1 files changed, 162 insertions, 0 deletions
diff --git a/src/basic/missing_syscalls.py b/src/basic/missing_syscalls.py
new file mode 100644
index 0000000..3749e89
--- /dev/null
+++ b/src/basic/missing_syscalls.py
@@ -0,0 +1,162 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+import sys
+import functools
+
+# We only generate numbers for a dozen or so syscalls
+SYSCALLS = [
+    'bpf',
+    'close_range',
+    'copy_file_range',
+    'fchmodat2',
+    'getrandom',
+    'memfd_create',
+    'mount_setattr',
+    'move_mount',
+    'name_to_handle_at',
+    'open_tree',
+    'openat2',
+    'pidfd_open',
+    'pidfd_send_signal',
+    'pkey_mprotect',
+    'renameat2',
+    'setns',
+    'statx',
+]
+
+def dictify(f):
+    def wrap(*args, **kwargs):
+        return dict(f(*args, **kwargs))
+    return functools.update_wrapper(wrap, f)
+
+@dictify
+def parse_syscall_table(filename):
+    print(f'Reading {filename}…')
+    for line in open(filename):
+        items = line.split()
+        if len(items) >= 2:
+            yield items[0], int(items[1])
+
+def parse_syscall_tables(filenames):
+    return {filename.split('-')[-1][:-4]: parse_syscall_table(filename)
+            for filename in filenames}
+
+DEF_TEMPLATE_A = '''\
+
+#ifndef __IGNORE_{syscall}
+'''
+
+DEF_TEMPLATE_B = '''\
+#  if defined(__aarch64__)
+#    define systemd_NR_{syscall} {nr_arm64}
+#  elif defined(__alpha__)
+#    define systemd_NR_{syscall} {nr_alpha}
+#  elif defined(__arc__) || defined(__tilegx__)
+#    define systemd_NR_{syscall} {nr_arc}
+#  elif defined(__arm__)
+#    define systemd_NR_{syscall} {nr_arm}
+#  elif defined(__i386__)
+#    define systemd_NR_{syscall} {nr_i386}
+#  elif defined(__ia64__)
+#    define systemd_NR_{syscall} {nr_ia64}
+#  elif defined(__loongarch_lp64)
+#    define systemd_NR_{syscall} {nr_loongarch64}
+#  elif defined(__m68k__)
+#    define systemd_NR_{syscall} {nr_m68k}
+#  elif defined(_MIPS_SIM)
+#    if _MIPS_SIM == _MIPS_SIM_ABI32
+#      define systemd_NR_{syscall} {nr_mipso32}
+#    elif _MIPS_SIM == _MIPS_SIM_NABI32
+#      define systemd_NR_{syscall} {nr_mips64n32}
+#    elif _MIPS_SIM == _MIPS_SIM_ABI64
+#      define systemd_NR_{syscall} {nr_mips64}
+#    else
+#      error "Unknown MIPS ABI"
+#    endif
+#  elif defined(__hppa__)
+#    define systemd_NR_{syscall} {nr_parisc}
+#  elif defined(__powerpc__)
+#    define systemd_NR_{syscall} {nr_powerpc}
+#  elif defined(__riscv)
+#    if __riscv_xlen == 32
+#      define systemd_NR_{syscall} {nr_riscv32}
+#    elif __riscv_xlen == 64
+#      define systemd_NR_{syscall} {nr_riscv64}
+#    else
+#      error "Unknown RISC-V ABI"
+#    endif
+#  elif defined(__s390__)
+#    define systemd_NR_{syscall} {nr_s390}
+#  elif defined(__sparc__)
+#    define systemd_NR_{syscall} {nr_sparc}
+#  elif defined(__x86_64__)
+#    if defined(__ILP32__)
+#      define systemd_NR_{syscall} ({nr_x86_64} | /* __X32_SYSCALL_BIT */ 0x40000000)
+#    else
+#      define systemd_NR_{syscall} {nr_x86_64}
+#    endif
+#  elif !defined(missing_arch_template)
+%s
+#  endif
+'''
+
+DEF_TEMPLATE_C = '''\
+
+/* may be an (invalid) negative number due to libseccomp, see PR 13319 */
+#  if defined __NR_{syscall} && __NR_{syscall} >= 0
+#    if defined systemd_NR_{syscall}
+assert_cc(__NR_{syscall} == systemd_NR_{syscall});
+#    endif
+#  else
+#    if defined __NR_{syscall}
+#      undef __NR_{syscall}
+#    endif
+#    if defined systemd_NR_{syscall} && systemd_NR_{syscall} >= 0
+#      define __NR_{syscall} systemd_NR_{syscall}
+#    endif
+#  endif
+#endif'''
+
+DEF_TEMPLATE = (DEF_TEMPLATE_A +
+                DEF_TEMPLATE_B % '#    warning "{syscall}() syscall number is unknown for your architecture"' +
+                DEF_TEMPLATE_C)
+
+ARCH_CHECK = '''\
+/* Note: if this code looks strange, this is because it is derived from the same
+ * template as the per-syscall blocks below. */
+''' + '\n'.join(line for line in DEF_TEMPLATE_B.splitlines()
+                       if ' define ' not in line) % '''\
+#    warning "Current architecture is missing from the template"
+#    define missing_arch_template 1'''
+
+def print_syscall_def(syscall, tables, out):
+    mappings = {f'nr_{arch}':t.get(syscall, -1)
+                for arch, t in tables.items()}
+    print(DEF_TEMPLATE.format(syscall=syscall, **mappings),
+          file=out)
+
+def print_syscall_defs(syscalls, tables, out):
+    print('''\
+/* SPDX-License-Identifier: LGPL-2.1-or-later
+ * This file is generated by src/basic/missing_syscalls.py. Do not edit!
+ *
+ * Use 'ninja -C build update-syscall-tables' to download new syscall tables,
+ * and 'ninja -C build update-syscall-header' to regenerate this file.
+ */
+#pragma once
+''',
+          file=out)
+    print(ARCH_CHECK, file=out)
+    for syscall in syscalls:
+        print_syscall_def(syscall, tables, out)
+
+if __name__ == '__main__':
+    output_file = sys.argv[1]
+    arch_files = sys.argv[2:]
+    out = open(output_file, 'wt')
+
+    tables = parse_syscall_tables(arch_files)
+    print_syscall_defs(SYSCALLS, tables, out)
+
+    print(f'Wrote {output_file}')