Add support for tree structures. Search function with DFS, BFS currently unimplemented. Improve linked list handling; fix bug in circular list detection.

CMakeLists.txt

@@ -67,4 +67,9 @@ install(FILES
     DESTINATION ${akstdlib_install_cmakedir}
 )
 
+add_executable(test_linkedlist tests/test_linkedlist.c)
+target_link_libraries(test_linkedlist PRIVATE akstdlib)
+add_test(NAME linkedlist COMMAND test_linkedlist)
+
+
 # pkgconfig

include/akstdlib.h

@@ -7,6 +7,32 @@
 #include <string.h>
 #include <stdint.h>
 
+typedef struct aksl_ListNode {
+    void *data;
+    struct aksl_ListNode *next;
+    struct aksl_ListNode *prev;
+} aksl_ListNode;
+
+typedef struct aksl_TreeNode {
+    struct aksl_TreeNode *parent;
+    struct aksl_TreeNode *left;
+    struct aksl_TreeNode *right;
+    void *leaf;
+} aksl_TreeNode;
+
+#define AKSL_TREE_SEARCH_BFS           0    /** Breadth-first search mode for tree nodes. Currently unsupported. */
+#define AKSL_TREE_SEARCH_BFS_RIGHT     1    /** Right-hand breadth-first search mode for tree nodes. Currentl unsupported. */
+#define AKSL_TREE_SEARCH_DFS           2    /** Alias for AKSL_TREE_SEARCH_DFS_PREORDER */
+#define AKSL_TREE_SEARCH_DFS_PREORDER  2    /** Depth first pre-order (root, left, right) search mode for tree nodes */
+#define AKSL_TREE_SEARCH_DFS_INORDER   3    /** Depth first in-order (left, root, right) search mode for tree nodes. Currently unsupported. */
+#define AKSL_TREE_SEARCH_DFS_POSTORDER 4    /** Depth first post-order (left, right, root) search mode for tree nodes. Currently unsupported. */
+#define AKSL_TREE_SEARCH_VISIT         5    /** Used when iterating through a tree structure as a control flag: don't traverse the children, just visit the node */
+
+typedef akerr_ErrorContext AKERR_NOIGNORE *(*aksl_ListNodeIterator)(aksl_ListNode *node, void *data);
+typedef akerr_ErrorContext AKERR_NOIGNORE *(*aksl_TreeNodeIterator)(aksl_TreeNode *node, void *data);
+typedef akerr_ErrorContext AKERR_NOIGNORE *(*aksl_AllocFunc)(size_t size, void **dest);
+typedef akerr_ErrorContext AKERR_NOIGNORE *(*aksl_FreeFunc)(void *ptr);
+
 akerr_ErrorContext AKERR_NOIGNORE *aksl_fopen(char *pathname, char *mode, FILE **fp);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_fwrite(void *ptr, size_t size, size_t nmemb, FILE *fp);
@@ -17,7 +43,6 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_memset(void *s, int c, size_t n);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_memcpy(void *d, void *s, size_t n);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_free(void *ptr);
 
-
 akerr_ErrorContext AKERR_NOIGNORE *aksl_printf(int *count, const char *restrict format, ...);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_fprintf(int *count, FILE *restrict stream, const char *restrict format, ...);
 akerr_ErrorContext AKERR_NOIGNORE *aksl_sprintf(int *count, char *restrict str, const char *restrict format, ...);
@@ -31,4 +56,12 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_realpath(const char *restrict path, char
 
 akerr_ErrorContext AKERR_NOIGNORE *aksl_strhash_djb2(char *str, size_t len, uint32_t *hashval);
 
+// Linked list functions
+akerr_ErrorContext AKERR_NOIGNORE *aksl_list_push(aksl_ListNode *list, aksl_ListNode *obj);
+akerr_ErrorContext AKERR_NOIGNORE *aksl_list_pop(aksl_ListNode *node);
+akerr_ErrorContext AKERR_NOIGNORE *aksl_list_iterate(aksl_ListNode *list, aksl_ListNodeIterator iter, void *data);
+
+// Tree functions
+akerr_ErrorContext AKERR_NOIGNORE *aksl_tree_iterate(aksl_TreeNode *root, aksl_TreeNodeIterator iter, aksl_AllocFunc lalloc, aksl_FreeFunc lfree, uint8_t searchmode, void *data, aksl_ListNode *queue);
+
 #endif

src/stdlib.c

@@ -99,6 +99,7 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_printf(int *count, const char *restrict
     PREPARE_ERROR(e);
     FAIL_ZERO_RETURN(e, count, AKERR_NULLPOINTER, "count=%p, format=%p", (void *)count, (void *)format);
     FAIL_ZERO_RETURN(e, format, AKERR_NULLPOINTER, "count=%p, format=%p", (void *)count, (void *)format);
+    va_start(args, format);    
     *count = vprintf(format, args);
     FAIL_NONZERO_RETURN(e, (*count == -1), errno, "Short write");
     SUCCEED_RETURN(e);
@@ -112,6 +113,7 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_fprintf(int *count, FILE *restrict strea
     FAIL_ZERO_RETURN(e, count, AKERR_NULLPOINTER, "count=%p, stream=%p, format=%p", (void *)count, (void *)stream, (void *)format);
     FAIL_ZERO_RETURN(e, stream, AKERR_NULLPOINTER, "count=%p, stream=%p, format=%p", (void *)count, (void *)stream, (void *)format);
     FAIL_ZERO_RETURN(e, format, AKERR_NULLPOINTER, "count=%p, stream=%p, format=%p", (void *)count, (void *)stream, (void *)format);
+    va_start(args, format);
     *count = vfprintf(stream, format, args);
     FAIL_NONZERO_RETURN(e, (*count == -1), errno, "Short write");
     SUCCEED_RETURN(e);
@@ -188,3 +190,146 @@ akerr_ErrorContext AKERR_NOIGNORE *aksl_strhash_djb2(char *str, size_t len, uint
     *hashval = h;
     SUCCEED_RETURN(e);
 }
+
+akerr_ErrorContext AKERR_NOIGNORE *aksl_list_push(aksl_ListNode *list, aksl_ListNode *obj)
+{
+    PREPARE_ERROR(e);
+    FAIL_ZERO_RETURN(e, list, AKERR_NULLPOINTER, "list");
+    FAIL_ZERO_RETURN(e, obj, AKERR_NULLPOINTER, "obj");
+    aksl_ListNode *slow = list;
+    aksl_ListNode *fast = list;
+    aksl_ListNode *tail = list;
+    do { 
+	if ( fast != NULL && fast->next != NULL ) {
+	    fast = fast->next->next;
+	}
+	tail = slow;
+	slow = slow->next;
+	if ( fast != NULL && fast == slow) {
+	    FAIL(e, AKERR_CIRCULAR_REFERENCE, "%p", list);
+	}
+    } while ( slow != NULL || (fast != NULL && fast->next != NULL) );
+    tail->next = obj;
+    obj->next = NULL;
+    obj->prev = slow;
+    SUCCEED_RETURN(e);
+}
+
+akerr_ErrorContext AKERR_NOIGNORE *aksl_list_pop(aksl_ListNode *node)
+{
+    PREPARE_ERROR(e);
+    FAIL_ZERO_RETURN(e, node, AKERR_NULLPOINTER, "node");
+    if ( node->prev != NULL ) {
+	node->prev->next = node->next;
+    }
+    if ( node->next != NULL ) {	
+	node->next->prev = node->prev;
+    }
+    node->next = NULL;
+    node->prev = NULL;
+    SUCCEED_RETURN(e);
+}
+
+/**
+ * @brief Iterates over a tree structure in breadth or depth first order, executing a callback function on each node.
+ *
+ * This function recursively calls itself to traverse a binary tree datastructure. 
+ *
+ * @param[in] root The tree structure to search
+ * @param[in] iter An aksl_TreeNodeIterator function which will be called for each node found
+ * @param[in] lalloc An aksl_AllocFunc function which will be used to allocate aksl_ListNode elements for the search, or NULL to use the default allocator (aksl_malloc)
+ * @param[in] lfree An aksl_FreeFunc function which will be used to free the elements procured with lalloc, or NULL to use the default free function (aksl_free)
+ * @param[in] searchmode One of the AKSL_TREE_SEARCH_BFS* defines
+ * @param[in] data Any user data that should be provided when the iterator is called
+ * @param[in] queue The linked list node to use as the head of the queue. The caller should pass NULL here.
+ *
+ * @throws AKERR_NULLPOINTER On null pointer inputs
+ * @return akerr_ErrorContext
+ */
+
+akerr_ErrorContext AKERR_NOIGNORE *aksl_tree_iterate(
+    aksl_TreeNode *root,
+    aksl_TreeNodeIterator iter,
+    aksl_AllocFunc lalloc,
+    aksl_FreeFunc lfree,
+    uint8_t searchmode,
+    void *data,
+    aksl_ListNode *queue)
+{
+    PREPARE_ERROR(e);
+    FAIL_ZERO_RETURN(e, root, AKERR_NULLPOINTER, "root");
+    FAIL_ZERO_RETURN(e, iter, AKERR_NULLPOINTER, "iter");
+    if ( lalloc == NULL ) {
+	lalloc = &aksl_malloc;
+    }
+    if ( lfree == NULL ) {
+	lfree = &aksl_free;
+    }
+    switch ( searchmode ) {
+    case AKSL_TREE_SEARCH_DFS_PREORDER:
+	PASS(e, iter(root, data));
+	if ( root->left != NULL ) {
+	    PASS(e, aksl_tree_iterate(root->left, iter, lalloc, lfree, searchmode, data, NULL));
+	}
+	if ( root-> right != NULL ) {
+	    PASS(e, aksl_tree_iterate(root->right, iter, lalloc, lfree, searchmode, data, NULL));
+	}
+	break;
+    case AKSL_TREE_SEARCH_DFS_POSTORDER:
+	if ( root->left != NULL ) {
+	    PASS(e, aksl_tree_iterate(root->left, iter, lalloc, lfree, searchmode, data, NULL));
+	}
+	if ( root-> right != NULL ) {
+	    PASS(e, aksl_tree_iterate(root->right, iter, lalloc, lfree, searchmode, data, NULL));
+	}
+	PASS(e, iter(root, data));
+	break;
+    case AKSL_TREE_SEARCH_DFS_INORDER:
+	if ( root->left != NULL ) {
+	    PASS(e, aksl_tree_iterate(root->left, iter, lalloc, lfree, searchmode, data, NULL));
+	}
+	PASS(e, iter(root, data));
+	if ( root-> right != NULL ) {
+	    PASS(e, aksl_tree_iterate(root->right, iter, lalloc, lfree, searchmode, data, NULL));
+	}
+	break;
+    case AKSL_TREE_SEARCH_BFS:
+    case AKSL_TREE_SEARCH_BFS_RIGHT:
+	FAIL_RETURN(e, AKERR_NOT_IMPLEMENTED, "Searchmode %d", searchmode);
+	break;
+    }
+    SUCCEED_RETURN(e);
+}
+
+/**
+ * @brief Iterates over a linked list and execute a callback function on each node
+ *
+ * @param[in] list The linked list to iterate
+ * @param[in] iter An aksl_ListNodeIterator function which will be called for each node found
+ * @param[in] data Any user data that should be provided when the iterator is called
+ *
+ * @throws AKERR_NULLPOINTER on null pointer inputs
+ * @throws AKERR_CIRCULAR_REFERENCE when the linked list contains a circular reference
+ * 
+ * @return akerr_ErrorContext
+ */
+akerr_ErrorContext AKERR_NOIGNORE *aksl_list_iterate(aksl_ListNode *list, aksl_ListNodeIterator iter, void *data)
+{
+    PREPARE_ERROR(e);
+    FAIL_ZERO_RETURN(e, list, AKERR_NULLPOINTER, "list");
+    FAIL_ZERO_RETURN(e, iter, AKERR_NULLPOINTER, "iter");
+    aksl_ListNode *slow = list;
+    aksl_ListNode *fast = list;
+    aksl_ListNode *tail = list;
+    do {
+	if ( fast != NULL && fast->next != NULL ) {
+	    fast = fast->next->next;
+	}
+	PASS(e, iter(slow, data));
+	slow = slow->next;
+	if ( fast != NULL && fast == slow) {
+	    FAIL(e, AKERR_CIRCULAR_REFERENCE, "%p", list);
+	}
+    } while ( slow != NULL || (fast != NULL && fast->next != NULL) );
+    SUCCEED_RETURN(e);
+}

tests/test_linkedlist.c

@@ -0,0 +1,33 @@
+#include <akstdlib.h>
+
+akerr_ErrorContext AKERR_NOIGNORE *myiter(aksl_ListNode *node, void *data)
+{
+	PREPARE_ERROR(e);
+	int count;
+	FAIL_ZERO_RETURN(e, node, AKERR_NULLPOINTER, "node");
+	FAIL_ZERO_RETURN(e, node->data, AKERR_NULLPOINTER, "node->data");
+	// This function doesn't use *data so we don't check it
+	
+	PASS(e, aksl_fprintf(&count, stderr, "Visiting node : %s", node->data));
+	SUCCEED_RETURN(e);
+}
+
+int main(void)
+{
+	PREPARE_ERROR(e);
+	aksl_ListNode mylist;
+	char *node1str = "Node 1";
+	aksl_ListNode node1;
+	char *node2str = "Node 2";
+	aksl_ListNode node2;
+
+	node1->data = (void *)&node1str;
+	PASS(e, aksl_list_push(&mylist, &node1));
+
+	node2->data = (void *)&node2str;
+	PASS(e, aksl_list_push(&mylist, &node2));
+	
+	PASS(e, aksl_list_iterate(&mylist, &myiter, NULL));
+	
+	SUCCEED_RETURN(e);
+}