1  #ifndef Py_CPYTHON_BYTESOBJECT_H
       2  #  error "this header file must not be included directly"
       3  #endif
       4  
       5  typedef struct {
       6      PyObject_VAR_HEAD
       7      Py_DEPRECATED(3.11) Py_hash_t ob_shash;
       8      char ob_sval[1];
       9  
      10      /* Invariants:
      11       *     ob_sval contains space for 'ob_size+1' elements.
      12       *     ob_sval[ob_size] == 0.
      13       *     ob_shash is the hash of the byte string or -1 if not computed yet.
      14       */
      15  } PyBytesObject;
      16  
      17  PyAPI_FUNC(int) _PyBytes_Resize(PyObject **, Py_ssize_t);
      18  PyAPI_FUNC(PyObject*) _PyBytes_FormatEx(
      19      const char *format,
      20      Py_ssize_t format_len,
      21      PyObject *args,
      22      int use_bytearray);
      23  PyAPI_FUNC(PyObject*) _PyBytes_FromHex(
      24      PyObject *string,
      25      int use_bytearray);
      26  
      27  /* Helper for PyBytes_DecodeEscape that detects invalid escape chars. */
      28  PyAPI_FUNC(PyObject *) _PyBytes_DecodeEscape(const char *, Py_ssize_t,
      29                                               const char *, const char **);
      30  
      31  /* Macros and static inline functions, trading safety for speed */
      32  #define _PyBytes_CAST(op) \
      33      (assert(PyBytes_Check(op)), _Py_CAST(PyBytesObject*, op))
      34  
      35  static inline char* PyBytes_AS_STRING(PyObject *op)
      36  {
      37      return _PyBytes_CAST(op)->ob_sval;
      38  }
      39  #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
      40  #  define PyBytes_AS_STRING(op) PyBytes_AS_STRING(_PyObject_CAST(op))
      41  #endif
      42  
      43  static inline Py_ssize_t PyBytes_GET_SIZE(PyObject *op) {
      44      PyBytesObject *self = _PyBytes_CAST(op);
      45      return Py_SIZE(self);
      46  }
      47  #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
      48  #  define PyBytes_GET_SIZE(self) PyBytes_GET_SIZE(_PyObject_CAST(self))
      49  #endif
      50  
      51  /* _PyBytes_Join(sep, x) is like sep.join(x).  sep must be PyBytesObject*,
      52     x must be an iterable object. */
      53  PyAPI_FUNC(PyObject *) _PyBytes_Join(PyObject *sep, PyObject *x);
      54  
      55  
      56  /* The _PyBytesWriter structure is big: it contains an embedded "stack buffer".
      57     A _PyBytesWriter variable must be declared at the end of variables in a
      58     function to optimize the memory allocation on the stack. */
      59  typedef struct {
      60      /* bytes, bytearray or NULL (when the small buffer is used) */
      61      PyObject *buffer;
      62  
      63      /* Number of allocated size. */
      64      Py_ssize_t allocated;
      65  
      66      /* Minimum number of allocated bytes,
      67         incremented by _PyBytesWriter_Prepare() */
      68      Py_ssize_t min_size;
      69  
      70      /* If non-zero, use a bytearray instead of a bytes object for buffer. */
      71      int use_bytearray;
      72  
      73      /* If non-zero, overallocate the buffer (default: 0).
      74         This flag must be zero if use_bytearray is non-zero. */
      75      int overallocate;
      76  
      77      /* Stack buffer */
      78      int use_small_buffer;
      79      char small_buffer[512];
      80  } _PyBytesWriter;
      81  
      82  /* Initialize a bytes writer
      83  
      84     By default, the overallocation is disabled. Set the overallocate attribute
      85     to control the allocation of the buffer. */
      86  PyAPI_FUNC(void) _PyBytesWriter_Init(_PyBytesWriter *writer);
      87  
      88  /* Get the buffer content and reset the writer.
      89     Return a bytes object, or a bytearray object if use_bytearray is non-zero.
      90     Raise an exception and return NULL on error. */
      91  PyAPI_FUNC(PyObject *) _PyBytesWriter_Finish(_PyBytesWriter *writer,
      92      void *str);
      93  
      94  /* Deallocate memory of a writer (clear its internal buffer). */
      95  PyAPI_FUNC(void) _PyBytesWriter_Dealloc(_PyBytesWriter *writer);
      96  
      97  /* Allocate the buffer to write size bytes.
      98     Return the pointer to the beginning of buffer data.
      99     Raise an exception and return NULL on error. */
     100  PyAPI_FUNC(void*) _PyBytesWriter_Alloc(_PyBytesWriter *writer,
     101      Py_ssize_t size);
     102  
     103  /* Ensure that the buffer is large enough to write *size* bytes.
     104     Add size to the writer minimum size (min_size attribute).
     105  
     106     str is the current pointer inside the buffer.
     107     Return the updated current pointer inside the buffer.
     108     Raise an exception and return NULL on error. */
     109  PyAPI_FUNC(void*) _PyBytesWriter_Prepare(_PyBytesWriter *writer,
     110      void *str,
     111      Py_ssize_t size);
     112  
     113  /* Resize the buffer to make it larger.
     114     The new buffer may be larger than size bytes because of overallocation.
     115     Return the updated current pointer inside the buffer.
     116     Raise an exception and return NULL on error.
     117  
     118     Note: size must be greater than the number of allocated bytes in the writer.
     119  
     120     This function doesn't use the writer minimum size (min_size attribute).
     121  
     122     See also _PyBytesWriter_Prepare().
     123     */
     124  PyAPI_FUNC(void*) _PyBytesWriter_Resize(_PyBytesWriter *writer,
     125      void *str,
     126      Py_ssize_t size);
     127  
     128  /* Write bytes.
     129     Raise an exception and return NULL on error. */
     130  PyAPI_FUNC(void*) _PyBytesWriter_WriteBytes(_PyBytesWriter *writer,
     131      void *str,
     132      const void *bytes,
     133      Py_ssize_t size);