mirror of
https://github.com/python/cpython.git
synced 2024-11-30 05:15:14 +08:00
d5fadf75e4
Add definitions of INT_MAX and LONG_MAX to pyport.h. Remove includes of limits.h and conditional definitions of INT_MAX and LONG_MAX elsewhere. This closes SourceForge patch #101659 and bug #115323.
1272 lines
25 KiB
C
1272 lines
25 KiB
C
|
|
/* struct module -- pack values into and (out of) strings */
|
|
|
|
/* New version supporting byte order, alignment and size options,
|
|
character strings, and unsigned numbers */
|
|
|
|
static char struct__doc__[] = "\
|
|
Functions to convert between Python values and C structs.\n\
|
|
Python strings are used to hold the data representing the C struct\n\
|
|
and also as format strings to describe the layout of data in the C struct.\n\
|
|
\n\
|
|
The optional first format char indicates byte ordering and alignment:\n\
|
|
@: native w/native alignment(default)\n\
|
|
=: native w/standard alignment\n\
|
|
<: little-endian, std. alignment\n\
|
|
>: big-endian, std. alignment\n\
|
|
!: network, std (same as >)\n\
|
|
\n\
|
|
The remaining chars indicate types of args and must match exactly;\n\
|
|
these can be preceded by a decimal repeat count:\n\
|
|
x: pad byte (no data); c:char; b:signed byte; B:unsigned byte;\n\
|
|
h:short; H:unsigned short; i:int; I:unsigned int;\n\
|
|
l:long; L:unsigned long; f:float; d:double.\n\
|
|
Special cases (preceding decimal count indicates length):\n\
|
|
s:string (array of char); p: pascal string (w. count byte).\n\
|
|
Special case (only available in native format):\n\
|
|
P:an integer type that is wide enough to hold a pointer.\n\
|
|
Whitespace between formats is ignored.\n\
|
|
\n\
|
|
The variable struct.error is an exception raised on errors.";
|
|
|
|
#include "Python.h"
|
|
|
|
#include <ctype.h>
|
|
|
|
|
|
/* Exception */
|
|
|
|
static PyObject *StructError;
|
|
|
|
|
|
/* Define various structs to figure out the alignments of types */
|
|
|
|
#ifdef __MWERKS__
|
|
/*
|
|
** XXXX We have a problem here. There are no unique alignment rules
|
|
** on the PowerPC mac.
|
|
*/
|
|
#ifdef __powerc
|
|
#pragma options align=mac68k
|
|
#endif
|
|
#endif /* __MWERKS__ */
|
|
|
|
typedef struct { char c; short x; } s_short;
|
|
typedef struct { char c; int x; } s_int;
|
|
typedef struct { char c; long x; } s_long;
|
|
typedef struct { char c; float x; } s_float;
|
|
typedef struct { char c; double x; } s_double;
|
|
typedef struct { char c; void *x; } s_void_p;
|
|
|
|
#define SHORT_ALIGN (sizeof(s_short) - sizeof(short))
|
|
#define INT_ALIGN (sizeof(s_int) - sizeof(int))
|
|
#define LONG_ALIGN (sizeof(s_long) - sizeof(long))
|
|
#define FLOAT_ALIGN (sizeof(s_float) - sizeof(float))
|
|
#define DOUBLE_ALIGN (sizeof(s_double) - sizeof(double))
|
|
#define VOID_P_ALIGN (sizeof(s_void_p) - sizeof(void *))
|
|
|
|
#define STRINGIFY(x) #x
|
|
|
|
#ifdef __powerc
|
|
#pragma options align=reset
|
|
#endif
|
|
|
|
/* Helper routine to get a Python integer and raise the appropriate error
|
|
if it isn't one */
|
|
|
|
static int
|
|
get_long(PyObject *v, long *p)
|
|
{
|
|
long x = PyInt_AsLong(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
if (PyErr_ExceptionMatches(PyExc_TypeError))
|
|
PyErr_SetString(StructError,
|
|
"required argument is not an integer");
|
|
return -1;
|
|
}
|
|
*p = x;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Same, but handling unsigned long */
|
|
|
|
static int
|
|
get_ulong(PyObject *v, unsigned long *p)
|
|
{
|
|
if (PyLong_Check(v)) {
|
|
unsigned long x = PyLong_AsUnsignedLong(v);
|
|
if (x == (unsigned long)(-1) && PyErr_Occurred())
|
|
return -1;
|
|
*p = x;
|
|
return 0;
|
|
}
|
|
else {
|
|
return get_long(v, (long *)p);
|
|
}
|
|
}
|
|
|
|
|
|
/* Floating point helpers */
|
|
|
|
/* These use ANSI/IEEE Standard 754-1985 (Standard for Binary Floating
|
|
Point Arithmetic). See the following URL:
|
|
http://www.psc.edu/general/software/packages/ieee/ieee.html */
|
|
|
|
/* XXX Inf/NaN are not handled quite right (but underflow is!) */
|
|
|
|
static int
|
|
pack_float(double x, /* The number to pack */
|
|
char *p, /* Where to pack the high order byte */
|
|
int incr) /* 1 for big-endian; -1 for little-endian */
|
|
{
|
|
int s;
|
|
int e;
|
|
double f;
|
|
long fbits;
|
|
|
|
if (x < 0) {
|
|
s = 1;
|
|
x = -x;
|
|
}
|
|
else
|
|
s = 0;
|
|
|
|
f = frexp(x, &e);
|
|
|
|
/* Normalize f to be in the range [1.0, 2.0) */
|
|
if (0.5 <= f && f < 1.0) {
|
|
f *= 2.0;
|
|
e--;
|
|
}
|
|
else if (f == 0.0) {
|
|
e = 0;
|
|
}
|
|
else {
|
|
PyErr_SetString(PyExc_SystemError,
|
|
"frexp() result out of range");
|
|
return -1;
|
|
}
|
|
|
|
if (e >= 128) {
|
|
/* XXX 128 itself is reserved for Inf/NaN */
|
|
PyErr_SetString(PyExc_OverflowError,
|
|
"float too large to pack with f format");
|
|
return -1;
|
|
}
|
|
else if (e < -126) {
|
|
/* Gradual underflow */
|
|
f = ldexp(f, 126 + e);
|
|
e = 0;
|
|
}
|
|
else if (!(e == 0 && f == 0.0)) {
|
|
e += 127;
|
|
f -= 1.0; /* Get rid of leading 1 */
|
|
}
|
|
|
|
f *= 8388608.0; /* 2**23 */
|
|
fbits = (long) floor(f + 0.5); /* Round */
|
|
|
|
/* First byte */
|
|
*p = (s<<7) | (e>>1);
|
|
p += incr;
|
|
|
|
/* Second byte */
|
|
*p = (char) (((e&1)<<7) | (fbits>>16));
|
|
p += incr;
|
|
|
|
/* Third byte */
|
|
*p = (fbits>>8) & 0xFF;
|
|
p += incr;
|
|
|
|
/* Fourth byte */
|
|
*p = fbits&0xFF;
|
|
|
|
/* Done */
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
pack_double(double x, /* The number to pack */
|
|
char *p, /* Where to pack the high order byte */
|
|
int incr) /* 1 for big-endian; -1 for little-endian */
|
|
{
|
|
int s;
|
|
int e;
|
|
double f;
|
|
long fhi, flo;
|
|
|
|
if (x < 0) {
|
|
s = 1;
|
|
x = -x;
|
|
}
|
|
else
|
|
s = 0;
|
|
|
|
f = frexp(x, &e);
|
|
|
|
/* Normalize f to be in the range [1.0, 2.0) */
|
|
if (0.5 <= f && f < 1.0) {
|
|
f *= 2.0;
|
|
e--;
|
|
}
|
|
else if (f == 0.0) {
|
|
e = 0;
|
|
}
|
|
else {
|
|
PyErr_SetString(PyExc_SystemError,
|
|
"frexp() result out of range");
|
|
return -1;
|
|
}
|
|
|
|
if (e >= 1024) {
|
|
/* XXX 1024 itself is reserved for Inf/NaN */
|
|
PyErr_SetString(PyExc_OverflowError,
|
|
"float too large to pack with d format");
|
|
return -1;
|
|
}
|
|
else if (e < -1022) {
|
|
/* Gradual underflow */
|
|
f = ldexp(f, 1022 + e);
|
|
e = 0;
|
|
}
|
|
else if (!(e == 0 && f == 0.0)) {
|
|
e += 1023;
|
|
f -= 1.0; /* Get rid of leading 1 */
|
|
}
|
|
|
|
/* fhi receives the high 28 bits; flo the low 24 bits (== 52 bits) */
|
|
f *= 268435456.0; /* 2**28 */
|
|
fhi = (long) floor(f); /* Truncate */
|
|
f -= (double)fhi;
|
|
f *= 16777216.0; /* 2**24 */
|
|
flo = (long) floor(f + 0.5); /* Round */
|
|
|
|
/* First byte */
|
|
*p = (s<<7) | (e>>4);
|
|
p += incr;
|
|
|
|
/* Second byte */
|
|
*p = (char) (((e&0xF)<<4) | (fhi>>24));
|
|
p += incr;
|
|
|
|
/* Third byte */
|
|
*p = (fhi>>16) & 0xFF;
|
|
p += incr;
|
|
|
|
/* Fourth byte */
|
|
*p = (fhi>>8) & 0xFF;
|
|
p += incr;
|
|
|
|
/* Fifth byte */
|
|
*p = fhi & 0xFF;
|
|
p += incr;
|
|
|
|
/* Sixth byte */
|
|
*p = (flo>>16) & 0xFF;
|
|
p += incr;
|
|
|
|
/* Seventh byte */
|
|
*p = (flo>>8) & 0xFF;
|
|
p += incr;
|
|
|
|
/* Eighth byte */
|
|
*p = flo & 0xFF;
|
|
p += incr;
|
|
|
|
/* Done */
|
|
return 0;
|
|
}
|
|
|
|
static PyObject *
|
|
unpack_float(const char *p, /* Where the high order byte is */
|
|
int incr) /* 1 for big-endian; -1 for little-endian */
|
|
{
|
|
int s;
|
|
int e;
|
|
long f;
|
|
double x;
|
|
|
|
/* First byte */
|
|
s = (*p>>7) & 1;
|
|
e = (*p & 0x7F) << 1;
|
|
p += incr;
|
|
|
|
/* Second byte */
|
|
e |= (*p>>7) & 1;
|
|
f = (*p & 0x7F) << 16;
|
|
p += incr;
|
|
|
|
/* Third byte */
|
|
f |= (*p & 0xFF) << 8;
|
|
p += incr;
|
|
|
|
/* Fourth byte */
|
|
f |= *p & 0xFF;
|
|
|
|
x = (double)f / 8388608.0;
|
|
|
|
/* XXX This sadly ignores Inf/NaN issues */
|
|
if (e == 0)
|
|
e = -126;
|
|
else {
|
|
x += 1.0;
|
|
e -= 127;
|
|
}
|
|
x = ldexp(x, e);
|
|
|
|
if (s)
|
|
x = -x;
|
|
|
|
return PyFloat_FromDouble(x);
|
|
}
|
|
|
|
static PyObject *
|
|
unpack_double(const char *p, /* Where the high order byte is */
|
|
int incr) /* 1 for big-endian; -1 for little-endian */
|
|
{
|
|
int s;
|
|
int e;
|
|
long fhi, flo;
|
|
double x;
|
|
|
|
/* First byte */
|
|
s = (*p>>7) & 1;
|
|
e = (*p & 0x7F) << 4;
|
|
p += incr;
|
|
|
|
/* Second byte */
|
|
e |= (*p>>4) & 0xF;
|
|
fhi = (*p & 0xF) << 24;
|
|
p += incr;
|
|
|
|
/* Third byte */
|
|
fhi |= (*p & 0xFF) << 16;
|
|
p += incr;
|
|
|
|
/* Fourth byte */
|
|
fhi |= (*p & 0xFF) << 8;
|
|
p += incr;
|
|
|
|
/* Fifth byte */
|
|
fhi |= *p & 0xFF;
|
|
p += incr;
|
|
|
|
/* Sixth byte */
|
|
flo = (*p & 0xFF) << 16;
|
|
p += incr;
|
|
|
|
/* Seventh byte */
|
|
flo |= (*p & 0xFF) << 8;
|
|
p += incr;
|
|
|
|
/* Eighth byte */
|
|
flo |= *p & 0xFF;
|
|
p += incr;
|
|
|
|
x = (double)fhi + (double)flo / 16777216.0; /* 2**24 */
|
|
x /= 268435456.0; /* 2**28 */
|
|
|
|
/* XXX This sadly ignores Inf/NaN */
|
|
if (e == 0)
|
|
e = -1022;
|
|
else {
|
|
x += 1.0;
|
|
e -= 1023;
|
|
}
|
|
x = ldexp(x, e);
|
|
|
|
if (s)
|
|
x = -x;
|
|
|
|
return PyFloat_FromDouble(x);
|
|
}
|
|
|
|
|
|
/* The translation function for each format character is table driven */
|
|
|
|
typedef struct _formatdef {
|
|
char format;
|
|
int size;
|
|
int alignment;
|
|
PyObject* (*unpack)(const char *,
|
|
const struct _formatdef *);
|
|
int (*pack)(char *, PyObject *,
|
|
const struct _formatdef *);
|
|
} formatdef;
|
|
|
|
static PyObject *
|
|
nu_char(const char *p, const formatdef *f)
|
|
{
|
|
return PyString_FromStringAndSize(p, 1);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_byte(const char *p, const formatdef *f)
|
|
{
|
|
return PyInt_FromLong((long) *(signed char *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_ubyte(const char *p, const formatdef *f)
|
|
{
|
|
return PyInt_FromLong((long) *(unsigned char *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_short(const char *p, const formatdef *f)
|
|
{
|
|
return PyInt_FromLong((long) *(short *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_ushort(const char *p, const formatdef *f)
|
|
{
|
|
return PyInt_FromLong((long) *(unsigned short *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_int(const char *p, const formatdef *f)
|
|
{
|
|
return PyInt_FromLong((long) *(int *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_uint(const char *p, const formatdef *f)
|
|
{
|
|
unsigned int x = *(unsigned int *)p;
|
|
return PyLong_FromUnsignedLong((unsigned long)x);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_long(const char *p, const formatdef *f)
|
|
{
|
|
return PyInt_FromLong(*(long *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_ulong(const char *p, const formatdef *f)
|
|
{
|
|
return PyLong_FromUnsignedLong(*(unsigned long *)p);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_float(const char *p, const formatdef *f)
|
|
{
|
|
float x;
|
|
memcpy((char *)&x, p, sizeof(float));
|
|
return PyFloat_FromDouble((double)x);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_double(const char *p, const formatdef *f)
|
|
{
|
|
double x;
|
|
memcpy((char *)&x, p, sizeof(double));
|
|
return PyFloat_FromDouble(x);
|
|
}
|
|
|
|
static PyObject *
|
|
nu_void_p(const char *p, const formatdef *f)
|
|
{
|
|
return PyLong_FromVoidPtr(*(void **)p);
|
|
}
|
|
|
|
static int
|
|
np_byte(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
if (x < -128 || x > 127){
|
|
PyErr_SetString(StructError,
|
|
"byte format requires -128<=number<=127");
|
|
return -1;
|
|
}
|
|
*p = (char)x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_ubyte(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
if (x < 0 || x > 255){
|
|
PyErr_SetString(StructError,
|
|
"ubyte format requires 0<=number<=255");
|
|
return -1;
|
|
}
|
|
*p = (char)x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_char(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
if (!PyString_Check(v) || PyString_Size(v) != 1) {
|
|
PyErr_SetString(StructError,
|
|
"char format require string of length 1");
|
|
return -1;
|
|
}
|
|
*p = *PyString_AsString(v);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_short(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
if (x < SHRT_MIN || x > SHRT_MAX){
|
|
PyErr_SetString(StructError,
|
|
"short format requires " STRINGIFY(SHRT_MIN)
|
|
"<=number<=" STRINGIFY(SHRT_MAX));
|
|
return -1;
|
|
}
|
|
* (short *)p = (short)x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_ushort(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
if (x < 0 || x > USHRT_MAX){
|
|
PyErr_SetString(StructError,
|
|
"short format requires 0<=number<=" STRINGIFY(USHRT_MAX));
|
|
return -1;
|
|
}
|
|
* (unsigned short *)p = (unsigned short)x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_int(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
* (int *)p = x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_uint(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
unsigned long x;
|
|
if (get_ulong(v, &x) < 0)
|
|
return -1;
|
|
* (unsigned int *)p = x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_long(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
* (long *)p = x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_ulong(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
unsigned long x;
|
|
if (get_ulong(v, &x) < 0)
|
|
return -1;
|
|
* (unsigned long *)p = x;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_float(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
float x = (float)PyFloat_AsDouble(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
PyErr_SetString(StructError,
|
|
"required argument is not a float");
|
|
return -1;
|
|
}
|
|
memcpy(p, (char *)&x, sizeof(float));
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_double(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
double x = PyFloat_AsDouble(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
PyErr_SetString(StructError,
|
|
"required argument is not a float");
|
|
return -1;
|
|
}
|
|
memcpy(p, (char *)&x, sizeof(double));
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
np_void_p(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
void *x = PyLong_AsVoidPtr(v);
|
|
if (x == NULL && PyErr_Occurred()) {
|
|
/* ### hrm. PyLong_AsVoidPtr raises SystemError */
|
|
if (PyErr_ExceptionMatches(PyExc_TypeError))
|
|
PyErr_SetString(StructError,
|
|
"required argument is not an integer");
|
|
return -1;
|
|
}
|
|
*(void **)p = x;
|
|
return 0;
|
|
}
|
|
|
|
static formatdef native_table[] = {
|
|
{'x', sizeof(char), 0, NULL},
|
|
{'b', sizeof(char), 0, nu_byte, np_byte},
|
|
{'B', sizeof(char), 0, nu_ubyte, np_ubyte},
|
|
{'c', sizeof(char), 0, nu_char, np_char},
|
|
{'s', sizeof(char), 0, NULL},
|
|
{'p', sizeof(char), 0, NULL},
|
|
{'h', sizeof(short), SHORT_ALIGN, nu_short, np_short},
|
|
{'H', sizeof(short), SHORT_ALIGN, nu_ushort, np_ushort},
|
|
{'i', sizeof(int), INT_ALIGN, nu_int, np_int},
|
|
{'I', sizeof(int), INT_ALIGN, nu_uint, np_uint},
|
|
{'l', sizeof(long), LONG_ALIGN, nu_long, np_long},
|
|
{'L', sizeof(long), LONG_ALIGN, nu_ulong, np_ulong},
|
|
{'f', sizeof(float), FLOAT_ALIGN, nu_float, np_float},
|
|
{'d', sizeof(double), DOUBLE_ALIGN, nu_double, np_double},
|
|
{'P', sizeof(void *), VOID_P_ALIGN, nu_void_p, np_void_p},
|
|
{0}
|
|
};
|
|
|
|
static PyObject *
|
|
bu_int(const char *p, const formatdef *f)
|
|
{
|
|
long x = 0;
|
|
int i = f->size;
|
|
do {
|
|
x = (x<<8) | (*p++ & 0xFF);
|
|
} while (--i > 0);
|
|
i = 8*(sizeof(long) - f->size);
|
|
if (i) {
|
|
x <<= i;
|
|
x >>= i;
|
|
}
|
|
return PyInt_FromLong(x);
|
|
}
|
|
|
|
static PyObject *
|
|
bu_uint(const char *p, const formatdef *f)
|
|
{
|
|
unsigned long x = 0;
|
|
int i = f->size;
|
|
do {
|
|
x = (x<<8) | (*p++ & 0xFF);
|
|
} while (--i > 0);
|
|
if (f->size >= 4)
|
|
return PyLong_FromUnsignedLong(x);
|
|
else
|
|
return PyInt_FromLong((long)x);
|
|
}
|
|
|
|
static PyObject *
|
|
bu_float(const char *p, const formatdef *f)
|
|
{
|
|
return unpack_float(p, 1);
|
|
}
|
|
|
|
static PyObject *
|
|
bu_double(const char *p, const formatdef *f)
|
|
{
|
|
return unpack_double(p, 1);
|
|
}
|
|
|
|
static int
|
|
bp_int(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
int i;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
i = f->size;
|
|
do {
|
|
p[--i] = (char)x;
|
|
x >>= 8;
|
|
} while (i > 0);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bp_uint(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
unsigned long x;
|
|
int i;
|
|
if (get_ulong(v, &x) < 0)
|
|
return -1;
|
|
i = f->size;
|
|
do {
|
|
p[--i] = (char)x;
|
|
x >>= 8;
|
|
} while (i > 0);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
bp_float(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
double x = PyFloat_AsDouble(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
PyErr_SetString(StructError,
|
|
"required argument is not a float");
|
|
return -1;
|
|
}
|
|
return pack_float(x, p, 1);
|
|
}
|
|
|
|
static int
|
|
bp_double(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
double x = PyFloat_AsDouble(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
PyErr_SetString(StructError,
|
|
"required argument is not a float");
|
|
return -1;
|
|
}
|
|
return pack_double(x, p, 1);
|
|
}
|
|
|
|
static formatdef bigendian_table[] = {
|
|
{'x', 1, 0, NULL},
|
|
{'b', 1, 0, bu_int, bp_int},
|
|
{'B', 1, 0, bu_uint, bp_int},
|
|
{'c', 1, 0, nu_char, np_char},
|
|
{'s', 1, 0, NULL},
|
|
{'p', 1, 0, NULL},
|
|
{'h', 2, 0, bu_int, bp_int},
|
|
{'H', 2, 0, bu_uint, bp_uint},
|
|
{'i', 4, 0, bu_int, bp_int},
|
|
{'I', 4, 0, bu_uint, bp_uint},
|
|
{'l', 4, 0, bu_int, bp_int},
|
|
{'L', 4, 0, bu_uint, bp_uint},
|
|
{'f', 4, 0, bu_float, bp_float},
|
|
{'d', 8, 0, bu_double, bp_double},
|
|
{0}
|
|
};
|
|
|
|
static PyObject *
|
|
lu_int(const char *p, const formatdef *f)
|
|
{
|
|
long x = 0;
|
|
int i = f->size;
|
|
do {
|
|
x = (x<<8) | (p[--i] & 0xFF);
|
|
} while (i > 0);
|
|
i = 8*(sizeof(long) - f->size);
|
|
if (i) {
|
|
x <<= i;
|
|
x >>= i;
|
|
}
|
|
return PyInt_FromLong(x);
|
|
}
|
|
|
|
static PyObject *
|
|
lu_uint(const char *p, const formatdef *f)
|
|
{
|
|
unsigned long x = 0;
|
|
int i = f->size;
|
|
do {
|
|
x = (x<<8) | (p[--i] & 0xFF);
|
|
} while (i > 0);
|
|
if (f->size >= 4)
|
|
return PyLong_FromUnsignedLong(x);
|
|
else
|
|
return PyInt_FromLong((long)x);
|
|
}
|
|
|
|
static PyObject *
|
|
lu_float(const char *p, const formatdef *f)
|
|
{
|
|
return unpack_float(p+3, -1);
|
|
}
|
|
|
|
static PyObject *
|
|
lu_double(const char *p, const formatdef *f)
|
|
{
|
|
return unpack_double(p+7, -1);
|
|
}
|
|
|
|
static int
|
|
lp_int(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
long x;
|
|
int i;
|
|
if (get_long(v, &x) < 0)
|
|
return -1;
|
|
i = f->size;
|
|
do {
|
|
*p++ = (char)x;
|
|
x >>= 8;
|
|
} while (--i > 0);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
lp_uint(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
unsigned long x;
|
|
int i;
|
|
if (get_ulong(v, &x) < 0)
|
|
return -1;
|
|
i = f->size;
|
|
do {
|
|
*p++ = (char)x;
|
|
x >>= 8;
|
|
} while (--i > 0);
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
lp_float(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
double x = PyFloat_AsDouble(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
PyErr_SetString(StructError,
|
|
"required argument is not a float");
|
|
return -1;
|
|
}
|
|
return pack_float(x, p+3, -1);
|
|
}
|
|
|
|
static int
|
|
lp_double(char *p, PyObject *v, const formatdef *f)
|
|
{
|
|
double x = PyFloat_AsDouble(v);
|
|
if (x == -1 && PyErr_Occurred()) {
|
|
PyErr_SetString(StructError,
|
|
"required argument is not a float");
|
|
return -1;
|
|
}
|
|
return pack_double(x, p+7, -1);
|
|
}
|
|
|
|
static formatdef lilendian_table[] = {
|
|
{'x', 1, 0, NULL},
|
|
{'b', 1, 0, lu_int, lp_int},
|
|
{'B', 1, 0, lu_uint, lp_int},
|
|
{'c', 1, 0, nu_char, np_char},
|
|
{'s', 1, 0, NULL},
|
|
{'p', 1, 0, NULL},
|
|
{'h', 2, 0, lu_int, lp_int},
|
|
{'H', 2, 0, lu_uint, lp_uint},
|
|
{'i', 4, 0, lu_int, lp_int},
|
|
{'I', 4, 0, lu_uint, lp_uint},
|
|
{'l', 4, 0, lu_int, lp_int},
|
|
{'L', 4, 0, lu_uint, lp_uint},
|
|
{'f', 4, 0, lu_float, lp_float},
|
|
{'d', 8, 0, lu_double, lp_double},
|
|
{0}
|
|
};
|
|
|
|
|
|
static const formatdef *
|
|
whichtable(char **pfmt)
|
|
{
|
|
const char *fmt = (*pfmt)++; /* May be backed out of later */
|
|
switch (*fmt) {
|
|
case '<':
|
|
return lilendian_table;
|
|
case '>':
|
|
case '!': /* Network byte order is big-endian */
|
|
return bigendian_table;
|
|
case '=': { /* Host byte order -- different from native in aligment! */
|
|
int n = 1;
|
|
char *p = (char *) &n;
|
|
if (*p == 1)
|
|
return lilendian_table;
|
|
else
|
|
return bigendian_table;
|
|
}
|
|
default:
|
|
--*pfmt; /* Back out of pointer increment */
|
|
/* Fall through */
|
|
case '@':
|
|
return native_table;
|
|
}
|
|
}
|
|
|
|
|
|
/* Get the table entry for a format code */
|
|
|
|
static const formatdef *
|
|
getentry(int c, const formatdef *f)
|
|
{
|
|
for (; f->format != '\0'; f++) {
|
|
if (f->format == c) {
|
|
return f;
|
|
}
|
|
}
|
|
PyErr_SetString(StructError, "bad char in struct format");
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/* Align a size according to a format code */
|
|
|
|
static int
|
|
align(int size, int c, const formatdef *e)
|
|
{
|
|
if (e->format == c) {
|
|
if (e->alignment) {
|
|
size = ((size + e->alignment - 1)
|
|
/ e->alignment)
|
|
* e->alignment;
|
|
}
|
|
}
|
|
return size;
|
|
}
|
|
|
|
|
|
/* calculate the size of a format string */
|
|
|
|
static int
|
|
calcsize(const char *fmt, const formatdef *f)
|
|
{
|
|
const formatdef *e;
|
|
const char *s;
|
|
char c;
|
|
int size, num, itemsize, x;
|
|
|
|
s = fmt;
|
|
size = 0;
|
|
while ((c = *s++) != '\0') {
|
|
if (isspace((int)c))
|
|
continue;
|
|
if ('0' <= c && c <= '9') {
|
|
num = c - '0';
|
|
while ('0' <= (c = *s++) && c <= '9') {
|
|
x = num*10 + (c - '0');
|
|
if (x/10 != num) {
|
|
PyErr_SetString(
|
|
StructError,
|
|
"overflow in item count");
|
|
return -1;
|
|
}
|
|
num = x;
|
|
}
|
|
if (c == '\0')
|
|
break;
|
|
}
|
|
else
|
|
num = 1;
|
|
|
|
e = getentry(c, f);
|
|
if (e == NULL)
|
|
return -1;
|
|
itemsize = e->size;
|
|
size = align(size, c, e);
|
|
x = num * itemsize;
|
|
size += x;
|
|
if (x/itemsize != num || size < 0) {
|
|
PyErr_SetString(StructError,
|
|
"total struct size too long");
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return size;
|
|
}
|
|
|
|
|
|
static char calcsize__doc__[] = "\
|
|
calcsize(fmt) -> int\n\
|
|
Return size of C struct described by format string fmt.\n\
|
|
See struct.__doc__ for more on format strings.";
|
|
|
|
static PyObject *
|
|
struct_calcsize(PyObject *self, PyObject *args)
|
|
{
|
|
char *fmt;
|
|
const formatdef *f;
|
|
int size;
|
|
|
|
if (!PyArg_ParseTuple(args, "s:calcsize", &fmt))
|
|
return NULL;
|
|
f = whichtable(&fmt);
|
|
size = calcsize(fmt, f);
|
|
if (size < 0)
|
|
return NULL;
|
|
return PyInt_FromLong((long)size);
|
|
}
|
|
|
|
|
|
static char pack__doc__[] = "\
|
|
pack(fmt, v1, v2, ...) -> string\n\
|
|
Return string containing values v1, v2, ... packed according to fmt.\n\
|
|
See struct.__doc__ for more on format strings.";
|
|
|
|
static PyObject *
|
|
struct_pack(PyObject *self, PyObject *args)
|
|
{
|
|
const formatdef *f, *e;
|
|
PyObject *format, *result, *v;
|
|
char *fmt;
|
|
int size, num;
|
|
int i, n;
|
|
char *s, *res, *restart, *nres;
|
|
char c;
|
|
|
|
if (args == NULL || !PyTuple_Check(args) ||
|
|
(n = PyTuple_Size(args)) < 1)
|
|
{
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"struct.pack requires at least one argument");
|
|
return NULL;
|
|
}
|
|
format = PyTuple_GetItem(args, 0);
|
|
if (!PyArg_Parse(format, "s", &fmt))
|
|
return NULL;
|
|
f = whichtable(&fmt);
|
|
size = calcsize(fmt, f);
|
|
if (size < 0)
|
|
return NULL;
|
|
result = PyString_FromStringAndSize((char *)NULL, size);
|
|
if (result == NULL)
|
|
return NULL;
|
|
|
|
s = fmt;
|
|
i = 1;
|
|
res = restart = PyString_AsString(result);
|
|
|
|
while ((c = *s++) != '\0') {
|
|
if (isspace((int)c))
|
|
continue;
|
|
if ('0' <= c && c <= '9') {
|
|
num = c - '0';
|
|
while ('0' <= (c = *s++) && c <= '9')
|
|
num = num*10 + (c - '0');
|
|
if (c == '\0')
|
|
break;
|
|
}
|
|
else
|
|
num = 1;
|
|
|
|
e = getentry(c, f);
|
|
if (e == NULL)
|
|
goto fail;
|
|
nres = restart + align((int)(res-restart), c, e);
|
|
/* Fill padd bytes with zeros */
|
|
while (res < nres)
|
|
*res++ = '\0';
|
|
if (num == 0 && c != 's')
|
|
continue;
|
|
do {
|
|
if (c == 'x') {
|
|
/* doesn't consume arguments */
|
|
memset(res, '\0', num);
|
|
res += num;
|
|
break;
|
|
}
|
|
if (i >= n) {
|
|
PyErr_SetString(StructError,
|
|
"insufficient arguments to pack");
|
|
goto fail;
|
|
}
|
|
v = PyTuple_GetItem(args, i++);
|
|
if (v == NULL)
|
|
goto fail;
|
|
if (c == 's') {
|
|
/* num is string size, not repeat count */
|
|
int n;
|
|
if (!PyString_Check(v)) {
|
|
PyErr_SetString(StructError,
|
|
"argument for 's' must be a string");
|
|
goto fail;
|
|
}
|
|
n = PyString_Size(v);
|
|
if (n > num)
|
|
n = num;
|
|
if (n > 0)
|
|
memcpy(res, PyString_AsString(v), n);
|
|
if (n < num)
|
|
memset(res+n, '\0', num-n);
|
|
res += num;
|
|
break;
|
|
}
|
|
else if (c == 'p') {
|
|
/* num is string size + 1,
|
|
to fit in the count byte */
|
|
int n;
|
|
num--; /* now num is max string size */
|
|
if (!PyString_Check(v)) {
|
|
PyErr_SetString(StructError,
|
|
"argument for 'p' must be a string");
|
|
goto fail;
|
|
}
|
|
n = PyString_Size(v);
|
|
if (n > num)
|
|
n = num;
|
|
if (n > 0)
|
|
memcpy(res+1, PyString_AsString(v), n);
|
|
if (n < num)
|
|
/* no real need, just to be nice */
|
|
memset(res+1+n, '\0', num-n);
|
|
*res++ = n; /* store the length byte */
|
|
res += num;
|
|
break;
|
|
}
|
|
else {
|
|
if (e->pack(res, v, e) < 0)
|
|
goto fail;
|
|
res += e->size;
|
|
}
|
|
} while (--num > 0);
|
|
}
|
|
|
|
if (i < n) {
|
|
PyErr_SetString(StructError,
|
|
"too many arguments for pack format");
|
|
goto fail;
|
|
}
|
|
|
|
return result;
|
|
|
|
fail:
|
|
Py_DECREF(result);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
static char unpack__doc__[] = "\
|
|
unpack(fmt, string) -> (v1, v2, ...)\n\
|
|
Unpack the string, containing packed C structure data, according\n\
|
|
to fmt. Requires len(string)==calcsize(fmt).\n\
|
|
See struct.__doc__ for more on format strings.";
|
|
|
|
static PyObject *
|
|
struct_unpack(PyObject *self, PyObject *args)
|
|
{
|
|
const formatdef *f, *e;
|
|
char *str, *start, *fmt, *s;
|
|
char c;
|
|
int len, size, num;
|
|
PyObject *res, *v;
|
|
|
|
if (!PyArg_ParseTuple(args, "ss#:unpack", &fmt, &start, &len))
|
|
return NULL;
|
|
f = whichtable(&fmt);
|
|
size = calcsize(fmt, f);
|
|
if (size < 0)
|
|
return NULL;
|
|
if (size != len) {
|
|
PyErr_SetString(StructError,
|
|
"unpack str size does not match format");
|
|
return NULL;
|
|
}
|
|
res = PyList_New(0);
|
|
if (res == NULL)
|
|
return NULL;
|
|
str = start;
|
|
s = fmt;
|
|
while ((c = *s++) != '\0') {
|
|
if (isspace((int)c))
|
|
continue;
|
|
if ('0' <= c && c <= '9') {
|
|
num = c - '0';
|
|
while ('0' <= (c = *s++) && c <= '9')
|
|
num = num*10 + (c - '0');
|
|
if (c == '\0')
|
|
break;
|
|
}
|
|
else
|
|
num = 1;
|
|
|
|
e = getentry(c, f);
|
|
if (e == NULL)
|
|
goto fail;
|
|
str = start + align((int)(str-start), c, e);
|
|
if (num == 0 && c != 's')
|
|
continue;
|
|
|
|
do {
|
|
if (c == 'x') {
|
|
str += num;
|
|
break;
|
|
}
|
|
if (c == 's') {
|
|
/* num is string size, not repeat count */
|
|
v = PyString_FromStringAndSize(str, num);
|
|
if (v == NULL)
|
|
goto fail;
|
|
str += num;
|
|
num = 0;
|
|
}
|
|
else if (c == 'p') {
|
|
/* num is string buffer size,
|
|
not repeat count */
|
|
int n = *(unsigned char*)str;
|
|
/* first byte (unsigned) is string size */
|
|
if (n >= num)
|
|
n = num-1;
|
|
v = PyString_FromStringAndSize(str+1, n);
|
|
if (v == NULL)
|
|
goto fail;
|
|
str += num;
|
|
num = 0;
|
|
}
|
|
else {
|
|
v = e->unpack(str, e);
|
|
if (v == NULL)
|
|
goto fail;
|
|
str += e->size;
|
|
}
|
|
if (v == NULL || PyList_Append(res, v) < 0)
|
|
goto fail;
|
|
Py_DECREF(v);
|
|
} while (--num > 0);
|
|
}
|
|
|
|
v = PyList_AsTuple(res);
|
|
Py_DECREF(res);
|
|
return v;
|
|
|
|
fail:
|
|
Py_DECREF(res);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/* List of functions */
|
|
|
|
static PyMethodDef struct_methods[] = {
|
|
{"calcsize", struct_calcsize, METH_VARARGS, calcsize__doc__},
|
|
{"pack", struct_pack, METH_VARARGS, pack__doc__},
|
|
{"unpack", struct_unpack, METH_VARARGS, unpack__doc__},
|
|
{NULL, NULL} /* sentinel */
|
|
};
|
|
|
|
|
|
/* Module initialization */
|
|
|
|
DL_EXPORT(void)
|
|
initstruct(void)
|
|
{
|
|
PyObject *m, *d;
|
|
|
|
/* Create the module and add the functions */
|
|
m = Py_InitModule4("struct", struct_methods, struct__doc__,
|
|
(PyObject*)NULL, PYTHON_API_VERSION);
|
|
|
|
/* Add some symbolic constants to the module */
|
|
d = PyModule_GetDict(m);
|
|
StructError = PyErr_NewException("struct.error", NULL, NULL);
|
|
if (StructError == NULL)
|
|
return;
|
|
PyDict_SetItemString(d, "error", StructError);
|
|
}
|