install: Don't allow installation over the install files

Author: brson

mk/dist.mk

@@ -199,10 +199,9 @@ dist-install-dir-$(1): PREPARE_LIB_CMD=$(DEFAULT_PREPARE_LIB_CMD)
 dist-install-dir-$(1): PREPARE_MAN_CMD=$(DEFAULT_PREPARE_MAN_CMD)
 dist-install-dir-$(1): PREPARE_CLEAN=true
 dist-install-dir-$(1): prepare-base-dir-$(1)
-# Write the install manifest, making sure the manifest contains itself
-	$$(Q)touch $$(PREPARE_DEST_DIR)/$$(CFG_LIBDIR_RELATIVE)/rustlib/manifest-$(1).in
 	$$(Q)(cd $$(PREPARE_DEST_DIR)/ && find -type f | sed 's/^\.\///') \
-      > $$(PREPARE_DEST_DIR)/$$(CFG_LIBDIR_RELATIVE)/rustlib/manifest-$(1).in
+      > tmp/dist/manifest-$(1).in
+	$$(Q)mv tmp/dist/manifest-$(1).in $$(PREPARE_DEST_DIR)/$$(CFG_LIBDIR_RELATIVE)/rustlib/manifest.in
 # Add remaining non-installed files
 	$$(Q)$$(PREPARE_MAN_CMD) $$(S)COPYRIGHT $$(PREPARE_DEST_DIR)
 	$$(Q)$$(PREPARE_MAN_CMD) $$(S)LICENSE-APACHE $$(PREPARE_DEST_DIR)

src/etc/install.sh

@@ -227,17 +227,29 @@ fi
 step_msg "validating $CFG_SELF args"
 validate_opt
 
+
+# OK, let's get installing ...
+
 # Sanity check: can we can write to the destination?
 umask 022 && mkdir -p "${CFG_LIBDIR}"
-need_ok "can't write to destination. consider `sudo`."
+need_ok "can't write to destination. consider 'sudo'."
 touch "${CFG_LIBDIR}/rust-install-probe" 2> /dev/null
 if [ $? -ne 0 ]
 then
-    err "can't write to destination. consider `sudo`."
+    err "can't write to destination. consider 'sudo'."
 fi
 rm "${CFG_LIBDIR}/rust-install-probe"
 need_ok "failed to remove install probe"
 
+# Sanity check: don't install to the directory containing the installer.
+# That would surely cause chaos.
+INSTALLER_DIR="$(cd $(dirname $0) && pwd)"
+PREFIX_DIR="$(cd ${CFG_PREFIX} && pwd)"
+if [ "${INSTALLER_DIR}" = "${PREFIX_DIR}" ]
+then
+    err "can't install to same directory as installer"
+fi
+
 # The file name of the manifest we're going to create during install
 INSTALLED_MANIFEST="${CFG_LIBDIR}/rustlib/manifest"