~ruther/guix-local

9d3994f70095b46b95e6d05562f32c25be326772 — Ludovic Courtès 10 years ago 4fef1e8
gexp: 'local-file' resolves relative file names.

* guix/gexp.scm (<local-file>): Rename constructor to '%%local-file'.
Add 'absolute' field.
(%local-file, extract-directory, absolute-file-name): New procedures.
(current-source-directory): New macro.
(local-file): Adjust call to '%local-file'.
(local-file-absolute-file-name): New procedure.
(local-file-compiler): Force the 'absolute' field.
* tests/guix-system.sh: Test whether 'local-file' canonicalization
works.
* doc/guix.texi (G-Expressions): Adjust.
3 files changed, 87 insertions(+), 16 deletions(-)

M doc/guix.texi
M guix/gexp.scm
M tests/guix-system.sh
M doc/guix.texi => doc/guix.texi +3 -2
@@ 3489,8 3489,9 @@ content is directly passed as a string.
@deffn {Scheme Procedure} local-file @var{file} [@var{name}] @
   [#:recursive? #t]
Return an object representing local file @var{file} to add to the store; this
object can be used in a gexp.  @var{file} will be added to the store under @var{name}--by
default the base name of @var{file}.
object can be used in a gexp.  If @var{file} is a relative file name, it is looked
up relative to the source file where this form appears.  @var{file} will be added to
the store under @var{name}--by default the base name of @var{file}.

When @var{recursive?} is true, the contents of @var{file} are added recursively; if @var{file}
designates a flat file and @var{recursive?} is true, its contents are added, and its

M guix/gexp.scm => guix/gexp.scm +54 -12
@@ 35,6 35,7 @@
            local-file
            local-file?
            local-file-file
            local-file-absolute-file-name
            local-file-name
            local-file-recursive?



@@ 182,35 183,76 @@ cross-compiling.)"
;;; File declarations.
;;;

;; A local file name.  FILE is the file name the user entered, which can be a
;; relative file name, and ABSOLUTE is a promise that computes its canonical
;; absolute file name.  We keep it in a promise to compute it lazily and avoid
;; repeated 'stat' calls.
(define-record-type <local-file>
  (%local-file file name recursive?)
  (%%local-file file absolute name recursive?)
  local-file?
  (file       local-file-file)                    ;string
  (absolute   %local-file-absolute-file-name)     ;promise string
  (name       local-file-name)                    ;string
  (recursive? local-file-recursive?))             ;Boolean

(define* (local-file file #:optional (name (basename file))
                     #:key recursive?)
(define* (%local-file file promise #:optional (name (basename file))
                      #:key recursive?)
  ;; This intermediate procedure is part of our ABI, but the underlying
  ;; %%LOCAL-FILE is not.
  (%%local-file file promise name recursive?))

(define (extract-directory properties)
  "Extract the directory name from source location PROPERTIES."
  (match (assq 'filename properties)
    (('filename . (? string? file-name))
     (dirname file-name))
    (_
     #f)))

(define-syntax-rule (current-source-directory)
  "Expand to the directory of the current source file or #f if it could not
be determined."
  (extract-directory (current-source-location)))

(define (absolute-file-name file directory)
  "Return the canonical absolute file name for FILE, which lives in the
vicinity of DIRECTORY."
  (canonicalize-path
   (cond ((string-prefix? "/" file) file)
         ((not directory) file)
         ((string-prefix? "/" directory)
          (string-append directory "/" file))
         (else file))))

(define-syntax-rule (local-file file rest ...)
  "Return an object representing local file FILE to add to the store; this
object can be used in a gexp.  FILE will be added to the store under NAME--by
default the base name of FILE.
object can be used in a gexp.  If FILE is a relative file name, it is looked
up relative to the source file where this form appears.  FILE will be added to
the store under NAME--by default the base name of FILE.

When RECURSIVE? is true, the contents of FILE are added recursively; if FILE
designates a flat file and RECURSIVE? is true, its contents are added, and its
permission bits are kept.

This is the declarative counterpart of the 'interned-file' monadic procedure."
  ;; Canonicalize FILE so that if it's a symlink, it is resolved.  Failing to
  ;; do that, when RECURSIVE? is #t, we could end up creating a dangling
  ;; symlink in the store, and when RECURSIVE? is #f 'add-to-store' would just
  ;; throw an error, both of which are inconvenient.
  (%local-file (canonicalize-path file) name recursive?))
  (%local-file file
               (delay (absolute-file-name file (current-source-directory)))
               rest ...))

(define (local-file-absolute-file-name file)
  "Return the absolute file name for FILE, a <local-file> instance.  A
'system-error' exception is raised if FILE could not be found."
  (force (%local-file-absolute-file-name file)))

(define-gexp-compiler (local-file-compiler (file local-file?) system target)
  ;; "Compile" FILE by adding it to the store.
  (match file
    (($ <local-file> file name recursive?)
     (interned-file file name #:recursive? recursive?))))
    (($ <local-file> file (= force absolute) name recursive?)
     ;; Canonicalize FILE so that if it's a symlink, it is resolved.  Failing
     ;; to do that, when RECURSIVE? is #t, we could end up creating a dangling
     ;; symlink in the store, and when RECURSIVE? is #f 'add-to-store' would
     ;; just throw an error, both of which are inconvenient.
     (interned-file absolute name #:recursive? recursive?))))

(define-record-type <plain-file>
  (%plain-file name content references)

M tests/guix-system.sh => tests/guix-system.sh +30 -2
@@ 17,7 17,7 @@
# along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.

#
# Test the daemon and its interaction with 'guix substitute'.
# Test 'guix system', mostly error reporting.
#

set -e


@@ 26,7 26,15 @@ guix system --version

tmpfile="t-guix-system-$$"
errorfile="t-guix-system-error-$$"
trap 'rm -f "$tmpfile" "$errorfile"' EXIT

# Note: This directory is chosen outside $builddir so that relative file name
# canonicalization doesn't mess up with 'current-source-directory', used by
# 'local-file' ('load' forces 'relative' for
# %FILE-PORT-NAME-CANONICALIZATION.)
tmpdir="${TMPDIR:-/tmp}/t-guix-system-$$"
mkdir "$tmpdir"

trap 'rm -f "$tmpfile" "$errorfile" "$tmpdir"/*; rmdir "$tmpdir"' EXIT

# Reporting of syntax errors.



@@ 180,3 188,23 @@ make_user_config "users" "group-that-does-not-exist"
if guix system build "$tmpfile" -n 2> "$errorfile"
then false
else grep "supplementary group.*group-that-does-not-exist.*undeclared" "$errorfile"; fi

# Try 'local-file' and relative file name resolution.

cat > "$tmpdir/config.scm"<<EOF
(use-modules (gnu))
(use-service-modules networking)

(operating-system
  $OS_BASE
  (services (cons (tor-service (local-file "my-torrc"))
                  %base-services)))
EOF

cat > "$tmpdir/my-torrc"<<EOF
# This is an example file.
EOF

# In both cases 'my-torrc' should be properly resolved.
guix system build "$tmpdir/config.scm" -n
(cd "$tmpdir"; guix system build "config.scm" -n)