@@ -34,6 +34,7 @@
#:use-module (srfi srfi-11)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-39)
+ #:use-module (srfi srfi-71)
#:use-module (ice-9 ftw)
#:use-module (rnrs io ports) ;need 'port-position' etc.
#:use-module ((rnrs bytevectors) #:select (bytevector-u8-set!))
@@ -344,14 +345,20 @@ a list of command-line arguments passed to the compression program."
;; 'go-to-location'.
(make-hash-table))
-(define (go-to-location port line column)
+(define (source-location-key/stamp stat)
+ "Return two values: the key for STAT in %SOURCE-LOCATION-MAP, and a stamp
+used to invalidate corresponding entries."
+ (let ((key (list (stat:ino stat) (stat:dev stat)))
+ (stamp (list (stat:mtime stat) (stat:mtimensec stat)
+ (stat:size stat))))
+ (values key stamp)))
+
+(define* (go-to-location port line column)
"Jump to LINE and COLUMN (both one-indexed) in PORT. Maintain a source
location map such that this can boil down to seek(2) and a few read(2) calls,
which can drastically speed up repetitive operations on large files."
(let* ((stat (stat port))
- (key (list (stat:ino stat) (stat:dev stat)))
- (stamp (list (stat:mtime stat) (stat:mtimensec stat)
- (stat:size stat)))
+ (key stamp (source-location-key/stamp stat))
;; Look for an up-to-date source map for KEY. The map is a vlist
;; where each entry gives the byte offset of the beginning of a line:
@@ -398,6 +405,20 @@ which can drastically speed up repetitive operations on large files."
(set-port-line! port (- line 1))
(set-port-column! port (- column 1))))
+(define (move-source-location-map! source target line)
+ "Move the source location map from SOURCE up to LINE to TARGET. SOURCE and
+TARGET must be stat buffers as returned by 'stat'."
+ (let* ((source-key (source-location-key/stamp source))
+ (target-key target-stamp (source-location-key/stamp target)))
+ (match (hash-ref %source-location-map source-key)
+ (#f #t)
+ ((_ ... source-map)
+ ;; Strip the source map and update the associated stamp.
+ (let ((source-map (vlist-take source-map (max line 1))))
+ (hash-remove! %source-location-map source-key)
+ (hash-set! %source-location-map target-key
+ `(,@target-stamp ,source-map)))))))
+
(define* (edit-expression source-properties proc #:key (encoding "UTF-8"))
"Edit the expression specified by SOURCE-PROPERTIES using PROC, which should
be a procedure that takes the original expression in string and returns a new
@@ -435,7 +456,13 @@ This procedure returns #t on success."
;; post-bv maybe the end-of-file object.
(when (not (eof-object? post-bv))
(put-bytevector out post-bv))
- #t)))))))))
+ #t))
+
+ ;; Due to 'with-atomic-file-output', IN and FILE no longer share
+ ;; the same inode, but we can reassign the source map up to LINE
+ ;; to the new file.
+ (move-source-location-map! (stat in) (stat file)
+ (+ 1 line)))))))))
;;;