| /* struct module -- pack values into and (out of) bytes objects */ |
| |
| /* New version supporting byte order, alignment and size options, |
| character strings, and unsigned numbers */ |
| |
| #define PY_SSIZE_T_CLEAN |
| |
| #include "Python.h" |
| #include "structmember.h" |
| #include <ctype.h> |
| |
| static PyTypeObject PyStructType; |
| |
| /* The translation function for each format character is table driven */ |
| typedef struct _formatdef { |
| char format; |
| Py_ssize_t size; |
| Py_ssize_t alignment; |
| PyObject* (*unpack)(const char *, |
| const struct _formatdef *); |
| int (*pack)(char *, PyObject *, |
| const struct _formatdef *); |
| } formatdef; |
| |
| typedef struct _formatcode { |
| const struct _formatdef *fmtdef; |
| Py_ssize_t offset; |
| Py_ssize_t size; |
| Py_ssize_t repeat; |
| } formatcode; |
| |
| /* Struct object interface */ |
| |
| typedef struct { |
| PyObject_HEAD |
| Py_ssize_t s_size; |
| Py_ssize_t s_len; |
| formatcode *s_codes; |
| PyObject *s_format; |
| PyObject *weakreflist; /* List of weak references */ |
| } PyStructObject; |
| |
| |
| #define PyStruct_Check(op) PyObject_TypeCheck(op, &PyStructType) |
| #define PyStruct_CheckExact(op) (Py_TYPE(op) == &PyStructType) |
| |
| |
| /* Exception */ |
| |
| static PyObject *StructError; |
| |
| |
| /* Define various structs to figure out the alignments of types */ |
| |
| |
| typedef struct { char c; short x; } st_short; |
| typedef struct { char c; int x; } st_int; |
| typedef struct { char c; long x; } st_long; |
| typedef struct { char c; float x; } st_float; |
| typedef struct { char c; double x; } st_double; |
| typedef struct { char c; void *x; } st_void_p; |
| typedef struct { char c; size_t x; } st_size_t; |
| |
| #define SHORT_ALIGN (sizeof(st_short) - sizeof(short)) |
| #define INT_ALIGN (sizeof(st_int) - sizeof(int)) |
| #define LONG_ALIGN (sizeof(st_long) - sizeof(long)) |
| #define FLOAT_ALIGN (sizeof(st_float) - sizeof(float)) |
| #define DOUBLE_ALIGN (sizeof(st_double) - sizeof(double)) |
| #define VOID_P_ALIGN (sizeof(st_void_p) - sizeof(void *)) |
| #define SIZE_T_ALIGN (sizeof(st_size_t) - sizeof(size_t)) |
| |
| /* We can't support q and Q in native mode unless the compiler does; |
| in std mode, they're 8 bytes on all platforms. */ |
| #ifdef HAVE_LONG_LONG |
| typedef struct { char c; PY_LONG_LONG x; } s_long_long; |
| #define LONG_LONG_ALIGN (sizeof(s_long_long) - sizeof(PY_LONG_LONG)) |
| #endif |
| |
| #ifdef HAVE_C99_BOOL |
| #define BOOL_TYPE _Bool |
| typedef struct { char c; _Bool x; } s_bool; |
| #define BOOL_ALIGN (sizeof(s_bool) - sizeof(BOOL_TYPE)) |
| #else |
| #define BOOL_TYPE char |
| #define BOOL_ALIGN 0 |
| #endif |
| |
| #ifdef __powerc |
| #pragma options align=reset |
| #endif |
| |
| /* Helper for integer format codes: converts an arbitrary Python object to a |
| PyLongObject if possible, otherwise fails. Caller should decref. */ |
| |
| static PyObject * |
| get_pylong(PyObject *v) |
| { |
| assert(v != NULL); |
| if (!PyLong_Check(v)) { |
| /* Not an integer; try to use __index__ to convert. */ |
| if (PyIndex_Check(v)) { |
| v = PyNumber_Index(v); |
| if (v == NULL) |
| return NULL; |
| } |
| else { |
| PyErr_SetString(StructError, |
| "required argument is not an integer"); |
| return NULL; |
| } |
| } |
| else |
| Py_INCREF(v); |
| |
| assert(PyLong_Check(v)); |
| return v; |
| } |
| |
| /* Helper routine to get a C long and raise the appropriate error if it isn't |
| one */ |
| |
| static int |
| get_long(PyObject *v, long *p) |
| { |
| long x; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsLong(v); |
| Py_DECREF(v); |
| if (x == (long)-1 && PyErr_Occurred()) { |
| if (PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "argument out of range"); |
| return -1; |
| } |
| *p = x; |
| return 0; |
| } |
| |
| |
| /* Same, but handling unsigned long */ |
| |
| static int |
| get_ulong(PyObject *v, unsigned long *p) |
| { |
| unsigned long x; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsUnsignedLong(v); |
| Py_DECREF(v); |
| if (x == (unsigned long)-1 && PyErr_Occurred()) { |
| if (PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "argument out of range"); |
| return -1; |
| } |
| *p = x; |
| return 0; |
| } |
| |
| #ifdef HAVE_LONG_LONG |
| |
| /* Same, but handling native long long. */ |
| |
| static int |
| get_longlong(PyObject *v, PY_LONG_LONG *p) |
| { |
| PY_LONG_LONG x; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsLongLong(v); |
| Py_DECREF(v); |
| if (x == (PY_LONG_LONG)-1 && PyErr_Occurred()) { |
| if (PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "argument out of range"); |
| return -1; |
| } |
| *p = x; |
| return 0; |
| } |
| |
| /* Same, but handling native unsigned long long. */ |
| |
| static int |
| get_ulonglong(PyObject *v, unsigned PY_LONG_LONG *p) |
| { |
| unsigned PY_LONG_LONG x; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsUnsignedLongLong(v); |
| Py_DECREF(v); |
| if (x == (unsigned PY_LONG_LONG)-1 && PyErr_Occurred()) { |
| if (PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "argument out of range"); |
| return -1; |
| } |
| *p = x; |
| return 0; |
| } |
| |
| #endif |
| |
| /* Same, but handling Py_ssize_t */ |
| |
| static int |
| get_ssize_t(PyObject *v, Py_ssize_t *p) |
| { |
| Py_ssize_t x; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsSsize_t(v); |
| Py_DECREF(v); |
| if (x == (Py_ssize_t)-1 && PyErr_Occurred()) { |
| if (PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "argument out of range"); |
| return -1; |
| } |
| *p = x; |
| return 0; |
| } |
| |
| /* Same, but handling size_t */ |
| |
| static int |
| get_size_t(PyObject *v, size_t *p) |
| { |
| size_t x; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsSize_t(v); |
| Py_DECREF(v); |
| if (x == (size_t)-1 && PyErr_Occurred()) { |
| if (PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "argument out of range"); |
| return -1; |
| } |
| *p = x; |
| return 0; |
| } |
| |
| |
| #define RANGE_ERROR(x, f, flag, mask) return _range_error(f, flag) |
| |
| |
| /* Floating point helpers */ |
| |
| static PyObject * |
| unpack_float(const char *p, /* start of 4-byte string */ |
| int le) /* true for little-endian, false for big-endian */ |
| { |
| double x; |
| |
| x = _PyFloat_Unpack4((unsigned char *)p, le); |
| if (x == -1.0 && PyErr_Occurred()) |
| return NULL; |
| return PyFloat_FromDouble(x); |
| } |
| |
| static PyObject * |
| unpack_double(const char *p, /* start of 8-byte string */ |
| int le) /* true for little-endian, false for big-endian */ |
| { |
| double x; |
| |
| x = _PyFloat_Unpack8((unsigned char *)p, le); |
| if (x == -1.0 && PyErr_Occurred()) |
| return NULL; |
| return PyFloat_FromDouble(x); |
| } |
| |
| /* Helper to format the range error exceptions */ |
| static int |
| _range_error(const formatdef *f, int is_unsigned) |
| { |
| /* ulargest is the largest unsigned value with f->size bytes. |
| * Note that the simpler: |
| * ((size_t)1 << (f->size * 8)) - 1 |
| * doesn't work when f->size == sizeof(size_t) because C doesn't |
| * define what happens when a left shift count is >= the number of |
| * bits in the integer being shifted; e.g., on some boxes it doesn't |
| * shift at all when they're equal. |
| */ |
| const size_t ulargest = (size_t)-1 >> ((SIZEOF_SIZE_T - f->size)*8); |
| assert(f->size >= 1 && f->size <= SIZEOF_SIZE_T); |
| if (is_unsigned) |
| PyErr_Format(StructError, |
| "'%c' format requires 0 <= number <= %zu", |
| f->format, |
| ulargest); |
| else { |
| const Py_ssize_t largest = (Py_ssize_t)(ulargest >> 1); |
| PyErr_Format(StructError, |
| "'%c' format requires %zd <= number <= %zd", |
| f->format, |
| ~ largest, |
| largest); |
| } |
| |
| return -1; |
| } |
| |
| |
| |
| /* A large number of small routines follow, with names of the form |
| |
| [bln][up]_TYPE |
| |
| [bln] distiguishes among big-endian, little-endian and native. |
| [pu] distiguishes between pack (to struct) and unpack (from struct). |
| TYPE is one of char, byte, ubyte, etc. |
| */ |
| |
| /* Native mode routines. ****************************************************/ |
| /* NOTE: |
| In all n[up]_<type> routines handling types larger than 1 byte, there is |
| *no* guarantee that the p pointer is properly aligned for each type, |
| therefore memcpy is called. An intermediate variable is used to |
| compensate for big-endian architectures. |
| Normally both the intermediate variable and the memcpy call will be |
| skipped by C optimisation in little-endian architectures (gcc >= 2.91 |
| does this). */ |
| |
| static PyObject * |
| nu_char(const char *p, const formatdef *f) |
| { |
| return PyBytes_FromStringAndSize(p, 1); |
| } |
| |
| static PyObject * |
| nu_byte(const char *p, const formatdef *f) |
| { |
| return PyLong_FromLong((long) *(signed char *)p); |
| } |
| |
| static PyObject * |
| nu_ubyte(const char *p, const formatdef *f) |
| { |
| return PyLong_FromLong((long) *(unsigned char *)p); |
| } |
| |
| static PyObject * |
| nu_short(const char *p, const formatdef *f) |
| { |
| short x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromLong((long)x); |
| } |
| |
| static PyObject * |
| nu_ushort(const char *p, const formatdef *f) |
| { |
| unsigned short x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromLong((long)x); |
| } |
| |
| static PyObject * |
| nu_int(const char *p, const formatdef *f) |
| { |
| int x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromLong((long)x); |
| } |
| |
| static PyObject * |
| nu_uint(const char *p, const formatdef *f) |
| { |
| unsigned int x; |
| memcpy((char *)&x, p, sizeof x); |
| #if (SIZEOF_LONG > SIZEOF_INT) |
| return PyLong_FromLong((long)x); |
| #else |
| if (x <= ((unsigned int)LONG_MAX)) |
| return PyLong_FromLong((long)x); |
| return PyLong_FromUnsignedLong((unsigned long)x); |
| #endif |
| } |
| |
| static PyObject * |
| nu_long(const char *p, const formatdef *f) |
| { |
| long x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromLong(x); |
| } |
| |
| static PyObject * |
| nu_ulong(const char *p, const formatdef *f) |
| { |
| unsigned long x; |
| memcpy((char *)&x, p, sizeof x); |
| if (x <= LONG_MAX) |
| return PyLong_FromLong((long)x); |
| return PyLong_FromUnsignedLong(x); |
| } |
| |
| static PyObject * |
| nu_ssize_t(const char *p, const formatdef *f) |
| { |
| Py_ssize_t x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromSsize_t(x); |
| } |
| |
| static PyObject * |
| nu_size_t(const char *p, const formatdef *f) |
| { |
| size_t x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromSize_t(x); |
| } |
| |
| |
| /* Native mode doesn't support q or Q unless the platform C supports |
| long long (or, on Windows, __int64). */ |
| |
| #ifdef HAVE_LONG_LONG |
| |
| static PyObject * |
| nu_longlong(const char *p, const formatdef *f) |
| { |
| PY_LONG_LONG x; |
| memcpy((char *)&x, p, sizeof x); |
| if (x >= LONG_MIN && x <= LONG_MAX) |
| return PyLong_FromLong(Py_SAFE_DOWNCAST(x, PY_LONG_LONG, long)); |
| return PyLong_FromLongLong(x); |
| } |
| |
| static PyObject * |
| nu_ulonglong(const char *p, const formatdef *f) |
| { |
| unsigned PY_LONG_LONG x; |
| memcpy((char *)&x, p, sizeof x); |
| if (x <= LONG_MAX) |
| return PyLong_FromLong(Py_SAFE_DOWNCAST(x, unsigned PY_LONG_LONG, long)); |
| return PyLong_FromUnsignedLongLong(x); |
| } |
| |
| #endif |
| |
| static PyObject * |
| nu_bool(const char *p, const formatdef *f) |
| { |
| BOOL_TYPE x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyBool_FromLong(x != 0); |
| } |
| |
| |
| static PyObject * |
| nu_float(const char *p, const formatdef *f) |
| { |
| float x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyFloat_FromDouble((double)x); |
| } |
| |
| static PyObject * |
| nu_double(const char *p, const formatdef *f) |
| { |
| double x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyFloat_FromDouble(x); |
| } |
| |
| static PyObject * |
| nu_void_p(const char *p, const formatdef *f) |
| { |
| void *x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyLong_FromVoidPtr(x); |
| } |
| |
| 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 (!PyBytes_Check(v) || PyBytes_Size(v) != 1) { |
| PyErr_SetString(StructError, |
| "char format requires a bytes object of length 1"); |
| return -1; |
| } |
| *p = *PyBytes_AsString(v); |
| return 0; |
| } |
| |
| static int |
| np_short(char *p, PyObject *v, const formatdef *f) |
| { |
| long x; |
| short y; |
| if (get_long(v, &x) < 0) |
| return -1; |
| if (x < SHRT_MIN || x > SHRT_MAX){ |
| PyErr_SetString(StructError, |
| "short format requires " Py_STRINGIFY(SHRT_MIN) |
| " <= number <= " Py_STRINGIFY(SHRT_MAX)); |
| return -1; |
| } |
| y = (short)x; |
| memcpy(p, (char *)&y, sizeof y); |
| return 0; |
| } |
| |
| static int |
| np_ushort(char *p, PyObject *v, const formatdef *f) |
| { |
| long x; |
| unsigned short y; |
| if (get_long(v, &x) < 0) |
| return -1; |
| if (x < 0 || x > USHRT_MAX){ |
| PyErr_SetString(StructError, |
| "ushort format requires 0 <= number <= " |
| Py_STRINGIFY(USHRT_MAX)); |
| return -1; |
| } |
| y = (unsigned short)x; |
| memcpy(p, (char *)&y, sizeof y); |
| return 0; |
| } |
| |
| static int |
| np_int(char *p, PyObject *v, const formatdef *f) |
| { |
| long x; |
| int y; |
| if (get_long(v, &x) < 0) |
| return -1; |
| #if (SIZEOF_LONG > SIZEOF_INT) |
| if ((x < ((long)INT_MIN)) || (x > ((long)INT_MAX))) |
| RANGE_ERROR(x, f, 0, -1); |
| #endif |
| y = (int)x; |
| memcpy(p, (char *)&y, sizeof y); |
| return 0; |
| } |
| |
| static int |
| np_uint(char *p, PyObject *v, const formatdef *f) |
| { |
| unsigned long x; |
| unsigned int y; |
| if (get_ulong(v, &x) < 0) |
| return -1; |
| y = (unsigned int)x; |
| #if (SIZEOF_LONG > SIZEOF_INT) |
| if (x > ((unsigned long)UINT_MAX)) |
| RANGE_ERROR(y, f, 1, -1); |
| #endif |
| memcpy(p, (char *)&y, sizeof y); |
| return 0; |
| } |
| |
| static int |
| np_long(char *p, PyObject *v, const formatdef *f) |
| { |
| long x; |
| if (get_long(v, &x) < 0) |
| return -1; |
| memcpy(p, (char *)&x, sizeof 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; |
| memcpy(p, (char *)&x, sizeof x); |
| return 0; |
| } |
| |
| static int |
| np_ssize_t(char *p, PyObject *v, const formatdef *f) |
| { |
| Py_ssize_t x; |
| if (get_ssize_t(v, &x) < 0) |
| return -1; |
| memcpy(p, (char *)&x, sizeof x); |
| return 0; |
| } |
| |
| static int |
| np_size_t(char *p, PyObject *v, const formatdef *f) |
| { |
| size_t x; |
| if (get_size_t(v, &x) < 0) |
| return -1; |
| memcpy(p, (char *)&x, sizeof x); |
| return 0; |
| } |
| |
| #ifdef HAVE_LONG_LONG |
| |
| static int |
| np_longlong(char *p, PyObject *v, const formatdef *f) |
| { |
| PY_LONG_LONG x; |
| if (get_longlong(v, &x) < 0) |
| return -1; |
| memcpy(p, (char *)&x, sizeof x); |
| return 0; |
| } |
| |
| static int |
| np_ulonglong(char *p, PyObject *v, const formatdef *f) |
| { |
| unsigned PY_LONG_LONG x; |
| if (get_ulonglong(v, &x) < 0) |
| return -1; |
| memcpy(p, (char *)&x, sizeof x); |
| return 0; |
| } |
| #endif |
| |
| |
| static int |
| np_bool(char *p, PyObject *v, const formatdef *f) |
| { |
| int y; |
| BOOL_TYPE x; |
| y = PyObject_IsTrue(v); |
| if (y < 0) |
| return -1; |
| x = y; |
| memcpy(p, (char *)&x, sizeof 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 x); |
| 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; |
| |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| assert(PyLong_Check(v)); |
| x = PyLong_AsVoidPtr(v); |
| Py_DECREF(v); |
| if (x == NULL && PyErr_Occurred()) |
| return -1; |
| memcpy(p, (char *)&x, sizeof x); |
| return 0; |
| } |
| |
| static const 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}, |
| {'n', sizeof(size_t), SIZE_T_ALIGN, nu_ssize_t, np_ssize_t}, |
| {'N', sizeof(size_t), SIZE_T_ALIGN, nu_size_t, np_size_t}, |
| #ifdef HAVE_LONG_LONG |
| {'q', sizeof(PY_LONG_LONG), LONG_LONG_ALIGN, nu_longlong, np_longlong}, |
| {'Q', sizeof(PY_LONG_LONG), LONG_LONG_ALIGN, nu_ulonglong,np_ulonglong}, |
| #endif |
| {'?', sizeof(BOOL_TYPE), BOOL_ALIGN, nu_bool, np_bool}, |
| {'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} |
| }; |
| |
| /* Big-endian routines. *****************************************************/ |
| |
| static PyObject * |
| bu_int(const char *p, const formatdef *f) |
| { |
| long x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | *bytes++; |
| } while (--i > 0); |
| /* Extend the sign bit. */ |
| if (SIZEOF_LONG > f->size) |
| x |= -(x & (1L << ((8 * f->size) - 1))); |
| return PyLong_FromLong(x); |
| } |
| |
| static PyObject * |
| bu_uint(const char *p, const formatdef *f) |
| { |
| unsigned long x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | *bytes++; |
| } while (--i > 0); |
| if (x <= LONG_MAX) |
| return PyLong_FromLong((long)x); |
| return PyLong_FromUnsignedLong(x); |
| } |
| |
| static PyObject * |
| bu_longlong(const char *p, const formatdef *f) |
| { |
| #ifdef HAVE_LONG_LONG |
| PY_LONG_LONG x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | *bytes++; |
| } while (--i > 0); |
| /* Extend the sign bit. */ |
| if (SIZEOF_LONG_LONG > f->size) |
| x |= -(x & ((PY_LONG_LONG)1 << ((8 * f->size) - 1))); |
| if (x >= LONG_MIN && x <= LONG_MAX) |
| return PyLong_FromLong(Py_SAFE_DOWNCAST(x, PY_LONG_LONG, long)); |
| return PyLong_FromLongLong(x); |
| #else |
| return _PyLong_FromByteArray((const unsigned char *)p, |
| 8, |
| 0, /* little-endian */ |
| 1 /* signed */); |
| #endif |
| } |
| |
| static PyObject * |
| bu_ulonglong(const char *p, const formatdef *f) |
| { |
| #ifdef HAVE_LONG_LONG |
| unsigned PY_LONG_LONG x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | *bytes++; |
| } while (--i > 0); |
| if (x <= LONG_MAX) |
| return PyLong_FromLong(Py_SAFE_DOWNCAST(x, unsigned PY_LONG_LONG, long)); |
| return PyLong_FromUnsignedLongLong(x); |
| #else |
| return _PyLong_FromByteArray((const unsigned char *)p, |
| 8, |
| 0, /* little-endian */ |
| 0 /* signed */); |
| #endif |
| } |
| |
| static PyObject * |
| bu_float(const char *p, const formatdef *f) |
| { |
| return unpack_float(p, 0); |
| } |
| |
| static PyObject * |
| bu_double(const char *p, const formatdef *f) |
| { |
| return unpack_double(p, 0); |
| } |
| |
| static PyObject * |
| bu_bool(const char *p, const formatdef *f) |
| { |
| char x; |
| memcpy((char *)&x, p, sizeof x); |
| return PyBool_FromLong(x != 0); |
| } |
| |
| static int |
| bp_int(char *p, PyObject *v, const formatdef *f) |
| { |
| long x; |
| Py_ssize_t i; |
| if (get_long(v, &x) < 0) |
| return -1; |
| i = f->size; |
| if (i != SIZEOF_LONG) { |
| if ((i == 2) && (x < -32768 || x > 32767)) |
| RANGE_ERROR(x, f, 0, 0xffffL); |
| #if (SIZEOF_LONG != 4) |
| else if ((i == 4) && (x < -2147483648L || x > 2147483647L)) |
| RANGE_ERROR(x, f, 0, 0xffffffffL); |
| #endif |
| } |
| 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; |
| Py_ssize_t i; |
| if (get_ulong(v, &x) < 0) |
| return -1; |
| i = f->size; |
| if (i != SIZEOF_LONG) { |
| unsigned long maxint = 1; |
| maxint <<= (unsigned long)(i * 8); |
| if (x >= maxint) |
| RANGE_ERROR(x, f, 1, maxint - 1); |
| } |
| do { |
| p[--i] = (char)x; |
| x >>= 8; |
| } while (i > 0); |
| return 0; |
| } |
| |
| static int |
| bp_longlong(char *p, PyObject *v, const formatdef *f) |
| { |
| int res; |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| res = _PyLong_AsByteArray((PyLongObject *)v, |
| (unsigned char *)p, |
| 8, |
| 0, /* little_endian */ |
| 1 /* signed */); |
| Py_DECREF(v); |
| return res; |
| } |
| |
| static int |
| bp_ulonglong(char *p, PyObject *v, const formatdef *f) |
| { |
| int res; |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| res = _PyLong_AsByteArray((PyLongObject *)v, |
| (unsigned char *)p, |
| 8, |
| 0, /* little_endian */ |
| 0 /* signed */); |
| Py_DECREF(v); |
| return res; |
| } |
| |
| 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 _PyFloat_Pack4(x, (unsigned char *)p, 0); |
| } |
| |
| 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 _PyFloat_Pack8(x, (unsigned char *)p, 0); |
| } |
| |
| static int |
| bp_bool(char *p, PyObject *v, const formatdef *f) |
| { |
| int y; |
| y = PyObject_IsTrue(v); |
| if (y < 0) |
| return -1; |
| *p = (char)y; |
| return 0; |
| } |
| |
| static formatdef bigendian_table[] = { |
| {'x', 1, 0, NULL}, |
| {'b', 1, 0, nu_byte, np_byte}, |
| {'B', 1, 0, nu_ubyte, np_ubyte}, |
| {'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}, |
| {'q', 8, 0, bu_longlong, bp_longlong}, |
| {'Q', 8, 0, bu_ulonglong, bp_ulonglong}, |
| {'?', 1, 0, bu_bool, bp_bool}, |
| {'f', 4, 0, bu_float, bp_float}, |
| {'d', 8, 0, bu_double, bp_double}, |
| {0} |
| }; |
| |
| /* Little-endian routines. *****************************************************/ |
| |
| static PyObject * |
| lu_int(const char *p, const formatdef *f) |
| { |
| long x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | bytes[--i]; |
| } while (i > 0); |
| /* Extend the sign bit. */ |
| if (SIZEOF_LONG > f->size) |
| x |= -(x & (1L << ((8 * f->size) - 1))); |
| return PyLong_FromLong(x); |
| } |
| |
| static PyObject * |
| lu_uint(const char *p, const formatdef *f) |
| { |
| unsigned long x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | bytes[--i]; |
| } while (i > 0); |
| if (x <= LONG_MAX) |
| return PyLong_FromLong((long)x); |
| return PyLong_FromUnsignedLong((long)x); |
| } |
| |
| static PyObject * |
| lu_longlong(const char *p, const formatdef *f) |
| { |
| #ifdef HAVE_LONG_LONG |
| PY_LONG_LONG x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | bytes[--i]; |
| } while (i > 0); |
| /* Extend the sign bit. */ |
| if (SIZEOF_LONG_LONG > f->size) |
| x |= -(x & ((PY_LONG_LONG)1 << ((8 * f->size) - 1))); |
| if (x >= LONG_MIN && x <= LONG_MAX) |
| return PyLong_FromLong(Py_SAFE_DOWNCAST(x, PY_LONG_LONG, long)); |
| return PyLong_FromLongLong(x); |
| #else |
| return _PyLong_FromByteArray((const unsigned char *)p, |
| 8, |
| 1, /* little-endian */ |
| 1 /* signed */); |
| #endif |
| } |
| |
| static PyObject * |
| lu_ulonglong(const char *p, const formatdef *f) |
| { |
| #ifdef HAVE_LONG_LONG |
| unsigned PY_LONG_LONG x = 0; |
| Py_ssize_t i = f->size; |
| const unsigned char *bytes = (const unsigned char *)p; |
| do { |
| x = (x<<8) | bytes[--i]; |
| } while (i > 0); |
| if (x <= LONG_MAX) |
| return PyLong_FromLong(Py_SAFE_DOWNCAST(x, unsigned PY_LONG_LONG, long)); |
| return PyLong_FromUnsignedLongLong(x); |
| #else |
| return _PyLong_FromByteArray((const unsigned char *)p, |
| 8, |
| 1, /* little-endian */ |
| 0 /* signed */); |
| #endif |
| } |
| |
| static PyObject * |
| lu_float(const char *p, const formatdef *f) |
| { |
| return unpack_float(p, 1); |
| } |
| |
| static PyObject * |
| lu_double(const char *p, const formatdef *f) |
| { |
| return unpack_double(p, 1); |
| } |
| |
| static int |
| lp_int(char *p, PyObject *v, const formatdef *f) |
| { |
| long x; |
| Py_ssize_t i; |
| if (get_long(v, &x) < 0) |
| return -1; |
| i = f->size; |
| if (i != SIZEOF_LONG) { |
| if ((i == 2) && (x < -32768 || x > 32767)) |
| RANGE_ERROR(x, f, 0, 0xffffL); |
| #if (SIZEOF_LONG != 4) |
| else if ((i == 4) && (x < -2147483648L || x > 2147483647L)) |
| RANGE_ERROR(x, f, 0, 0xffffffffL); |
| #endif |
| } |
| 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; |
| Py_ssize_t i; |
| if (get_ulong(v, &x) < 0) |
| return -1; |
| i = f->size; |
| if (i != SIZEOF_LONG) { |
| unsigned long maxint = 1; |
| maxint <<= (unsigned long)(i * 8); |
| if (x >= maxint) |
| RANGE_ERROR(x, f, 1, maxint - 1); |
| } |
| do { |
| *p++ = (char)x; |
| x >>= 8; |
| } while (--i > 0); |
| return 0; |
| } |
| |
| static int |
| lp_longlong(char *p, PyObject *v, const formatdef *f) |
| { |
| int res; |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| res = _PyLong_AsByteArray((PyLongObject*)v, |
| (unsigned char *)p, |
| 8, |
| 1, /* little_endian */ |
| 1 /* signed */); |
| Py_DECREF(v); |
| return res; |
| } |
| |
| static int |
| lp_ulonglong(char *p, PyObject *v, const formatdef *f) |
| { |
| int res; |
| v = get_pylong(v); |
| if (v == NULL) |
| return -1; |
| res = _PyLong_AsByteArray((PyLongObject*)v, |
| (unsigned char *)p, |
| 8, |
| 1, /* little_endian */ |
| 0 /* signed */); |
| Py_DECREF(v); |
| return res; |
| } |
| |
| 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 _PyFloat_Pack4(x, (unsigned char *)p, 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 _PyFloat_Pack8(x, (unsigned char *)p, 1); |
| } |
| |
| static formatdef lilendian_table[] = { |
| {'x', 1, 0, NULL}, |
| {'b', 1, 0, nu_byte, np_byte}, |
| {'B', 1, 0, nu_ubyte, np_ubyte}, |
| {'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}, |
| {'q', 8, 0, lu_longlong, lp_longlong}, |
| {'Q', 8, 0, lu_ulonglong, lp_ulonglong}, |
| {'?', 1, 0, bu_bool, bp_bool}, /* Std rep not endian dep, |
| but potentially different from native rep -- reuse bx_bool funcs. */ |
| {'f', 4, 0, lu_float, lp_float}, |
| {'d', 8, 0, lu_double, lp_double}, |
| {0} |
| }; |
| |
| |
| static const formatdef * |
| whichtable(const 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 alignment! */ |
| #if PY_LITTLE_ENDIAN |
| return lilendian_table; |
| #else |
| return bigendian_table; |
| #endif |
| } |
| 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. Return -1 on overflow. */ |
| |
| static Py_ssize_t |
| align(Py_ssize_t size, char c, const formatdef *e) |
| { |
| Py_ssize_t extra; |
| |
| if (e->format == c) { |
| if (e->alignment && size > 0) { |
| extra = (e->alignment - 1) - (size - 1) % (e->alignment); |
| if (extra > PY_SSIZE_T_MAX - size) |
| return -1; |
| size += extra; |
| } |
| } |
| return size; |
| } |
| |
| /* |
| * Struct object implementation. |
| */ |
| |
| /* calculate the size of a format string */ |
| |
| static int |
| prepare_s(PyStructObject *self) |
| { |
| const formatdef *f; |
| const formatdef *e; |
| formatcode *codes; |
| |
| const char *s; |
| const char *fmt; |
| char c; |
| Py_ssize_t size, len, num, itemsize; |
| size_t ncodes; |
| |
| fmt = PyBytes_AS_STRING(self->s_format); |
| |
| f = whichtable(&fmt); |
| |
| s = fmt; |
| size = 0; |
| len = 0; |
| ncodes = 0; |
| while ((c = *s++) != '\0') { |
| if (Py_ISSPACE(Py_CHARMASK(c))) |
| continue; |
| if ('0' <= c && c <= '9') { |
| num = c - '0'; |
| while ('0' <= (c = *s++) && c <= '9') { |
| /* overflow-safe version of |
| if (num*10 + (c - '0') > PY_SSIZE_T_MAX) { ... } */ |
| if (num >= PY_SSIZE_T_MAX / 10 && ( |
| num > PY_SSIZE_T_MAX / 10 || |
| (c - '0') > PY_SSIZE_T_MAX % 10)) |
| goto overflow; |
| num = num*10 + (c - '0'); |
| } |
| if (c == '\0') { |
| PyErr_SetString(StructError, |
| "repeat count given without format specifier"); |
| return -1; |
| } |
| } |
| else |
| num = 1; |
| |
| e = getentry(c, f); |
| if (e == NULL) |
| return -1; |
| |
| switch (c) { |
| case 's': /* fall through */ |
| case 'p': len++; ncodes++; break; |
| case 'x': break; |
| default: len += num; if (num) ncodes++; break; |
| } |
| |
| itemsize = e->size; |
| size = align(size, c, e); |
| if (size == -1) |
| goto overflow; |
| |
| /* if (size + num * itemsize > PY_SSIZE_T_MAX) { ... } */ |
| if (num > (PY_SSIZE_T_MAX - size) / itemsize) |
| goto overflow; |
| size += num * itemsize; |
| } |
| |
| /* check for overflow */ |
| if ((ncodes + 1) > ((size_t)PY_SSIZE_T_MAX / sizeof(formatcode))) { |
| PyErr_NoMemory(); |
| return -1; |
| } |
| |
| self->s_size = size; |
| self->s_len = len; |
| codes = PyMem_MALLOC((ncodes + 1) * sizeof(formatcode)); |
| if (codes == NULL) { |
| PyErr_NoMemory(); |
| return -1; |
| } |
| /* Free any s_codes value left over from a previous initialization. */ |
| if (self->s_codes != NULL) |
| PyMem_FREE(self->s_codes); |
| self->s_codes = codes; |
| |
| s = fmt; |
| size = 0; |
| while ((c = *s++) != '\0') { |
| if (Py_ISSPACE(Py_CHARMASK(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); |
| |
| size = align(size, c, e); |
| if (c == 's' || c == 'p') { |
| codes->offset = size; |
| codes->size = num; |
| codes->fmtdef = e; |
| codes->repeat = 1; |
| codes++; |
| size += num; |
| } else if (c == 'x') { |
| size += num; |
| } else if (num) { |
| codes->offset = size; |
| codes->size = e->size; |
| codes->fmtdef = e; |
| codes->repeat = num; |
| codes++; |
| size += e->size * num; |
| } |
| } |
| codes->fmtdef = NULL; |
| codes->offset = size; |
| codes->size = 0; |
| codes->repeat = 0; |
| |
| return 0; |
| |
| overflow: |
| PyErr_SetString(StructError, |
| "total struct size too long"); |
| return -1; |
| } |
| |
| static PyObject * |
| s_new(PyTypeObject *type, PyObject *args, PyObject *kwds) |
| { |
| PyObject *self; |
| |
| assert(type != NULL && type->tp_alloc != NULL); |
| |
| self = type->tp_alloc(type, 0); |
| if (self != NULL) { |
| PyStructObject *s = (PyStructObject*)self; |
| Py_INCREF(Py_None); |
| s->s_format = Py_None; |
| s->s_codes = NULL; |
| s->s_size = -1; |
| s->s_len = -1; |
| } |
| return self; |
| } |
| |
| static int |
| s_init(PyObject *self, PyObject *args, PyObject *kwds) |
| { |
| PyStructObject *soself = (PyStructObject *)self; |
| PyObject *o_format = NULL; |
| int ret = 0; |
| static char *kwlist[] = {"format", 0}; |
| |
| assert(PyStruct_Check(self)); |
| |
| if (!PyArg_ParseTupleAndKeywords(args, kwds, "O:Struct", kwlist, |
| &o_format)) |
| return -1; |
| |
| if (PyUnicode_Check(o_format)) { |
| o_format = PyUnicode_AsASCIIString(o_format); |
| if (o_format == NULL) |
| return -1; |
| } |
| /* XXX support buffer interface, too */ |
| else { |
| Py_INCREF(o_format); |
| } |
| |
| if (!PyBytes_Check(o_format)) { |
| Py_DECREF(o_format); |
| PyErr_Format(PyExc_TypeError, |
| "Struct() argument 1 must be a bytes object, not %.200s", |
| Py_TYPE(o_format)->tp_name); |
| return -1; |
| } |
| |
| Py_XSETREF(soself->s_format, o_format); |
| |
| ret = prepare_s(soself); |
| return ret; |
| } |
| |
| static void |
| s_dealloc(PyStructObject *s) |
| { |
| if (s->weakreflist != NULL) |
| PyObject_ClearWeakRefs((PyObject *)s); |
| if (s->s_codes != NULL) { |
| PyMem_FREE(s->s_codes); |
| } |
| Py_XDECREF(s->s_format); |
| Py_TYPE(s)->tp_free((PyObject *)s); |
| } |
| |
| static PyObject * |
| s_unpack_internal(PyStructObject *soself, const char *startfrom) { |
| formatcode *code; |
| Py_ssize_t i = 0; |
| PyObject *result = PyTuple_New(soself->s_len); |
| if (result == NULL) |
| return NULL; |
| |
| for (code = soself->s_codes; code->fmtdef != NULL; code++) { |
| const formatdef *e = code->fmtdef; |
| const char *res = startfrom + code->offset; |
| Py_ssize_t j = code->repeat; |
| while (j--) { |
| PyObject *v; |
| if (e->format == 's') { |
| v = PyBytes_FromStringAndSize(res, code->size); |
| } else if (e->format == 'p') { |
| Py_ssize_t n = *(unsigned char*)res; |
| if (n >= code->size) |
| n = code->size - 1; |
| v = PyBytes_FromStringAndSize(res + 1, n); |
| } else { |
| v = e->unpack(res, e); |
| } |
| if (v == NULL) |
| goto fail; |
| PyTuple_SET_ITEM(result, i++, v); |
| res += code->size; |
| } |
| } |
| |
| return result; |
| fail: |
| Py_DECREF(result); |
| return NULL; |
| } |
| |
| |
| PyDoc_STRVAR(s_unpack__doc__, |
| "S.unpack(buffer) -> (v1, v2, ...)\n\ |
| \n\ |
| Return a tuple containing values unpacked according to the format\n\ |
| string S.format. Requires len(buffer) == S.size. See help(struct)\n\ |
| for more on format strings."); |
| |
| static PyObject * |
| s_unpack(PyObject *self, PyObject *input) |
| { |
| Py_buffer vbuf; |
| PyObject *result; |
| PyStructObject *soself = (PyStructObject *)self; |
| |
| assert(PyStruct_Check(self)); |
| assert(soself->s_codes != NULL); |
| if (PyObject_GetBuffer(input, &vbuf, PyBUF_SIMPLE) < 0) |
| return NULL; |
| if (vbuf.len != soself->s_size) { |
| PyErr_Format(StructError, |
| "unpack requires a bytes object of length %zd", |
| soself->s_size); |
| PyBuffer_Release(&vbuf); |
| return NULL; |
| } |
| result = s_unpack_internal(soself, vbuf.buf); |
| PyBuffer_Release(&vbuf); |
| return result; |
| } |
| |
| PyDoc_STRVAR(s_unpack_from__doc__, |
| "S.unpack_from(buffer, offset=0) -> (v1, v2, ...)\n\ |
| \n\ |
| Return a tuple containing values unpacked according to the format\n\ |
| string S.format. Requires len(buffer[offset:]) >= S.size. See\n\ |
| help(struct) for more on format strings."); |
| |
| static PyObject * |
| s_unpack_from(PyObject *self, PyObject *args, PyObject *kwds) |
| { |
| static char *kwlist[] = {"buffer", "offset", 0}; |
| |
| PyObject *input; |
| Py_ssize_t offset = 0; |
| Py_buffer vbuf; |
| PyObject *result; |
| PyStructObject *soself = (PyStructObject *)self; |
| |
| assert(PyStruct_Check(self)); |
| assert(soself->s_codes != NULL); |
| |
| if (!PyArg_ParseTupleAndKeywords(args, kwds, |
| "O|n:unpack_from", kwlist, |
| &input, &offset)) |
| return NULL; |
| if (PyObject_GetBuffer(input, &vbuf, PyBUF_SIMPLE) < 0) |
| return NULL; |
| if (offset < 0) |
| offset += vbuf.len; |
| if (offset < 0 || vbuf.len - offset < soself->s_size) { |
| PyErr_Format(StructError, |
| "unpack_from requires a buffer of at least %zd bytes", |
| soself->s_size); |
| PyBuffer_Release(&vbuf); |
| return NULL; |
| } |
| result = s_unpack_internal(soself, (char*)vbuf.buf + offset); |
| PyBuffer_Release(&vbuf); |
| return result; |
| } |
| |
| |
| /* Unpack iterator type */ |
| |
| typedef struct { |
| PyObject_HEAD |
| PyStructObject *so; |
| Py_buffer buf; |
| Py_ssize_t index; |
| } unpackiterobject; |
| |
| static void |
| unpackiter_dealloc(unpackiterobject *self) |
| { |
| Py_XDECREF(self->so); |
| PyBuffer_Release(&self->buf); |
| PyObject_GC_Del(self); |
| } |
| |
| static int |
| unpackiter_traverse(unpackiterobject *self, visitproc visit, void *arg) |
| { |
| Py_VISIT(self->so); |
| Py_VISIT(self->buf.obj); |
| return 0; |
| } |
| |
| static PyObject * |
| unpackiter_len(unpackiterobject *self) |
| { |
| Py_ssize_t len; |
| if (self->so == NULL) |
| len = 0; |
| else |
| len = (self->buf.len - self->index) / self->so->s_size; |
| return PyLong_FromSsize_t(len); |
| } |
| |
| static PyMethodDef unpackiter_methods[] = { |
| {"__length_hint__", (PyCFunction) unpackiter_len, METH_NOARGS, NULL}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| static PyObject * |
| unpackiter_iternext(unpackiterobject *self) |
| { |
| PyObject *result; |
| if (self->so == NULL) |
| return NULL; |
| if (self->index >= self->buf.len) { |
| /* Iterator exhausted */ |
| Py_CLEAR(self->so); |
| PyBuffer_Release(&self->buf); |
| return NULL; |
| } |
| assert(self->index + self->so->s_size <= self->buf.len); |
| result = s_unpack_internal(self->so, |
| (char*) self->buf.buf + self->index); |
| self->index += self->so->s_size; |
| return result; |
| } |
| |
| static PyTypeObject unpackiter_type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "unpack_iterator", /* tp_name */ |
| sizeof(unpackiterobject), /* tp_basicsize */ |
| 0, /* tp_itemsize */ |
| (destructor)unpackiter_dealloc, /* tp_dealloc */ |
| 0, /* tp_print */ |
| 0, /* tp_getattr */ |
| 0, /* tp_setattr */ |
| 0, /* tp_reserved */ |
| 0, /* tp_repr */ |
| 0, /* tp_as_number */ |
| 0, /* tp_as_sequence */ |
| 0, /* tp_as_mapping */ |
| 0, /* tp_hash */ |
| 0, /* tp_call */ |
| 0, /* tp_str */ |
| PyObject_GenericGetAttr, /* tp_getattro */ |
| 0, /* tp_setattro */ |
| 0, /* tp_as_buffer */ |
| Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, /* tp_flags */ |
| 0, /* tp_doc */ |
| (traverseproc)unpackiter_traverse, /* tp_traverse */ |
| 0, /* tp_clear */ |
| 0, /* tp_richcompare */ |
| 0, /* tp_weaklistoffset */ |
| PyObject_SelfIter, /* tp_iter */ |
| (iternextfunc)unpackiter_iternext, /* tp_iternext */ |
| unpackiter_methods /* tp_methods */ |
| }; |
| |
| PyDoc_STRVAR(s_iter_unpack__doc__, |
| "S.iter_unpack(buffer) -> iterator(v1, v2, ...)\n\ |
| \n\ |
| Return an iterator yielding tuples unpacked from the given bytes\n\ |
| source, like a repeated invocation of unpack_from(). Requires\n\ |
| that the bytes length be a multiple of the struct size."); |
| |
| static PyObject * |
| s_iter_unpack(PyObject *_so, PyObject *input) |
| { |
| PyStructObject *so = (PyStructObject *) _so; |
| unpackiterobject *self; |
| |
| assert(PyStruct_Check(_so)); |
| assert(so->s_codes != NULL); |
| |
| if (so->s_size == 0) { |
| PyErr_Format(StructError, |
| "cannot iteratively unpack with a struct of length 0"); |
| return NULL; |
| } |
| |
| self = (unpackiterobject *) PyType_GenericAlloc(&unpackiter_type, 0); |
| if (self == NULL) |
| return NULL; |
| |
| if (PyObject_GetBuffer(input, &self->buf, PyBUF_SIMPLE) < 0) { |
| Py_DECREF(self); |
| return NULL; |
| } |
| if (self->buf.len % so->s_size != 0) { |
| PyErr_Format(StructError, |
| "iterative unpacking requires a bytes length " |
| "multiple of %zd", |
| so->s_size); |
| Py_DECREF(self); |
| return NULL; |
| } |
| Py_INCREF(so); |
| self->so = so; |
| self->index = 0; |
| return (PyObject *) self; |
| } |
| |
| |
| /* |
| * Guts of the pack function. |
| * |
| * Takes a struct object, a tuple of arguments, and offset in that tuple of |
| * argument for where to start processing the arguments for packing, and a |
| * character buffer for writing the packed string. The caller must insure |
| * that the buffer may contain the required length for packing the arguments. |
| * 0 is returned on success, 1 is returned if there is an error. |
| * |
| */ |
| static int |
| s_pack_internal(PyStructObject *soself, PyObject *args, int offset, char* buf) |
| { |
| formatcode *code; |
| /* XXX(nnorwitz): why does i need to be a local? can we use |
| the offset parameter or do we need the wider width? */ |
| Py_ssize_t i; |
| |
| memset(buf, '\0', soself->s_size); |
| i = offset; |
| for (code = soself->s_codes; code->fmtdef != NULL; code++) { |
| const formatdef *e = code->fmtdef; |
| char *res = buf + code->offset; |
| Py_ssize_t j = code->repeat; |
| while (j--) { |
| PyObject *v = PyTuple_GET_ITEM(args, i++); |
| if (e->format == 's') { |
| Py_ssize_t n; |
| int isstring; |
| void *p; |
| isstring = PyBytes_Check(v); |
| if (!isstring && !PyByteArray_Check(v)) { |
| PyErr_SetString(StructError, |
| "argument for 's' must be a bytes object"); |
| return -1; |
| } |
| if (isstring) { |
| n = PyBytes_GET_SIZE(v); |
| p = PyBytes_AS_STRING(v); |
| } |
| else { |
| n = PyByteArray_GET_SIZE(v); |
| p = PyByteArray_AS_STRING(v); |
| } |
| if (n > code->size) |
| n = code->size; |
| if (n > 0) |
| memcpy(res, p, n); |
| } else if (e->format == 'p') { |
| Py_ssize_t n; |
| int isstring; |
| void *p; |
| isstring = PyBytes_Check(v); |
| if (!isstring && !PyByteArray_Check(v)) { |
| PyErr_SetString(StructError, |
| "argument for 'p' must be a bytes object"); |
| return -1; |
| } |
| if (isstring) { |
| n = PyBytes_GET_SIZE(v); |
| p = PyBytes_AS_STRING(v); |
| } |
| else { |
| n = PyByteArray_GET_SIZE(v); |
| p = PyByteArray_AS_STRING(v); |
| } |
| if (n > (code->size - 1)) |
| n = code->size - 1; |
| if (n > 0) |
| memcpy(res + 1, p, n); |
| if (n > 255) |
| n = 255; |
| *res = Py_SAFE_DOWNCAST(n, Py_ssize_t, unsigned char); |
| } else { |
| if (e->pack(res, v, e) < 0) { |
| if (PyLong_Check(v) && PyErr_ExceptionMatches(PyExc_OverflowError)) |
| PyErr_SetString(StructError, |
| "int too large to convert"); |
| return -1; |
| } |
| } |
| res += code->size; |
| } |
| } |
| |
| /* Success */ |
| return 0; |
| } |
| |
| |
| PyDoc_STRVAR(s_pack__doc__, |
| "S.pack(v1, v2, ...) -> bytes\n\ |
| \n\ |
| Return a bytes object containing values v1, v2, ... packed according\n\ |
| to the format string S.format. See help(struct) for more on format\n\ |
| strings."); |
| |
| static PyObject * |
| s_pack(PyObject *self, PyObject *args) |
| { |
| PyStructObject *soself; |
| PyObject *result; |
| |
| /* Validate arguments. */ |
| soself = (PyStructObject *)self; |
| assert(PyStruct_Check(self)); |
| assert(soself->s_codes != NULL); |
| if (PyTuple_GET_SIZE(args) != soself->s_len) |
| { |
| PyErr_Format(StructError, |
| "pack expected %zd items for packing (got %zd)", soself->s_len, PyTuple_GET_SIZE(args)); |
| return NULL; |
| } |
| |
| /* Allocate a new string */ |
| result = PyBytes_FromStringAndSize((char *)NULL, soself->s_size); |
| if (result == NULL) |
| return NULL; |
| |
| /* Call the guts */ |
| if ( s_pack_internal(soself, args, 0, PyBytes_AS_STRING(result)) != 0 ) { |
| Py_DECREF(result); |
| return NULL; |
| } |
| |
| return result; |
| } |
| |
| PyDoc_STRVAR(s_pack_into__doc__, |
| "S.pack_into(buffer, offset, v1, v2, ...)\n\ |
| \n\ |
| Pack the values v1, v2, ... according to the format string S.format\n\ |
| and write the packed bytes into the writable buffer buf starting at\n\ |
| offset. Note that the offset is a required argument. See\n\ |
| help(struct) for more on format strings."); |
| |
| static PyObject * |
| s_pack_into(PyObject *self, PyObject *args) |
| { |
| PyStructObject *soself; |
| Py_buffer buffer; |
| Py_ssize_t offset; |
| |
| /* Validate arguments. +1 is for the first arg as buffer. */ |
| soself = (PyStructObject *)self; |
| assert(PyStruct_Check(self)); |
| assert(soself->s_codes != NULL); |
| if (PyTuple_GET_SIZE(args) != (soself->s_len + 2)) |
| { |
| if (PyTuple_GET_SIZE(args) == 0) { |
| PyErr_Format(StructError, |
| "pack_into expected buffer argument"); |
| } |
| else if (PyTuple_GET_SIZE(args) == 1) { |
| PyErr_Format(StructError, |
| "pack_into expected offset argument"); |
| } |
| else { |
| PyErr_Format(StructError, |
| "pack_into expected %zd items for packing (got %zd)", |
| soself->s_len, (PyTuple_GET_SIZE(args) - 2)); |
| } |
| return NULL; |
| } |
| |
| /* Extract a writable memory buffer from the first argument */ |
| if (!PyArg_Parse(PyTuple_GET_ITEM(args, 0), "w*", &buffer)) |
| return NULL; |
| assert(buffer.len >= 0); |
| |
| /* Extract the offset from the first argument */ |
| offset = PyNumber_AsSsize_t(PyTuple_GET_ITEM(args, 1), PyExc_IndexError); |
| if (offset == -1 && PyErr_Occurred()) { |
| PyBuffer_Release(&buffer); |
| return NULL; |
| } |
| |
| /* Support negative offsets. */ |
| if (offset < 0) |
| offset += buffer.len; |
| |
| /* Check boundaries */ |
| if (offset < 0 || (buffer.len - offset) < soself->s_size) { |
| PyErr_Format(StructError, |
| "pack_into requires a buffer of at least %zd bytes", |
| soself->s_size); |
| PyBuffer_Release(&buffer); |
| return NULL; |
| } |
| |
| /* Call the guts */ |
| if (s_pack_internal(soself, args, 2, (char*)buffer.buf + offset) != 0) { |
| PyBuffer_Release(&buffer); |
| return NULL; |
| } |
| |
| PyBuffer_Release(&buffer); |
| Py_RETURN_NONE; |
| } |
| |
| static PyObject * |
| s_get_format(PyStructObject *self, void *unused) |
| { |
| Py_INCREF(self->s_format); |
| return self->s_format; |
| } |
| |
| static PyObject * |
| s_get_size(PyStructObject *self, void *unused) |
| { |
| return PyLong_FromSsize_t(self->s_size); |
| } |
| |
| PyDoc_STRVAR(s_sizeof__doc__, |
| "S.__sizeof__() -> size of S in memory, in bytes"); |
| |
| static PyObject * |
| s_sizeof(PyStructObject *self, void *unused) |
| { |
| Py_ssize_t size; |
| formatcode *code; |
| |
| size = _PyObject_SIZE(Py_TYPE(self)) + sizeof(formatcode); |
| for (code = self->s_codes; code->fmtdef != NULL; code++) |
| size += sizeof(formatcode); |
| return PyLong_FromSsize_t(size); |
| } |
| |
| /* List of functions */ |
| |
| static struct PyMethodDef s_methods[] = { |
| {"iter_unpack", s_iter_unpack, METH_O, s_iter_unpack__doc__}, |
| {"pack", s_pack, METH_VARARGS, s_pack__doc__}, |
| {"pack_into", s_pack_into, METH_VARARGS, s_pack_into__doc__}, |
| {"unpack", s_unpack, METH_O, s_unpack__doc__}, |
| {"unpack_from", (PyCFunction)s_unpack_from, METH_VARARGS|METH_KEYWORDS, |
| s_unpack_from__doc__}, |
| {"__sizeof__", (PyCFunction)s_sizeof, METH_NOARGS, s_sizeof__doc__}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| PyDoc_STRVAR(s__doc__, |
| "Struct(fmt) --> compiled struct object\n" |
| "\n" |
| "Return a new Struct object which writes and reads binary data according to\n" |
| "the format string fmt. See help(struct) for more on format strings."); |
| |
| #define OFF(x) offsetof(PyStructObject, x) |
| |
| static PyGetSetDef s_getsetlist[] = { |
| {"format", (getter)s_get_format, (setter)NULL, "struct format string", NULL}, |
| {"size", (getter)s_get_size, (setter)NULL, "struct size in bytes", NULL}, |
| {NULL} /* sentinel */ |
| }; |
| |
| static |
| PyTypeObject PyStructType = { |
| PyVarObject_HEAD_INIT(NULL, 0) |
| "Struct", |
| sizeof(PyStructObject), |
| 0, |
| (destructor)s_dealloc, /* tp_dealloc */ |
| 0, /* tp_print */ |
| 0, /* tp_getattr */ |
| 0, /* tp_setattr */ |
| 0, /* tp_reserved */ |
| 0, /* tp_repr */ |
| 0, /* tp_as_number */ |
| 0, /* tp_as_sequence */ |
| 0, /* tp_as_mapping */ |
| 0, /* tp_hash */ |
| 0, /* tp_call */ |
| 0, /* tp_str */ |
| PyObject_GenericGetAttr, /* tp_getattro */ |
| PyObject_GenericSetAttr, /* tp_setattro */ |
| 0, /* tp_as_buffer */ |
| Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */ |
| s__doc__, /* tp_doc */ |
| 0, /* tp_traverse */ |
| 0, /* tp_clear */ |
| 0, /* tp_richcompare */ |
| offsetof(PyStructObject, weakreflist), /* tp_weaklistoffset */ |
| 0, /* tp_iter */ |
| 0, /* tp_iternext */ |
| s_methods, /* tp_methods */ |
| NULL, /* tp_members */ |
| s_getsetlist, /* tp_getset */ |
| 0, /* tp_base */ |
| 0, /* tp_dict */ |
| 0, /* tp_descr_get */ |
| 0, /* tp_descr_set */ |
| 0, /* tp_dictoffset */ |
| s_init, /* tp_init */ |
| PyType_GenericAlloc,/* tp_alloc */ |
| s_new, /* tp_new */ |
| PyObject_Del, /* tp_free */ |
| }; |
| |
| |
| /* ---- Standalone functions ---- */ |
| |
| #define MAXCACHE 100 |
| static PyObject *cache = NULL; |
| |
| static PyObject * |
| cache_struct(PyObject *fmt) |
| { |
| PyObject * s_object; |
| |
| if (cache == NULL) { |
| cache = PyDict_New(); |
| if (cache == NULL) |
| return NULL; |
| } |
| |
| s_object = PyDict_GetItem(cache, fmt); |
| if (s_object != NULL) { |
| Py_INCREF(s_object); |
| return s_object; |
| } |
| |
| s_object = PyObject_CallFunctionObjArgs((PyObject *)(&PyStructType), fmt, NULL); |
| if (s_object != NULL) { |
| if (PyDict_Size(cache) >= MAXCACHE) |
| PyDict_Clear(cache); |
| /* Attempt to cache the result */ |
| if (PyDict_SetItem(cache, fmt, s_object) == -1) |
| PyErr_Clear(); |
| } |
| return s_object; |
| } |
| |
| PyDoc_STRVAR(clearcache_doc, |
| "Clear the internal cache."); |
| |
| static PyObject * |
| clearcache(PyObject *self) |
| { |
| Py_CLEAR(cache); |
| Py_RETURN_NONE; |
| } |
| |
| PyDoc_STRVAR(calcsize_doc, |
| "calcsize(fmt) -> integer\n\ |
| \n\ |
| Return size in bytes of the struct described by the format string fmt."); |
| |
| static PyObject * |
| calcsize(PyObject *self, PyObject *fmt) |
| { |
| Py_ssize_t n; |
| PyObject *s_object = cache_struct(fmt); |
| if (s_object == NULL) |
| return NULL; |
| n = ((PyStructObject *)s_object)->s_size; |
| Py_DECREF(s_object); |
| return PyLong_FromSsize_t(n); |
| } |
| |
| PyDoc_STRVAR(pack_doc, |
| "pack(fmt, v1, v2, ...) -> bytes\n\ |
| \n\ |
| Return a bytes object containing the values v1, v2, ... packed according\n\ |
| to the format string fmt. See help(struct) for more on format strings."); |
| |
| static PyObject * |
| pack(PyObject *self, PyObject *args) |
| { |
| PyObject *s_object, *fmt, *newargs, *result; |
| Py_ssize_t n = PyTuple_GET_SIZE(args); |
| |
| if (n == 0) { |
| PyErr_SetString(PyExc_TypeError, "missing format argument"); |
| return NULL; |
| } |
| fmt = PyTuple_GET_ITEM(args, 0); |
| newargs = PyTuple_GetSlice(args, 1, n); |
| if (newargs == NULL) |
| return NULL; |
| |
| s_object = cache_struct(fmt); |
| if (s_object == NULL) { |
| Py_DECREF(newargs); |
| return NULL; |
| } |
| result = s_pack(s_object, newargs); |
| Py_DECREF(newargs); |
| Py_DECREF(s_object); |
| return result; |
| } |
| |
| PyDoc_STRVAR(pack_into_doc, |
| "pack_into(fmt, buffer, offset, v1, v2, ...)\n\ |
| \n\ |
| Pack the values v1, v2, ... according to the format string fmt and write\n\ |
| the packed bytes into the writable buffer buf starting at offset. Note\n\ |
| that the offset is a required argument. See help(struct) for more\n\ |
| on format strings."); |
| |
| static PyObject * |
| pack_into(PyObject *self, PyObject *args) |
| { |
| PyObject *s_object, *fmt, *newargs, *result; |
| Py_ssize_t n = PyTuple_GET_SIZE(args); |
| |
| if (n == 0) { |
| PyErr_SetString(PyExc_TypeError, "missing format argument"); |
| return NULL; |
| } |
| fmt = PyTuple_GET_ITEM(args, 0); |
| newargs = PyTuple_GetSlice(args, 1, n); |
| if (newargs == NULL) |
| return NULL; |
| |
| s_object = cache_struct(fmt); |
| if (s_object == NULL) { |
| Py_DECREF(newargs); |
| return NULL; |
| } |
| result = s_pack_into(s_object, newargs); |
| Py_DECREF(newargs); |
| Py_DECREF(s_object); |
| return result; |
| } |
| |
| PyDoc_STRVAR(unpack_doc, |
| "unpack(fmt, buffer) -> (v1, v2, ...)\n\ |
| \n\ |
| Return a tuple containing values unpacked according to the format string\n\ |
| fmt. Requires len(buffer) == calcsize(fmt). See help(struct) for more\n\ |
| on format strings."); |
| |
| static PyObject * |
| unpack(PyObject *self, PyObject *args) |
| { |
| PyObject *s_object, *fmt, *inputstr, *result; |
| |
| if (!PyArg_UnpackTuple(args, "unpack", 2, 2, &fmt, &inputstr)) |
| return NULL; |
| |
| s_object = cache_struct(fmt); |
| if (s_object == NULL) |
| return NULL; |
| result = s_unpack(s_object, inputstr); |
| Py_DECREF(s_object); |
| return result; |
| } |
| |
| PyDoc_STRVAR(unpack_from_doc, |
| "unpack_from(fmt, buffer, offset=0) -> (v1, v2, ...)\n\ |
| \n\ |
| Return a tuple containing values unpacked according to the format string\n\ |
| fmt. Requires len(buffer[offset:]) >= calcsize(fmt). See help(struct)\n\ |
| for more on format strings."); |
| |
| static PyObject * |
| unpack_from(PyObject *self, PyObject *args, PyObject *kwds) |
| { |
| PyObject *s_object, *fmt, *newargs, *result; |
| Py_ssize_t n = PyTuple_GET_SIZE(args); |
| |
| if (n == 0) { |
| PyErr_SetString(PyExc_TypeError, "missing format argument"); |
| return NULL; |
| } |
| fmt = PyTuple_GET_ITEM(args, 0); |
| newargs = PyTuple_GetSlice(args, 1, n); |
| if (newargs == NULL) |
| return NULL; |
| |
| s_object = cache_struct(fmt); |
| if (s_object == NULL) { |
| Py_DECREF(newargs); |
| return NULL; |
| } |
| result = s_unpack_from(s_object, newargs, kwds); |
| Py_DECREF(newargs); |
| Py_DECREF(s_object); |
| return result; |
| } |
| |
| PyDoc_STRVAR(iter_unpack_doc, |
| "iter_unpack(fmt, buffer) -> iterator(v1, v2, ...)\n\ |
| \n\ |
| Return an iterator yielding tuples unpacked from the given bytes\n\ |
| source according to the format string, like a repeated invocation of\n\ |
| unpack_from(). Requires that the bytes length be a multiple of the\n\ |
| format struct size."); |
| |
| static PyObject * |
| iter_unpack(PyObject *self, PyObject *args) |
| { |
| PyObject *s_object, *fmt, *input, *result; |
| |
| if (!PyArg_ParseTuple(args, "OO:iter_unpack", &fmt, &input)) |
| return NULL; |
| |
| s_object = cache_struct(fmt); |
| if (s_object == NULL) |
| return NULL; |
| result = s_iter_unpack(s_object, input); |
| Py_DECREF(s_object); |
| return result; |
| } |
| |
| static struct PyMethodDef module_functions[] = { |
| {"_clearcache", (PyCFunction)clearcache, METH_NOARGS, clearcache_doc}, |
| {"calcsize", calcsize, METH_O, calcsize_doc}, |
| {"iter_unpack", iter_unpack, METH_VARARGS, iter_unpack_doc}, |
| {"pack", pack, METH_VARARGS, pack_doc}, |
| {"pack_into", pack_into, METH_VARARGS, pack_into_doc}, |
| {"unpack", unpack, METH_VARARGS, unpack_doc}, |
| {"unpack_from", (PyCFunction)unpack_from, |
| METH_VARARGS|METH_KEYWORDS, unpack_from_doc}, |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| |
| /* Module initialization */ |
| |
| PyDoc_STRVAR(module_doc, |
| "Functions to convert between Python values and C structs.\n\ |
| Python bytes objects are used to hold the data representing the C struct\n\ |
| and also as format strings (explained below) to describe the layout of data\n\ |
| in the C struct.\n\ |
| \n\ |
| The optional first format char indicates byte order, size and alignment:\n\ |
| @: native order, size & alignment (default)\n\ |
| =: native order, std. size & alignment\n\ |
| <: little-endian, std. size & alignment\n\ |
| >: big-endian, std. size & alignment\n\ |
| !: 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\ |
| ?: _Bool (requires C99; if not available, char is used instead)\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 (with count byte).\n\ |
| Special cases (only available in native format):\n\ |
| n:ssize_t; N:size_t;\n\ |
| P:an integer type that is wide enough to hold a pointer.\n\ |
| Special case (not in native mode unless 'long long' in platform C):\n\ |
| q:long long; Q:unsigned long long\n\ |
| Whitespace between formats is ignored.\n\ |
| \n\ |
| The variable struct.error is an exception raised on errors.\n"); |
| |
| |
| static struct PyModuleDef _structmodule = { |
| PyModuleDef_HEAD_INIT, |
| "_struct", |
| module_doc, |
| -1, |
| module_functions, |
| NULL, |
| NULL, |
| NULL, |
| NULL |
| }; |
| |
| PyMODINIT_FUNC |
| PyInit__struct(void) |
| { |
| PyObject *m; |
| |
| m = PyModule_Create(&_structmodule); |
| if (m == NULL) |
| return NULL; |
| |
| Py_TYPE(&PyStructType) = &PyType_Type; |
| if (PyType_Ready(&PyStructType) < 0) |
| return NULL; |
| |
| /* Check endian and swap in faster functions */ |
| { |
| const formatdef *native = native_table; |
| formatdef *other, *ptr; |
| #if PY_LITTLE_ENDIAN |
| other = lilendian_table; |
| #else |
| other = bigendian_table; |
| #endif |
| /* Scan through the native table, find a matching |
| entry in the endian table and swap in the |
| native implementations whenever possible |
| (64-bit platforms may not have "standard" sizes) */ |
| while (native->format != '\0' && other->format != '\0') { |
| ptr = other; |
| while (ptr->format != '\0') { |
| if (ptr->format == native->format) { |
| /* Match faster when formats are |
| listed in the same order */ |
| if (ptr == other) |
| other++; |
| /* Only use the trick if the |
| size matches */ |
| if (ptr->size != native->size) |
| break; |
| /* Skip float and double, could be |
| "unknown" float format */ |
| if (ptr->format == 'd' || ptr->format == 'f') |
| break; |
| ptr->pack = native->pack; |
| ptr->unpack = native->unpack; |
| break; |
| } |
| ptr++; |
| } |
| native++; |
| } |
| } |
| |
| /* Add some symbolic constants to the module */ |
| if (StructError == NULL) { |
| StructError = PyErr_NewException("struct.error", NULL, NULL); |
| if (StructError == NULL) |
| return NULL; |
| } |
| |
| Py_INCREF(StructError); |
| PyModule_AddObject(m, "error", StructError); |
| |
| Py_INCREF((PyObject*)&PyStructType); |
| PyModule_AddObject(m, "Struct", (PyObject*)&PyStructType); |
| |
| return m; |
| } |