feat(lsm): some more string functions; start of data streaming api

lsm/include/lsm.h

@@ -3,7 +3,12 @@
 
 #include <stdint.h>
 
-#define LSM_MAX_SKIP_SIZE 8
+#define LSM_RES(x) \
+  { \
+    lsm_error res = x; \
+    if (res != lsm_error_ok) \
+      return res; \
+  }
 
 typedef enum lsm_error {
   lsm_error_ok = 0,

lsm/include/lsm/store.h

@@ -7,6 +7,8 @@
 #include "lsm.h"
 #include "lsm/str.h"
 
+#define LSM_STORE_DISK_THRESHOLD 1024
+
 /**
  * The type of an entry attribute.
  *
@@ -73,7 +75,7 @@ lsm_error lsm_entry_attr_insert(lsm_entry *entry, lsm_attr_type type,
  * Remove an atribute from the given entry, if present.
  *
  * @param out pointer to store removed data pointer in. If NULL, data pointer
- * can get leaked.
+ * will be leaked.
  * @param entry entry to remove attribute from
  * @param type type of attribute to remove
  */
@@ -95,6 +97,15 @@ typedef struct lsm_store lsm_store;
  */
 lsm_error lsm_store_init(lsm_store **ptr);
 
+/**
+ * Open the given database file and load it into a new store object.
+ *
+ * @param ptr pointer to store newly allocated store
+ * @param db_path path to the database file
+ * @param data_path path to the data directory
+ */
+lsm_error lsm_store_open(lsm_store **ptr, char *db_path, char *data_path);
+
 /**
  * Dealocate an existing lsm_store object.
  *
@@ -102,4 +113,34 @@ lsm_error lsm_store_init(lsm_store **ptr);
  */
 void lsm_store_free(lsm_store *store);
 
+/**
+ * Search for an entry in the store.
+ *
+ * @param out pointer to store entry pointer in
+ * @param store store to search in
+ * @param key key to look with
+ */
+lsm_error lsm_store_search(lsm_entry **out, lsm_store *store, lsm_str *key);
+
+/**
+ * Allocate a new entry in the store with the specified key.
+ *
+ * @param out pointer to store new entry pointer in
+ * @param store store to modify
+ * @param key key to add; ownership of key pointer is taken over
+ */
+lsm_error lsm_store_insert(lsm_entry **out, lsm_store *store, lsm_str *key);
+
+/**
+ * Append new data to the given entry, which is expected to be in the store.
+ *
+ * This function will append either to disk or to memory, depending on the
+ * length of the entry's data.
+ *
+ * @param store store the entry is stored in
+ * @param entry entry to append data to
+ * @param data data to append
+ */
+lsm_error lsm_store_data_append(lsm_store *store, lsm_entry *entry, lsm_str *data);
+
 #endif

lsm/include/lsm/str.h

@@ -151,4 +151,12 @@ lsm_error lsm_str_truncate(lsm_str *s, uint64_t new_len);
  */
 lsm_error lsm_str_split(lsm_str *s, lsm_str *s2, uint64_t index);
 
+/**
+ * Append s2 to s. s2 is left untouched.
+ *
+ * @param s string to append s2 to
+ * @param s2 string to append to s
+ */
+lsm_error lsm_str_append(lsm_str *s, lsm_str *s2);
+
 #endif