add ydb deps

1 files changed, 833 insertions, 0 deletions

diff --git a/contrib/tools/python3/src/Objects/bytes_methods.c b/contrib/tools/python3/src/Objects/bytes_methods.c
new file mode 100644
index 0000000000..994fb8a73c
--- /dev/null
+++ b/contrib/tools/python3/src/Objects/bytes_methods.c
@@ -0,0 +1,833 @@
+#define PY_SSIZE_T_CLEAN
+#include "Python.h"
+#include "pycore_abstract.h"   // _PyIndex_Check()
+#include "pycore_bytes_methods.h"
+
+PyDoc_STRVAR_shared(_Py_isspace__doc__,
+"B.isspace() -> bool\n\
+\n\
+Return True if all characters in B are whitespace\n\
+and there is at least one character in B, False otherwise.");
+
+PyObject*
+_Py_bytes_isspace(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+
+    /* Shortcut for single character strings */
+    if (len == 1 && Py_ISSPACE(*p))
+        Py_RETURN_TRUE;
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    for (; p < e; p++) {
+        if (!Py_ISSPACE(*p))
+            Py_RETURN_FALSE;
+    }
+    Py_RETURN_TRUE;
+}
+
+
+PyDoc_STRVAR_shared(_Py_isalpha__doc__,
+"B.isalpha() -> bool\n\
+\n\
+Return True if all characters in B are alphabetic\n\
+and there is at least one character in B, False otherwise.");
+
+PyObject*
+_Py_bytes_isalpha(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+
+    /* Shortcut for single character strings */
+    if (len == 1 && Py_ISALPHA(*p))
+        Py_RETURN_TRUE;
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    for (; p < e; p++) {
+        if (!Py_ISALPHA(*p))
+            Py_RETURN_FALSE;
+    }
+    Py_RETURN_TRUE;
+}
+
+
+PyDoc_STRVAR_shared(_Py_isalnum__doc__,
+"B.isalnum() -> bool\n\
+\n\
+Return True if all characters in B are alphanumeric\n\
+and there is at least one character in B, False otherwise.");
+
+PyObject*
+_Py_bytes_isalnum(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+
+    /* Shortcut for single character strings */
+    if (len == 1 && Py_ISALNUM(*p))
+        Py_RETURN_TRUE;
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    for (; p < e; p++) {
+        if (!Py_ISALNUM(*p))
+            Py_RETURN_FALSE;
+    }
+    Py_RETURN_TRUE;
+}
+
+
+PyDoc_STRVAR_shared(_Py_isascii__doc__,
+"B.isascii() -> bool\n\
+\n\
+Return True if B is empty or all characters in B are ASCII,\n\
+False otherwise.");
+
+// Optimization is copied from ascii_decode in unicodeobject.c
+/* Mask to quickly check whether a C 'size_t' contains a
+   non-ASCII, UTF8-encoded char. */
+#if (SIZEOF_SIZE_T == 8)
+# define ASCII_CHAR_MASK 0x8080808080808080ULL
+#elif (SIZEOF_SIZE_T == 4)
+# define ASCII_CHAR_MASK 0x80808080U
+#else
+# error C 'size_t' size should be either 4 or 8!
+#endif
+
+PyObject*
+_Py_bytes_isascii(const char *cptr, Py_ssize_t len)
+{
+    const char *p = cptr;
+    const char *end = p + len;
+
+    while (p < end) {
+        /* Fast path, see in STRINGLIB(utf8_decode) in stringlib/codecs.h
+           for an explanation. */
+        if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {
+            /* Help allocation */
+            const char *_p = p;
+            while (_p + SIZEOF_SIZE_T <= end) {
+                size_t value = *(const size_t *) _p;
+                if (value & ASCII_CHAR_MASK) {
+                    Py_RETURN_FALSE;
+                }
+                _p += SIZEOF_SIZE_T;
+            }
+            p = _p;
+            if (_p == end)
+                break;
+        }
+        if ((unsigned char)*p & 0x80) {
+            Py_RETURN_FALSE;
+        }
+        p++;
+    }
+    Py_RETURN_TRUE;
+}
+
+#undef ASCII_CHAR_MASK
+
+
+PyDoc_STRVAR_shared(_Py_isdigit__doc__,
+"B.isdigit() -> bool\n\
+\n\
+Return True if all characters in B are digits\n\
+and there is at least one character in B, False otherwise.");
+
+PyObject*
+_Py_bytes_isdigit(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+
+    /* Shortcut for single character strings */
+    if (len == 1 && Py_ISDIGIT(*p))
+        Py_RETURN_TRUE;
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    for (; p < e; p++) {
+        if (!Py_ISDIGIT(*p))
+            Py_RETURN_FALSE;
+    }
+    Py_RETURN_TRUE;
+}
+
+
+PyDoc_STRVAR_shared(_Py_islower__doc__,
+"B.islower() -> bool\n\
+\n\
+Return True if all cased characters in B are lowercase and there is\n\
+at least one cased character in B, False otherwise.");
+
+PyObject*
+_Py_bytes_islower(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+    int cased;
+
+    /* Shortcut for single character strings */
+    if (len == 1)
+        return PyBool_FromLong(Py_ISLOWER(*p));
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    cased = 0;
+    for (; p < e; p++) {
+        if (Py_ISUPPER(*p))
+            Py_RETURN_FALSE;
+        else if (!cased && Py_ISLOWER(*p))
+            cased = 1;
+    }
+    return PyBool_FromLong(cased);
+}
+
+
+PyDoc_STRVAR_shared(_Py_isupper__doc__,
+"B.isupper() -> bool\n\
+\n\
+Return True if all cased characters in B are uppercase and there is\n\
+at least one cased character in B, False otherwise.");
+
+PyObject*
+_Py_bytes_isupper(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+    int cased;
+
+    /* Shortcut for single character strings */
+    if (len == 1)
+        return PyBool_FromLong(Py_ISUPPER(*p));
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    cased = 0;
+    for (; p < e; p++) {
+        if (Py_ISLOWER(*p))
+            Py_RETURN_FALSE;
+        else if (!cased && Py_ISUPPER(*p))
+            cased = 1;
+    }
+    return PyBool_FromLong(cased);
+}
+
+
+PyDoc_STRVAR_shared(_Py_istitle__doc__,
+"B.istitle() -> bool\n\
+\n\
+Return True if B is a titlecased string and there is at least one\n\
+character in B, i.e. uppercase characters may only follow uncased\n\
+characters and lowercase characters only cased ones. Return False\n\
+otherwise.");
+
+PyObject*
+_Py_bytes_istitle(const char *cptr, Py_ssize_t len)
+{
+    const unsigned char *p
+        = (const unsigned char *) cptr;
+    const unsigned char *e;
+    int cased, previous_is_cased;
+
+    /* Shortcut for single character strings */
+    if (len == 1)
+        return PyBool_FromLong(Py_ISUPPER(*p));
+
+    /* Special case for empty strings */
+    if (len == 0)
+        Py_RETURN_FALSE;
+
+    e = p + len;
+    cased = 0;
+    previous_is_cased = 0;
+    for (; p < e; p++) {
+        const unsigned char ch = *p;
+
+        if (Py_ISUPPER(ch)) {
+            if (previous_is_cased)
+                Py_RETURN_FALSE;
+            previous_is_cased = 1;
+            cased = 1;
+        }
+        else if (Py_ISLOWER(ch)) {
+            if (!previous_is_cased)
+                Py_RETURN_FALSE;
+            previous_is_cased = 1;
+            cased = 1;
+        }
+        else
+            previous_is_cased = 0;
+    }
+    return PyBool_FromLong(cased);
+}
+
+
+PyDoc_STRVAR_shared(_Py_lower__doc__,
+"B.lower() -> copy of B\n\
+\n\
+Return a copy of B with all ASCII characters converted to lowercase.");
+
+void
+_Py_bytes_lower(char *result, const char *cptr, Py_ssize_t len)
+{
+    Py_ssize_t i;
+
+    for (i = 0; i < len; i++) {
+        result[i] = Py_TOLOWER((unsigned char) cptr[i]);
+    }
+}
+
+
+PyDoc_STRVAR_shared(_Py_upper__doc__,
+"B.upper() -> copy of B\n\
+\n\
+Return a copy of B with all ASCII characters converted to uppercase.");
+
+void
+_Py_bytes_upper(char *result, const char *cptr, Py_ssize_t len)
+{
+    Py_ssize_t i;
+
+    for (i = 0; i < len; i++) {
+        result[i] = Py_TOUPPER((unsigned char) cptr[i]);
+    }
+}
+
+
+PyDoc_STRVAR_shared(_Py_title__doc__,
+"B.title() -> copy of B\n\
+\n\
+Return a titlecased version of B, i.e. ASCII words start with uppercase\n\
+characters, all remaining cased characters have lowercase.");
+
+void
+_Py_bytes_title(char *result, const char *s, Py_ssize_t len)
+{
+    Py_ssize_t i;
+    int previous_is_cased = 0;
+
+    for (i = 0; i < len; i++) {
+        int c = Py_CHARMASK(*s++);
+        if (Py_ISLOWER(c)) {
+            if (!previous_is_cased)
+                c = Py_TOUPPER(c);
+            previous_is_cased = 1;
+        } else if (Py_ISUPPER(c)) {
+            if (previous_is_cased)
+                c = Py_TOLOWER(c);
+            previous_is_cased = 1;
+        } else
+            previous_is_cased = 0;
+        *result++ = c;
+    }
+}
+
+
+PyDoc_STRVAR_shared(_Py_capitalize__doc__,
+"B.capitalize() -> copy of B\n\
+\n\
+Return a copy of B with only its first character capitalized (ASCII)\n\
+and the rest lower-cased.");
+
+void
+_Py_bytes_capitalize(char *result, const char *s, Py_ssize_t len)
+{
+    if (len > 0) {
+        *result = Py_TOUPPER(*s);
+        _Py_bytes_lower(result + 1, s + 1, len - 1);
+    }
+}
+
+
+PyDoc_STRVAR_shared(_Py_swapcase__doc__,
+"B.swapcase() -> copy of B\n\
+\n\
+Return a copy of B with uppercase ASCII characters converted\n\
+to lowercase ASCII and vice versa.");
+
+void
+_Py_bytes_swapcase(char *result, const char *s, Py_ssize_t len)
+{
+    Py_ssize_t i;
+
+    for (i = 0; i < len; i++) {
+        int c = Py_CHARMASK(*s++);
+        if (Py_ISLOWER(c)) {
+            *result = Py_TOUPPER(c);
+        }
+        else if (Py_ISUPPER(c)) {
+            *result = Py_TOLOWER(c);
+        }
+        else
+            *result = c;
+        result++;
+    }
+}
+
+
+PyDoc_STRVAR_shared(_Py_maketrans__doc__,
+"B.maketrans(frm, to) -> translation table\n\
+\n\
+Return a translation table (a bytes object of length 256) suitable\n\
+for use in the bytes or bytearray translate method where each byte\n\
+in frm is mapped to the byte at the same position in to.\n\
+The bytes objects frm and to must be of the same length.");
+
+PyObject *
+_Py_bytes_maketrans(Py_buffer *frm, Py_buffer *to)
+{
+    PyObject *res = NULL;
+    Py_ssize_t i;
+    char *p;
+
+    if (frm->len != to->len) {
+        PyErr_Format(PyExc_ValueError,
+                     "maketrans arguments must have same length");
+        return NULL;
+    }
+    res = PyBytes_FromStringAndSize(NULL, 256);
+    if (!res)
+        return NULL;
+    p = PyBytes_AS_STRING(res);
+    for (i = 0; i < 256; i++)
+        p[i] = (char) i;
+    for (i = 0; i < frm->len; i++) {
+        p[((unsigned char *)frm->buf)[i]] = ((char *)to->buf)[i];
+    }
+
+    return res;
+}
+
+#define FASTSEARCH fastsearch
+#define STRINGLIB(F) stringlib_##F
+#define STRINGLIB_CHAR char
+#define STRINGLIB_SIZEOF_CHAR 1
+
+#include "stringlib/fastsearch.h"
+#include "stringlib/count.h"
+#include "stringlib/find.h"
+
+/*
+Wraps stringlib_parse_args_finds() and additionally checks the first
+argument type.
+
+In case the first argument is a bytes-like object, sets it to subobj,
+and doesn't touch the byte parameter.
+In case it is an integer in range(0, 256), writes the integer value
+to byte, and sets subobj to NULL.
+
+The other parameters are similar to those of
+stringlib_parse_args_finds().
+*/
+
+Py_LOCAL_INLINE(int)
+parse_args_finds_byte(const char *function_name, PyObject *args,
+                      PyObject **subobj, char *byte,
+                      Py_ssize_t *start, Py_ssize_t *end)
+{
+    PyObject *tmp_subobj;
+    Py_ssize_t ival;
+
+    if(!stringlib_parse_args_finds(function_name, args, &tmp_subobj,
+                                   start, end))
+        return 0;
+
+    if (PyObject_CheckBuffer(tmp_subobj)) {
+        *subobj = tmp_subobj;
+        return 1;
+    }
+
+    if (!_PyIndex_Check(tmp_subobj)) {
+        PyErr_Format(PyExc_TypeError,
+                     "argument should be integer or bytes-like object, "
+                     "not '%.200s'",
+                     Py_TYPE(tmp_subobj)->tp_name);
+        return 0;
+    }
+
+    ival = PyNumber_AsSsize_t(tmp_subobj, NULL);
+    if (ival == -1 && PyErr_Occurred()) {
+        return 0;
+    }
+    if (ival < 0 || ival > 255) {
+        PyErr_SetString(PyExc_ValueError, "byte must be in range(0, 256)");
+        return 0;
+    }
+
+    *subobj = NULL;
+    *byte = (char)ival;
+    return 1;
+}
+
+/* helper macro to fixup start/end slice values */
+#define ADJUST_INDICES(start, end, len)         \
+    if (end > len)                          \
+        end = len;                          \
+    else if (end < 0) {                     \
+        end += len;                         \
+        if (end < 0)                        \
+        end = 0;                        \
+    }                                       \
+    if (start < 0) {                        \
+        start += len;                       \
+        if (start < 0)                      \
+        start = 0;                      \
+    }
+
+Py_LOCAL_INLINE(Py_ssize_t)
+find_internal(const char *str, Py_ssize_t len,
+              const char *function_name, PyObject *args, int dir)
+{
+    PyObject *subobj;
+    char byte;
+    Py_buffer subbuf;
+    const char *sub;
+    Py_ssize_t sub_len;
+    Py_ssize_t start = 0, end = PY_SSIZE_T_MAX;
+    Py_ssize_t res;
+
+    if (!parse_args_finds_byte(function_name, args,
+                               &subobj, &byte, &start, &end))
+        return -2;
+
+    if (subobj) {
+        if (PyObject_GetBuffer(subobj, &subbuf, PyBUF_SIMPLE) != 0)
+            return -2;
+
+        sub = subbuf.buf;
+        sub_len = subbuf.len;
+    }
+    else {
+        sub = &byte;
+        sub_len = 1;
+    }
+
+    ADJUST_INDICES(start, end, len);
+    if (end - start < sub_len)
+        res = -1;
+    else if (sub_len == 1) {
+        if (dir > 0)
+            res = stringlib_find_char(
+                str + start, end - start,
+                *sub);
+        else
+            res = stringlib_rfind_char(
+                str + start, end - start,
+                *sub);
+        if (res >= 0)
+            res += start;
+    }
+    else {
+        if (dir > 0)
+            res = stringlib_find_slice(
+                str, len,
+                sub, sub_len, start, end);
+        else
+            res = stringlib_rfind_slice(
+                str, len,
+                sub, sub_len, start, end);
+    }
+
+    if (subobj)
+        PyBuffer_Release(&subbuf);
+
+    return res;
+}
+
+PyDoc_STRVAR_shared(_Py_find__doc__,
+"B.find(sub[, start[, end]]) -> int\n\
+\n\
+Return the lowest index in B where subsection sub is found,\n\
+such that sub is contained within B[start,end].  Optional\n\
+arguments start and end are interpreted as in slice notation.\n\
+\n\
+Return -1 on failure.");
+
+PyObject *
+_Py_bytes_find(const char *str, Py_ssize_t len, PyObject *args)
+{
+    Py_ssize_t result = find_internal(str, len, "find", args, +1);
+    if (result == -2)
+        return NULL;
+    return PyLong_FromSsize_t(result);
+}
+
+PyDoc_STRVAR_shared(_Py_index__doc__,
+"B.index(sub[, start[, end]]) -> int\n\
+\n\
+Return the lowest index in B where subsection sub is found,\n\
+such that sub is contained within B[start,end].  Optional\n\
+arguments start and end are interpreted as in slice notation.\n\
+\n\
+Raises ValueError when the subsection is not found.");
+
+PyObject *
+_Py_bytes_index(const char *str, Py_ssize_t len, PyObject *args)
+{
+    Py_ssize_t result = find_internal(str, len, "index", args, +1);
+    if (result == -2)
+        return NULL;
+    if (result == -1) {
+        PyErr_SetString(PyExc_ValueError,
+                        "subsection not found");
+        return NULL;
+    }
+    return PyLong_FromSsize_t(result);
+}
+
+PyDoc_STRVAR_shared(_Py_rfind__doc__,
+"B.rfind(sub[, start[, end]]) -> int\n\
+\n\
+Return the highest index in B where subsection sub is found,\n\
+such that sub is contained within B[start,end].  Optional\n\
+arguments start and end are interpreted as in slice notation.\n\
+\n\
+Return -1 on failure.");
+
+PyObject *
+_Py_bytes_rfind(const char *str, Py_ssize_t len, PyObject *args)
+{
+    Py_ssize_t result = find_internal(str, len, "rfind", args, -1);
+    if (result == -2)
+        return NULL;
+    return PyLong_FromSsize_t(result);
+}
+
+PyDoc_STRVAR_shared(_Py_rindex__doc__,
+"B.rindex(sub[, start[, end]]) -> int\n\
+\n\
+Return the highest index in B where subsection sub is found,\n\
+such that sub is contained within B[start,end].  Optional\n\
+arguments start and end are interpreted as in slice notation.\n\
+\n\
+Raise ValueError when the subsection is not found.");
+
+PyObject *
+_Py_bytes_rindex(const char *str, Py_ssize_t len, PyObject *args)
+{
+    Py_ssize_t result = find_internal(str, len, "rindex", args, -1);
+    if (result == -2)
+        return NULL;
+    if (result == -1) {
+        PyErr_SetString(PyExc_ValueError,
+                        "subsection not found");
+        return NULL;
+    }
+    return PyLong_FromSsize_t(result);
+}
+
+PyDoc_STRVAR_shared(_Py_count__doc__,
+"B.count(sub[, start[, end]]) -> int\n\
+\n\
+Return the number of non-overlapping occurrences of subsection sub in\n\
+bytes B[start:end].  Optional arguments start and end are interpreted\n\
+as in slice notation.");
+
+PyObject *
+_Py_bytes_count(const char *str, Py_ssize_t len, PyObject *args)
+{
+    PyObject *sub_obj;
+    const char *sub;
+    Py_ssize_t sub_len;
+    char byte;
+    Py_ssize_t start = 0, end = PY_SSIZE_T_MAX;
+
+    Py_buffer vsub;
+    PyObject *count_obj;
+
+    if (!parse_args_finds_byte("count", args,
+                               &sub_obj, &byte, &start, &end))
+        return NULL;
+
+    if (sub_obj) {
+        if (PyObject_GetBuffer(sub_obj, &vsub, PyBUF_SIMPLE) != 0)
+            return NULL;
+
+        sub = vsub.buf;
+        sub_len = vsub.len;
+    }
+    else {
+        sub = &byte;
+        sub_len = 1;
+    }
+
+    ADJUST_INDICES(start, end, len);
+
+    count_obj = PyLong_FromSsize_t(
+        stringlib_count(str + start, end - start, sub, sub_len, PY_SSIZE_T_MAX)
+        );
+
+    if (sub_obj)
+        PyBuffer_Release(&vsub);
+
+    return count_obj;
+}
+
+int
+_Py_bytes_contains(const char *str, Py_ssize_t len, PyObject *arg)
+{
+    Py_ssize_t ival = PyNumber_AsSsize_t(arg, NULL);
+    if (ival == -1 && PyErr_Occurred()) {
+        Py_buffer varg;
+        Py_ssize_t pos;
+        PyErr_Clear();
+        if (PyObject_GetBuffer(arg, &varg, PyBUF_SIMPLE) != 0)
+            return -1;
+        pos = stringlib_find(str, len,
+                             varg.buf, varg.len, 0);
+        PyBuffer_Release(&varg);
+        return pos >= 0;
+    }
+    if (ival < 0 || ival >= 256) {
+        PyErr_SetString(PyExc_ValueError, "byte must be in range(0, 256)");
+        return -1;
+    }
+
+    return memchr(str, (int) ival, len) != NULL;
+}
+
+
+/* Matches the end (direction >= 0) or start (direction < 0) of the buffer
+ * against substr, using the start and end arguments. Returns
+ * -1 on error, 0 if not found and 1 if found.
+ */
+static int
+tailmatch(const char *str, Py_ssize_t len, PyObject *substr,
+          Py_ssize_t start, Py_ssize_t end, int direction)
+{
+    Py_buffer sub_view = {NULL, NULL};
+    const char *sub;
+    Py_ssize_t slen;
+
+    if (PyBytes_Check(substr)) {
+        sub = PyBytes_AS_STRING(substr);
+        slen = PyBytes_GET_SIZE(substr);
+    }
+    else {
+        if (PyObject_GetBuffer(substr, &sub_view, PyBUF_SIMPLE) != 0)
+            return -1;
+        sub = sub_view.buf;
+        slen = sub_view.len;
+    }
+
+    ADJUST_INDICES(start, end, len);
+
+    if (direction < 0) {
+        /* startswith */
+        if (start > len - slen)
+            goto notfound;
+    } else {
+        /* endswith */
+        if (end - start < slen || start > len)
+            goto notfound;
+
+        if (end - slen > start)
+            start = end - slen;
+    }
+    if (end - start < slen)
+        goto notfound;
+    if (memcmp(str + start, sub, slen) != 0)
+        goto notfound;
+
+    PyBuffer_Release(&sub_view);
+    return 1;
+
+notfound:
+    PyBuffer_Release(&sub_view);
+    return 0;
+}
+
+static PyObject *
+_Py_bytes_tailmatch(const char *str, Py_ssize_t len,
+                    const char *function_name, PyObject *args,
+                    int direction)
+{
+    Py_ssize_t start = 0;
+    Py_ssize_t end = PY_SSIZE_T_MAX;
+    PyObject *subobj;
+    int result;
+
+    if (!stringlib_parse_args_finds(function_name, args, &subobj, &start, &end))
+        return NULL;
+    if (PyTuple_Check(subobj)) {
+        Py_ssize_t i;
+        for (i = 0; i < PyTuple_GET_SIZE(subobj); i++) {
+            result = tailmatch(str, len, PyTuple_GET_ITEM(subobj, i),
+                               start, end, direction);
+            if (result == -1)
+                return NULL;
+            else if (result) {
+                Py_RETURN_TRUE;
+            }
+        }
+        Py_RETURN_FALSE;
+    }
+    result = tailmatch(str, len, subobj, start, end, direction);
+    if (result == -1) {
+        if (PyErr_ExceptionMatches(PyExc_TypeError))
+            PyErr_Format(PyExc_TypeError,
+                         "%s first arg must be bytes or a tuple of bytes, "
+                         "not %s",
+                         function_name, Py_TYPE(subobj)->tp_name);
+        return NULL;
+    }
+    else
+        return PyBool_FromLong(result);
+}
+
+PyDoc_STRVAR_shared(_Py_startswith__doc__,
+"B.startswith(prefix[, start[, end]]) -> bool\n\
+\n\
+Return True if B starts with the specified prefix, False otherwise.\n\
+With optional start, test B beginning at that position.\n\
+With optional end, stop comparing B at that position.\n\
+prefix can also be a tuple of bytes to try.");
+
+PyObject *
+_Py_bytes_startswith(const char *str, Py_ssize_t len, PyObject *args)
+{
+    return _Py_bytes_tailmatch(str, len, "startswith", args, -1);
+}
+
+PyDoc_STRVAR_shared(_Py_endswith__doc__,
+"B.endswith(suffix[, start[, end]]) -> bool\n\
+\n\
+Return True if B ends with the specified suffix, False otherwise.\n\
+With optional start, test B beginning at that position.\n\
+With optional end, stop comparing B at that position.\n\
+suffix can also be a tuple of bytes to try.");
+
+PyObject *
+_Py_bytes_endswith(const char *str, Py_ssize_t len, PyObject *args)
+{
+    return _Py_bytes_tailmatch(str, len, "endswith", args, +1);
+}