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-rw-r--r--src/lib/queue.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/src/lib/queue.c b/src/lib/queue.c
new file mode 100644
index 0000000..1fc35f6
--- /dev/null
+++ b/src/lib/queue.c
@@ -0,0 +1,55 @@
+#include <lib/queue.h>
+
+void push_to_queue(struct Entry* e, struct Queue* q)
+{
+ q->end.next->next = e;
+ q->end.next = e;
+ e->next = &q->end;
+}
+
+void prepend_to_queue(struct Entry* e, struct Queue* q)
+{
+ e->next = q->start.next;
+ q->start.next = e;
+ if (e->next->entry_type == END_ENTRY)
+ q->end.next = e;
+}
+
+struct Entry* pop_from_queue(struct Queue* q)
+{
+ if (q->start.next->entry_type == END_ENTRY)
+ return 0;
+ struct Entry* e = q->start.next;
+ q->start.next = e->next;
+ if (e->next->entry_type == END_ENTRY)
+ q->end.next = &q->start;
+ return e;
+}
+
+struct Entry* remove_next_from_queue(struct Entry* e)
+{
+ struct Entry* prev = e;
+ struct Entry* remove = e->next;
+ struct Entry* next = remove->next;
+ if (remove->entry_type != VALUE_ENTRY)
+ return 0;
+ prev->next = next;
+ if (next->entry_type == END_ENTRY)
+ next->next = prev;
+ return remove;
+}
+
+struct Entry* find_value(void* value, struct Queue* q)
+{
+ struct Entry* prev;
+ struct Entry* entry;
+ prev = &q->start;
+ entry = prev->next;
+ while (entry->entry_type != END_ENTRY) {
+ if (entry->value == value)
+ return prev;
+ prev = entry;
+ entry = prev->next;
+ }
+ return 0;
+}