Add support for ARC to libgloss

ChangeLog:
2015-11-12  Anton Kolesov  <Anton.Kolesov@synopsys.com>

	* configure.in: Add ARC support to libgloss.
	* configure: Regenerate.

libgloss/ChangeLog:
2015-11-12  Anton Kolesov  <Anton.Kolesov@synopsys.com>

	* configure: Add ARC support.
	* configure.in: Likewise.
	* arc/Makefile.in: Likewise.
	* arc/aclocal.m4: Likewise.
	* arc/configure: Likewise.
	* arc/configure.in: Likewise.
	* arc/crt0.S: Likewise.
	* arc/libcfunc.c: Likewise.
	* arc/nsim-syscall.h: Likewise.
	* arc/nsim-syscalls.c: Likewise.
	* arc/nsim.specs: Likewise.
	* arc/sbrk.c: Likewise.

1 files changed, 235 insertions, 0 deletions

diff --git a/libgloss/arc/nsim-syscalls.c b/libgloss/arc/nsim-syscalls.c
new file mode 100644
index 000000000..7dd0af10f
--- /dev/null
+++ b/libgloss/arc/nsim-syscalls.c
@@ -0,0 +1,235 @@
+/*
+   Copyright (c) 2015, Synopsys, Inc. All rights reserved.
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are met:
+
+   1) Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+
+   2) Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+   3) Neither the name of the Synopsys, Inc., nor the names of its contributors
+   may be used to endorse or promote products derived from this software
+   without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+   POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <_ansi.h>
+#include <_syslist.h>
+#include <errno.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/times.h>
+#include <sys/types.h>
+
+#include "glue.h"
+#include "nsim-syscall.h"
+
+/* Those system calls are implemented in both nSIM and CGEN.  */
+_syscall3 (_ssize_t, read, int, fd, void *, buf, size_t, count)
+_syscall3 (_ssize_t, write, int, fd, const void *, buf, size_t, count)
+_syscall1 (int, unlink, const char *, pathname)
+_syscall3 (off_t, lseek, int, fd, off_t, offset, int, whence)
+_syscall2 (int, gettimeofday, struct timeval *, tv, void *, tz)
+_syscall1 (_CLOCK_T_, time, _CLOCK_T_ *, t)
+_syscall1 (int, close, int, fd)
+_syscall1 (_CLOCK_T_, times, struct tms *, buf)
+/* stat requires custom implementation.  */
+/* _syscall2 (int, stat, const char *, path, struct stat *, st)
+   _syscall2 (int, fstat, int, file, struct stat *, st) */
+/* nSIM implements brk and sbrk, but instead sbrk.c is used.  */
+/* _syscall1 (int, brk, void *, addr) */
+/* open requires custom implementation.  */
+/* _syscall3 (int, open, const char *, pathname, int, flags, int, mode) */
+
+/* Those syscalls are not available in CGEN simulator.  */
+_syscall1 (int, rmdir, const char *, pathname)
+_syscall2 (char *, getcwd, char *, buf, size_t, size)
+/* stat requires custom implementation.  */
+/* _syscall2 (int, lstat, const char *, path, struct stat *, st) */
+
+/* Historically "open" flags defined by default in newlib and in Linux for ARC
+   are different - this is true for some other architectures as well, e.g.
+   ARM.  To provide compatibility ARC port of newlib had a custom fcntl.h file
+   that has "open" flags identical to Linux ones.  Some other architectures
+   (spart64, cris) override default fcntl.h as well, but I'm not sure this is
+   really a good idea.  Unlike system call numbers that can be unique to each
+   BSP in libgloss, "open" flags are not abstracted from the application code
+   itself, hence it is not possible to have fcntl.h in the libgloss.  To make
+   matters worse, existing simulators already has been built for the Linux-like
+   "open" flags.  To preserve compatibility with existing hostlink
+   implementations in simulators, but avoid custom fcntl.h in the future,
+   simulator BSP has to do dynamic rewriting of "open" flags from the newlib
+   default into old ARC Linux flags.  Simulators support only most basic flags,
+   therefore only those are translated in this implementation.  */
+int
+_open (const char * pathname, int flags, int mode)
+{
+  int nsim_flags = 0;
+
+  /* RDONLY, WRONLY, RDWR are same as newlib default.  */
+  nsim_flags |= flags & O_RDONLY;
+  nsim_flags |= flags & O_WRONLY;
+  nsim_flags |= flags & O_RDWR;
+  nsim_flags |= (flags & O_CREAT) ? ARC_LINUX_CREAT : 0;
+  nsim_flags |= (flags & O_APPEND) ? ARC_LINUX_APPEND : 0;
+  nsim_flags |= (flags & O_TRUNC) ? ARC_LINUX_TRUNC : 0;
+  nsim_flags |= (flags & O_EXCL) ? ARC_LINUX_EXCL : 0;
+  /* There are other fcntl flags that are different between newlib and ARC
+     uClibc, however they are not supported by nSIM hostlink, therefore there
+     is no need to translate them.  */
+
+  long __res;
+  _naked_syscall3 (__res, open, pathname, nsim_flags, mode)
+  return __res;
+}
+
+/* Should be provided by crt0.S.  */
+extern void __attribute__((noreturn)) _exit_halt ();
+
+void
+__attribute__((noreturn))
+_exit (int ret)
+{
+  /* Doing an "exit" system call would work on nSIM with hostlink, but call to
+     _exit_halt, which will do a CPU halt is more universal and will work in
+     many other cases as well, including an FPGA/SoC.  */
+  _exit_halt ();
+}
+
+/* This is a copy of newlib/libc/posix/_isatty.c.  It is needed because nSIM
+   hostlink doesn't implement isatty system call.  Hardware boards on the other
+   hand would want isatty implementation that always returns 1, since they are
+   connected to console and doesn't have file IO.  */
+int
+_isatty (int fd)
+{
+  struct stat buf;
+
+  if (fstat (fd, &buf) < 0)
+    {
+      errno = EBADF;
+      return 0;
+    }
+  if (S_ISCHR (buf.st_mode))
+    {
+      return 1;
+    }
+  errno = ENOTTY;
+  return 0;
+}
+
+/* System call "getpid" is implemented in nSIM hostlink, but it is better not
+   to expose it in libgloss.  */
+int
+_getpid (void)
+{
+  return __MYPID;
+}
+
+/* System call "kill" is implemented in nSIM hostlink on Linux hosts, but it
+   seems dangerous to expose it.  Instead, like most of the other "_kill"
+   implementations in libgloss, this will kill only self.  */
+int
+_kill (int pid, int sig)
+{
+  if (pid == __MYPID)
+    {
+      _exit (sig);
+    }
+  errno = ENOSYS;
+  return -1;
+}
+
+static void
+translate_stat (struct nsim_stat *nsim, struct stat *buf)
+{
+  #define TR(field, type) buf->st_ ## field = (type) nsim->field
+  TR (dev, dev_t);
+  TR (ino, ino_t);
+  TR (mode, mode_t);
+  TR (nlink, nlink_t);
+  TR (uid, uid_t);
+  TR (gid, gid_t);
+  TR (rdev, dev_t);
+  TR (size, off_t);
+  TR (atime, time_t);
+  TR (mtime, time_t);
+  TR (ctime, time_t);
+  TR (blksize, long);
+  TR (blocks, long);
+  #undef TR
+}
+
+/* stat/fstat implementation.  Situation is similiar to open and its flags -
+   structure is defined in libc, hence cannot be customized in libgloss, yet we
+   have a case where nSIM uses some definition which is not compatible with
+   neither old ARC-custom definition of "struct stat" in newlib, nor with
+   generic newlib implementation.  */
+int
+_stat (const char * path, struct stat *buf)
+{
+  struct nsim_stat nsim_stat;
+  long __res;
+  _naked_syscall2 (__res, stat, path, &nsim_stat)
+  translate_stat (&nsim_stat, buf);
+  return __res;
+}
+
+int
+_lstat (const char * path, struct stat *buf)
+{
+  struct nsim_stat nsim_stat;
+  long __res;
+  _naked_syscall2 (__res, stat, path, &nsim_stat)
+  translate_stat (&nsim_stat, buf);
+  return __res;
+}
+
+int
+_fstat (int fd, struct stat *buf)
+{
+  struct nsim_stat nsim_stat;
+  long __res;
+  _naked_syscall2 (__res, stat, fd, &nsim_stat)
+  translate_stat (&nsim_stat, buf);
+  return __res;
+}
+
+/* Some system calls are implemented in nSIM hostlink, but are available only
+   on Linux hosts.  To minimize potential compatibility issues they are by
+   default disabled in libgloss build.  */
+#ifdef ARC_NSIM_WIN32_HOST
+_syscall3 (int, ioctl, int, fd, int, request, char *, argp)
+_syscall3 (_ssize_t, readv, int, fd, const struct iovec *, iov, int, iovcnt)
+_syscall3 (_ssize_t, writev, int, fd, const struct iovec *, iov, int, iovcnt)
+_syscall5 (off_t, llseek, int, fd, unsigned long, offset_high,
+	   unsigned long, offset_low, loff_t *, result,
+	   unsigned int, whence)
+_syscall2 (int, getrusage, int, who, struct rusage *, usage)
+_syscall2 (int, setrlimit, int, resource, const struct rlimit *, rlim)
+_syscall2 (int, getrlimit, int, resource, struct rlimit *, rlim)
+_syscall3 (int, sigaction, int signum, const struct sigaction *, act,
+	   struct sigaction *, oldact)
+_syscall0 (uid_t, getuid)
+_syscall0 (gid_t, getgid)
+_syscall0 (uid_t, geteuid)
+_syscall0 (gid_t, getegid)
+_syscall2 (int, kill, pid_t, pid, int, sig)
+_syscall3 (_ssize_t, readlink, const char *, path, char *, buf, size_t, bufsize)
+#endif