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Diffstat (limited to 'unwind_prot.c~')
| -rw-r--r-- | unwind_prot.c~ | 357 |
1 files changed, 0 insertions, 357 deletions
diff --git a/unwind_prot.c~ b/unwind_prot.c~ deleted file mode 100644 index a477c03a..00000000 --- a/unwind_prot.c~ +++ /dev/null @@ -1,357 +0,0 @@ -/* unwind_prot.c - a simple unwind-protect system for internal variables */ - -/* I can't stand it anymore! Please can't we just write the - whole Unix system in lisp or something? */ - -/* Copyright (C) 1987-2009 Free Software Foundation, Inc. - - This file is part of GNU Bash, the Bourne Again SHell. - - Bash is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. - - Bash is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with Bash. If not, see <http://www.gnu.org/licenses/>. -*/ - -/* **************************************************************** */ -/* */ -/* Unwind Protection Scheme for Bash */ -/* */ -/* **************************************************************** */ -#include "config.h" - -#include "bashtypes.h" -#include "bashansi.h" - -#if defined (HAVE_UNISTD_H) -# include <unistd.h> -#endif - -#if STDC_HEADERS -# include <stddef.h> -#endif - -#ifndef offsetof -# define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) -#endif - -#include "command.h" -#include "general.h" -#include "unwind_prot.h" -#include "quit.h" -#include "sig.h" -#include "error.h" /* for internal_warning */ - -/* Structure describing a saved variable and the value to restore it to. */ -typedef struct { - char *variable; - int size; - char desired_setting[1]; /* actual size is `size' */ -} SAVED_VAR; - -/* If HEAD.CLEANUP is null, then ARG.V contains a tag to throw back to. - If HEAD.CLEANUP is restore_variable, then SV.V contains the saved - variable. Otherwise, call HEAD.CLEANUP (ARG.V) to clean up. */ -typedef union uwp { - struct uwp_head { - union uwp *next; - Function *cleanup; - } head; - struct { - struct uwp_head uwp_head; - char *v; - } arg; - struct { - struct uwp_head uwp_head; - SAVED_VAR v; - } sv; -} UNWIND_ELT; - - -static void without_interrupts __P((VFunction *, char *, char *)); -static void unwind_frame_discard_internal __P((char *, char *)); -static void unwind_frame_run_internal __P((char *, char *)); -static void add_unwind_protect_internal __P((Function *, char *)); -static void remove_unwind_protect_internal __P((char *, char *)); -static void run_unwind_protects_internal __P((char *, char *)); -static void clear_unwind_protects_internal __P((char *, char *)); -static inline void restore_variable __P((SAVED_VAR *)); -static void unwind_protect_mem_internal __P((char *, char *)); - -static UNWIND_ELT *unwind_protect_list = (UNWIND_ELT *)NULL; - -#define uwpalloc(elt) (elt) = (UNWIND_ELT *)xmalloc (sizeof (UNWIND_ELT)) -#define uwpfree(elt) free(elt) - -/* Run a function without interrupts. This relies on the fact that the - FUNCTION cannot change the value of interrupt_immediately. (I.e., does - not call QUIT (). */ -static void -without_interrupts (function, arg1, arg2) - VFunction *function; - char *arg1, *arg2; -{ - int old_interrupt_immediately; - - old_interrupt_immediately = interrupt_immediately; - interrupt_immediately = 0; - - (*function)(arg1, arg2); - - interrupt_immediately = old_interrupt_immediately; -} - -/* Start the beginning of a region. */ -void -begin_unwind_frame (tag) - char *tag; -{ - add_unwind_protect ((Function *)NULL, tag); -} - -/* Discard the unwind protects back to TAG. */ -void -discard_unwind_frame (tag) - char *tag; -{ - if (unwind_protect_list) - without_interrupts (unwind_frame_discard_internal, tag, (char *)NULL); -} - -/* Run the unwind protects back to TAG. */ -void -run_unwind_frame (tag) - char *tag; -{ - if (unwind_protect_list) - without_interrupts (unwind_frame_run_internal, tag, (char *)NULL); -} - -/* Add the function CLEANUP with ARG to the list of unwindable things. */ -void -add_unwind_protect (cleanup, arg) - Function *cleanup; - char *arg; -{ - without_interrupts (add_unwind_protect_internal, (char *)cleanup, arg); -} - -/* Remove the top unwind protect from the list. */ -void -remove_unwind_protect () -{ - if (unwind_protect_list) - without_interrupts - (remove_unwind_protect_internal, (char *)NULL, (char *)NULL); -} - -/* Run the list of cleanup functions in unwind_protect_list. */ -void -run_unwind_protects () -{ - if (unwind_protect_list) - without_interrupts - (run_unwind_protects_internal, (char *)NULL, (char *)NULL); -} - -/* Erase the unwind-protect list. If flags is 1, free the elements. */ -void -clear_unwind_protect_list (flags) - int flags; -{ - char *flag; - - if (unwind_protect_list) - { - flag = flags ? "" : (char *)NULL; - without_interrupts - (clear_unwind_protects_internal, flag, (char *)NULL); - } -} - -int -have_unwind_protects () -{ - return (unwind_protect_list != 0); -} - -/* **************************************************************** */ -/* */ -/* The Actual Functions */ -/* */ -/* **************************************************************** */ - -static void -add_unwind_protect_internal (cleanup, arg) - Function *cleanup; - char *arg; -{ - UNWIND_ELT *elt; - - uwpalloc (elt); - elt->head.next = unwind_protect_list; - elt->head.cleanup = cleanup; - elt->arg.v = arg; - unwind_protect_list = elt; -} - -static void -remove_unwind_protect_internal (ignore1, ignore2) - char *ignore1, *ignore2; -{ - UNWIND_ELT *elt; - - elt = unwind_protect_list; - if (elt) - { - unwind_protect_list = unwind_protect_list->head.next; - uwpfree (elt); - } -} - -static void -run_unwind_protects_internal (ignore1, ignore2) - char *ignore1, *ignore2; -{ - unwind_frame_run_internal ((char *) NULL, (char *) NULL); -} - -static void -clear_unwind_protects_internal (flag, ignore) - char *flag, *ignore; -{ - if (flag) - { - while (unwind_protect_list) - remove_unwind_protect_internal ((char *)NULL, (char *)NULL); - } - unwind_protect_list = (UNWIND_ELT *)NULL; -} - -static void -unwind_frame_discard_internal (tag, ignore) - char *tag, *ignore; -{ - UNWIND_ELT *elt; - int found; - - found = 0; - while (elt = unwind_protect_list) - { - unwind_protect_list = unwind_protect_list->head.next; - if (elt->head.cleanup == 0 && (STREQ (elt->arg.v, tag))) - { - uwpfree (elt); - found = 1; - break; - } - else - uwpfree (elt); - } - - if (found == 0) - internal_warning ("unwind_frame_discard: %s: frame not found", tag); -} - -/* Restore the value of a variable, based on the contents of SV. - sv->desired_setting is a block of memory SIZE bytes long holding the - value itself. This block of memory is copied back into the variable. */ -static inline void -restore_variable (sv) - SAVED_VAR *sv; -{ - FASTCOPY (sv->desired_setting, sv->variable, sv->size); -} - -static void -unwind_frame_run_internal (tag, ignore) - char *tag, *ignore; -{ - UNWIND_ELT *elt; - int found; - - found = 0; - while (elt = unwind_protect_list) - { - unwind_protect_list = elt->head.next; - - /* If tag, then compare. */ - if (elt->head.cleanup == 0) - { - if (tag && STREQ (elt->arg.v, tag)) - { - uwpfree (elt); - found = 1; - break; - } - } - else - { - if (elt->head.cleanup == (Function *) restore_variable) - restore_variable (&elt->sv.v); - else - (*(elt->head.cleanup)) (elt->arg.v); - } - - uwpfree (elt); - } - if (tag && found == 0) - internal_warning ("unwind_frame_run: %s: frame not found", tag); -} - -static void -unwind_protect_mem_internal (var, psize) - char *var; - char *psize; -{ - int size, allocated; - UNWIND_ELT *elt; - - size = *(int *) psize; - allocated = size + offsetof (UNWIND_ELT, sv.v.desired_setting[0]); - elt = (UNWIND_ELT *)xmalloc (allocated); - elt->head.next = unwind_protect_list; - elt->head.cleanup = (Function *) restore_variable; - elt->sv.v.variable = var; - elt->sv.v.size = size; - FASTCOPY (var, elt->sv.v.desired_setting, size); - unwind_protect_list = elt; -} - -/* Save the value of a variable so it will be restored when unwind-protects - are run. VAR is a pointer to the variable. SIZE is the size in - bytes of VAR. */ -void -unwind_protect_mem (var, size) - char *var; - int size; -{ - without_interrupts (unwind_protect_mem_internal, var, (char *) &size); -} - -#if defined (DEBUG) -#include <stdio.h> - -void -print_unwind_protect_tags () -{ - UNWIND_ELT *elt; - - elt = unwind_protect_list; - while (elt) - { - unwind_protect_list = unwind_protect_list->head.next; - if (elt->head.cleanup == 0) - fprintf(stderr, "tag: %s\n", elt->arg.v); - elt = unwind_protect_list; - } -} -#endif |