From bedd2e7ccb1595c23e159eaa952ae1b0b5a3d2ad Mon Sep 17 00:00:00 2001 From: Simon Rettberg Date: Sat, 15 Mar 2014 01:49:50 +0100 Subject: Lean and mean initial commit Not much functionality yet --- fmt_asn1length.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 fmt_asn1length.c (limited to 'fmt_asn1length.c') diff --git a/fmt_asn1length.c b/fmt_asn1length.c new file mode 100644 index 0000000..3df929b --- /dev/null +++ b/fmt_asn1length.c @@ -0,0 +1,25 @@ +#include "asn1.h" + +/* write int in least amount of bytes, return number of bytes */ +/* as used in ASN.1 length */ +size_t fmt_asn1length(char* dest,size_t l) { + /* encoding is either l%128 or (0x80+number of bytes,bytes) */ + size_t needed=(sizeof l),i; + if (l<128) { + if (dest) *dest=l&0x7f; + return 1; + } + for (i=1; i>(i*8))) + break; + if (dest) { + int j=i; + *dest=0x80+i; ++dest; + while (j) { + --j; + *dest=((l>>(j*8))&0xff); + ++dest; + } + } + return i+1; +} -- cgit v1.2.3-55-g7522