path: root/config/st-scrollback-0.7.diff

diff --git a/config.def.h b/config.def.h
index b41747f..eae969e 100644
--- a/config.def.h
+++ b/config.def.h
@@ -7,6 +7,7 @@
  */
 static char font[] = "Liberation Mono:pixelsize=12:antialias=true:autohint=true";
 static int borderpx = 2;
+#define histsize 2000
 
 /*
  * What program is execed by st depends of these precedence rules:
@@ -172,6 +173,8 @@ static Shortcut shortcuts[] = {
 	{ MODKEY|ShiftMask,     XK_C,           clipcopy,       {.i =  0} },
 	{ MODKEY|ShiftMask,     XK_V,           clippaste,      {.i =  0} },
 	{ MODKEY,               XK_Num_Lock,    numlock,        {.i =  0} },
+	{ ShiftMask,            XK_Page_Up,     kscrollup,      {.i = -1} },
+	{ ShiftMask,            XK_Page_Down,   kscrolldown,    {.i = -1} },
 };
 
 /*
diff --git a/st.c b/st.c
index 2594c65..233d301 100644
--- a/st.c
+++ b/st.c
@@ -86,6 +86,8 @@ char *argv0;
 #define TRUERED(x)		(((x) & 0xff0000) >> 8)
 #define TRUEGREEN(x)		(((x) & 0xff00))
 #define TRUEBLUE(x)		(((x) & 0xff) << 8)
+#define TLINE(y)		((y) < term.scr ? term.hist[((y) + term.histi - term.scr \
+				+ histsize + 1) % histsize] : term.line[(y) - term.scr])
 
 
 enum glyph_attribute {
@@ -228,26 +230,6 @@ typedef struct {
 	int narg;              /* nb of args */
 } STREscape;
 
-/* Internal representation of the screen */
-typedef struct {
-	int row;      /* nb row */
-	int col;      /* nb col */
-	Line *line;   /* screen */
-	Line *alt;    /* alternate screen */
-	int *dirty;  /* dirtyness of lines */
-	XftGlyphFontSpec *specbuf; /* font spec buffer used for rendering */
-	TCursor c;    /* cursor */
-	int top;      /* top    scroll limit */
-	int bot;      /* bottom scroll limit */
-	int mode;     /* terminal mode flags */
-	int esc;      /* escape state flags */
-	char trantbl[4]; /* charset table translation */
-	int charset;  /* current charset */
-	int icharset; /* selected charset for sequence */
-	int numlock; /* lock numbers in keyboard */
-	int *tabs;
-} Term;
-
 /* Purely graphic info */
 typedef struct {
 	Display *dpy;
@@ -327,6 +309,8 @@ typedef struct {
 /* function definitions used in config.h */
 static void clipcopy(const Arg *);
 static void clippaste(const Arg *);
+static void kscrolldown(const Arg *);
+static void kscrollup(const Arg *);
 static void numlock(const Arg *);
 static void selpaste(const Arg *);
 static void xzoom(const Arg *);
@@ -340,6 +324,29 @@ static void sendbreak(const Arg *);
 /* Config.h for applying patches and the configuration. */
 #include "config.h"
 
+/* Internal representation of the screen */
+typedef struct {
+	int row;      /* nb row */
+	int col;      /* nb col */
+	Line *line;   /* screen */
+	Line *alt;    /* alternate screen */
+	Line hist[histsize]; /* history buffer */
+	int histi;    /* history index */
+	int scr;      /* scroll back */
+	int *dirty;  /* dirtyness of lines */
+	XftGlyphFontSpec *specbuf; /* font spec buffer used for rendering */
+	TCursor c;    /* cursor */
+	int top;      /* top    scroll limit */
+	int bot;      /* bottom scroll limit */
+	int mode;     /* terminal mode flags */
+	int esc;      /* escape state flags */
+	char trantbl[4]; /* charset table translation */
+	int charset;  /* current charset */
+	int icharset; /* selected charset for sequence */
+	int numlock; /* lock numbers in keyboard */
+	int *tabs;
+} Term;
+
 /* Font structure */
 typedef struct {
 	int height;
@@ -399,8 +406,8 @@ static void tputtab(int);
 static void tputc(Rune);
 static void treset(void);
 static void tresize(int, int);
-static void tscrollup(int, int);
-static void tscrolldown(int, int);
+static void tscrollup(int, int, int);
+static void tscrolldown(int, int, int);
 static void tsetattr(int *, int);
 static void tsetchar(Rune, Glyph *, int, int);
 static void tsetscroll(int, int);
@@ -731,10 +738,10 @@ tlinelen(int y)
 {
 	int i = term.col;
 
-	if (term.line[y][i - 1].mode & ATTR_WRAP)
+	if (TLINE(y)[i - 1].mode & ATTR_WRAP)
 		return i;
 
-	while (i > 0 && term.line[y][i - 1].u == ' ')
+	while (i > 0 && TLINE(y)[i - 1].u == ' ')
 		--i;
 
 	return i;
@@ -796,7 +803,7 @@ 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 = &TLINE(*y)[*x];
 		prevdelim = ISDELIM(prevgp->u);
 		for (;;) {
 			newx = *x + direction;
@@ -811,14 +818,14 @@ selsnap(int *x, int *y, int direction)
 					yt = *y, xt = *x;
 				else
 					yt = newy, xt = newx;
-				if (!(term.line[yt][xt].mode & ATTR_WRAP))
+				if (!(TLINE(yt)[xt].mode & ATTR_WRAP))
 					break;
 			}
 
 			if (newx >= tlinelen(newy))
 				break;
 
-			gp = &term.line[newy][newx];
+			gp = &TLINE(newy)[newx];
 			delim = ISDELIM(gp->u);
 			if (!(gp->mode & ATTR_WDUMMY) && (delim != prevdelim
 					|| (delim && gp->u != prevgp->u)))
@@ -839,14 +846,14 @@ 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 (!(TLINE(*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 (!(TLINE(*y)[term.col-1].mode
 						& ATTR_WRAP)) {
 					break;
 				}
@@ -1012,13 +1019,13 @@ getsel(void)
 		}
 
 		if (sel.type == SEL_RECTANGULAR) {
-			gp = &term.line[y][sel.nb.x];
+			gp = &TLINE(y)[sel.nb.x];
 			lastx = sel.ne.x;
 		} else {
-			gp = &term.line[y][sel.nb.y == y ? sel.nb.x : 0];
+			gp = &TLINE(y)[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 = &TLINE(y)[MIN(lastx, linelen-1)];
 		while (last >= gp && last->u == ' ')
 			--last;
 
@@ -1490,6 +1497,9 @@ ttyread(void)
 	/* keep any uncomplete utf8 char for the next call */
 	memmove(buf, ptr, buflen);
 
+	if (term.scr > 0 && term.scr < histsize-1)
+		term.scr++;
+
 	return ret;
 }
 
@@ -1499,6 +1509,9 @@ ttywrite(const char *s, size_t n)
 	fd_set wfd, rfd;
 	ssize_t r;
 	size_t lim = 256;
+	Arg arg = (Arg){ .i = term.scr };
+
+	kscrolldown(&arg);
 
 	/*
 	 * Remember that we are using a pty, which might be a modem line.
@@ -1690,13 +1703,53 @@ tswapscreen(void)
 }
 
 void
-tscrolldown(int orig, int n)
+kscrolldown(const Arg* a)
+{
+	int n = a->i;
+
+	if (n < 0)
+		n = term.row + n;
+
+	if (n > term.scr)
+		n = term.scr;
+
+	if (term.scr > 0) {
+		term.scr -= n;
+		selscroll(0, -n);
+		tfulldirt();
+	}
+}
+
+void
+kscrollup(const Arg* a)
+{
+	int n = a->i;
+
+	if (n < 0)
+		n = term.row + n;
+
+	if (term.scr <= histsize - n) {
+		term.scr += n;
+		selscroll(0, n);
+		tfulldirt();
+	}
+}
+
+void
+tscrolldown(int orig, int n, int copyhist)
 {
 	int i;
 	Line temp;
 
 	LIMIT(n, 0, term.bot-orig+1);
 
+	if (copyhist) {
+		term.histi = (term.histi - 1 + histsize) % histsize;
+		temp = term.hist[term.histi];
+		term.hist[term.histi] = term.line[term.bot];
+		term.line[term.bot] = temp;
+	}
+
 	tsetdirt(orig, term.bot-n);
 	tclearregion(0, term.bot-n+1, term.col-1, term.bot);
 
@@ -1710,13 +1763,20 @@ tscrolldown(int orig, int n)
 }
 
 void
-tscrollup(int orig, int n)
+tscrollup(int orig, int n, int copyhist)
 {
 	int i;
 	Line temp;
 
 	LIMIT(n, 0, term.bot-orig+1);
 
+	if (copyhist) {
+		term.histi = (term.histi + 1) % histsize;
+		temp = term.hist[term.histi];
+		term.hist[term.histi] = term.line[orig];
+		term.line[orig] = temp;
+	}
+
 	tclearregion(0, orig, term.col-1, orig+n-1);
 	tsetdirt(orig+n, term.bot);
 
@@ -1765,7 +1825,7 @@ tnewline(int first_col)
 	int y = term.c.y;
 
 	if (y == term.bot) {
-		tscrollup(term.top, 1);
+		tscrollup(term.top, 1, 1);
 	} else {
 		y++;
 	}
@@ -1930,14 +1990,14 @@ void
 tinsertblankline(int n)
 {
 	if (BETWEEN(term.c.y, term.top, term.bot))
-		tscrolldown(term.c.y, n);
+		tscrolldown(term.c.y, n, 0);
 }
 
 void
 tdeleteline(int n)
 {
 	if (BETWEEN(term.c.y, term.top, term.bot))
-		tscrollup(term.c.y, n);
+		tscrollup(term.c.y, n, 0);
 }
 
 int32_t
@@ -2371,11 +2431,11 @@ csihandle(void)
 		break;
 	case 'S': /* SU -- Scroll <n> line up */
 		DEFAULT(csiescseq.arg[0], 1);
-		tscrollup(term.top, csiescseq.arg[0]);
+		tscrollup(term.top, csiescseq.arg[0], 0);
 		break;
 	case 'T': /* SD -- Scroll <n> line down */
 		DEFAULT(csiescseq.arg[0], 1);
-		tscrolldown(term.top, csiescseq.arg[0]);
+		tscrolldown(term.top, csiescseq.arg[0], 0);
 		break;
 	case 'L': /* IL -- Insert <n> blank lines */
 		DEFAULT(csiescseq.arg[0], 1);
@@ -2871,7 +2931,7 @@ eschandle(uchar ascii)
 		return 0;
 	case 'D': /* IND -- Linefeed */
 		if (term.c.y == term.bot) {
-			tscrollup(term.top, 1);
+			tscrollup(term.top, 1, 1);
 		} else {
 			tmoveto(term.c.x, term.c.y+1);
 		}
@@ -2884,7 +2944,7 @@ eschandle(uchar ascii)
 		break;
 	case 'M': /* RI -- Reverse index */
 		if (term.c.y == term.top) {
-			tscrolldown(term.top, 1);
+			tscrolldown(term.top, 1, 1);
 		} else {
 			tmoveto(term.c.x, term.c.y-1);
 		}
@@ -3047,7 +3107,7 @@ tputc(Rune u)
 void
 tresize(int col, int row)
 {
-	int i;
+	int i, j;
 	int minrow = MIN(row, term.row);
 	int mincol = MIN(col, term.col);
 	int *bp;
@@ -3087,6 +3147,14 @@ tresize(int col, int row)
 	term.dirty = xrealloc(term.dirty, row * sizeof(*term.dirty));
 	term.tabs = xrealloc(term.tabs, col * sizeof(*term.tabs));
 
+	for (i = 0; i < histsize; i++) {
+		term.hist[i] = xrealloc(term.hist[i], col * sizeof(Glyph));
+		for (j = mincol; j < col; j++) {
+			term.hist[i][j] = term.c.attr;
+			term.hist[i][j].u = ' ';
+		}
+	}
+
 	/* 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));
@@ -3976,11 +4044,11 @@ drawregion(int x1, int y1, int x2, int y2)
 		term.dirty[y] = 0;
 
 		specs = term.specbuf;
-		numspecs = xmakeglyphfontspecs(specs, &term.line[y][x1], x2 - x1, x1, y);
+		numspecs = xmakeglyphfontspecs(specs, &TLINE(y)[x1], x2 - x1, x1, y);
 
 		i = ox = 0;
 		for (x = x1; x < x2 && i < numspecs; x++) {
-			new = term.line[y][x];
+			new = TLINE(y)[x];
 			if (new.mode == ATTR_WDUMMY)
 				continue;
 			if (ena_sel && selected(x, y))
@@ -4000,7 +4068,8 @@ drawregion(int x1, int y1, int x2, int y2)
 		if (i > 0)
 			xdrawglyphfontspecs(specs, base, i, ox, y);
 	}
-	xdrawcursor();
+	if (term.scr == 0)
+		xdrawcursor();
 }
 
 void