1 files changed, 87 insertions, 0 deletions
diff --git a/src/common/db.hpp b/src/common/db.hpp
new file mode 100644
index 0000000..145ba13
--- /dev/null
+++ b/src/common/db.hpp
@@ -0,0 +1,87 @@
+// WARNING: there is a system header by this name
+#ifndef DB_HPP
+#define DB_HPP
+# include "sanity.hpp"
+
+# include <stdarg.h>
+
+/// Number of tree roots
+// Somewhat arbitrary - larger wastes more space but is faster for large trees
+// num % HASH_SIZE minimize collisions even for similar num
+# define HASH_SIZE (256+27)
+
+typedef enum dbn_color
+{
+    RED,
+    BLACK
+} dbn_color;
+
+typedef intptr_t numdb_key_t;
+typedef union db_key_t
+{
+    char *ms __attribute__((deprecated));
+    const char* s;
+    numdb_key_t i;
+} db_key_t;
+typedef void* db_val_t;
+typedef uint32_t hash_t;
+typedef void (*db_func_t)(db_key_t, db_val_t, va_list);
+
+/// DataBase Node
+struct dbn
+{
+    struct dbn *parent, *left, *right;
+    dbn_color color;
+    db_key_t key;
+    db_val_t data;
+};
+
+typedef enum dbt_type
+{
+    DB_NUMBER,
+    DB_STRING,
+} dbt_type;
+
+/// DataBase Table
+struct dbt
+{
+    dbt_type type;
+    /// Note, before replacement, key/values to be replaced
+    // TODO refactor to decrease/eliminate the uses of this?
+    void (*release) (db_key_t, db_val_t) __attribute__((deprecated));
+    /// Maximum length of a string key - TODO refactor to ensure all strings are NUL-terminated
+    size_t maxlen __attribute__((deprecated));
+    /// The root trees
+    struct dbn *ht[HASH_SIZE];
+};
+
+# define strdb_search(t,k)   db_search((t),(db_key_t)(k))
+# define strdb_insert(t,k,d) db_insert((t),(db_key_t)(k),(db_val_t)(d))
+# define strdb_erase(t,k)    db_erase ((t),(db_key_t)(k))
+# define strdb_foreach       db_foreach
+# define strdb_final         db_final
+# define numdb_search(t,k)   db_search((t),(db_key_t)(k))
+# define numdb_insert(t,k,d) db_insert((t),(db_key_t)(k),(db_val_t)(d))
+# define numdb_erase(t,k)    db_erase ((t),(db_key_t)(k))
+# define numdb_foreach       db_foreach
+# define numdb_final         db_final
+
+/// Create a map from char* to void*, with strings possibly not null-terminated
+struct dbt *strdb_init (size_t maxlen);
+/// Create a map from int to void*
+struct dbt *numdb_init (void);
+/// Return the value corresponding to the key, or NULL if not found
+db_val_t db_search (struct dbt *table, db_key_t key);
+/// Add or replace table[key] = data
+// if it was already there, call release
+struct dbn *db_insert (struct dbt *table, db_key_t key, db_val_t data);
+/// Remove a key from the table, returning the data
+db_val_t db_erase (struct dbt *table, db_key_t key);
+
+/// Execute a function for every element, in unspecified order
+void db_foreach (struct dbt *, db_func_t, ...);
+// opposite of init? Calls release for every element and frees memory
+// This probably isn't really needed: we don't have to free memory while exiting
+void db_final (struct dbt *, db_func_t, ...) __attribute__((deprecated));
+
+#endif