Add (guix progress).

Among other things, this removes (guix utils), (guix ui), (guix config),
etc. from the closure of (guix build download), as was the case since
798648515b77507c242752457b4dc17c155bad6e.

* guix/utils.scm (<progress-reporter>, call-with-progress-reporter):
Move to...
* guix/progress.scm: ... here.  New file.
* Makefile.am (MODULES): Add it.
* guix/build/download.scm (current-terminal-columns)
(nearest-exact-integer, duration->seconds, seconds->string)
(byte-count->string, progress-bar, string-pad-middle)
(rate-limited, progress-reporter/file, dump-port*)
(time-monotonic): Move to progress.scm.
* guix/scripts/download.scm: Adjust accordingly.
* guix/scripts/substitute.scm: Likewise.

6 files changed, 236 insertions, 197 deletions

diff --git a/Makefile.am b/Makefile.am
index efbd07a351..071553b997 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -47,6 +47,7 @@ MODULES =					\
   guix/hash.scm					\
   guix/pk-crypto.scm				\
   guix/pki.scm					\
+  guix/progress.scm				\
   guix/combinators.scm				\
   guix/memoization.scm				\
   guix/utils.scm				\
diff --git a/guix/build/download.scm b/guix/build/download.scm
index 3b89f9412f..61c9c6d3f1 100644
--- a/guix/build/download.scm
+++ b/guix/build/download.scm
@@ -1,7 +1,6 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2015 Mark H Weaver <mhw@netris.org>
-;;; Copyright © 2015 Steve Sprang <scs@stevesprang.com>
 ;;; Copyright © 2017 Tobias Geerinckx-Rice <me@tobias.gr>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -27,7 +26,7 @@
   #:use-module (guix base64)
   #:use-module (guix ftp-client)
   #:use-module (guix build utils)
-  #:use-module (guix utils)
+  #:use-module (guix progress)
   #:use-module (rnrs io ports)
   #:use-module (rnrs bytevectors)
   #:use-module (srfi srfi-1)
@@ -46,8 +45,6 @@
             maybe-expand-mirrors
             url-fetch
             byte-count->string
-            current-terminal-columns
-            progress-reporter/file
             uri-abbreviation
             nar-uri-abbreviation
             store-path-abbreviation))
@@ -62,69 +59,6 @@
   ;; Size of the HTTP receive buffer.
   65536)
 
-(define current-terminal-columns
-  ;; Number of columns of the terminal.
-  (make-parameter 80))
-
-(define (nearest-exact-integer x)
-  "Given a real number X, return the nearest exact integer, with ties going to
-the nearest exact even integer."
-  (inexact->exact (round x)))
-
-(define (duration->seconds duration)
-  "Return the number of seconds represented by DURATION, a 'time-duration'
-object, as an inexact number."
-  (+ (time-second duration)
-     (/ (time-nanosecond duration) 1e9)))
-
-(define (seconds->string duration)
-  "Given DURATION in seconds, return a string representing it in 'mm:ss' or
-'hh:mm:ss' format, as needed."
-  (if (not (number? duration))
-      "00:00"
-      (let* ((total-seconds (nearest-exact-integer duration))
-             (extra-seconds (modulo total-seconds 3600))
-             (num-hours     (quotient total-seconds 3600))
-             (hours         (and (positive? num-hours) num-hours))
-             (mins          (quotient extra-seconds 60))
-             (secs          (modulo extra-seconds 60)))
-        (format #f "~@[~2,'0d:~]~2,'0d:~2,'0d" hours mins secs))))
-
-(define (byte-count->string size)
-  "Given SIZE in bytes, return a string representing it in a human-readable
-way."
-  (let ((KiB 1024.)
-        (MiB (expt 1024. 2))
-        (GiB (expt 1024. 3))
-        (TiB (expt 1024. 4)))
-    (cond
-     ((< size KiB) (format #f "~dB"     (nearest-exact-integer size)))
-     ((< size MiB) (format #f "~dKiB"   (nearest-exact-integer (/ size KiB))))
-     ((< size GiB) (format #f "~,1fMiB" (/ size MiB)))
-     ((< size TiB) (format #f "~,2fGiB" (/ size GiB)))
-     (else         (format #f "~,3fTiB" (/ size TiB))))))
-
-(define* (progress-bar % #:optional (bar-width 20))
-  "Return % as a string representing an ASCII-art progress bar.  The total
-width of the bar is BAR-WIDTH."
-  (let* ((fraction (/ % 100))
-         (filled   (inexact->exact (floor (* fraction bar-width))))
-         (empty    (- bar-width filled)))
-    (format #f "[~a~a]"
-            (make-string filled #\#)
-            (make-string empty #\space))))
-
-(define (string-pad-middle left right len)
-  "Combine LEFT and RIGHT with enough padding in the middle so that the
-resulting string has length at least LEN (it may overflow).  If the string
-does not overflow, the last char in RIGHT will be flush with the LEN
-column."
-  (let* ((total-used (+ (string-length left)
-                        (string-length right)))
-         (num-spaces (max 1 (- len total-used)))
-         (padding    (make-string num-spaces #\space)))
-    (string-append left padding right)))
-
 (define* (ellipsis #:optional (port (current-output-port)))
   "Make a rough guess at whether Unicode's HORIZONTAL ELLIPSIS can be written
 in PORT's encoding, and return either that or ASCII dots."
@@ -143,105 +77,6 @@ Otherwise return STORE-PATH."
                        (string-drop base 32)))
       store-path))
 
-(cond-expand
-  (guile-2.2
-   ;; Guile 2.2.2 has a bug whereby 'time-monotonic' objects have seconds and
-   ;; nanoseconds swapped (fixed in Guile commit 886ac3e).  Work around it.
-   (define time-monotonic time-tai))
-  (else #t))
-
-
-;; TODO: replace '(@ (guix build utils) dump-port))'.
-(define* (dump-port* in out
-                     #:key (buffer-size 16384)
-                     (reporter (make-progress-reporter noop noop noop)))
-  "Read as much data as possible from IN and write it to OUT, using chunks of
-BUFFER-SIZE bytes.  After each successful transfer of BUFFER-SIZE bytes or
-less, report the total number of bytes transferred to the REPORTER, which
-should be a <progress-reporter> object."
-  (define buffer
-    (make-bytevector buffer-size))
-
-  (call-with-progress-reporter reporter
-    (lambda (report)
-      (let loop ((total 0)
-                 (bytes (get-bytevector-n! in buffer 0 buffer-size)))
-        (or (eof-object? bytes)
-            (let ((total (+ total bytes)))
-              (put-bytevector out buffer 0 bytes)
-              (report total)
-              (loop total (get-bytevector-n! in buffer 0 buffer-size))))))))
-
-(define (rate-limited proc interval)
-  "Return a procedure that will forward the invocation to PROC when the time
-elapsed since the previous forwarded invocation is greater or equal to
-INTERVAL (a time-duration object), otherwise does nothing and returns #f."
-  (let ((previous-at #f))
-    (lambda args
-      (let* ((now (current-time time-monotonic))
-             (forward-invocation (lambda ()
-                                   (set! previous-at now)
-                                   (apply proc args))))
-        (if previous-at
-            (let ((elapsed (time-difference now previous-at)))
-              (if (time>=? elapsed interval)
-                  (forward-invocation)
-                  #f))
-            (forward-invocation))))))
-
-(define* (progress-reporter/file file size
-                                 #:optional (log-port (current-output-port))
-                                 #:key (abbreviation basename))
-  "Return a <progress-reporter> object to show the progress of FILE's download,
-which is SIZE bytes long.  The progress report is written to LOG-PORT, with
-ABBREVIATION used to shorten FILE for display."
-  (let ((start-time (current-time time-monotonic))
-        (transferred 0))
-    (define (render)
-      "Write the progress report to LOG-PORT."
-      (define elapsed
-        (duration->seconds
-         (time-difference (current-time time-monotonic) start-time)))
-      (if (number? size)
-          (let* ((%  (* 100.0 (/ transferred size)))
-                 (throughput (/ transferred elapsed))
-                 (left       (format #f " ~a  ~a"
-                                     (abbreviation file)
-                                     (byte-count->string size)))
-                 (right      (format #f "~a/s ~a ~a~6,1f%"
-                                     (byte-count->string throughput)
-                                     (seconds->string elapsed)
-                                     (progress-bar %) %)))
-            (display "\r\x1b[K" log-port)
-            (display (string-pad-middle left right
-                                        (current-terminal-columns))
-                     log-port)
-            (flush-output-port log-port))
-          (let* ((throughput (/ transferred elapsed))
-                 (left       (format #f " ~a"
-                                     (abbreviation file)))
-                 (right      (format #f "~a/s ~a | ~a transferred"
-                                     (byte-count->string throughput)
-                                     (seconds->string elapsed)
-                                     (byte-count->string transferred))))
-            (display "\r\x1b[K" log-port)
-            (display (string-pad-middle left right
-                                        (current-terminal-columns))
-                     log-port)
-            (flush-output-port log-port))))
-
-    (progress-reporter
-     (start render)
-     ;; Report the progress every 300ms or longer.
-     (report
-      (let ((rate-limited-render
-             (rate-limited render (make-time time-monotonic 300000000 0))))
-        (lambda (value)
-          (set! transferred value)
-          (rate-limited-render))))
-     ;; Don't miss the last report.
-     (stop render))))
-
 (define* (uri-abbreviation uri #:optional (max-length 42))
   "If URI's string representation is larger than MAX-LENGTH, return an
 abbreviation of URI showing the scheme, host, and basename of the file."
diff --git a/guix/progress.scm b/guix/progress.scm
new file mode 100644
index 0000000000..beca2c22a6
--- /dev/null
+++ b/guix/progress.scm
@@ -0,0 +1,228 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2017 Sou Bunnbu <iyzsong@gmail.com>
+;;; Copyright © 2015 Steve Sprang <scs@stevesprang.com>
+;;;
+;;; 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 progress)
+  #:use-module (guix records)
+  #:use-module (srfi srfi-19)
+  #:use-module (rnrs io ports)
+  #:use-module (rnrs bytevectors)
+  #:use-module (ice-9 format)
+  #:use-module (ice-9 match)
+  #:export (<progress-reporter>
+            progress-reporter
+            make-progress-reporter
+            progress-reporter?
+            call-with-progress-reporter
+
+            progress-reporter/silent
+            progress-reporter/file
+
+            byte-count->string
+            current-terminal-columns
+
+            dump-port*))
+
+;;; Commentary:
+;;;
+;;; Helper to write progress report code for downloads, etc.
+;;;
+;;; Code:
+
+(define-record-type* <progress-reporter>
+  progress-reporter make-progress-reporter progress-reporter?
+  (start   progress-reporter-start)     ; thunk
+  (report  progress-reporter-report)    ; procedure
+  (stop    progress-reporter-stop))     ; thunk
+
+(define (call-with-progress-reporter reporter proc)
+  "Start REPORTER for progress reporting, and call @code{(@var{proc} report)}
+with the resulting report procedure.  When @var{proc} returns, the REPORTER is
+stopped."
+  (match reporter
+    (($ <progress-reporter> start report stop)
+     (dynamic-wind start (lambda () (proc report)) stop))))
+
+(define progress-reporter/silent
+  (make-progress-reporter noop noop noop))
+
+
+;;;
+;;; File download progress report.
+;;;
+
+(cond-expand
+  (guile-2.2
+   ;; Guile 2.2.2 has a bug whereby 'time-monotonic' objects have seconds and
+   ;; nanoseconds swapped (fixed in Guile commit 886ac3e).  Work around it.
+   (define time-monotonic time-tai))
+  (else #t))
+
+(define (nearest-exact-integer x)
+  "Given a real number X, return the nearest exact integer, with ties going to
+the nearest exact even integer."
+  (inexact->exact (round x)))
+
+(define (duration->seconds duration)
+  "Return the number of seconds represented by DURATION, a 'time-duration'
+object, as an inexact number."
+  (+ (time-second duration)
+     (/ (time-nanosecond duration) 1e9)))
+
+(define (seconds->string duration)
+  "Given DURATION in seconds, return a string representing it in 'mm:ss' or
+'hh:mm:ss' format, as needed."
+  (if (not (number? duration))
+      "00:00"
+      (let* ((total-seconds (nearest-exact-integer duration))
+             (extra-seconds (modulo total-seconds 3600))
+             (num-hours     (quotient total-seconds 3600))
+             (hours         (and (positive? num-hours) num-hours))
+             (mins          (quotient extra-seconds 60))
+             (secs          (modulo extra-seconds 60)))
+        (format #f "~@[~2,'0d:~]~2,'0d:~2,'0d" hours mins secs))))
+
+(define (byte-count->string size)
+  "Given SIZE in bytes, return a string representing it in a human-readable
+way."
+  (let ((KiB 1024.)
+        (MiB (expt 1024. 2))
+        (GiB (expt 1024. 3))
+        (TiB (expt 1024. 4)))
+    (cond
+     ((< size KiB) (format #f "~dB"     (nearest-exact-integer size)))
+     ((< size MiB) (format #f "~dKiB"   (nearest-exact-integer (/ size KiB))))
+     ((< size GiB) (format #f "~,1fMiB" (/ size MiB)))
+     ((< size TiB) (format #f "~,2fGiB" (/ size GiB)))
+     (else         (format #f "~,3fTiB" (/ size TiB))))))
+
+(define (string-pad-middle left right len)
+  "Combine LEFT and RIGHT with enough padding in the middle so that the
+resulting string has length at least LEN (it may overflow).  If the string
+does not overflow, the last char in RIGHT will be flush with the LEN
+column."
+  (let* ((total-used (+ (string-length left)
+                        (string-length right)))
+         (num-spaces (max 1 (- len total-used)))
+         (padding    (make-string num-spaces #\space)))
+    (string-append left padding right)))
+
+(define (rate-limited proc interval)
+  "Return a procedure that will forward the invocation to PROC when the time
+elapsed since the previous forwarded invocation is greater or equal to
+INTERVAL (a time-duration object), otherwise does nothing and returns #f."
+  (let ((previous-at #f))
+    (lambda args
+      (let* ((now (current-time time-monotonic))
+             (forward-invocation (lambda ()
+                                   (set! previous-at now)
+                                   (apply proc args))))
+        (if previous-at
+            (let ((elapsed (time-difference now previous-at)))
+              (if (time>=? elapsed interval)
+                  (forward-invocation)
+                  #f))
+            (forward-invocation))))))
+
+(define current-terminal-columns
+  ;; Number of columns of the terminal.
+  (make-parameter 80))
+
+(define* (progress-bar % #:optional (bar-width 20))
+  "Return % as a string representing an ASCII-art progress bar.  The total
+width of the bar is BAR-WIDTH."
+  (let* ((fraction (/ % 100))
+         (filled   (inexact->exact (floor (* fraction bar-width))))
+         (empty    (- bar-width filled)))
+    (format #f "[~a~a]"
+            (make-string filled #\#)
+            (make-string empty #\space))))
+
+(define* (progress-reporter/file file size
+                                 #:optional (log-port (current-output-port))
+                                 #:key (abbreviation basename))
+  "Return a <progress-reporter> object to show the progress of FILE's download,
+which is SIZE bytes long.  The progress report is written to LOG-PORT, with
+ABBREVIATION used to shorten FILE for display."
+  (let ((start-time (current-time time-monotonic))
+        (transferred 0))
+    (define (render)
+      "Write the progress report to LOG-PORT."
+      (define elapsed
+        (duration->seconds
+         (time-difference (current-time time-monotonic) start-time)))
+      (if (number? size)
+          (let* ((%  (* 100.0 (/ transferred size)))
+                 (throughput (/ transferred elapsed))
+                 (left       (format #f " ~a  ~a"
+                                     (abbreviation file)
+                                     (byte-count->string size)))
+                 (right      (format #f "~a/s ~a ~a~6,1f%"
+                                     (byte-count->string throughput)
+                                     (seconds->string elapsed)
+                                     (progress-bar %) %)))
+            (display "\r\x1b[K" log-port)
+            (display (string-pad-middle left right
+                                        (current-terminal-columns))
+                     log-port)
+            (force-output log-port))
+          (let* ((throughput (/ transferred elapsed))
+                 (left       (format #f " ~a"
+                                     (abbreviation file)))
+                 (right      (format #f "~a/s ~a | ~a transferred"
+                                     (byte-count->string throughput)
+                                     (seconds->string elapsed)
+                                     (byte-count->string transferred))))
+            (display "\r\x1b[K" log-port)
+            (display (string-pad-middle left right
+                                        (current-terminal-columns))
+                     log-port)
+            (force-output log-port))))
+
+    (progress-reporter
+     (start render)
+     ;; Report the progress every 300ms or longer.
+     (report
+      (let ((rate-limited-render
+             (rate-limited render (make-time time-monotonic 300000000 0))))
+        (lambda (value)
+          (set! transferred value)
+          (rate-limited-render))))
+     ;; Don't miss the last report.
+     (stop render))))
+
+;; TODO: replace '(@ (guix build utils) dump-port))'.
+(define* (dump-port* in out
+                     #:key (buffer-size 16384)
+                     (reporter progress-reporter/silent))
+  "Read as much data as possible from IN and write it to OUT, using chunks of
+BUFFER-SIZE bytes.  After each successful transfer of BUFFER-SIZE bytes or
+less, report the total number of bytes transferred to the REPORTER, which
+should be a <progress-reporter> object."
+  (define buffer
+    (make-bytevector buffer-size))
+
+  (call-with-progress-reporter reporter
+    (lambda (report)
+      (let loop ((total 0)
+                 (bytes (get-bytevector-n! in buffer 0 buffer-size)))
+        (or (eof-object? bytes)
+            (let ((total (+ total bytes)))
+              (put-bytevector out buffer 0 bytes)
+              (report total)
+              (loop total (get-bytevector-n! in buffer 0 buffer-size))))))))
diff --git a/guix/scripts/download.scm b/guix/scripts/download.scm
index 8225f82bb9..1b99bc62cf 100644
--- a/guix/scripts/download.scm
+++ b/guix/scripts/download.scm
@@ -25,7 +25,9 @@
   #:use-module (guix base32)
   #:use-module ((guix download) #:hide (url-fetch))
   #:use-module ((guix build download)
-                #:select (url-fetch current-terminal-columns))
+                #:select (url-fetch))
+  #:use-module ((guix progress)
+                #:select (current-terminal-columns))
   #:use-module ((guix build syscalls)
                 #:select (terminal-columns))
   #:use-module (web uri)
diff --git a/guix/scripts/substitute.scm b/guix/scripts/substitute.scm
index 60dbdb1766..1fbeed71e8 100755
--- a/guix/scripts/substitute.scm
+++ b/guix/scripts/substitute.scm
@@ -33,13 +33,12 @@
   #:use-module (guix pki)
   #:use-module ((guix build utils) #:select (mkdir-p dump-port))
   #:use-module ((guix build download)
-                #:select (current-terminal-columns
-                          progress-reporter/file
-                          uri-abbreviation nar-uri-abbreviation
+                #:select (uri-abbreviation nar-uri-abbreviation
                           (open-connection-for-uri
                            . guix:open-connection-for-uri)
                           close-connection
                           store-path-abbreviation byte-count->string))
+  #:use-module (guix progress)
   #:use-module ((guix build syscalls)
                 #:select (set-thread-name))
   #:use-module (ice-9 rdelim)
diff --git a/guix/utils.scm b/guix/utils.scm
index 2cf9be36df..eb1ec29b32 100644
--- a/guix/utils.scm
+++ b/guix/utils.scm
@@ -33,7 +33,6 @@
   #:autoload   (rnrs io ports) (make-custom-binary-input-port)
   #:use-module ((rnrs bytevectors) #:select (bytevector-u8-set!))
   #:use-module (guix memoization)
-  #:use-module (guix records)
   #:use-module ((guix build utils) #:select (dump-port mkdir-p))
   #:use-module ((guix build syscalls) #:select (mkdtemp! fdatasync))
   #:use-module (ice-9 format)
@@ -95,13 +94,7 @@
             call-with-decompressed-port
             compressed-output-port
             call-with-compressed-output-port
-            canonical-newline-port
-
-            <progress-reporter>
-            progress-reporter
-            make-progress-reporter
-            progress-reporter?
-            call-with-progress-reporter))
+            canonical-newline-port))
 
 
 ;;;
@@ -757,25 +750,6 @@ a location object."
     (column   . ,(location-column loc))
     (filename . ,(location-file loc))))
 
-
-;;;
-;;; Progress reporter.
-;;;
-
-(define-record-type* <progress-reporter>
-  progress-reporter make-progress-reporter progress-reporter?
-  (start   progress-reporter-start)     ; thunk
-  (report  progress-reporter-report)    ; procedure
-  (stop    progress-reporter-stop))     ; thunk
-
-(define (call-with-progress-reporter reporter proc)
-  "Start REPORTER for progress reporting, and call @code{(@var{proc} report)}
-with the resulting report procedure.  When @var{proc} returns, the REPORTER is
-stopped."
-  (match reporter
-    (($ <progress-reporter> start report stop)
-     (dynamic-wind start (lambda () (proc report)) stop))))
-
 ;;; Local Variables:
 ;;; eval: (put 'call-with-progress-reporter 'scheme-indent-function 1)
 ;;; End: