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RunLengthDecode

--- a/f_runlength.c

+++ b/f_runlength.c

@@ -2,11 +2,43 @@

 #include <libc.h>

 #include "pdf.h"

+/* 7.4.5 RunLengthDecode filter */

+

 static int

 flreadall(void *aux, Buffer *bi, Buffer *bo)

 {

+	int sz, i;

+	uchar *p;

+

 	USED(aux);

-	bufput(bo, bi->b, bi->sz);

+

+	p = bufdata(bi, &sz);

+	for(; sz > 0;){

+		i = *p++;

+		sz--;

+

+		if(i == 0x80) /* EOD */

+			break;

+		if(i > 0x80){

+			if(sz < 1){

+				werrstr("no byte to repeat");

+				return -1;

+			}

+			for(i = 257 - i; i > 0; i--)

+				bufput(bo, p, 1);

+		}else{

+			i++;

+			if(i > sz){

+				werrstr("short data");

+				return -1;

+			}

+			bufput(bo, p, i);

+			p += i;

+			sz -= i;

+		}

+	}

+	bi->off = bi->sz;

+

 	return 0;

 }