| 1 | #ifndef SCM_FOREIGN_H |
| 2 | #define SCM_FOREIGN_H |
| 3 | |
| 4 | /* Copyright (C) 2010, 2011, 2012, 2013 Free Software Foundation, Inc. |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public License |
| 8 | * as published by the Free Software Foundation; either version 3 of |
| 9 | * the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, but |
| 12 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 19 | * 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #include "libguile/__scm.h" |
| 23 | |
| 24 | /* A "foreign pointer" is a wrapped C pointer. It is represented by a |
| 25 | cell whose second word is a pointer. The first word has the |
| 26 | `scm_tc7_pointer' type code. |
| 27 | |
| 28 | The basic idea is that we can help the programmer to avoid cutting herself, |
| 29 | but we won't take away her knives. */ |
| 30 | |
| 31 | enum scm_t_foreign_type |
| 32 | { |
| 33 | SCM_FOREIGN_TYPE_VOID, |
| 34 | SCM_FOREIGN_TYPE_FLOAT, |
| 35 | SCM_FOREIGN_TYPE_DOUBLE, |
| 36 | SCM_FOREIGN_TYPE_UINT8, |
| 37 | SCM_FOREIGN_TYPE_INT8, |
| 38 | SCM_FOREIGN_TYPE_UINT16, |
| 39 | SCM_FOREIGN_TYPE_INT16, |
| 40 | SCM_FOREIGN_TYPE_UINT32, |
| 41 | SCM_FOREIGN_TYPE_INT32, |
| 42 | SCM_FOREIGN_TYPE_UINT64, |
| 43 | SCM_FOREIGN_TYPE_INT64, |
| 44 | SCM_FOREIGN_TYPE_LAST = SCM_FOREIGN_TYPE_INT64 |
| 45 | }; |
| 46 | |
| 47 | typedef enum scm_t_foreign_type scm_t_foreign_type; |
| 48 | |
| 49 | typedef void (*scm_t_pointer_finalizer) (void *); |
| 50 | |
| 51 | #define SCM_POINTER_P(x) (SCM_HAS_TYP7 (x, scm_tc7_pointer)) |
| 52 | #define SCM_VALIDATE_POINTER(pos, x) \ |
| 53 | SCM_MAKE_VALIDATE (pos, x, POINTER_P) |
| 54 | #define SCM_POINTER_VALUE(x) \ |
| 55 | ((void *) SCM_CELL_WORD_1 (x)) |
| 56 | |
| 57 | SCM_API void *scm_to_pointer (SCM pointer); |
| 58 | SCM_API SCM scm_from_pointer (void *, scm_t_pointer_finalizer); |
| 59 | |
| 60 | SCM_API SCM scm_alignof (SCM type); |
| 61 | SCM_API SCM scm_sizeof (SCM type); |
| 62 | SCM_API SCM scm_pointer_address (SCM pointer); |
| 63 | SCM_API SCM scm_pointer_to_scm (SCM pointer); |
| 64 | SCM_API SCM scm_scm_to_pointer (SCM scm); |
| 65 | SCM_API SCM scm_pointer_to_bytevector (SCM pointer, SCM type, |
| 66 | SCM offset, SCM len); |
| 67 | SCM_API SCM scm_set_pointer_finalizer_x (SCM pointer, SCM finalizer); |
| 68 | SCM_API SCM scm_bytevector_to_pointer (SCM bv, SCM offset); |
| 69 | |
| 70 | SCM_INTERNAL SCM scm_pointer_p (SCM obj); |
| 71 | SCM_INTERNAL SCM scm_make_pointer (SCM address, SCM finalizer); |
| 72 | SCM_INTERNAL void scm_i_pointer_print (SCM pointer, SCM port, |
| 73 | scm_print_state *pstate); |
| 74 | |
| 75 | SCM_INTERNAL SCM scm_dereference_pointer (SCM pointer); |
| 76 | SCM_INTERNAL SCM scm_string_to_pointer (SCM string, SCM encoding); |
| 77 | SCM_INTERNAL SCM scm_pointer_to_string (SCM pointer, SCM length, SCM encoding); |
| 78 | |
| 79 | \f |
| 80 | |
| 81 | /* Foreign functions */ |
| 82 | |
| 83 | /* The goal is to make it so that calling a foreign function doesn't cause any |
| 84 | heap allocation. That means we need native Scheme formats for all kinds of |
| 85 | arguments. |
| 86 | |
| 87 | For "value" types like s64 or f32, we just use native Scheme value types. |
| 88 | (Note that in both these cases, allocation is possible / likely, as the |
| 89 | value might need to be boxed, but perhaps we won't worry about that. Hmm.) |
| 90 | |
| 91 | For everything else, we use foreign pointers. This includes arrays, pointer |
| 92 | arguments and return vals, struct args and return vals, and out and in/out |
| 93 | arguments. |
| 94 | */ |
| 95 | |
| 96 | SCM_API SCM scm_pointer_to_procedure (SCM return_type, SCM func_ptr, |
| 97 | SCM arg_types); |
| 98 | SCM_API SCM scm_procedure_to_pointer (SCM return_type, SCM func_ptr, |
| 99 | SCM arg_types); |
| 100 | SCM_INTERNAL SCM scm_i_foreign_call (SCM foreign, const SCM *argv); |
| 101 | SCM_INTERNAL int scm_i_foreign_arity (SCM foreign, |
| 102 | int *req, int *opt, int *rest); |
| 103 | |
| 104 | \f |
| 105 | |
| 106 | SCM_INTERNAL void scm_register_foreign (void); |
| 107 | |
| 108 | |
| 109 | #endif /* SCM_FOREIGN_H */ |