add --force option to write ELF binary without changes

patchelf.1

@@ -143,6 +143,11 @@ Use sparingly and with caution.
 .IP "--output FILE"
 Set the output file name.  If not specified, the input will be modified in place.
 
+.IP --force
+Force write-out of the ELF binary even when no changes were made.
+This is useful for fixing ELF binaries that have issues like
+"Program headers not in the first page".
+
 .IP --debug
 Prints details of the changes made to the input file.
 

src/patchelf.cc

@@ -2564,6 +2564,7 @@ static void showHelp(const std::string & progName)
   [--rename-dynamic-symbols NAME_MAP_FILE]\tRenames dynamic symbols. The map file should contain two symbols (old_name new_name) per line\n\
   [--no-clobber-old-sections]\t\tDo not clobber old section values - only use when the binary expects to find section info at the old location.\n\
   [--output FILE]\n\
+  [--force]\t\tForce write-out even if no changes were made\n\
   [--debug]\n\
   [--version]\n\
   FILENAME...\n", progName.c_str());
@@ -2685,6 +2686,9 @@ static int mainWrapped(int argc, char * * argv)
             outputFileName = resolveArgument(argv[i]);
             alwaysWrite = true;
         }
+        else if (arg == "--force") {
+            alwaysWrite = true;
+        }
         else if (arg == "--debug") {
             debugMode = true;
         }

tests/Makefile.am

@@ -25,6 +25,7 @@ src_TESTS = \
   set-rpath-library.sh soname.sh shrink-rpath-with-allowed-prefixes.sh \
   set-rpath-rel-map.sh \
   force-rpath.sh \
+  force.sh \
   plain-needed.sh \
   output-flag.sh \
   too-many-strtab.sh \

tests/force.sh

@@ -0,0 +1,33 @@
+#! /bin/sh -e
+SCRATCH=scratch/$(basename "$0" .sh)
+
+rm -rf "${SCRATCH}"
+mkdir -p "${SCRATCH}"
+
+cp simple "${SCRATCH}/"
+
+../src/patchelf --force "${SCRATCH}/simple"
+
+exitCode=0
+"${SCRATCH}/simple" || exitCode=$?
+
+if test "$exitCode" != 0; then
+    echo "bad exit code after --force!"
+    exit 1
+fi
+
+cp simple "${SCRATCH}/simple2"
+../src/patchelf --force --output "${SCRATCH}/simple2-out" "${SCRATCH}/simple2"
+
+if ! test -f "${SCRATCH}/simple2-out"; then
+    echo "--force with --output did not create output file!"
+    exit 1
+fi
+
+exitCode=0
+"${SCRATCH}/simple2-out" || exitCode=$?
+
+if test "$exitCode" != 0; then
+    echo "bad exit code after --force --output!"
+    exit 1
+fi