1 files changed, 110 insertions, 0 deletions
diff --git a/libterminput_read_symbol__.c b/libterminput_read_symbol__.c
new file mode 100644
index 0000000..34f4b21
--- /dev/null
+++ b/libterminput_read_symbol__.c
@@ -0,0 +1,110 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+int
+libterminput_read_symbol__(int fd, struct input *input, struct libterminput_state *ctx)
+{
+	unsigned char c, tc;
+	ssize_t r;
+
+	/* Get next byte from input */
+	if (ctx->stored_head != ctx->stored_tail) {
+		c = ((unsigned char *)ctx->stored)[ctx->stored_tail++];
+		if (ctx->stored_tail == ctx->stored_head)
+			ctx->stored_tail = ctx->stored_head = 0;
+	} else {
+		r = read(fd, ctx->stored, sizeof(ctx->stored));
+		if (r <= 0)
+			return (int)r;
+		c = (unsigned char)ctx->stored[0];
+		if (r > 1) {
+			ctx->stored_tail = 1U;
+			ctx->stored_head = (size_t)r;
+		}
+	}
+
+	/* Check if symbol is complete or can be completed, and split out modifier */
+again:
+	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[(unsigned char)ctx->npartial] = '\0';
+			ctx->n = 0;
+			ctx->npartial = 0;
+			ctx->mods = 0;
+			ctx->stored[ctx->stored_head++] = (char)c;
+			strcpy(input->symbol, ctx->partial);
+			return 1;
+		} else {
+			/* Store byte, and if done, return */
+			ctx->partial[(unsigned char)ctx->npartial++] = (char)c;
+			if (ctx->npartial == ctx->n) {
+				ctx->partial[(unsigned char)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 && c != 0xFF) {
+		/* 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] = (char)c;
+			input->symbol[1] = '\0';
+			input->mods = ctx->mods;
+			ctx->mods = 0;
+			return 1;
+		}
+		ctx->partial[0] = (char)c;
+		ctx->npartial = 1;
+
+	} else if (c & 0x80) {
+		/* 8th bit set to signify META */
+		c ^= 0x80;
+		ctx->mods |= LIBTERMINPUT_META;
+		goto again;
+
+	} else {
+		/* Single-byte-character */
+		input->symbol[0] = (char)c;
+		input->symbol[1] = '\0';
+		input->mods = ctx->mods;
+		ctx->mods = 0;
+		return 1;
+	}
+
+	/* Incomplete symbol */
+	input->symbol[0] = '\0';
+	input->mods = -1;
+	return 1;
+}