vis: implement nn%

Moves to the given percentage of the file in bytes (not lines).

This is useful when dealing with huge files because it is a constant
time operation. Performance could still be improved by adapting the
display code not to rely on line numbers at all.

4 files changed, 25 insertions, 6 deletions

diff --git a/config.def.h b/config.def.h
index 30e17bb..47ed326 100644
--- a/config.def.h
+++ b/config.def.h
@@ -39,7 +39,7 @@ static const KeyBinding bindings_motions[] = {
 	{ "^",                  ACTION(CURSOR_LINE_START)                   },
 	{ "g_",                 ACTION(CURSOR_LINE_FINISH)                  },
 	{ "$",                  ACTION(CURSOR_LINE_LASTCHAR)                },
-	{ "%",                  ACTION(CURSOR_BRACKET_MATCH)                },
+	{ "%",                  ACTION(CURSOR_PERCENT)                      },
 	{ "b",                  ACTION(CURSOR_WORD_START_PREV)              },
 	{ "B",                  ACTION(CURSOR_LONGWORD_START_PREV)          },
 	{ "w",                  ACTION(CURSOR_WORD_START_NEXT)              },
diff --git a/main.c b/main.c
index f9fea56..dab27ea 100644
--- a/main.c
+++ b/main.c
@@ -107,6 +107,8 @@ static const char *call(Vis*, const char *keys, const Arg *arg);
 static const char *window(Vis*, const char *keys, const Arg *arg);
 /* show info about Unicode character at cursor position */
 static const char *unicode_info(Vis*, const char *keys, const Arg *arg);
+/* either go to count % of ile or to matching item */
+static const char *percent(Vis*, const char *keys, const Arg *arg);
 
 enum {
 	VIS_ACTION_EDITOR_SUSPEND,
@@ -132,7 +134,7 @@ enum {
 	VIS_ACTION_CURSOR_SCREEN_LINE_BEGIN,
 	VIS_ACTION_CURSOR_SCREEN_LINE_MIDDLE,
 	VIS_ACTION_CURSOR_SCREEN_LINE_END,
-	VIS_ACTION_CURSOR_BRACKET_MATCH,
+	VIS_ACTION_CURSOR_PERCENT,
 	VIS_ACTION_CURSOR_PARAGRAPH_PREV,
 	VIS_ACTION_CURSOR_PARAGRAPH_NEXT,
 	VIS_ACTION_CURSOR_SENTENCE_PREV,
@@ -385,10 +387,10 @@ static KeyAction vis_action[] = {
 		"Move cursor to end of screen/display line",
 		movement, { .i = VIS_MOVE_SCREEN_LINE_END }
 	},
-	[VIS_ACTION_CURSOR_BRACKET_MATCH] = {
-		"cursor-match-bracket",
-		"Match corresponding symbol if cursor is on a bracket character",
-		movement, { .i = VIS_MOVE_BRACKET_MATCH }
+	[VIS_ACTION_CURSOR_PERCENT] = {
+		"cursor-percent",
+		"Move to count % of file or matching item",
+		percent
 	},
 	[VIS_ACTION_CURSOR_PARAGRAPH_PREV] = {
 		"cursor-paragraph-prev",
@@ -1602,6 +1604,14 @@ static const char *unicode_info(Vis *vis, const char *keys, const Arg *arg) {
 	return keys;
 }
 
+static const char *percent(Vis *vis, const char *keys, const Arg *arg) {
+	if (vis_count_get(vis) == VIS_COUNT_UNKNOWN)
+		vis_motion(vis, VIS_MOVE_BRACKET_MATCH);
+	else
+		vis_motion(vis, VIS_MOVE_PERCENT);
+	return keys;
+}
+
 static Vis *vis;
 
 static void signal_handler(int signum, siginfo_t *siginfo, void *context) {
diff --git a/vis-motions.c b/vis-motions.c
index 3278546..91224b5 100644
--- a/vis-motions.c
+++ b/vis-motions.c
@@ -194,6 +194,13 @@ static size_t bracket_match(Text *txt, size_t pos) {
 	return pos;
 }
 
+static size_t percent(Vis *vis, Text *txt, size_t pos) {
+	int ratio = vis_count_get_default(vis, 0);
+	if (ratio > 100)
+		ratio = 100;
+	return text_size(txt) * ratio / 100;
+}
+
 void vis_motion_type(Vis *vis, enum VisMotionType type) {
 	vis->action.type = type;
 }
@@ -342,5 +349,6 @@ Movement vis_motions[] = {
 	[VIS_MOVE_JUMPLIST_NEXT]       = { .win = window_jumplist_next,     .type = INCLUSIVE                },
 	[VIS_MOVE_JUMPLIST_PREV]       = { .win = window_jumplist_prev,     .type = INCLUSIVE                },
 	[VIS_MOVE_NOP]                 = { .win = window_nop,               .type = IDEMPOTENT               },
+	[VIS_MOVE_PERCENT]             = { .vis = percent,                  .type = IDEMPOTENT               },
 };
 
diff --git a/vis.h b/vis.h
index 64713ef..96a9914 100644
--- a/vis.h
+++ b/vis.h
@@ -228,6 +228,7 @@ enum VisMotion {
 	VIS_MOVE_JUMPLIST_NEXT,
 	VIS_MOVE_JUMPLIST_PREV,
 	VIS_MOVE_NOP,
+	VIS_MOVE_PERCENT,
 	VIS_MOVE_INVALID, /* denotes the end of the "real" motions */
 	/* pseudo motions: keep them at the end to save space in array definition */
 	VIS_MOVE_TOTILL_REPEAT,