
(specification->package+output): ... this. Rename 'name' parmameter
to 'spec'. Return a package and output name instead of a tuple.
(options->installable): New procedure
(guix-package)[process-actions]: Use it, and remove corresponding
code.
* guix/scripts/package.scm (switch-to-previous-generation): New function.
(roll-back): Use the new function instead of 'switch-link'.
(show-help): Add '--delete-generations'.
(%options): Likewise.
(guix-package)[process-actions]: Add 'current-generation-number',
'display-and-delete', and 'delete-generation'. Add support for
'--delete-generations', and reindent the code.
* tests/guix-package.sh: Test '--delete-generations'.
* doc/guix.texi (Invoking guix-package): Document '--delete-generations'.
* guix/scripts/package.scm (guix-package)[process-query]: Show that a
generation is the current one if the profile points to it.
* tests/guix-package.sh: Test it.
* guix/scripts/package.scm (guix-package)[process-query]: Change
'list-generation' to not list the zeroth generation.
* tests/guix-package.sh: Test it.
* doc/guix.texi (Invoking guix package): Document it, and use the
right term when talking about generations.
Eric Bavier