chore(lsm): some refactoring

lsm/include/lsm.h

@@ -10,6 +10,15 @@
       return res;                                                              \
   }
 
+#define LSM_RES2(x, e)                                                         \
+  {                                                                            \
+    lsm_error res = x;                                                         \
+    if (res != lsm_error_ok) {                                                 \
+      e;                                                                       \
+      return res;                                                              \
+    }                                                                          \
+  }
+
 typedef enum lsm_error {
   lsm_error_ok = 0,
   lsm_error_failed_alloc = 1,

lsm/include/lsm/bt.h

@@ -37,7 +37,7 @@ uint64_t lsm_bt_size(const lsm_bt *bt);
  * @param bt binary tree to search
  * @param key key to search
  */
-lsm_error lsm_bt_search(void **out, lsm_bt *bt, char key);
+lsm_error lsm_bt_search(void **out, const lsm_bt *bt, char key);
 
 /**
  * Insert a new data value into the tree with the given key.

lsm/include/lsm/store.h

@@ -143,7 +143,7 @@ void lsm_store_free(lsm_store *store);
  * @param key key to search
  */
 lsm_error lsm_store_open_read(lsm_entry_handle **out, lsm_store *store,
-                              lsm_str *key);
+                              const lsm_str *key);
 
 /**
  * Open a write handle to the given entry. This handle should only be used for
@@ -155,7 +155,7 @@ lsm_error lsm_store_open_read(lsm_entry_handle **out, lsm_store *store,
  * @param key key to search
  */
 lsm_error lsm_store_open_write(lsm_entry_handle **out, lsm_store *store,
-                               lsm_str *key);
+                              const lsm_str *key);
 
 /**
  * Close an open entry handle.
@@ -193,7 +193,7 @@ void lsm_entry_remove(lsm_entry_handle *handle);
  * @param entry entry to append data to
  * @param data data to append
  */
-lsm_error lsm_entry_data_append(lsm_entry_handle *handle, lsm_str *data);
+lsm_error lsm_entry_data_append(lsm_entry_handle *handle, const lsm_str *data);
 
 /**
  * Same as `lsm_entry_data_append`, except that it takes a direct char array.

lsm/include/lsm/str.h

@@ -107,14 +107,14 @@ uint64_t lsm_str_len(const lsm_str *str);
  *
  * @param str string to return pointer for
  */
-const char *lsm_str_ptr(lsm_str *str);
+const char *lsm_str_ptr(const lsm_str *str);
 
 /**
  * Returns the character at the specified position.
  *
  * @index index of character to return
  */
-char lsm_str_char(lsm_str *str, uint64_t index);
+char lsm_str_char(const lsm_str *str, uint64_t index);
 
 /**
  * Take a substring and copy it to a provided string object.
@@ -127,7 +127,7 @@ char lsm_str_char(lsm_str *str, uint64_t index);
  * or equal to the string's length, out will be a zero-length string.
  * @param end exclusive end index for the substring
  */
-lsm_error lsm_str_substr(lsm_str *out, lsm_str *str, uint64_t start,
+lsm_error lsm_str_substr(lsm_str *out, const lsm_str *str, uint64_t start,
                          uint64_t end);
 
 /**
@@ -141,7 +141,7 @@ lsm_error lsm_str_substr(lsm_str *out, lsm_str *str, uint64_t start,
  * @param s2 string to compare s1 to
  * @param s2_offset offset inside s2 to start comparing from
  */
-uint64_t lsm_str_cmp(lsm_str *s1, uint64_t s1_offset, lsm_str *s2,
+uint64_t lsm_str_cmp(const lsm_str *s1, uint64_t s1_offset, const lsm_str *s2,
                      uint64_t s2_offset);
 
 /**
@@ -151,7 +151,7 @@ uint64_t lsm_str_cmp(lsm_str *s1, uint64_t s1_offset, lsm_str *s2,
  * @param s2 second string to compare
  * @return true if their values are equal, false otherwise
  */
-bool lsm_str_eq(lsm_str *s1, lsm_str *s2);
+bool lsm_str_eq(const lsm_str *s1, const lsm_str *s2);
 
 /**
  * Truncate an already initialized string in-place.

lsm/include/lsm/trie.h

@@ -30,16 +30,16 @@ void lsm_trie_free(lsm_trie *trie);
  * @param key key to insert data with
  * @param data data to insert
  */
-lsm_error lsm_trie_insert(lsm_trie *trie, lsm_str *key, void *data);
+lsm_error lsm_trie_insert(lsm_trie *trie, const lsm_str *key, void *data);
 
 /**
  * Search for an element in the trie.
  *
- * @param out where to store data opinter, if present
+ * @param out where to store data pointer, if present
  * @param trie trie to search in
  * @param key key to search with
  */
-lsm_error lsm_trie_search(void **data, lsm_trie *trie, lsm_str *key);
+lsm_error lsm_trie_search(void **out, const lsm_trie *trie, const lsm_str *key);
 
 /**
  * Remove an element from the trie.
@@ -48,7 +48,7 @@ lsm_error lsm_trie_search(void **data, lsm_trie *trie, lsm_str *key);
  * @param trie trie to remove from
  * @param key key to remove
  */
-lsm_error lsm_trie_remove(void **data, lsm_trie *trie, lsm_str *key);
+lsm_error lsm_trie_remove(void **out, lsm_trie *trie, const lsm_str *key);
 
 /**
  * Return the size of a trie