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Diffstat (limited to 'unwind.h')
| -rw-r--r-- | unwind.h | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/unwind.h b/unwind.h new file mode 100644 index 00000000..8863fdff --- /dev/null +++ b/unwind.h @@ -0,0 +1,66 @@ +/* Copyright 2009 + * Kaz Kylheku <kkylheku@gmail.com> + * Vancouver, Canada + * All rights reserved. + * + * BSD License: + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. The name of the author may not be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +typedef union uw_frame uw_frame_t; +typedef enum uw_frtype uw_frtype_t; + +enum uw_frtype { UW_BLOCK }; + +struct uw_common { + uw_frame_t *up; + uw_frtype_t type; +}; + +struct uw_block { + uw_frame_t *up; + uw_frtype_t type; + obj_t *tag; + obj_t *result; + jmp_buf jb; +}; + +union uw_frame { + struct uw_common uw; + struct uw_block bl; +}; + +void uw_push_block(uw_frame_t *, obj_t *tag); +obj_t *uw_block_return(obj_t *tag, obj_t *result); +void uw_pop_frame(uw_frame_t *); + +#define uw_block_begin(TAG, RESULTVAR) \ + obj_t *RESULTVAR = nil; \ + { \ + uw_frame_t uw_fr; \ + uw_push_block(&uw_fr, TAG); \ + if (setjmp(uw_fr.bl.jb)) { \ + RESULTVAR = uw_fr.bl.result; \ + } else { + +#define uw_block_end \ + } \ + uw_pop_frame(&uw_fr); \ + } |