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Most of this change is to boilerplate commentary such as license URLs. This change was prompted by ftp://ftp.gnu.org's going-away party, planned for November. Change these FTP URLs to https://ftp.gnu.org instead. Make similar changes for URLs to other organizations moving away from FTP. Also, change HTTP to HTTPS for URLs to gnu.org and fsf.org when this works, as this will further help defend against man-in-the-middle attacks (for this part I omitted the MS-DOS and MS-Windows sources and the test tarballs to keep the workload down). HTTPS is not fully working to lists.gnu.org so I left those URLs alone for now.
72 lines
2.3 KiB
C
72 lines
2.3 KiB
C
/* blockinput.h - interface to blocking complicated interrupt-driven input.
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Copyright (C) 1989, 1993, 2001-2017 Free Software Foundation, Inc.
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This file is part of GNU Emacs.
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GNU Emacs is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or (at
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your option) any later version.
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GNU Emacs is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>. */
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#ifndef EMACS_BLOCKINPUT_H
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#define EMACS_BLOCKINPUT_H
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INLINE_HEADER_BEGIN
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/* Emacs should avoid doing anything hairy in a signal handler, because
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so many system functions are non-reentrant. For example, malloc
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and the Xlib functions aren't usually re-entrant, so if they were
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used by the SIGIO handler, we'd lose.
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To avoid this, we make the following requirements:
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* Everyone must evaluate BLOCK_INPUT before performing actions that
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might conflict with a signal handler, and then call UNBLOCK_INPUT
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after performing them. Calls BLOCK_INPUT and UNBLOCK_INPUT may be
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nested.
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* Any complicated interrupt handling code should test
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INPUT_BLOCKED_P, and put off its work until later.
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* If the interrupt handling code wishes, it may set
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pending_signals to a non-zero value. If that flag is set
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when input becomes unblocked, UNBLOCK_INPUT will then read
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input and process timers.
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Historically, Emacs signal handlers did much more than they do now,
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and this caused many BLOCK_INPUT calls to be sprinkled around the code.
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FIXME: Remove calls that aren't needed now. */
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extern volatile int interrupt_input_blocked;
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/* Begin critical section. */
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INLINE void
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block_input (void)
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{
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interrupt_input_blocked++;
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}
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extern void unblock_input (void);
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extern void totally_unblock_input (void);
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extern void unblock_input_to (int);
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/* In critical section? */
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INLINE bool
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input_blocked_p (void)
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{
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return interrupt_input_blocked > 0;
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}
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INLINE_HEADER_END
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#endif /* EMACS_BLOCKINPUT_H */
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