diff --git a/LICENSE b/LICENSE
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--- /dev/null
+++ b/LICENSE
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+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc.
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+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/Makefile b/Makefile
index 04c6dd3..fadf89d 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,7 @@ INC_DIRS ?= include
LIB := $(BUILD_DIR)/$(LIB_FILENAME)
SRCS != find '$(SRC_DIR)' -iname '*.c'
-SRCS_H != find $(INC_DIRS) -iname '*.h'
+SRCS_H != find $(INC_DIRS) '$(SRC_DIR)' -iname '*.h'
SRCS_TEST != find '$(TEST_DIR)' -iname '*.c'
OBJS := $(SRCS:%=$(BUILD_DIR)/%.o)
@@ -43,7 +43,7 @@ objs: $(OBJS)
.PHONY: vieter
vieter: $(LIB)
-$(BUILD_DIR)/$(LIB_FILENAME): $(OBJS)
+$(LIB): $(OBJS)
ar -rcs $@ $(OBJS)
$(BUILD_DIR)/$(SRC_DIR)/%.c.o: $(SRC_DIR)/%.c
@@ -69,8 +69,6 @@ $(TARGETS_MEM_TEST): test-mem-%: %
.PHONY: build-test
build-test: $(BINS_TEST)
-# For simplicity, we link every object file to each of the test files. This
-# might be changed later if this starts to become too slow.
$(BINS_TEST): %: %.c.o $(LIB)
$(CC) \
$^ -o $@
diff --git a/README.md b/README.md
index d1fef1a..abc250a 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,17 @@ files defined in its respective module. This allows testing internal functions.
To run the tests, simply run `make test`. If you wish to only run a specific
test binary, you can find them in `build/test`.
+The name of tests in the `TEST_LIST` variable should be prefixed with the
+module they're testing. This makes it much easier to distinguish the output of
+tests in the CLI. For example:
+
+```c
+TEST_LIST = {
+ {"cron illegal parts", test_illegal_parts},
+ {NULL, NULL}
+};
+```
+
### `compile_commands.json`
Clangd requires a `compile_commands.json` to function properly. You can
diff --git a/include/vieter_tree.h b/include/vieter_tree.h
new file mode 100644
index 0000000..2079eb9
--- /dev/null
+++ b/include/vieter_tree.h
@@ -0,0 +1,70 @@
+#ifndef VIETER_TREE
+#define VIETER_TREE
+
+#include
+#include
+
+typedef struct vieter_tree vieter_tree;
+
+typedef enum vieter_tree_error {
+ vieter_tree_ok = 0,
+ vieter_tree_already_present = 1,
+ vieter_tree_not_present = 2,
+ vieter_tree_iterator_done = 3
+} vieter_tree_error;
+
+/*
+ * Allocate and initialize a new red-black binary tree.
+ */
+vieter_tree *vieter_tree_init();
+
+/*
+ * Deallocate a red-black binary tree.
+ */
+void vieter_tree_free(vieter_tree *tree);
+
+/*
+ * Insert a new entry into the tree.
+ */
+vieter_tree_error vieter_tree_insert(vieter_tree *tree, uint64_t key,
+ void *data);
+
+/*
+ * Look for an entry in the tree.
+ */
+vieter_tree_error vieter_tree_search(void **out, vieter_tree *tree,
+ uint64_t key);
+
+/*
+ * Remove a given entry from the tree.
+ */
+vieter_tree_error vieter_tree_remove(void **out, vieter_tree *tree,
+ uint64_t key);
+
+/*
+ * Return how many entries are currently in the tree.
+ */
+uint64_t vieter_tree_size(vieter_tree *tree);
+
+/*
+ * An iterator that can be used to traverse a tree in-order.
+ */
+typedef struct vieter_tree_iterator vieter_tree_iterator;
+
+/*
+ * Allocate and initialize a new iterator from the given tree.
+ */
+vieter_tree_iterator *vieter_tree_iterator_from(vieter_tree *tree);
+
+/*
+ * Free an iterator.
+ */
+void vieter_tree_iterator_free(vieter_tree_iterator **ptp);
+
+/*
+ * Return the iterator's next element.
+ */
+vieter_tree_error vieter_tree_iterator_next(void **out,
+ vieter_tree_iterator *iter);
+
+#endif
diff --git a/src/cron/vieter_cron_parse.c b/src/cron/vieter_cron_parse.c
index a82d1c3..b42e1a9 100644
--- a/src/cron/vieter_cron_parse.c
+++ b/src/cron/vieter_cron_parse.c
@@ -1,4 +1,4 @@
-#include "vieter_cron.h"
+#include "vieter_cron_parse.h"
#include
#include
#include
diff --git a/src/cron/vieter_cron_parse.h b/src/cron/vieter_cron_parse.h
new file mode 100644
index 0000000..21ccf81
--- /dev/null
+++ b/src/cron/vieter_cron_parse.h
@@ -0,0 +1,11 @@
+#ifndef VIETER_CRON_PARSE
+#define VIETER_CRON_PARSE
+
+#include "vieter_cron.h"
+
+vieter_cron_parse_error vieter_cron_expr_parse_range(uint64_t *out, char *s,
+ uint8_t min, uint8_t max);
+
+vieter_cron_parse_error vieter_cron_expr_parse_part(uint64_t *out, char *s,
+ uint8_t min, uint8_t max);
+#endif
diff --git a/src/heap/vieter_heap_tree.h b/src/heap/vieter_heap_tree.h
index 0a299db..615491a 100644
--- a/src/heap/vieter_heap_tree.h
+++ b/src/heap/vieter_heap_tree.h
@@ -5,16 +5,16 @@
#include
typedef struct vieter_heap_node {
- uint64_t key;
- void *data;
- struct vieter_heap_node *largest_order;
- union {
- // Roots point to next tree in the heap, other nodes point to their first
- // neighbour.
- struct vieter_heap_node *next_tree;
- struct vieter_heap_node *next_largest_order;
- } ptr;
- uint8_t order;
+ uint64_t key;
+ void *data;
+ struct vieter_heap_node *largest_order;
+ union {
+ // Roots point to next tree in the heap, other nodes point to their first
+ // neighbour.
+ struct vieter_heap_node *next_tree;
+ struct vieter_heap_node *next_largest_order;
+ } ptr;
+ uint8_t order;
} vieter_heap_node;
/*
@@ -36,7 +36,8 @@ void vieter_heap_tree_free(vieter_heap_node *root);
* Given the roots of the smallest trees in two heaps, merge them into a single
* large heap.
*/
-vieter_heap_node *vieter_heap_tree_merge(vieter_heap_node *root_a, vieter_heap_node *root_b);
+vieter_heap_node *vieter_heap_tree_merge(vieter_heap_node *root_a,
+ vieter_heap_node *root_b);
/*
* Given the roots of two trees of the same order, merge them into a heap of one
diff --git a/src/tree/vieter_tree.c b/src/tree/vieter_tree.c
new file mode 100644
index 0000000..84a1a26
--- /dev/null
+++ b/src/tree/vieter_tree.c
@@ -0,0 +1,116 @@
+#include "vieter_tree_balancing.h"
+#include "vieter_tree_internal.h"
+
+vieter_tree *vieter_tree_init() { return calloc(1, sizeof(vieter_tree)); }
+
+uint64_t vieter_tree_size(vieter_tree *tree) { return tree->size; }
+
+vieter_tree_error vieter_tree_insert(vieter_tree *tree, uint64_t key,
+ void *data) {
+ if (tree->size == 0) {
+ tree->root = vieter_tree_node_init();
+ tree->root->key = key;
+ tree->root->data = data;
+ vieter_tree_node_set(tree->root, vieter_tree_node_black, true);
+ tree->size = 1;
+
+ return vieter_tree_ok;
+ }
+
+ vieter_tree_error res = vieter_tree_node_insert(tree->root, key, data);
+
+ if (res != vieter_tree_ok) {
+ return res;
+ }
+
+ tree->size++;
+
+ return vieter_tree_ok;
+}
+
+vieter_tree_error vieter_tree_search(void **out, vieter_tree *tree,
+ uint64_t key) {
+ if (tree->size == 0) {
+ return vieter_tree_not_present;
+ }
+
+ return vieter_tree_node_search(out, tree->root, key);
+}
+
+vieter_tree_error vieter_tree_remove(void **out, vieter_tree *tree,
+ uint64_t key) {
+ if (tree->size == 0) {
+ return vieter_tree_not_present;
+ }
+
+ vieter_tree_error res = vieter_tree_node_remove(out, &tree->root, key);
+
+ if (res != vieter_tree_ok) {
+ return res;
+ }
+
+ tree->size--;
+
+ return vieter_tree_ok;
+}
+
+void vieter_tree_free(vieter_tree *tree) {
+ if (tree->size == 0) {
+ goto end;
+ }
+
+ uint64_t capacity = 4;
+ uint64_t size = 1;
+ vieter_tree_node **stack = malloc(capacity * sizeof(vieter_tree_node *));
+ stack[0] = tree->root;
+
+ vieter_tree_node *node;
+
+ while (size > 0) {
+ node = stack[size - 1];
+ size--;
+
+ if (size + 2 > capacity) {
+ capacity *= 2;
+ stack = realloc(stack, capacity * sizeof(vieter_tree_node *));
+ }
+
+ if (node->children[0] != NULL) {
+ stack[size] = node->children[0];
+ size++;
+ }
+
+ if (node->children[1] != NULL) {
+ stack[size] = node->children[1];
+ size++;
+ }
+
+ vieter_tree_node_free(node);
+ }
+
+ free(stack);
+
+end:
+ free(tree);
+}
+
+bool vieter_tree_validate(vieter_tree *tree) {
+ if (tree->size == 0) {
+ return true;
+ }
+
+ // DFS to get expected black nodes
+ uint64_t expected_black_nodes = 0;
+ vieter_tree_node *node = tree->root;
+
+ while (node != NULL) {
+ if (vieter_tree_node_get(node, vieter_tree_node_black)) {
+ expected_black_nodes++;
+ }
+
+ node = node->children[0];
+ }
+
+ return vieter_tree_node_get(tree->root, vieter_tree_node_black) &&
+ vieter_tree_node_validate(tree->root, 0, expected_black_nodes);
+}
diff --git a/src/tree/vieter_tree_balancing.c b/src/tree/vieter_tree_balancing.c
new file mode 100644
index 0000000..6e7dcd9
--- /dev/null
+++ b/src/tree/vieter_tree_balancing.c
@@ -0,0 +1,289 @@
+#include "vieter_tree_balancing.h"
+#include
+
+bool vieter_tree_node_validate(vieter_tree_node *node,
+ uint64_t passed_black_nodes,
+ uint64_t expected_black_nodes) {
+ // Path to NULL children should contain the same amount of black nodes
+ if (node == NULL) {
+ return passed_black_nodes == expected_black_nodes;
+ }
+
+ if (vieter_tree_node_get(node, vieter_tree_node_black)) {
+ passed_black_nodes++;
+ }
+
+ // Either the node itself is black, or its children are both either NULL or
+ // black.
+ bool correctly_colored_children =
+ vieter_tree_node_get(node, vieter_tree_node_black) ||
+ ((node->children[0] == NULL ||
+ vieter_tree_node_get(node->children[0], vieter_tree_node_black)) &&
+ (node->children[1] == NULL ||
+ vieter_tree_node_get(node->children[1], vieter_tree_node_black)));
+ bool right_child_flag_set =
+ node->parent == NULL ||
+ (vieter_tree_node_get(node, vieter_tree_node_right) ==
+ (node->parent->children[1] == node));
+
+ return correctly_colored_children && right_child_flag_set &&
+ vieter_tree_node_validate(node->children[0], passed_black_nodes,
+ expected_black_nodes) &&
+ vieter_tree_node_validate(node->children[1], passed_black_nodes,
+ expected_black_nodes);
+}
+
+/*
+ * This function should be rewritten to use tree rotations instead.
+ */
+vieter_tree_node *vieter_tree_node_balance(vieter_tree_node *node) {
+ vieter_tree_node *parent = node->parent;
+ vieter_tree_node *grand_parent = parent->parent;
+ vieter_tree_node *root = grand_parent;
+ vieter_tree_node *children[2];
+ vieter_tree_node *grand_children[4];
+
+ uint64_t key_root = root->key;
+ void *data_root = root->data;
+
+ if (vieter_tree_node_get(node, vieter_tree_node_right)) {
+ children[0] = parent;
+ children[1] = node;
+
+ if (vieter_tree_node_get(parent, vieter_tree_node_right)) {
+ root->key = parent->key;
+ root->data = parent->data;
+
+ parent->key = key_root;
+ parent->data = data_root;
+
+ grand_children[0] = grand_parent->children[0];
+ grand_children[1] = parent->children[0];
+ grand_children[2] = node->children[0];
+ grand_children[3] = node->children[1];
+ } else {
+ root->key = node->key;
+ root->data = node->data;
+
+ node->key = key_root;
+ node->data = data_root;
+
+ grand_children[0] = parent->children[0];
+ grand_children[1] = node->children[0];
+ grand_children[2] = node->children[1];
+ grand_children[3] = grand_parent->children[1];
+ }
+ } else {
+ children[0] = node;
+ children[1] = parent;
+
+ if (vieter_tree_node_get(parent, vieter_tree_node_right)) {
+ root->key = node->key;
+ root->data = node->data;
+
+ node->key = key_root;
+ node->data = data_root;
+
+ grand_children[0] = grand_parent->children[0];
+ grand_children[1] = node->children[0];
+ grand_children[2] = node->children[1];
+ grand_children[3] = parent->children[1];
+ } else {
+ root->key = parent->key;
+ root->data = parent->data;
+
+ parent->key = key_root;
+ parent->data = data_root;
+
+ grand_children[0] = node->children[0];
+ grand_children[1] = node->children[1];
+ grand_children[2] = parent->children[1];
+ grand_children[3] = grand_parent->children[1];
+ }
+ }
+
+ vieter_tree_node_set(
+ root, vieter_tree_node_right,
+ vieter_tree_node_get(grand_parent, vieter_tree_node_right));
+
+ vieter_tree_node_set(children[0], vieter_tree_node_black, true);
+ vieter_tree_node_set(children[1], vieter_tree_node_black, true);
+
+ vieter_tree_node_set(root, vieter_tree_node_black, false);
+
+ vieter_tree_node_set_children(children[0], grand_children);
+ vieter_tree_node_set_children(children[1], grand_children + 2);
+ vieter_tree_node_set_children(root, children);
+
+ return root;
+}
+
+void vieter_tree_node_balance_after_insert(vieter_tree_node *node) {
+ while (!vieter_tree_node_get(node, vieter_tree_node_black) &&
+ node->parent != NULL &&
+ !vieter_tree_node_get(node->parent, vieter_tree_node_black)) {
+ node = vieter_tree_node_balance(node);
+ }
+
+ // The root must always be black
+ if (node->parent == NULL) {
+ vieter_tree_node_set(node, vieter_tree_node_black, true);
+ }
+}
+
+vieter_tree_node *vieter_tree_node_rotate(vieter_tree_node *old_root,
+ bool dir) {
+ vieter_tree_node *new_root = old_root->children[1 - dir];
+
+ if (old_root->parent != NULL) {
+ vieter_tree_node_set_child(
+ old_root->parent, new_root,
+ vieter_tree_node_get(old_root, vieter_tree_node_right));
+ } else {
+ new_root->parent = NULL;
+ }
+
+ // Right rotation
+ if (dir) {
+ vieter_tree_node_set_child(old_root, new_root->children[1], false);
+ vieter_tree_node_set_child(new_root, old_root, true);
+ }
+ // Left rotation
+ else {
+ vieter_tree_node_set_child(old_root, new_root->children[0], true);
+ vieter_tree_node_set_child(new_root, old_root, false);
+ }
+
+ return new_root;
+}
+
+/*
+ * This function is currently implemented by very literally following the
+ * Wikipedia pseudocode. It's honestly not too bad, and I couldn't be bothered
+ * to properly research how to implement red-black removal (how is this so hard
+ * to find?)
+ *
+ * https://en.wikipedia.org/wiki/Red%E2%80%93black_tree#Removal_of_a_black_non-root_leaf
+ */
+vieter_tree_node *vieter_tree_node_remove_balanced(vieter_tree_node *node) {
+ vieter_tree_node *out;
+
+ if (node->parent == NULL) {
+ out = node->children[0] != NULL ? node->children[0] : node->children[1];
+
+ vieter_tree_node_free(node);
+
+ // This only happens when the root was the only element in the tree
+ if (out == NULL)
+ return out;
+
+ vieter_tree_node_set(out, vieter_tree_node_black, true);
+ out->parent = NULL;
+
+ return out;
+ }
+
+ // A red node can only have 0 or 2 children. The node we receive only has
+ // one child at most, so we know if it's red that it doesn't have any
+ // children. A black node that has a single (right) child can be replaced by
+ // this child, granted it becomes black as well. Either way, the node can be
+ // replaced by its right child (even if it's NULL).
+ if (!vieter_tree_node_get(node, vieter_tree_node_black) ||
+ node->children[1] != NULL) {
+ out = node->children[1];
+
+ vieter_tree_node_set_child(
+ node->parent, node->children[1],
+ vieter_tree_node_get(node, vieter_tree_node_right));
+
+ if (node->children[1] != NULL)
+ vieter_tree_node_set(node->children[1], vieter_tree_node_black, true);
+
+ vieter_tree_node_free(node);
+
+ return out;
+ }
+
+ // The complicated case is when we want to remove a black leaf
+ // https://en.wikipedia.org/wiki/Red%E2%80%93black_tree#Removal_of_a_black_non-root_leaf
+
+ out = node;
+ vieter_tree_node *parent = node->parent;
+ vieter_tree_node *sibling, *close_nephew, *distant_nephew;
+ bool dir = vieter_tree_node_get(node, vieter_tree_node_right);
+ parent->children[dir] = NULL;
+
+ vieter_tree_node_free(node);
+
+ goto start;
+
+ do {
+ dir = vieter_tree_node_get(node, vieter_tree_node_right);
+
+ start:
+ sibling = parent->children[1 - dir];
+ distant_nephew = sibling->children[1 - dir];
+ close_nephew = sibling->children[dir];
+
+ if (!vieter_tree_node_get(sibling, vieter_tree_node_black))
+ goto case3;
+
+ if (distant_nephew != NULL &&
+ !vieter_tree_node_get(distant_nephew, vieter_tree_node_black))
+ goto case6;
+
+ if (close_nephew != NULL &&
+ !vieter_tree_node_get(close_nephew, vieter_tree_node_black))
+ goto case5;
+
+ if (!vieter_tree_node_get(parent, vieter_tree_node_black))
+ goto case4;
+
+ // Case 2
+ vieter_tree_node_set(sibling, vieter_tree_node_black, false);
+ node = parent;
+ out = node;
+ } while ((parent = node->parent) != NULL);
+
+ // Case 1
+ return out;
+
+case3:
+ out = vieter_tree_node_rotate(parent, dir);
+ vieter_tree_node_set(parent, vieter_tree_node_black, false);
+ vieter_tree_node_set(sibling, vieter_tree_node_black, true);
+ sibling = close_nephew;
+ distant_nephew = sibling->children[1 - dir];
+
+ if (distant_nephew != NULL &&
+ !vieter_tree_node_get(distant_nephew, vieter_tree_node_black))
+ goto case6;
+
+ close_nephew = sibling->children[dir];
+
+ if (close_nephew != NULL &&
+ !vieter_tree_node_get(close_nephew, vieter_tree_node_black))
+ goto case5;
+
+case4:
+ vieter_tree_node_set(sibling, vieter_tree_node_black, false);
+ vieter_tree_node_set(parent, vieter_tree_node_black, true);
+
+ return out;
+
+case5:
+ vieter_tree_node_rotate(sibling, 1 - dir);
+ vieter_tree_node_set(sibling, vieter_tree_node_black, false);
+ vieter_tree_node_set(close_nephew, vieter_tree_node_black, true);
+ distant_nephew = sibling;
+ sibling = close_nephew;
+
+case6:
+ out = vieter_tree_node_rotate(parent, dir);
+ vieter_tree_node_set(sibling, vieter_tree_node_black,
+ vieter_tree_node_get(parent, vieter_tree_node_black));
+ vieter_tree_node_set(parent, vieter_tree_node_black, true);
+ vieter_tree_node_set(distant_nephew, vieter_tree_node_black, true);
+
+ return out;
+}
diff --git a/src/tree/vieter_tree_balancing.h b/src/tree/vieter_tree_balancing.h
new file mode 100644
index 0000000..e5dced0
--- /dev/null
+++ b/src/tree/vieter_tree_balancing.h
@@ -0,0 +1,46 @@
+#ifndef VIETER_TREE_BALANCING
+#define VIETER_TREE_BALANCING
+
+#include "vieter_tree_node.h"
+
+/*
+ * Check whether the given tree is a valid red-black tree.
+ *
+ * @param node root of the (sub)tree
+ * @param passed_black_nodes how many black nodes the recursion has already seen
+ * at this point. This should be initialized as 0 for the topmost call.
+ * @param expected_black_nodes the correct amount of black nodes to expect when
+ * a NULL child is encountered.
+ * @return true if the tree is valid, false otherwise
+ */
+bool vieter_tree_node_validate(vieter_tree_node *node,
+ uint64_t passed_black_nodes,
+ uint64_t expected_black_nodes);
+
+/*
+ * Balance a path of 3 nodes into a complete binary tree, with a red root and
+ * black children.
+ */
+vieter_tree_node *vieter_tree_node_balance(vieter_tree_node *node);
+
+/*
+ * Ensure the tree remains a valid red-black tree after having inserting the
+ * node.
+ */
+void vieter_tree_node_balance_after_insert(vieter_tree_node *node);
+
+/*
+ * Remove the given node, ensuring the tree remains a valid red-black tree.
+ *
+ * @param node node to remove. This should have at most a single child. If node
+ * isn't the root, this should be the right child, otherwise it can be either.
+ * @return root of the subtree that this function operated on. This can
+ * sometimes be the new root of the entire tree.
+ */
+vieter_tree_node *vieter_tree_node_remove_balanced(vieter_tree_node *node);
+
+/*
+ * Perform a tree rotation of the subtree with the given root.
+ */
+vieter_tree_node *vieter_tree_node_rotate(vieter_tree_node *old_root, bool dir);
+#endif
diff --git a/src/tree/vieter_tree_internal.h b/src/tree/vieter_tree_internal.h
new file mode 100644
index 0000000..1214572
--- /dev/null
+++ b/src/tree/vieter_tree_internal.h
@@ -0,0 +1,22 @@
+#include "vieter_tree.h"
+#include "vieter_tree_node.h"
+
+#include
+
+struct vieter_tree {
+ uint64_t size;
+ vieter_tree_node *root;
+};
+
+/*
+ * Inspect whether the tree is still a valid red-black-tree.
+ *
+ * @return true if valid, false otherwise.
+ */
+bool vieter_tree_validate(vieter_tree *tree);
+
+struct vieter_tree_iterator {
+ vieter_tree_node *current_node;
+ bool started;
+ bool done;
+};
diff --git a/src/tree/vieter_tree_iterator.c b/src/tree/vieter_tree_iterator.c
new file mode 100644
index 0000000..4eefe02
--- /dev/null
+++ b/src/tree/vieter_tree_iterator.c
@@ -0,0 +1,49 @@
+#include "vieter_tree.h"
+#include "vieter_tree_internal.h"
+
+vieter_tree_iterator *vieter_tree_iterator_from(vieter_tree *tree) {
+ vieter_tree_iterator *iter = calloc(1, sizeof(vieter_tree_iterator));
+
+ // An empty tree's iterator will be done immediately
+ if (tree->size == 0) {
+ iter->started = true;
+ iter->done = true;
+
+ return iter;
+ }
+
+ iter->current_node = tree->root;
+
+ return iter;
+}
+
+vieter_tree_error vieter_tree_iterator_next(void **out,
+ vieter_tree_iterator *iter) {
+ if (iter->done) {
+ return vieter_tree_iterator_done;
+ }
+
+ if (!iter->started) {
+ while (iter->current_node->children[0] != NULL) {
+ iter->current_node = iter->current_node->children[0];
+ }
+
+ iter->started = true;
+ }
+
+ *out = iter->current_node->data;
+
+ iter->current_node = vieter_tree_node_next(iter->current_node);
+
+ if (iter->current_node == NULL) {
+ iter->done = true;
+ }
+
+ return vieter_tree_ok;
+}
+
+void vieter_tree_iterator_free(vieter_tree_iterator **ptp) {
+ free(*ptp);
+
+ *ptp = NULL;
+}
diff --git a/src/tree/vieter_tree_node.c b/src/tree/vieter_tree_node.c
new file mode 100644
index 0000000..0a8e658
--- /dev/null
+++ b/src/tree/vieter_tree_node.c
@@ -0,0 +1,171 @@
+#include "vieter_tree_node.h"
+#include "vieter_tree_balancing.h"
+
+#include
+
+vieter_tree_node *vieter_tree_node_init() {
+ return calloc(1, sizeof(vieter_tree_node));
+}
+
+void vieter_tree_node_free(vieter_tree_node *node) { free(node); }
+
+void vieter_tree_node_add_child(vieter_tree_node *parent, uint64_t key,
+ vieter_tree_node *child) {
+ if (parent == NULL) {
+ return;
+ }
+
+ bool side = key > parent->key;
+ parent->children[side] = child;
+
+ if (child != NULL) {
+ child->parent = parent;
+ vieter_tree_node_set(child, vieter_tree_node_right, side);
+ }
+}
+
+void vieter_tree_node_set_children(vieter_tree_node *parent,
+ vieter_tree_node **children) {
+ memcpy(parent->children, children, 2 * sizeof(vieter_tree_node *));
+
+ for (uint8_t i = 0; i < 2; i++) {
+ if (parent->children[i] != NULL) {
+ parent->children[i]->parent = parent;
+ vieter_tree_node_set(parent->children[i], vieter_tree_node_right, i);
+ }
+ }
+}
+
+void vieter_tree_node_set_child(vieter_tree_node *parent,
+ vieter_tree_node *child, bool right) {
+ parent->children[right] = child;
+
+ if (child != NULL) {
+ child->parent = parent;
+ vieter_tree_node_set(child, vieter_tree_node_right, right);
+ }
+}
+
+vieter_tree_error vieter_tree_node_insert(vieter_tree_node *root, uint64_t key,
+ void *data) {
+ vieter_tree_node *node = root;
+ vieter_tree_node *parent = root;
+
+ while (node != NULL) {
+ if (node->key == key) {
+ return vieter_tree_already_present;
+ }
+
+ parent = node;
+ node = node->children[key > parent->key];
+ }
+
+ vieter_tree_node *new_node = vieter_tree_node_init();
+ new_node->key = key;
+ new_node->data = data;
+
+ vieter_tree_node_add_child(parent, key, new_node);
+ vieter_tree_node_balance_after_insert(new_node);
+
+ return vieter_tree_ok;
+}
+
+vieter_tree_error vieter_tree_node_search_node(vieter_tree_node **out,
+ vieter_tree_node *root,
+ uint64_t key) {
+ vieter_tree_node *node = root;
+
+ while (node != NULL) {
+ if (node->key == key) {
+ *out = node;
+
+ return vieter_tree_ok;
+ }
+
+ node = node->children[key > node->key];
+ }
+
+ return vieter_tree_not_present;
+}
+
+vieter_tree_error vieter_tree_node_search(void **out, vieter_tree_node *root,
+ uint64_t key) {
+ vieter_tree_node *target;
+ vieter_tree_error res = vieter_tree_node_search_node(&target, root, key);
+
+ if (res != vieter_tree_ok) {
+ return res;
+ }
+
+ *out = target->data;
+
+ return vieter_tree_ok;
+}
+
+vieter_tree_error
+vieter_tree_node_remove(void **out, vieter_tree_node **root_ptr, uint64_t key) {
+ vieter_tree_node *target;
+ vieter_tree_error res = vieter_tree_node_search_node(&target, *root_ptr, key);
+
+ if (res != vieter_tree_ok) {
+ return res;
+ }
+
+ *out = target->data;
+ vieter_tree_node *possible_new_root;
+
+ if (target->children[0] != NULL && target->children[1] != NULL) {
+ vieter_tree_node *replacement = target->children[1];
+
+ while (replacement->children[0] != NULL) {
+ replacement = replacement->children[0];
+ }
+
+ target->key = replacement->key;
+ target->data = replacement->data;
+
+ possible_new_root = vieter_tree_node_remove_balanced(replacement);
+ } else {
+ possible_new_root = vieter_tree_node_remove_balanced(target);
+ }
+
+ if (possible_new_root == NULL) {
+ *root_ptr = NULL;
+ } else if (possible_new_root->parent == NULL) {
+ *root_ptr = possible_new_root;
+ }
+
+ return vieter_tree_ok;
+}
+
+void vieter_tree_node_set(vieter_tree_node *node, vieter_tree_node_flag flag,
+ bool set) {
+ if (set) {
+ node->flags |= flag;
+ } else {
+ node->flags &= ~flag;
+ }
+}
+
+bool vieter_tree_node_get(vieter_tree_node *node, vieter_tree_node_flag flag) {
+ return (node->flags & flag) != 0;
+}
+
+vieter_tree_node *vieter_tree_node_next(vieter_tree_node *node) {
+ if (node->children[1] != NULL) {
+ node = node->children[1];
+
+ while (node->children[0] != NULL) {
+ node = node->children[0];
+ }
+
+ return node;
+ }
+
+ while (node->parent != NULL &&
+ vieter_tree_node_get(node, vieter_tree_node_right)) {
+ node = node->parent;
+ }
+
+ return node->parent;
+}
diff --git a/src/tree/vieter_tree_node.h b/src/tree/vieter_tree_node.h
new file mode 100644
index 0000000..4db3cfe
--- /dev/null
+++ b/src/tree/vieter_tree_node.h
@@ -0,0 +1,94 @@
+#ifndef VIETER_TREE_NODE
+#define VIETER_TREE_NODE
+
+#include "vieter_tree.h"
+#include
+#include
+
+typedef enum vieter_tree_node_flag {
+ vieter_tree_node_black = ((uint8_t)1) << 0,
+ // This flag is used to index the children array. If this flag isn't set,
+ // it'll evaluate to false, or index 0 in the children array.
+ vieter_tree_node_right = ((uint8_t)1) << 1
+} vieter_tree_node_flag;
+
+typedef struct vieter_tree_node {
+ uint64_t key;
+ void *data;
+ struct vieter_tree_node *parent;
+ struct vieter_tree_node *children[2];
+ uint8_t flags;
+} vieter_tree_node;
+
+/*
+ * Allocate a new node.
+ */
+vieter_tree_node *vieter_tree_node_init();
+
+/*
+ * Free an allocated node.
+ */
+void vieter_tree_node_free(vieter_tree_node *node);
+
+/*
+ * Insert a new key into the given tree.
+ */
+vieter_tree_error vieter_tree_node_insert(vieter_tree_node *root, uint64_t key,
+ void *data);
+
+/*
+ * Return the node representing the requested value.
+ */
+vieter_tree_error vieter_tree_node_search_node(vieter_tree_node **out,
+ vieter_tree_node *root,
+ uint64_t key);
+
+/*
+ * Search for the data represented by the given key.
+ */
+vieter_tree_error vieter_tree_node_search(void **out, vieter_tree_node *root,
+ uint64_t key);
+
+/*
+ * Remove the data associated with the given key.
+ */
+vieter_tree_error
+vieter_tree_node_remove(void **out, vieter_tree_node **root_ptr, uint64_t key);
+
+/*
+ * Set a node's bit flag to the given value.
+ */
+void vieter_tree_node_set(vieter_tree_node *node, vieter_tree_node_flag flag,
+ bool value);
+
+/*
+ * Get whether a node's bit flag is set.
+ */
+bool vieter_tree_node_get(vieter_tree_node *node, vieter_tree_node_flag flag);
+
+/*
+ * Add a new child to the parent, replacing either its left or right child,
+ * depending on the key values.
+ */
+void vieter_tree_node_add_child(vieter_tree_node *parent, uint64_t key,
+ vieter_tree_node *child);
+
+/*
+ * Replace a node's children array.
+ */
+void vieter_tree_node_set_children(vieter_tree_node *parent,
+ vieter_tree_node **children);
+
+/*
+ * Set a node's left or right child to the given node.
+ */
+void vieter_tree_node_set_child(vieter_tree_node *parent,
+ vieter_tree_node *child, bool right);
+
+/*
+ * Return the in-order successor of the given node, or NULL if it's the last
+ * node in the tree.
+ */
+vieter_tree_node *vieter_tree_node_next(vieter_tree_node *node);
+
+#endif
diff --git a/test/cron/test_parse.c b/test/cron/test_parse.c
index 030c720..6417c40 100644
--- a/test/cron/test_parse.c
+++ b/test/cron/test_parse.c
@@ -1,7 +1,7 @@
#include "acutest.h"
#include "vieter_cron.h"
-void test_not_allowed() {
+void test_illegal_expressions() {
char *expressions[] = {
"4 *-7",
"4 *-7/4",
@@ -33,6 +33,6 @@ void test_not_allowed() {
}
TEST_LIST = {
- {"not_allowed", test_not_allowed},
+ {"cron illegal expressions", test_illegal_expressions},
{NULL, NULL}
};
diff --git a/test/cron/test_parse_part.c b/test/cron/test_parse_part.c
new file mode 100644
index 0000000..5c9c10e
--- /dev/null
+++ b/test/cron/test_parse_part.c
@@ -0,0 +1,43 @@
+#include "acutest.h"
+#include "vieter_cron_parse.h"
+
+struct parse_test {
+ char *part;
+ uint8_t min;
+ uint8_t max;
+};
+
+void test_illegal_parts() {
+ struct parse_test parts[] = {
+ { "*-7", 0, 23 },
+ { "*-7/4", 0, 23 },
+ { "7/*", 0, 23 },
+ { "/5", 0, 23 },
+ { "4~6", 0, 23 },
+ { "5/2-5", 0, 23 },
+ { "1/2/3", 0, 23 },
+ { "*5", 0, 59 },
+ { "x", 0, 59 },
+ { NULL, 0, 0 }
+ };
+
+ int i = 0;
+ uint64_t out;
+ char *s;
+
+ while (parts[i].part != NULL) {
+ // Function modifies string in-place
+ s = strdup(parts[i].part);
+
+ TEST_CHECK_(vieter_cron_expr_parse_part(&out, s, parts[i].min, parts[i].max) != vieter_cron_parse_ok, "%s (%i - %i)", parts[i].part, parts[i].min, parts[i].max);
+
+ free(s);
+
+ i++;
+ }
+}
+
+TEST_LIST = {
+ {"cron illegal parts", test_illegal_parts},
+ {NULL, NULL}
+};
diff --git a/test/heap/test_heap.c b/test/heap/test_heap.c
index f77b0dc..31ea354 100644
--- a/test/heap/test_heap.c
+++ b/test/heap/test_heap.c
@@ -178,10 +178,10 @@ void test_pop_random() {
}
TEST_LIST = {
- {"init", test_init},
- {"insert", test_insert},
- {"insert random", test_insert_random},
- {"pop", test_pop},
- {"pop random", test_pop_random},
+ {"heap init", test_init},
+ {"heap insert", test_insert},
+ {"heap insert random", test_insert_random},
+ {"heap pop", test_pop},
+ {"heap pop random", test_pop_random},
{NULL, NULL}
};
diff --git a/test/heap/test_merge.c b/test/heap/test_merge.c
index 10053f2..f0861fe 100644
--- a/test/heap/test_merge.c
+++ b/test/heap/test_merge.c
@@ -23,6 +23,6 @@ void test_merge_same_order() {
}
TEST_LIST = {
- {"merge same order", test_merge_same_order},
+ {"heap merge same order", test_merge_same_order},
{NULL, NULL}
};
diff --git a/test/tree/test_balancing.c b/test/tree/test_balancing.c
new file mode 100644
index 0000000..bdcd846
--- /dev/null
+++ b/test/tree/test_balancing.c
@@ -0,0 +1,71 @@
+#include "acutest.h"
+#include "vieter_tree_internal.h"
+#include "vieter_tree_node.h"
+#include "vieter_tree_balancing.h"
+
+// This uses the examples from wikipedia
+// https://en.wikipedia.org/wiki/Tree_rotation
+
+void test_rotate_right() {
+ vieter_tree_node *a = vieter_tree_node_init();
+ vieter_tree_node *b = vieter_tree_node_init();
+ vieter_tree_node *p = vieter_tree_node_init();
+
+ vieter_tree_node_set_child(p, a, false);
+ vieter_tree_node_set_child(p, b, true);
+
+ vieter_tree_node *c = vieter_tree_node_init();
+ vieter_tree_node *q = vieter_tree_node_init();
+
+ vieter_tree_node_set_child(q, p, false);
+ vieter_tree_node_set_child(q, c, true);
+
+ vieter_tree_node *new_root = vieter_tree_node_rotate(q, true);
+
+ TEST_CHECK(new_root == p);
+ TEST_CHECK(new_root->children[0] == a);
+ TEST_CHECK(new_root->children[1] == q);
+ TEST_CHECK(new_root->children[1]->children[0] == b);
+ TEST_CHECK(new_root->children[1]->children[1] == c);
+
+ vieter_tree_node_free(a);
+ vieter_tree_node_free(b);
+ vieter_tree_node_free(p);
+ vieter_tree_node_free(c);
+ vieter_tree_node_free(q);
+}
+
+void test_rotate_left() {
+ vieter_tree_node *b = vieter_tree_node_init();
+ vieter_tree_node *c = vieter_tree_node_init();
+ vieter_tree_node *q = vieter_tree_node_init();
+
+ vieter_tree_node_set_child(q, b, false);
+ vieter_tree_node_set_child(q, c, true);
+
+ vieter_tree_node *a = vieter_tree_node_init();
+ vieter_tree_node *p = vieter_tree_node_init();
+
+ vieter_tree_node_set_child(p, a, false);
+ vieter_tree_node_set_child(p, q, true);
+
+ vieter_tree_node *new_root = vieter_tree_node_rotate(p, false);
+
+ TEST_CHECK(new_root == q);
+ TEST_CHECK(new_root->children[0] == p);
+ TEST_CHECK(new_root->children[1] == c);
+ TEST_CHECK(new_root->children[0]->children[0] == a);
+ TEST_CHECK(new_root->children[0]->children[1] == b);
+
+ vieter_tree_node_free(a);
+ vieter_tree_node_free(b);
+ vieter_tree_node_free(p);
+ vieter_tree_node_free(c);
+ vieter_tree_node_free(q);
+}
+
+TEST_LIST = {
+ {"tree rotate right", test_rotate_right},
+ {"tree rotate left", test_rotate_left},
+ {NULL, NULL}
+};
diff --git a/test/tree/test_tree.c b/test/tree/test_tree.c
new file mode 100644
index 0000000..10235cb
--- /dev/null
+++ b/test/tree/test_tree.c
@@ -0,0 +1,72 @@
+#include "acutest.h"
+#include "vieter_tree_internal.h"
+
+#define TEST_SIZE(tree, size) \
+ TEST_CHECK(vieter_tree_size(tree) == size); \
+ TEST_MSG("Size: %zu", vieter_tree_size(tree))
+
+void test_init() {
+ vieter_tree *tree = vieter_tree_init();
+ TEST_CHECK(tree != NULL);
+ TEST_SIZE(tree, 0);
+ vieter_tree_free(tree);
+}
+
+void test_insert() {
+ vieter_tree *tree = vieter_tree_init();
+
+ for (uint64_t i = 0; i < 250; i++) {
+ TEST_CHECK(vieter_tree_insert(tree, i, (void *)i) == vieter_tree_ok);
+ TEST_SIZE(tree, i + 1);
+ TEST_CHECK(vieter_tree_validate(tree));
+ }
+
+ vieter_tree_iterator *iter = vieter_tree_iterator_from(tree);
+
+ void *out = NULL;
+
+ for (uint64_t i = 0; i < 250; i++) {
+ TEST_CHECK(vieter_tree_search(&out, tree, i) == vieter_tree_ok);
+ TEST_CHECK(out == (void *)i);
+ TEST_CHECK(vieter_tree_insert(tree, i, NULL) == vieter_tree_already_present);
+ TEST_CHECK(vieter_tree_search(&out, tree, i) == vieter_tree_ok);
+
+ out = NULL;
+
+ TEST_CHECK(vieter_tree_iterator_next(&out, iter) == vieter_tree_ok);
+ TEST_CHECK(out == (void *)i);
+ }
+
+ TEST_CHECK(vieter_tree_iterator_next(&out, iter) == vieter_tree_iterator_done);
+
+ vieter_tree_iterator_free(&iter);
+ vieter_tree_free(tree);
+}
+
+void test_remove() {
+ vieter_tree *tree = vieter_tree_init();
+
+ for (uint64_t i = 0; i < 250; i++) {
+ TEST_CHECK(vieter_tree_insert(tree, i, NULL) == vieter_tree_ok);
+ TEST_CHECK(vieter_tree_validate(tree));
+ }
+
+ void *out;
+
+ for (uint64_t i = 0; i < 250; i++) {
+ TEST_CHECK(vieter_tree_search(&out, tree, i) == vieter_tree_ok);
+ TEST_CHECK(vieter_tree_remove(&out, tree, i) == vieter_tree_ok);
+ TEST_CHECK(vieter_tree_validate(tree));
+ TEST_CHECK(vieter_tree_search(&out, tree, i) == vieter_tree_not_present);
+ TEST_SIZE(tree, 250 - i - 1);
+ }
+
+ vieter_tree_free(tree);
+}
+
+TEST_LIST = {
+ {"tree init", test_init},
+ {"tree insert", test_insert},
+ {"tree remove", test_remove},
+ {NULL, NULL}
+};
diff --git a/test/tree/test_tree_random.c b/test/tree/test_tree_random.c
new file mode 100644
index 0000000..d1b9ab0
--- /dev/null
+++ b/test/tree/test_tree_random.c
@@ -0,0 +1,59 @@
+#include "acutest.h"
+#include "vieter_tree_internal.h"
+
+#define TEST_SIZE(tree, size) \
+ TEST_CHECK(vieter_tree_size(tree) == size); \
+ TEST_MSG("Size: %zu", vieter_tree_size(tree))
+
+int uint64_t_compare(const void *a, const void *b) {
+ if ((*(uint64_t *)a) < (*(uint64_t *)b)) {
+ return -1;
+ } else if ((*(uint64_t *)a) > (*(uint64_t *)b)) {
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+void test_insert_random() {
+ const uint64_t n = 1000;
+ srand(0);
+
+ vieter_tree *tree = vieter_tree_init();
+
+ uint64_t *numbers = malloc(n * sizeof(uint64_t));
+ uint64_t num;
+ void *out = NULL;
+
+ for (uint64_t i = 0; i < n; i++) {
+ num = rand();
+ vieter_tree_insert(tree, num, (void *)num);
+ TEST_SIZE(tree, i + 1);
+ TEST_CHECK(vieter_tree_validate(tree));
+ TEST_CHECK(vieter_tree_search(&out, tree, num) == vieter_tree_ok);
+ TEST_CHECK(out == (void *)num);
+
+ out = NULL;
+
+ numbers[i] = num;
+ }
+
+ qsort(numbers, n, sizeof(uint64_t), uint64_t_compare);
+
+ vieter_tree_iterator *iter = vieter_tree_iterator_from(tree);
+ out = NULL;
+
+ for (uint64_t i = 0; i < n; i++) {
+ TEST_CHECK(vieter_tree_iterator_next(&out, iter) == vieter_tree_ok);
+ TEST_CHECK(out == (void *)numbers[i]);
+ }
+
+ free(numbers);
+ vieter_tree_iterator_free(&iter);
+ vieter_tree_free(tree);
+}
+
+TEST_LIST = {
+ {"tree insert random", test_insert_random},
+ {NULL, NULL}
+};