From 37da2899f40661e3e9631e497da8dc59b971cbd0 Mon Sep 17 00:00:00 2001 From: "Charles.Forsyth" Date: Fri, 22 Dec 2006 17:07:39 +0000 Subject: 20060303a --- libmp/port/mptole.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 libmp/port/mptole.c (limited to 'libmp/port/mptole.c') diff --git a/libmp/port/mptole.c b/libmp/port/mptole.c new file mode 100644 index 00000000..9421d5f6 --- /dev/null +++ b/libmp/port/mptole.c @@ -0,0 +1,54 @@ +#include "os.h" +#include +#include "dat.h" + +// convert an mpint into a little endian byte array (least significant byte first) + +// return number of bytes converted +// if p == nil, allocate and result array +int +mptole(mpint *b, uchar *p, uint n, uchar **pp) +{ + int i, j; + mpdigit x; + uchar *e, *s; + + if(p == nil){ + n = (b->top+1)*Dbytes; + p = malloc(n); + } + if(pp != nil) + *pp = p; + if(p == nil) + return -1; + memset(p, 0, n); + + // special case 0 + if(b->top == 0){ + if(n < 1) + return -1; + else + return 0; + } + + s = p; + e = s+n; + for(i = 0; i < b->top-1; i++){ + x = b->p[i]; + for(j = 0; j < Dbytes; j++){ + if(p >= e) + return -1; + *p++ = x; + x >>= 8; + } + } + x = b->p[i]; + while(x > 0){ + if(p >= e) + return -1; + *p++ = x; + x >>= 8; + } + + return p - s; +} -- cgit v1.2.3