Objects/stringlib/find.h

   1 /* stringlib: find/index implementation */
   2
   3 #ifndef STRINGLIB_FIND_H
   4 #define STRINGLIB_FIND_H
   5
   6 #ifndef STRINGLIB_FASTSEARCH_H
   7 #error must include "stringlib/fastsearch.h" before including this module
   8 #endif
   9
  10 Py_LOCAL_INLINE(Py_ssize_t)
  11 stringlib_find(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
  12                const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
  13                Py_ssize_t offset)
  14 {
  15     Py_ssize_t pos;
  16
  17     if (str_len < 0)
  18         return -1;
  19     if (sub_len == 0)
  20         return offset;
  21
  22     pos = fastsearch(str, str_len, sub, sub_len, FAST_SEARCH);
  23
  24     if (pos >= 0)
  25         pos += offset;
  26
  27     return pos;
  28 }
  29
  30 Py_LOCAL_INLINE(Py_ssize_t)
  31 stringlib_rfind(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
  32                 const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
  33                 Py_ssize_t offset)
  34 {
  35     Py_ssize_t pos;
  36
  37     if (str_len < 0)
  38         return -1;
  39     if (sub_len == 0)
  40         return str_len + offset;
  41
  42     pos = fastsearch(str, str_len, sub, sub_len, FAST_RSEARCH);
  43
  44     if (pos >= 0)
  45         pos += offset;
  46
  47     return pos;
  48 }
  49
  50 Py_LOCAL_INLINE(Py_ssize_t)
  51 stringlib_find_slice(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
  52                      const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
  53                      Py_ssize_t start, Py_ssize_t end)
  54 {
  55     if (start < 0)
  56         start += str_len;
  57     if (start < 0)
  58         start = 0;
  59     if (end > str_len)
  60         end = str_len;
  61     if (end < 0)
  62         end += str_len;
  63     if (end < 0)
  64         end = 0;
  65
  66     return stringlib_find(str + start, end - start, sub, sub_len, start);
  67 }
  68
  69 Py_LOCAL_INLINE(Py_ssize_t)
  70 stringlib_rfind_slice(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
  71                       const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
  72                       Py_ssize_t start, Py_ssize_t end)
  73 {
  74     if (start < 0)
  75         start += str_len;
  76     if (start < 0)
  77         start = 0;
  78     if (end > str_len)
  79         end = str_len;
  80     if (end < 0)
  81         end += str_len;
  82     if (end < 0)
  83         end = 0;
  84
  85     return stringlib_rfind(str + start, end - start, sub, sub_len, start);
  86 }
  87
  88 #if defined(STRINGLIB_STR) && !defined(FROM_BYTEARRAY)
  89
  90 Py_LOCAL_INLINE(int)
  91 stringlib_contains_obj(PyObject* str, PyObject* sub)
  92 {
  93     return stringlib_find(
  94         STRINGLIB_STR(str), STRINGLIB_LEN(str),
  95         STRINGLIB_STR(sub), STRINGLIB_LEN(sub), 0
  96         ) != -1;
  97 }
  98
  99 #endif /* STRINGLIB_STR */
 100
 101 #ifdef FROM_UNICODE
 102
 103 /*
 104 This function is a helper for the "find" family (find, rfind, index,
 105 rindex) of unicodeobject.c file, because they all have the same
 106 behaviour for the arguments.
 107
 108 It does not touch the variables received until it knows everything
 109 is ok.
 110
 111 Note that we receive a pointer to the pointer of the substring object,
 112 so when we create that object in this function we don't DECREF it,
 113 because it continues living in the caller functions (those functions,
 114 after finishing using the substring, must DECREF it).
 115 */
 116
 117 Py_LOCAL_INLINE(int)
 118 _ParseTupleFinds (PyObject *args, PyObject **substring,
 119                   Py_ssize_t *start, Py_ssize_t *end) {
 120     PyObject *tmp_substring;
 121     Py_ssize_t tmp_start = 0;
 122     Py_ssize_t tmp_end = PY_SSIZE_T_MAX;
 123     PyObject *obj_start=Py_None, *obj_end=Py_None;
 124
 125     if (!PyArg_ParseTuple(args, "O|OO:find", &tmp_substring,
 126          &obj_start, &obj_end))
 127         return 0;
 128
 129     /* To support None in "start" and "end" arguments, meaning
 130        the same as if they were not passed.
 131     */
 132     if (obj_start != Py_None)
 133         if (!_PyEval_SliceIndex(obj_start, &tmp_start))
 134             return 0;
 135     if (obj_end != Py_None)
 136         if (!_PyEval_SliceIndex(obj_end, &tmp_end))
 137             return 0;
 138
 139     tmp_substring = PyUnicode_FromObject(tmp_substring);
 140     if (!tmp_substring)
 141         return 0;
 142
 143     *start = tmp_start;
 144     *end = tmp_end;
 145     *substring = tmp_substring;
 146     return 1;
 147 }
 148
 149 #endif /* FROM_UNICODE */
 150
 151 #endif /* STRINGLIB_FIND_H */
 152
 153 /*
 154 Local variables:
 155 c-basic-offset: 4
 156 indent-tabs-mode: nil
 157 End:
 158 */