builtin/apply: extract line_by_line_fuzzy_match() from match_fragment()

The match_fragment() function is very big and contains a big special case
algorithm that does line by line fuzzy matching. So let's extract this
algorithm in a separate line_by_line_fuzzy_match() function.

Reviewed-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Christian Couder 2016-05-11 15:16:16 +02:00 committed by Junio C Hamano
parent bb0ba99743
commit 7a3eb9e222

View file

@ -2242,6 +2242,74 @@ static void update_pre_post_images(struct image *preimage,
postimage->nr -= reduced;
}
static int line_by_line_fuzzy_match(struct image *img,
struct image *preimage,
struct image *postimage,
unsigned long try,
int try_lno,
int preimage_limit)
{
int i;
size_t imgoff = 0;
size_t preoff = 0;
size_t postlen = postimage->len;
size_t extra_chars;
char *buf;
char *preimage_eof;
char *preimage_end;
struct strbuf fixed;
char *fixed_buf;
size_t fixed_len;
for (i = 0; i < preimage_limit; i++) {
size_t prelen = preimage->line[i].len;
size_t imglen = img->line[try_lno+i].len;
if (!fuzzy_matchlines(img->buf + try + imgoff, imglen,
preimage->buf + preoff, prelen))
return 0;
if (preimage->line[i].flag & LINE_COMMON)
postlen += imglen - prelen;
imgoff += imglen;
preoff += prelen;
}
/*
* Ok, the preimage matches with whitespace fuzz.
*
* imgoff now holds the true length of the target that
* matches the preimage before the end of the file.
*
* Count the number of characters in the preimage that fall
* beyond the end of the file and make sure that all of them
* are whitespace characters. (This can only happen if
* we are removing blank lines at the end of the file.)
*/
buf = preimage_eof = preimage->buf + preoff;
for ( ; i < preimage->nr; i++)
preoff += preimage->line[i].len;
preimage_end = preimage->buf + preoff;
for ( ; buf < preimage_end; buf++)
if (!isspace(*buf))
return 0;
/*
* Update the preimage and the common postimage context
* lines to use the same whitespace as the target.
* If whitespace is missing in the target (i.e.
* if the preimage extends beyond the end of the file),
* use the whitespace from the preimage.
*/
extra_chars = preimage_end - preimage_eof;
strbuf_init(&fixed, imgoff + extra_chars);
strbuf_add(&fixed, img->buf + try, imgoff);
strbuf_add(&fixed, preimage_eof, extra_chars);
fixed_buf = strbuf_detach(&fixed, &fixed_len);
update_pre_post_images(preimage, postimage,
fixed_buf, fixed_len, postlen);
return 1;
}
static int match_fragment(struct image *img,
struct image *preimage,
struct image *postimage,
@ -2331,61 +2399,9 @@ static int match_fragment(struct image *img,
* fuzzy matching. We collect all the line length information because
* we need it to adjust whitespace if we match.
*/
if (ws_ignore_action == ignore_ws_change) {
size_t imgoff = 0;
size_t preoff = 0;
size_t postlen = postimage->len;
size_t extra_chars;
char *preimage_eof;
char *preimage_end;
for (i = 0; i < preimage_limit; i++) {
size_t prelen = preimage->line[i].len;
size_t imglen = img->line[try_lno+i].len;
if (!fuzzy_matchlines(img->buf + try + imgoff, imglen,
preimage->buf + preoff, prelen))
return 0;
if (preimage->line[i].flag & LINE_COMMON)
postlen += imglen - prelen;
imgoff += imglen;
preoff += prelen;
}
/*
* Ok, the preimage matches with whitespace fuzz.
*
* imgoff now holds the true length of the target that
* matches the preimage before the end of the file.
*
* Count the number of characters in the preimage that fall
* beyond the end of the file and make sure that all of them
* are whitespace characters. (This can only happen if
* we are removing blank lines at the end of the file.)
*/
buf = preimage_eof = preimage->buf + preoff;
for ( ; i < preimage->nr; i++)
preoff += preimage->line[i].len;
preimage_end = preimage->buf + preoff;
for ( ; buf < preimage_end; buf++)
if (!isspace(*buf))
return 0;
/*
* Update the preimage and the common postimage context
* lines to use the same whitespace as the target.
* If whitespace is missing in the target (i.e.
* if the preimage extends beyond the end of the file),
* use the whitespace from the preimage.
*/
extra_chars = preimage_end - preimage_eof;
strbuf_init(&fixed, imgoff + extra_chars);
strbuf_add(&fixed, img->buf + try, imgoff);
strbuf_add(&fixed, preimage_eof, extra_chars);
fixed_buf = strbuf_detach(&fixed, &fixed_len);
update_pre_post_images(preimage, postimage,
fixed_buf, fixed_len, postlen);
return 1;
}
if (ws_ignore_action == ignore_ws_change)
return line_by_line_fuzzy_match(img, preimage, postimage,
try, try_lno, preimage_limit);
if (ws_error_action != correct_ws_error)
return 0;