1  /* stringlib: find/index implementation */
       2  
       3  #ifndef STRINGLIB_FASTSEARCH_H
       4  #error must include "stringlib/fastsearch.h" before including this module
       5  #endif
       6  
       7  Py_LOCAL_INLINE(Py_ssize_t)
       8  STRINGLIB(find)(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
       9                 const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
      10                 Py_ssize_t offset)
      11  {
      12      Py_ssize_t pos;
      13  
      14      assert(str_len >= 0);
      15      if (sub_len == 0)
      16          return offset;
      17  
      18      pos = FASTSEARCH(str, str_len, sub, sub_len, -1, FAST_SEARCH);
      19  
      20      if (pos >= 0)
      21          pos += offset;
      22  
      23      return pos;
      24  }
      25  
      26  Py_LOCAL_INLINE(Py_ssize_t)
      27  STRINGLIB(rfind)(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
      28                  const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
      29                  Py_ssize_t offset)
      30  {
      31      Py_ssize_t pos;
      32  
      33      assert(str_len >= 0);
      34      if (sub_len == 0)
      35          return str_len + offset;
      36  
      37      pos = FASTSEARCH(str, str_len, sub, sub_len, -1, FAST_RSEARCH);
      38  
      39      if (pos >= 0)
      40          pos += offset;
      41  
      42      return pos;
      43  }
      44  
      45  Py_LOCAL_INLINE(Py_ssize_t)
      46  STRINGLIB(find_slice)(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
      47                       const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
      48                       Py_ssize_t start, Py_ssize_t end)
      49  {
      50      return STRINGLIB(find)(str + start, end - start, sub, sub_len, start);
      51  }
      52  
      53  Py_LOCAL_INLINE(Py_ssize_t)
      54  STRINGLIB(rfind_slice)(const STRINGLIB_CHAR* str, Py_ssize_t str_len,
      55                        const STRINGLIB_CHAR* sub, Py_ssize_t sub_len,
      56                        Py_ssize_t start, Py_ssize_t end)
      57  {
      58      return STRINGLIB(rfind)(str + start, end - start, sub, sub_len, start);
      59  }
      60  
      61  #ifdef STRINGLIB_WANT_CONTAINS_OBJ
      62  
      63  Py_LOCAL_INLINE(int)
      64  STRINGLIB(contains_obj)(PyObject* str, PyObject* sub)
      65  {
      66      return STRINGLIB(find)(
      67          STRINGLIB_STR(str), STRINGLIB_LEN(str),
      68          STRINGLIB_STR(sub), STRINGLIB_LEN(sub), 0
      69          ) != -1;
      70  }
      71  
      72  #endif /* STRINGLIB_WANT_CONTAINS_OBJ */
      73  
      74  /*
      75  This function is a helper for the "find" family (find, rfind, index,
      76  rindex) and for count, startswith and endswith, because they all have
      77  the same behaviour for the arguments.
      78  
      79  It does not touch the variables received until it knows everything
      80  is ok.
      81  */
      82  
      83  #define FORMAT_BUFFER_SIZE 50
      84  
      85  Py_LOCAL_INLINE(int)
      86  STRINGLIB(parse_args_finds)(const char * function_name, PyObject *args,
      87                             PyObject **subobj,
      88                             Py_ssize_t *start, Py_ssize_t *end)
      89  {
      90      PyObject *tmp_subobj;
      91      Py_ssize_t tmp_start = 0;
      92      Py_ssize_t tmp_end = PY_SSIZE_T_MAX;
      93      PyObject *obj_start=Py_None, *obj_end=Py_None;
      94      char format[FORMAT_BUFFER_SIZE] = "O|OO:";
      95      size_t len = strlen(format);
      96  
      97      strncpy(format + len, function_name, FORMAT_BUFFER_SIZE - len - 1);
      98      format[FORMAT_BUFFER_SIZE - 1] = '\0';
      99  
     100      if (!PyArg_ParseTuple(args, format, &tmp_subobj, &obj_start, &obj_end))
     101          return 0;
     102  
     103      /* To support None in "start" and "end" arguments, meaning
     104         the same as if they were not passed.
     105      */
     106      if (obj_start != Py_None)
     107          if (!_PyEval_SliceIndex(obj_start, &tmp_start))
     108              return 0;
     109      if (obj_end != Py_None)
     110          if (!_PyEval_SliceIndex(obj_end, &tmp_end))
     111              return 0;
     112  
     113      *start = tmp_start;
     114      *end = tmp_end;
     115      *subobj = tmp_subobj;
     116      return 1;
     117  }
     118  
     119  #undef FORMAT_BUFFER_SIZE