ref: 4ee4f83e633f8e89fffc7ef133104dfde80bde32
parent: c19c2031e98f7f5844c177156847d29f3c47157d
author: qwx <qwx@sciops.net>
date: Mon Aug 5 18:16:38 EDT 2024
vt: skip over vertical line marks (from 9front) 4c6701041ec241bbb900883043790af2fd5e8152 by sigrid
--- /dev/null
+++ b/sys/src/cmd/vt/vt.c
@@ -1,0 +1,1033 @@
+/*
+ * Known bugs:
+ *
+ * 1. We don't handle cursor movement characters inside escape sequences.
+ * That is, ESC[2C moves two to the right, so ESC[2\bC is supposed to back
+ * up one and then move two to the right.
+ *
+ * 2. We don't handle tabstops past nelem(tabcol) columns.
+ *
+ * 3. We don't respect requests to do reverse video for the whole screen.
+ *
+ * 4. We ignore the ESC#n codes, so that we don't do double-width nor
+ * double-height lines, nor the ``fill the screen with E's'' confidence check.
+ *
+ * 5. Cursor key sequences aren't selected by keypad application mode.
+ *
+ * 6. "VT220" mode (-2) currently just switches the default cursor key
+ * functions (same as -a); it's still just a VT100 emulation.
+ *
+ * 7. VT52 mode and a few other rarely used features are not implemented.
+ */
+
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+
+#include "cons.h"
+
+#include <ctype.h>
+
+int wraparound = 1;
+int originrelative = 0;
+int bracketed = 0;
+
+int tabcol[200];
+char osc7cwd[WDIR];
+
+struct funckey ansifk[] = {+ { "up key", "\033[A", },+ { "down key", "\033[B", },+ { "left key", "\033[D", },+ { "right key", "\033[C", },+ { "F1", "\033OP", },+ { "F2", "\033OQ", },+ { "F3", "\033OR", },+ { "F4", "\033OS", },+ { "F5", "\033OT", },+ { "F6", "\033OU", },+ { "F7", "\033OV", },+ { "F8", "\033OW", },+ { "F9", "\033OX", },+ { "F10", "\033OY", },+ { "F11", "\033OZ", },+ { "F12", "\033O1", },+ { 0 },+};
+
+struct funckey ansiappfk[] = {+ { "up key", "\033OA", },+ { "down key", "\033OB", },+ { "left key", "\033OD", },+ { "right key", "\033OC", },+
+ { 0 },+};
+
+struct funckey vt220fk[] = {+ { "insert", "\033[2~", },+ { "delete", "\033[3~", },+ { "home", "\033[1~", },+ { "end", "\033[4~", },+ { "page up", "\033[5~", },+ { "page down", "\033[6~", },+
+ { "up key", "\033[A", },+ { "down key", "\033[B", },+ { "left key", "\033[D", },+ { "right key", "\033[C", },+
+ { "F1", "\033OP", },+ { "F2", "\033OQ", },+ { "F3", "\033OR", },+ { "F4", "\033OS", },+ { "F5", "\033[15~", },+ { "F6", "\033[17~", },+ { "F7", "\033[18~", },+ { "F8", "\033[19~", },+ { "F9", "\033[20~", },+ { "F10", "\033[21~", },+ { "F11", "\033[23~", },+ { "F12", "\033[24~", },+
+ { 0 },+};
+
+struct funckey xtermfk[] = {+ { "insert", "\033[2~", },+ { "delete", "\033[3~", },+ { "home", "\033OH", },+ { "end", "\033OF", },+ { "page up", "\033[5~", },+ { "page down", "\033[6~", },+
+ { "up key", "\033[A", },+ { "down key", "\033[B", },+ { "left key", "\033[D", },+ { "right key", "\033[C", },+
+ { "F1", "\033OP", },+ { "F2", "\033OQ", },+ { "F3", "\033OR", },+ { "F4", "\033OS", },+ { "F5", "\033[15~", },+ { "F6", "\033[17~", },+ { "F7", "\033[18~", },+ { "F8", "\033[19~", },+ { "F9", "\033[20~", },+ { "F10", "\033[21~", },+ { "F11", "\033[23~", },+ { "F12", "\033[24~", },+
+ { 0 },+};
+
+char gmap[256] = {+ ['_'] ' ', /* blank */
+ ['\\'] '*', /* diamond */
+ ['a'] 'X', /* checkerboard */
+ ['b'] '\t', /* HT */
+ ['c'] '\x0C', /* FF */
+ ['d'] '\r', /* CR */
+ ['e'] '\n', /* LF */
+ ['f'] 'o', /* degree */
+ ['g'] '+', /* plus/minus */
+ ['h'] '\n', /* NL, but close enough */
+ ['i'] '\v', /* VT */
+ ['j'] '+', /* lower right corner */
+ ['k'] '+', /* upper right corner */
+ ['l'] '+', /* upper left corner */
+ ['m'] '+', /* lower left corner */
+ ['n'] '+', /* crossing lines */
+ ['o'] '-', /* horiz line - scan 1 */
+ ['p'] '-', /* horiz line - scan 3 */
+ ['q'] '-', /* horiz line - scan 5 */
+ ['r'] '-', /* horiz line - scan 7 */
+ ['s'] '-', /* horiz line - scan 9 */
+ ['t'] '+', /* |- */
+ ['u'] '+', /* -| */
+ ['v'] '+', /* upside down T */
+ ['w'] '+', /* rightside up T */
+ ['x'] '|', /* vertical bar */
+ ['y'] '<', /* less/equal */
+ ['z'] '>', /* gtr/equal */
+ ['{'] 'p', /* pi */+ ['|'] '!', /* not equal */
+ ['}'] 'L', /* pound symbol */
+ ['~'] '.', /* centered dot: · */
+};
+
+static void setattr(int argc, int *argv);
+static void osc(void);
+
+void
+fixops(int *operand)
+{+ if(operand[0] < 1)
+ operand[0] = 1;
+}
+
+void
+emulate(void)
+{+ Rune buf[BUFS+1];
+ int i;
+ int n;
+ int c;
+ int operand[10];
+ int noperand;
+ int savex, savey, saveattr, saveisgraphics;
+ int isgraphics;
+ int g0set, g1set;
+
+ isgraphics = 0;
+ g0set = 'B'; /* US ASCII */
+ g1set = 'B'; /* US ASCII */
+ savex = savey = 0;
+ yscrmin = 0;
+ yscrmax = ymax;
+ saveattr = 0;
+ saveisgraphics = 0;
+ /* set initial tab stops to DEC-standard 8-column spacing */
+ for(c=0; (c+=8)<nelem(tabcol);)
+ tabcol[c] = 1;
+
+ for (;;) {+ if (y > ymax) {+ x = 0;
+ newline();
+ }
+ buf[0] = get_next_char();
+ buf[1] = '\0';
+ switch(buf[0]) {+
+ case '\000':
+ case '\001':
+ case '\002':
+ case '\003':
+ case '\004':
+ case '\005':
+ case '\006':
+ goto Default;
+
+ case '\007': /* bell */
+ ringbell();
+ break;
+
+ case '\010': /* backspace */
+ if (x > 0)
+ --x;
+ break;
+
+ case '\011': /* tab to next tab stop; if none, to right margin */
+ for(c=x+1; c<nelem(tabcol) && !tabcol[c]; c++)
+ ;
+ if(c < nelem(tabcol))
+ x = c;
+ else
+ x = xmax;
+ break;
+
+ case '\012': /* linefeed */
+ case '\013':
+ case '\014':
+ newline();
+ if (ttystate[cs->raw].nlcr)
+ x = 0;
+ break;
+
+ case '\015': /* carriage return */
+ x = 0;
+ if (ttystate[cs->raw].crnl)
+ newline();
+ break;
+
+ case '\016': /* SO: invoke G1 char set */
+ isgraphics = (isdigit(g1set));
+ break;
+ case '\017': /* SI: invoke G0 char set */
+ isgraphics = (isdigit(g0set));
+ break;
+
+ case '\020': /* DLE */
+ case '\021': /* DC1 */
+ case '\022': /* XON */
+ case '\023': /* DC3 */
+ case '\024': /* XOFF */
+ case '\025': /* NAK */
+ case '\026': /* SYN */
+ case '\027': /* ETB */
+ case '\030': /* CAN: cancel escape sequence, display checkerboard (not implemented) */
+ case '\031': /* EM */
+ case '\032': /* SUB: same as CAN */
+ goto Default;
+;
+ /* ESC, \033, is handled below */
+ case '\034': /* FS */
+ case '\035': /* GS */
+ case '\036': /* RS */
+ case '\037': /* US */
+ break;
+ case '\177': /* delete: ignored */
+ break;
+
+ case '\033':
+ switch(get_next_char()){+ /*
+ * 1 - graphic processor option on (no-op; not installed)
+ */
+ case '1':
+ break;
+
+ /*
+ * 2 - graphic processor option off (no-op; not installed)
+ */
+ case '2':
+ break;
+
+ /*
+ * 7 - save cursor position.
+ */
+ case '7':
+ savex = x;
+ savey = y;
+ saveattr = attr;
+ saveisgraphics = isgraphics;
+ break;
+
+ /*
+ * 8 - restore cursor position.
+ */
+ case '8':
+ x = savex;
+ y = savey;
+ attr = saveattr;
+ isgraphics = saveisgraphics;
+ break;
+
+ /*
+ * c - Reset terminal.
+ */
+ case 'c':
+ cursoron = 1;
+ ttystate[cs->raw].nlcr = 0;
+ break;
+
+ /*
+ * D - active position down a line, scroll if at bottom margin.
+ * (Original VT100 had a bug: tracked new-line/line-feed mode.)
+ */
+ case 'D':
+ if(++y > yscrmax) {+ y = yscrmax;
+ scroll(yscrmin+1, yscrmax+1, yscrmin, yscrmax);
+ }
+ break;
+
+ /*
+ * E - active position to start of next line, scroll if at bottom margin.
+ */
+ case 'E':
+ x = 0;
+ if(++y > yscrmax) {+ y = yscrmax;
+ scroll(yscrmin+1, yscrmax+1, yscrmin, yscrmax);
+ }
+ break;
+
+ /*
+ * H - set tab stop at current column.
+ * (This is cursor home in VT52 mode (not implemented).)
+ */
+ case 'H':
+ if(x < nelem(tabcol))
+ tabcol[x] = 1;
+ break;
+
+ /*
+ * M - active position up a line, scroll if at top margin..
+ */
+ case 'M':
+ if(--y < yscrmin) {+ y = yscrmin;
+ scroll(yscrmin, yscrmax, yscrmin+1, yscrmin);
+ }
+ break;
+
+ /*
+ * Z - identification. the terminal
+ * emulator will return the response
+ * code for a generic VT100.
+ */
+ case 'Z':
+ Ident:
+ sendnchars(7, "\033[?1;2c"); /* VT100 with AVO option */
+ break;
+
+ /*
+ * < - enter ANSI mode
+ */
+ case '<':
+ break;
+
+ /*
+ * > - set numeric keypad mode on (not implemented)
+ */
+ case '>':
+ break;
+
+ /*
+ * = - set numeric keypad mode off (not implemented)
+ */
+ case '=':
+ break;
+
+ /*
+ * # - Takes a one-digit argument
+ */
+ case '#':
+ switch(get_next_char()){+ case '3': /* Top half of double-height line */
+ case '4': /* Bottom half of double-height line */
+ case '5': /* Single-width single-height line */
+ case '6': /* Double-width line */
+ case '7': /* Screen print */
+ case '8': /* Fill screen with E's */
+ break;
+ }
+ break;
+
+ /*
+ * ( - switch G0 character set
+ */
+ case '(':+ g0set = get_next_char();
+ break;
+
+ /*
+ * - switch G1 character set
+ */
+ case ')':
+ g1set = get_next_char();
+ break;
+
+ /*
+ * Received left bracket.
+ */
+ case '[':
+ /*
+ * A semi-colon or ? delimits arguments.
+ */
+ memset(operand, 0, sizeof(operand));
+ operand[0] = number(buf, &i);
+ noperand = 1;
+ while(buf[0] == ';' || buf[0] == '?'){+ if(noperand < nelem(operand))
+ operand[noperand++] = number(buf, nil);
+ else
+ number(buf, nil);
+ }
+
+ /*
+ * do escape2 stuff
+ */
+ switch(buf[0]){+ /*
+ * c - same as ESC Z: what are you?
+ */
+ case 'c':
+ goto Ident;
+
+ /*
+ * g - various tabstop manipulation
+ */
+ case 'g':
+ switch(operand[0]){+ case 0: /* clear tab at current column */
+ if(x < nelem(tabcol))
+ tabcol[x] = 0;
+ break;
+ case 3: /* clear all tabs */
+ memset(tabcol, 0, sizeof tabcol);
+ break;
+ }
+ break;
+
+ /*
+ * l - clear various options.
+ */
+ case 'l':
+ if(noperand == 1){+ switch(operand[0]){ + case 20: /* set line feed mode */
+ ttystate[cs->raw].nlcr = 1;
+ break;
+ case 30: /* screen invisible (? not supported through VT220) */
+ break;
+ }
+ }else while(--noperand > 0){+ switch(operand[noperand]){+ case 1: /* set cursor keys to send ANSI functions: ESC [ A..D */
+ appfk = nil;
+ break;
+ case 2: /* set VT52 mode (not implemented) */
+ break;
+ case 3: /* set 80 columns */
+ setdim(-1, 80);
+ break;
+ case 4: /* set jump scrolling */
+ break;
+ case 5: /* set normal video on screen */
+ break;
+ case 6: /* set origin to absolute */
+ originrelative = 0;
+ x = y = 0;
+ break;
+ case 7: /* reset auto-wrap mode */
+ wraparound = 0;
+ break;
+ case 8: /* reset auto-repeat mode */
+ break;
+ case 9: /* reset interlacing mode */
+ break;
+ case 25: /* text cursor off (VT220) */
+ cursoron = 0;
+ break;
+ case 2004: /* bracketed paste mode off */
+ bracketed = 0;
+ break;
+ }
+ }
+ break;
+
+ /*
+ * s - some dec private stuff. actually [ ? num s, but we can't detect it.
+ */
+ case 's':
+ break;
+
+ /*
+ * h - set various options.
+ */
+ case 'h':
+ if(noperand == 1){+ switch(operand[0]){+ default:
+ break;
+ case 20: /* set newline mode */
+ ttystate[cs->raw].nlcr = 0;
+ break;
+ case 30: /* screen visible (? not supported through VT220) */
+ break;
+ }
+ }else while(--noperand > 0){+ switch(operand[noperand]){+ default:
+ break;
+ case 1: /* set cursor keys to send application function: ESC O A..D */
+ appfk = ansiappfk;
+ break;
+ case 2: /* set ANSI */
+ break;
+ case 3: /* set 132 columns */
+ setdim(-1, 132);
+ break;
+ case 4: /* set smooth scrolling */
+ break;
+ case 5: /* set screen to reverse video (not implemented) */
+ break;
+ case 6: /* set origin to relative */
+ originrelative = 1;
+ x = 0;
+ y = yscrmin;
+ break;
+ case 7: /* set auto-wrap mode */
+ wraparound = 1;
+ break;
+ case 8: /* set auto-repeat mode */
+ break;
+ case 9: /* set interlacing mode */
+ break;
+ case 25: /* text cursor on (VT220) */
+ cursoron = 1;
+ break;
+ case 2004: /* bracketed paste mode on */
+ bracketed = 1;
+ break;
+ }
+ }
+ break;
+
+ /*
+ * m - change character attrs.
+ */
+ case 'm':
+ setattr(noperand, operand);
+ break;
+
+ /*
+ * n - request various reports
+ */
+ case 'n':
+ switch(operand[0]){+ case 5: /* status */
+ sendnchars(4, "\033[0n"); /* terminal ok */
+ break;
+ case 6: /* cursor position */
+ sendnchars(sprint((char*)buf, "\033[%d;%dR",
+ originrelative ? y+1 - yscrmin : y+1, x+1), (char*)buf);
+ break;
+ }
+ break;
+
+ /*
+ * q - turn on list of LEDs; turn off others.
+ */
+ case 'q':
+ break;
+
+ /*
+ * r - change scrolling region. operand[0] is
+ * min scrolling region and operand[1] is max
+ * scrolling region.
+ */
+ case 'r':
+ yscrmin = 0;
+ yscrmax = ymax;
+ switch(noperand){+ case 2:
+ yscrmax = operand[1]-1;
+ if(yscrmax > ymax)
+ yscrmax = ymax;
+ case 1:
+ yscrmin = operand[0]-1;
+ if(yscrmin < 0)
+ yscrmin = 0;
+ }
+ x = 0;
+ y = yscrmin;
+ break;
+
+ /*
+ * x - report terminal parameters
+ */
+ case 'x':
+ sendnchars(20, "\033[3;1;1;120;120;1;0x");
+ break;
+
+ /*
+ * y - invoke confidence test
+ */
+ case 'y':
+ break;
+
+ /*
+ * z - line spacing
+ */
+ case 'z':
+ break;
+
+ /*
+ * A - cursor up.
+ */
+ case 'e':
+ case 'A':
+ fixops(operand);
+ y -= operand[0];
+ if(y < yscrmin)
+ y = yscrmin;
+ olines -= operand[0];
+ if(olines < 0)
+ olines = 0;
+ break;
+
+ /*
+ * B - cursor down
+ */
+ case 'B':
+ fixops(operand);
+ y += operand[0];
+ if(y > yscrmax)
+ y=yscrmax;
+ break;
+
+ /*
+ * C - cursor right
+ */
+ case 'a':
+ case 'C':
+ fixops(operand);
+ x += operand[0];
+ /*
+ * VT-100-UG says not to go past the
+ * right margin.
+ */
+ if(x > xmax)
+ x = xmax;
+ break;
+
+ /*
+ * D - cursor left
+ */
+ case 'D':
+ fixops(operand);
+ x -= operand[0];
+ if(x < 0)
+ x = 0;
+ break;
+
+ /*
+ * G - cursor to column
+ */
+ case '\'':
+ case 'G':
+ fixops(operand);
+ x = operand[0] - 1;
+ if(x > xmax)
+ x = xmax;
+ break;
+
+ /*
+ * H and f - cursor motion. operand[0] is row and
+ * operand[1] is column, origin 1.
+ */
+ case 'H':
+ case 'f':
+ fixops(operand+1);
+ x = operand[1] - 1;
+ if(x > xmax)
+ x = xmax;
+
+ /* fallthrough */
+
+ /*
+ * d - cursor to line n (xterm)
+ */
+ case 'd':
+ fixops(operand);
+ y = operand[0] - 1;
+ if(originrelative){+ y += yscrmin;
+ if(y > yscrmax)
+ y = yscrmax;
+ }else{+ if(y > ymax)
+ y = ymax;
+ }
+ break;
+
+ /*
+ * J - clear some or all of the display.
+ */
+ case 'J':
+ switch (operand[0]) {+ /*
+ * operand 2: whole screen.
+ */
+ case 2:
+ clear(0, 0, xmax+1, ymax+1);
+ break;
+ /*
+ * operand 1: start of screen to active position, inclusive.
+ */
+ case 1:
+ clear(0, 0, xmax+1, y);
+ clear(0, y, x+1, y+1);
+ break;
+ /*
+ * Default: active position to end of screen, inclusive.
+ */
+ default:
+ clear(x, y, xmax+1, y+1);
+ clear(0, y+1, xmax+1, ymax+1);
+ break;
+ }
+ break;
+
+ /*
+ * K - clear some or all of the line.
+ */
+ case 'K':
+ switch (operand[0]) {+ /*
+ * operand 2: whole line.
+ */
+ case 2:
+ clear(0, y, xmax+1, y+1);
+ break;
+ /*
+ * operand 1: start of line to active position, inclusive.
+ */
+ case 1:
+ clear(0, y, x+1, y+1);
+ break;
+ /*
+ * Default: active position to end of line, inclusive.
+ */
+ default:
+ clear(x, y, xmax+1, y+1);
+ break;
+ }
+ break;
+
+ /*
+ * P - delete character(s) from right of cursor (xterm)
+ */
+ case 'P':
+ fixops(operand);
+ i = x + operand[0];
+ shift(x, y, i, xmax+1 - i);
+ clear(xmax-operand[0], y, xmax+1, y+1);
+ break;
+
+ /*
+ * @ - insert blank(s) to right of cursor (xterm)
+ */
+ case '@':
+ fixops(operand);
+ i = x + operand[0];
+ shift(i, y, x, xmax+1 - i);
+ clear(x, y, i, y+1);
+ break;
+
+
+ /*
+ * X - erase character(s) at cursor and to the right (xterm)
+ */
+ case 'X':
+ fixops(operand);
+ i = x + operand[0];
+ clear(x, y, i, y+1);
+ break;
+
+ /*
+ * L - insert a line at cursor position (VT102 and later)
+ */
+ case 'L':
+ fixops(operand);
+ for(i = 0; i < operand[0]; ++i)
+ scroll(y, yscrmax, y+1, y);
+ break;
+
+ /*
+ * M - delete a line at cursor position (VT102 and later)
+ */
+ case 'M':
+ fixops(operand);
+ for(i = 0; i < operand[0]; ++i)
+ scroll(y+1, yscrmax+1, y, yscrmax);
+ break;
+
+ /*
+ * S,T - scroll up/down (xterm)
+ */
+ case 'T':
+ fixops(operand);
+ for(i = 0; i < operand[0]; ++i)
+ scroll(yscrmin, yscrmax, yscrmin+1, yscrmin);
+ break;
+
+ case 'S':
+ fixops(operand);
+ for(i = 0; i < operand[0]; ++i)
+ scroll(yscrmin+1, yscrmax+1, yscrmin, yscrmin);
+ break;
+
+ case '=': /* ? not supported through VT220 */
+ number(buf, nil);
+ switch(buf[0]) {+ case 'h':
+ case 'l':
+ break;
+ }
+ break;
+ case '>': /* Set/reset key modifier options (XTMODKEYS), xterm. */
+ number(buf, nil);
+ if(buf[0] != 'm' && buf[0] != 'M')
+ number(buf, nil);
+ break;
+ }
+
+ break;
+
+ /*
+ * Collapse multiple '\033' to one.
+ */
+ case '\033':
+ peekc = '\033';
+ break;
+
+ /* OSC escape */
+ case ']':
+ osc();
+ break;
+ }
+ break;
+
+ default: /* ordinary char */
+Default:
+ if(isgraphics && buf[0] < nelem(gmap) && gmap[buf[0]])
+ buf[0] = gmap[buf[0]];
+
+ /* line wrap */
+ if (x > xmax){+ if(wraparound){+ newline();
+ x = 0;
+ }else{+ continue;
+ }
+ }
+ n = 1;
+ c = 0;
+ while (!cs->raw && host_avail() && x+n<=xmax && n<BUFS
+ && (c = get_next_char())>=' ' && c<'\177') {+ buf[n++] = c;
+ c = 0;
+ }
+ buf[n] = 0;
+ drawstring(buf, n);
+ x += n;
+ peekc = c;
+ break;
+ }
+ }
+}
+
+static void
+setattr(int argc, int *argv)
+{+ int i;
+
+ for(i=0; i<argc; i++) {+ switch(argv[i]) {+ case 0:
+ attr = defattr;
+ break;
+ case 1:
+ attr |= THighIntensity;
+ break;
+ case 4:
+ attr |= TUnderline;
+ break;
+ case 5:
+ attr |= TBlink;
+ break;
+ case 7:
+ attr |= TReverse;
+ break;
+ case 8:
+ attr |= TInvisible;
+ break;
+ case 22:
+ attr &= ~THighIntensity;
+ break;
+ case 24:
+ attr &= ~TUnderline;
+ break;
+ case 25:
+ attr &= ~TBlink;
+ break;
+ case 27:
+ attr &= ~TReverse;
+ break;
+ case 28:
+ attr &= ~TInvisible;
+ break;
+ case 30: /* black */
+ case 31: /* red */
+ case 32: /* green */
+ case 33: /* brown */
+ case 34: /* blue */
+ case 35: /* purple */
+ case 36: /* cyan */
+ case 37: /* white */
+ attr = (attr & ~0xF000) | 0x1000 | (argv[i]-30)<<13;
+ break;
+ case 39: /* default */
+ attr &= ~0xF000;
+ break;
+ case 40: /* black */
+ case 41: /* red */
+ case 42: /* green */
+ case 43: /* brown */
+ case 44: /* blue */
+ case 45: /* purple */
+ case 46: /* cyan */
+ case 47: /* white */
+ attr = (attr & ~0x0F00) | 0x0100 | (argv[i]-40)<<9;
+ break;
+ case 49: /* default */
+ attr &= ~0x0F00;
+ break;
+ }
+ }
+}
+
+static int
+hexnib(char c)
+{+ if(c >= 'a')
+ return c - 'a' + 10;
+ if(c >= 'A')
+ return c - 'A' + 10;
+ return c - '0';
+}
+
+// handle ESC], Operating System Command
+static void
+osc(void)
+{+ Rune ch, buf[BUFS+1];
+ int fd, osc, got, i;
+ char *o, *s;
+ osc = number(&ch, &got);
+
+ if(got) {+ switch(osc) {+ case 0:
+ case 1:
+ case 2: /* set title */
+ i = 0;
+
+ while((ch = get_next_char()) != '\a') {+ if(i < nelem(buf) - 1) {+ buf[i++] = ch;
+ }
+ }
+ buf[i] = 0;
+ if((fd = open("/dev/label", OWRITE)) >= 0) {+ fprint(fd, "%S", buf);
+ close(fd);
+ }
+ break;
+
+ case 7: /* set pwd */
+ i = 0;
+
+ while((ch = get_next_char()) != '\033'){+ if(i < sizeof(osc7cwd)-UTFmax-1)
+ i += runetochar(osc7cwd+i, &ch);
+ }
+ get_next_char();
+ osc7cwd[i] = 0;
+
+ /* file://hostname/path → /n/hostname/path */
+ if(strncmp(osc7cwd, "file://", 7) == 0){+ osc7cwd[0] = '/';
+ osc7cwd[1] = 'n';
+ o = osc7cwd+2;
+ s = osc7cwd+6;
+ while(*s){+ if(*s == '%' && s[1] != 0 && s[2] != 0){+ *o++ = hexnib(s[1])<<4 | hexnib(s[2]);
+ s += 3;
+ }else
+ *o++ = *s++;
+ }
+ *o = 0;
+ }
+ break;
+ }
+ }
+}