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-rw-r--r--bterm.h431
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diff --git a/bterm.h b/bterm.h
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+++ b/bterm.h
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+/*
+ * bterm.h
+ * Copyright 2019 Bruce Hill
+ * Released under the MIT License
+ *
+ * Definitions of some basic terminal stuff, like reading keys
+ * and some terminal escape sequences.
+ */
+
+#ifndef FILE__BTERM_H
+#define FILE__BTERM_H
+
+#include <poll.h>
+#include <stdio.h>
+
+#define KEY_F1 (0xFFFF-0)
+#define KEY_F2 (0xFFFF-1)
+#define KEY_F3 (0xFFFF-2)
+#define KEY_F4 (0xFFFF-3)
+#define KEY_F5 (0xFFFF-4)
+#define KEY_F6 (0xFFFF-5)
+#define KEY_F7 (0xFFFF-6)
+#define KEY_F8 (0xFFFF-7)
+#define KEY_F9 (0xFFFF-8)
+#define KEY_F10 (0xFFFF-9)
+#define KEY_F11 (0xFFFF-10)
+#define KEY_F12 (0xFFFF-11)
+#define KEY_INSERT (0xFFFF-12)
+#define KEY_DELETE (0xFFFF-13)
+#define KEY_HOME (0xFFFF-14)
+#define KEY_END (0xFFFF-15)
+#define KEY_PGUP (0xFFFF-16)
+#define KEY_PGDN (0xFFFF-17)
+#define KEY_ARROW_UP (0xFFFF-18)
+#define KEY_ARROW_DOWN (0xFFFF-19)
+#define KEY_ARROW_LEFT (0xFFFF-20)
+#define KEY_ARROW_RIGHT (0xFFFF-21)
+#define KEY_MOUSE_LEFT (0xFFFF-22)
+#define KEY_MOUSE_RIGHT (0xFFFF-23)
+#define KEY_MOUSE_MIDDLE (0xFFFF-24)
+#define KEY_MOUSE_RELEASE (0xFFFF-25)
+#define KEY_MOUSE_WHEEL_UP (0xFFFF-26)
+#define KEY_MOUSE_WHEEL_DOWN (0xFFFF-27)
+#define KEY_MOUSE_DOUBLE_LEFT (0xFFFF-28)
+
+/* These are all ASCII code points below SPACE character and a BACKSPACE key. */
+#define KEY_CTRL_TILDE 0x00
+#define KEY_CTRL_2 0x00 /* clash with 'CTRL_TILDE' */
+#define KEY_CTRL_A 0x01
+#define KEY_CTRL_B 0x02
+#define KEY_CTRL_C 0x03
+#define KEY_CTRL_D 0x04
+#define KEY_CTRL_E 0x05
+#define KEY_CTRL_F 0x06
+#define KEY_CTRL_G 0x07
+#define KEY_BACKSPACE 0x08
+#define KEY_CTRL_H 0x08 /* clash with 'CTRL_BACKSPACE' */
+#define KEY_TAB 0x09
+#define KEY_CTRL_I 0x09 /* clash with 'TAB' */
+#define KEY_CTRL_J 0x0A
+#define KEY_CTRL_K 0x0B
+#define KEY_CTRL_L 0x0C
+#define KEY_ENTER 0x0D
+#define KEY_CTRL_M 0x0D /* clash with 'ENTER' */
+#define KEY_CTRL_N 0x0E
+#define KEY_CTRL_O 0x0F
+#define KEY_CTRL_P 0x10
+#define KEY_CTRL_Q 0x11
+#define KEY_CTRL_R 0x12
+#define KEY_CTRL_S 0x13
+#define KEY_CTRL_T 0x14
+#define KEY_CTRL_U 0x15
+#define KEY_CTRL_V 0x16
+#define KEY_CTRL_W 0x17
+#define KEY_CTRL_X 0x18
+#define KEY_CTRL_Y 0x19
+#define KEY_CTRL_Z 0x1A
+#define KEY_ESC 0x1B
+#define KEY_CTRL_LSQ_BRACKET 0x1B /* clash with 'ESC' */
+#define KEY_CTRL_3 0x1B /* clash with 'ESC' */
+#define KEY_CTRL_4 0x1C
+#define KEY_CTRL_BACKSLASH 0x1C /* clash with 'CTRL_4' */
+#define KEY_CTRL_5 0x1D
+#define KEY_CTRL_RSQ_BRACKET 0x1D /* clash with 'CTRL_5' */
+#define KEY_CTRL_6 0x1E
+#define KEY_CTRL_7 0x1F
+#define KEY_CTRL_SLASH 0x1F /* clash with 'CTRL_7' */
+#define KEY_CTRL_UNDERSCORE 0x1F /* clash with 'CTRL_7' */
+#define KEY_SPACE 0x20
+#define KEY_BACKSPACE2 0x7F
+#define KEY_CTRL_8 0x7F /* clash with 'BACKSPACE2' */
+
+
+// Terminal escape sequences:
+#define CSI "\033["
+#define T_WRAP "7"
+#define T_SHOW_CURSOR "25"
+#define T_MOUSE_XY "1000"
+#define T_MOUSE_CELL "1002"
+#define T_MOUSE_SGR "1006"
+#define T_ALT_SCREEN "1049"
+#define T_ON(opt) CSI "?" opt "h"
+#define T_OFF(opt) CSI "?" opt "l"
+
+#define move_cursor(f, x, y) fprintf((f), CSI "%d;%dH", (int)(y)+1, (int)(x)+1)
+
+
+#define ESC_DELAY 10
+
+int bgetkey(FILE *in, int *mouse_x, int *mouse_y, int timeout);
+const char *bkeyname(int key);
+char *breadline(FILE *in, FILE *out, const char *prompt, const char *initial);
+
+static inline int nextchar(int fd, int timeout)
+{
+ char c;
+ struct pollfd pfd = {fd, POLLIN, 0};
+ if (poll(&pfd, 1, timeout) > 0)
+ return read(fd, &c, 1) == 1 ? c : -1;
+ return -1;
+}
+
+/**
+ * Get one key of input from the given file. Returns -1 on failure.
+ *
+ * If mouse_x or mouse_y are non-null and a mouse event occurs, they will be
+ * set to the position of the mouse (0-indexed).
+ */
+int bgetkey(FILE *in, int *mouse_x, int *mouse_y, int timeout)
+{
+ int fd = fileno(in);
+ int numcode = 0, super = 0;
+ int c = nextchar(fd, timeout);
+ if (c == '\x1b')
+ goto escape;
+
+ return c;
+
+ escape:
+ c = nextchar(fd, ESC_DELAY);
+ // Actual escape key:
+ if (c < 0)
+ return KEY_ESC;
+
+ switch (c) {
+ case '\x1b': ++super; goto escape;
+ case '[': goto CSI_start;
+ case 'P': goto DCS;
+ case 'O': goto SS3;
+ default: return -1;
+ }
+
+ CSI_start:
+ c = nextchar(fd, ESC_DELAY);
+ if (c == -1)
+ return -1;
+
+ switch (c) {
+ case 'A': return KEY_ARROW_UP;
+ case 'B': return KEY_ARROW_DOWN;
+ case 'C': return KEY_ARROW_RIGHT;
+ case 'D': return KEY_ARROW_LEFT;
+ case 'F': return KEY_END;
+ case 'H': return KEY_HOME;
+ case '~':
+ switch (numcode) {
+ case 3: return KEY_DELETE;
+ case 5: return KEY_PGUP;
+ case 6: return KEY_PGDN;
+ case 15: return KEY_F5;
+ case 17: return KEY_F6;
+ case 18: return KEY_F7;
+ case 19: return KEY_F8;
+ case 20: return KEY_F9;
+ case 21: return KEY_F10;
+ case 23: return KEY_F11;
+ case 24: return KEY_F12;
+ }
+ return -1;
+ case '<': { // Mouse clicks
+ int buttons = 0, x = 0, y = 0;
+ char buf;
+ while (read(fd, &buf, 1) == 1 && '0' <= buf && buf <= '9')
+ buttons = buttons * 10 + (buf - '0');
+ if (buf != ';') return -1;
+ while (read(fd, &buf, 1) == 1 && '0' <= buf && buf <= '9')
+ x = x * 10 + (buf - '0');
+ if (buf != ';') return -1;
+ while (read(fd, &buf, 1) == 1 && '0' <= buf && buf <= '9')
+ y = y * 10 + (buf - '0');
+ if (buf != 'm' && buf != 'M') return -1;
+
+ if (mouse_x) *mouse_x = x - 1;
+ if (mouse_y) *mouse_y = y - 1;
+
+ if (buf == 'm')
+ return KEY_MOUSE_RELEASE;
+ switch (buttons) {
+ case 64: return KEY_MOUSE_WHEEL_UP;
+ case 65: return KEY_MOUSE_WHEEL_DOWN;
+ case 0: return KEY_MOUSE_LEFT;
+ case 1: return KEY_MOUSE_RIGHT;
+ case 2: return KEY_MOUSE_MIDDLE;
+ default: return -1;
+ }
+ break;
+ }
+ default:
+ if ('0' <= c && c <= '9') {
+ // Ps prefix
+ numcode = 10*numcode + (c - '0');
+ goto CSI_start;
+ }
+ }
+ return -1;
+
+ DCS:
+ return -1;
+
+ SS3:
+ switch (nextchar(fd, ESC_DELAY)) {
+ case 'P': return KEY_F1;
+ case 'Q': return KEY_F2;
+ case 'R': return KEY_F3;
+ case 'S': return KEY_F4;
+ default: break;
+ }
+ return -1;
+}
+
+/**
+ * Return the name of a key, if one exists and is different from the key itself
+ * (i.e. bkeyname('c') == NULL, bkeyname(' ') == "Space")
+ */
+const char *bkeyname(int key)
+{
+ // TODO: currently only the keys I'm using are named
+ switch (key) {
+ case KEY_F1: return "F1";
+ case KEY_F2: return "F2";
+ case KEY_F3: return "F3";
+ case KEY_F4: return "F4";
+ case KEY_F5: return "F5";
+ case KEY_F6: return "F6";
+ case KEY_F7: return "F7";
+ case KEY_F8: return "F8";
+ case KEY_F9: return "F9";
+ case KEY_F10: return "F10";
+ case KEY_F11: return "F11";
+ case KEY_F12: return "F12";
+ case KEY_INSERT: return "Insert";
+ case KEY_DELETE: return "Delete";
+ case KEY_HOME: return "Home";
+ case KEY_END: return "End";
+ case KEY_PGUP: return "PgUp";
+ case KEY_PGDN: return "PgDn";
+ case KEY_ARROW_UP: return "Up";
+ case KEY_ARROW_DOWN: return "Down";
+ case KEY_ARROW_LEFT: return "Left";
+ case KEY_ARROW_RIGHT: return "Right";
+ case KEY_MOUSE_LEFT: return "Left click";
+ case KEY_MOUSE_RIGHT: return "Right click";
+ case KEY_MOUSE_MIDDLE: return "Middle click";
+ case KEY_MOUSE_RELEASE: return "Mouse release";
+ case KEY_MOUSE_WHEEL_UP: return "Mouse wheel up";
+ case KEY_MOUSE_WHEEL_DOWN: return "Mouse wheel down";
+ case KEY_MOUSE_DOUBLE_LEFT: return "Mouse double left";
+ case KEY_CTRL_TILDE: return "Ctrl-[2~]";
+ case KEY_CTRL_A: return "Ctrl-a";
+ case KEY_CTRL_B: return "Ctrl-b";
+ case KEY_CTRL_C: return "Ctrl-c";
+ case KEY_CTRL_D: return "Ctrl-d";
+ case KEY_CTRL_E: return "Ctrl-e";
+ case KEY_CTRL_F: return "Ctrl-f";
+ case KEY_CTRL_G: return "Ctrl-g";
+ case KEY_BACKSPACE: return "Backspace";
+ case KEY_TAB: return "Tab";
+ case KEY_CTRL_J: return "Ctrl-j";
+ case KEY_CTRL_K: return "Ctrl-k";
+ case KEY_CTRL_L: return "Ctrl-l";
+ case KEY_ENTER: return "Enter";
+ case KEY_CTRL_N: return "Ctrl-n";
+ case KEY_CTRL_O: return "Ctrl-o";
+ case KEY_CTRL_P: return "Ctrl-p";
+ case KEY_CTRL_Q: return "Ctrl-q";
+ case KEY_CTRL_R: return "Ctrl-r";
+ case KEY_CTRL_S: return "Ctrl-s";
+ case KEY_CTRL_T: return "Ctrl-t";
+ case KEY_CTRL_U: return "Ctrl-u";
+ case KEY_CTRL_V: return "Ctrl-v";
+ case KEY_CTRL_W: return "Ctrl-w";
+ case KEY_CTRL_X: return "Ctrl-x";
+ case KEY_CTRL_Y: return "Ctrl-y";
+ case KEY_CTRL_Z: return "Ctrl-z";
+ case KEY_ESC: return "Esc";
+ case KEY_CTRL_BACKSLASH: return "Ctrl-[4\\]";
+ case KEY_CTRL_RSQ_BRACKET: return "Ctrl-[5]]";
+ case KEY_CTRL_6: return "Ctrl-6";
+ case KEY_CTRL_SLASH: return "Ctrl-[7/_]";
+ case KEY_SPACE: return "Space";
+ case KEY_BACKSPACE2: return "Backspace";
+ }
+ return NULL;
+}
+
+/**
+ * A basic readline implementation. No history, but all the normal editing
+ * key bindings like Ctrl-U to clear to the beginning of the line, backspace,
+ * arrow keys, etc.
+ *
+ * Takes an input file and output file, and an optional prompt and returns
+ * a malloc'd string containing the user's input or NULL if an error occurred
+ * or if the user hit Escape or Ctrl-c.
+ */
+char *breadline(FILE *in, FILE *out, const char *prompt, const char *initial)
+{
+ size_t cap = initial ? strlen(initial) + 100 : 100;
+ char *buf = calloc(cap, 1);
+ if (!buf) return NULL;
+ int i = 0, len = 0;
+ if (prompt) {
+ fputs("\033[1G\033[K\033[37;1m", out);
+ fputs(prompt, out);
+ fputs("\033[0m", out);
+ }
+ if (initial) {
+ strcpy(buf, initial);
+ len = (int)strlen(initial);
+ i = len;
+ fputs(initial, out);
+ }
+ // Show cursor and set to blinking line:
+ fputs("\033[?25h\033[5 q", out);
+ while (1) {
+ fflush(out);
+ int key = bgetkey(in, NULL, NULL, -1);
+ switch (key) {
+ case -1: case -2: case -3: continue;
+ case '\r':
+ // TODO: support backslash-enter
+ goto finished;
+ case KEY_CTRL_C: case KEY_ESC:
+ free(buf);
+ buf = NULL;
+ goto finished;
+ case KEY_CTRL_A:
+ if (i > 0) {
+ fprintf(out, "\033[%dD", i);
+ i = 0;
+ }
+ break;
+ case KEY_CTRL_E:
+ if (i < len) {
+ fprintf(out, "\033[%dC", len-i);
+ i = len;
+ }
+ break;
+ case KEY_CTRL_U: {
+ int to_clear = i;
+ if (to_clear) {
+ memmove(buf, buf+i, len-i);
+ buf[len -= i] = 0;
+ i = 0;
+ fprintf(out, "\033[%dD\033[K", to_clear);
+ if (len > 0)
+ fprintf(out, "%s\033[%dD", buf, len);
+ }
+ break;
+ }
+ case KEY_CTRL_K:
+ if (i < len) {
+ buf[len = i] = 0;
+ fputs("\033[K", out);
+ }
+ break;
+ case KEY_BACKSPACE: case KEY_BACKSPACE2:
+ if (i > 0) {
+ memmove(buf+i, buf+i+1, len-i);
+ --i;
+ buf[--len] = 0;
+ if (i == len) fputs("\033[D \033[D", out);
+ else fprintf(out, "\033[D%s\033[K\033[%dD", buf+i, len-i);
+ }
+ break;
+ case KEY_DELETE: case KEY_CTRL_D:
+ if (i < len) {
+ memmove(buf+i, buf+i+1, len-i);
+ buf[--len] = 0;
+ if (i == len) fputs(" \033[D", out);
+ else fprintf(out, "%s\033[K\033[%dD", buf+i, len-i);
+ }
+ break;
+ case KEY_ARROW_LEFT: case KEY_CTRL_B:
+ if (i > 0) {
+ --i;
+ fputs("\033[D", out);
+ }
+ break;
+ case KEY_ARROW_RIGHT: case KEY_CTRL_F:
+ if (i < len) {
+ ++i;
+ fputs("\033[C", out);
+ }
+ break;
+ default:
+ if (' ' <= key && key <= '~') {
+ if (len + 1 >= (int)cap) {
+ cap += 100;
+ buf = realloc(buf, cap);
+ if (!buf) goto finished;
+ }
+ if (i < len)
+ memmove(buf+i+1, buf+i, len-i+1);
+ buf[i++] = (char)key;
+ buf[++len] = 0;
+ if (i == len)
+ fputc(key, out);
+ else
+ fprintf(out, "%c%s\033[%dD", (char)key, buf+i, len-i);
+ }
+ break;
+ }
+ }
+ finished:
+ // Reset cursor to block
+ fputs("\033[1G\033[1 q\033[2K", out);
+ return buf;
+}
+
+#endif
+// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-01 11:24:23 +0000