Merge branch 'wip/smcv/closefrom' into 'master'

Fixes for g_closefrom() backport

See merge request GNOME/libglnx!54

Author: cgwalters

glnx-backports.c

@@ -36,6 +36,7 @@
 #include "libglnx-config.h"
 
 #include "glnx-backports.h"
+#include "glnx-missing.h"
 
 #include <dirent.h>
 #include <errno.h>

glnx-missing-syscall.h

@@ -32,6 +32,7 @@
 */
 
 #include "libglnx-config.h"
+#include <glib.h>
 
 #if !HAVE_DECL_RENAMEAT2
 #  ifndef __NR_renameat2
@@ -155,3 +156,83 @@ static inline ssize_t missing_copy_file_range(int fd_in, loff_t *off_in,
 
 #  define copy_file_range missing_copy_file_range
 #endif
+
+#ifndef __IGNORE_close_range
+#  if defined(__aarch64__)
+#    define systemd_NR_close_range 436
+#  elif defined(__alpha__)
+#    define systemd_NR_close_range 546
+#  elif defined(__arc__) || defined(__tilegx__)
+#    define systemd_NR_close_range 436
+#  elif defined(__arm__)
+#    define systemd_NR_close_range 436
+#  elif defined(__i386__)
+#    define systemd_NR_close_range 436
+#  elif defined(__ia64__)
+#    define systemd_NR_close_range 1460
+#  elif defined(__loongarch_lp64)
+#    define systemd_NR_close_range 436
+#  elif defined(__m68k__)
+#    define systemd_NR_close_range 436
+#  elif defined(_MIPS_SIM)
+#    if _MIPS_SIM == _MIPS_SIM_ABI32
+#      define systemd_NR_close_range 4436
+#    elif _MIPS_SIM == _MIPS_SIM_NABI32
+#      define systemd_NR_close_range 6436
+#    elif _MIPS_SIM == _MIPS_SIM_ABI64
+#      define systemd_NR_close_range 5436
+#    else
+#      error "Unknown MIPS ABI"
+#    endif
+#  elif defined(__hppa__)
+#    define systemd_NR_close_range 436
+#  elif defined(__powerpc__)
+#    define systemd_NR_close_range 436
+#  elif defined(__riscv)
+#    if __riscv_xlen == 32
+#      define systemd_NR_close_range 436
+#    elif __riscv_xlen == 64
+#      define systemd_NR_close_range 436
+#    else
+#      error "Unknown RISC-V ABI"
+#    endif
+#  elif defined(__s390__)
+#    define systemd_NR_close_range 436
+#  elif defined(__sparc__)
+#    define systemd_NR_close_range 436
+#  elif defined(__x86_64__)
+#    if defined(__ILP32__)
+#      define systemd_NR_close_range (436 | /* __X32_SYSCALL_BIT */ 0x40000000)
+#    else
+#      define systemd_NR_close_range 436
+#    endif
+#  elif !defined(missing_arch_template)
+#    warning "close_range() syscall number is unknown for your architecture"
+#  endif
+
+/* may be an (invalid) negative number due to libseccomp, see PR 13319 */
+#  if defined __NR_close_range && __NR_close_range >= 0
+#    if defined systemd_NR_close_range
+G_STATIC_ASSERT(__NR_close_range == systemd_NR_close_range);
+#    endif
+#  else
+#    if defined __NR_close_range
+#      undef __NR_close_range
+#    endif
+#    if defined systemd_NR_close_range && systemd_NR_close_range >= 0
+#      define __NR_close_range systemd_NR_close_range
+#    endif
+#  endif
+#endif
+
+#if !defined(HAVE_CLOSE_RANGE) && defined(__NR_close_range)
+static inline int
+inline_close_range (unsigned int low,
+                    unsigned int high,
+                    int flags)
+{
+  return syscall (__NR_close_range, low, high, flags);
+}
+#define close_range(low, high, flags) inline_close_range(low, high, flags)
+#define HAVE_CLOSE_RANGE
+#endif

glnx-missing.h

@@ -92,4 +92,12 @@
 #define MFD_CLOEXEC 0x0001U
 #endif
 
+#ifndef CLOSE_RANGE_UNSHARE
+#define CLOSE_RANGE_UNSHARE (1U << 1)
+#endif
+
+#ifndef CLOSE_RANGE_CLOEXEC
+#define CLOSE_RANGE_CLOEXEC (1U << 2)
+#endif
+
 #include "glnx-missing-syscall.h"

libglnx.m4

@@ -4,6 +4,7 @@
 
 AC_DEFUN([LIBGLNX_CONFIGURE],
 [
+dnl This defines HAVE_DECL_FOO to 1 if found or 0 if not
 AC_CHECK_DECLS([
         renameat2,
         memfd_create,
@@ -19,6 +20,9 @@ AC_CHECK_DECLS([
 #include <linux/random.h>
 #include <sys/mman.h>
 ]])
+dnl This defines HAVE_FOO to 1 if found, or leaves it undefined if not:
+dnl not the same!
+AC_CHECK_FUNCS([close_range])
 
 AC_ARG_ENABLE(otmpfile,
               [AS_HELP_STRING([--disable-otmpfile],

meson.build

@@ -49,16 +49,16 @@ foreach check_function : check_functions
   )
   conf.set10('HAVE_DECL_' + check_function.underscorify().to_upper(), have_it)
 endforeach
-config_h = configure_file(
-  output : 'libglnx-config.h',
-  configuration : conf,
-)
 
 check_functions = [
   'close_range',
 ]
 foreach check_function : check_functions
+  if cc.has_function(check_function)
+    conf.set('HAVE_' + check_function.underscorify().to_upper(), 1)
+  endif
 endforeach
+
 config_h = configure_file(
   output : 'libglnx-config.h',
   configuration : conf,