/* Copyright 2009-2016 * Kaz Kylheku * Vancouver, Canada * All rights reserved. * * Redistribution of this software in source and binary forms, with or without * modification, is permitted provided that the following two conditions are met. * * Use of this software in any manner constitutes agreement with the disclaimer * which follows the two conditions. * * 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. * * 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. IN NO EVENT SHALL THE * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DAMAGES, HOWEVER CAUSED, * AND UNDER ANY THEORY OF LIABILITY, ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ typedef union uw_frame uw_frame_t; typedef enum uw_frtype { UW_BLOCK, UW_CAPTURED_BLOCK, UW_ENV, UW_CATCH, UW_HANDLE, UW_CONT_COPY, UW_DBG } uw_frtype_t; struct uw_common { uw_frame_t *up; uw_frtype_t type; }; struct uw_block { uw_frame_t *up; uw_frtype_t type; val tag; val result; val protocol; extended_jmp_buf jb; }; struct uw_dynamic_env { uw_frame_t *up; uw_frtype_t type; uw_frame_t *up_env; val func_bindings; val match_context; }; struct uw_catch { uw_frame_t *up; uw_frtype_t type; val matches; int visible; val sym; val args; uw_frame_t *cont; extended_jmp_buf jb; }; struct uw_handler { uw_frame_t *up; uw_frtype_t type; val matches; /* Same position as in uw_catch! */ int visible; /* Likewise. */ val fun; }; struct uw_cont_copy { uw_frame_t *up; uw_frtype_t type; mem_t *ptr; void (*copy)(mem_t *ptr, int parent); }; struct uw_debug { uw_frame_t *up; uw_frtype_t type; val func; struct args *args; val ub_p_a_pairs; val env; val data; val line; val chr; }; union uw_frame { struct uw_common uw; struct uw_block bl; struct uw_dynamic_env ev; struct uw_catch ca; struct uw_handler ha; struct uw_cont_copy cp; struct uw_debug db; }; void uw_push_block(uw_frame_t *, val tag); void uw_push_env(uw_frame_t *); val uw_get_func(val sym); val uw_set_func(val sym, val value); val uw_get_match_context(void); val uw_set_match_context(val context); val uw_block_return_proto(val tag, val result, val protocol); INLINE val uw_block_return(val tag, val result) { return uw_block_return_proto(tag, result, nil); } val uw_block_abscond(val tag, val result); void uw_push_catch(uw_frame_t *, val matches); void uw_push_handler(uw_frame_t *, val matches, val fun); noreturn val uw_throw(val sym, val exception); noreturn val uw_throwv(val sym, struct args *); noreturn val uw_throwf(val sym, val fmt, ...); noreturn val uw_throwfv(val sym, val fmt, struct args *); noreturn val uw_errorf(val fmt, ...); noreturn val uw_errorfv(val fmt, struct args *args); val uw_register_subtype(val sub, val super); val uw_exception_subtype_p(val sub, val sup); void uw_continue(uw_frame_t *curr, uw_frame_t *target); void uw_push_debug(uw_frame_t *, val func, struct args *, val ub_p_a_pairs, val env, val data, val line, val chr); void uw_pop_frame(uw_frame_t *); void uw_pop_block(uw_frame_t *, val *pret); void uw_pop_until(uw_frame_t *); uw_frame_t *uw_current_frame(void); uw_frame_t *uw_current_exit_point(void); val uw_get_frames(void); val uw_find_frame(val extype, val frtype); val uw_invoke_catch(val catch_frame, val sym, struct args *); val uw_capture_cont(val tag, val fun, val ctx_form); void uw_push_cont_copy(uw_frame_t *, mem_t *ptr, void (*copy)(mem_t *ptr, int parent)); void uw_init(void); void uw_late_init(void); noreturn val type_mismatch(val, ...); #define uw_mark_frame \ uw_frame_t *uw_top = uw_current_frame() #define uw_fast_return(VAL) \ do { \ uw_pop_until(uw_top); \ return VAL; \ } while (0) #define uw_block_begin(TAG, RESULTVAR) \ obj_t *RESULTVAR = nil; \ do { \ uw_frame_t uw_blk; \ obj_t **uw_rslt = &RESULTVAR; \ uw_push_block(&uw_blk, TAG); \ if (extended_setjmp(uw_blk.bl.jb)) { \ RESULTVAR = uw_blk.bl.result; \ } else { \ do { } while (0) #define uw_block_end \ } \ uw_pop_block(&uw_blk, uw_rslt); \ } while (0) #define uw_env_begin \ do { \ uw_frame_t uw_env; \ uw_push_env(&uw_env) #define uw_env_end \ uw_pop_frame(&uw_env); \ } while (0) #define uw_simple_catch_begin \ do { \ uw_frame_t uw_catch; \ uw_push_catch(&uw_catch, nil); \ switch (extended_setjmp(uw_catch.ca.jb)) { \ case 0: #define uw_catch_begin(MATCHES, SYMVAR, \ EXCVAR) \ do { \ obj_t *SYMVAR = nil; \ obj_t *EXCVAR = nil; \ uw_frame_t uw_catch; \ uw_push_catch(&uw_catch, MATCHES); \ switch (extended_setjmp(uw_catch.ca.jb)) { \ case 0: #define uw_catch(SYMVAR, EXCVAR) \ goto uw_unwind_label; \ break; \ case 2: \ EXCVAR = uw_catch.ca.args; \ SYMVAR = uw_catch.ca.sym; \ (void) SYMVAR; \ /* prevent looping */ \ uw_catch.ca.matches = nil; #define uw_unwind \ /* suppress unused label warning */ \ goto uw_unwind_label; \ uw_unwind_label: \ case 1: \ /* prevent looping */ \ uw_catch.ca.visible = 0; #define uw_catch_end \ break; \ default: \ abort(); \ } \ if (uw_catch.ca.cont) \ uw_continue(&uw_catch, \ uw_catch.ca.cont); \ uw_pop_frame(&uw_catch); \ } while(0) #define internal_error(STR) \ do { \ extern obj_t *num(cnum); \ uw_throwf(internal_error_s, \ lit("~a:~a ~a"), \ lit(__FILE__), \ num(__LINE__), lit(STR), \ nao); \ } while (0) #define type_assert(EXPR, ARGS) \ if (!(EXPR)) type_mismatch ARGS #define bug_unless(EXPR) \ if (!(EXPR)) \ internal_error("assertion " \ #EXPR \ " failed")