1#ifndef Py_CPYTHON_BYTESOBJECT_H
2#  error "this header file must not be included directly"
3#endif
4
5typedef 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
17PyAPI_FUNC(int) _PyBytes_Resize(PyObject **, Py_ssize_t);
18PyAPI_FUNC(PyObject*) _PyBytes_FormatEx(
19    const char *format,
20    Py_ssize_t format_len,
21    PyObject *args,
22    int use_bytearray);
23PyAPI_FUNC(PyObject*) _PyBytes_FromHex(
24    PyObject *string,
25    int use_bytearray);
26
27/* Helper for PyBytes_DecodeEscape that detects invalid escape chars. */
28PyAPI_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
35static 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
43static 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. */
53PyAPI_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. */
59typedef 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. */
86PyAPI_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. */
91PyAPI_FUNC(PyObject *) _PyBytesWriter_Finish(_PyBytesWriter *writer,
92    void *str);
93
94/* Deallocate memory of a writer (clear its internal buffer). */
95PyAPI_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. */
100PyAPI_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. */
109PyAPI_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   */
124PyAPI_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. */
130PyAPI_FUNC(void*) _PyBytesWriter_WriteBytes(_PyBytesWriter *writer,
131    void *str,
132    const void *bytes,
133    Py_ssize_t size);
134