2 files changed, 47 insertions(+), 1 deletions(-)

M README.md
M f_asciihex.c

@@ 13,7 13,6 @@ specific object (text, images, fonts, etc).
 
 ## TODO
 
-* ASCIIHexDecode filter
 * CryptDecode filter
 * does DCTDecode filter need to deal with ColorTransform?
 * do we need predictor 5 ("optimum")?

@@ 4,6 4,53 @@
 
 /* 7.4.2 ASCIIHexDecode filter */
 
+static int
+hexc(int c)
+{
+	if(c >= 'A' && c <= 'F')
+		return c - 'A' + 10;
+	if(c >= '0' && c <= '9')
+		return c - '0';
+	if(c >= 'a' && c <= 'f')
+		return c - 'a' + 10;
+	return -1;
+}
+
+static int
+flreadall(void *aux, Buffer *bi, Buffer *bo)
+{
+	int i, insz, c, c2;
+	uchar *in, b;
+
+	USED(aux);
+
+	in = bufdata(bi, &insz);
+	for(i = 0; i < insz;){
+		if((c = hexc(in[i++])) < 0){
+			if(isws(in[i-1]))
+				continue;
+			if(in[i-1] == '>')
+				break;
+badchar:
+			werrstr("invalid char %02x", in[i-1]);
+			return -1;
+		}
+		c2 = 0;
+		if(i < insz && (c2 = hexc(in[i++])) < 0){
+			if(in[i-1] != '>')
+				c2 = 0;
+			else
+				goto badchar;
+		}
+		b = c<<4 | c2;
+		bufput(bo, &b, 1);
+	}
+	bi->off = bi->sz;
+
+	return 0;
+}
+
 Filter filterASCIIHex = {
 	.name = "ASCIIHexDecode",
+	.readall = flreadall,
 };