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

Makefile

@@ -39,8 +39,12 @@ objs: $(OBJS)
 libtrie:
 	$(MAKE) -C trie
 
+.PHONY: liblsm
+liblsm:
+	$(MAKE) -C lsm
+
 .PHONY: bin
-$(BIN): libtrie $(OBJS)
+$(BIN): libtrie liblsm $(OBJS)
 	$(CC) -o $@ $(OBJS) $(_LDFLAGS)
 
 $(BUILD_DIR)/$(SRC_DIR)/%.c.o: $(SRC_DIR)/%.c
@@ -104,6 +108,7 @@ fmt:
 clean:
 	rm -rf $(BUILD_DIR)
 	$(MAKE) -C trie clean
+	$(MAKE) -C lsm clean
 
 
 .PHONY: bear

config.mk

@@ -7,9 +7,9 @@ SRC_DIR        = src
 TEST_DIR       = test
 THIRDPARTY_DIR = thirdparty
 
-INC_DIRS  = include $(THIRDPARTY_DIR)/include trie/include
-LIBS      = trie m
-LIB_DIRS  = ./trie/build
+INC_DIRS  = include $(THIRDPARTY_DIR)/include trie/include lsm/include
+LIBS      = trie m lsm
+LIB_DIRS  = ./trie/build  ./lsm/build
 
 # -MMD: generate a .d file for every source file. This file can be imported by
 #  make and makes make aware that a header file has been changed, ensuring an

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

lsm/src/_include/lsm/store_internal.h

@@ -1,6 +1,8 @@
 #ifndef LSM_STORE_INTERNAL
 #define LSM_STORE_INTERNAL
 
+#include <stdio.h>
+
 #include "lsm/store.h"
 #include "lsm/str_internal.h"
 #include "lsm/trie.h"
@@ -11,17 +13,26 @@ typedef struct lsm_attr {
 } lsm_attr;
 
 struct lsm_entry {
-  lsm_str key;
+  lsm_str *key;
   struct {
     uint64_t count;
     uint64_t bitmap;
     lsm_attr *items;
   } attrs;
-  lsm_str data;
+  struct {
+    uint64_t len;
+    union {
+      FILE *file;
+      char *ptr;
+    } value;
+    bool on_disk;
+  } data;
 };
 
 struct lsm_store {
   lsm_trie *trie;
+  char *data_path;
+  char *db_path;
 };
 
 #endif

lsm/src/store/lsm_store.c

@@ -1,6 +1,81 @@
+#include <stdlib.h>
+#include <string.h>
+
+#include "lsm.h"
 #include "lsm/store.h"
+#include "lsm/trie.h"
 #include "lsm/store_internal.h"
 
-/* lsm_error lsm_store_init(lsm_store **ptr) { */
-/*   lsm_store *store = */
-/* } */
+lsm_error lsm_store_init(lsm_store **ptr) {
+  lsm_store *store = calloc(1, sizeof(lsm_store));
+
+  if (store == NULL) {
+    return lsm_error_failed_alloc;
+  }
+
+  lsm_error res = lsm_trie_init(&store->trie);
+
+  if (res != lsm_error_ok) {
+    free(store);
+
+    return res;
+  }
+
+  *ptr = store;
+
+  return lsm_error_ok;
+}
+
+lsm_error lsm_store_open(lsm_store **ptr, char *db_path, char *data_path) {
+  lsm_store *store;
+  LSM_RES(lsm_store_init(&store));
+
+  // TODO implement all of reading the db file
+
+  store->db_path = db_path;
+  store->data_path = data_path;
+
+  *ptr = store;
+
+  return lsm_error_ok;
+}
+
+lsm_error lsm_store_search(lsm_entry **out, lsm_store *store, lsm_str *key) {
+  return lsm_trie_search((void **)out, store->trie, key);
+}
+
+lsm_error lsm_store_insert(lsm_entry **out, lsm_store *store, lsm_str *key) {
+  lsm_entry *entry;
+
+  LSM_RES(lsm_entry_init(&entry));
+  LSM_RES(lsm_trie_insert(store->trie, key, entry));
+
+  entry->key = key;
+  *out = entry;
+
+  return lsm_error_ok;
+}
+
+lsm_error lsm_store_data_append(lsm_store *store, lsm_entry *entry, lsm_str *data) {
+  uint64_t new_len = entry->data.len + lsm_str_len(data);
+
+  // Data is in memory and still fits -> keep it in memory
+  if ((new_len <= LSM_STORE_DISK_THRESHOLD) && (!entry->data.on_disk)) {
+    char *buf = realloc(entry->data.value.ptr, new_len * sizeof(char));
+
+    if (buf == NULL) {
+      return lsm_error_failed_alloc;
+    }
+
+    memcpy(&buf[entry->data.len], lsm_str_ptr(data), lsm_str_len(data));
+    entry->data.value.ptr = buf;
+    entry->data.len = new_len;
+  }
+  // Data will end up on disk
+  else {
+    // Data is not yet on disk, so we create the file
+    if (!entry->data.on_disk) {
+
+    }
+  }
+}

lsm/src/store/lsm_store_entry.c

@@ -27,15 +27,15 @@ lsm_error lsm_entry_attr_get(lsm_str **out, lsm_entry *entry,
     return lsm_error_not_found;
   }
 
-  for (uint64_t i = 0; i < entry->attrs.count; i++) {
-    if (entry->attrs.items[i].type == type) {
-      *out = entry->attrs.items[i].str;
+  uint64_t i = 0;
 
-      return lsm_error_ok;
-    }
+  while (entry->attrs.items[i].type != type) {
+    i++;
   }
 
-  return lsm_error_not_found;
+  *out = entry->attrs.items[i].str;
+
+  return lsm_error_ok;
 }
 
 lsm_error lsm_entry_attr_remove(lsm_str **out, lsm_entry *entry,

lsm/src/str/lsm_str.c

@@ -196,3 +196,40 @@ bool lsm_str_eq(lsm_str *s1, lsm_str *s2) {
 
   return memcmp(lsm_str_ptr(s1), lsm_str_ptr(s2), s1->len) == 0;
 }
+
+lsm_error lsm_str_append(lsm_str *s, lsm_str *s2) {
+  if (s2->len == 0) {
+    return lsm_error_ok;
+  }
+
+  uint64_t new_len = s->len + s2->len;
+
+  if (new_len <= 8) {
+    memcpy(&s->data.val[s->len], s2->data.val, s2->len);
+  } else {
+    char *buf;
+
+    if (s->len <= 8) {
+      buf = malloc(new_len * sizeof(char));
+
+      if (buf == NULL) {
+        return lsm_error_failed_alloc;
+      }
+
+      memcpy(buf, s->data.val, s->len);
+    } else {
+      buf = realloc(s->data.ptr, new_len * sizeof(char));
+
+      if (buf == NULL) {
+        return lsm_error_failed_alloc;
+      }
+    }
+
+    memcpy(&buf[s->len], lsm_str_ptr(s2), s2->len);
+    s->data.ptr = buf;
+  }
+
+  s->len += s2->len;
+
+  return lsm_error_ok;
+}