osl-0.2.0.

[osl.git] / osl_core.h

diff --git a/osl_core.h b/osl_core.h
index 858743aae308c236d242586abdcf6ac50e99ee0e..e98c33538bfff043b2ae94145e9dee2b836f28bc 100644 (file)
--- a/osl_core.h
+++ b/osl_core.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2007-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2007-2009 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -9,7 +9,7 @@
 #include "rbtree.h"
 #include "hash.h"
 
-static __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...);
+__must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...);
 
 /** Internal representation of a column of an osl table. */
 struct osl_column {
@@ -38,6 +38,13 @@ struct osl_column {
 struct osl_table {
        /** Pointer to the table description */
        const struct osl_table_description *desc;
+       /**
+        * The CURRENT_TABLE_VERSION value of the library which created the
+        * table. This value is stored in the index header at table creation
+        * time. When the table is opened, the field is initialized from the
+        * on-disk value.
+        */
+       uint8_t version;
        /** The size of the index header of this table. */
        uint16_t index_header_size;
        /** Contains the mapping of the table's index file */
@@ -83,7 +90,6 @@ int init_table_structure(const struct osl_table_description *desc,
 int row_is_invalid(struct osl_table *t, uint32_t row_num);
 int get_mapped_object(const struct osl_table *t, unsigned col_num,
        uint32_t row_num, struct osl_object *obj);
-int para_truncate(const char *filename, off_t size);
 int unmap_table(struct osl_table *t, enum osl_close_flags flags);
 int init_rbtrees(struct osl_table *t);
 
@@ -134,7 +140,7 @@ _static_inline_ struct osl_column_description *get_column_description(
  */
 enum index_header_offsets {
        /** Bytes 0-8: PARASLASH. */
-       IDX_PARA_MAGIC = 0,
+       IDX_OSL_MAGIC = 0,
        /** Byte 9: Dirty flag (nonzero if table is mapped). */
        IDX_DIRTY_FLAG = 9,
        /** Byte 10: osl table version number. */
@@ -166,7 +172,7 @@ enum index_column_desc_offsets {
 };
 
 /** Magic string contained in the header of the index file of each osl table. */
-#define PARA_MAGIC "PARASLASH"
+#define OSL_MAGIC "PARASLASH"
 
 /**
  * The minimal number of bytes for a column in the index header.
@@ -191,9 +197,20 @@ _static_inline_ size_t index_column_description_size(const char *name)
        return MIN_IDX_COLUMN_DESCRIPTION_SIZE + strlen(name) - 1;
 }
 
-#define CURRENT_TABLE_VERSION 1
+/*
+ * The version used by this instance of the library. Written to the index of
+ * newly created tables.
+ */
+#define CURRENT_TABLE_VERSION 3
+
+/*
+ * The lowest table version this library understands. On open, if
+ * current_version(table) < min_version(lib) the osl_open_table() call
+ * fails.
+ */
 #define MIN_TABLE_VERSION 1
-#define MAX_TABLE_VERSION 1
+
+
 /** An index header must be at least that many bytes long. */
 #define MIN_INDEX_HEADER_SIZE(num_cols) (MIN_IDX_COLUMN_DESCRIPTION_SIZE \
        * num_cols + IDX_COLUMN_DESCRIPTIONS)
@@ -304,8 +321,8 @@ _static_inline_ int get_cell_index(const struct osl_table *t, uint32_t row_num,
 _static_inline_ void update_cell_index(char *row_index, struct osl_column *col,
                uint32_t map_size, uint32_t object_size)
 {
-       write_u32(row_index + col->index_offset, map_size - object_size - 1);
-       write_u32(row_index + col->index_offset + 4, object_size + 1);
+       write_u32(row_index + col->index_offset, map_size - object_size);
+       write_u32(row_index + col->index_offset + 4, object_size);
 }
 
 /**
@@ -346,8 +363,8 @@ _static_inline_ char *disk_storage_path(const struct osl_table *t,
  * \sa FOR_EACH_COLUMN_OF_TYPE, FOR_EACH_MAPPED_COLUMN, FOR_EACH_RBTREE_COLUMN,
  * FOR_EACH_DISK_STORAGE_COLUMN, FOR_EACH_VOLATILE_COLUMN, osl_storage_type.
  */
-_static_inline_ int next_column_of_type(enum osl_storage_type type, int col_num,
-               const struct osl_table *t,
+_static_inline_ unsigned next_column_of_type(enum osl_storage_type type,
+               unsigned col_num, const struct osl_table *t,
                const struct osl_column_description **cd)
 {
        *cd = NULL;
@@ -439,12 +456,14 @@ _static_inline_ struct osl_row *get_row_pointer(const struct rb_node *node,
 /**
  * Compute a cryptographic hash of an osl object.
  *
+ * \param t Determines the hash function to use.
  * \param obj the Object to compute the hash value from.
  * \param hash Result is returned here.
  */
-_static_inline_ void hash_object(const struct osl_object *obj, HASH_TYPE *hash)
+_static_inline_ void hash_object(const struct osl_table *t,
+               const struct osl_object *obj, HASH_TYPE *hash)
 {
-       hash_function(obj->data, obj->size, hash);
+       hash_function(t->version, obj->data, obj->size, hash);
 }
 
 /**