commit 5ed94a02a3338548633c8d745bf14fe38d3e3ffb
parent 9db0b2ad8b822f9babba7b0d472a3d20da3baf12
Author: Milos Nikic <nikic.milos@gmail.com>
Date: Sun, 18 Oct 2026 17:44:04 -0700
[ST][PATCH] Another bug fix in scrollback reflow standalone extended.
Diffstat:
2 files changed, 718 insertions(+), 1016 deletions(-)
diff --git a/st.suckless.org/patches/scrollback-reflow-standalone/st-scrollback-reflow-standalone-0.9.3.diff b/st.suckless.org/patches/scrollback-reflow-standalone/st-scrollback-reflow-standalone-0.9.3.diff
@@ -1,43 +1,35 @@
-From 3f41a815d3a0527274b1e83238e821bd286c0905 Mon Sep 17 00:00:00 2001
+From 79d001e06447448e1e0bcde47494196e61809cfa Mon Sep 17 00:00:00 2001
From: Milos Nikic <nikic.milos@gmail.com>
-Date: Thu, 15 Jan 2026 16:08:59 -0800
-Subject: [PATCH] st: alternative scrollback using ring buffer and view
- offset
+Date: Thu, 8 Jan 2026 22:04:25 -0800
+Subject: [PATCH] st: alternative scrollback using ring buffer and view offset
- Implement scrollback as a fixed-size ring buffer and render history
- by offsetting the view instead of copying screen contents.
- Implement reflow of history and screen content on resize if it is needed.
+Implement scrollback as a fixed-size ring buffer and render history
+by offsetting the view instead of copying screen contents.
- Tradeoffs / differences:
- - Scrollback is disabled on the alternate screen
- - Simpler model than the existing scrollback patch set
- - Mouse wheel scrolling enabled by default
- - Shift + page up/down and shift + end/home work as well.
- - When using vim, mouse movement will no longer move the cursor.
- - There can be visual artifacts if width of the window is shrank to the size smaller than the shell promp.
+Tradeoffs / differences:
+- Scrollback history is lost on resize
+- Scrollback is disabled on the alternate screen
+- Simpler model than the existing scrollback patch set
+- Mouse wheel scrolling enabled by default
+
+Note:
+When using vim, mouse movement will no longer move the cursor.
+
+Reminder:
+If applying this patch on top of others, ensure any changes to
+config.def.h are merged into config.h.
---
- config.def.h | 9 +
- st.c | 720 ++++++++++++++++++++++++++++++++++++++++++++-------
+ config.def.h | 5 +
+ st.c | 335 ++++++++++++++++++++++++++++++++++++++++++++++++---
st.h | 5 +
- x.c | 17 ++
- 4 files changed, 658 insertions(+), 93 deletions(-)
+ x.c | 17 +++
+ 4 files changed, 344 insertions(+), 18 deletions(-)
diff --git a/config.def.h b/config.def.h
-index 2cd740a..135a0b1 100644
+index fd2bd87..0e885f1 100644
--- a/config.def.h
+++ b/config.def.h
-@@ -192,6 +192,10 @@ static Shortcut shortcuts[] = {
- { XK_ANY_MOD, XK_Break, sendbreak, {.i = 0} },
- { ControlMask, XK_Print, toggleprinter, {.i = 0} },
- { ShiftMask, XK_Print, printscreen, {.i = 0} },
-+ { ShiftMask, XK_Page_Up, kscrollup, {.i = -1} },
-+ { ShiftMask, XK_Page_Down, kscrolldown, {.i = -1} },
-+ { ShiftMask, XK_Home, kscrollup, {.i = 1000000} },
-+ { ShiftMask, XK_End, kscrolldown, {.i = 1000000} },
- { XK_ANY_MOD, XK_Print, printsel, {.i = 0} },
- { TERMMOD, XK_Prior, zoom, {.f = +1} },
- { TERMMOD, XK_Next, zoom, {.f = -1} },
-@@ -472,3 +476,8 @@ static char ascii_printable[] =
+@@ -472,3 +472,8 @@ static char ascii_printable[] =
" !\"#$%&'()*+,-./0123456789:;<=>?"
"@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_"
"`abcdefghijklmnopqrstuvwxyz{|}~";
@@ -47,7 +39,7 @@ index 2cd740a..135a0b1 100644
+ */
+unsigned int scrollback_lines = 5000;
diff --git a/st.c b/st.c
-index e55e7b3..3b0803f 100644
+index c289072..dc30082 100644
--- a/st.c
+++ b/st.c
@@ -5,6 +5,7 @@
@@ -58,38 +50,20 @@ index e55e7b3..3b0803f 100644
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-@@ -178,7 +179,7 @@ static void tdeletechar(int);
- static void tdeleteline(int);
- static void tinsertblank(int);
- static void tinsertblankline(int);
--static int tlinelen(int);
-+static int tlinelen(Line);
- static void tmoveto(int, int);
- static void tmoveato(int, int);
- static void tnewline(int);
-@@ -232,6 +233,379 @@ static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
+@@ -232,6 +233,202 @@ static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
static const Rune utfmin[UTF_SIZ + 1] = { 0, 0, 0x80, 0x800, 0x10000};
static const Rune utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
-+typedef struct
-+{
-+ Line *buf; /* ring of Line pointers */
-+ int cap; /* max number of lines */
-+ int len; /* current number of valid lines (<= cap) */
-+ int head; /* physical index of logical oldest (valid when len>0) */
-+ uint64_t base; /* Can overflow in the extreme */
-+ /*
-+ * max_width tracks the widest line ever pushed to scrollback.
-+ * It may be conservative (stale) if that line has since been
-+ * evicted from the ring buffer, which is acceptable - it just
-+ * means we might reflow when not strictly necessary, which is
-+ * better than skipping a needed reflow.
-+ */
-+ int max_width;
-+ int view_offset; /* 0 means live screen */
++typedef struct {
++ Line *buf; /* ring of Line pointers */
++ int cap; /* max number of lines */
++ int len; /* current number of valid lines (<= cap) */
++ int head; /* physical index of logical oldest (valid when len>0) */
++ uint64_t base;
+} Scrollback;
+
+static Scrollback sb;
++static int view_offset;
+
+static int
+sb_phys_index(int logical_idx)
@@ -101,12 +75,7 @@ index e55e7b3..3b0803f 100644
+static Line
+lineclone(Line src)
+{
-+ Line dst;
-+
-+ if (!src)
-+ return NULL;
-+
-+ dst = xmalloc(term.col * sizeof(Glyph));
++ Line dst = xmalloc(term.col * sizeof(Glyph));
+ memcpy(dst, src, term.col * sizeof(Glyph));
+ return dst;
+}
@@ -124,8 +93,7 @@ index e55e7b3..3b0803f 100644
+ for (i = 0; i < sb.cap; i++)
+ sb.buf[i] = NULL;
+
-+ sb.view_offset = 0;
-+ sb.max_width = 0;
++ view_offset = 0;
+}
+
+/* Push one screen line into scrollback.
@@ -136,7 +104,6 @@ index e55e7b3..3b0803f 100644
+{
+ Line copy;
+ int tail;
-+ int width;
+
+ if (sb.cap <= 0)
+ return;
@@ -148,16 +115,11 @@ index e55e7b3..3b0803f 100644
+ sb.buf[tail] = copy;
+ sb.len++;
+ } else {
-+ /* We might've just evicted the widest line... */
+ free(sb.buf[sb.head]);
+ sb.buf[sb.head] = copy;
+ sb.head = (sb.head + 1) % sb.cap;
+ sb.base++;
+ }
-+ width = tlinelen(copy);
-+ /* ...so max_width might be stale. */
-+ if (width > sb.max_width)
-+ sb.max_width = width;
+}
+
+static Line
@@ -189,167 +151,15 @@ index e55e7b3..3b0803f 100644
+ sb.len = 0;
+ sb.head = 0;
+ sb.base = 0;
-+ sb.view_offset = 0;
-+ sb.max_width = 0;
-+}
-+
-+/*
-+ * Reflows the scrollback buffer to fit a new terminal width.
-+ *
-+ * The algorithm works in three steps:
-+ * 1) Unwrap: It iterates through the existing history, joining physical lines
-+ * marked with ATTR_WRAP into a single continuous 'logical' line.
-+ * 2) Reflow: It slices this logical line into new chunks of size 'col'.
-+ * - New wrap flags are applied where the text exceeds the new width.
-+ * - Trailing spaces are trimmed to prevent ghost padding.
-+ * 3) Rebuild: The new lines are pushed into a fresh ring buffer.
-+ * - Uses O(1) ring insertion (updating head/tail) to avoid expensive
-+ * memmoves during resize, but it is still O(N) where N is the existing
-+ * history.
-+ *
-+ * Note: During reflow we reset sb to match the rebuilt buffer
-+ * (head, base and len might change).
-+ */
-+static void
-+sb_resize(int col)
-+{
-+ Line *new_buf;
-+ int i, j;
-+ int new_len, logical_cap, logical_len, is_wrapped, cursor;
-+ int copy_width, tail, current_width;
-+ Line logical, line, nl;
-+ uint64_t new_base = 0;
-+ int new_head = 0;
-+ int new_max_width = 0;
-+ Glyph *g;
-+
-+ new_len = 0;
-+
-+ if (sb.len == 0)
-+ return;
-+
-+ new_buf = xmalloc(sizeof(Line) * sb.cap);
-+ for (i = 0; i < sb.cap; i++)
-+ new_buf[i] = NULL;
-+
-+ logical_cap = term.col * 2;
-+ logical = xmalloc(logical_cap * sizeof(Glyph));
-+ logical_len = 0;
-+
-+ for (i = 0; i < sb.len; i++) {
-+ /* Unwrap: Accumulate physical lines into one logical line. */
-+ line = sb_get(i);
-+ is_wrapped = (line[term.col - 1].mode & ATTR_WRAP);
-+ if (logical_len + term.col > logical_cap) {
-+ logical_cap *= 2;
-+ logical = xrealloc(logical, logical_cap * sizeof(Glyph));
-+ }
-+
-+ memcpy(logical + logical_len, line, term.col * sizeof(Glyph));
-+ for (j = 0; j < term.col; j++) {
-+ logical[logical_len + j].mode &= ~ATTR_WRAP;
-+ }
-+ logical_len += term.col;
-+ /* If the line was wrapped, continue accumulating before reflowing. */
-+ if (is_wrapped) {
-+ continue;
-+ }
-+ /* Trim trailing spaces from the fully unwrapped line. */
-+ while (logical_len > 0) {
-+ g = &logical[logical_len - 1];
-+ if (g->u == ' ' && g->bg == defaultbg
-+ && (g->mode & ATTR_BOLD) == 0) {
-+ logical_len--;
-+ } else {
-+ break;
-+ }
-+ }
-+ if (logical_len == 0)
-+ logical_len = 1;
-+
-+ /* Reflow: Split the logical line into new chunks. */
-+ cursor = 0;
-+ while (cursor < logical_len) {
-+ nl = xmalloc(col * sizeof(Glyph));
-+ for (j = 0; j < col; j++) {
-+ nl[j].fg = defaultfg;
-+ nl[j].bg = defaultbg;
-+ nl[j].mode = 0;
-+ nl[j].u = ' ';
-+ }
-+
-+ copy_width = logical_len - cursor;
-+ if (copy_width > col)
-+ copy_width = col;
-+
-+ memcpy(nl, logical + cursor, copy_width * sizeof(Glyph));
-+
-+ for (j = 0; j < copy_width; j++) {
-+ nl[j].mode &= ~ATTR_WRAP;
-+ }
-+
-+ if (cursor + copy_width < logical_len) {
-+ nl[col - 1].mode |= ATTR_WRAP;
-+ } else {
-+ nl[col - 1].mode &= ~ATTR_WRAP;
-+ }
-+
-+ /* Rebuild: Push new lines into the ring buffer. */
-+ if (new_len < sb.cap) {
-+ tail = (new_head + new_len) % sb.cap;
-+ new_buf[tail] = nl;
-+ new_len++;
-+ } else {
-+ free(new_buf[new_head]);
-+ new_buf[new_head] = nl;
-+ new_head = (new_head + 1) % sb.cap;
-+ new_base++;
-+ }
-+ current_width = (cursor + copy_width < logical_len) ? col : copy_width;
-+ if (current_width > new_max_width)
-+ new_max_width = current_width;
-+ cursor += copy_width;
-+ }
-+ logical_len = 0;
-+ }
-+ free(logical);
-+ sb_clear();
-+ free(sb.buf);
-+ sb.buf = new_buf;
-+ sb.len = new_len;
-+ sb.head = new_head;
-+ sb.base = new_base;
-+ sb.view_offset = 0;
-+ sb.max_width = new_max_width;
-+}
-+
-+static void
-+sb_pop_screen(int loaded, int new_cols)
-+{
-+ int i, p;
-+ int start_logical;
-+ Line line;
-+
-+ loaded = MIN(loaded, sb.len);
-+ start_logical = sb.len - loaded;
-+ new_cols = MIN(new_cols, term.col);
-+ for (i = 0; i < loaded; i++) {
-+ p = sb_phys_index(start_logical + i);
-+ line = sb.buf[p];
-+
-+ memcpy(term.line[i], line, new_cols * sizeof(Glyph));
-+
-+ free(line);
-+ sb.buf[p] = NULL;
-+ }
-+
-+ sb.len -= loaded;
++ view_offset = 0;
++ if (sel.ob.x != -1 && term.row > 0)
++ selclear();
+}
+
+static uint64_t
+sb_view_start(void)
+{
-+ return sb.base + sb.len - sb.view_offset;
++ return sb.base + sb.len - view_offset;
+}
+
+static void
@@ -366,7 +176,7 @@ index e55e7b3..3b0803f 100644
+ if (delta == 0)
+ return;
+
-+ if (sel.ob.x == -1 || sel.mode == SEL_EMPTY)
++ if (sel.ob.x == -1)
+ return;
+
+ if (sel.alt != IS_SET(MODE_ALTSCREEN))
@@ -377,7 +187,8 @@ index e55e7b3..3b0803f 100644
+ sel.ob.y += delta;
+ sel.oe.y += delta;
+
-+ if (sel.ne.y < 0 || sel.nb.y >= term.row)
++ /* the selection is in window coordinates: drop it once it leaves */
++ if (sel.nb.y < 0 || sel.ne.y >= term.row)
+ selclear();
+
+ sb_view_changed();
@@ -405,14 +216,11 @@ index e55e7b3..3b0803f 100644
+}
+
+static Line
-+renderline(int y)
++getlineforrender(int y)
+{
+ int start, v;
+
-+ if (sb.view_offset <= 0)
-+ return term.line[y];
-+
-+ start = sb.len - sb.view_offset; /* can be negative */
++ start = sb.len - view_offset; /* can be negative */
+ v = start + y;
+
+ if (v < 0)
@@ -434,8 +242,6 @@ index e55e7b3..3b0803f 100644
+{
+ sb_clear();
+ sb_view_changed();
-+ if (sel.ob.x != -1 && term.row > 0)
-+ selclear();
+}
+
+int
@@ -447,38 +253,35 @@ index e55e7b3..3b0803f 100644
ssize_t
xwrite(int fd, const char *s, size_t len)
{
-@@ -404,20 +778,23 @@ selinit(void)
- sel.ob.x = -1;
- }
-
--int
--tlinelen(int y)
-+static int
-+tlinelen(Line line)
- {
- int i = term.col;
--
-- if (term.line[y][i - 1].mode & ATTR_WRAP)
-+ if (line[i - 1].mode & ATTR_WRAP)
- return i;
--
-- while (i > 0 && term.line[y][i - 1].u == ' ')
-+ while (i > 0 && line[i - 1].u == ' ')
- --i;
--
+@@ -418,6 +615,27 @@ tlinelen(int y)
return i;
}
+static int
+tlinelen_render(int y)
+{
-+ return tlinelen(renderline(y));
++ int i;
++ Line line;
++
++ if (term.col <= 0)
++ return 0;
++
++ i = term.col;
++ line = getlineforrender(y);
++
++ if (line[i - 1].mode & ATTR_WRAP)
++ return i;
++
++ while (i > 0 && line[i - 1].u == ' ')
++ --i;
++
++ return i;
+}
+
void
selstart(int col, int row, int snap)
{
-@@ -485,10 +862,10 @@ selnormalize(void)
+@@ -485,10 +703,10 @@ selnormalize(void)
/* expand selection over line breaks */
if (sel.type == SEL_RECTANGULAR)
return;
@@ -491,7 +294,7 @@ index e55e7b3..3b0803f 100644
sel.ne.x = term.col - 1;
}
-@@ -514,6 +891,7 @@ selsnap(int *x, int *y, int direction)
+@@ -514,6 +732,7 @@ selsnap(int *x, int *y, int direction)
int newx, newy, xt, yt;
int delim, prevdelim;
const Glyph *gp, *prevgp;
@@ -499,21 +302,21 @@ index e55e7b3..3b0803f 100644
switch (sel.snap) {
case SNAP_WORD:
-@@ -521,7 +899,7 @@ selsnap(int *x, int *y, int direction)
+@@ -521,7 +740,7 @@ selsnap(int *x, int *y, int direction)
* Snap around if the word wraps around at the end or
* beginning of a line.
*/
- prevgp = &term.line[*y][*x];
-+ prevgp = &renderline(*y)[*x];
++ prevgp = &getlineforrender(*y)[*x];
prevdelim = ISDELIM(prevgp->u);
for (;;) {
newx = *x + direction;
-@@ -536,14 +914,15 @@ selsnap(int *x, int *y, int direction)
+@@ -536,14 +755,15 @@ selsnap(int *x, int *y, int direction)
yt = *y, xt = *x;
else
yt = newy, xt = newx;
- if (!(term.line[yt][xt].mode & ATTR_WRAP))
-+ line = renderline(yt);
++ line = getlineforrender(yt);
+ if (!(line[xt].mode & ATTR_WRAP))
break;
}
@@ -523,16 +326,16 @@ index e55e7b3..3b0803f 100644
break;
- gp = &term.line[newy][newx];
-+ gp = &renderline(newy)[newx];
++ gp = &getlineforrender(newy)[newx];
delim = ISDELIM(gp->u);
if (!(gp->mode & ATTR_WDUMMY) && (delim != prevdelim
|| (delim && gp->u != prevgp->u)))
-@@ -564,14 +943,14 @@ selsnap(int *x, int *y, int direction)
+@@ -564,14 +784,14 @@ selsnap(int *x, int *y, int direction)
*x = (direction < 0) ? 0 : term.col - 1;
if (direction < 0) {
for (; *y > 0; *y += direction) {
- if (!(term.line[*y-1][term.col-1].mode
-+ if (!(renderline(*y-1)[term.col-1].mode
++ if (!(getlineforrender(*y-1)[term.col-1].mode
& ATTR_WRAP)) {
break;
}
@@ -540,30 +343,17 @@ index e55e7b3..3b0803f 100644
} else if (direction > 0) {
for (; *y < term.row-1; *y += direction) {
- if (!(term.line[*y][term.col-1].mode
-+ if (!(renderline(*y)[term.col-1].mode
++ if (!(getlineforrender(*y)[term.col-1].mode
& ATTR_WRAP)) {
break;
}
-@@ -585,8 +964,9 @@ char *
- getsel(void)
- {
- char *str, *ptr;
-- int y, bufsize, lastx, linelen;
-+ int y, bufsize, lastx, linelen, end_idx, insert_newline, is_wrapped;
- const Glyph *gp, *last;
-+ Line line;
-
- if (sel.ob.x == -1)
- return NULL;
-@@ -596,29 +976,33 @@ getsel(void)
+@@ -596,19 +816,20 @@ getsel(void)
/* append every set & selected glyph to the selection */
for (y = sel.nb.y; y <= sel.ne.y; y++) {
- if ((linelen = tlinelen(y)) == 0) {
-+ line = renderline(y);
-+ linelen = tlinelen_render(y);
-+
-+ if (linelen == 0) {
++ Line line = getlineforrender(y);
++ if ((linelen = tlinelen_render(y)) == 0) {
*ptr++ = '\n';
continue;
}
@@ -578,76 +368,30 @@ index e55e7b3..3b0803f 100644
lastx = (sel.ne.y == y) ? sel.ne.x : term.col-1;
}
- last = &term.line[y][MIN(lastx, linelen-1)];
-- while (last >= gp && last->u == ' ')
-+ end_idx = MIN(lastx, linelen-1);
-+ is_wrapped = (line[end_idx].mode & ATTR_WRAP) != 0;
-+ last = &line[end_idx];
-+ while (last >= gp && last->u == ' ') {
++ last = &line[MIN(lastx, linelen-1)];
+ while (last >= gp && last->u == ' ')
--last;
-+ }
- for ( ; gp <= last; ++gp) {
- if (gp->mode & ATTR_WDUMMY)
- continue;
--
- ptr += utf8encode(gp->u, ptr);
- }
--
- /*
- * Copy and pasting of line endings is inconsistent
- * in the inconsistent terminal and GUI world.
-@@ -628,8 +1012,13 @@ getsel(void)
- * st.
- * FIXME: Fix the computer world.
- */
-+ insert_newline = 0;
- if ((y < sel.ne.y || lastx >= linelen) &&
-- (!(last->mode & ATTR_WRAP) || sel.type == SEL_RECTANGULAR))
-+ (!is_wrapped || sel.type == SEL_RECTANGULAR)) {
-+ insert_newline = 1;
-+ }
-+
-+ if (insert_newline)
- *ptr++ = '\n';
- }
- *ptr = 0;
-@@ -845,6 +1234,12 @@ ttywrite(const char *s, size_t n, int may_echo)
+@@ -848,6 +1069,12 @@ ttyread(void)
+ void
+ ttywrite(const char *s, size_t n, int may_echo)
{
- const char *next;
-
-+ if (sb.view_offset > 0) {
++ if (view_offset > 0) {
+ selclear();
-+ sb.view_offset = 0;
++ view_offset = 0;
+ sb_view_changed();
+ }
+
- if (may_echo && IS_SET(MODE_ECHO))
- twrite(s, n, 1);
-
-@@ -965,6 +1360,8 @@ tsetdirt(int top, int bot)
- {
- int i;
-
-+ if (term.row < 1)
-+ return;
- LIMIT(top, 0, term.row-1);
- LIMIT(bot, 0, term.row-1);
+ const char *next;
-@@ -1030,15 +1427,21 @@ treset(void)
- for (i = 0; i < 2; i++) {
- tmoveto(0, 0);
- tcursor(CURSOR_SAVE);
-- tclearregion(0, 0, term.col-1, term.row-1);
-+ if (term.col > 0 && term.row > 0 && term.line > 0)
-+ tclearregion(0, 0, term.col-1, term.row-1);
+ if (may_echo && IS_SET(MODE_ECHO))
+@@ -1041,12 +1268,14 @@ treset(void)
+ tclearregion(0, 0, term.col-1, term.row-1);
tswapscreen();
}
+ sb_clear();
-+ if (sel.ob.x != -1 && term.row > 0)
-+ selclear();
}
-+
void
tnew(int col, int row)
{
@@ -656,54 +400,53 @@ index e55e7b3..3b0803f 100644
tresize(col, row);
treset();
}
-@@ -1078,10 +1481,37 @@ void
+@@ -1086,10 +1315,36 @@ void
tscrollup(int orig, int n)
{
int i;
+ uint64_t newstart;
+ uint64_t oldstart;
+
-+ int attop;
Line temp;
+ oldstart = sb_view_start();
LIMIT(n, 0, term.bot-orig+1);
+ if (!IS_SET(MODE_ALTSCREEN) && orig == term.top) {
++ int attop;
++
+ /* At top of history only if history exists */
-+ attop = (sb.len != 0 && sb.view_offset == sb.len);
++ attop = (sb.len != 0 && view_offset == sb.len);
+
-+ if (sb.view_offset > 0 && !attop)
-+ sb.view_offset += n;
++ if (view_offset > 0 && !attop)
++ view_offset += n;
+
+ for (i = 0; i < n; i++)
+ sb_push(term.line[orig + i]);
+
-+ /* if at the top, keep me there */
+ if (attop)
-+ sb.view_offset = sb.len;
-+ /* otherwise clamp me */
-+ else if (sb.view_offset > sb.len)
-+ sb.view_offset = sb.len;
++ view_offset = sb.len;
++ else if (view_offset > sb.len)
++ view_offset = sb.len;
+ }
+
+ newstart = sb_view_start();
-+ if (sb.view_offset > 0)
++ if (view_offset > 0)
+ selscrollback(oldstart - newstart);
+
tclearregion(0, orig, term.col-1, orig+n-1);
tsetdirt(orig+n, term.bot);
-@@ -1097,6 +1527,8 @@ tscrollup(int orig, int n)
+@@ -1105,6 +1360,8 @@ tscrollup(int orig, int n)
void
selscroll(int orig, int n)
{
-+ if (sb.view_offset != 0)
++ if (view_offset != 0)
+ return;
if (sel.ob.x == -1 || sel.alt != IS_SET(MODE_ALTSCREEN))
return;
-@@ -1717,6 +2149,12 @@ csihandle(void)
+@@ -1727,6 +1984,12 @@ csihandle(void)
break;
case 2: /* all */
tclearregion(0, 0, term.col-1, term.row-1);
@@ -716,16 +459,7 @@ index e55e7b3..3b0803f 100644
break;
default:
goto unknown;
-@@ -2106,7 +2544,7 @@ tdumpline(int n)
- const Glyph *bp, *end;
-
- bp = &term.line[n][0];
-- end = &bp[MIN(tlinelen(n), term.col) - 1];
-+ end = &bp[MIN(tlinelen_render(n), term.col) - 1];
- if (bp != end || bp->u != ' ') {
- for ( ; bp <= end; ++bp)
- tprinter(buf, utf8encode(bp->u, buf));
-@@ -2163,6 +2601,46 @@ tdeftran(char ascii)
+@@ -2173,6 +2436,36 @@ tdeftran(char ascii)
}
}
@@ -733,12 +467,13 @@ index e55e7b3..3b0803f 100644
+kscroll(const Arg *arg)
+{
+ uint64_t oldstart;
-+ uint64_t newstart;
++ uint64_t newstart;
+
+ oldstart = sb_view_start();
-+ sb.view_offset += arg->i;
-+ LIMIT(sb.view_offset, 0, sb.len);
++ view_offset += arg->i;
++ LIMIT(view_offset, 0, sb.len);
+ newstart = sb_view_start();
++
+ selscrollback(oldstart - newstart);
+ redraw();
+}
@@ -748,228 +483,30 @@ index e55e7b3..3b0803f 100644
+{
+ Arg a;
+
-+ if (arg->i < 0)
-+ a.i = -term.row;
-+ else
-+ a.i = -arg->i;
-+
++ a.i = -arg->i;
+ kscroll(&a);
+}
+
+void
+kscrollup(const Arg *arg)
+{
-+ Arg a;
-+
-+ if (arg->i < 0)
-+ a.i = term.row;
-+ else
-+ a.i = arg->i;
-+
-+ kscroll(&a);
++ kscroll(arg);
+}
+
void
tdectest(char c)
{
-@@ -2569,83 +3047,136 @@ twrite(const char *buf, int buflen, int show_ctrl)
- void
- tresize(int col, int row)
- {
-- int i;
-+ int i, j;
-+ int min_limit;
- int minrow = MIN(row, term.row);
-- int mincol = MIN(col, term.col);
-- int *bp;
-- TCursor c;
-+ int old_row = term.row;
-+ int old_col = term.col;
-+ int save_end = 0; /* Track effective pushed height */
-+ int loaded = 0;
-+ int pop_width = 0;
-+ int needs_reflow = 0;
-+ int is_alt = IS_SET(MODE_ALTSCREEN);
-+ Line *tmp;
+@@ -2585,6 +2878,9 @@ tresize(int col, int row)
+ int *bp;
+ TCursor c;
++ sb_clear();
++ sb_view_changed();
++
if (col < 1 || row < 1) {
fprintf(stderr,
-- "tresize: error resizing to %dx%d\n", col, row);
-+ "tresize: error resizing to %dx%d\n", col, row);
- return;
- }
-
-- /*
-- * slide screen to keep cursor where we expect it -
-- * tscrollup would work here, but we can optimize to
-- * memmove because we're freeing the earlier lines
-- */
-- for (i = 0; i <= term.c.y - row; i++) {
-- free(term.line[i]);
-- free(term.alt[i]);
-- }
-- /* ensure that both src and dst are not NULL */
-- if (i > 0) {
-- memmove(term.line, term.line + i, row * sizeof(Line));
-- memmove(term.alt, term.alt + i, row * sizeof(Line));
-- }
-- for (i += row; i < term.row; i++) {
-- free(term.line[i]);
-- free(term.alt[i]);
-+ /* Operate on the currently visible screen buffer. */
-+ if (is_alt) {
-+ tmp = term.line;
-+ term.line = term.alt;
-+ term.alt = tmp;
- }
-
-- /* resize to new height */
-- term.line = xrealloc(term.line, row * sizeof(Line));
-- term.alt = xrealloc(term.alt, row * sizeof(Line));
-- term.dirty = xrealloc(term.dirty, row * sizeof(*term.dirty));
-- term.tabs = xrealloc(term.tabs, col * sizeof(*term.tabs));
-+ save_end = term.row;
-+ if (term.row != 0 && term.col != 0) {
-+ if (!is_alt && term.c.y > 0 && term.c.y < term.row) {
-+ term.line[term.c.y - 1][term.col - 1].mode &= ~ATTR_WRAP;
-+ }
-+ min_limit = is_alt ? 0 : term.c.y;
-
-- /* resize each row to new width, zero-pad if needed */
-- for (i = 0; i < minrow; i++) {
-- term.line[i] = xrealloc(term.line[i], col * sizeof(Glyph));
-- term.alt[i] = xrealloc(term.alt[i], col * sizeof(Glyph));
-- }
-+ for (i = term.row - 1; i > min_limit; i--) {
-+ if (tlinelen(term.line[i]) > 0)
-+ break;
-+ }
-+ save_end = i + 1;
-
-- /* allocate any new rows */
-- for (/* i = minrow */; i < row; i++) {
-- term.line[i] = xmalloc(col * sizeof(Glyph));
-- term.alt[i] = xmalloc(col * sizeof(Glyph));
-+ for (i = 0; i < save_end; i++) {
-+ sb_push(term.line[i]);
-+ }
-+ /* Optimization: Only reflow if content doesn't fit in new width.
-+ * This avoids expensive reflow operations when resizing doesn't
-+ * affect line wrapping (e.g., when terminal is wide enough). */
-+ if (col > term.col) {
-+ /* Growing: Only reflow if history was wrapped at old width */
-+ needs_reflow = sb.max_width >= term.col;
-+ } else if (col < term.col) {
-+ /* Shrinking: Only reflow if content is wider than new width. */
-+ if (sb.max_width > col)
-+ needs_reflow = 1;
-+ }
-+ if (needs_reflow) {
-+ sb_resize(col);
-+ } else {
-+ /* If we don't reflow, we still need to reset the view
-+ * because sb_pop_screen() might change the history length. */
-+ sb.view_offset = 0;
-+ }
- }
-- if (col > term.col) {
-- bp = term.tabs + term.col;
-
-- memset(bp, 0, sizeof(*term.tabs) * (col - term.col));
-- while (--bp > term.tabs && !*bp)
-- /* nothing */ ;
-- for (bp += tabspaces; bp < term.tabs + col; bp += tabspaces)
-- *bp = 1;
-- }
-- /* update terminal size */
-+ if (term.line) {
-+ for (i = 0; i < term.row; i++) {
-+ free(term.line[i]);
-+ free(term.alt[i]);
-+ }
-+ free(term.line);
-+ free(term.alt);
-+ free(term.dirty);
-+ free(term.tabs);
-+ }
-+
- term.col = col;
- term.row = row;
-- /* reset scrolling region */
-- tsetscroll(0, row-1);
-- /* make use of the LIMIT in tmoveto */
-- tmoveto(term.c.x, term.c.y);
-- /* Clearing both screens (it makes dirty all lines) */
-- c = term.c;
-- for (i = 0; i < 2; i++) {
-- if (mincol < col && 0 < minrow) {
-- tclearregion(mincol, 0, col - 1, minrow - 1);
-- }
-- if (0 < col && minrow < row) {
-- tclearregion(0, minrow, col - 1, row - 1);
-+
-+ term.line = xmalloc(term.row * sizeof(Line));
-+ term.alt = xmalloc(term.row * sizeof(Line));
-+ term.dirty = xmalloc(term.row * sizeof(int));
-+ term.tabs = xmalloc(term.col * sizeof(*term.tabs));
-+
-+ for (i = 0; i < term.row; i++) {
-+ term.line[i] = xmalloc(term.col * sizeof(Glyph));
-+ term.alt[i] = xmalloc(term.col * sizeof(Glyph));
-+ term.dirty[i] = 1;
-+
-+ for (j = 0; j < term.col; j++) {
-+ term.line[i][j] = term.c.attr;
-+ term.line[i][j].u = ' ';
-+ term.line[i][j].mode = 0;
-+
-+ term.alt[i][j] = term.c.attr;
-+ term.alt[i][j].u = ' ';
-+ term.alt[i][j].mode = 0;
- }
-- tswapscreen();
-- tcursor(CURSOR_LOAD);
- }
-- term.c = c;
-+
-+ memset(term.tabs, 0, term.col * sizeof(*term.tabs));
-+ for (i = 8; i < term.col; i += 8)
-+ term.tabs[i] = 1;
-+
-+ tsetscroll(0, term.row - 1);
-+
-+ if (minrow > 0) {
-+ loaded = MIN(sb.len, term.row);
-+ pop_width = needs_reflow ? col : MIN(col, old_col);
-+ sb_pop_screen(loaded, pop_width);
-+ }
-+ if (is_alt) {
-+ tmp = term.line;
-+ term.line = term.alt;
-+ term.alt = tmp;
-+ }
-+ if (!is_alt && old_row > 0) {
-+ term.c.y += (loaded - save_end);
-+ }
-+ if (term.c.y >= term.row) {
-+ term.c.y = term.row - 1;
-+ }
-+ if (term.c.x >= term.col) {
-+ term.c.x = term.col - 1;
-+ }
-+ if (term.c.y < 0) {
-+ term.c.y = 0;
-+ }
-+ if (term.c.x < 0) {
-+ term.c.x = 0;
-+ }
-+
-+ tfulldirt();
-+ sb_view_changed();
- }
-
- void
-@@ -2659,12 +3190,13 @@ drawregion(int x1, int y1, int x2, int y2)
+ "tresize: error resizing to %dx%d\n", col, row);
+@@ -2669,12 +2965,13 @@ drawregion(int x1, int y1, int x2, int y2)
{
int y;
@@ -980,12 +517,12 @@ index e55e7b3..3b0803f 100644
-
term.dirty[y] = 0;
- xdrawline(term.line[y], x1, y, x2);
-+ line = renderline(y);
++ line = getlineforrender(y);
+ xdrawline(line, x1, y, x2);
}
}
-@@ -2685,10 +3217,12 @@ draw(void)
+@@ -2695,10 +2992,12 @@ draw(void)
cx--;
drawregion(0, 0, term.col, term.row);
@@ -993,7 +530,7 @@ index e55e7b3..3b0803f 100644
- term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
- term.ocx = cx;
- term.ocy = term.c.y;
-+ if (sb.view_offset == 0) {
++ if (view_offset == 0) {
+ xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
+ term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
+ term.ocx = cx;
@@ -1030,7 +567,7 @@ index fd3b0d8..151d0c6 100644
extern unsigned int defaultcs;
+extern unsigned int scrollback_lines;
diff --git a/x.c b/x.c
-index d73152b..75f3db1 100644
+index 76f572d..dfe416a 100644
--- a/x.c
+++ b/x.c
@@ -472,6 +472,23 @@ bpress(XEvent *e)
@@ -1058,5 +595,5 @@ index d73152b..75f3db1 100644
buttons |= 1 << (btn-1);
--
-2.52.0
+2.56.0
diff --git a/st.suckless.org/patches/scrollback-reflow-standalone/st-scrollback-reflow-standalone-extended-0.9.3.diff b/st.suckless.org/patches/scrollback-reflow-standalone/st-scrollback-reflow-standalone-extended-0.9.3.diff
@@ -1,56 +1,39 @@
-From 792cbb832839cb6981440356c26ce2836bc69427 Mon Sep 17 00:00:00 2001
+From 5fbf33797d8d286b94a69babbfee014f58dfe87e Mon Sep 17 00:00:00 2001
From: Milos Nikic <nikic.milos@gmail.com>
-Date: Thu, 8 Jan 2026 22:04:25 -0800
-Subject: [PATCH] st: alternative scrollback using ring buffer and view offset
+Date: Sun, 18 Oct 2026 11:58:07 -0700
+Subject: [PATCH] st: scrollback reflow and selection across scrollback
-Implement scrollback as a fixed-size ring buffer and render history
-by offsetting the view instead of copying screen contents.
+Reflow the scrollback buffer on resize instead of dropping it: wrapped
+lines are joined into logical lines and re-split to the new width.
-Tradeoffs / differences:
-- Scrollback history is lost on resize
-- Scrollback is disabled on the alternate screen
-- Simpler model than the existing scrollback patch set
-- Mouse wheel scrolling enabled by default
+Keep the selection in logical rows spanning history and screen (0 is
+the oldest scrollback line, sb.len + y is screen row y) instead of in
+window coordinates. Lines keep their row when pushed into scrollback,
+so the selection now survives scrolling the view and new output, and
+can cover more than one screen. Only evicting the oldest line from the
+ring shifts it.
-Note:
-When using vim, mouse movement will no longer move the cursor.
+- shift+click extends the current selection: the end nearest to the
+ click follows it, keeping word/line snapping. Disabled in MODE_MOUSE,
+ where shift forces selection instead.
+- scrolling the wheel while dragging keeps the selection end under the
+ pointer.
+- typing while scrolled back no longer clears the selection.
+- the selection is cleared when the width changes (reflow) or the alt
+ screen is resized, and kept on height-only resizes.
-Reminder:
-If applying this patch on top of others, ensure any changes to
-config.def.h are merged into config.h.
+Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
- config.def.h | 5 +
- st.c | 713 ++++++++++++++++++++++++++++++++++++++++++++-------
- st.h | 5 +
- x.c | 17 ++
- 4 files changed, 645 insertions(+), 95 deletions(-)
+ st.c | 707 +++++++++++++++++++++++++++++++++++++++++++----------------
+ st.h | 1 +
+ x.c | 29 ++-
+ 3 files changed, 537 insertions(+), 200 deletions(-)
-diff --git a/config.def.h b/config.def.h
-index 2cd740a..a0b14e9 100644
---- a/config.def.h
-+++ b/config.def.h
-@@ -472,3 +472,8 @@ static char ascii_printable[] =
- " !\"#$%&'()*+,-./0123456789:;<=>?"
- "@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_"
- "`abcdefghijklmnopqrstuvwxyz{|}~";
-+
-+/*
-+ * The amount of lines scrollback can hold before it wraps around.
-+ */
-+unsigned int scrollback_lines = 5000;
diff --git a/st.c b/st.c
-index 6f40e35..cf76c58 100644
+index dc30082..4d79f20 100644
--- a/st.c
+++ b/st.c
-@@ -5,6 +5,7 @@
- #include <limits.h>
- #include <pwd.h>
- #include <stdarg.h>
-+#include <stdint.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
-@@ -178,7 +179,7 @@ static void tdeletechar(int);
+@@ -179,7 +179,7 @@ static void tdeletechar(int);
static void tdeleteline(int);
static void tinsertblank(int);
static void tinsertblankline(int);
@@ -59,10 +42,26 @@ index 6f40e35..cf76c58 100644
static void tmoveto(int, int);
static void tmoveato(int, int);
static void tnewline(int);
-@@ -232,6 +233,379 @@ static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
+@@ -208,6 +208,9 @@ static void drawregion(int, int, int, int);
+ static void selnormalize(void);
+ static void selscroll(int, int);
+ static void selsnap(int *, int *, int);
++static void selevict(void);
++static void seldirt(int, int);
++static int isselected(int, int);
+
+ static size_t utf8decode(const char *, Rune *, size_t);
+ static Rune utf8decodebyte(char, size_t *);
+@@ -233,16 +236,25 @@ static const uchar utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
static const Rune utfmin[UTF_SIZ + 1] = { 0, 0, 0x80, 0x800, 0x10000};
static const Rune utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};
+-typedef struct {
+- Line *buf; /* ring of Line pointers */
+- int cap; /* max number of lines */
+- int len; /* current number of valid lines (<= cap) */
+- int head; /* physical index of logical oldest (valid when len>0) */
+- uint64_t base;
+typedef struct
+{
+ Line *buf; /* ring of Line pointers */
@@ -79,112 +78,80 @@ index 6f40e35..cf76c58 100644
+ */
+ int max_width;
+ int view_offset; /* 0 means live screen */
-+} Scrollback;
-+
-+static Scrollback sb;
-+
-+static int
-+sb_phys_index(int logical_idx)
-+{
-+ /* logical_idx: 0..sb.len-1 (0 = oldest) */
-+ return (sb.head + logical_idx) % sb.cap;
-+}
-+
-+static Line
-+lineclone(Line src)
-+{
+ } Scrollback;
+
+ static Scrollback sb;
+-static int view_offset;
+
+ static int
+ sb_phys_index(int logical_idx)
+@@ -254,7 +266,12 @@ sb_phys_index(int logical_idx)
+ static Line
+ lineclone(Line src)
+ {
+- Line dst = xmalloc(term.col * sizeof(Glyph));
+ Line dst;
+
+ if (!src)
+ return NULL;
+
+ dst = xmalloc(term.col * sizeof(Glyph));
-+ memcpy(dst, src, term.col * sizeof(Glyph));
-+ return dst;
-+}
-+
-+static void
-+sb_init(int lines)
-+{
-+ int i;
-+
-+ sb.buf = xmalloc(sizeof(Line) * lines);
-+ sb.cap = lines;
-+ sb.len = 0;
-+ sb.head = 0;
-+ sb.base = 0;
-+ for (i = 0; i < sb.cap; i++)
-+ sb.buf[i] = NULL;
-+
+ memcpy(dst, src, term.col * sizeof(Glyph));
+ return dst;
+ }
+@@ -272,7 +289,8 @@ sb_init(int lines)
+ for (i = 0; i < sb.cap; i++)
+ sb.buf[i] = NULL;
+
+- view_offset = 0;
+ sb.view_offset = 0;
+ sb.max_width = 0;
-+}
-+
-+/* Push one screen line into scrollback.
-+ * Overwrites oldest when full (ring buffer).
-+ */
-+static void
-+sb_push(Line line)
-+{
-+ Line copy;
-+ int tail;
+ }
+
+ /* Push one screen line into scrollback.
+@@ -283,6 +301,7 @@ sb_push(Line line)
+ {
+ Line copy;
+ int tail;
+ int width;
-+
-+ if (sb.cap <= 0)
-+ return;
-+
-+ copy = lineclone(line);
-+
-+ if (sb.len < sb.cap) {
-+ tail = sb_phys_index(sb.len);
-+ sb.buf[tail] = copy;
-+ sb.len++;
-+ } else {
+
+ if (sb.cap <= 0)
+ return;
+@@ -294,11 +313,17 @@ sb_push(Line line)
+ sb.buf[tail] = copy;
+ sb.len++;
+ } else {
+ /* We might've just evicted the widest line... */
-+ free(sb.buf[sb.head]);
-+ sb.buf[sb.head] = copy;
-+ sb.head = (sb.head + 1) % sb.cap;
-+ sb.base++;
-+ }
+ free(sb.buf[sb.head]);
+ sb.buf[sb.head] = copy;
+ sb.head = (sb.head + 1) % sb.cap;
+ sb.base++;
++ selevict();
+ }
+ width = tlinelen(copy);
+ /* ...so max_width might be stale. */
+ if (width > sb.max_width)
+ sb.max_width = width;
-+}
-+
-+static Line
-+sb_get(int idx)
-+{
-+ /* idx is logical: 0..sb.len-1 */
-+ if (idx < 0 || idx >= sb.len)
-+ return NULL;
-+ return sb.buf[sb_phys_index(idx)];
-+}
-+
-+static void
-+sb_clear(void)
-+{
-+ int i;
-+ int p;
-+
-+ if (!sb.buf)
-+ return;
-+
-+ for (i = 0; i < sb.len; i++) {
-+ p = sb_phys_index(i);
-+ if (sb.buf[p]) {
-+ free(sb.buf[p]);
-+ sb.buf[p] = NULL;
-+ }
-+ }
-+
-+ sb.len = 0;
-+ sb.head = 0;
-+ sb.base = 0;
+ }
+
+ static Line
+@@ -330,47 +355,169 @@ sb_clear(void)
+ sb.len = 0;
+ sb.head = 0;
+ sb.base = 0;
+- view_offset = 0;
+- if (sel.ob.x != -1 && term.row > 0)
+- selclear();
+-}
+-
+-static uint64_t
+-sb_view_start(void)
+-{
+- return sb.base + sb.len - view_offset;
+ sb.view_offset = 0;
+ sb.max_width = 0;
-+}
-+
+ }
+
+/*
+ * Reflows the scrollback buffer to fit a new terminal width.
+ *
@@ -202,9 +169,11 @@ index 6f40e35..cf76c58 100644
+ * Note: During reflow we reset sb to match the rebuilt buffer
+ * (head, base and len might change).
+ */
-+static void
+ static void
+-sb_view_changed(void)
+sb_resize(int col)
-+{
+ {
+- if (!term.dirty || term.row <= 0)
+ Line *new_buf;
+ int i, j;
+ int new_len, logical_cap, logical_len, is_wrapped, cursor;
@@ -218,7 +187,8 @@ index 6f40e35..cf76c58 100644
+ new_len = 0;
+
+ if (sb.len == 0)
-+ return;
+ return;
+- tfulldirt();
+
+ new_buf = xmalloc(sizeof(Line) * sb.cap);
+ for (i = 0; i < sb.cap; i++)
@@ -313,133 +283,116 @@ index 6f40e35..cf76c58 100644
+ sb.base = new_base;
+ sb.view_offset = 0;
+ sb.max_width = new_max_width;
-+}
-+
-+static void
+ }
+
+ static void
+-selscrollback(int delta)
+sb_pop_screen(int loaded, int new_cols)
-+{
+ {
+- if (delta == 0)
+- return;
+ int i, p;
+ int start_logical;
+ Line line;
-+
+
+- if (sel.ob.x == -1)
+- return;
+ loaded = MIN(loaded, sb.len);
+ start_logical = sb.len - loaded;
+ new_cols = MIN(new_cols, term.col);
+ for (i = 0; i < loaded; i++) {
+ p = sb_phys_index(start_logical + i);
+ line = sb.buf[p];
-+
+
+- if (sel.alt != IS_SET(MODE_ALTSCREEN))
+- return;
+ memcpy(term.line[i], line, new_cols * sizeof(Glyph));
-+
+
+- sel.nb.y += delta;
+- sel.ne.y += delta;
+- sel.ob.y += delta;
+- sel.oe.y += delta;
+ free(line);
+ sb.buf[p] = NULL;
+ }
-+
+
+- /* the selection is in window coordinates: drop it once it leaves */
+- if (sel.nb.y < 0 || sel.ne.y >= term.row)
+- selclear();
+ sb.len -= loaded;
+}
-+
-+static uint64_t
-+sb_view_start(void)
-+{
-+ return sb.base + sb.len - sb.view_offset;
-+}
-+
+
+- sb_view_changed();
+static void
+sb_view_changed(void)
+{
+ if (!term.dirty || term.row <= 0)
+ return;
+ tfulldirt();
-+}
-+
-+static void
-+selscrollback(int delta)
-+{
-+ if (delta == 0)
-+ return;
-+
-+ if (sel.ob.x == -1 || sel.mode == SEL_EMPTY)
-+ return;
-+
-+ if (sel.alt != IS_SET(MODE_ALTSCREEN))
-+ return;
-+
-+ sel.nb.y += delta;
-+ sel.ne.y += delta;
-+ sel.ob.y += delta;
-+ sel.oe.y += delta;
-+
-+ if (sel.ne.y < 0 || sel.nb.y >= term.row)
-+ selclear();
-+
-+ sb_view_changed();
-+}
-+
-+static Line
-+emptyline(void)
+ }
+
+ static Line
+@@ -394,14 +541,16 @@ emptyline(void)
+ return empty;
+ }
+
++/*
++ * Logical rows address history and screen as one continuous space:
++ * 0..sb.len-1 are scrollback lines (0 = oldest) and sb.len + y is
++ * screen row y. A line keeps its logical row when it is pushed into
++ * scrollback; only evicting the oldest line shifts everything by one.
++ * The selection lives in this space, so it survives scrolling.
++ */
+ static Line
+-getlineforrender(int y)
++logicalline(int v)
+ {
+- int start, v;
+-
+- start = sb.len - view_offset; /* can be negative */
+- v = start + y;
+-
+ if (v < 0)
+ return emptyline();
+
+@@ -410,17 +559,35 @@ getlineforrender(int y)
+
+ /* past scrollback -> into current screen */
+ v -= sb.len;
+- if (v >= 0 && v < term.row)
++ if (v < term.row)
+ return term.line[v];
+
+ return emptyline();
+ }
+
++/* first logical row shown at the top of the window */
++static int
++viewtop(void)
+{
-+ static Line empty;
-+ static int empty_cols;
-+ int i = 0;
-+
-+ if (empty_cols != term.col) {
-+ free(empty);
-+ empty = xmalloc(term.col * sizeof(Glyph));
-+ empty_cols = term.col;
-+ }
-+
-+ for (i = 0; i < term.col; i++) {
-+ empty[i] = term.c.attr;
-+ empty[i].u = ' ';
-+ empty[i].mode = 0;
-+ }
-+ return empty;
++ return sb.len - sb.view_offset; /* can be negative */
+}
+
+static Line
+renderline(int y)
+{
-+ int start, v;
-+
+ if (sb.view_offset <= 0)
+ return term.line[y];
+
-+ start = sb.len - sb.view_offset; /* can be negative */
-+ v = start + y;
-+
-+ if (v < 0)
-+ return emptyline();
-+
-+ if (v < sb.len)
-+ return sb_get(v);
-+
-+ /* past scrollback -> into current screen */
-+ v -= sb.len;
-+ if (v >= 0 && v < term.row)
-+ return term.line[v];
-+
-+ return emptyline();
++ return logicalline(viewtop() + y);
+}
+
-+static void
-+sb_reset_on_clear(void)
-+{
-+ sb_clear();
-+ sb_view_changed();
+ static void
+ sb_reset_on_clear(void)
+ {
+ sb_clear();
+ sb_view_changed();
+ if (sel.ob.x != -1 && term.row > 0)
+ selclear();
-+}
-+
-+int
-+tisaltscreen(void)
-+{
-+ return IS_SET(MODE_ALTSCREEN);
-+}
-+
- ssize_t
- xwrite(int fd, const char *s, size_t len)
- {
-@@ -404,20 +778,23 @@ selinit(void)
+ }
+
+ int
+@@ -601,39 +768,66 @@ selinit(void)
sel.ob.x = -1;
}
@@ -461,82 +414,235 @@ index 6f40e35..cf76c58 100644
return i;
}
++/* range of logical rows a selection can cover */
+ static int
+-tlinelen_render(int y)
++selminrow(void)
+ {
+- int i;
+- Line line;
++ /* the alternate screen has no history */
++ return sel.alt ? sb.len : 0;
++}
+
+- if (term.col <= 0)
+- return 0;
+static int
-+tlinelen_render(int y)
++selmaxrow(void)
+{
-+ return tlinelen(renderline(y));
++ return sb.len + term.row - 1;
++}
+
+- i = term.col;
+- line = getlineforrender(y);
++/* mark the visible part of logical rows a..b dirty */
++static void
++seldirt(int a, int b)
++{
++ int top = viewtop();
+
+- if (line[i - 1].mode & ATTR_WRAP)
+- return i;
++ a -= top;
++ b -= top;
++ if (b < 0 || a >= term.row)
++ return;
++ tsetdirt(MAX(a, 0), MIN(b, term.row - 1));
++}
+
+- while (i > 0 && line[i - 1].u == ' ')
+- --i;
++/* the oldest scrollback line was dropped: shift the selection with it */
++static void
++selevict(void)
++{
++ if (sel.ob.x == -1 || sel.alt)
++ return;
+
+- return i;
++ sel.ob.y--;
++ sel.oe.y--;
++ sel.nb.y--;
++ sel.ne.y--;
++
++ if (sel.ne.y < 0) {
++ selclear();
++ return;
++ }
++ if (sel.nb.y < 0)
++ sel.nb.x = sel.nb.y = 0;
++ if (sel.ob.y < 0)
++ sel.ob.x = sel.ob.y = 0;
++ if (sel.oe.y < 0)
++ sel.oe.x = sel.oe.y = 0;
+ }
+
+ void
+@@ -645,12 +839,12 @@ selstart(int col, int row, int snap)
+ sel.alt = IS_SET(MODE_ALTSCREEN);
+ sel.snap = snap;
+ sel.oe.x = sel.ob.x = col;
+- sel.oe.y = sel.ob.y = row;
++ sel.oe.y = sel.ob.y = viewtop() + row;
+ selnormalize();
+
+ if (sel.snap != 0)
+ sel.mode = SEL_READY;
+- tsetdirt(sel.nb.y, sel.ne.y);
++ seldirt(sel.nb.y, sel.ne.y);
+ }
+
+ void
+@@ -672,16 +866,48 @@ selextend(int col, int row, int type, int done)
+ oldtype = sel.type;
+
+ sel.oe.x = col;
+- sel.oe.y = row;
++ sel.oe.y = viewtop() + row;
+ selnormalize();
+ sel.type = type;
+
+ if (oldey != sel.oe.y || oldex != sel.oe.x || oldtype != sel.type || sel.mode == SEL_EMPTY)
+- tsetdirt(MIN(sel.nb.y, oldsby), MAX(sel.ne.y, oldsey));
++ seldirt(MIN(sel.nb.y, oldsby), MAX(sel.ne.y, oldsey));
+
+ sel.mode = done ? SEL_IDLE : SEL_READY;
+ }
+
++/*
++ * Extend the existing selection to (col, row): the end closest to the
++ * click follows it, the other end stays put. The selection can then be
++ * dragged further like a fresh one. Returns 0 if there is nothing to
++ * extend.
++ */
++int
++selextendto(int col, int row, int type)
++{
++ long pos, dbeg, dend;
++
++ if (sel.ob.x == -1 || sel.mode != SEL_IDLE ||
++ sel.alt != IS_SET(MODE_ALTSCREEN))
++ return 0;
++
++ row += viewtop();
++ pos = (long)row * term.col + col;
++ dbeg = labs(pos - ((long)sel.nb.y * term.col + sel.nb.x));
++ dend = labs(pos - ((long)sel.ne.y * term.col + sel.ne.x));
++
++ seldirt(sel.nb.y, sel.ne.y);
++ sel.ob = (dbeg < dend) ? sel.ne : sel.nb;
++ sel.oe.x = col;
++ sel.oe.y = row;
++ sel.type = type;
++ selnormalize();
++ seldirt(sel.nb.y, sel.ne.y);
++ sel.mode = SEL_READY;
++
++ return 1;
+}
+
void
- selstart(int col, int row, int snap)
+ selnormalize(void)
{
-@@ -485,10 +862,10 @@ selnormalize(void)
+@@ -703,15 +929,16 @@ selnormalize(void)
/* expand selection over line breaks */
if (sel.type == SEL_RECTANGULAR)
return;
-- i = tlinelen(sel.nb.y);
-+ i = tlinelen_render(sel.nb.y);
+- i = tlinelen_render(sel.nb.y);
++ i = tlinelen(logicalline(sel.nb.y));
if (i < sel.nb.x)
sel.nb.x = i;
-- if (tlinelen(sel.ne.y) <= sel.ne.x)
-+ if (tlinelen_render(sel.ne.y) <= sel.ne.x)
+- if (tlinelen_render(sel.ne.y) <= sel.ne.x)
++ if (tlinelen(logicalline(sel.ne.y)) <= sel.ne.x)
sel.ne.x = term.col - 1;
}
-@@ -514,6 +891,7 @@ selsnap(int *x, int *y, int direction)
+-int
+-selected(int x, int y)
++/* x, y in logical rows */
++static int
++isselected(int x, int y)
+ {
+ if (sel.mode == SEL_EMPTY || sel.ob.x == -1 ||
+ sel.alt != IS_SET(MODE_ALTSCREEN))
+@@ -726,11 +953,19 @@ selected(int x, int y)
+ && (y != sel.ne.y || x <= sel.ne.x);
+ }
+
++/* x, y in window coordinates */
++int
++selected(int x, int y)
++{
++ return isselected(x, viewtop() + y);
++}
++
+ void
+ selsnap(int *x, int *y, int direction)
+ {
int newx, newy, xt, yt;
int delim, prevdelim;
++ int miny = selminrow(), maxy = selmaxrow();
const Glyph *gp, *prevgp;
-+ Line line;
+ Line line;
- switch (sel.snap) {
- case SNAP_WORD:
-@@ -521,7 +899,7 @@ selsnap(int *x, int *y, int direction)
+@@ -740,7 +975,7 @@ selsnap(int *x, int *y, int direction)
* Snap around if the word wraps around at the end or
* beginning of a line.
*/
-- prevgp = &term.line[*y][*x];
-+ prevgp = &renderline(*y)[*x];
+- prevgp = &getlineforrender(*y)[*x];
++ prevgp = &logicalline(*y)[*x];
prevdelim = ISDELIM(prevgp->u);
for (;;) {
newx = *x + direction;
-@@ -536,14 +914,15 @@ selsnap(int *x, int *y, int direction)
+@@ -748,22 +983,23 @@ selsnap(int *x, int *y, int direction)
+ if (!BETWEEN(newx, 0, term.col - 1)) {
+ newy += direction;
+ newx = (newx + term.col) % term.col;
+- if (!BETWEEN(newy, 0, term.row - 1))
++ if (!BETWEEN(newy, miny, maxy))
+ break;
+
+ if (direction > 0)
yt = *y, xt = *x;
else
yt = newy, xt = newx;
-- if (!(term.line[yt][xt].mode & ATTR_WRAP))
-+ line = renderline(yt);
-+ if (!(line[xt].mode & ATTR_WRAP))
+- line = getlineforrender(yt);
++ line = logicalline(yt);
+ if (!(line[xt].mode & ATTR_WRAP))
break;
}
-- if (newx >= tlinelen(newy))
-+ if (newx >= tlinelen_render(newy))
+- if (newx >= tlinelen_render(newy))
++ line = logicalline(newy);
++ if (newx >= tlinelen(line))
break;
-- gp = &term.line[newy][newx];
-+ gp = &renderline(newy)[newx];
+- gp = &getlineforrender(newy)[newx];
++ gp = &line[newx];
delim = ISDELIM(gp->u);
if (!(gp->mode & ATTR_WDUMMY) && (delim != prevdelim
|| (delim && gp->u != prevgp->u)))
-@@ -564,14 +943,14 @@ selsnap(int *x, int *y, int direction)
+@@ -783,15 +1019,15 @@ selsnap(int *x, int *y, int direction)
+ */
*x = (direction < 0) ? 0 : term.col - 1;
if (direction < 0) {
- for (; *y > 0; *y += direction) {
-- if (!(term.line[*y-1][term.col-1].mode
-+ if (!(renderline(*y-1)[term.col-1].mode
+- for (; *y > 0; *y += direction) {
+- if (!(getlineforrender(*y-1)[term.col-1].mode
++ for (; *y > miny; *y += direction) {
++ if (!(logicalline(*y-1)[term.col-1].mode
& ATTR_WRAP)) {
break;
}
}
} else if (direction > 0) {
- for (; *y < term.row-1; *y += direction) {
-- if (!(term.line[*y][term.col-1].mode
-+ if (!(renderline(*y)[term.col-1].mode
+- for (; *y < term.row-1; *y += direction) {
+- if (!(getlineforrender(*y)[term.col-1].mode
++ for (; *y < maxy; *y += direction) {
++ if (!(logicalline(*y)[term.col-1].mode
& ATTR_WRAP)) {
break;
}
-@@ -585,8 +964,9 @@ char *
+@@ -805,8 +1041,9 @@ char *
getsel(void)
{
char *str, *ptr;
@@ -547,29 +653,24 @@ index 6f40e35..cf76c58 100644
if (sel.ob.x == -1)
return NULL;
-@@ -596,29 +976,33 @@ getsel(void)
+@@ -816,8 +1053,10 @@ getsel(void)
/* append every set & selected glyph to the selection */
for (y = sel.nb.y; y <= sel.ne.y; y++) {
-- if ((linelen = tlinelen(y)) == 0) {
-+ line = renderline(y);
-+ linelen = tlinelen_render(y);
+- Line line = getlineforrender(y);
+- if ((linelen = tlinelen_render(y)) == 0) {
++ line = logicalline(y);
++ linelen = tlinelen(line);
+
+ if (linelen == 0) {
*ptr++ = '\n';
continue;
}
-
- if (sel.type == SEL_RECTANGULAR) {
-- gp = &term.line[y][sel.nb.x];
-+ gp = &line[sel.nb.x];
- lastx = sel.ne.x;
- } else {
-- gp = &term.line[y][sel.nb.y == y ? sel.nb.x : 0];
-+ gp = &line[sel.nb.y == y ? sel.nb.x : 0];
+@@ -829,17 +1068,18 @@ getsel(void)
+ gp = &line[sel.nb.y == y ? sel.nb.x : 0];
lastx = (sel.ne.y == y) ? sel.ne.x : term.col-1;
}
-- last = &term.line[y][MIN(lastx, linelen-1)];
+- last = &line[MIN(lastx, linelen-1)];
- while (last >= gp && last->u == ' ')
+ end_idx = MIN(lastx, linelen-1);
+ is_wrapped = (line[end_idx].mode & ATTR_WRAP) != 0;
@@ -588,7 +689,7 @@ index 6f40e35..cf76c58 100644
/*
* Copy and pasting of line endings is inconsistent
* in the inconsistent terminal and GUI world.
-@@ -628,8 +1012,13 @@ getsel(void)
+@@ -849,8 +1089,13 @@ getsel(void)
* st.
* FIXME: Fix the computer world.
*/
@@ -603,20 +704,35 @@ index 6f40e35..cf76c58 100644
*ptr++ = '\n';
}
*ptr = 0;
-@@ -845,6 +1234,12 @@ ttywrite(const char *s, size_t n, int may_echo)
- {
- const char *next;
+@@ -864,7 +1109,7 @@ selclear(void)
+ return;
+ sel.mode = SEL_IDLE;
+ sel.ob.x = -1;
+- tsetdirt(sel.nb.y, sel.ne.y);
++ seldirt(sel.nb.y, sel.ne.y);
+ }
+ void
+@@ -1069,14 +1314,13 @@ ttyread(void)
+ void
+ ttywrite(const char *s, size_t n, int may_echo)
+ {
+- if (view_offset > 0) {
+- selclear();
+- view_offset = 0;
++ const char *next;
++
+ if (sb.view_offset > 0) {
-+ selclear();
+ sb.view_offset = 0;
-+ sb_view_changed();
-+ }
-+
+ sb_view_changed();
+ }
+
+- const char *next;
+-
if (may_echo && IS_SET(MODE_ECHO))
twrite(s, n, 1);
-@@ -965,9 +1360,8 @@ tsetdirt(int top, int bot)
+@@ -1197,9 +1441,8 @@ tsetdirt(int top, int bot)
{
int i;
@@ -627,16 +743,16 @@ index 6f40e35..cf76c58 100644
LIMIT(top, 0, term.row-1);
LIMIT(bot, 0, term.row-1);
-@@ -1033,15 +1427,21 @@ treset(void)
+@@ -1265,12 +1508,16 @@ treset(void)
for (i = 0; i < 2; i++) {
tmoveto(0, 0);
tcursor(CURSOR_SAVE);
- tclearregion(0, 0, term.col-1, term.row-1);
-+ if (term.col > 0 && term.row > 0 && term.line > 0)
++ if (term.col > 0 && term.row > 0 && term.line)
+ tclearregion(0, 0, term.col-1, term.row-1);
tswapscreen();
}
-+ sb_clear();
+ sb_clear();
+ if (sel.ob.x != -1 && term.row > 0)
+ selclear();
}
@@ -645,118 +761,150 @@ index 6f40e35..cf76c58 100644
void
tnew(int col, int row)
{
- term = (Term){ .c = { .attr = { .fg = defaultfg, .bg = defaultbg } } };
-+ sb_init(scrollback_lines);
- tresize(col, row);
- treset();
- }
-@@ -1081,10 +1481,37 @@ void
+@@ -1315,35 +1562,53 @@ void
tscrollup(int orig, int n)
{
int i;
-+ uint64_t newstart;
-+ uint64_t oldstart;
-+
+- uint64_t newstart;
+- uint64_t oldstart;
+-
+ int attop;
++ int pushed = 0;
Line temp;
-+ oldstart = sb_view_start();
+- oldstart = sb_view_start();
LIMIT(n, 0, term.bot-orig+1);
-+ if (!IS_SET(MODE_ALTSCREEN) && orig == term.top) {
-+ /* At top of history only if history exists */
+ if (!IS_SET(MODE_ALTSCREEN) && orig == term.top) {
+- int attop;
++ /*
++ * Pushed lines keep their logical rows, but rows outside
++ * of a partial scroll region move along with the screen.
++ */
++ if ((term.top > 0 || term.bot < term.row-1) &&
++ sel.ob.x != -1 && !sel.alt && sel.ne.y >= sb.len)
++ selclear();
+
+ /* At top of history only if history exists */
+- attop = (sb.len != 0 && view_offset == sb.len);
+ attop = (sb.len != 0 && sb.view_offset == sb.len);
-+
+
+- if (view_offset > 0 && !attop)
+- view_offset += n;
+ if (sb.view_offset > 0 && !attop)
+ sb.view_offset += n;
-+
-+ for (i = 0; i < n; i++)
-+ sb_push(term.line[orig + i]);
-+
+
+ for (i = 0; i < n; i++)
+ sb_push(term.line[orig + i]);
++ pushed = sb.cap > 0;
+
+ /* if at the top, keep me there */
-+ if (attop)
+ if (attop)
+- view_offset = sb.len;
+- else if (view_offset > sb.len)
+- view_offset = sb.len;
+ sb.view_offset = sb.len;
+ /* otherwise clamp me */
+ else if (sb.view_offset > sb.len)
+ sb.view_offset = sb.len;
+ }
+
+- newstart = sb_view_start();
+- if (view_offset > 0)
+- selscrollback(oldstart - newstart);
++ if (pushed) {
++ /*
++ * The lines went to history, so the selection stays valid.
++ * Rotate before clearing, so clearing doesn't drop it.
++ */
++ tsetdirt(orig, term.bot);
++ for (i = orig; i <= term.bot-n; i++) {
++ temp = term.line[i];
++ term.line[i] = term.line[i+n];
++ term.line[i+n] = temp;
++ }
++ tclearregion(0, term.bot-n+1, term.col-1, term.bot);
++ return;
+ }
-+
-+ newstart = sb_view_start();
-+ if (sb.view_offset > 0)
-+ selscrollback(oldstart - newstart);
-+
+
tclearregion(0, orig, term.col-1, orig+n-1);
tsetdirt(orig+n, term.bot);
-
-@@ -1100,6 +1527,8 @@ tscrollup(int orig, int n)
+@@ -1360,18 +1625,23 @@ tscrollup(int orig, int n)
void
selscroll(int orig, int n)
{
-+ if (sb.view_offset != 0)
-+ return;
+- if (view_offset != 0)
+- return;
++ int top, bot;
++
if (sel.ob.x == -1 || sel.alt != IS_SET(MODE_ALTSCREEN))
return;
-@@ -1720,6 +2149,12 @@ csihandle(void)
- break;
- case 2: /* all */
- tclearregion(0, 0, term.col-1, term.row-1);
-+ if (!IS_SET(MODE_ALTSCREEN))
-+ sb_reset_on_clear();
-+ break;
-+ case 3:
-+ if (!IS_SET(MODE_ALTSCREEN))
-+ sb_reset_on_clear();
- break;
- default:
- goto unknown;
-@@ -2109,7 +2544,7 @@ tdumpline(int n)
+- if (BETWEEN(sel.nb.y, orig, term.bot) != BETWEEN(sel.ne.y, orig, term.bot)) {
++ /* the scrolled screen region, in logical rows */
++ orig += sb.len;
++ top = sb.len + term.top;
++ bot = sb.len + term.bot;
++
++ if (BETWEEN(sel.nb.y, orig, bot) != BETWEEN(sel.ne.y, orig, bot)) {
+ selclear();
+- } else if (BETWEEN(sel.nb.y, orig, term.bot)) {
++ } else if (BETWEEN(sel.nb.y, orig, bot)) {
+ sel.ob.y += n;
+ sel.oe.y += n;
+- if (sel.ob.y < term.top || sel.ob.y > term.bot ||
+- sel.oe.y < term.top || sel.oe.y > term.bot) {
++ if (sel.ob.y < top || sel.ob.y > bot ||
++ sel.oe.y < top || sel.oe.y > bot) {
+ selclear();
+ } else {
+ selnormalize();
+@@ -1507,7 +1777,7 @@ tclearregion(int x1, int y1, int x2, int y2)
+ term.dirty[y] = 1;
+ for (x = x1; x <= x2; x++) {
+ gp = &term.line[y][x];
+- if (selected(x, y))
++ if (isselected(x, sb.len + y))
+ selclear();
+ gp->fg = term.c.attr.fg;
+ gp->bg = term.c.attr.bg;
+@@ -2379,7 +2649,7 @@ tdumpline(int n)
const Glyph *bp, *end;
bp = &term.line[n][0];
- end = &bp[MIN(tlinelen(n), term.col) - 1];
-+ end = &bp[MIN(tlinelen_render(n), term.col) - 1];
++ end = &bp[MIN(tlinelen(term.line[n]), term.col) - 1];
if (bp != end || bp->u != ' ') {
for ( ; bp <= end; ++bp)
tprinter(buf, utf8encode(bp->u, buf));
-@@ -2166,6 +2601,36 @@ tdeftran(char ascii)
- }
- }
-
-+static void
-+kscroll(const Arg *arg)
-+{
-+ uint64_t oldstart;
-+ uint64_t newstart;
-+
-+ oldstart = sb_view_start();
+@@ -2439,15 +2709,8 @@ tdeftran(char ascii)
+ static void
+ kscroll(const Arg *arg)
+ {
+- uint64_t oldstart;
+- uint64_t newstart;
+-
+- oldstart = sb_view_start();
+- view_offset += arg->i;
+- LIMIT(view_offset, 0, sb.len);
+- newstart = sb_view_start();
+-
+- selscrollback(oldstart - newstart);
+ sb.view_offset += arg->i;
+ LIMIT(sb.view_offset, 0, sb.len);
-+ newstart = sb_view_start();
-+
-+ selscrollback(oldstart - newstart);
-+ redraw();
-+}
-+
-+void
-+kscrolldown(const Arg *arg)
-+{
-+ Arg a;
-+
-+ a.i = -arg->i;
-+ kscroll(&a);
-+}
-+
-+void
-+kscrollup(const Arg *arg)
-+{
-+ kscroll(arg);
-+}
-+
- void
- tdectest(char c)
- {
-@@ -2572,83 +3037,138 @@ twrite(const char *buf, int buflen, int show_ctrl)
+ redraw();
+ }
+
+@@ -2793,7 +3056,7 @@ check_control_code:
+ */
+ return;
+ }
+- if (selected(term.c.x, term.c.y))
++ if (isselected(term.c.x, sb.len + term.c.y))
+ selclear();
+
+ gp = &term.line[term.c.y][term.c.x];
+@@ -2872,86 +3135,146 @@ twrite(const char *buf, int buflen, int show_ctrl)
void
tresize(int col, int row)
{
@@ -767,6 +915,9 @@ index 6f40e35..cf76c58 100644
- int mincol = MIN(col, term.col);
- int *bp;
- TCursor c;
+-
+- sb_clear();
+- sb_view_changed();
+ int old_row = term.row;
+ int old_col = term.col;
+ int save_end = 0; /* Track effective pushed height */
@@ -783,11 +934,14 @@ index 6f40e35..cf76c58 100644
return;
}
-- /*
+ /*
- * slide screen to keep cursor where we expect it -
- * tscrollup would work here, but we can optimize to
- * memmove because we're freeing the earlier lines
-- */
++ * Reflow and truncation move text around, and the alt screen
++ * is rebuilt from scratch. A pure height change keeps logical
++ * rows intact (lines go through scrollback and back).
+ */
- for (i = 0; i <= term.c.y - row; i++) {
- free(term.line[i]);
- free(term.alt[i]);
@@ -800,6 +954,9 @@ index 6f40e35..cf76c58 100644
- for (i += row; i < term.row; i++) {
- free(term.line[i]);
- free(term.alt[i]);
++ if (col != old_col || sel.alt)
++ selclear();
++
+ /* Operate on the currently visible screen buffer. */
+ if (is_alt) {
+ tmp = term.line;
@@ -955,94 +1112,102 @@ index 6f40e35..cf76c58 100644
}
void
-@@ -2662,12 +3182,13 @@ drawregion(int x1, int y1, int x2, int y2)
- {
- int y;
-
-+ Line line;
- for (y = y1; y < y2; y++) {
+@@ -2970,7 +3293,7 @@ drawregion(int x1, int y1, int x2, int y2)
if (!term.dirty[y])
continue;
--
term.dirty[y] = 0;
-- xdrawline(term.line[y], x1, y, x2);
+- line = getlineforrender(y);
+ line = renderline(y);
-+ xdrawline(line, x1, y, x2);
+ xdrawline(line, x1, y, x2);
}
}
-
-@@ -2688,10 +3209,12 @@ draw(void)
+@@ -2992,7 +3315,7 @@ draw(void)
cx--;
drawregion(0, 0, term.col, term.row);
-- xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
-- term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
-- term.ocx = cx;
-- term.ocy = term.c.y;
+- if (view_offset == 0) {
+ if (sb.view_offset == 0) {
-+ xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
-+ term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
-+ term.ocx = cx;
-+ term.ocy = term.c.y;
-+ }
- xfinishdraw();
- if (ocx != term.ocx || ocy != term.ocy)
- xximspot(term.ocx, term.ocy);
+ xdrawcursor(cx, term.c.y, term.line[term.c.y][cx],
+ term.ocx, term.ocy, term.line[term.ocy][term.ocx]);
+ term.ocx = cx;
diff --git a/st.h b/st.h
-index fd3b0d8..151d0c6 100644
+index 151d0c6..66f1436 100644
--- a/st.h
+++ b/st.h
-@@ -86,6 +86,7 @@ void printsel(const Arg *);
- void sendbreak(const Arg *);
- void toggleprinter(const Arg *);
-
-+int tisaltscreen(void);
- int tattrset(int);
- void tnew(int, int);
- void tresize(int, int);
-@@ -111,6 +112,9 @@ void *xmalloc(size_t);
- void *xrealloc(void *, size_t);
- char *xstrdup(const char *);
-
-+void kscrollup(const Arg *arg);
-+void kscrolldown(const Arg *arg);
-+
- /* config.h globals */
- extern char *utmp;
- extern char *scroll;
-@@ -124,3 +128,4 @@ extern unsigned int tabspaces;
- extern unsigned int defaultfg;
- extern unsigned int defaultbg;
- extern unsigned int defaultcs;
-+extern unsigned int scrollback_lines;
+@@ -103,6 +103,7 @@ void selclear(void);
+ void selinit(void);
+ void selstart(int, int, int);
+ void selextend(int, int, int, int);
++int selextendto(int, int, int);
+ int selected(int, int);
+ char *getsel(void);
+
diff --git a/x.c b/x.c
-index d73152b..75f3db1 100644
+index dfe416a..8091e6f 100644
--- a/x.c
+++ b/x.c
-@@ -472,6 +472,23 @@ bpress(XEvent *e)
- struct timespec now;
- int snap;
-
-+ if (btn == Button4 || btn == Button5) {
-+ Arg a;
-+ if (IS_SET(MODE_MOUSE) && !(e->xbutton.state & forcemousemod)) {
-+ mousereport(e);
-+ return;
-+ }
-+ if (!tisaltscreen()) {
-+ a.i = 1;
-+ if (btn == Button4) {
-+ kscrollup(&a);
-+ } else {
-+ kscrolldown(&a);
-+ }
-+ }
-+ return;
-+ }
+@@ -181,6 +181,7 @@ static void selnotify(XEvent *);
+ static void selclear_(XEvent *);
+ static void selrequest(XEvent *);
+ static void setsel(char *, Time);
++static int mouseseltype(XEvent *);
+ static void mousesel(XEvent *, int);
+ static void mousereport(XEvent *);
+ static char *kmap(KeySym, uint);
+@@ -344,19 +345,23 @@ evrow(XEvent *e)
+ return y / win.ch;
+ }
+
+-void
+-mousesel(XEvent *e, int done)
++int
++mouseseltype(XEvent *e)
+ {
+- int type, seltype = SEL_REGULAR;
++ int type;
+ uint state = e->xbutton.state & ~(Button1Mask | forcemousemod);
+
+ for (type = 1; type < LEN(selmasks); ++type) {
+- if (match(selmasks[type], state)) {
+- seltype = type;
+- break;
+- }
++ if (match(selmasks[type], state))
++ return type;
+ }
+- selextend(evcol(e), evrow(e), seltype, done);
++ return SEL_REGULAR;
++}
+
- if (1 <= btn && btn <= 11)
- buttons |= 1 << (btn-1);
++void
++mousesel(XEvent *e, int done)
++{
++ selextend(evcol(e), evrow(e), mouseseltype(e), done);
+ if (done)
+ setsel(getsel(), e->xbutton.time);
+ }
+@@ -485,6 +490,9 @@ bpress(XEvent *e)
+ } else {
+ kscrolldown(&a);
+ }
++ /* keep a selection being dragged under the pointer */
++ if (buttons & 1)
++ mousesel(e, 0);
+ }
+ return;
+ }
+@@ -501,6 +509,11 @@ bpress(XEvent *e)
+ return;
+ if (btn == Button1) {
++ /* shift+click extends the current selection */
++ if ((e->xbutton.state & ShiftMask) && !IS_SET(MODE_MOUSE) &&
++ selextendto(evcol(e), evrow(e), mouseseltype(e)))
++ return;
++
+ /*
+ * If the user clicks below predefined timeouts specific
+ * snapping behaviour is exposed.
--
-2.53.0
+2.56.0
