[vte] regex: Pass more data to regex matching

[Christian Persch <chpe src gnome org>]

commit 93bfe531e986fde14f7588ba546ad244767e2be1
Author: Christian Persch <chpe gnome org>
Date:   Wed Oct 7 22:15:05 2015 +0200

    regex: Pass more data to regex matching
    
    Pass the whole match contents before the line to matching, which is useful
    if there are lookbehind assertions in the regex. We also want to pass
    the whole contents after the line to matching to satisfy lookahead
    assertions, but this isn't possible currently without new PCRE2 API.
    
    This also fixes the cell row/column info in the debug output.

 src/vte.cc |   42 ++++++++++++++++++++++--------------------
 1 files changed, 22 insertions(+), 20 deletions(-)
---
diff --git a/src/vte.cc b/src/vte.cc
index a48b1d9..5e9562a 100644
--- a/src/vte.cc
+++ b/src/vte.cc
@@ -1583,8 +1583,6 @@ match_rowcol_to_offset(VteTerminal *terminal,
                /* nothing to match on this line */
                return FALSE;
        }
-       offset -= sattr;
-       eattr -= sattr;
 
         *offset_ptr = offset;
         *sattr_ptr = sattr;
@@ -1632,14 +1630,18 @@ vte_terminal_match_check_internal_pcre(VteTerminal *terminal,
 
         /* Identical with vte_terminal_match_check_internal_gregex until END */
 
-        if (!match_rowcol_to_offset(terminal, column,row,
+        if (!match_rowcol_to_offset(terminal, column, row,
                                     &offset, &sattr, &eattr))
                 return NULL;
 
-       line = terminal->pvt->match_contents + sattr;
+       line = terminal->pvt->match_contents;
+        /* FIXME: what we really want is to pass the whole data to pcre2_match, but
+         * limit matching to between sattr and eattr, so that the extra data can
+         * satisfy lookahead assertions. This needs new pcre2 API though.
+         */
         line_length = eattr;
 
-       start_blank = 0;
+       start_blank = sattr;
        end_blank = eattr;
 
         //        _vte_debug_print(VTE_DEBUG_REGEX, "Cursor offset: %" G_GSSIZE_FORMAT " in line with length 
%" G_GSSIZE_FORMAT "): %*s\n",
@@ -1676,10 +1678,10 @@ vte_terminal_match_check_internal_pcre(VteTerminal *terminal,
                 * matches, so we'll have to skip each match until we
                 * stop getting matches. */
 
-                position = 0;
-                while (position < line_length &&
+                position = sattr;
+                while (position < eattr &&
                        ((r = match_fn(vte_regex_get_pcre(regex->regex.pcre.regex),
-                                      (PCRE2_SPTR8)line, line_length , /* subject, length */
+                                      (PCRE2_SPTR8)line, line_length, /* subject, length */
                                       position, /* start offset */
                                       regex->regex.pcre.match_flags |
                                       PCRE2_NO_UTF_CHECK | PCRE2_NOTEMPTY | PCRE2_PARTIAL_SOFT /* FIXME: 
HARD? */,
@@ -1739,10 +1741,10 @@ vte_terminal_match_check_internal_pcre(VteTerminal *terminal,
                                         *tag = regex->tag;
                                 }
                                 if (start != NULL) {
-                                        *start = sattr + rm_so;
+                                        *start = rm_so;
                                 }
                                 if (end != NULL) {
-                                        *end = sattr + rm_eo - 1;
+                                        *end = rm_eo - 1;
                                 }
 
                                 result = g_strndup(line + rm_so, rm_eo - rm_so);
@@ -1779,10 +1781,10 @@ vte_terminal_match_check_internal_pcre(VteTerminal *terminal,
 
         // FIXME: WTF is this doing and why?
        if (start != NULL) {
-               *start = sattr + start_blank;
+               *start = start_blank;
        }
        if (end != NULL) {
-               *end = sattr + end_blank - 1;
+               *end = end_blank - 1;
        }
        return NULL;
 }
@@ -1806,15 +1808,15 @@ vte_terminal_match_check_internal_gregex(VteTerminal *terminal,
 
         /* Identical with vte_terminal_match_check_internal_pcre until END */
 
-        if (!match_rowcol_to_offset(terminal, column,row,
+        if (!match_rowcol_to_offset(terminal, column, row,
                                     &offset, &sattr, &eattr))
                 return NULL;
 
        /* temporarily shorten the contents to this row */
-       line = terminal->pvt->match_contents + sattr;
+       line = terminal->pvt->match_contents;
         line_length = eattr;
 
-       start_blank = 0;
+       start_blank = sattr;
        end_blank = eattr;
 
         //        _vte_debug_print(VTE_DEBUG_REGEX, "Cursor offset: %" G_GSSIZE_FORMAT " in line with length 
%" G_GSSIZE_FORMAT "): %*s\n",
@@ -1838,7 +1840,7 @@ vte_terminal_match_check_internal_gregex(VteTerminal *terminal,
                 * matches, so we'll have to skip each match until we
                 * stop getting matches. */
                 if (!g_regex_match_full(regex->regex.gregex.regex,
-                                        line, line_length, 0,
+                                        line, line_length, sattr,
                                         regex->regex.gregex.match_flags,
                                         &match_info,
                                         NULL)) {
@@ -1886,10 +1888,10 @@ vte_terminal_match_check_internal_gregex(VteTerminal *terminal,
                                                *tag = regex->tag;
                                        }
                                        if (start != NULL) {
-                                               *start = sattr + rm_so;
+                                               *start = rm_so;
                                        }
                                        if (end != NULL) {
-                                               *end = sattr + rm_eo - 1;
+                                               *end = rm_eo - 1;
                                        }
                                         vte_terminal_set_cursor_from_regex_match(terminal, regex);
                                         result = g_match_info_fetch(match_info, 0);
@@ -1920,10 +1922,10 @@ vte_terminal_match_check_internal_gregex(VteTerminal *terminal,
        }
 
        if (start != NULL) {
-               *start = sattr + start_blank;
+               *start = start_blank;
        }
        if (end != NULL) {
-               *end = sattr + end_blank - 1;
+               *end = end_blank - 1;
        }
        return NULL;
 }