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authorakr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2013-06-11 12:06:40 +0000
committerakr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2013-06-11 12:06:40 +0000
commitd5a3818f8e3d096a4e192b61008f886f940192df (patch)
tree4c8da8fb3d17f84b154c6af3f5565b2b54d07dcc
parentb7597efb48126e28dd0bbb12ef07a5e1066093fc (diff)
* bignum.c (rb_integer_pack_internal): Renamed from rb_integer_pack
and overflow_2comp argument added. (rb_integer_pack): Just call rb_integer_pack_internal. (rb_integer_pack_2comp): New function. * internal.h (rb_integer_pack_2comp): Declared. * sprintf.c (rb_str_format): Use rb_integer_pack and rb_integer_pack_2comp to format binary/octal/hexadecimal integers. (ruby_digitmap): Declared. (remove_sign_bits): Removed. (BITSPERDIG): Ditto. (EXTENDSIGN): Ditto. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41230 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
-rw-r--r--ChangeLog16
-rw-r--r--bignum.c183
-rw-r--r--ext/-test-/bignum/pack.c19
-rw-r--r--internal.h1
-rw-r--r--sprintf.c219
-rw-r--r--test/-ext-/bignum/test_pack.rb44
6 files changed, 326 insertions, 156 deletions
diff --git a/ChangeLog b/ChangeLog
index 4bbee66e61a..fdde53408d0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+Tue Jun 11 20:52:43 2013 Tanaka Akira <akr@fsij.org>
+
+ * bignum.c (rb_integer_pack_internal): Renamed from rb_integer_pack
+ and overflow_2comp argument added.
+ (rb_integer_pack): Just call rb_integer_pack_internal.
+ (rb_integer_pack_2comp): New function.
+
+ * internal.h (rb_integer_pack_2comp): Declared.
+
+ * sprintf.c (rb_str_format): Use rb_integer_pack and
+ rb_integer_pack_2comp to format binary/octal/hexadecimal integers.
+ (ruby_digitmap): Declared.
+ (remove_sign_bits): Removed.
+ (BITSPERDIG): Ditto.
+ (EXTENDSIGN): Ditto.
+
Tue Jun 11 16:15:03 2013 Nobuyoshi Nakada <nobu@ruby-lang.org>
* array.c (ary_shrink_capa): shrink the capacity so it fits just with
diff --git a/bignum.c b/bignum.c
index 61c854c18b4..20062e99ae8 100644
--- a/bignum.c
+++ b/bignum.c
@@ -842,37 +842,11 @@ integer_pack_take_lowbits(int n, BDIGIT_DBL *ddp, int *numbits_in_dd_p)
return ret;
}
-/*
- * Export an integer into a buffer.
- *
- * This function fills the buffer specified by _words_ and _numwords_ as
- * abs(val) in the format specified by _wordsize_, _nails_ and _flags_.
- *
- * [val] Fixnum, Bignum or another integer like object which has to_int method.
- * [words] buffer to export abs(val).
- * [numwords] the size of given buffer as number of words.
- * [wordsize] the size of word as number of bytes.
- * [nails] number of padding bits in a word.
- * Most significant nails bits of each word are filled by zero.
- * [flags] bitwise or of constants which name starts "INTEGER_PACK_".
- * It specifies word order and byte order.
- *
- * This function returns the signedness and overflow condition as follows:
- * -2 : negative overflow. val <= -2**(numwords*(wordsize*CHAR_BIT-nails))
- * -1 : negative without overflow. -2**(numwords*(wordsize*CHAR_BIT-nails)) < val < 0
- * 0 : zero. val == 0
- * 1 : positive without overflow. 0 < val < 2**(numwords*(wordsize*CHAR_BIT-nails))
- * 2 : positive overflow. 2**(numwords*(wordsize*CHAR_BIT-nails)) <= val
- *
- * The least significant words of abs(val) are filled in the buffer when overflow occur.
- */
-
-int
-rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t nails, int flags)
+static int
+rb_integer_pack_internal(VALUE val, void *words, size_t numwords, size_t wordsize, size_t nails, int flags, int overflow_2comp)
{
int sign;
- BDIGIT *dp;
- BDIGIT *de;
+ BDIGIT *ds, *dp, *de;
BDIGIT fixbuf[(sizeof(long) + SIZEOF_BDIGITS - 1) / SIZEOF_BDIGITS];
unsigned char *buf, *bufend;
@@ -902,12 +876,12 @@ rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t
}
}
#endif
- dp = fixbuf;
+ ds = dp = fixbuf;
de = fixbuf + numberof(fixbuf);
}
else {
sign = RBIGNUM_POSITIVE_P(val) ? 1 : -1;
- dp = BDIGITS(val);
+ ds = dp = BDIGITS(val);
de = dp + RBIGNUM_LEN(val);
}
while (dp < de && de[-1] == 0)
@@ -920,7 +894,15 @@ rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t
bufend = buf + numwords * wordsize;
if (buf == bufend) {
- sign *= 2; /* overflow if non-zero*/
+ /* overflow if non-zero*/
+ if (!overflow_2comp || 0 <= sign)
+ sign *= 2;
+ else {
+ if (de - dp == 1 && dp[0] == 1)
+ sign = -1; /* val == -1 == -2**(numwords*(wordsize*CHAR_BIT-nails)) */
+ else
+ sign = -2; /* val < -1 == -2**(numwords*(wordsize*CHAR_BIT-nails)) */
+ }
}
else if (dp == de) {
memset(buf, '\0', bufend - buf);
@@ -979,8 +961,28 @@ rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t
wordp += word_step;
}
- if (dp != de || dd)
- sign *= 2; /* overflow */
+ FILL_DD;
+ /* overflow tests */
+ if (dp != de || 1 < dd) {
+ /* 2**(numwords*(wordsize*CHAR_BIT-nails)+1) <= abs(val) */
+ sign *= 2;
+ }
+ else if (dd == 1) {
+ /* 2**(numwords*(wordsize*CHAR_BIT-nails)) <= abs(val) < 2**(numwords*(wordsize*CHAR_BIT-nails)+1) */
+ if (!overflow_2comp || 0 <= sign)
+ sign *= 2;
+ else { /* overflow_2comp && sign == -1 */
+ /* test lower bits are all zero. */
+ dp = ds;
+ while (dp < de && *dp == 0)
+ dp++;
+ if (de - dp == 1 && /* only one non-zero word. */
+ (*dp & (*dp-1)) == 0) /* *dp contains only one bit set. */
+ sign = -1; /* val == -2**(numwords*(wordsize*CHAR_BIT-nails)) */
+ else
+ sign = -2; /* val < -2**(numwords*(wordsize*CHAR_BIT-nails)) */
+ }
+ }
}
return sign;
@@ -988,6 +990,119 @@ rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t
#undef TAKE_LOWBITS
}
+/*
+ * Export an integer into a buffer.
+ *
+ * This function fills the buffer specified by _words_ and _numwords_ as
+ * abs(val) in the format specified by _wordsize_, _nails_ and _flags_.
+ *
+ * [val] Fixnum, Bignum or another integer like object which has to_int method.
+ * [words] buffer to export abs(val).
+ * [numwords] the size of given buffer as number of words.
+ * [wordsize] the size of word as number of bytes.
+ * [nails] number of padding bits in a word.
+ * Most significant nails bits of each word are filled by zero.
+ * [flags] bitwise or of constants which name starts "INTEGER_PACK_".
+ * It specifies word order and byte order.
+ *
+ * This function returns the signedness and overflow condition as follows:
+ * -2 : negative overflow. val <= -2**(numwords*(wordsize*CHAR_BIT-nails))
+ * -1 : negative without overflow. -2**(numwords*(wordsize*CHAR_BIT-nails)) < val < 0
+ * 0 : zero. val == 0
+ * 1 : positive without overflow. 0 < val < 2**(numwords*(wordsize*CHAR_BIT-nails))
+ * 2 : positive overflow. 2**(numwords*(wordsize*CHAR_BIT-nails)) <= val
+ *
+ * The least significant words of abs(val) are filled in the buffer when overflow occur.
+ */
+
+int
+rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t nails, int flags)
+{
+ return rb_integer_pack_internal(val, words, numwords, wordsize, nails, flags, 0);
+}
+
+/*
+ * Export an integer into a buffer in 2's comlement representation.
+ *
+ * This function is similar to rb_integer_pack_2comp but
+ * the number is filled as 2's comlement representation and
+ * return value is bit different (because overflow condition
+ * is differnt between absolute value and 2's comlement).
+ *
+ * This function returns the signedness and overflow condition as follows:
+ * -2 : negative overflow. val < -2**(numwords*(wordsize*CHAR_BIT-nails))
+ * -1 : negative without overflow. -2**(numwords*(wordsize*CHAR_BIT-nails)) <= val < 0
+ * 0 : zero. val == 0
+ * 1 : positive without overflow. 0 < val < 2**(numwords*(wordsize*CHAR_BIT-nails))
+ * 2 : positive overflow. 2**(numwords*(wordsize*CHAR_BIT-nails)) <= val
+ *
+ * rb_integer_pack_2comp returns -1 for val == -2**(numwords*(wordsize*CHAR_BIT-nails)) but
+ * rb_integer_pack returns -2.
+ *
+ */
+
+int
+rb_integer_pack_2comp(VALUE val, void *words, size_t numwords, size_t wordsize, size_t nails, int flags)
+{
+ int sign;
+
+ sign = rb_integer_pack_internal(val, words, numwords, wordsize, nails, flags, 1);
+
+ if (sign < 0 && numwords != 0) {
+ unsigned char *buf;
+
+ int word_num_partialbits;
+ size_t word_num_fullbytes;
+
+ ssize_t word_step;
+ size_t byte_start;
+ int byte_step;
+
+ size_t word_start, word_last;
+ unsigned char *wordp, *last_wordp;
+
+ unsigned int partialbits_mask;
+ int carry;
+
+ integer_pack_loop_setup(numwords, wordsize, nails, flags,
+ &word_num_fullbytes, &word_num_partialbits,
+ &word_start, &word_step, &word_last, &byte_start, &byte_step);
+
+ partialbits_mask = (1 << word_num_partialbits) - 1;
+
+ buf = words;
+ wordp = buf + word_start;
+ last_wordp = buf + word_last;
+
+ carry = 1;
+ while (1) {
+ size_t index_in_word = 0;
+ unsigned char *bytep = wordp + byte_start;
+ while (index_in_word < word_num_fullbytes) {
+ carry += (unsigned char)~*bytep;
+ *bytep = (unsigned char)carry;
+ carry >>= CHAR_BIT;
+ bytep += byte_step;
+ index_in_word++;
+ }
+ if (word_num_partialbits) {
+ carry += (*bytep & partialbits_mask) ^ partialbits_mask;
+ *bytep = carry & partialbits_mask;
+ carry >>= word_num_partialbits;
+ bytep += byte_step;
+ index_in_word++;
+ }
+
+ if (wordp == last_wordp)
+ break;
+
+ wordp += word_step;
+ }
+ }
+
+ return sign;
+}
+
static size_t
integer_unpack_num_bdigits_small(size_t numwords, size_t wordsize, size_t nails)
{
diff --git a/ext/-test-/bignum/pack.c b/ext/-test-/bignum/pack.c
index 62f8f62c2d3..6d646368d4a 100644
--- a/ext/-test-/bignum/pack.c
+++ b/ext/-test-/bignum/pack.c
@@ -19,6 +19,24 @@ rb_integer_pack_m(VALUE val, VALUE buf, VALUE wordsize_arg, VALUE nails, VALUE f
}
static VALUE
+rb_integer_pack_2comp_m(VALUE val, VALUE numwords_arg, VALUE wordsize_arg, VALUE nails, VALUE flags)
+{
+ int sign;
+ size_t numwords = NUM2SIZET(numwords_arg);
+ size_t wordsize = NUM2SIZET(wordsize_arg);
+ VALUE buf;
+
+ if (numwords != 0 && wordsize != 0 && LONG_MAX / wordsize < numwords)
+ rb_raise(rb_eArgError, "too big numwords * wordsize");
+ buf = rb_str_new(NULL, numwords * wordsize);
+ sign = rb_integer_pack_2comp(val,
+ RSTRING_PTR(buf), numwords,
+ wordsize, NUM2SIZET(nails), NUM2INT(flags));
+
+ return rb_assoc_new(INT2NUM(sign), buf);
+}
+
+static VALUE
rb_integer_unpack_m(VALUE klass, VALUE sign, VALUE buf, VALUE wordcount, VALUE wordsize, VALUE nails, VALUE flags)
{
StringValue(buf);
@@ -32,6 +50,7 @@ void
Init_pack(VALUE klass)
{
rb_define_method(rb_cInteger, "test_pack", rb_integer_pack_m, 4);
+ rb_define_method(rb_cInteger, "test_pack_2comp", rb_integer_pack_2comp_m, 4);
rb_define_singleton_method(rb_cInteger, "test_unpack", rb_integer_unpack_m, 6);
rb_define_const(rb_cInteger, "INTEGER_PACK_MSWORD_FIRST", INT2NUM(INTEGER_PACK_MSWORD_FIRST));
rb_define_const(rb_cInteger, "INTEGER_PACK_LSWORD_FIRST", INT2NUM(INTEGER_PACK_LSWORD_FIRST));
diff --git a/internal.h b/internal.h
index 0a79802bc67..bcc6c58a311 100644
--- a/internal.h
+++ b/internal.h
@@ -449,6 +449,7 @@ VALUE rb_thread_io_blocking_region(rb_blocking_function_t *func, void *data1, in
/* bignum.c */
int rb_integer_pack(VALUE val, void *words, size_t numwords, size_t wordsize, size_t nails, int flags);
VALUE rb_integer_unpack(int sign, const void *words, size_t numwords, size_t wordsize, size_t nails, int flags);
+int rb_integer_pack_2comp(VALUE val, void *words, size_t numwords, size_t wordsize, size_t nails, int flags);
/* io.c */
void rb_maygvl_fd_fix_cloexec(int fd);
diff --git a/sprintf.c b/sprintf.c
index c818eb5dfa6..2b0fb823f2c 100644
--- a/sprintf.c
+++ b/sprintf.c
@@ -23,35 +23,10 @@
#endif
#define BIT_DIGITS(N) (((N)*146)/485 + 1) /* log2(10) =~ 146/485 */
-#define BITSPERDIG (SIZEOF_BDIGITS*CHAR_BIT)
-#define EXTENDSIGN(n, l) (((~0 << (n)) >> (((n)*(l)) % BITSPERDIG)) & ~(~0 << (n)))
-static void fmt_setup(char*,size_t,int,int,int,int);
-
-static char*
-remove_sign_bits(char *str, int base)
-{
- char *t = str;
-
- if (base == 16) {
- while (*t == 'f') {
- t++;
- }
- }
- else if (base == 8) {
- *t |= EXTENDSIGN(3, strlen(t));
- while (*t == '7') {
- t++;
- }
- }
- else if (base == 2) {
- while (*t == '1') {
- t++;
- }
- }
+extern const char ruby_digitmap[];
- return t;
-}
+static void fmt_setup(char*,size_t,int,int,int,int);
static char
sign_bits(int base, const char *p)
@@ -758,6 +733,7 @@ rb_str_format(int argc, const VALUE *argv, VALUE fmt)
case 'u':
{
volatile VALUE val = GETARG();
+ int valsign;
char fbuf[32], nbuf[64], *s;
const char *prefix = 0;
int sign = 0, dots = 0;
@@ -835,96 +811,101 @@ rb_str_format(int argc, const VALUE *argv, VALUE fmt)
base = 10; break;
}
- if (!bignum) {
- if (base == 2) {
- val = rb_int2big(v);
- goto bin_retry;
- }
- if (sign) {
- char c = *p;
- if (c == 'i') c = 'd'; /* %d and %i are identical */
- if (v < 0) {
- v = -v;
- sc = '-';
- width--;
- }
- else if (flags & FPLUS) {
- sc = '+';
- width--;
- }
- else if (flags & FSPACE) {
- sc = ' ';
- width--;
- }
- snprintf(fbuf, sizeof(fbuf), "%%l%c", c);
- snprintf(nbuf, sizeof(nbuf), fbuf, v);
- s = nbuf;
- }
- else {
- s = nbuf;
- if (v < 0) {
- dots = 1;
- }
- snprintf(fbuf, sizeof(fbuf), "%%l%c", *p == 'X' ? 'x' : *p);
- snprintf(++s, sizeof(nbuf) - 1, fbuf, v);
- if (v < 0) {
- char d = 0;
-
- s = remove_sign_bits(s, base);
- switch (base) {
- case 16:
- d = 'f'; break;
- case 8:
- d = '7'; break;
- }
- if (d && *s != d) {
- *--s = d;
- }
- }
- }
+ if (base != 10) {
+ int numbits = ffs(base)-1;
+ size_t abs_nlz_bits;
+ size_t numdigits = rb_absint_numwords(val, numbits, &abs_nlz_bits);
+ long i;
+ if (INT_MAX-1 < numdigits) /* INT_MAX is used because rb_long2int is used later. */
+ rb_raise(rb_eArgError, "size too big");
+ if (sign) {
+ if (numdigits == 0)
+ numdigits = 1;
+ tmp = rb_str_new(NULL, numdigits);
+ valsign = rb_integer_pack(val, RSTRING_PTR(tmp), RSTRING_LEN(tmp),
+ 1, CHAR_BIT-numbits, INTEGER_PACK_BIG_ENDIAN);
+ for (i = 0; i < RSTRING_LEN(tmp); i++)
+ RSTRING_PTR(tmp)[i] = ruby_digitmap[((unsigned char *)RSTRING_PTR(tmp))[i]];
+ s = RSTRING_PTR(tmp);
+ if (valsign < 0) {
+ sc = '-';
+ width--;
+ }
+ else if (flags & FPLUS) {
+ sc = '+';
+ width--;
+ }
+ else if (flags & FSPACE) {
+ sc = ' ';
+ width--;
+ }
+ }
+ else {
+ /* Following conditional "numdigits++" guarantees the
+ * most significant digit as
+ * - '1'(bin), '7'(oct) or 'f'(hex) for negative numbers
+ * - '0' for zero
+ * - not '0' for positive numbers.
+ *
+ * It also guarantees the most significant two
+ * digits will not be '11'(bin), '77'(oct), 'ff'(hex)
+ * or '00'. */
+ if (numdigits == 0 ||
+ ((abs_nlz_bits != (size_t)(numbits-1) ||
+ !rb_absint_singlebit_p(val)) &&
+ (!bignum ? v < 0 : RBIGNUM_NEGATIVE_P(val))))
+ numdigits++;
+ tmp = rb_str_new(NULL, numdigits);
+ valsign = rb_integer_pack_2comp(val, RSTRING_PTR(tmp), RSTRING_LEN(tmp),
+ 1, CHAR_BIT-numbits, INTEGER_PACK_BIG_ENDIAN);
+ for (i = 0; i < RSTRING_LEN(tmp); i++)
+ RSTRING_PTR(tmp)[i] = ruby_digitmap[((unsigned char *)RSTRING_PTR(tmp))[i]];
+ s = RSTRING_PTR(tmp);
+ dots = valsign < 0;
+ }
+ len = rb_long2int(RSTRING_END(tmp) - s);
+ }
+ else if (!bignum) {
+ char c = *p;
+ if (c == 'i') c = 'd'; /* %d and %i are identical */
+ valsign = 1;
+ if (v < 0) {
+ v = -v;
+ sc = '-';
+ width--;
+ valsign = -1;
+ }
+ else if (flags & FPLUS) {
+ sc = '+';
+ width--;
+ }
+ else if (flags & FSPACE) {
+ sc = ' ';
+ width--;
+ }
+ snprintf(fbuf, sizeof(fbuf), "%%l%c", c);
+ snprintf(nbuf, sizeof(nbuf), fbuf, v);
+ s = nbuf;
len = (int)strlen(s);
}
else {
- if (sign) {
- tmp = rb_big2str(val, base);
- s = RSTRING_PTR(tmp);
- if (s[0] == '-') {
- s++;
- sc = '-';
- width--;
- }
- else if (flags & FPLUS) {
- sc = '+';
- width--;
- }
- else if (flags & FSPACE) {
- sc = ' ';
- width--;
- }
- }
- else {
- if (!RBIGNUM_SIGN(val)) {
- val = rb_big_clone(val);
- rb_big_2comp(val);
- }
- tmp = rb_big2str0(val, base, RBIGNUM_SIGN(val));
- s = RSTRING_PTR(tmp);
- if (*s == '-') {
- dots = 1;
- if (base == 10) {
- rb_warning("negative number for %%u specifier");
- }
- s = remove_sign_bits(++s, base);
- switch (base) {
- case 16:
- if (s[0] != 'f') *--s = 'f'; break;
- case 8:
- if (s[0] != '7') *--s = '7'; break;
- case 2:
- if (s[0] != '1') *--s = '1'; break;
- }
- }
- }
+ tmp = rb_big2str(val, base);
+ s = RSTRING_PTR(tmp);
+ valsign = 1;
+ if (s[0] == '-') {
+ s++;
+ sc = '-';
+ width--;
+ valsign = -1;
+ }
+ else if (flags & FPLUS) {
+ sc = '+';
+ width--;
+ }
+ else if (flags & FSPACE) {
+ sc = ' ';
+ width--;
+ }
len = rb_long2int(RSTRING_END(tmp) - s);
}
@@ -983,21 +964,15 @@ rb_str_format(int argc, const VALUE *argv, VALUE fmt)
}
CHECK(prec - len);
if (dots) PUSH("..", 2);
- if (!bignum && v < 0) {
+ if (!sign && valsign < 0) {
char c = sign_bits(base, p);
while (len < prec--) {
buf[blen++] = c;
}
}
else if ((flags & (FMINUS|FPREC)) != FMINUS) {
- char c;
-
- if (!sign && bignum && !RBIGNUM_SIGN(val))
- c = sign_bits(base, p);
- else
- c = '0';
while (len < prec--) {
- buf[blen++] = c;
+ buf[blen++] = '0';
}
}
PUSH(s, len);
diff --git a/test/-ext-/bignum/test_pack.rb b/test/-ext-/bignum/test_pack.rb
index 8b4f60d24d8..32b891c84c8 100644
--- a/test/-ext-/bignum/test_pack.rb
+++ b/test/-ext-/bignum/test_pack.rb
@@ -72,6 +72,50 @@ class TestBignum < Test::Unit::TestCase
assert_equal([-1, "\x80\x70\x60\x50\x40\x30\x20\x10", 8], (-0x8070605040302010).test_pack("xxxxxxxx", 1, 0, BIG_ENDIAN))
end
+ def test_pack2comp_zero
+ assert_equal([0, ""], 0.test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ end
+
+ def test_pack2comp_emptybuf
+ assert_equal([-2, ""], (-3).test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ assert_equal([-2, ""], (-2).test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ assert_equal([-1, ""], (-1).test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ assert_equal([ 0, ""], 0.test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ assert_equal([+2, ""], 1.test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ assert_equal([+2, ""], 2.test_pack_2comp(0, 1, 0, BIG_ENDIAN))
+ end
+
+ def test_pack2comp_nearly_zero
+ assert_equal([-1, "\xFE"], (-2).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([-1, "\xFF"], (-1).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([ 0, "\x00"], 0.test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([+1, "\x01"], 1.test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([+1, "\x02"], 2.test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ end
+
+ def test_pack2comp_overflow
+ assert_equal([-2, "\xF"], (-0x11).test_pack_2comp(1, 1, 4, BIG_ENDIAN))
+ assert_equal([-1, "\x0"], (-0x10).test_pack_2comp(1, 1, 4, BIG_ENDIAN))
+ assert_equal([-1, "\x1"], (-0x0F).test_pack_2comp(1, 1, 4, BIG_ENDIAN))
+ assert_equal([+1, "\xF"], (+0x0F).test_pack_2comp(1, 1, 4, BIG_ENDIAN))
+ assert_equal([+2, "\x0"], (+0x10).test_pack_2comp(1, 1, 4, BIG_ENDIAN))
+ assert_equal([+2, "\x1"], (+0x11).test_pack_2comp(1, 1, 4, BIG_ENDIAN))
+
+ assert_equal([-2, "\xFF"], (-0x101).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([-1, "\x00"], (-0x100).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([-1, "\x01"], (-0x0FF).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([+1, "\xFF"], (+0x0FF).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([+2, "\x00"], (+0x100).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+ assert_equal([+2, "\x01"], (+0x101).test_pack_2comp(1, 1, 0, BIG_ENDIAN))
+
+ assert_equal([-2, "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"], (-0x10000000000000001).test_pack_2comp(2, 4, 0, BIG_ENDIAN))
+ assert_equal([-1, "\x00\x00\x00\x00\x00\x00\x00\x00"], (-0x10000000000000000).test_pack_2comp(2, 4, 0, BIG_ENDIAN))
+ assert_equal([-1, "\x00\x00\x00\x00\x00\x00\x00\x01"], (-0x0FFFFFFFFFFFFFFFF).test_pack_2comp(2, 4, 0, BIG_ENDIAN))
+ assert_equal([+1, "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF"], (+0x0FFFFFFFFFFFFFFFF).test_pack_2comp(2, 4, 0, BIG_ENDIAN))
+ assert_equal([+2, "\x00\x00\x00\x00\x00\x00\x00\x00"], (+0x10000000000000000).test_pack_2comp(2, 4, 0, BIG_ENDIAN))
+ assert_equal([+2, "\x00\x00\x00\x00\x00\x00\x00\x01"], (+0x10000000000000001).test_pack_2comp(2, 4, 0, BIG_ENDIAN))
+ end
+
def test_unpack_zero
assert_equal(0, Integer.test_unpack(0, "", 0, 1, 0, BIG_ENDIAN))
end