libxbps: pkg remove: never remove base symlinks in the root directory.

The /bin, /sbin, /lib, /lib32, /lib64, /var/run symlinks should never be removed
in Void, so be safe and ignore the removal of them.

Added another test to the testsuite to verify its correctness.

NEWS

@@ -1,5 +1,8 @@
 xbps-0.27 (???):
 
+ * libxbps: make sure that base symlinks in the root directory are never removed,
+   due to /usr switch in Void. This will also be harmless in other systems.
+
  * The testsuite now contains more tests than ever and will be extended as new
    issues appear.
 

lib/package_remove.c

@@ -33,6 +33,21 @@
 
 #include "xbps_api_impl.h"
 
+#ifndef __arraycount
+# define __arraycount(a) (sizeof(a) / sizeof(*(a)))
+#endif
+
+/* These are symlinks in Void and must not be removed */
+static const char *basesymlinks[] = {
+	"/bin",
+	"/sbin",
+	"/lib",
+	"/lib32",
+	"/lib64",
+	"/usr/lib64",
+	"/var/run",
+};
+
 int HIDDEN
 xbps_remove_pkg_files(struct xbps_handle *xhp,
 		      xbps_dictionary_t dict,
@@ -44,9 +59,10 @@ xbps_remove_pkg_files(struct xbps_handle *xhp,
 	xbps_object_iterator_t iter;
 	xbps_object_t obj;
 	const char *file, *sha256, *curobj = NULL;
-	char *path = NULL, *pkgname = NULL;
+	char *path = NULL;
 	char buf[PATH_MAX];
 	int rv = 0;
+	bool found;
 
 	assert(xbps_object_type(dict) == XBPS_TYPE_DICTIONARY);
 	assert(key != NULL);
@@ -68,9 +84,6 @@ xbps_remove_pkg_files(struct xbps_handle *xhp,
 	else if (strcmp(key, "dirs") == 0)
 		curobj = "directory";
 
-	pkgname = xbps_pkg_name(pkgver);
-	assert(pkgname);
-
 	while ((obj = xbps_object_iterator_next(iter))) {
 		xbps_dictionary_get_cstring_nocopy(obj, "file", &file);
 		path = xbps_xasprintf("%s/%s", xhp->rootdir, file);
@@ -141,6 +154,22 @@ xbps_remove_pkg_files(struct xbps_handle *xhp,
 				continue;
 			}
 		}
+		/*
+		 * Make sure to not remove any symlink of root directory.
+		 */
+		found = false;
+		for (uint8_t i = 0; i < __arraycount(basesymlinks); i++) {
+			if (strcmp(file, basesymlinks[i]) == 0) {
+				found = true;
+				xbps_dbg_printf(xhp, "[remove] %s ignoring "
+				    "%s removal\n", pkgver, file);
+				break;
+			}
+		}
+		if (found) {
+			free(path);
+			continue;
+		}
 		/*
 		 * Remove the object if possible.
 		 */
@@ -158,7 +187,6 @@ xbps_remove_pkg_files(struct xbps_handle *xhp,
 		free(path);
 	}
 	xbps_object_iterator_release(iter);
-	free(pkgname);
 
 	return rv;
 }

tests/xbps/libxbps/common/Kyuafile

@@ -12,5 +12,6 @@ atf_test_program{name="issue6_test"}
 atf_test_program{name="issue18_test"}
 atf_test_program{name="issue20_test"}
 atf_test_program{name="conf_files_test"}
+atf_test_program{name="remove_test"}
 include('find_pkg_orphans/Kyuafile')
 include('pkgdb/Kyuafile')

tests/xbps/libxbps/shell/Makefile

@@ -1,7 +1,7 @@
 TOPDIR = ../../../..
 -include $(TOPDIR)/config.mk
 
-TESTSHELL = conf_files_test issue6_test issue18_test issue20_test
+TESTSHELL = conf_files_test issue6_test issue18_test issue20_test remove_test
 
 include ../Makefile.inc
 include $(TOPDIR)/mk/test.mk

tests/xbps/libxbps/shell/remove_test.sh

@@ -0,0 +1,37 @@
+#! /usr/bin/env atf-sh
+
+# 1st test: make sure that base symlinks on rootdir are not removed.
+atf_test_case keep_base_symlinks
+
+keep_base_symlinks_head() {
+	atf_set "descr" "Tests for package removal: keep base symlinks test"
+}
+
+keep_base_symlinks_body() {
+	mkdir -p root/usr/bin
+	ln -sfr root/usr/bin root/bin
+
+	mkdir some_repo
+	mkdir -p pkg_A/usr/bin pkg_A/bin
+	touch -f pkg_A/usr/bin/foo
+	cd some_repo
+	xbps-create -A noarch -n foo-1.0_1 -s "foo pkg" ../pkg_A
+	atf_check_equal $? 0
+	xbps-rindex -a *.xbps
+	atf_check_equal $? 0
+	cd ..
+	xbps-install -r root --repository=some_repo -y foo
+	atf_check_equal $? 0
+	xbps-remove -r root -y foo
+	atf_check_equal $? 0
+	if [ -h root/bin ]; then
+		rv=0
+	else
+		rv=1
+	fi
+	atf_check_equal $rv 0
+}
+
+atf_init_test_cases() {
+	atf_add_test_case keep_base_symlinks
+}