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author | akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2010-03-04 14:20:49 +0000 |
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committer | akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2010-03-04 14:20:49 +0000 |
commit | ef7d0431a0c59839f555123ccd5ad06418209c0c (patch) | |
tree | 85741b20691fa10afe310aac8e5ab7dbb5e08fab /bignum.c | |
parent | 6bec06674c2a51af865a5d8d7c31d93799f98d59 (diff) | |
download | ruby-ef7d0431a0c59839f555123ccd5ad06418209c0c.tar.gz |
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git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@26818 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'bignum.c')
-rw-r--r-- | bignum.c | 14 |
1 files changed, 14 insertions, 0 deletions
@@ -308,6 +308,19 @@ rb_int2inum(SIGNED_VALUE n) # error unexpected SIZEOF_LONG : SIZEOF_BDIGITS ratio #endif +/* + * buf is an array of long integers. + * buf is ordered from least significant word to most significant word. + * buf[0] is the least significant word and + * buf[num_longs-1] is the most significant word. + * This means words in buf is little endian. + * However each word in buf is native endian. + * (buf[i]&1) is the least significant bit and + * (buf[i]&(1<<(SIZEOF_LONG*CHAR_BIT-1))) is the most significant bit + * for each 0 <= i < num_longs. + * So buf is little endian at whole on a little endian machine. + * But buf is mixed endian on a big endian machine. + */ void rb_big_pack(VALUE val, unsigned long *buf, long num_longs) { @@ -349,6 +362,7 @@ rb_big_pack(VALUE val, unsigned long *buf, long num_longs) } } +/* See rb_big_pack comment for endianness of buf. */ VALUE rb_big_unpack(unsigned long *buf, long num_longs) { |