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Added q/Q standard (x-platform 8-byte ints) mode in struct module.

Browse source 
This completes the q/Q project.

longobject.c _PyLong_AsByteArray:  The original code had a gross bug:
the most-significant Python digit doesn't necessarily have SHIFT
significant bits, and you really need to count how many copies of the sign
bit it has else spurious overflow errors result.

test_struct.py:  This now does exhaustive std q/Q testing at, and on both
sides of, all relevant power-of-2 boundaries, both positive and negative.

NEWS:  Added brief dict news while I was at it.
This commit is contained in:
Tim Peters 2001-06-12 01:22:22 +00:00
parent ac4797a12e
commit 7a3bfc3a47
5 changed files with 337 additions and 77 deletions
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17
Doc/lib/libstruct.tex
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@ -72,7 +72,8 @@ Notes:
\item[(1)]
The \character{q} and \character{Q} conversion codes are available in
native mode only if the platform C compiler supports C \ctype{long long},
or, on Windows, \ctype{__int64}.
or, on Windows, \ctype{__int64}. They're always available in standard
modes.
\end{description}
@ -100,8 +101,8 @@ passed in to \function{pack()} is too long, the stored representation
is truncated. If the string is too short, padding is used to ensure
that exactly enough bytes are used to satisfy the count.
For the \character{I} and \character{L} format characters, the return
value is a Python long integer.
For the \character{I}, \character{L}, \character{q} and \character{Q}
format characters, the return value is a Python long integer.
For the \character{P} format character, the return value is a Python
integer or long integer, depending on the size needed to hold a
@ -139,10 +140,12 @@ Native size and alignment are determined using the C compiler's
order.
Standard size and alignment are as follows: no alignment is required
for any type (so you have to use pad bytes); \ctype{short} is 2 bytes;
\ctype{int} and \ctype{long} are 4 bytes. \ctype{float} and
\ctype{double} are 32-bit and 64-bit IEEE floating point numbers,
respectively.
for any type (so you have to use pad bytes);
\ctype{short} is 2 bytes;
\ctype{int} and \ctype{long} are 4 bytes;
\ctype{long long} (\ctype{__int64} on Windows) is 8 bytes;
\ctype{float} and \ctype{double} are 32-bit and 64-bit
IEEE floating point numbers, respectively.
Note the difference between \character{@} and \character{=}: both use
native byte order, but the size and alignment of the latter is