;;; GNU Guix --- Functional package management for GNU ;;; Copyright © 2012, 2013 Ludovic Courtès <ludo@gnu.org> ;;; ;;; This file is part of GNU Guix. ;;; ;;; GNU Guix is free software; you can redistribute it and/or modify it ;;; under the terms of the GNU General Public License as published by ;;; the Free Software Foundation; either version 3 of the License, or (at ;;; your option) any later version. ;;; ;;; GNU Guix is distributed in the hope that it will be useful, but ;;; WITHOUT ANY WARRANTY; without even the implied warranty of ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;;; GNU General Public License for more details. ;;; ;;; You should have received a copy of the GNU General Public License ;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>. (define-module (guix utils) #:use-module (guix config) #:use-module (srfi srfi-1) #:use-module (srfi srfi-9) #:use-module (srfi srfi-26) #:use-module (srfi srfi-39) #:use-module (srfi srfi-60) #:use-module (rnrs bytevectors) #:use-module ((rnrs io ports) #:select (put-bytevector)) #:use-module ((guix build utils) #:select (dump-port)) #:use-module (ice-9 vlist) #:use-module (ice-9 format) #:autoload (ice-9 popen) (open-pipe*) #:autoload (ice-9 rdelim) (read-line) #:use-module (ice-9 regex) #:use-module (ice-9 match) #:use-module (ice-9 format) #:autoload (system foreign) (pointer->procedure) #:export (bytevector->base16-string base16-string->bytevector %nixpkgs-directory nixpkgs-derivation nixpkgs-derivation* compile-time-value memoize default-keyword-arguments substitute-keyword-arguments <location> location location? location-file location-line location-column source-properties->location gnu-triplet->nix-system %current-system %current-target-system version-compare version>? guile-version>? package-name->name+version string-tokenize* file-extension file-sans-extension call-with-temporary-output-file fold2 filtered-port)) ;;; ;;; Compile-time computations. ;;; (define-syntax compile-time-value (syntax-rules () "Evaluate the given expression at compile time. The expression must evaluate to a simple datum." ((_ exp) (let-syntax ((v (lambda (s) (let ((val exp)) (syntax-case s () (_ #`'#,(datum->syntax s val))))))) v)))) ;;; ;;; Base 16. ;;; (define (bytevector->base16-string bv) "Return the hexadecimal representation of BV's contents." (define len (bytevector-length bv)) (let-syntax ((base16-chars (lambda (s) (syntax-case s () (_ (let ((v (list->vector (unfold (cut > <> 255) (lambda (n) (format #f "~2,'0x" n)) 1+ 0)))) v)))))) (define chars base16-chars) (let loop ((i 0) (r '())) (if (= i len) (string-concatenate-reverse r) (loop (+ 1 i) (cons (vector-ref chars (bytevector-u8-ref bv i)) r)))))) (define base16-string->bytevector (let ((chars->value (fold (lambda (i r) (vhash-consv (string-ref (number->string i 16) 0) i r)) vlist-null (iota 16)))) (lambda (s) "Return the bytevector whose hexadecimal representation is string S." (define bv (make-bytevector (quotient (string-length s) 2) 0)) (string-fold (lambda (chr i) (let ((j (quotient i 2)) (v (and=> (vhash-assv chr chars->value) cdr))) (if v (if (zero? (logand i 1)) (bytevector-u8-set! bv j (arithmetic-shift v 4)) (let ((w (bytevector-u8-ref bv j))) (bytevector-u8-set! bv j (logior v w)))) (error "invalid hexadecimal character" chr))) (+ i 1)) 0 s) bv))) ;;; ;;; Filtering & pipes. ;;; (define (filtered-port command input) "Return an input port where data drained from INPUT is filtered through COMMAND (a list). In addition, return a list of PIDs that the caller must wait. When INPUT is a file port, it must be unbuffered; otherwise, any buffered data is lost." (let loop ((input input) (pids '())) (if (file-port? input) (match (pipe) ((in . out) (match (primitive-fork) (0 (close-port in) (close-port (current-input-port)) (dup2 (fileno input) 0) (close-port (current-output-port)) (dup2 (fileno out) 1) (apply execl (car command) command)) (child (close-port out) (values in (cons child pids)))))) ;; INPUT is not a file port, so fork just for the sake of tunneling it ;; through a file port. (match (pipe) ((in . out) (match (primitive-fork) (0 (dynamic-wind (const #t) (lambda () (close-port in) (dump-port input out)) (lambda () (false-if-exception (close out)) (primitive-exit 0)))) (child (close-port out) (loop in (cons child pids))))))))) ;;; ;;; Nixpkgs. ;;; (define %nixpkgs-directory (make-parameter ;; Capture the build-time value of $NIXPKGS. (or %nixpkgs (and=> (getenv "NIXPKGS") (lambda (val) ;; Bail out when passed an empty string, otherwise ;; `nix-instantiate' will sit there and attempt to read ;; from its standard input. (if (string=? val "") #f val)))))) (define* (nixpkgs-derivation attribute #:optional (system (%current-system))) "Return the derivation path of ATTRIBUTE in Nixpkgs." (let* ((p (open-pipe* OPEN_READ (or (getenv "NIX_INSTANTIATE") %nix-instantiate) "-A" attribute (%nixpkgs-directory) "--argstr" "system" system)) (l (read-line p)) (s (close-pipe p))) (and (zero? (status:exit-val s)) (not (eof-object? l)) l))) (define-syntax-rule (nixpkgs-derivation* attribute) "Evaluate the given Nixpkgs derivation at compile-time." (compile-time-value (nixpkgs-derivation attribute))) ;;; ;;; Miscellaneous. ;;; (define (memoize proc) "Return a memoizing version of PROC." (let ((cache (make-hash-table))) (lambda args (let ((results (hash-ref cache args))) (if results (apply values results) (let ((results (call-with-values (lambda () (apply proc args)) list))) (hash-set! cache args results) (apply values results))))))) (define (default-keyword-arguments args defaults) "Return ARGS augmented with any keyword/value from DEFAULTS for keywords not already present in ARGS." (let loop ((defaults defaults) (args args)) (match defaults ((kw value rest ...) (loop rest (if (assoc-ref kw args) args (cons* kw value args)))) (() args)))) (define-syntax substitute-keyword-arguments (syntax-rules () "Return a new list of arguments where the value for keyword arg KW is replaced by EXP. EXP is evaluated in a context where VAR is boud to the previous value of the keyword argument." ((_ original-args ((kw var) exp) ...) (let loop ((args original-args) (before '())) (match args ((kw var rest (... ...)) (loop rest (cons* exp kw before))) ... ((x rest (... ...)) (loop rest (cons x before))) (() (reverse before))))))) (define (gnu-triplet->nix-system triplet) "Return the Nix system type corresponding to TRIPLET, a GNU triplet as returned by `config.guess'." (let ((triplet (cond ((string-match "^i[345]86-(.*)$" triplet) => (lambda (m) (string-append "i686-" (match:substring m 1)))) (else triplet)))) (cond ((string-match "^([^-]+)-([^-]+-)?linux-gnu.*" triplet) => (lambda (m) ;; Nix omits `-gnu' for GNU/Linux. (string-append (match:substring m 1) "-linux"))) ((string-match "^([^-]+)-([^-]+-)?([[:alpha:]]+)([0-9]+\\.?)*$" triplet) => (lambda (m) ;; Nix strip the version number from names such as `gnu0.3', ;; `darwin10.2.0', etc., and always strips the vendor part. (string-append (match:substring m 1) "-" (match:substring m 3)))) (else triplet)))) (define %current-system ;; System type as expected by Nix, usually ARCHITECTURE-KERNEL. ;; By default, this is equal to (gnu-triplet->nix-system %host-type). (make-parameter %system)) (define %current-target-system ;; Either #f or a GNU triplet representing the target system we are ;; cross-building to. (make-parameter #f)) (define version-compare (let ((strverscmp (let ((sym (or (dynamic-func "strverscmp" (dynamic-link)) (error "could not find `strverscmp' (from GNU libc)")))) (pointer->procedure int sym (list '* '*))))) (lambda (a b) "Return '> when A denotes a newer version than B, '< when A denotes a older version than B, or '= when they denote equal versions." (let ((result (strverscmp (string->pointer a) (string->pointer b)))) (cond ((positive? result) '>) ((negative? result) '<) (else '=)))))) (define (version>? a b) "Return #t when A denotes a newer version than B." (eq? '> (version-compare a b))) (define (guile-version>? str) "Return #t if the running Guile version is greater than STR." ;; Note: Using (version>? (version) "2.0.5") or similar doesn't work, ;; because the result of (version) can have a prefix, like "2.0.5-deb1". (version>? (string-append (major-version) "." (minor-version) "." (micro-version)) str)) (define (package-name->name+version name) "Given NAME, a package name like \"foo-0.9.1b\", return two values: \"foo\" and \"0.9.1b\". When the version part is unavailable, NAME and #f are returned. The first hyphen followed by a digit is considered to introduce the version part." ;; See also `DrvName' in Nix. (define number? (cut char-set-contains? char-set:digit <>)) (let loop ((chars (string->list name)) (prefix '())) (match chars (() (values name #f)) ((#\- (? number? n) rest ...) (values (list->string (reverse prefix)) (list->string (cons n rest)))) ((head tail ...) (loop tail (cons head prefix)))))) (define (file-extension file) "Return the extension of FILE or #f if there is none." (let ((dot (string-rindex file #\.))) (and dot (substring file (+ 1 dot) (string-length file))))) (define (file-sans-extension file) "Return the substring of FILE without its extension, if any." (let ((dot (string-rindex file #\.))) (if dot (substring file 0 dot) file))) (define (string-tokenize* string separator) "Return the list of substrings of STRING separated by SEPARATOR. This is like `string-tokenize', but SEPARATOR is a string." (define (index string what) (let loop ((string string) (offset 0)) (cond ((string-null? string) #f) ((string-prefix? what string) offset) (else (loop (string-drop string 1) (+ 1 offset)))))) (define len (string-length separator)) (let loop ((string string) (result '())) (cond ((index string separator) => (lambda (offset) (loop (string-drop string (+ offset len)) (cons (substring string 0 offset) result)))) (else (reverse (cons string result)))))) (define (call-with-temporary-output-file proc) "Call PROC with a name of a temporary file and open output port to that file; close the file and delete it when leaving the dynamic extent of this call." (let* ((template (string-copy "guix-file.XXXXXX")) (out (mkstemp! template))) (dynamic-wind (lambda () #t) (lambda () (proc template out)) (lambda () (false-if-exception (close out)) (false-if-exception (delete-file template)))))) (define fold2 (case-lambda ((proc seed1 seed2 lst) "Like `fold', but with a single list and two seeds." (let loop ((result1 seed1) (result2 seed2) (lst lst)) (if (null? lst) (values result1 result2) (call-with-values (lambda () (proc (car lst) result1 result2)) (lambda (result1 result2) (loop result1 result2 (cdr lst))))))) ((proc seed1 seed2 lst1 lst2) "Like `fold', but with a two lists and two seeds." (let loop ((result1 seed1) (result2 seed2) (lst1 lst1) (lst2 lst2)) (if (or (null? lst1) (null? lst2)) (values result1 result2) (call-with-values (lambda () (proc (car lst1) (car lst2) result1 result2)) (lambda (result1 result2) (fold2 proc result1 result2 (cdr lst1) (cdr lst2))))))))) ;;; ;;; Source location. ;;; ;; A source location. (define-record-type <location> (make-location file line column) location? (file location-file) ; file name (line location-line) ; 1-indexed line (column location-column)) ; 0-indexed column (define location (memoize (lambda (file line column) "Return the <location> object for the given FILE, LINE, and COLUMN." (and line column file (make-location file line column))))) (define (source-properties->location loc) "Return a location object based on the info in LOC, an alist as returned by Guile's `source-properties', `frame-source', `current-source-location', etc." (let ((file (assq-ref loc 'filename)) (line (assq-ref loc 'line)) (col (assq-ref loc 'column))) ;; In accordance with the GCS, start line and column numbers at 1. Note ;; that unlike LINE and `port-column', COL is actually 1-indexed here... (location file (and line (+ line 1)) col)))