NodeFragment: added unsafe getter for tag

The library provides a way to directly access the tag in a read-only
way, which saves an call to strdup. This is useful if only reading is
necessary , but needs special care by developers, as it is neither
allowed to modify it nor to free it. Disregarding this will lead to a
segfault in the best, and to silent data corruption and security bugs in
the worst case.

sefht.geany

@@ -28,7 +28,7 @@ long_line_behaviour=1
 long_line_column=72
 
 [files]
-current_page=21
+current_page=27
 FILE_NAME_0=923;Sh;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fconfigure.ac;0;8
 FILE_NAME_1=73;Make;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2FMakefile.am;0;8
 FILE_NAME_2=1143;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Fmain.c;0;8
@@ -41,7 +41,7 @@ FILE_NAME_8=1185;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fpr
 FILE_NAME_9=916;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Ffragment.h;0;8
 FILE_NAME_10=1975;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Ffragment_data.c;0;8
 FILE_NAME_11=2173;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Ffragment_class.c;0;8
-FILE_NAME_12=8225;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Fnode_fragment.c;0;8
+FILE_NAME_12=7399;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Fnode_fragment.c;0;8
 FILE_NAME_13=931;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Fnode_fragment.h;0;8
 FILE_NAME_14=25820;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Ftext.c;0;8
 FILE_NAME_15=904;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Fsrc%2Flib%2Fsefht%2Ftext.h;0;8
@@ -56,7 +56,7 @@ FILE_NAME_23=1078;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fp
 FILE_NAME_24=290;Make;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2FMakefile.am;0;8
 FILE_NAME_25=1085;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2Ftest_cms.c;0;8
 FILE_NAME_26=3283;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2Ftest_data.c;0;8
-FILE_NAME_27=13617;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2Ftest_node_fragment.c;0;8
+FILE_NAME_27=15178;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2Ftest_node_fragment.c;0;8
 FILE_NAME_28=11068;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2Ftest_text.c;0;8
 FILE_NAME_29=5744;C;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftests%2Ftest_validator.c;0;8
 FILE_NAME_30=165;None;0;EUTF-8;1;1;0;%2Fhome%2Fjonathan%2FDokumente%2Fprojekte%2Fprgm%2Finternet%2Fweb%2FSeFHT%2Ftodo.txt;0;8
@@ -71,6 +71,7 @@ ignored_dirs_patterns=.*;CVS;
 ignored_file_patterns=*.o;*.obj;*.a;*.lib;*.so;*.dll;*.lo;*.la;*.class;*.jar;*.pyc;*.mo;*.gmo;
 generate_tag_prefs=0
 external_dirs=
+show_empty_dirs=true
 
 [build-menu]
 NF_00_LB=_Make

src/lib/sefht/node_fragment.c

@@ -46,7 +46,7 @@ struct SH_NodeFragment
 {
 	struct SH_Fragment base;
 
-	char * tag;
+	/*@only@*/ char * tag;
 
 	size_t child_n;
 	struct SH_Fragment ** childs;
@@ -123,6 +123,40 @@ SH_NodeFragment_new (const char * tag,
 	return (struct SH_Fragment *) fragment;
 }
 
+/*@null@*/
+/*@only@*/
+struct SH_Fragment /*@alt struct SH_NodeFragment@*/ *
+SH_NodeFragment_raw_new (/*@only@*/ char * tag,
+                         /*@dependent@*/ SH_Data * data,
+                         /*@out@*/ /*@null@*/ struct SH_Status * status)
+	/*@globals NODE,
+	           fileSystem@*/
+	/*@modifies fileSystem@*/
+	/*@modifies status@*/
+{
+	struct SH_NodeFragment * fragment;
+
+	fragment = malloc (sizeof (struct SH_NodeFragment));
+	if (fragment == NULL)
+	{
+		set_status (status, E_ALLOC, 3,
+		            "Memory allocation for "
+		            "SH_NodeFragment failed.\n");
+
+		return NULL;
+	}
+
+	init_fragment (&(fragment->base), data, NODE, &methods);
+
+	fragment->tag = tag;
+	fragment->child_n = 0;
+	fragment->childs = malloc (0);
+
+	set_success (status);
+
+	return (struct SH_Fragment *) fragment;
+}
+
 void
 SH_NodeFragment_free (/*@only@*/ struct SH_NodeFragment * fragment)
 	/*@modifies fragment@*/
@@ -276,6 +310,15 @@ SH_Fragment_is_NodeFragment (const struct SH_Fragment * fragment)
 	return get_type (fragment) == NODE;
 }
 
+static inline
+/*@observer@*/
+char *
+get_tag (const struct SH_NodeFragment * fragment)
+	/*@*/
+{
+	return fragment->tag;
+}
+
 /*@null@*/
 /*@only@*/
 char *
@@ -287,7 +330,7 @@ SH_NodeFragment_get_tag (const struct SH_NodeFragment * fragment,
 {
 	char * tag;
 
-	tag = strdup (fragment->tag);
+	tag = strdup (get_tag (fragment));
 
 	if (tag == NULL)
 	{
@@ -303,6 +346,13 @@ SH_NodeFragment_get_tag (const struct SH_NodeFragment * fragment,
 	return tag;
 }
 
+/*@observer@*/
+char *
+SH_NodeFragment_raw_get_tag (const struct SH_NodeFragment * fragment)
+{
+	return get_tag (fragment);
+}
+
 /*@null@*/
 /*@observer@*/
 struct SH_Fragment *

tests/test_node_fragment.c

@@ -63,6 +63,38 @@ START_TEST(test_node_fragment)
 }
 END_TEST
 
+START_TEST(test_node_fragment_raw_new)
+{
+	struct SH_Status status;
+	struct SH_Fragment * fragment;
+	struct SH_Data * data;
+	char * tag1 = strdup ("tag");
+	char * tag2 = strdup ("tag");
+
+	data = SH_Data_new (NULL);
+
+	/* valid tag - no error */
+	fragment = SH_NodeFragment_raw_new (tag1, data, NULL);
+	ck_assert_int_ne ((long int) fragment, (long int) NULL);
+
+	ck_assert_ptr_eq (((struct SH_NodeFragment *) fragment)->tag, tag1);
+
+	SH_Fragment_free (fragment);
+
+	/* valid tag - error */
+	_status_preinit (status);
+	fragment = SH_NodeFragment_raw_new (tag2, data, &status);
+	ck_assert_int_ne ((long int) fragment, (long int) NULL);
+	ck_assert_int_eq (status.status, SUCCESS);
+
+	ck_assert_ptr_eq (((struct SH_NodeFragment *) fragment)->tag, tag2);
+
+	SH_Fragment_free (fragment);
+
+	SH_Data_free (data);
+}
+END_TEST
+
 START_TEST(test_node_fragment_copy)
 {
 	struct SH_Status status;
@@ -224,6 +256,9 @@ START_TEST(test_node_fragment_tag)
 	/* no error */
 	fragment = SH_NodeFragment_new (tag1, data, NULL);
 
+	tag = SH_NodeFragment_raw_get_tag (((struct SH_NodeFragment *) fragment));
+	ck_assert_str_eq (tag, tag1);
+
 	tag = SH_NodeFragment_get_tag (((struct SH_NodeFragment *) fragment),
 				       NULL);
 	ck_assert_str_eq (tag, tag1);
@@ -497,6 +532,7 @@ Suite * fragment_suite (void)
 	tc_core = tcase_create ("Core");
 
 	tcase_add_test (tc_core, test_node_fragment);
+	tcase_add_test (tc_core, test_node_fragment_raw_new);
 	tcase_add_test (tc_core, test_node_fragment_copy);
 	tcase_add_test (tc_core, test_node_fragment_deepcopy);
 	tcase_add_test (tc_core, test_node_fragment_tag);