First commit

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 345 insertions, 0 deletions

diff --git a/libterminput.c b/libterminput.c
new file mode 100644
index 0000000..a255373
--- /dev/null
+++ b/libterminput.c
@@ -0,0 +1,345 @@
+/* See LICENSE file for copyright and license details. */
+#include "libterminput.h"
+
+#include <alloca.h>
+#include <ctype.h>
+#include <limits.h>
+#include <string.h>
+#include <unistd.h>
+
+
+struct input {
+	enum libterminput_mod mods;
+	char symbol[7];
+};
+
+
+static int
+read_input(int fd, struct input *input, struct libterminput_state *ctx)
+{
+	unsigned char c, tc;
+	int r;
+
+	/* Get next byte from input */
+	if (ctx->have_stored) {
+		ctx->have_stored = 0;
+		c = (unsigned char)ctx->stored;
+	} else {
+		r = read(fd, &c, 1);
+		if (r <= 0)
+			return r;
+	}
+
+	if (ctx->n) {
+		/* Continuation of multibyte-character */
+		if ((c & 0xC0) != 0x80) {
+			/* Short multibyte-character: return short and store read byte from next input */
+			input->mods = ctx->mods;
+			ctx->partial[ctx->npartial] = '\0';
+			ctx->n = 0;
+			ctx->npartial = 0;
+			ctx->mods = 0;
+			ctx->have_stored = 1;
+			ctx->stored = (char)c;
+			strcpy(input->symbol, ctx->partial);
+			return 1;
+		} else {
+			/* Store byte, and if done, return */
+			ctx->partial[ctx->npartial++] = c;
+			if (ctx->npartial == ctx->n) {
+				ctx->partial[ctx->npartial] = '\0';
+				input->mods = ctx->mods;
+				ctx->npartial = 0;
+				ctx->mods = 0;
+				ctx->n = 0;
+				strcpy(input->symbol, ctx->partial);
+				return 1;
+			}
+		}
+	} else if (c == 033 && !*ctx->key) {
+		/* ESC at the beginning, save as a Meta/ESC */
+		ctx->meta += 1;
+	} else if (c == 0) {
+		/* CTRL on Space */
+		input->symbol[0] = ' ';
+		input->symbol[1] = '\0';
+		input->mods = ctx->mods | LIBTERMINPUT_CTRL;
+		ctx->mods = 0;
+		return 1;
+	} else if (c < (unsigned char)' ' && (char)c != '\t' && (char)c != '\b' && (char)c != '\n') {
+		/* CTRL on some some character key */
+		input->symbol[0] = (char)c + '@';
+		input->symbol[1] = '\0';
+		input->mods = ctx->mods | LIBTERMINPUT_CTRL;
+		ctx->mods = 0;
+		return 1;
+	} else if ((c & 0xC0) == 0xC0) {
+		/* Beginning of multibyte-character */
+		ctx->n = 0;
+		for (tc = c; tc & 0x80; tc <<= 1)
+			ctx->n++;
+		if (ctx->n > 6) {
+			/* If overlong, return first byte a single-byte-character */
+			input->symbol[0] = c;
+			input->symbol[1] = '\0';
+			input->mods = ctx->mods;
+			ctx->mods = 0;
+			return 1;
+		}
+		ctx->partial[0] = c;
+		ctx->npartial = 1;
+	} else {
+		/* Single-byte-character or stray multi-byte continuation byte */
+		input->symbol[0] = c;
+		input->symbol[1] = '\0';
+		input->mods = ctx->mods;
+		ctx->mods = 0;
+		return 1;
+	}
+
+	input->symbol[0] = '\0';
+	input->mods = -1;
+	return 1;
+}
+
+
+static void
+parse_sequence(union libterminput_input *input, struct libterminput_state *ctx)
+{
+	unsigned long long int *nums;
+	size_t keylen, n;
+	char *p;
+
+	/* Get number of numbers in the sequence, and allocate an array of at least 2 */
+	for (n = 2, p = ctx->key; *p; p++)
+		n += *p == ';';
+	nums = alloca(n * sizeof(*nums));
+	nums[0] = nums[1] = 0;
+
+	/* Read numbers and remove numbers and delimiters */
+	for (keylen = 0, n = 0, p = ctx->key; *p; p++) {
+		if (*p == ';') {
+			nums[++n] = 0; /* We made sure above to allocate one extra */
+		} else if (!isdigit(*p)) {
+			ctx->key[keylen++] = *p;
+		} else if (n < 3) {
+			if (nums[n] < (ULLONG_MAX - (*p & 15)) / 10)
+				nums[n] = nums[n] * 10 + (*p & 15);
+			else
+				nums[n] = ULLONG_MAX;
+		}
+	}
+	ctx->key[keylen] = '\0';
+
+	/* Get times and mods, and reset symbol, and more as keypress */
+	input->type = LIBTERMINPUT_KEYPRESS;
+	input->keypress.symbol[0] = '\0';
+	input->keypress.times = nums[0] + !nums[0];
+	input->keypress.mods = nums[1] > 1 ? nums[1] - 1 : 0;
+	input->keypress.mods |= ctx->meta > 1 ? LIBTERMINPUT_META : 0;
+
+	switch (ctx->key[0]) {
+	case '[':
+		switch (keylen) {
+		case 2:
+			switch (ctx->key[1]) {
+			case 'A': input->keypress.key = LIBTERMINPUT_UP;    break;
+			case 'B': input->keypress.key = LIBTERMINPUT_DOWN;  break;
+			case 'C': input->keypress.key = LIBTERMINPUT_RIGHT; break;
+			case 'D': input->keypress.key = LIBTERMINPUT_LEFT;  break;
+			case 'E': input->keypress.key = LIBTERMINPUT_BEGIN; break;
+			case 'G': input->keypress.key = LIBTERMINPUT_BEGIN; break;
+			case 'P': input->keypress.key = LIBTERMINPUT_PAUSE; break;
+			case 'Z':
+				input->keypress.key = LIBTERMINPUT_TAB;
+				input->keypress.mods |= LIBTERMINPUT_SHIFT;
+				break;
+			case '~':
+				input->keypress.times = 1;
+				switch (nums[0]) {
+				case  1: input->keypress.key = LIBTERMINPUT_HOME;  break;
+				case  2: input->keypress.key = LIBTERMINPUT_INS;   break;
+				case  3: input->keypress.key = LIBTERMINPUT_DEL;   break;
+				case  4: input->keypress.key = LIBTERMINPUT_END;   break;
+				case  5: input->keypress.key = LIBTERMINPUT_PRIOR; break;
+				case  6: input->keypress.key = LIBTERMINPUT_NEXT;  break;
+				case 15: input->keypress.key = LIBTERMINPUT_F5;    break;
+				case 17: input->keypress.key = LIBTERMINPUT_F6;    break;
+				case 18: input->keypress.key = LIBTERMINPUT_F7;    break;
+				case 19: input->keypress.key = LIBTERMINPUT_F8;    break;
+				case 20: input->keypress.key = LIBTERMINPUT_F9;    break;
+				case 21: input->keypress.key = LIBTERMINPUT_F10;   break;
+				case 23: input->keypress.key = LIBTERMINPUT_F11;   break;
+				case 24: input->keypress.key = LIBTERMINPUT_F12;   break;
+				case 25: input->keypress.key = LIBTERMINPUT_F1;    break;
+				case 26: input->keypress.key = LIBTERMINPUT_F2;    break;
+				case 28: input->keypress.key = LIBTERMINPUT_F3;    break;
+				case 29: input->keypress.key = LIBTERMINPUT_F4;    break;
+				case 31: input->keypress.key = LIBTERMINPUT_F5;    break;
+				case 32: input->keypress.key = LIBTERMINPUT_F6;    break;
+				case 33: input->keypress.key = LIBTERMINPUT_F7;    break;
+				case 34: input->keypress.key = LIBTERMINPUT_F8;    break;
+				default:
+					input->type = LIBTERMINPUT_NONE;
+					return;
+				}
+				if (25 <= nums[0] && nums[0] <= 34)
+					input->keypress.mods |= LIBTERMINPUT_SHIFT;
+				break;
+			default:
+				input->type = LIBTERMINPUT_NONE;
+				break;
+			}
+			break;
+		case 3:
+			switch (ctx->key[1] == '[' ? ctx->key[2] : 0) {
+			case 'A': input->keypress.key = LIBTERMINPUT_F1; break;
+			case 'B': input->keypress.key = LIBTERMINPUT_F2; break;
+			case 'C': input->keypress.key = LIBTERMINPUT_F3; break;
+			case 'D': input->keypress.key = LIBTERMINPUT_F4; break;
+			case 'E': input->keypress.key = LIBTERMINPUT_F5; break;
+			default:
+				input->type = LIBTERMINPUT_NONE;
+				break;
+			}
+			break;
+		default:
+			input->type = LIBTERMINPUT_NONE;
+			break;
+		}
+		break;
+
+	case 'O':
+		switch (!ctx->key[2] ? ctx->key[1] : 0) {
+		case 'H': input->keypress.key = LIBTERMINPUT_HOME;         break;
+		case 'F': input->keypress.key = LIBTERMINPUT_END;          break;
+		case 'P': input->keypress.key = LIBTERMINPUT_F1;           break;
+		case 'Q': input->keypress.key = LIBTERMINPUT_F2;           break;
+		case 'R': input->keypress.key = LIBTERMINPUT_F3;           break;
+		case 'S': input->keypress.key = LIBTERMINPUT_F4;           break;
+		case 'p': input->keypress.key = LIBTERMINPUT_KEYPAD_0;     break;
+		case 'q': input->keypress.key = LIBTERMINPUT_KEYPAD_1;     break;
+		case 'r': input->keypress.key = LIBTERMINPUT_KEYPAD_2;     break;
+		case 's': input->keypress.key = LIBTERMINPUT_KEYPAD_3;     break;
+		case 't': input->keypress.key = LIBTERMINPUT_KEYPAD_4;     break;
+		case 'u': input->keypress.key = LIBTERMINPUT_KEYPAD_5;     break;
+		case 'v': input->keypress.key = LIBTERMINPUT_KEYPAD_6;     break;
+		case 'w': input->keypress.key = LIBTERMINPUT_KEYPAD_7;     break;
+		case 'x': input->keypress.key = LIBTERMINPUT_KEYPAD_8;     break;
+		case 'y': input->keypress.key = LIBTERMINPUT_KEYPAD_9;     break;
+		case 'm': input->keypress.key = LIBTERMINPUT_KEYPAD_MINUS; break;
+		case 'l': input->keypress.key = LIBTERMINPUT_KEYPAD_COMMA; break;
+		case 'b': input->keypress.key = LIBTERMINPUT_KEYPAD_POINT; break;
+		case 'M': input->keypress.key = LIBTERMINPUT_KEYPAD_ENTER; break;
+		default:
+			input->type = LIBTERMINPUT_NONE;
+			break;
+		}
+		break;
+
+	default:
+		/* This shouldn't happen */
+		input->type = LIBTERMINPUT_NONE;
+		break;
+	}		
+}
+
+
+int
+libterminput_read(int fd, union libterminput_input *input, struct libterminput_state *ctx)
+{
+	struct input ret;
+	size_t n, m;
+	char *p;
+	int r;
+
+	if (!ctx->inited) {
+		ctx->inited = 1;
+		memset(input, 0, sizeof(*input));
+	} else if (input->type == LIBTERMINPUT_KEYPRESS && input->keypress.times > 1) {
+		input->keypress.times -= 1;
+		return 1;
+	}
+
+	r = read_input(fd, &ret, ctx);
+	if (r <= 0)
+		return r;
+
+again:
+	if (!*ret.symbol) {
+		/* Incomplete input */
+		if (ctx->meta < 3) {
+			/* Up to two Meta/ESC, wait until a third or something else is read */
+			input->type = LIBTERMINPUT_NONE;
+			return 1;
+		}
+		/* Three ESC's */
+		input->type = LIBTERMINPUT_KEYPRESS;
+		input->keypress.key = LIBTERMINPUT_ESC;
+		input->keypress.times = 3;
+		input->keypress.mods = ret.mods;
+		input->keypress.symbol[0] = '\0';
+		ctx->meta -= 3;
+	} else if (*ctx->key) {
+		/* Special keys */
+		if (ret.mods) {
+			/* Special key was aborted, restart */
+			*ctx->key = '\0';
+			goto again;
+		}
+		/* Add new input to sequence */
+		n = strlen(ctx->key);
+		m = strlen(ret.symbol);
+		if (n + m >= sizeof(ctx->key)) {
+			/* Abort if too long */
+			input->type = LIBTERMINPUT_NONE;
+			return 1;
+		}
+		p = stpcpy(&ctx->key[n], ret.symbol);
+		/* Check if sequence is complete */
+		if (!isalpha(p[-1]) && p[-1] != '~') {
+			input->type = LIBTERMINPUT_NONE;
+			return 1;
+		}
+		/* Parse the complete sequence */
+		parse_sequence(input, ctx);
+		/* Reset */
+		ctx->meta = 0;
+		ctx->key[0] = '\0';
+	} else if (ctx->meta && (!strcmp(ret.symbol, "[") || !strcmp(ret.symbol, "O"))) {
+		/* ESC [ or ESC 0 is used as the beginning of most special keys */
+		strcpy(ctx->key, ret.symbol);
+		input->type == LIBTERMINPUT_NONE;
+	} else {
+		/* Character input and single-byte special keys */
+		input->type = LIBTERMINPUT_KEYPRESS;
+		input->keypress.mods = ret.mods;
+		input->keypress.times = 1;
+		if (ctx->meta) {
+			/* Transfer meta modifier from state to input */
+			input->keypress.mods |= LIBTERMINPUT_META;
+			ctx->meta = 0;
+		}
+		switch (ret.symbol[1] ? 0 : ret.symbol[0]) {
+		case 127:
+		case '\b':
+			input->keypress.key = LIBTERMINPUT_ERASE;
+			input->keypress.symbol[0] = '\0';
+			break;
+		case '\t':
+			input->keypress.key = LIBTERMINPUT_TAB;
+			input->keypress.symbol[0] = '\0';
+			break;
+		case '\n':
+			input->keypress.key = LIBTERMINPUT_ENTER;
+			input->keypress.symbol[0] = '\0';
+			break;
+		default:
+			input->keypress.key = LIBTERMINPUT_SYMBOL;
+			strcpy(input->keypress.symbol, ret.symbol);
+			break;
+		}
+	}
+
+	return 1;
+}