From 57db09aae73e3713a10c5253758d84e1046f80dc Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Thu, 23 Mar 2023 17:22:38 +0100 Subject: environment: Add '--nesting'. * guix/scripts/environment.scm (show-environment-options-help) (%options): Add '--nesting'. (options/resolve-packages): Handle it. (launch-environment/container): Add #:nesting? and honor it. [nesting-mappings]: New procedure. (guix-environment*): Add support for '--nesting'. * guix/scripts/shell.scm (profile-cached-gc-root): Special-case 'nesting?'. * tests/guix-environment-container.sh: Test it. * doc/guix.texi (Invoking guix shell): Document it. --- doc/guix.texi | 51 ++++++++++++++++++++++++++++ guix/scripts/environment.scm | 66 ++++++++++++++++++++++++++++++++++--- guix/scripts/shell.scm | 2 ++ tests/guix-environment-container.sh | 9 +++++ 4 files changed, 124 insertions(+), 4 deletions(-) diff --git a/doc/guix.texi b/doc/guix.texi index 4f72e2f34a..c0bd28fdae 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -6357,6 +6357,57 @@ cache (contrary to glibc in regular Guix usage) and set up the expected FHS directories: @file{/bin}, @file{/etc}, @file{/lib}, and @file{/usr} from the container's profile. +@cindex nested containers, for @command{guix shell} +@cindex container nesting, for @command{guix shell} +@item --nesting +@itemx -W +When used with @option{--container}, provide Guix @emph{inside} the +container and arrange so that it can interact with the build daemon that +runs outside the container. This is useful if you want, within your +isolated container, to create other containers, as in this sample +session: + +@example +$ guix shell -CW coreutils +[env]$ guix shell -C guile -- guile -c '(display "hello!\n")' +hello! +[env]$ exit +@end example + +The session above starts a container with @code{coreutils} programs +available in @env{PATH}. From there, we spawn @command{guix shell} to +create a @emph{nested} container that provides nothing but Guile. + +Another example is evaluating a @file{guix.scm} file that is untrusted, +as shown here: + +@example +guix shell -CW -- guix build -f guix.scm +@end example + +The @command{guix build} command as executed above can only access the +current directory. + +Under the hood, the @option{-W} option does several things: + +@itemize +@item +map the daemon's socket (by default +@file{/var/guix/daemon-socket/socket}) inside the container; +@item +map the whole store (by default @file{/gnu/store}) inside the container +such that store items made available by nested @command{guix} +invocations are visible; +@item +add the currently-used @command{guix} command to the profile in the +container, such that @command{guix describe} returns the same state +inside and outside the container; +@item +share the cache (by default @file{~/.cache/guix}) with the host, to +speed up operations such as @command{guix time-machine} and +@command{guix shell}. +@end itemize + @item --rebuild-cache @cindex caching, of profiles @cindex caching, in @command{guix shell} diff --git a/guix/scripts/environment.scm b/guix/scripts/environment.scm index a4939ea63c..ebfc05731c 100644 --- a/guix/scripts/environment.scm +++ b/guix/scripts/environment.scm @@ -31,6 +31,8 @@ (define-module (guix scripts environment) #:use-module (guix build utils) #:use-module (guix monads) #:use-module ((guix gexp) #:select (lower-object)) + #:autoload (guix describe) (current-profile current-channels) + #:autoload (guix channels) (guix-channel? channel-commit) #:use-module (guix scripts) #:use-module (guix scripts build) #:autoload (guix scripts pack) (symlink-spec-option-parser) @@ -49,9 +51,11 @@ (define-module (guix scripts environment) #:autoload (gnu packages) (specification->package+output) #:autoload (gnu packages bash) (bash) #:autoload (gnu packages bootstrap) (bootstrap-executable %bootstrap-guile) + #:autoload (gnu packages package-management) (guix) #:use-module (ice-9 match) #:autoload (ice-9 rdelim) (read-line) #:use-module (ice-9 vlist) + #:autoload (web uri) (string->uri uri-scheme) #:use-module (srfi srfi-1) #:use-module (srfi srfi-11) #:use-module (srfi srfi-26) @@ -108,6 +112,8 @@ (define (show-environment-options-help) -P, --link-profile link environment profile to ~/.guix-profile within an isolated container")) (display (G_ " + -W, --nesting make Guix available within the container")) + (display (G_ " -u, --user=USER instead of copying the name and home of the current user into an isolated container, use the name USER with home directory /home/USER")) @@ -238,6 +244,9 @@ (define %options (option '(#\N "network") #f #f (lambda (opt name arg result) (alist-cons 'network? #t result))) + (option '(#\W "nesting") #f #f + (lambda (opt name arg result) + (alist-cons 'nesting? #t result))) (option '(#\P "link-profile") #f #f (lambda (opt name arg result) (alist-cons 'link-profile? #t result))) @@ -342,6 +351,26 @@ (define (packages->outputs packages mode) (packages->outputs (load* file module) mode))) (('manifest . file) (manifest-entries (load-manifest file))) + (('nesting? . #t) + (if (assoc-ref opts 'profile) + '() + (let ((profile (and=> (current-profile) readlink*))) + (if (or (not profile) (not (store-path? profile))) + (begin + (warning (G_ "\ +could not add current Guix to the profile~%")) + '()) + (list (manifest-entry + (name "guix") + (version + (or (any (lambda (channel) + (and (guix-channel? channel) + (channel-commit channel))) + (current-channels)) + "0")) + (item profile) + (search-paths + (package-native-search-paths guix)))))))) (_ '())) opts) manifest-entry=?))) @@ -688,7 +717,8 @@ (define* (launch-environment/fork command profile manifest (define* (launch-environment/container #:key command bash user user-mappings profile manifest link-profile? network? - map-cwd? emulate-fhs? (setup-hook #f) + map-cwd? emulate-fhs? nesting? + (setup-hook #f) (symlinks '()) (white-list '())) "Run COMMAND within a container that features the software in PROFILE. Environment variables are set according to the search paths of MANIFEST. The @@ -704,6 +734,9 @@ (define* (launch-environment/container #:key command bash user user-mappings SETUP-HOOK is an additional setup procedure to be called, currently only used with the EMULATE-FHS? option. +When NESTING? is true, share all the store with the container and add Guix to +its profile, allowing its use from within the container. + LINK-PROFILE? creates a symbolic link from ~/.guix-profile to the environment profile. @@ -731,8 +764,26 @@ (define fhs-mappings ("/libexec" . "/usr/libexec") ("/share" . "/usr/share")))) - (mlet %store-monad ((reqs (inputs->requisites - (list (direct-store-path bash) profile)))) + (define (nesting-mappings) + ;; Files shared with the host when enabling nesting. + (cons* (file-system-mapping + (source (%store-prefix)) + (target source)) + (file-system-mapping + (source (cache-directory)) + (target source) + (writable? #t)) + (let ((uri (string->uri (%daemon-socket-uri)))) + (if (or (not uri) (eq? 'file (uri-scheme uri))) + (list (file-system-mapping + (source (%daemon-socket-uri)) + (target source))) + '())))) + + (mlet %store-monad ((reqs (if nesting? + (return '()) + (inputs->requisites + (list (direct-store-path bash) profile))))) (return (let* ((cwd (getcwd)) (home (getenv "HOME")) @@ -795,11 +846,14 @@ (define fhs-mappings (filter-map optional-mapping->fs %network-file-mappings) '()) - ;; Mappings for an FHS container. (if emulate-fhs? (filter-map optional-mapping->fs fhs-mappings) '()) + (if nesting? + (filter-map optional-mapping->fs + (nesting-mappings)) + '()) (map file-system-mapping->bind-mount mappings)))) (exit/status @@ -1013,6 +1067,7 @@ (define (guix-environment* opts) (network? (assoc-ref opts 'network?)) (no-cwd? (assoc-ref opts 'no-cwd?)) (emulate-fhs? (assoc-ref opts 'emulate-fhs?)) + (nesting? (assoc-ref opts 'nesting?)) (user (assoc-ref opts 'user)) (bootstrap? (assoc-ref opts 'bootstrap?)) (system (assoc-ref opts 'system)) @@ -1059,6 +1114,8 @@ (define-syntax-rule (with-store/maybe store exp ...) (leave (G_ "--no-cwd cannot be used without '--container'~%"))) (when emulate-fhs? (leave (G_ "'--emulate-fhs' cannot be used without '--container~%'"))) + (when nesting? + (leave (G_ "'--nesting' cannot be used without '--container~%'"))) (when (pair? symlinks) (leave (G_ "'--symlink' cannot be used without '--container~%'")))) @@ -1141,6 +1198,7 @@ (define manifest #:network? network? #:map-cwd? (not no-cwd?) #:emulate-fhs? emulate-fhs? + #:nesting? nesting? #:symlinks symlinks #:setup-hook (and emulate-fhs? diff --git a/guix/scripts/shell.scm b/guix/scripts/shell.scm index 92bbfb04d0..1b42cc2af0 100644 --- a/guix/scripts/shell.scm +++ b/guix/scripts/shell.scm @@ -389,6 +389,8 @@ (define (key->file key) (if (not file) (loop rest system file (cons spec specs)) (values #f #f))) + ((('nesting? . #t) . rest) + (loop rest system file (append specs '("nested guix")))) ((('load . ('package candidate)) . rest) (if (and (not file) (null? specs)) (loop rest system candidate specs) diff --git a/tests/guix-environment-container.sh b/tests/guix-environment-container.sh index 0475405a89..a30d6b7fb2 100644 --- a/tests/guix-environment-container.sh +++ b/tests/guix-environment-container.sh @@ -264,3 +264,12 @@ guix shell --bootstrap guile-bootstrap --container \ # An invalid symlink spec causes the command to fail. ! guix shell --bootstrap -CS bin/guile=/usr/bin/guile guile-bootstrap -- exit + +# Check whether '--nesting' works. +guix build hello -d +env="$(type -P pre-inst-env)" +if guix shell -C -D guix -- "$env" guix build hello -d # cannot work +then false; else true; fi +hello_drv="$(guix build hello -d)" +hello_drv_nested="$(cd "$(dirname env)" && guix shell --bootstrap -CW -D guix -- "$env" guix build hello -d)" +test "$hello_drv" = "$hello_drv_nested" -- cgit v1.2.3