libxbps: detect and remove properly symlinks with relative targets.

Close #78

NEWS

@@ -1,5 +1,8 @@
 xbps-0.44 (???):
 
+ * libxbps: make sure that symlinks with relative target are detected and removed
+   properly. Fix #78: https://github.com/voidlinux/xbps/issues/78
+
  * xbps-checkvers(8): this now does not segfault anymore when the source package
    does not set required variables (pkgname/version/revision). Added new test
    cases to verify its correctness.

lib/package_remove.c

@@ -96,7 +96,7 @@ static char *
 symlink_target(struct xbps_handle *xhp, const char *path)
 {
 	struct stat sb;
-	char *lnk, *res;
+	char *lnk, *res = NULL;
 	ssize_t r;
 
 	if (lstat(path, &sb) == -1)
@@ -111,16 +111,23 @@ symlink_target(struct xbps_handle *xhp, const char *path)
 		return NULL;
 	}
 	lnk[sb.st_size] = '\0';
-	if (lnk[0] != '/') {
+	if (strstr(lnk, "./") || lnk[0] != '/') {
-		char *p, *dname;
+		char *p, *p1, *dname;
 
 		/* relative */
 		p = strdup(path);
 		assert(p);
 		dname = dirname(p);
 		assert(dname);
-		dname += strlen(xhp->rootdir) + 1;
+		p = xbps_xasprintf("%s/%s", dname, lnk);
-		res = xbps_xasprintf("%s/%s", dname, lnk);
+		assert(p);
+		if (strstr(p, "./") && ((p1 = realpath(p, NULL)))) {
+			res = strdup(p1 + strlen(xhp->rootdir));
+		}
+		if (res == NULL) {
+			res = strdup(p + strlen(xhp->rootdir)+1);
+		}
+		assert(res);
 		free(lnk);
 		free(p);
 	} else {
@@ -375,15 +382,15 @@ xbps_remove_pkg(struct xbps_handle *xhp, const char *pkgver, bool update)
 			rv = EPERM;
 			goto out;
 		}
+		/* Remove links */
+		if ((rv = remove_pkg_files(xhp, pkgfilesd, "links", pkgver)) != 0)
+			goto out;
 		/* Remove regular files */
 		if ((rv = remove_pkg_files(xhp, pkgfilesd, "files", pkgver)) != 0)
 			goto out;
 		/* Remove configuration files */
 		if ((rv = remove_pkg_files(xhp, pkgfilesd, "conf_files", pkgver)) != 0)
 			goto out;
-		/* Remove links */
-		if ((rv = remove_pkg_files(xhp, pkgfilesd, "links", pkgver)) != 0)
-			goto out;
 		/* Remove dirs */
 		if ((rv = remove_pkg_files(xhp, pkgfilesd, "dirs", pkgver)) != 0)
 			goto out;

tests/xbps/libxbps/shell/remove_test.sh

@@ -62,7 +62,7 @@ remove_symlinks_body() {
 	xbps-rindex -d -a $PWD/*.xbps
 	atf_check_equal $? 0
 	cd ..
-	xbps-install -r root -C null.conf --repository=$PWD/some_repo -y B
+	xbps-install -r root --repository=$PWD/some_repo -y B
 	atf_check_equal $? 0
 	xbps-pkgdb -r root -m manual A
 	atf_check_equal $? 0
@@ -75,6 +75,35 @@ remove_symlinks_body() {
 	atf_check_equal $rv 0
 }
 
+atf_test_case remove_symlinks_relative
+
+remove_symlinks_relative_head() {
+	atf_set "descr" "Tests for package removal: relative symlink cleanup test"
+}
+
+remove_symlinks_relative_body() {
+	mkdir some_repo
+	mkdir -p pkg_A/usr/lib pkg_A/usr/share/lib
+	touch -f pkg_A/usr/lib/libfoo.so.1.2.0
+	ln -sfr pkg_A/usr/lib/libfoo.so.1.2.0 pkg_A/usr/share/lib/libfoo.so.1
+
+	cd some_repo
+	xbps-create -A noarch -n A-1.0_1 -s "A pkg" ../pkg_A
+	atf_check_equal $? 0
+	xbps-rindex -d -a $PWD/*.xbps
+	atf_check_equal $? 0
+	cd ..
+	xbps-install -r root --repository=$PWD/some_repo -y A
+	atf_check_equal $? 0
+	xbps-remove -r root -Ryvd A
+	atf_check_equal $? 0
+	rv=0
+	if [ -h root/usr/share/lib/libfoo.so.1 -o -h root/usr/lib/libfoo.so.1.2.0 -o -d root/usr/share/lib -o -d root/usr/lib ]; then
+	        rv=1
+	fi
+	atf_check_equal $rv 0
+}
+
 # 3rd test: make sure that symlinks to the rootfs are also removed.
 atf_test_case remove_symlinks_from_root
 
@@ -353,6 +382,7 @@ atf_init_test_cases() {
 	atf_add_test_case keep_modified_symlinks
 	atf_add_test_case remove_readonly_files
 	atf_add_test_case remove_symlinks
+	atf_add_test_case remove_symlinks_relative
 	atf_add_test_case remove_symlinks_from_root
 	atf_add_test_case remove_symlinks_modified
 	atf_add_test_case remove_dups