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* Copyright year bump 2019.Kaz Kylheku2019-01-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * LICENSE, LICENSE-CYG, METALICENSE, Makefile, args.c, args.h, arith.c, arith.h, buf.c, buf.h, cadr.c, cadr.h, combi.c, combi.h, configure, debug.c, debug.h, eval.c, eval.h, ffi.c, ffi.h, filter.c, filter.h, ftw.h, gc.c, gc.h, glob.c, glob.h, hash.c, hash.h, itypes.c, itypes.h, jmp.S, lib.c, lib.h, lisplib.c, lisplib.h, match.c, match.h, parser.c, parser.h, parser.l, parser.y, protsym.c, rand.c, rand.h, regex.c, regex.h, share/txr/stdlib/asm.tl, share/txr/stdlib/awk.tl, share/txr/stdlib/build.tl, share/txr/stdlib/cadr.tl, share/txr/stdlib/compiler.tl, share/txr/stdlib/conv.tl, share/txr/stdlib/doloop.tl, share/txr/stdlib/error.tl, share/txr/stdlib/except.tl, share/txr/stdlib/ffi.tl, share/txr/stdlib/getopts.tl, share/txr/stdlib/getput.tl, share/txr/stdlib/hash.tl, share/txr/stdlib/ifa.tl, share/txr/stdlib/keyparams.tl, share/txr/stdlib/op.tl, share/txr/stdlib/package.tl, share/txr/stdlib/path-test.tl, share/txr/stdlib/place.tl, share/txr/stdlib/pmac.tl, share/txr/stdlib/socket.tl, share/txr/stdlib/stream-wrap.tl, share/txr/stdlib/struct.tl, share/txr/stdlib/tagbody.tl, share/txr/stdlib/termios.tl, share/txr/stdlib/trace.tl, share/txr/stdlib/txr-case.tl, share/txr/stdlib/type.tl, share/txr/stdlib/vm-param.tl, share/txr/stdlib/with-resources.tl, share/txr/stdlib/with-stream.tl, share/txr/stdlib/yield.tl, signal.c, signal.h, socket.c, socket.h, stream.c, stream.h, struct.c, struct.h, strudel.c, strudel.h, sysif.c, sysif.h, syslog.c, syslog.h, termios.c, termios.h, txr.1, txr.c, txr.h, unwind.c, unwind.h, utf8.c, utf8.h, vm.c, vm.h, vmop.h, win/cleansvg.txr: Extended Copyright line to 2018.
* Eliminate ALLOCA_H.Kaz Kylheku2018-12-311-1/+1
| | | | | | | | | | | | | * configure: Instead of generating a definition of ALLOCA_H, generate the variable HAVE_ALLOCA_<name> with a value of 1, where <name> is one of stdlib, alloca or malloc. * alloca.h: New header. * args.c, eval.c, ffi.c ffi.c, ftw.c, hash.c, lib.c, match.c, parser.c, parser.y, regex.c, socket.c, stream.c, struct.c, sysif.c, syslog.c, termios.c, unwind.c, vm.c: Include "alloca.h" instead of ALLOCA_H.
* Drastically reduce inclusion of <dirent.h>.Kaz Kylheku2018-12-111-1/+0
| | | | | | | | | | | | | | | | | | | The <dirent.h> header is included all over the place because it is needed by a single declaration in stream.h. That declaration is for a function that is only called within stream.c, so we make it internal. Now only stream.c has to include <dirent.h>. * buf.c, debug.c, eval.c, ffi.c, filter.c, gc.c, gencadr.txr, hash.c, lib.c, lisplib.c, match.c, parser.c, regex.c, socket.c, struct.c, strudel.c, sysif.c, syslog.c, termios.c, txr.c, unwind.c, vm.c: Remove #include <dirent.h>. * cadr.c: Regenerated. * stream.c (make_dir_stream): Make external function static. * stream.h (make_dir_stream): Declaration updated.
* Better identify functions that misuse COBJ-s and hashes.Kaz Kylheku2018-11-071-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In this patch, the cobj_handle, cobj_ops and variants of gethash get an additional argument to identify the caller. Many functions are updated to pass this down. * buf.c (buf_strm): Pass self name to cobj_handle. * eval.c (env_fbind, env_vbind, rt_defvarl, me_case): Pass self name to gethash_c or gethash_e. (load): Pass self name to read_eval_stream and read_compiled_file. (reg_symacro): Pass situation-identifying string to gethash_c. * ffi.c (ffi_type_struct_checked, ffi_closure_struct_checked, ffi_call_desc_checked, uni_struct_checked): Take self name parameter, and pass down to cobj_handle. (ffi_get_type, ffi_get_lisp_type): Take self name and pass down to ffi_type_struct_checked. (union_get_ptr): Take self name and pass to uni_struct_checked. (ffi_union_in, ffi_union_put): Pass self name to union_get_ptr. (ffi_type_compile): Pass self name to ffi_get_lisp_type. (ffi_make_call_desc): Pass self name to ffi_type_struct_checked, ffi_get_type and ffi_call_desc_checked. (ffi_make_closure): Pass self name to ffi_call_desc_checked. (ffi_closure_get_fptr): Take self name, pass to ffi_closure_struct_checked. (ffi_typedef, ffi_size, ffi_alignof, ffi_offsetof, ffi_arraysize, ffi_elemsize, ffi_elemtype, ffi_put_into, ffi_put, ffi_in, ffi_get, ffi_out, make_carray): Pass self name to ffi_closure_struct_checked. (carray_struct_checked): Take self name, pass to cobj_handle. (carray_set_length, carray_dup, carray_own, carray_free, carray_type, length_carray, copy_carray, carray_ptr, buf_carray, vec_carray, list_carray, carray_ref, carray_refset, carray_sub, carray_replace, carray_get_common, carray_put_common, unum_carray, num_carray, put_carray, fill_carray): Pass self name to carray_struct_checked. (carray_blank, carray_buf, carray_cptr): Pass self name ffi_type_struct_checked. (carray_pun): Pass self name to carray_struct_checked and ffi_type_struct_checked. (make_union): Pass self name to ffi_type_struct_checked. (union_members, union_get, union_put, union_in, union_out): Pass self name to uni_struct_checked. (make_zstruct, zero_fill, put_obj, get_obj, fill_obj): Pass self-name to ffi_type_struct_checked. * ffi.h (ffi_closure_get_fptr, union_get_ptr): Declarations updated. * filter.c (trie_add): Pass self-name to gethash_l. * hash.c (make_similar_hash, copy_hash, hash_count, get_hash_userdata, set_hash_userdata, hash_begin, hash_next, hash_uni, hash_diff, hash_isec): Pass self name to cobj_handle. (gethash_c, gethash_e): Take self name parameter and pass down to cobj_handle. (gethash_f): Take self parameter and pass down to gethash_e. (gethash, inhash, gethash_n, sethash, pushhash, remhash, clearhash, hash_update_1): Pass self name to gethash_e or gethash_c. * hash.h (gethash_c, gethash_e, gethash_f): Declarations updated. (gethash_l): Take self name, and pass down to gethash_c. * lib.c (class_check): Take self name parameter and use in type mismatch diagnostic. (use_sym, unuse_sym, symbol_needs_prefix, find_symbol, intern, unintern, intern_fallback, unique, in, sel, obj_print_impl, populate_obj_hash, obj_hash_merge): Pass self name to gethash_f or gethash_l. (symbol_visible, obj_init): Pass situation-identifying string to gethash_e. (cobj_handle, cobj_ops): Take self name parameter and pass down to class_check. * lib.h (class_check, cobj_handle, cobj_ops): Declarations updated. * match.c (v_load): Pass self name to read_compiled_file and read_eval_stream. * parser.c (get_parser_impl): Take self name and pass to cobj_handle. (ensure_parser): Pass situation-identifying string to gethash_c. (parser_circ_def): Pass self-name to gethash_c. (lisp_parser_impl): Pass self name to get_parser_impl and class_check. (lisp_parse, nread, iread): Pass self-name to lisp_parser_impl. (read_file_common): Take self name parameter and pass down to get_parser_impl. (read_eval_stream, read_compiled_file): Take self name and pass down to read_file_common. (load_rcfile): Pass situation-identifying string to read_eval_streem. (get_visible_syms): Pass situation-identifying string to gethash_c. (parser_errors, parser_eof): Pass self name to cobj_handle. * parser.h (read_eval_stream, read_compiled_file): Declarations updated. * parser.y (rlset): Pass self name to gethash_c. * rand.c (make_random_state, random_state_get_vec,l random_fixnum, random_float): Pass self name to cobj_handle. * regex.c (regex_source, regex_print, regex_run): Pass self-name to cobj_handle. (regex_machine_init): Take self name param and pass to cobj_handle. (search_regex, match_regex, match_regex_right, regex_prefix_match, read_until_match): Pass self-name to regex_machine_init. * stream.c (stdio_get_fd): Pass self name to cobj_handle. (generic_get_line): Get COBJ operations via unsafe, diret object access rather than cobj_ops. (set_mode_props): Get object handle via unsafe, direct object access. (stream_fd, sock_family, sock_type, sock_peer, set_sock_peer, get_string_from_stream, get_list_from_stream, stream_set_prop, stream_get_prop, close_stream, get_error, get_error_str, clear_error, get_line, get_char, get_byte, unget_char, unget_byte, put_buf, fill_buf, put_string, put_char, put_byte, flush_stream, seek_stream, truncate_stream, get_indent_mode, test_set_indent_mode, set_indent_mode, get_indent, set_indent, inc_indent, width_check, force_break, get_set_ctx, get_ctx): Pass self name to cobj_ops. (make_delegate_stream): Take self name parameter, pass down to cobj_ops. (record_adapter): Pass self name down to make_delegate_stream. (format): Pass self name to class_check. * struct.c (stype_handle): Pass self name to cobj_handle. (make_struct_type): Pass self name to class_check. * txr.c (read_eval_stream_noerr): Take self name parameter, pass to read_eval_stream. (txr_main): Pass istuation-identifying string to read_compiled_file and read_eval_stream_noerr. * unwind.c (revive_cont): Pass self-name to cobj_handle. * vm.c (vm_desc_struct): Take self name parameter, pass to cobj_handle. (vm_desc_nlevels, vm_desc_nregs, vm_desc_bytecode, vm_desc_datavec, vm_desc_symvec, vm_execute_toplevel, vm_execute_closure, vm_closure_entry): Pass self name to vm_desc_struct. (vm_closure_struct): Take self name parameter, pass to cobj_handle.
* defvar: warn about prior lexical uses.Kaz Kylheku2018-10-261-0/+5
| | | | | | | | | | | | | | | | | | | Now that the compiler has a more efficient treatment of global lexical variables, code which accesses global variables that have not yet been defined will misbehave if the intent is to for those variables to be dynamically scoped. There is such a bug in the op expander, in fact. * eval.c (me_def_variable): When defvar/defparm are expanding, they now check whether there is an outstanding unbound warning against the variable. If so, then a warning is issued that the variable was previously used lexically and is now being marked special. * unwind.c (uw_warning_exists): New function. * unwind.h (uw_warning_exists): Declared.
* continuations: don't fixup pointers if delta is zero.Kaz Kylheku2018-03-291-1/+1
| | | | | | * unwind.c (revive_cont): If delta is zero, skip the loop. This is an important optimization. The delta zero case can occur frequently; I have observed it.
* vm: integrate with delimited continuations.Kaz Kylheku2018-03-291-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It doesn't Just Work out of the box. Here is why. The struct vm state is declared somewhere on the stack, and then the vm executes various recursive functions. A block is established by vm_block(). Then if a continuation is captured up to that block, it will not include that part of the stack which holds the VM state. When the continuation is restarted, the struct vm * pointers inside the stack will be garbage. The solution: when a continuation is captured to a prompt that is set up by the VM block instruction (vm_block function), we put information into the block which says "don't just capture me plus some slack: please capture the stack all the way up to this specific address here". That address, of course, is just past the VM state, ensuring that the VM state is included in the snapshot. In short: a delimited continuation terminating in a prompt set up by the VM just include the entire VM context from the stack frame where the struct vm on down (i.e. up the stack) to the capture point. * unwind.c (uw_push_block): Initialize cont_bottom member to zero. Interpreted blocks leave this as zero. Blocks set up by the VM override it. (revive_cont): Critical: the range check must include the orig_end endpoint, because when the struct vm is captured into the continuation it is right at the end of the capture memory, and the prompt block's cont_bottom member points exactly to orig_end: one element past the struct vm. The cont_bottom member must be adjusted by delta so that continuations captured by the revived VM inside the continuation get the adjusted cont_bottom at their current stack location. (capture_cont): If the block is publishing a non-zer cont_bottom value, then take that value if it is a higher address than the lim (including the UW_CONT_FRAME_AFTER slack). * unwind.h (struct uw_block): New member, cont_bottom. By means of this, a block can indicate a higher address to which a continuation capture can extend. * vm.c (vm_block): Publish the address one byte past the virtual machine state as the stack bottom for continuations.
* unwind: better debugging of exceptions.Kaz Kylheku2018-03-121-0/+9
| | | | | | | | | | | | | | | Once upon a time when we didn't have continuable warning exceptions, it was easy to debug internal error throws in TXR: just set a breakpoint on uw_throw and catch it in the debugger. This approach became unworkable with uw_throw being executed numerous times as part of the ordinary program control flow. With this change, we get that debugging experience back. * unwind.c (uw_break_on_error): New static variable. (uw_throw): If the break-on-error variable is set and we are processing an exception derived from error, then call the breakpt function.
* Copyright year bump 2018.Kaz Kylheku2018-02-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * LICENSE, LICENSE-CYG, METALICENSE, Makefile, args.c, args.h, arith.c, arith.h, buf.c, buf.h, cadr.c, cadr.h, combi.c, combi.h, configure, debug.c, debug.h, eval.c, eval.h, ffi.c, ffi.h, filter.c, filter.h, ftw.c, ftw.h, gc.c, gc.h, glob.c, glob.h, hash.c, hash.h, itypes.c, itypes.h, jmp.S, lib.c, lib.h, lisplib.c, lisplib.h, match.c, match.h, parser.c, parser.h, parser.l, parser.y, protsym.c, rand.c, rand.h, regex.c, regex.h, share/txr/stdlib/awk.tl, share/txr/stdlib/build.tl, share/txr/stdlib/cadr.tl, share/txr/stdlib/conv.tl, share/txr/stdlib/doloop.tl, share/txr/stdlib/error.tl, share/txr/stdlib/except.tl, share/txr/stdlib/ffi.tl, share/txr/stdlib/getopts.tl, share/txr/stdlib/getput.tl, share/txr/stdlib/hash.tl, share/txr/stdlib/ifa.tl, share/txr/stdlib/keyparams.tl, share/txr/stdlib/op.tl, share/txr/stdlib/package.tl, share/txr/stdlib/path-test.tl, share/txr/stdlib/place.tl, share/txr/stdlib/pmac.tl, share/txr/stdlib/socket.tl, share/txr/stdlib/stream-wrap.tl, share/txr/stdlib/struct.tl, share/txr/stdlib/tagbody.tl, share/txr/stdlib/termios.tl, share/txr/stdlib/txr-case.tl, share/txr/stdlib/type.tl, share/txr/stdlib/with-resources.tl, share/txr/stdlib/with-stream.tl, share/txr/stdlib/yield.tl, signal.c, signal.h, socket.c, socket.h, stream.c, stream.h, struct.c, struct.h, strudel.c, strudel.h, sysif.c, sysif.h, syslog.c, syslog.h, termios.c, termios.h, txr.1, txr.c, txr.h, unwind.c, unwind.h, utf8.c, utf8.h, win/cleansvg.txr: Extended Copyright line to 2018.
* Use rplaca and rplacd instead of set over car_l/cdr_l.Kaz Kylheku2018-01-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | This reduces the proliferation of car_l and cdr_l. With this change, nreverse should work on chains of objects that implement rplacd. * combi.c (comb_gen_fun_common, rcomb_gen_fun_common): Use rplaca. * eval.c (mappendv, mapdov): Likewise * hash.c (hash_equal_op): Likewise. * lib.c (nreverse, acons_new, aconsql_new, sort_list): Use rplaca and rplacd. * match.c (dest_set, v_gather, v_collect, v_flatten, v_cat, v_output, v_filter): Likewise * parser.c (ensure_parser): Use sys_rplacd. * unwind.c (uw_register_subtype): Use rplacd.
* Revising out-of-memory handling.Kaz Kylheku2017-08-181-0/+1
| | | | | | | | | | | | | | | | | | | | | We don't want to be aborting on OOM, but throwing an exception. * lib.c (alloc_error_s): New symbol variable. (oom_realloc): Global variable removed. (oom): New static function. (chk_malloc, chk_malloc_gc_more, chk_calloc, chk_realloc): Call oom instead of removed oom_realloc handler. (env): Throw alloc-error rather than error by calling oom. (obj_init): Initialize alloc_error_s. (init): Drop function pointer argument; do not initialize removed oom_realloc. * lib.h (alloc_error_s): Declared. (oom_realloc): Declaration removed. (init): Declaration updated. * txr.1: Type tree diagram includes alloc-error.
* Get continuations working on aarch64.Kaz Kylheku2017-08-161-14/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | * unwind.c (UW_CONT_FRAME_BEFORE, UW_CONT_FRAME_AFTER): New preprocessor symbols. (revive_cont): The "frame slack" zero-filled padding logic is replaced by capturing an actual part of the real stack before the uw_stack unwind frame. On aarch64, there is content there we must actually capture. Experiment shows that exactly 128 bytes is enough, and that corresponds to the frame_slack value. (capture_cont): Capture UW_CONT_FRAME_BEFORE bytes before the uw_stack unwind frame location. Also, the "capture_extra" is replaced by UW_CONT_FRAME_AFTER constant, to harmonize. * unwind.h (UW_FRAME_ALIGN): New preprocessor symbol. (union uw_frame): On aarch64, we ask the compiler, via a GCC-specific attribute syntax, to align the address of frame objects to a 16 byte boundary. This solves a crash in the continuation code. Continuation capture is keyed to unwind frame addresses. When a captured continuation is revived onto the stack, the delta between its original address and the revive address must be a multiple of 16. The reason is that this preserves the stack and frame pointer alignment. Certain instructions on the aarch64, require the stack pointer to be 16 byte aligned. There are other ways we could achieve this, but the easiest is to align the original frames to 16 bytes.
* cobj: rename poorly named default operation.Kaz Kylheku2017-05-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Renaming cobj_hash_op to cobj_eq_hash_op. This function is only appropriate to use with COBJ objects which use eq as their equal funtion. I've spotted one instance of an inappropriate use which have to be addressed by a different commit: the equal function is other than eq, but cobj_hash_op is used for the equal hash. * lib.h (cobj_hash_op): Declaration renamed to cobj_eq_hash_op. * hash.c (cobj_hash_op): Renamed to cobj_eq_hash_op. (hash_iter_ops): Refer to renamed cobj_hash_eq_op. * ffi.c (ffi_type_builtin_ops, ffi_type_struct_ops, ffi_type_ptr_ops, ffi-closure_ops, ffi_call_desc_ops): Likewise. * lib.c (cptr_ops): Likewise. * parser.c (parser_ops): Likewise. * rand.c (random_state_ops): Likewise. * regex.c (char_set_ops, regex_obj_ops): Likewise. * socket.c (dgram_strm_ops): Likewise. * stream.c (null_ops, stdio_ops, tail_ops, pipe_ops, dir_ops, string_in_ops, byte_in_ops, strlist_in_ops, string_out_ops, strlist_out_ops, cat_stream_ops, record_adapter_ops): Likewise. * struct.c (struct_type_ops): Likewise. * sysif.c (cptr_dl_ops): Likewise. * syslog.c (syslog_strm_ops): Likewise. * unwind.c (cont_ops): Likewise.
* Restore package and package alist in handlers.Kaz Kylheku2017-03-181-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When setting up a handler frame, we note down the current package alist and package in the frame. Then when invoking the handler, we rebind the *package* and *package-alist* special variables. This is a needed security measure for sandboxing. Since handlers do not unwind (and therefore do not restore special variables) a handler in sandboxed code could catch an exception from non-sandboxed code that has changed *package* or *package-alist*, and take advantage of those changed values to escape from the sandbox. * unwind.c (uw_push_handler): Store current package and package-alist into new fields in the handler frame. (invoke_handler): Set up a new dynamic environment and bind *package* and *package-alist* around the handler call, to the values noted in the frame. Thus the handler executes with whatever package context was current when the handler was established. * unwind.h (struct uw_handler): New members, package and package_alist. * txr.1: Add paragraph to Exception Handling about this issue.
* Rename badly named default_bool_argKaz Kylheku2017-03-171-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * lib.h (default_bool_arg): Inline function renamed to default_null_arg. * eval.c (if_fun, pad, ginterate, giterate, range_star, range, constantp, macroexpand_1, macro_form_p, expand_with_free_refs, do_expand, eval_intrinsic, func_get_name, make_env_intrinsic): Follow rename. * arith.c (lognot): Likewise. * gc.c (gc_finalize): Likewise. * glob.c (glob_wrap): Likewise. * hash.c (group_reduce, gethash_n): Likewise. * lib.c (print, multi_sort, lazy_str, vector, iff, tok_str, split_str_keep, search_str, remove_if, val): Likewise. * match.c (match_fun): Likewise. * parser.c (lisp_parse_impl, regex_parse): Likewise. * rand.c (make_random_state): Likewise. * regex.c (read_until_match, search_regex, regex_compile): Likewise. * socket.c (sock_accept, sock_connect): Likewise. * stream.c (open_files_star, open_files, run, open_process, open_tail, get_string, record_adapter): Likewise. * struct.c (static_slot_ensure, static_slot_ens_rec, clear_struct, make_struct_type): Likewise. * sysif.c (exec_wrap, errno_wrap, cobj_ops_init): Likewise. * unwind.c (uw_capture_cont, uw_find_frames_impl): Likewise.
* Use non-hacky representation for deferrable warnings.Kaz Kylheku2017-02-101-12/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Deferrable warnings now get their own subtype, defr-warning. The tag is a regular argument: no funny dotted argument list. * eval.c (eval_defr_warn): Throw new style deferrable warning. (me_op, no_warn_expand): Catch defr-warning rather than warning. Use uw_muffle_warning to suppress it. (gather_free_refs): Parse new representation of deferrable warning. (expand_with_free_refs): Catch defr-warning rather than warning. * lib.c (defr_warning_s): New symbol variable defined. (obj_init): Initialize defr_warning_s. * lib.h (defr_warning_s): Declared. * share/txr/stdlib/error.tl (compile-defr-warning): Throw new-style deferrable warning. * unwind.c (uw_muffle_deferrable_warning): Function removed. (uw_throw): Bugfix: handle warnings by checking by subtype rather than exactly for the warning type. Distinguish deferrable warnings by subtype rather than argument list shape. (uw_defer_warning): Take the new style args and reconstruct the (msg . tag) representation for a deferred warning, so the other functions don't have to change. (uw_late_init): Register defr-warning as exception subtype of warning. * unwind.h (uw_muffle_deferrable_warning): Decl removed. * txr.1: Adjusted all documentation touching on the subject of the representation of deferrable warnings.
* Better way for releasing deferred warnings.Kaz Kylheku2017-02-101-0/+22
| | | | | | | | | | | | | | | | | | | | We should be re-throwing deferred warnings as ordinary warnings, not dumping them to a stream. * eval.c (eval_exception): Use uw_release_deferred_warnings instead of uw_dupm_deferred_warnings. (load): Likewise. * parser.c (read_eval_ret_last): Likewise. * txr.c (txr_main): Likewise. * unwind.c (uw_release_deferred_warnings): New function. * unwind.h (uw_release_deferred_warnings): Declared. * txr.1: Documented release-deferred-warnings and updated documentation for dump-deferred-warnings.
* Muffle only deferrable warnings in sys:expand.Kaz Kylheku2017-02-091-0/+8
| | | | | | | | | | | | | | | | | The problem is that if some macrology is performing its own expansion with sys:expand, and if all warnings are muffled in sys:expand, it means that some warnings will never be seen. Expansion is the last chance to produce warnings issued by macros. Once they are expanded, a redundant expansion pass won't issue the warnings any more. * eval.c (no_warn_expand); Use the uw_muffle_deferrable_warning handler isntead of uw_muffle_warnings. * unwind.c (uw_muffle_deferrable_warning): New function. * unwind.h (uw_muffle_deferrable_warning): Declared.
* Expose defer-warning and dump-deferred-warnings.Kaz Kylheku2017-01-261-0/+2
| | | | | | | * unwind.c (uw_late_init): Register defer-warning and dump-deferred-warnings intrinsics. * txr.1: Documented.
* Registering tentative def must purge warning.Kaz Kylheku2017-01-251-0/+1
| | | | | | | | * match.c (match_reg_var): No need to call uw_purge_deferred_warning here any more. * unwind.c (uw_register_tentative_def): Purge any deferred warnings for the tag.
* Bump copyright year to 2017.Kaz Kylheku2017-01-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | * LICENSE, LICENSE-CYG, METALICENSE, Makefile, args.c, args.h, arith.c, arith.h, cadr.c, cadr.h, combi.c, combi.h, configure, debug.c, debug.h, eval.c, eval.h, filter.c, filter.h, ftw.c, ftw.h, gc.c, gc.h, glob.c, glob.h, hash.c, hash.h, jmp.S, lib.c, lib.h, lisplib.c, lisplib.h, match.c, match.h, parser.c, parser.h, parser.l, parser.y, rand.c, rand.h, regex.c, regex.h, signal.c, signal.h, stream.c, stream.h, struct.c, struct.h, sysif.c, sysif.h, syslog.c, syslog.h, termios.c, termios.h, txr.1, txr.c, txr.h, unwind.c, unwind.h, utf8.c, utf8.h, share/txr/stdlib/awk.tl, share/txr/stdlib/build.tl, share/txr/stdlib/cadr.tl, share/txr/stdlib/conv.tl, share/txr/stdlib/except.tl, share/txr/stdlib/getopts.tl, share/txr/stdlib/getput.tl, share/txr/stdlib/hash.tl, share/txr/stdlib/ifa.tl, share/txr/stdlib/package.tl, share/txr/stdlib/path-test.tl, share/txr/stdlib/place.tl, share/txr/stdlib/socket.tl, share/txr/stdlib/struct.tl, share/txr/stdlib/tagbody.tl, share/txr/stdlib/termios.tl, share/txr/stdlib/txr-case.tl, share/txr/stdlib/type.tl, share/txr/stdlib/with-resources.tl, share/txr/stdlib/with-stream.tl, share/txr/stdlib/yield.tl: Add 2017 to all copyright headers and strings.
* Extend deferred warnings system with tentative defs.Kaz Kylheku2017-01-151-3/+19
| | | | | | | | | | | | | | | | | | | | Tentative defs record the fact that some definition has been seen at expansion time, even though that definition has not been put into effect. They suppress warnings. * unwind.c (tentative_defs): New static variable. (uw_defer_warning): Throw away the warning if it matches a tentative def. (uw_register_tentative_def, uw_tentative_def_exists): New functions. (uw_dump_deferred_warnings): Purge the tag from the list of deferred defs also. (uw_init): gc-protect tentative_defs. Register intrinsics register-tentative-def and tentative-def-exists. * unwind.h (uw_register_tentative_def, uw_tentative_def_exists): Declared.
* Functions for error reporting out of macros.Kaz Kylheku2017-01-151-0/+2
| | | | | | | | | | | | | | | | | * eval.c (eval_init): Register sys:ctx-form and sys:ctx-name intrinsics. * lisplib.c (error_set_entries, error_instantiate): New static functions. (lisplib_init): Register autoloading of error.tl via new functions. * share/txr/stdlib/error.tl: New file. * struct.c (make_struct_type): Purge deferred warnings. * unwind.c (uw_late_init): Register purge-deferred-warning intrinsic.
* Deferred warnings.Kaz Kylheku2017-01-131-2/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Warnings about undefined functions and variables are now deferred during loading, so forward references do not generate nuisance diagnostics. * eval.c (load_recursive_s): New symbol variable. (eval_defr_warn): New static function. (op_defvarl, op_defun): Purge any deferred warning about the given function or variable not being defined. (load): Rebind the sys:*load-recursive* special var to true around the load. After the load, dump deferred warnings if the prior binding of sys:*load-recursive* is false. Discard deferred warnings in the case of termination by a nonlocal control transfer. (do_expand): Treat unbound vars and functions as deferrable warnings, specially tagged for individual purging frkm the deferred list. (eval_init): Intern sys:*load-recursive* and initialize load_recursive_s variable. * eval.h (load_recursive_s): Declared. * parse.c (repl_warning): Accept variable arguments. Check whether we are loading and if so, defer deferrable (repl): Adjustment for altered signature of repl_warning. warnings. * txr.c (txr_main): dump deferred warnings after evaluating Lisp stream. * unwind.c (deferred_warnings): New static variable. (uw_throw): When a deferrable warning is caught, suppress the usual message and add it to the deferred_warnings list. (uw_defer_warning, uw_dump_deferred_warnings, uw_dump_deferred_warnings, uw_purge_deferred_warnings): New functions. (uw_late_init): gc-protect deferred_warnings. * unwind.h (uw_defer_warning, uw_dump_deferred_warnings, uw_dump_deferred_warnings, uw_purge_deferred_warnings): New functions declared.
* New function: find-frames.Kaz Kylheku2016-12-201-3/+17
| | | | | | | | | | | | | * unwind.c (uw_find_frames_impl): New static function, made from uw_find_frame. (uw_find_frame): Reduced to wrapper around uw_find_frames_impl. (uw_find_frames): New function. (uw_late_init): Register find-frames intrinsic. * unwind.h (uw_find_frames): Declared. * txr.1: Documented.
* Eliminate duplicated warning-suppressing function.Kaz Kylheku2016-11-281-0/+7
| | | | | | | | | | | | | | * eval.c (warning_continue): Static function removed. (no_warn_expand): Use uw_muffle_warning instead of removed function. * parser.y (warning_continue): Static function removed. (parse_once): Use uw_muffle_warning instead of removed function. * unwind.c (uw_muffle_warning): New function. * unwind.h (uw_muffle_warning): Declared.
* New function to access exception subtype map.Kaz Kylheku2016-11-261-0/+6
| | | | | | | | | | * uwind.c (exception_subtype_map): New static function. (uw_late_init): Register exception-subtype-map intrinsic function. * txr.1: Exception types are described in more detail. A complete diagram of the existing hierarchyis given, and the exception-subtype-map funtion is documented.
* Expander warns about unbound variables.Kaz Kylheku2016-11-261-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * eval.c (eval_exception): New static function. (eval_error): Reduced to wrapper around eval_exception. (eval_warn): New function. (me_op): Bind the rest symbol in a shadowing env to suppress watnings about unbound rest. (do_expand): Throw a warning when a bindable symbol is traversed that has no binding. (expand): Don't install atoms as last_form_expanded. * lib.c (warning_s, restart_s, continue_s): New symbol variables. (obj_init): Initialize new symbol variables. * lib.h (warning_s, restart_s, continue_s): Declared. * lisplib.c (except_set_entries): New entries for ignwarn and macro-time-ignwarn. * parser.c (repl_warning): New static function. (repl): Use repl_warning function as a handler for warning exceptions: to print their message and then continue by throwing a continue exception. * parser.y (warning_continue): New static function. (parse_once): Use warning_continue to ignore warnings. In other words, we suppress warnings from Lisp that is mixed into TXR pattern language code, because this produces too many false positives. * share/txr/stdlib/except.tl (ignwarn, macro-time-ignwarn): New macros. * share/txr/stdlib/place.tl (call-update-expander, call-clobber-expander, call-delete-expander): Ignore warnings around calls to sys:expand, because of some gensym-related false positives (we expand code into which we inserted some gensyms, without having inserted the constructs which bind them. * tests/011/macros-2.txr: Suppress unbound variable warnings from a test case. * tests/012/ifa.tl: Bind unbound x y variables in one test case. * tests/012/struct.tl: Suppress unbound variable warnings in some test cases. * uwind.c (uw_throw): If a warning is unhandled, then print its message with a "warning" prefix and then throw a continue exception. (uw_register_subtype): Eliminate the check for sub already being a subtype of sup. This allows us to officially register new types against t. (uw_late_init): Register continue exception type as a subtype of the restart type. Formally register warning type. * txr.1: Documented ignwarn.
* Move unwind intrinsics from eval.c to unwind.c.Kaz Kylheku2016-11-231-0/+26
| | | | | | | | | | | | | | | | * eval.c (reg_mac): Static function changed to extern. (me_defex, register_exception_subtypes): Static function removed here; relocated into unwind.c. (eval_init): Registrations of defex, throw, throwf, error, register-exception-subtypes and exception-subtype-p removed. * eval.h (reg_mac): Declared. * unwind.c (me_defex, register_exception_subtypes): Static function moved here. (uw_late_init): Registrations of defex, throw, throwf, error, register-exception-subtypes and exception-subtype-p moved here.
* Flush *stdout* upon unhandled exception.Kaz Kylheku2016-10-311-0/+1
| | | | | | | | * unwind.c (uw_unwind_to_exit_point): Prior to printing diagnostics related to an unhandled exception to std_error, flush std_output. This clarifies the output in situations when both std_error and std_output go to the same destination, and the exception occurred while producing output on std_output.
* Let guard frames optionally pass through unwinding.Kaz Kylheku2016-10-261-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | We have a bug in that when an exception occurs in a context called from obj_print, the guard for stopping continuation captures across obj_print also unintentially blocks the unwinding. Let's make the unwinding blockage optional * unwind.c (uw_unwind_to_exit_point): If a UW_GUARD is encountered, do not abort if the uw_ok flag is set; keep unwinding. (uw_push_guard): New uw_ok argument, initializes the uw_ok member of a guard frame. * unwind.h (struct uw_guard): New struct type. (union uw_frame): New member gu of type struct uw_guard. (uw_push_guard): Declaration updated. * ftw.c (ftw_callback): Pass zero as new uw_push_guard argument: no unwinding across the POSIX library function ftw. * glob.c (errfunc_thunk): Likewise, no unwinding across the library function glob. * lib.c (obj_print): Pass 1 as new uw_push_guard argument: continuations can't be captured, but unwinding is okay.
* nuke trailing newlines from exception messages.Kaz Kylheku2016-10-071-1/+1
| | | | | | | | | * signal.c (set_signal_handler, get_sign_handler): Eliminate newline in exception messages. * stream.c (unimpl, formatv): Likewise. * unwind.c (uw_block_abscond): Likewise.
* Synchronize license comments with LICENSE.Kaz Kylheku2016-10-011-16/+17
| | | | | | | | | | | | | | | | | | | | * Makefile, args.c, args.h, arith.c, arith.h, cadr.c, cadr.h, combi.c, combi.h, configure, debug.c, debug.h, eval.c, eval.h, filter.c, filter.h, ftw.c, ftw.h, gc.c, gc.h, glob.c, glob.h, hash.c, hash.h, jmp.S, lib.c, lib.h, lisplib.c, lisplib.h, match.c, match.h, parser.c, parser.h, parser.l, parser.y, rand.c, rand.h, regex.c, regex.h, share/txr/stdlib/awk.tl, share/txr/stdlib/build.tl, share/txr/stdlib/cadr.tl, share/txr/stdlib/conv.tl, share/txr/stdlib/except.tl, share/txr/stdlib/hash.tl, share/txr/stdlib/ifa.tl, share/txr/stdlib/path-test.tl, share/txr/stdlib/place.tl, share/txr/stdlib/socket.tl, share/txr/stdlib/struct.tl, share/txr/stdlib/termios.tl, share/txr/stdlib/txr-case.tl, share/txr/stdlib/type.tl, share/txr/stdlib/with-resources.tl, share/txr/stdlib/with-stream.tl, share/txr/stdlib/yield.tl, signal.c, signal.h, socket.c, socket.h, stream.c, stream.h, struct.c, struct.h, sysif.c, sysif.h, syslog.c, syslog.h, termios.c, termios.h, txr.1, txr.c, txr.h, unwind.c, unwind.h, utf8.c, utf8.h: Revert to verbatim 2-Clause BSD.
* Adding panic macro, which throws a panic exception.Kaz Kylheku2016-05-071-0/+1
| | | | | | | | | | | * lib.c (panic_s): New symbol variable. (obj_init): Initialize panic_s. * lib.h (panic_s): Declared. * unwind.c (uw_init): Register panic exception. * unwind.h (panic): New macro.
* Valgrind support in continuations.Kaz Kylheku2016-04-161-1/+18
| | | | | | | * unwind.c (revive_cont): When scanning the stack of the revived continuation to fix up pointers, we can save the Valgrind validity bits of each word, mark it defined, and then restore the validity bits.
* Block absconds across foreign frames.Kaz Kylheku2016-04-161-0/+4
| | | | | * unwind.c (uw_block_abscond): If a UW_GUARD frame occurs in the search for the abscond point, throw an error.
* Remove frame popping action from uw_continue.Kaz Kylheku2016-04-111-2/+1
| | | | | | | | | | | | * unwind.c (uw_continue): Don't take the current frame as an argument and consequently don't pop the current frame. This function currently has only one use, the uw_catch_end macro. * unwind.h (uw_continue): Declaration updated. (uw_catch_end): Slight code rearrangement: pop the frame unconditionally before the test for whether uw_continue must be called.
* Typo in comment.Kaz Kylheku2016-04-111-1/+1
| | | | | * unwind.c (uw_unwind_to_exit_point): Misspelled "execute".
* New frame type to block bad unwinding and cont capture.Kaz Kylheku2016-04-081-3/+30
| | | | | | | | | | | | | | | | | | If some external function is invoked which can call back into TXR Lisp, we should guard against the called-back code from capturing a continuation across the external stack frames, and also from unwinding across those frames. This patch prepares a mechanism for this. * unwind.c (uw_unwind_to_exit_point): Abort with message on standard error if attempt is made to unwind across UW_GUARD frame. (uw_push_guard): New function. (uw_capture_cont): If the frame search encounters a UW_GUARD block, an exception is thrown. * unwind.h (enum uw_frtype): New enum constant, UW_GUARD. (uw_push_guard): Declared.
* Implement socket timeouts.Kaz Kylheku2016-03-151-0/+1
| | | | | | | | | | | | | | | | | * lib.c (timeout_error_s): New symbol variable. (obj_init): Intern timeout-error, init new variable. * lib.h (timeout_error_s): Declared. * socket.c (sock_timeout, sock_send_timeout, sock_recv_timeout): New static functions. (sock_load_init): Register sock-send-timeout and sock-recv-timeout intrinsics. * stream.c (stdio_maybe_read_error, stdio_maybe_error): Convert EAGAIN into timeout_error_s. * txr.1: Documented.
* Semantics fix: unhandled exceptions must still unwind.Kaz Kylheku2016-01-221-23/+27
| | | | | | | | | | | | | | | | | * unwind.c (unhandled_ex): New static structure. (unwind_to_exit_point): The code to print the unhandled exception info and bail the process is moved here out of uw_throw. We do this in the situation when we have an unhandled exception, which is represented by the fact that the exception pointer points to the unhandled_ex structure. (uw_throw): If unhandled hook isn't a function, we don't abort; we go through the unwinding and unhandled processing. Also, ditto if the unhandled function returns, ditto. Unhandled processing is entered by substituting unhandled_ex for the not-found exception, and allowing unwind_to_exit point to be called. * txr.1: Document new behavior for unhandled exceptions and *unhandled-hook*.
* Header file cleanup.Kaz Kylheku2016-01-221-1/+0
| | | | | | | * arith.c, cadr.c, debug.c, eval.c, filter.c, gencadr.txr, glob.c, hash.c, linenoise/linenoise.c, lisplib.c, match.c, parser.c, rand.c, regex.c, signal.c, stream.c, struct.c, sysif.c, syslog.c, txr.c, unwind.c, utf8.c: Remove unncessary header files.
* Copyright year bump.Kaz Kylheku2015-12-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | * LICENSE, METALICENSE, Makefile, args.c, args.h, arith.c, arith.h, cadr.c, cadr.h, combi.c, combi.h, configure, debug.c, debug.h, eval.c, eval.h, filter.c, filter.h, gc.c, gc.h, glob.c, glob.h, hash.c, hash.h, jmp.S, lib.c, lib.h, lisplib.c, lisplib.h, match.c, match.h, parser.c, parser.h, parser.l, parser.y, rand.c, rand.h, regex.c, regex.h, share/txr/stdlib/cadr.tl, share/txr/stdlib/except.tl, share/txr/stdlib/hash.tl, share/txr/stdlib/ifa.tl, share/txr/stdlib/path-test.tl, share/txr/stdlib/place.tl, share/txr/stdlib/struct.tl, share/txr/stdlib/txr-case.tl, share/txr/stdlib/type.tl, share/txr/stdlib/with-resources.tl, share/txr/stdlib/with-stream.tl, share/txr/stdlib/yield.tl, signal.c, signal.h, stream.c, stream.h, struct.c, struct.h, sysif.c, sysif.h, syslog.c, syslog.h, txr.1, txr.c, txr.h, unwind.c, unwind.h, utf8.c, utf8.h: Add 2016 copyright. * linenoise/LICENSE, linenoise/linenoise.c, linenoise/linenoise.h: Bump one principal author's copyright from 2014 to 2015. The code is based on a snapshot of 2015 upstream work.
* Useful feature: object post-initialization.Kaz Kylheku2015-12-161-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Structs can now have code which executes after an object is initialized, which is useful for doing work like registering objects in global lists and whatever, when those actions need access to the initialized slots of the object. * share/txr/stdlib/struct.tl (defstruct): Handle :posinit syntax, by generating lambda as eighth argument of sys:make-struct call. * struct.c (struct struct_type): New member, postinitfun. (struct_init): Adjust registrations of make_struct_type to account for new parameter. The user visible make-struct-type is registered as having one optional argument, for backward compat. (make_struct_type): New argument, postinitfun. Store this in the structure. For backward compatibility, the argument is defaulted. (struct_type_mark): Mark the new postinitfun member. (call_postinitfun_chain): New static function. (make_struct, lazy_struct_init): Call call_postinitfun_chain after slots are initialized, and after the boa function is called. * struct.h (make_struct_type): Declaration updated. * lib.c (time_init): Pass eighth argument to make_struct type. * sysif.c (sysif_init): Likewise. * unwind.c (uw_late_init): Likewise. * tests/012/struct.tl: Update defstruct expansion test case. * txr.1: Document new argument of make-struct-type, and clarify ordering of initfun with regard to other actions. Likewise, document :postinit, and clarify ordering of :init actions with regard to other actions.
* Error reports trace through layers of macroexpansion.Kaz Kylheku2015-11-281-26/+4
| | | | | | | | | | | | | | | | | | | | * eval.c (error_trace): New function. Consolidates error reporting between unhandled exception handling in uw_throw, and the catcher in the repl. (op_defmacro, expand_macrolet): Propagate location info from body to wrapping block, and to the macro binding. In the latter function, also to the body that is wrapped by local macros. (do_expand, macroexpand_1): Propagate location info from macro expander to expansion, only taking it from the form if the macro doesn't supply it. * eval.h (error_trace): Declared. * parser.c (repl): Replace error reporting code with call to error_trace. * unwind.c (uw_throw): uw_throw: likewise.
* Report chain of macro-expansions in errors.Kaz Kylheku2015-11-251-1/+9
| | | | | | | | | | | | | | | * eval.c (origin_hash): New global variable. (lookup_origin): New function. (expand_macro): Enter original form into origin hash, keyed by new form. (eval_init): gc-protect and initialize origin_hash. * eval.h (lookup_origin): Declared. * parser.c (repl): Report chain of expansions from last_form_evaled. * unwind.c (uw_throw): Likewise.
* Clear stack area below revived continuation.Kaz Kylheku2015-11-051-0/+1
| | | | | | | | | | | * unwind.c (revive_cont): Don't just reserve frame_slack bytes below the continuation for any stack frame, but clear the bytes to zero. On Cygwin, this fixes a failing continuation test case. The issue is that the cont_obj variable in capture_cont lands into this area (implying it is not captured). When the continuation is revived, the variable has a garbage value, rather than nil, as expected.
* Copy envs for middle-of-binding continuations.Kaz Kylheku2015-11-051-1/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When continuations are captured/restored in the middle of variable binding constructs, a hidden problem occurs. Binding constructs work by allocating an empty environment and then destructively extending it. Since the environment is not on the stack, but a referenced object, it doesn't get deep copied into a continuation. As the continuation is revived repeatedly, parts of the variable binding code are repeatedly re-executed, and keep pushing fresh bindings into the same environment object. Though the new bindings correctly shadow the old, the old bindings are there and potentially hang on to garbage. The solution taken here is to introduce a new kind of frame for handling the situation: a continuation copy handling frame. This frame allows functions to register objects to be copied more deeply if a continuation is captured/revived across them. * eval.c (copy_env): New static function. (copy_env_handler): New static function. (bind_args, bind_macro_params): Install continuation copy handling frame for cloning new_env. (struct bindings_helper_vars): New struct type. (copy_bh_env_handler): New static function. (bindings_helper): Install continuation copy handling frame for de and ne variables which hold environments. The variables are moved to a struct to facilitate access from the handler. * eval.h (copy_env): Declared. * unwind.c (uw_push_cont_copy): New function. (call_copy_handler): New static function. (revive_cont): When a continuation is being revived invoke the copying actions in its continuation copy handling frames, but not if it is only being temporarily revived for immediate unwinding. (capture_cont): After copying the continuation, invoke any continuation copying frames in the "parent": the original frames that were captured. * unwind.h (enum uw_frtype): New type, UW_CONT_COPY. (struct uw_cont_copy): New struct type. (union uw_frame): New member cp. (uw_push_cont_copy): Declared.
* Moving sys:capture-cont to call/cc style API.Kaz Kylheku2015-11-021-7/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | * unwind.c (revive_cont): Don't wrap cons cell around passed arg; just pass it directly. We don't need that convention any more. * capture_cont: Take functional argument. Pass the captured continuation to the function. If the function returns, return whatever it returned. When resuming, return the continuation argument. (uw_capture_cont): Take functional second argument and pass to capture_cont. Context form becomes third argument. (uw_late_init): Update registration of sys:capture-cont to three arguments, two required. * unwind.h (uw_capture_cont): Declaration updated. * share/txr/stdlib/yield.tl (sys:yield-impl): Not needed any more; all this was doing was implementing a call/cc style interface around sys:capture-cont which can now be used directly. (yield-from): Use sys:capture-cont directly. (suspend): Simplified to the point of triviality with new sys:capture-cont. * txr.1: Documented.
* Provide a way to free the continuation stacks.Kaz Kylheku2015-10-291-39/+50
| | | | | | | | | | | | | | | | | | * share/txr/stdlib/yield.tl (sys:obtain-impl): Pass sys:cont-free symbol to each abandoned continuation to release its stack buffer. (obtain): Handle the sys:cont-free symbol in the lambda, so the initial lambda can be treated uniformly with continuation functions. * txr.1: Documented sys:obtain-impl. * unwind.c (sys_cont_free_s): New symbol variable. (cont_mark): Check for null stack pointer and avoid marking. (revive_cont): If arg is sys:cont-free, then free the continuation and return nil. If the continuation has a null stack buffer, throw an error. (uw_late_init): Initialize sys_cont_free_s.
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