[Emacs-diffs] emacs-25 734fb3a: Port dumping to NetBSD with PaX

[Paul Eggert]

branch: emacs-25
commit 734fb3ac6c3e5708ed05b6c5b1d8af92838ee3f5
Author: Paul Eggert <address@hidden>
Commit: Paul Eggert <address@hidden>

    Port dumping to NetBSD with PaX
    
    Problem reported by Thomas Klausner (Bug#23371).
    * configure.ac (PAXCTL_dumped, PAXCTL_notdumped): New vars.
    Set them to setfattr and/or paxctl commands appropriate for
    GNU/Linux and/or NetBSD; the latter prefers paxctl +a.  Search
    for paxctl only if setfattr is not found.
    * src/Makefile.in (PAXCTL_dumped, PAXCTL_notdumped):
    New vars, replacing PAXCTL_if_present and SETFATTR_if_present.
    All uses changed.
---
 configure.ac    |   38 +++++++++++++++++++++++++++++---------
 src/Makefile.in |   18 ++++++++++++------
 2 files changed, 41 insertions(+), 15 deletions(-)

diff --git a/configure.ac b/configure.ac
index 4f169b6..8f8c38b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1140,16 +1140,9 @@ AC_PATH_PROG(GZIP_PROG, gzip)
 test $with_compress_install != yes && test -n "$GZIP_PROG" && \
    GZIP_PROG=" # $GZIP_PROG # (disabled by configure 
--without-compress-install)"
 
+PAXCTL_dumped=
+PAXCTL_notdumped=
 if test $opsys = gnu-linux; then
-  AC_PATH_PROG(PAXCTL, paxctl,,
-    [$PATH$PATH_SEPARATOR/sbin$PATH_SEPARATOR/usr/sbin])
-  if test "X$PAXCTL" != X; then
-    AC_MSG_CHECKING([whether binaries have a PT_PAX_FLAGS header])
-    AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
-      [if $PAXCTL -v conftest$EXEEXT >/dev/null 2>&1; then AC_MSG_RESULT(yes)
-      else AC_MSG_RESULT(no); PAXCTL=""; fi])
-  fi
-
   if test "${SETFATTR+set}" != set; then
     AC_CACHE_CHECK([for setfattr],
       [emacs_cv_prog_setfattr],
@@ -1160,6 +1153,7 @@ if test $opsys = gnu-linux; then
         emacs_cv_prog_setfattr=no
        fi])
     if test "$emacs_cv_prog_setfattr" = yes; then
+      PAXCTL_notdumped='$(SETFATTR) -n user.pax.flags -v er'
       SETFATTR=setfattr
     else
       SETFATTR=
@@ -1168,6 +1162,32 @@ if test $opsys = gnu-linux; then
     AC_SUBST([SETFATTR])
   fi
 fi
+case $opsys,$PAXCTL_notdumped in
+  gnu-linux, | netbsd,)
+    AC_PATH_PROG([PAXCTL], [paxctl], [],
+      [$PATH$PATH_SEPARATOR/sbin$PATH_SEPARATOR/usr/sbin])
+    if test -n "$PAXCTL"; then
+      if test "$opsys" = netbsd; then
+       PAXCTL_dumped='$(PAXCTL) +a'
+       PAXCTL_notdumped=$PAXCTL_dumped
+      else
+       AC_MSG_CHECKING([whether binaries have a PT_PAX_FLAGS header])
+       AC_LINK_IFELSE([AC_LANG_PROGRAM([], [])],
+         [if $PAXCTL -v conftest$EXEEXT >/dev/null 2>&1; then
+            AC_MSG_RESULT([yes])
+          else
+            AC_MSG_RESULT([no])
+            PAXCTL=
+          fi])
+       if test -n "$PAXCTL"; then
+         PAXCTL_dumped='$(PAXCTL) -zex'
+         PAXCTL_notdumped='$(PAXCTL) -r'
+       fi
+      fi
+    fi;;
+esac
+AC_SUBST([PAXCTL_dumped])
+AC_SUBST([PAXCTL_notdumped])
 
 ## Need makeinfo >= 4.7 (?) to build the manuals.
 if test "$MAKEINFO" != "no"; then
diff --git a/src/Makefile.in b/src/Makefile.in
index 1f0df6f..d546709 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -114,8 +114,9 @@ TEMACS_LDFLAGS = $(LD_SWITCH_SYSTEM) 
$(LD_SWITCH_SYSTEM_TEMACS)
 ## around this, newer ones setfattr.  See Bug#11398 and Bug#16343.
 PAXCTL = @PAXCTL@
 SETFATTR = @SETFATTR@
-PAXCTL_if_present = $(or $(PAXCTL),: paxctl)
-SETFATTR_if_present = $(or $(SETFATTR),: setfattr)
+## Commands to set PaX flags on dumped and not-dumped instances of Emacs.
+PAXCTL_dumped = @PAXCTL_dumped@
+PAXCTL_notdumped = @PAXCTL_notdumped@
 
 ## Some systems define this to request special libraries.
 address@hidden@
@@ -532,7 +533,9 @@ ifeq ($(CANNOT_DUMP),yes)
        ln -f temacs$(EXEEXT) $@
 else
        LC_ALL=C $(RUN_TEMACS) -batch -l loadup dump
-       $(PAXCTL_if_present) -zex $@
+  ifneq ($(PAXCTL_dumped),)
+       $(PAXCTL_dumped) $@
+  endif
        ln -f $@ bootstrap-emacs$(EXEEXT)
 endif
 
@@ -594,8 +597,9 @@ temacs$(EXEEXT): $(LIBXMENU) $(ALLOBJS) \
          -o temacs $(ALLOBJS) $(lib)/libgnu.a $(W32_RES_LINK) $(LIBES)
        $(MKDIR_P) $(etc)
 ifneq ($(CANNOT_DUMP),yes)
-       $(PAXCTL_if_present) -r $@
-       $(SETFATTR_if_present) -n user.pax.flags -v er $@
+  ifneq ($(PAXCTL_notdumped),)
+       $(PAXCTL_notdumped) $@
+  endif
 endif
 
 ## The following oldxmenu-related rules are only (possibly) used if
@@ -734,7 +738,9 @@ ifeq ($(CANNOT_DUMP),yes)
        ln -f temacs$(EXEEXT) $@
 else
        $(RUN_TEMACS) --batch --load loadup bootstrap
-       $(PAXCTL_if_present) -zex emacs$(EXEEXT)
+  ifneq ($(PAXCTL_dumped),)
+       $(PAXCTL_dumped) emacs$(EXEEXT)
+  endif
        mv -f emacs$(EXEEXT) $@
 endif
        @: Compile some files earlier to speed up further compilation.