summaryrefslogtreecommitdiffstats
path: root/Objects/stringlib/find.h
blob: f915296cae61350575c77d01a9c85ad34acba392 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
/* stringlib: find/index implementation */

#ifndef STRINGLIB_FIND_H
#define STRINGLIB_FIND_H

#ifndef STRINGLIB_FASTSEARCH_H
#error must include "stringlib/fastsearch.h" before including this module
#endif

Py_LOCAL_INLINE(Py_ssize_t)
stringlib_find(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
               const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
               Py_ssize_t offset)
{
    Py_ssize_t pos;

    if (str_len < 0)
        return -1;
    if (sub_len == 0)
        return offset;

    pos = fastsearch(str, str_len, sub, sub_len, -1, FAST_SEARCH);

    if (pos >= 0)
        pos += offset;

    return pos;
}

Py_LOCAL_INLINE(Py_ssize_t)
stringlib_rfind(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
                const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
                Py_ssize_t offset)
{
    Py_ssize_t pos;

    if (str_len < 0)
        return -1;
    if (sub_len == 0)
        return str_len + offset;

    pos = fastsearch(str, str_len, sub, sub_len, -1, FAST_RSEARCH);

    if (pos >= 0)
        pos += offset;

    return pos;
}

/* 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)
stringlib_find_slice(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
                     const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
                     Py_ssize_t start, Py_ssize_t end)
{
    ADJUST_INDICES(start, end, str_len);
    return stringlib_find(str + start, end - start, sub, sub_len, start);
}

Py_LOCAL_INLINE(Py_ssize_t)
stringlib_rfind_slice(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
                      const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
                      Py_ssize_t start, Py_ssize_t end)
{
    ADJUST_INDICES(start, end, str_len);
    return stringlib_rfind(str + start, end - start, sub, sub_len, start);
}

#ifdef STRINGLIB_WANT_CONTAINS_OBJ

Py_LOCAL_INLINE(int)
stringlib_contains_obj(PyObject* str, PyObject* sub)
{
    return stringlib_find(
        STRINGLIB_STR(str), STRINGLIB_LEN(str),
        STRINGLIB_STR(sub), STRINGLIB_LEN(sub), 0
        ) != -1;
}

#endif /* STRINGLIB_WANT_CONTAINS_OBJ */

#if STRINGLIB_IS_UNICODE

/*
This function is a helper for the "find" family (find, rfind, index,
rindex) of unicodeobject.c file, because they all have the same 
behaviour for the arguments.

It does not touch the variables received until it knows everything 
is ok.

Note that we receive a pointer to the pointer of the substring object,
so when we create that object in this function we don't DECREF it,
because it continues living in the caller functions (those functions, 
after finishing using the substring, must DECREF it).
*/

Py_LOCAL_INLINE(int)
_ParseTupleFinds (PyObject *args, PyObject **substring, 
                  Py_ssize_t *start, Py_ssize_t *end) {
    PyObject *tmp_substring;
    Py_ssize_t tmp_start = 0;
    Py_ssize_t tmp_end = PY_SSIZE_T_MAX;
    PyObject *obj_start=Py_None, *obj_end=Py_None;

    if (!PyArg_ParseTuple(args, "O|OO:find", &tmp_substring,
         &obj_start, &obj_end))
        return 0;

    /* To support None in "start" and "end" arguments, meaning
       the same as if they were not passed.
    */
    if (obj_start != Py_None)
        if (!_PyEval_SliceIndex(obj_start, &tmp_start))
            return 0;
    if (obj_end != Py_None)
        if (!_PyEval_SliceIndex(obj_end, &tmp_end))
            return 0;

    tmp_substring = PyUnicode_FromObject(tmp_substring);
    if (!tmp_substring)
        return 0;

    *start = tmp_start;
    *end = tmp_end;
    *substring = tmp_substring;
    return 1;
}

#endif /* STRINGLIB_IS_UNICODE */

#endif /* STRINGLIB_FIND_H */