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      1 /* Implementing buffer protocol typemaps */
      2 
      3 /* %pybuffer_mutable_binary(TYPEMAP, SIZE)
      4  *
      5  * Macro for functions accept mutable buffer pointer with a size.
      6  * This can be used for both input and output. For example:
      7  *
      8  *      %pybuffer_mutable_binary(char *buff, int size);
      9  *      void foo(char *buff, int size) {
     10  *        for(int i=0; i<size; ++i)
     11  *          buff[i]++;
     12  *      }
     13  */
     14 
     15 %define %pybuffer_mutable_binary(TYPEMAP, SIZE)
     16 %typemap(in) (TYPEMAP, SIZE)
     17   (int res, Py_ssize_t size = 0, void *buf = 0) {
     18   res = PyObject_AsWriteBuffer($input, &buf, &size);
     19   if (res<0) {
     20     PyErr_Clear();
     21     %argument_fail(res, "(TYPEMAP, SIZE)", $symname, $argnum);
     22   }
     23   $1 = ($1_ltype) buf;
     24   $2 = ($2_ltype) (size/sizeof($*1_type));
     25 }
     26 %enddef
     27 
     28 /* %pybuffer_mutable_string(TYPEMAP, SIZE)
     29  *
     30  * Macro for functions accept mutable zero terminated string pointer.
     31  * This can be used for both input and output. For example:
     32  *
     33  *      %pybuffer_mutable_string(char *str);
     34  *      void foo(char *str) {
     35  *        while(*str) {
     36  *          *str = toupper(*str);
     37  *          str++;
     38  *      }
     39  */
     40 
     41 %define %pybuffer_mutable_string(TYPEMAP)
     42 %typemap(in) (TYPEMAP)
     43   (int res, Py_ssize_t size = 0, void *buf = 0) {
     44   res = PyObject_AsWriteBuffer($input, &buf, &size);
     45   if (res<0) {
     46     PyErr_Clear();
     47     %argument_fail(res, "(TYPEMAP, SIZE)", $symname, $argnum);
     48   }
     49   $1 = ($1_ltype) buf;
     50 }
     51 %enddef
     52 
     53 /* pybuffer_binary(TYPEMAP, SIZE)
     54  *
     55  * Macro for functions accept read only buffer pointer with a size.
     56  * This must be used for input. For example:
     57  *
     58  *      %pybuffer_binary(char *buff, int size);
     59  *      int foo(char *buff, int size) {
     60  *        int count = 0;
     61  *        for(int i=0; i<size; ++i)
     62  *          if (0==buff[i]) count++;
     63  *        return count;
     64  *      }
     65  */
     66 
     67 %define %pybuffer_binary(TYPEMAP, SIZE)
     68 %typemap(in) (TYPEMAP, SIZE)
     69   (int res, Py_ssize_t size = 0, const void *buf = 0) {
     70   res = PyObject_AsReadBuffer($input, &buf, &size);
     71   if (res<0) {
     72     PyErr_Clear();
     73     %argument_fail(res, "(TYPEMAP, SIZE)", $symname, $argnum);
     74   }
     75   $1 = ($1_ltype) buf;
     76   $2 = ($2_ltype) (size / sizeof($*1_type));
     77 }
     78 %enddef
     79 
     80 /* %pybuffer_string(TYPEMAP, SIZE)
     81  *
     82  * Macro for functions accept read only zero terminated string pointer.
     83  * This can be used for input. For example:
     84  *
     85  *      %pybuffer_string(char *str);
     86  *      int foo(char *str) {
     87  *        int count = 0;
     88  *        while(*str) {
     89  *          if (isalnum(*str))
     90  *            count++;
     91  *          str++;
     92  *      }
     93  */
     94 
     95 %define %pybuffer_string(TYPEMAP)
     96 %typemap(in) (TYPEMAP)
     97   (int res, Py_ssize_t size = 0, const void *buf = 0) {
     98   res = PyObject_AsReadBuffer($input, &buf, &size);
     99   if (res<0) {
    100     %argument_fail(res, "(TYPEMAP, SIZE)", $symname, $argnum);
    101   }
    102   $1 = ($1_ltype) buf;
    103 }
    104 %enddef
    105 
    106 
    107 
    108