diff options
Diffstat (limited to 'guix/utils.scm')
| -rw-r--r-- | guix/utils.scm | 192 |
1 files changed, 9 insertions, 183 deletions
diff --git a/guix/utils.scm b/guix/utils.scm index 6c01edde21..c77da5d846 100644 --- a/guix/utils.scm +++ b/guix/utils.scm @@ -32,8 +32,9 @@ #:use-module (rnrs bytevectors) #:use-module (rnrs io ports) #:use-module ((rnrs bytevectors) #:select (bytevector-u8-set!)) + #:use-module (guix combinators) #:use-module ((guix build utils) #:select (dump-port)) - #:use-module ((guix build syscalls) #:select (errno mkdtemp!)) + #:use-module ((guix build syscalls) #:select (mkdtemp!)) #:use-module (ice-9 vlist) #:use-module (ice-9 format) #:autoload (ice-9 popen) (open-pipe*) @@ -43,12 +44,10 @@ #:use-module (ice-9 format) #:use-module ((ice-9 iconv) #:select (bytevector->string)) #:use-module (system foreign) + #:re-export (memoize) ; for backwards compatibility #:export (bytevector->base16-string base16-string->bytevector - compile-time-value - fcntl-flock - memoize strip-keyword-arguments default-keyword-arguments substitute-keyword-arguments @@ -82,10 +81,6 @@ call-with-temporary-output-file call-with-temporary-directory with-atomic-file-output - fold2 - fold-tree - fold-tree-leaves - split cache-directory readlink* edit-expression @@ -100,22 +95,6 @@ ;;; -;;; 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. ;;; @@ -361,94 +340,9 @@ This procedure returns #t on success." ;;; -;;; Advisory file locking. -;;; - -(define %struct-flock - ;; 'struct flock' from <fcntl.h>. - (list short ; l_type - short ; l_whence - size_t ; l_start - size_t ; l_len - int)) ; l_pid - -(define F_SETLKW - ;; On Linux-based systems, this is usually 7, but not always - ;; (exceptions include SPARC.) On GNU/Hurd, it's 9. - (compile-time-value - (cond ((string-contains %host-type "sparc") 9) ; sparc-*-linux-gnu - ((string-contains %host-type "linux") 7) ; *-linux-gnu - (else 9)))) ; *-gnu* - -(define F_SETLK - ;; Likewise: GNU/Hurd and SPARC use 8, while the others typically use 6. - (compile-time-value - (cond ((string-contains %host-type "sparc") 8) ; sparc-*-linux-gnu - ((string-contains %host-type "linux") 6) ; *-linux-gnu - (else 8)))) ; *-gnu* - -(define F_xxLCK - ;; The F_RDLCK, F_WRLCK, and F_UNLCK constants. - (compile-time-value - (cond ((string-contains %host-type "sparc") #(1 2 3)) ; sparc-*-linux-gnu - ((string-contains %host-type "hppa") #(1 2 3)) ; hppa-*-linux-gnu - ((string-contains %host-type "linux") #(0 1 2)) ; *-linux-gnu - (else #(1 2 3))))) ; *-gnu* - -(define fcntl-flock - (let* ((ptr (dynamic-func "fcntl" (dynamic-link))) - (proc (pointer->procedure int ptr `(,int ,int *)))) - (lambda* (fd-or-port operation #:key (wait? #t)) - "Perform locking OPERATION on the file beneath FD-OR-PORT. OPERATION -must be a symbol, one of 'read-lock, 'write-lock, or 'unlock. When WAIT? is -true, block until the lock is acquired; otherwise, thrown an 'flock-error' -exception if it's already taken." - (define (operation->int op) - (case op - ((read-lock) (vector-ref F_xxLCK 0)) - ((write-lock) (vector-ref F_xxLCK 1)) - ((unlock) (vector-ref F_xxLCK 2)) - (else (error "invalid fcntl-flock operation" op)))) - - (define fd - (if (port? fd-or-port) - (fileno fd-or-port) - fd-or-port)) - - ;; XXX: 'fcntl' is a vararg function, but here we happily use the - ;; standard ABI; crossing fingers. - (let ((err (proc fd - (if wait? - F_SETLKW ; lock & wait - F_SETLK) ; non-blocking attempt - (make-c-struct %struct-flock - (list (operation->int operation) - SEEK_SET - 0 0 ; whole file - 0))))) - (or (zero? err) - - ;; Presumably we got EAGAIN or so. - (throw 'flock-error (errno))))))) - - -;;; -;;; Miscellaneous. +;;; Keyword arguments. ;;; -(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 (strip-keyword-arguments keywords args) "Remove all of the keyword arguments listed in KEYWORDS from ARGS." (let loop ((args args) @@ -534,6 +428,11 @@ For instance: (#f (loop rest kw/values (cons* value kw result)))))))) + +;;; +;;; System strings. +;;; + (define* (nix-system->gnu-triplet #:optional (system (%current-system)) (vendor "unknown")) "Return a guess of the GNU triplet corresponding to Nix system @@ -732,79 +631,6 @@ output port, and PROC's result is returned." (lambda (key . args) (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))))))))) - -(define (fold-tree proc init children roots) - "Call (PROC NODE RESULT) for each node in the tree that is reachable from -ROOTS, using INIT as the initial value of RESULT. The order in which nodes -are traversed is not specified, however, each node is visited only once, based -on an eq? check. Children of a node to be visited are generated by -calling (CHILDREN NODE), the result of which should be a list of nodes that -are connected to NODE in the tree, or '() or #f if NODE is a leaf node." - (let loop ((result init) - (seen vlist-null) - (lst roots)) - (match lst - (() result) - ((head . tail) - (if (not (vhash-assq head seen)) - (loop (proc head result) - (vhash-consq head #t seen) - (match (children head) - ((or () #f) tail) - (children (append tail children)))) - (loop result seen tail)))))) - -(define (fold-tree-leaves proc init children roots) - "Like fold-tree, but call (PROC NODE RESULT) only for leaf nodes." - (fold-tree - (lambda (node result) - (match (children node) - ((or () #f) (proc node result)) - (else result))) - init children roots)) - -(define (split lst e) - "Return two values, a list containing the elements of the list LST that -appear before the first occurence of the object E and a list containing the -elements after E." - (define (same? x) - (equal? e x)) - - (let loop ((rest lst) - (acc '())) - (match rest - (() - (values lst '())) - (((? same?) . tail) - (values (reverse acc) tail)) - ((head . tail) - (loop tail (cons head acc)))))) - (define (cache-directory) "Return the cache directory for Guix, by default ~/.cache/guix." (or (getenv "XDG_CONFIG_HOME") |