revised and improved the Unicode glyph-to-byte conversion heuristics

Previously almost all glyph-to-byte offset conversions consulted
Scintilla's line index and counted characters on the resulting line.
For instance a simple expression like `.+1J` would scan the same line
twice completely, which would be very slow on pathologically long lines.
Even insertions did that due to having to update the ^Y ranges.
If you repeat such an operation over all characters as in `<.+1:J;>`
you would have complexity O(n^2) for n = line length.
Only commands with an explicit relative nature like `C` and `A` would
use teco_view_glyph2bytes_relative() which scans beginning at dot
as long as the relative movement is less than 1024 glyphs.

Wit the new heuristics almost all glyph-to-byte and byte-to-glyph
conversions can make use of that optimization.
This requires that dot must at all times be known in glyphs as well -
the byte position is managed by Scintilla (SCI_GETCURRENTPOS).
We therefore introduced teco_current_doc_set_dot() and
teco_current_doc_get_dot() to update dot in the current buffer or
Q-Register -- it cannot be stored along with the view since
Q-Registers share a single view.
A number of auxiliary functions have been introduced for
converting relative to a known (glyphs,bytes) offset pair
and for converting absolute and relative positions with regard
to the current doc and SCI_GETCURRENTPOS position.
Of course this is error-prone since the glyph and dot positions
are interdependant - they must always be kept in sync.

With these new optimizations even pathologically long lines can
(usually) be managed even in UTF-8 documents.
It does not address slow-downs in Scintilla's line layout, yet.
grosciteco.tes for instance runs twice as fast now.

1 files changed, 14 insertions, 7 deletions

diff --git a/src/glob.c b/src/glob.c
index 0917e5c..24f2647 100644
--- a/src/glob.c
+++ b/src/glob.c
@@ -38,6 +38,7 @@
 #include "expressions.h"
 #include "qreg.h"
 #include "ring.h"
+#include "view.h"
 #include "error.h"
 #include "undo.h"
 #include "glob.h"
@@ -527,21 +528,24 @@ teco_state_glob_filename_done(teco_machine_main_t *ctx, teco_string_t str, GErro
 		gint rc = tere_exec(&pattern, (chr *)filename, strlen(filename), NULL, 0, NULL, 0);
 		if (rc == REG_OKAY && (teco_test_mode == 0 || g_file_test(filename, file_flags))) {
 			if (!colon_modified) {
-				sptr_t pos = teco_interface_ssm(SCI_GETCURRENTPOS, 0, 0);
-
 				/*
 				 * FIXME: Filenames may contain linefeeds.
 				 * But if we add them null-terminated, they will be relatively hard to parse.
 				 */
 				gsize len = strlen(filename);
 				filename[len] = '\n';
+
+				sptr_t pos = teco_interface_ssm(SCI_GETCURRENTPOS, 0, 0);
+				teco_undo_int(teco_ranges[0].from) = teco_current_doc_get_dot();
+
 				teco_interface_ssm(SCI_BEGINUNDOACTION, 0, 0);
 				teco_interface_ssm(SCI_ADDTEXT, len+1, (sptr_t)filename);
 				teco_interface_ssm(SCI_ENDUNDOACTION, 0, 0);
 
-				teco_undo_int(teco_ranges[0].from) = teco_interface_bytes2glyphs(pos);
-				teco_undo_int(teco_ranges[0].to) = teco_interface_bytes2glyphs(pos + len + 1);
+				teco_int_t to = teco_interface_bytes2glyphs_rel(teco_ranges[0].from, pos, len + 1);
+				teco_undo_int(teco_ranges[0].to) = to;
 				teco_undo_guint(teco_ranges_count) = 1;
+				teco_current_doc_set_dot(to);
 			}
 
 			matching = TRUE;
@@ -565,14 +569,15 @@ teco_state_glob_filename_done(teco_machine_main_t *ctx, teco_string_t str, GErro
 		globber = teco_globber_new(pattern_str.data, file_flags);
 
 		sptr_t pos = teco_interface_ssm(SCI_GETCURRENTPOS, 0, 0);
-		teco_undo_int(teco_ranges[0].from) = teco_interface_bytes2glyphs(pos);
+		gsize total_len = 0;
+		teco_undo_int(teco_ranges[0].from) = teco_current_doc_get_dot();
 
 		teco_interface_ssm(SCI_BEGINUNDOACTION, 0, 0);
 
 		gchar *globbed_filename;
 		while ((globbed_filename = teco_globber_next(globber))) {
 			gsize len = strlen(globbed_filename);
-			pos += len+1;
+			total_len += len+1;
 
 			/*
 			 * FIXME: Filenames may contain linefeeds.
@@ -587,8 +592,10 @@ teco_state_glob_filename_done(teco_machine_main_t *ctx, teco_string_t str, GErro
 
 		teco_interface_ssm(SCI_ENDUNDOACTION, 0, 0);
 
-		teco_undo_int(teco_ranges[0].to) = teco_interface_bytes2glyphs(pos);
+		teco_int_t to = teco_interface_bytes2glyphs_rel(teco_ranges[0].from, pos, total_len);
+		teco_undo_int(teco_ranges[0].to) = to;
 		teco_undo_guint(teco_ranges_count) = 1;
+		teco_current_doc_set_dot(to);
 	}
 
 	if (colon_modified) {