Applying the CBT patch of Roberto Vargas. Thanks.

diff --git a/st.c b/st.c
index 5b98c6f..8cc0e1d 100644 (file)
--- a/st.c
+++ b/st.c
@@ -97,11 +97,11 @@ enum glyph_state {
 };
 
 enum term_mode {
-       MODE_WRAP        = 1,
+       MODE_WRAP       = 1,
        MODE_INSERT      = 2,
        MODE_APPKEYPAD   = 4,
        MODE_ALTSCREEN   = 8,
-       MODE_CRLF        = 16,
+       MODE_CRLF       = 16,
        MODE_MOUSEBTN    = 32,
        MODE_MOUSEMOTION = 64,
        MODE_MOUSE       = 32|64,
@@ -110,8 +110,8 @@ enum term_mode {
 
 enum escape_state {
        ESC_START      = 1,
-       ESC_CSI        = 2,
-       ESC_STR        = 4, /* DSC, OSC, PM, APC */
+       ESC_CSI = 2,
+       ESC_STR = 4, /* DSC, OSC, PM, APC */
        ESC_ALTCHARSET = 8,
        ESC_STR_END    = 16, /* a final string was encountered */
 };
@@ -152,21 +152,21 @@ typedef struct {
 /* ESC '[' [[ [<priv>] <arg> [;]] <mode>] */
 typedef struct {
        char buf[ESC_BUF_SIZ]; /* raw string */
-       int len;               /* raw string length */
+       int len;               /* raw string length */
        char priv;
        int arg[ESC_ARG_SIZ];
-       int narg;              /* nb of args */
+       int narg;             /* nb of args */
        char mode;
 } CSIEscape;
 
 /* STR Escape sequence structs */
 /* ESC type [[ [<priv>] <arg> [;]] <mode>] ESC '\' */
 typedef struct {
-       char type;             /* ESC type ... */
+       char type;           /* ESC type ... */
        char buf[STR_BUF_SIZ]; /* raw string */
-       int len;               /* raw string length */
+       int len;               /* raw string length */
        char *args[STR_ARG_SIZ];
-       int narg;              /* nb of args */
+       int narg;             /* nb of args */
 } STREscape;
 
 /* Internal representation of the screen */
@@ -262,7 +262,7 @@ static void tinsertblankline(int);
 static void tmoveto(int, int);
 static void tnew(int, int);
 static void tnewline(int);
-static void tputtab(void);
+static void tputtab(bool);
 static void tputc(char*);
 static void treset(void);
 static int tresize(int, int);
@@ -1243,7 +1243,7 @@ csihandle(void) {
        case 'I': /* CHT -- Cursor Forward Tabulation <n> tab stops */
                DEFAULT(csiescseq.arg[0], 1);
                while (csiescseq.arg[0]--)
-                       tputtab();
+                       tputtab(1);
                break;
        case 'J': /* ED -- Clear screen */
                sel.bx = -1;
@@ -1356,7 +1356,11 @@ csihandle(void) {
                DEFAULT(csiescseq.arg[0], 1);
                tdeletechar(csiescseq.arg[0]);
                break;
-       /* XXX: (CSI n Z) CBT -- Cursor Backward Tabulation <n> tab stops */
+       case 'Z': /* CBT -- Cursor Backward Tabulation <n> tab stops */
+               DEFAULT(csiescseq.arg[0], 1);
+               while (csiescseq.arg[0]--)
+                       tputtab(0);
+               break;
        case 'd': /* VPA -- Move to <row> */
                DEFAULT(csiescseq.arg[0], 1);
                tmoveto(term.c.x, csiescseq.arg[0]-1);
@@ -1528,11 +1532,20 @@ strreset(void) {
 }
 
 void
-tputtab(void) {
-       unsigned x;
+tputtab(bool forward) {
+       unsigned x = term.c.x;
 
-       for (x = term.c.x + 1; x < term.col && !term.tabs[x]; ++x)
-               /* nothing */ ;
+       if (forward) {
+               if (x == term.col)
+                       return;
+               for (++x; x < term.col && !term.tabs[x]; ++x)
+                       /* nothing */ ;
+       } else {
+               if (x == 0)
+                       return;
+               for (--x; x > 0 && !term.tabs[x]; --x)
+                       /* nothing */ ;
+       }
        tmoveto(x, term.c.y);
 }
 
@@ -1650,7 +1663,7 @@ tputc(char *c) {
                        sel.bx = -1;
                switch(ascii) {
                case '\t':
-                       tputtab();
+                       tputtab(1);
                        break;
                case '\b':
                        tmoveto(term.c.x-1, term.c.y);
@@ -1806,8 +1819,8 @@ void
 xclear(int x1, int y1, int x2, int y2) {
        XSetForeground(xw.dpy, dc.gc, dc.col[IS_SET(MODE_REVERSE) ? DefaultFG : DefaultBG]);
        XFillRectangle(xw.dpy, xw.buf, dc.gc,
-                      BORDER + x1 * xw.cw, BORDER + y1 * xw.ch,
-                      (x2-x1+1) * xw.cw, (y2-y1+1) * xw.ch);
+                      BORDER + x1 * xw.cw, BORDER + y1 * xw.ch,
+                      (x2-x1+1) * xw.cw, (y2-y1+1) * xw.ch);
 }
 
 void
@@ -1982,8 +1995,8 @@ xdraws(char *s, Glyph base, int x, int y, int charlen, int bytelen) {
 /* copy buffer pixmap to screen pixmap */
 void
 xcopy() {
-        XdbeSwapInfo swpinfo[1] = {{xw.win, XdbeCopied}};
-        XdbeSwapBuffers(xw.dpy, swpinfo, 1);
+       XdbeSwapInfo swpinfo[1] = {{xw.win, XdbeCopied}};
+       XdbeSwapBuffers(xw.dpy, swpinfo, 1);
 
 }
 
@@ -2080,8 +2093,8 @@ expose(XEvent *ev) {
        if(xw.state & WIN_REDRAW) {
                if(!e->count)
                        xw.state &= ~WIN_REDRAW;
-        }
-        xcopy();
+       }
+       xcopy();
 }
 
 void