svn_fs.h

subversion-1.4.3-1.tar.gz 配置svn的源码

/**
 * @copyright
 * ====================================================================
 * Copyright (c) 2000-2004 CollabNet.  All rights reserved.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution.  The terms
 * are also available at http://subversion.tigris.org/license-1.html.
 * If newer versions of this license are posted there, you may use a
 * newer version instead, at your option.
 *
 * This software consists of voluntary contributions made by many
 * individuals.  For exact contribution history, see the revision
 * history and logs, available at http://subversion.tigris.org/.
 * ====================================================================
 * @endcopyright
 *
 * @file svn_fs.h
 * @brief Interface to the Subversion filesystem.
 */


#ifndef SVN_FS_H
#define SVN_FS_H

#include <apr_pools.h>
#include <apr_hash.h>
#include <apr_tables.h>
#include "svn_types.h"
#include "svn_error.h"
#include "svn_delta.h"
#include "svn_io.h"


#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */


/**
 * Get libsvn_fs version information.
 *
 * @since New in 1.1.
 */
const svn_version_t *svn_fs_version(void);


/* Opening and creating filesystems.  */


/** An object representing a Subversion filesystem.  */
typedef struct svn_fs_t svn_fs_t;


/**
 * @name Filesystem configuration options
 * @{
 */
#define SVN_FS_CONFIG_BDB_TXN_NOSYNC            "bdb-txn-nosync"
#define SVN_FS_CONFIG_BDB_LOG_AUTOREMOVE        "bdb-log-autoremove"

/* See also svn_fs_type(). */
/** @since New in 1.1. */
#define SVN_FS_CONFIG_FS_TYPE                   "fs-type"
/** @since New in 1.1. */
#define SVN_FS_TYPE_BDB                         "bdb"
/** @since New in 1.1. */
#define SVN_FS_TYPE_FSFS                        "fsfs"

/** Create repository format compatible with Subversion versions
 * earlier than 1.4.
 * 
 *  @since New in 1.4. 
 */
#define SVN_FS_CONFIG_PRE_1_4_COMPATIBLE        "pre-1.4-compatible"
/** @} */


/**
 * Callers should invoke this function to initialize global state in
 * the FS library before creating FS objects.  If this function is
 * invoked, no FS objects may be created in another thread at the same
 * time as this invocation, and the provided @a pool must last longer
 * than any FS object created subsequently.
 *
 * If this function is not called, the FS library will make a best
 * effort to bootstrap a mutex for protecting data common to FS
 * objects; however, there is a small window of failure.  Also, a
 * small amount of data will be leaked if the Subversion FS library is
 * dynamically unloaded.
 *
 * If this function is called multiple times before the pool passed to
 * the first call is destroyed or cleared, the later calls will have
 * no effect.
 *
 * @since New in 1.2.
 */
svn_error_t *svn_fs_initialize(apr_pool_t *pool);


/** The type of a warning callback function.  @a baton is the value specified
 * in the call to svn_fs_set_warning_func(); the filesystem passes it through
 * to the callback.  @a err contains the warning message.
 *
 * The callback function should not clear the error that is passed to it;
 * its caller should do that.
 */
typedef void (*svn_fs_warning_callback_t)(void *baton, svn_error_t *err);


/** Provide a callback function, @a warning, that @a fs should use to 
 * report (non-fatal) errors.  To print an error, the filesystem will call
 * @a warning, passing it @a warning_baton and the error.
 *
 * By default, this is set to a function that will crash the process.
 * Dumping to @c stderr or <tt>/dev/tty</tt> is not acceptable default 
 * behavior for server processes, since those may both be equivalent to
 * <tt>/dev/null</tt>.
 */
void svn_fs_set_warning_func(svn_fs_t *fs,
                             svn_fs_warning_callback_t warning,
                             void *warning_baton);



/**
 * Create a new, empty Subversion filesystem, stored in the directory
 * @a path, and return a pointer to it in @a *fs_p.  @a path must not
 * currently exist, but its parent must exist.  If @a fs_config is not
 * @c NULL, the options it contains modify the behavior of the
 * filesystem.  The interpretation of @a fs_config is specific to the
 * filesystem back-end.  The new filesystem may be closed by
 * destroying @a pool.
 *
 * @note The lifetime of @a fs_config must not be shorter than @a
 * pool's. It's a good idea to allocate @a fs_config from @a pool or
 * one of its ancestors.
 *
 * If @a fs_config contains a value for @c SVN_FS_CONFIG_FS_TYPE, that
 * value determines the filesystem type for the new filesystem.
 * Currently defined values are:
 *
 *   SVN_FS_TYPE_BDB   Berkeley-DB implementation
 *   SVN_FS_TYPE_FSFS  Native-filesystem implementation
 *
 * If @a fs_config is @c NULL or does not contain a value for
 * @c SVN_FS_CONFIG_FS_TYPE then the default filesystem type will be used.
 * This will typically be BDB for version 1.1 and FSFS for later versions,
 * though the caller should not rely upon any particular default if they
 * wish to ensure that a filesystem of a specific type is created.
 *
 * @since New in 1.1.
 */
svn_error_t *svn_fs_create(svn_fs_t **fs_p, const char *path,
                           apr_hash_t *fs_config, apr_pool_t *pool);

/**
 * Open a Subversion filesystem located in the directory @a path, and
 * return a pointer to it in @a *fs_p.  If @a fs_config is not @c
 * NULL, the options it contains modify the behavior of the
 * filesystem.  The interpretation of @a fs_config is specific to the
 * filesystem back-end.  The opened filesystem may be closed by
 * destroying @a pool.
 *
 * @note The lifetime of @a fs_config must not be shorter than @a
 * pool's. It's a good idea to allocate @a fs_config from @a pool or
 * one of its ancestors.
 *
 * Only one thread may operate on any given filesystem object at once.
 * Two threads may access the same filesystem simultaneously only if
 * they open separate filesystem objects.
 *
 * @note You probably don't want to use this directly.  Take a look at
 * svn_repos_open() instead.
 * 
 * @since New in 1.1.
 */
svn_error_t *svn_fs_open(svn_fs_t **fs_p, const char *path,
                         apr_hash_t *config, apr_pool_t *pool);

/**
 * Return, in @a *fs_type, a string identifying the back-end type of
 * the Subversion filesystem located in @a path.  Allocate @a *fs_type
 * in @a pool.
 *
 * The string should be equal to one of the @c SVN_FS_TYPE_* defined
 * constants, unless the filesystem is a new back-end type added in
 * a later version of Subversion.
 *
 * In general, the type should make no difference in the filesystem's
 * semantics, but there are a few situations (such as backups) where
 * it might matter.
 *
 * @since New in 1.3.
 */
svn_error_t *svn_fs_type(const char **fs_type, const char *path,
                         apr_pool_t *pool);

/**
 * Return the path to @a fs's repository, allocated in @a pool.
 * @note This is just what was passed to svn_fs_create() or
 * svn_fs_open() -- might be absolute, might not.
 * 
 * @since New in 1.1.
 */
const char *svn_fs_path(svn_fs_t *fs, apr_pool_t *pool);

/**
 * Delete the filesystem at @a path.
 *
 * @since New in 1.1.
 */
svn_error_t *svn_fs_delete_fs(const char *path, apr_pool_t *pool);

/**
 * Copy a possibly live Subversion filesystem from @a src_path to
 * @a dest_path.  If @a clean is @c TRUE, perform cleanup on the
 * source filesystem as part of the copy operation; currently, this
 * means deleting copied, unused logfiles for a Berkeley DB source
 * filesystem.
 * 
 * @since New in 1.1.
 */
svn_error_t *svn_fs_hotcopy(const char *src_path, const char *dest_path,
                            svn_boolean_t clean, apr_pool_t *pool);

/** Subversion filesystems based on Berkeley DB.
 *
 * The following functions are specific to Berkeley DB filesystems.
 *
 * @defgroup svn_fs_bdb berkeley db filesystems
 * @{
 */

/** Register an error handling function for Berkeley DB error messages.
 *
 * @deprecated Provided for backward compatibility with the 1.2 API.
 *
 * Despite being first declared deprecated in Subversion 1.3, this API
 * is redundant in versions 1.1 and 1.2 as well.
 *
 * Berkeley DB's error codes are seldom sufficiently informative to allow
 * adequate troubleshooting.  Berkeley DB provides extra messages through
 * a callback function - if an error occurs, the @a handler will be called
 * with two strings: an error message prefix, which will be zero, and
 * an error message.  @a handler might print it out, log it somewhere,
 * etc.
 *
 * Subversion 1.1 and later install their own handler internally, and
 * wrap the messages from Berkeley DB into the standard svn_error_t object,
 * making any information gained through this interface redundant.
 *
 * It is only worth using this function if your program will be used
 * with Subversion 1.0.
 *
 * This function connects to the Berkeley DB @c DBENV->set_errcall interface.
 * Since that interface supports only a single callback, Subversion's internal
 * callback is registered with Berkeley DB, and will forward notifications to
 * a user provided callback after performing its own processing.
 */
svn_error_t *svn_fs_set_berkeley_errcall(svn_fs_t *fs, 
                                         void (*handler)(const char *errpfx,
                                                         char *msg));

/** Perform any necessary non-catastrophic recovery on a Berkeley
 * DB-based Subversion filesystem, stored in the environment @a path.
 * Do any necessary allocation within @a pool.
 *
 * After an unexpected server exit, due to a server crash or a system
 * crash, a Subversion filesystem based on Berkeley DB needs to run
 * recovery procedures to bring the database back into a consistent
 * state and release any locks that were held by the deceased process.
 * The recovery procedures require exclusive access to the database
 * --- while they execute, no other process or thread may access the
 * database.
 *
 * In a server with multiple worker processes, like Apache, if a
 * worker process accessing the filesystem dies, you must stop the
 * other worker processes, and run recovery.  Then, the other worker
 * processes can re-open the database and resume work.
 *
 * If the server exited cleanly, there is no need to run recovery, but
 * there is no harm in it, either, and it take very little time.  So
 * it's a fine idea to run recovery when the server process starts,
 * before it begins handling any requests.
 */
svn_error_t *svn_fs_berkeley_recover(const char *path,
                                     apr_pool_t *pool);


/** Set @a *logfiles to an array of <tt>const char *</tt> log file names
 * of Berkeley DB-based Subversion filesystem.
 *
 * If @a only_unused is @c TRUE, set @a *logfiles to an array which
 * contains only the names of Berkeley DB log files no longer in use
 * by the filesystem.  Otherwise, all log files (used and unused) are
 * returned.
 
 * This function wraps the Berkeley DB 'log_archive' function
 * called by the db_archive binary.  Repository administrators may
 * want to run this function periodically and delete the unused log
 * files, as a way of reclaiming disk space.
 */
svn_error_t *svn_fs_berkeley_logfiles(apr_array_header_t **logfiles,
                                      const char *path,
                                      svn_boolean_t only_unused,
                                      apr_pool_t *pool);


/**
 * The following functions are similar to their generic counterparts.
 *
 * In Subversion 1.2 and earlier, they only work on Berkeley DB filesystems.
 * In Subversion 1.3 and later, they perform largely as aliases for their
 * generic counterparts.
 *
 * @defgroup svn_fs_bdb_deprecated berkeley db filesystem compatibility
 * @{
 */

/** @deprecated Provided for backward compatibility with the 1.0 API. */
svn_fs_t *svn_fs_new(apr_hash_t *fs_config, apr_pool_t *pool);

/** @deprecated Provided for backward compatibility with the 1.0 API. */
svn_error_t *svn_fs_create_berkeley(svn_fs_t *fs, const char *path);

/** @deprecated Provided for backward compatibility with the 1.0 API. */
svn_error_t *svn_fs_open_berkeley(svn_fs_t *fs, const char *path);

/** @deprecated Provided for backward compatibility with the 1.0 API. */
const char *svn_fs_berkeley_path(svn_fs_t *fs, apr_pool_t *pool);