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      1 #ifndef Py_PYMACRO_H
      2 #define Py_PYMACRO_H
      3 
      4 /* Minimum value between x and y */
      5 #define Py_MIN(x, y) (((x) > (y)) ? (y) : (x))
      6 
      7 /* Maximum value between x and y */
      8 #define Py_MAX(x, y) (((x) > (y)) ? (x) : (y))
      9 
     10 /* Absolute value of the number x */
     11 #define Py_ABS(x) ((x) < 0 ? -(x) : (x))
     12 
     13 #define _Py_XSTRINGIFY(x) #x
     14 
     15 /* Convert the argument to a string. For example, Py_STRINGIFY(123) is replaced
     16    with "123" by the preprocessor. Defines are also replaced by their value.
     17    For example Py_STRINGIFY(__LINE__) is replaced by the line number, not
     18    by "__LINE__". */
     19 #define Py_STRINGIFY(x) _Py_XSTRINGIFY(x)
     20 
     21 /* Get the size of a structure member in bytes */
     22 #define Py_MEMBER_SIZE(type, member) sizeof(((type *)0)->member)
     23 
     24 /* Argument must be a char or an int in [-128, 127] or [0, 255]. */
     25 #define Py_CHARMASK(c) ((unsigned char)((c) & 0xff))
     26 
     27 /* Assert a build-time dependency, as an expression.
     28 
     29    Your compile will fail if the condition isn't true, or can't be evaluated
     30    by the compiler. This can be used in an expression: its value is 0.
     31 
     32    Example:
     33 
     34    #define foo_to_char(foo)  \
     35        ((char *)(foo)        \
     36         + Py_BUILD_ASSERT_EXPR(offsetof(struct foo, string) == 0))
     37 
     38    Written by Rusty Russell, public domain, http://ccodearchive.net/ */
     39 #define Py_BUILD_ASSERT_EXPR(cond) \
     40     (sizeof(char [1 - 2*!(cond)]) - 1)
     41 
     42 #define Py_BUILD_ASSERT(cond)  do {         \
     43         (void)Py_BUILD_ASSERT_EXPR(cond);   \
     44     } while(0)
     45 
     46 /* Get the number of elements in a visible array
     47 
     48    This does not work on pointers, or arrays declared as [], or function
     49    parameters. With correct compiler support, such usage will cause a build
     50    error (see Py_BUILD_ASSERT_EXPR).
     51 
     52    Written by Rusty Russell, public domain, http://ccodearchive.net/
     53 
     54    Requires at GCC 3.1+ */
     55 #if (defined(__GNUC__) && !defined(__STRICT_ANSI__) && \
     56     (((__GNUC__ == 3) && (__GNU_MINOR__ >= 1)) || (__GNUC__ >= 4)))
     57 /* Two gcc extensions.
     58    &a[0] degrades to a pointer: a different type from an array */
     59 #define Py_ARRAY_LENGTH(array) \
     60     (sizeof(array) / sizeof((array)[0]) \
     61      + Py_BUILD_ASSERT_EXPR(!__builtin_types_compatible_p(typeof(array), \
     62                                                           typeof(&(array)[0]))))
     63 #else
     64 #define Py_ARRAY_LENGTH(array) \
     65     (sizeof(array) / sizeof((array)[0]))
     66 #endif
     67 
     68 
     69 /* Define macros for inline documentation. */
     70 #define PyDoc_VAR(name) static char name[]
     71 #define PyDoc_STRVAR(name,str) PyDoc_VAR(name) = PyDoc_STR(str)
     72 #ifdef WITH_DOC_STRINGS
     73 #define PyDoc_STR(str) str
     74 #else
     75 #define PyDoc_STR(str) ""
     76 #endif
     77 
     78 /* Below "a" is a power of 2. */
     79 /* Round down size "n" to be a multiple of "a". */
     80 #define _Py_SIZE_ROUND_DOWN(n, a) ((size_t)(n) & ~(size_t)((a) - 1))
     81 /* Round up size "n" to be a multiple of "a". */
     82 #define _Py_SIZE_ROUND_UP(n, a) (((size_t)(n) + \
     83         (size_t)((a) - 1)) & ~(size_t)((a) - 1))
     84 /* Round pointer "p" down to the closest "a"-aligned address <= "p". */
     85 #define _Py_ALIGN_DOWN(p, a) ((void *)((uintptr_t)(p) & ~(uintptr_t)((a) - 1)))
     86 /* Round pointer "p" up to the closest "a"-aligned address >= "p". */
     87 #define _Py_ALIGN_UP(p, a) ((void *)(((uintptr_t)(p) + \
     88         (uintptr_t)((a) - 1)) & ~(uintptr_t)((a) - 1)))
     89 /* Check if pointer "p" is aligned to "a"-bytes boundary. */
     90 #define _Py_IS_ALIGNED(p, a) (!((uintptr_t)(p) & (uintptr_t)((a) - 1)))
     91 
     92 #ifdef __GNUC__
     93 #define Py_UNUSED(name) _unused_ ## name __attribute__((unused))
     94 #else
     95 #define Py_UNUSED(name) _unused_ ## name
     96 #endif
     97 
     98 #endif /* Py_PYMACRO_H */
     99