Provide `syscall()` symbol

Provides the `syscall()` function symbol (some language runtimes  link
to the symbol directly). The function is calling `uk_syscall()` when
lib/syscall_shim is enabled. Otherwise, `syscall()` returns always
`-1` and sets `errno` to `ENOSYS`.

Signed-off-by: Simon Kuenzer <simon.kuenzer@neclab.eu>
Reviewed-by: Felipe Huici <felipe.huici@neclab.eu>

diff --git a/Config.uk b/Config.uk
index ab127f0d39e1f754a77dd4e076fbb4c3b35d2a2c..8cb1058d9457a840526815030068c90b4d04e57c 100644 (file)
--- a/Config.uk
+++ b/Config.uk
@@ -13,6 +13,7 @@ menuconfig LIBNEWLIBC
        select LIBVFSCORE
        select LIBPOSIX_PROCESS
        select LIBPOSIX_USER
+       imply LIBSYSCALL_SHIM
 
 if LIBNEWLIBC
        config LIBNEWLIBC_WANT_IO_C99_FORMATS

diff --git a/Makefile.uk b/Makefile.uk
index 390e4f455527b0302d32537c1e24b7a74ef87296..66c3b88cdd4aeb5e6116735b12e8692644ec2d4e 100644 (file)
--- a/Makefile.uk
+++ b/Makefile.uk
@@ -135,6 +135,7 @@ LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/dev.c
 LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/signal.c
 LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/link.c
 LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/mntent.c
+LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/syscall.c
 LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/musl-imported/src/misc/syslog.c
 LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/musl-imported/src/termios/tcsetattr.c
 LIBNEWLIBGLUE_SRCS-y += $(LIBNEWLIBC_BASE)/musl-imported/src/termios/tcgetattr.c

diff --git a/include/sys/syscall.h b/include/sys/syscall.h
index 55ae098d7b92c2ee444611416fab8ce0296dbb0c..18edd7e2d0167f10ab603ec8d023bb69c554ec71 100644 (file)
--- a/include/sys/syscall.h
+++ b/include/sys/syscall.h
@@ -1,6 +1,45 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * Authors: Simon Kuenzer <simon.kuenzer@neclab.eu>
+ *
+ * Copyright (c) 2020, NEC Europe Ltd., NEC Corporation. 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 copyright holder 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.
+ *
+ */
+#ifndef __SYS_SYSCALL_H__
+#define __SYS_SYSCALL_H__
+
 #include <uk/config.h>
+
+long syscall(long num, ...);
+
 #if CONFIG_LIBSYSCALL_SHIM
-#include <uk/syscall.h>
-#else
-#error "Provide alternative syscall.h header"
-#endif
+/* Provide __NR_syscallname variants */
+#include <uk/bits/syscall_nrs2.h>
+#endif /* CONFIG_LIBSYSCALL_SHIM */
+
+#endif /* __SYS_SYSCALL_H__ */

diff --git a/syscall.c b/syscall.c
new file mode 100644 (file)
index 0000000..931cd64
--- /dev/null
+++ b/syscall.c
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * Authors: Simon Kuenzer <simon.kuenzer@neclab.eu>
+ *
+ * Copyright (c) 2020, NEC Europe Ltd., NEC Corporation. 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 copyright holder 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 <uk/config.h>
+#if CONFIG_LIBSYSCALL_SHIM
+#include <stdarg.h>
+#include <uk/syscall.h>
+
+long syscall(long num, ...)
+{
+       va_list va;
+       long arg[6];
+
+       va_start(va, num);
+       arg[0] = va_arg(va, long);
+       arg[1] = va_arg(va, long);
+       arg[2] = va_arg(va, long);
+       arg[3] = va_arg(va, long);
+       arg[4] = va_arg(va, long);
+       arg[5] = va_arg(va, long);
+       va_end(va);
+
+       return uk_syscall(num,
+                         arg[0],
+                         arg[1],
+                         arg[2],
+                         arg[3],
+                         arg[4],
+                         arg[5]);
+}
+
+#else
+#include <errno.h>
+#include <uk/print.h>
+#include <uk/essentials.h>
+
+long syscall(long num __maybe_unused, ...)
+{
+       uk_pr_err("No such system call %lu\n", num);
+       return -ENOSYS;
+}
+#endif /* CONFIG_LIBSYSCALL_SHIM */