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diff --git a/endless/gvdb/gvdb-builder.c b/endless/gvdb/gvdb-builder.c
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+/*
+ * Copyright © 2010 Codethink Limited
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the licence, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ *
+ * Author: Allison Lortie <desrt@desrt.ca>
+ */
+
+#include "gvdb-builder.h"
+#include "gvdb-format.h"
+
+#include <glib.h>
+#include <fcntl.h>
+#if !defined(G_OS_WIN32) || !defined(_MSC_VER)
+#include <unistd.h>
+#endif
+#include <string.h>
+
+
+struct _GvdbItem
+{
+ gchar *key;
+ guint32 hash_value;
+ guint32_le assigned_index;
+ GvdbItem *parent;
+ GvdbItem *sibling;
+ GvdbItem *next;
+
+ /* one of:
+ * this:
+ */
+ GVariant *value;
+
+ /* this: */
+ GHashTable *table;
+
+ /* or this: */
+ GvdbItem *child;
+};
+
+static void
+gvdb_item_free (gpointer data)
+{
+ GvdbItem *item = data;
+
+ g_free (item->key);
+
+ if (item->value)
+ g_variant_unref (item->value);
+
+ if (item->table)
+ g_hash_table_unref (item->table);
+
+ g_slice_free (GvdbItem, item);
+}
+
+GHashTable *
+gvdb_hash_table_new (GHashTable *parent,
+ const gchar *name_in_parent)
+{
+ GHashTable *table;
+
+ table = g_hash_table_new_full (g_str_hash, g_str_equal,
+ g_free, gvdb_item_free);
+
+ if (parent)
+ {
+ GvdbItem *item;
+
+ item = gvdb_hash_table_insert (parent, name_in_parent);
+ gvdb_item_set_hash_table (item, table);
+ }
+
+ return table;
+}
+
+static guint32
+djb_hash (const gchar *key)
+{
+ guint32 hash_value = 5381;
+
+ while (*key)
+ hash_value = hash_value * 33 + *(signed char *)key++;
+
+ return hash_value;
+}
+
+GvdbItem *
+gvdb_hash_table_insert (GHashTable *table,
+ const gchar *key)
+{
+ GvdbItem *item;
+
+ item = g_slice_new0 (GvdbItem);
+ item->key = g_strdup (key);
+ item->hash_value = djb_hash (key);
+
+ g_hash_table_insert (table, g_strdup (key), item);
+
+ return item;
+}
+
+void
+gvdb_hash_table_insert_string (GHashTable *table,
+ const gchar *key,
+ const gchar *value)
+{
+ GvdbItem *item;
+
+ item = gvdb_hash_table_insert (table, key);
+ gvdb_item_set_value (item, g_variant_new_string (value));
+}
+
+void
+gvdb_item_set_value (GvdbItem *item,
+ GVariant *value)
+{
+ g_return_if_fail (!item->value && !item->table && !item->child);
+
+ item->value = g_variant_ref_sink (value);
+}
+
+void
+gvdb_item_set_hash_table (GvdbItem *item,
+ GHashTable *table)
+{
+ g_return_if_fail (!item->value && !item->table && !item->child);
+
+ item->table = g_hash_table_ref (table);
+}
+
+void
+gvdb_item_set_parent (GvdbItem *item,
+ GvdbItem *parent)
+{
+ GvdbItem **node;
+
+ g_return_if_fail (g_str_has_prefix (item->key, parent->key));
+ g_return_if_fail (!parent->value && !parent->table);
+ g_return_if_fail (!item->parent && !item->sibling);
+
+ for (node = &parent->child; *node; node = &(*node)->sibling)
+ if (strcmp ((*node)->key, item->key) > 0)
+ break;
+
+ item->parent = parent;
+ item->sibling = *node;
+ *node = item;
+}
+
+typedef struct
+{
+ GvdbItem **buckets;
+ gint n_buckets;
+} HashTable;
+
+static HashTable *
+hash_table_new (gint n_buckets)
+{
+ HashTable *table;
+
+ table = g_slice_new (HashTable);
+ table->buckets = g_new0 (GvdbItem *, n_buckets);
+ table->n_buckets = n_buckets;
+
+ return table;
+}
+
+static void
+hash_table_free (HashTable *table)
+{
+ g_free (table->buckets);
+
+ g_slice_free (HashTable, table);
+}
+
+static void
+hash_table_insert (gpointer key,
+ gpointer value,
+ gpointer data)
+{
+ guint32 hash_value, bucket;
+ HashTable *table = data;
+ GvdbItem *item = value;
+
+ hash_value = djb_hash (key);
+ bucket = hash_value % table->n_buckets;
+ item->next = table->buckets[bucket];
+ table->buckets[bucket] = item;
+}
+
+static guint32_le
+item_to_index (GvdbItem *item)
+{
+ if (item != NULL)
+ return item->assigned_index;
+
+ return guint32_to_le (-1u);
+}
+
+typedef struct
+{
+ GQueue *chunks;
+ guint64 offset;
+ gboolean byteswap;
+} FileBuilder;
+
+typedef struct
+{
+ gsize offset;
+ gsize size;
+ gpointer data;
+} FileChunk;
+
+static gpointer
+file_builder_allocate (FileBuilder *fb,
+ guint alignment,
+ gsize size,
+ struct gvdb_pointer *pointer)
+{
+ FileChunk *chunk;
+
+ if (size == 0)
+ return NULL;
+
+ fb->offset += (-fb->offset) & (alignment - 1);
+ chunk = g_slice_new (FileChunk);
+ chunk->offset = fb->offset;
+ chunk->size = size;
+ chunk->data = g_malloc (size);
+
+ pointer->start = guint32_to_le (fb->offset);
+ fb->offset += size;
+ pointer->end = guint32_to_le (fb->offset);
+
+ g_queue_push_tail (fb->chunks, chunk);
+
+ return chunk->data;
+}
+
+static void
+file_builder_add_value (FileBuilder *fb,
+ GVariant *value,
+ struct gvdb_pointer *pointer)
+{
+ GVariant *variant, *normal;
+ gpointer data;
+ gsize size;
+
+ if (fb->byteswap)
+ {
+ value = g_variant_byteswap (value);
+ variant = g_variant_new_variant (value);
+ g_variant_unref (value);
+ }
+ else
+ variant = g_variant_new_variant (value);
+
+ normal = g_variant_get_normal_form (variant);
+ g_variant_unref (variant);
+
+ size = g_variant_get_size (normal);
+ data = file_builder_allocate (fb, 8, size, pointer);
+ g_variant_store (normal, data);
+ g_variant_unref (normal);
+}
+
+static void
+file_builder_add_string (FileBuilder *fb,
+ const gchar *string,
+ guint32_le *start,
+ guint16_le *size)
+{
+ FileChunk *chunk;
+ gsize length;
+
+ length = strlen (string);
+
+ chunk = g_slice_new (FileChunk);
+ chunk->offset = fb->offset;
+ chunk->size = length;
+ chunk->data = g_malloc (length);
+ if (length != 0)
+ memcpy (chunk->data, string, length);
+
+ *start = guint32_to_le (fb->offset);
+ *size = guint16_to_le (length);
+ fb->offset += length;
+
+ g_queue_push_tail (fb->chunks, chunk);
+}
+
+static void
+file_builder_allocate_for_hash (FileBuilder *fb,
+ gsize n_buckets,
+ gsize n_items,
+ guint bloom_shift,
+ gsize n_bloom_words,
+ guint32_le **bloom_filter,
+ guint32_le **hash_buckets,
+ struct gvdb_hash_item **hash_items,
+ struct gvdb_pointer *pointer)
+{
+ guint32_le bloom_hdr, table_hdr;
+ guchar *data;
+ gsize size;
+
+ g_assert (n_bloom_words < (1u << 27));
+
+ bloom_hdr = guint32_to_le (bloom_shift << 27 | n_bloom_words);
+ table_hdr = guint32_to_le (n_buckets);
+
+ size = sizeof bloom_hdr + sizeof table_hdr +
+ n_bloom_words * sizeof (guint32_le) +
+ n_buckets * sizeof (guint32_le) +
+ n_items * sizeof (struct gvdb_hash_item);
+
+ data = file_builder_allocate (fb, 4, size, pointer);
+
+#define chunk(s) (size -= (s), data += (s), data - (s))
+ memcpy (chunk (sizeof bloom_hdr), &bloom_hdr, sizeof bloom_hdr);
+ memcpy (chunk (sizeof table_hdr), &table_hdr, sizeof table_hdr);
+ *bloom_filter = (guint32_le *) chunk (n_bloom_words * sizeof (guint32_le));
+ *hash_buckets = (guint32_le *) chunk (n_buckets * sizeof (guint32_le));
+ *hash_items = (struct gvdb_hash_item *) chunk (n_items *
+ sizeof (struct gvdb_hash_item));
+ g_assert (size == 0);
+#undef chunk
+
+ memset (*bloom_filter, 0, n_bloom_words * sizeof (guint32_le));
+
+ /* NOTE - the code to actually fill in the bloom filter here is missing.
+ * Patches welcome!
+ *
+ * http://en.wikipedia.org/wiki/Bloom_filter
+ * http://0pointer.de/blog/projects/bloom.html
+ */
+}
+
+static void
+file_builder_add_hash (FileBuilder *fb,
+ GHashTable *table,
+ struct gvdb_pointer *pointer)
+{
+ guint32_le *buckets, *bloom_filter;
+ struct gvdb_hash_item *items;
+ HashTable *mytable;
+ GvdbItem *item;
+ guint32 index;
+ gint bucket;
+
+ mytable = hash_table_new (g_hash_table_size (table));
+ g_hash_table_foreach (table, hash_table_insert, mytable);
+ index = 0;
+
+ for (bucket = 0; bucket < mytable->n_buckets; bucket++)
+ for (item = mytable->buckets[bucket]; item; item = item->next)
+ item->assigned_index = guint32_to_le (index++);
+
+ file_builder_allocate_for_hash (fb, mytable->n_buckets, index, 5, 0,
+ &bloom_filter, &buckets, &items, pointer);
+
+ index = 0;
+ for (bucket = 0; bucket < mytable->n_buckets; bucket++)
+ {
+ buckets[bucket] = guint32_to_le (index);
+
+ for (item = mytable->buckets[bucket]; item; item = item->next)
+ {
+ struct gvdb_hash_item *entry = items++;
+ const gchar *basename;
+
+ g_assert (index == guint32_from_le (item->assigned_index));
+ entry->hash_value = guint32_to_le (item->hash_value);
+ entry->parent = item_to_index (item->parent);
+ entry->unused = 0;
+
+ if (item->parent != NULL)
+ basename = item->key + strlen (item->parent->key);
+ else
+ basename = item->key;
+
+ file_builder_add_string (fb, basename,
+ &entry->key_start,
+ &entry->key_size);
+
+ if (item->value != NULL)
+ {
+ g_assert (item->child == NULL && item->table == NULL);
+
+ file_builder_add_value (fb, item->value, &entry->value.pointer);
+ entry->type = 'v';
+ }
+
+ if (item->child != NULL)
+ {
+ guint32 children = 0, i = 0;
+ guint32_le *offsets;
+ GvdbItem *child;
+
+ g_assert (item->table == NULL);
+
+ for (child = item->child; child; child = child->sibling)
+ children++;
+
+ offsets = file_builder_allocate (fb, 4, 4 * children,
+ &entry->value.pointer);
+ entry->type = 'L';
+
+ for (child = item->child; child; child = child->sibling)
+ offsets[i++] = child->assigned_index;
+
+ g_assert (children == i);
+ }
+
+ if (item->table != NULL)
+ {
+ entry->type = 'H';
+ file_builder_add_hash (fb, item->table, &entry->value.pointer);
+ }
+
+ index++;
+ }
+ }
+
+ hash_table_free (mytable);
+}
+
+static FileBuilder *
+file_builder_new (gboolean byteswap)
+{
+ FileBuilder *builder;
+
+ builder = g_slice_new (FileBuilder);
+ builder->chunks = g_queue_new ();
+ builder->offset = sizeof (struct gvdb_header);
+ builder->byteswap = byteswap;
+
+ return builder;
+}
+
+static GString *
+file_builder_serialise (FileBuilder *fb,
+ struct gvdb_pointer root)
+{
+ struct gvdb_header header;
+ GString *result;
+
+ memset (&header, 0, sizeof (struct gvdb_header));
+
+ if (fb->byteswap)
+ {
+ header.signature[0] = GVDB_SWAPPED_SIGNATURE0;
+ header.signature[1] = GVDB_SWAPPED_SIGNATURE1;
+ }
+ else
+ {
+ header.signature[0] = GVDB_SIGNATURE0;
+ header.signature[1] = GVDB_SIGNATURE1;
+ }
+
+ result = g_string_new (NULL);
+
+ header.root = root;
+ g_string_append_len (result, (gpointer) &header, sizeof header);
+
+ while (!g_queue_is_empty (fb->chunks))
+ {
+ FileChunk *chunk = g_queue_pop_head (fb->chunks);
+
+ if (result->len != chunk->offset)
+ {
+ gchar zero[8] = { 0, };
+
+ g_assert (chunk->offset > result->len);
+ g_assert (chunk->offset - result->len < 8);
+
+ g_string_append_len (result, zero, chunk->offset - result->len);
+ g_assert (result->len == chunk->offset);
+ }
+
+ g_string_append_len (result, chunk->data, chunk->size);
+ g_free (chunk->data);
+
+ g_slice_free (FileChunk, chunk);
+ }
+
+ g_queue_free (fb->chunks);
+ g_slice_free (FileBuilder, fb);
+
+ return result;
+}
+
+GBytes *
+gvdb_table_write_bytes (GHashTable *table,
+ gboolean byteswap)
+{
+ struct gvdb_pointer root;
+ FileBuilder *fb;
+ GString *str;
+ GBytes *retval;
+
+ fb = file_builder_new (byteswap);
+ file_builder_add_hash (fb, table, &root);
+ str = file_builder_serialise (fb, root);
+
+ retval = g_bytes_new_take (str->str, str->len);
+ g_string_free (str, FALSE);
+
+ return retval;
+}
+
+gboolean
+gvdb_table_write_contents (GHashTable *table,
+ const gchar *filename,
+ gboolean byteswap,
+ GError **error)
+{
+ struct gvdb_pointer root;
+ gboolean status;
+ FileBuilder *fb;
+ GString *str;
+
+ fb = file_builder_new (byteswap);
+ file_builder_add_hash (fb, table, &root);
+ str = file_builder_serialise (fb, root);
+
+ status = g_file_set_contents (filename, str->str, str->len, error);
+ g_string_free (str, TRUE);
+
+ return status;
+}