From 6c20c8ed2cb9ab69a1a57ccb2b9b79969a808321 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:38:56 +0200 Subject: Adding upstream version 5.2.15. Signed-off-by: Daniel Baumann --- lib/sh/input_avail.c | 165 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 165 insertions(+) create mode 100644 lib/sh/input_avail.c (limited to 'lib/sh/input_avail.c') diff --git a/lib/sh/input_avail.c b/lib/sh/input_avail.c new file mode 100644 index 0000000..2ac4461 --- /dev/null +++ b/lib/sh/input_avail.c @@ -0,0 +1,165 @@ +/* input_avail.c -- check whether or not data is available for reading on a + specified file descriptor. */ + +/* Copyright (C) 2008,2009-2019 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 . +*/ + +#if defined (__TANDEM) +# include +#endif + +#if defined (HAVE_CONFIG_H) +# include +#endif + +#include +#include +#if defined (HAVE_SYS_FILE_H) +# include +#endif /* HAVE_SYS_FILE_H */ + +#if defined (HAVE_PSELECT) +# include +#endif + +#if defined (HAVE_UNISTD_H) +# include +#endif /* HAVE_UNISTD_H */ + +#include "bashansi.h" + +#include "posixselect.h" + +#if defined (FIONREAD_IN_SYS_IOCTL) +# include +#endif + +#include +#include + +#if !defined (errno) +extern int errno; +#endif /* !errno */ + +#if !defined (O_NDELAY) && defined (O_NONBLOCK) +# define O_NDELAY O_NONBLOCK /* Posix style */ +#endif + +/* Return >= 1 if select/FIONREAD indicates data available for reading on + file descriptor FD; 0 if no data available. Return -1 on error. */ +int +input_avail (fd) + int fd; +{ + int result, chars_avail; +#if defined(HAVE_SELECT) + fd_set readfds, exceptfds; + struct timeval timeout; +#endif + + if (fd < 0) + return -1; + + chars_avail = 0; + +#if defined (HAVE_SELECT) + FD_ZERO (&readfds); + FD_ZERO (&exceptfds); + FD_SET (fd, &readfds); + FD_SET (fd, &exceptfds); + timeout.tv_sec = 0; + timeout.tv_usec = 0; + result = select (fd + 1, &readfds, (fd_set *)NULL, &exceptfds, &timeout); + return ((result <= 0) ? 0 : 1); +#endif + +#if defined (FIONREAD) + errno = 0; + result = ioctl (fd, FIONREAD, &chars_avail); + if (result == -1 && errno == EIO) + return -1; + return (chars_avail); +#endif + + return 0; +} + +/* Wait until NCHARS are available for reading on file descriptor FD. + This can wait indefinitely. Return -1 on error. */ +int +nchars_avail (fd, nchars) + int fd; + int nchars; +{ + int result, chars_avail; +#if defined(HAVE_SELECT) + fd_set readfds, exceptfds; +#endif +#if defined (HAVE_PSELECT) || defined (HAVE_SELECT) + sigset_t set, oset; +#endif + + if (fd < 0 || nchars < 0) + return -1; + if (nchars == 0) + return (input_avail (fd)); + + chars_avail = 0; + +#if defined (HAVE_SELECT) + FD_ZERO (&readfds); + FD_ZERO (&exceptfds); + FD_SET (fd, &readfds); + FD_SET (fd, &exceptfds); +#endif +#if defined (HAVE_SELECT) || defined (HAVE_PSELECT) + sigprocmask (SIG_BLOCK, (sigset_t *)NULL, &set); +# ifdef SIGCHLD + sigaddset (&set, SIGCHLD); +# endif + sigemptyset (&oset); +#endif + + while (1) + { + result = 0; +#if defined (HAVE_PSELECT) + /* XXX - use pselect(2) to block SIGCHLD atomically */ + result = pselect (fd + 1, &readfds, (fd_set *)NULL, &exceptfds, (struct timespec *)NULL, &set); +#elif defined (HAVE_SELECT) + sigprocmask (SIG_BLOCK, &set, &oset); + result = select (fd + 1, &readfds, (fd_set *)NULL, &exceptfds, (struct timeval *)NULL); + sigprocmask (SIG_BLOCK, &oset, (sigset_t *)NULL); +#endif + if (result < 0) + return -1; + +#if defined (FIONREAD) + errno = 0; + result = ioctl (fd, FIONREAD, &chars_avail); + if (result == -1 && errno == EIO) + return -1; + if (chars_avail >= nchars) + break; +#else + break; +#endif + } + + return 0; +} -- cgit v1.2.3