1 files changed, 115 insertions, 0 deletions
diff --git a/atascii.c b/atascii.c
new file mode 100644
index 0000000..d1d1243
--- /dev/null
+++ b/atascii.c
@@ -0,0 +1,115 @@
+#include "atascii.h"
+
+const char *atascii_inverse_on  = "\x1b[7m";
+const char *atascii_inverse_off = "\x1b[27m";
+
+int atascii_context_init(atascii_ctx *ctx, int mode, int flags) {
+	memset(ctx, 0, sizeof(atascii_ctx));
+
+	switch(mode) {
+		case ATA_MODE_UTF8:
+			if(flags & ATA_FLAG_ICS)
+				ctx->table = ics2utf;
+			else
+				ctx->table = ata2utf;
+			break;
+		case ATA_MODE_MAGAZINE:
+			ctx->flags &= ~ATA_FLAG_UNDERLINE;
+			ctx->table = ata2mag;
+			break;
+		default:
+			return 0;
+	}
+
+	ctx->mode = mode;
+	ctx->flags = flags;
+
+	return 1;
+}
+
+char *atascii_a2utf(atascii_ctx *ctx, int src, char *dest) {
+	dest[0] = 0;
+
+	if(src == ATA_CHR_FINISH) {
+		if(ctx->inv)
+			strcpy(dest, atascii_inverse_off);
+		return dest;
+	}
+
+	if(src == 0x9b) {
+		strcpy(dest, "\n");
+		ctx->lines++;
+		return dest;
+	}
+
+	if(ctx->flags & ATA_FLAG_TEXTMODE) {
+		switch(src) {
+			case 0x7f: /* tab */
+				strcpy(dest, "\t");
+				return dest;
+			case 0xfd: /* bell */
+				strcpy(dest, "\a");
+				return dest;
+			case 0x7e: /* backspace */
+				strcpy(dest, "\b");
+				return dest;
+			default: break;
+		}
+	}
+
+	if(ctx->flags & ATA_FLAG_STRIP_INVERSE) src &= 0x7f;
+
+	if(!(ctx->flags & ATA_FLAG_UNDERLINE)) {
+		/* strings of inverse chars only get one "inverse on" ANSI
+			sequence, and one "inverse off" afterwards. */
+		if(src & 0x80) {
+			if(!ctx->inv) {
+				ctx->inv = 1;
+				if(ctx->mode == ATA_MODE_MAGAZINE) {
+					strcpy(dest, "{inv}");
+				} else {
+					strcpy(dest, atascii_inverse_on);
+				}
+			}
+		} else {
+			if(ctx->inv) {
+				ctx->inv = 0;
+				if(ctx->mode == ATA_MODE_MAGAZINE) {
+					strcpy(dest, "{norm}");
+				} else {
+					strcpy(dest, atascii_inverse_off);
+				}
+			}
+		}
+	}
+
+	if(ctx->mode == ATA_MODE_MAGAZINE) {
+		/* special cases: control codes with bit 7 set can't go
+			in the table since it's only got 128 entries. */
+		switch(src) {
+			case 0x9c:
+				strcat(dest, "{del-line}"); return dest;
+			case 0x9d:
+				strcat(dest, "{ins-line}"); return dest;
+			case 0x9e:
+				strcat(dest, "{clr-tab}"); return dest;
+			case 0x9f:
+				strcat(dest, "{set-tab}"); return dest;
+			case 0xfd:
+				strcat(dest, "{bell}"); return dest;
+			case 0xfe:
+				strcat(dest, "{del-char}"); return dest;
+			case 0xff:
+				strcat(dest, "{ins-char}"); return dest;
+			default: break;
+		}
+	}
+
+	strcat(dest, ctx->table[src & 0x7f]);
+
+	if((ctx->flags & ATA_FLAG_UNDERLINE) && (src & 0x80)) {
+		strcat(dest, "\b_");
+	}
+
+	return dest;
+}