Mercurial > gnulib
view lib/safe-read.c @ 39326:c82e97c04ab4
sys-limits.h: new file for crypto and safe I/O
* lib/af_alg.c: Include sys-limits.h.
(MAX_RW_COUNT): Remove. Use replaced by SYS_BUFSIZE_MAX.
(afalg_stream): Also reject negative sizes for sendfile; they
should not happen and the code is a bit cleaner and faster this way.
* lib/safe-read.c: Include sys-limits.h.
(BUGGY_READ_MAXIMUM): Remove. All uses replaced by SYS_BUFSIZE_MAX.
* lib/sys-limits.h: New file, with values and commentary derived
from the old safe-read.c and from GNU Emacs sysdep.c.
* modules/crypto/md5, modules/crypto/sha1, modules/crypto/sha256:
* modules/crypto/sha512, modules/safe-read, modules/safe-write:
Add lib/sys-limits.h to Files section.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Sat, 05 May 2018 10:27:38 -0700 |
parents | 24e347e0e326 |
children | b06060465f09 |
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/* An interface to read and write that retries after interrupts. Copyright (C) 1993-1994, 1998, 2002-2006, 2009-2018 Free Software Foundation, Inc. This program 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. This program 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 this program. If not, see <https://www.gnu.org/licenses/>. */ #include <config.h> /* Specification. */ #ifdef SAFE_WRITE # include "safe-write.h" #else # include "safe-read.h" #endif /* Get ssize_t. */ #include <sys/types.h> #include <unistd.h> #include <errno.h> #ifdef EINTR # define IS_EINTR(x) ((x) == EINTR) #else # define IS_EINTR(x) 0 #endif #include "sys-limits.h" #ifdef SAFE_WRITE # define safe_rw safe_write # define rw write #else # define safe_rw safe_read # define rw read # undef const # define const /* empty */ #endif /* Read(write) up to COUNT bytes at BUF from(to) descriptor FD, retrying if interrupted. Return the actual number of bytes read(written), zero for EOF, or SAFE_READ_ERROR(SAFE_WRITE_ERROR) upon error. */ size_t safe_rw (int fd, void const *buf, size_t count) { for (;;) { ssize_t result = rw (fd, buf, count); if (0 <= result) return result; else if (IS_EINTR (errno)) continue; else if (errno == EINVAL && SYS_BUFSIZE_MAX < count) count = SYS_BUFSIZE_MAX; else return result; } }