+
/*
This file is part of GNUnet.
(C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Christian Grothoff (and other contributing authors)
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 2, or (at your
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
#ifndef FS_H
#define FS_H
+#include "gnunet_constants.h"
+#include "gnunet_datastore_service.h"
+#include "gnunet_dht_service.h"
+#include "gnunet_fs_service.h"
+#include "gnunet_block_lib.h"
+#include "block_fs.h"
+
+/**
+ * Maximum size of the datastore queue for P2P operations.
+ */
+#define MAX_DATASTORE_QUEUE 16
+
+/**
+ * Maximum number of blocks we keep in memory for migration.
+ */
+#define MAX_MIGRATION_QUEUE 32
+
+/**
+ * How many peers do we select as possible
+ * targets per block obtained for migration?
+ */
+#define MIGRATION_LIST_SIZE 4
+
+/**
+ * To how many peers do we forward each migration block ultimately?
+ * This number must be smaller or equal to MIGRATION_LIST_SIZE. Using
+ * a smaller value allows for variation in available bandwidth (for
+ * migration) between the peers.
+ */
+#define MIGRATION_TARGET_COUNT 2
+
+/**
+ * Ratio for moving average delay calculation. The previous
+ * average goes in with a factor of (n-1) into the calculation.
+ * Must be > 0.
+ */
+#define RUNAVG_DELAY_N 16
+
/**
* Size of the individual blocks used for file-sharing.
*/
-#define GNUNET_FS_DBLOCK_SIZE (32*1024)
+#define DBLOCK_SIZE (32*1024)
+
+/**
+ * Maximum legal size for a kblock.
+ */
+#define MAX_KBLOCK_SIZE (60 * 1024)
+
+/**
+ * Maximum legal size for an sblock.
+ */
+#define MAX_SBLOCK_SIZE (60 * 1024)
+
+/**
+ * Maximum legal size for an nblock.
+ */
+#define MAX_NBLOCK_SIZE (60 * 1024)
+
+/**
+ * Pick a multiple of 2 here to achive 8-byte alignment!
+ * We also probably want DBlocks to have (roughly) the
+ * same size as IBlocks. With SHA-512, the optimal
+ * value is 32768 byte / 128 byte = 256
+ * (128 byte = 2 * 512 bits). DO NOT CHANGE!
+ */
+#define CHK_PER_INODE 256
+
+
+/**
+ * Maximum size for a file to be considered for
+ * inlining in a directory.
+ */
+#define MAX_INLINE_SIZE 65536
+
+
+/**
+ * Blocksize to use when hashing files
+ * for indexing (blocksize for IO, not for
+ * the DBlocks). Larger blocksizes can
+ * be more efficient but will be more disruptive
+ * as far as the scheduler is concerned.
+ */
+#define HASHING_BLOCKSIZE (1024 * 1024)
+
+/**
+ * Number of bits we set per entry in the bloomfilter.
+ * Do not change!
+ */
+#define BLOOMFILTER_K GNUNET_DHT_GET_BLOOMFILTER_K
+
+/**
+ * Number of availability trials we perform per search result.
+ */
+#define AVAILABILITY_TRIALS_MAX 8
+
+/**
+ * Length of the P2P success tracker. Note that
+ * having a very long list can also hurt performance.
+ */
+#define P2P_SUCCESS_LIST_SIZE 8
+
+
+/**
+ * Length of the CS-2-P success tracker. Note that
+ * having a very long list can also hurt performance.
+ */
+#define CS2P_SUCCESS_LIST_SIZE 8
+
+/**
+ * How long are we willing to wait for the datastore to be ready to
+ * process a request for a query without priority?
+ */
+#define BASIC_DATASTORE_REQUEST_DELAY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
+
+
+/**
+ * How long are we willing to wait for the core to be ready to
+ * transmit a reply to the target peer (if we can not transmit
+ * until then, we will discard the reply).
+ */
+#define ACCEPTABLE_REPLY_DELAY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 5)
+
+
+/**
+ * Bandwidth value of an (effectively) 0-priority query.
+ */
+#define QUERY_BANDWIDTH_VALUE 1
+
+/**
+ * Bandwidth value of a 0-priority content (must be
+ * fairly high compared to query since content is
+ * typically significantly larger -- and more valueable
+ * since it can take many queries to get one piece of
+ * content).
+ */
+#define CONTENT_BANDWIDTH_VALUE 800
+
+/**
+ * By which amount do we decrement the TTL for simple forwarding /
+ * indirection of the query; in milli-seconds. Set somewhat in
+ * accordance to your network latency (above the time it'll take you
+ * to send a packet and get a reply).
+ */
+#define TTL_DECREMENT 5000
+
+/**
+ * Until which load do we consider the peer idle and do not
+ * charge at all? (should be larger than GNUNET_IDLE_LOAD_THRESHOLD used
+ * by the rest of the code)!
+ */
+#define IDLE_LOAD_THRESHOLD ((100 + GNUNET_CONSTANTS_IDLE_LOAD_THRESHOLD) / 2)
+
+/**
+ * Name of the directory with top-level searches.
+ */
+#define GNUNET_FS_SYNC_PATH_MASTER_SEARCH "search"
+
+/**
+ * Name of the directory with sub-searches (namespace-updates).
+ */
+#define GNUNET_FS_SYNC_PATH_CHILD_SEARCH "search-child"
+
+/**
+ * Name of the directory with master downloads (not associated
+ * with search or part of another download).
+ */
+#define GNUNET_FS_SYNC_PATH_MASTER_DOWNLOAD "download"
+
+/**
+ * Name of the directory with downloads that are part of another
+ * download or a search.
+ */
+#define GNUNET_FS_SYNC_PATH_CHILD_DOWNLOAD "download-child"
+
+/**
+ * Name of the directory with publishing operations.
+ */
+#define GNUNET_FS_SYNC_PATH_MASTER_PUBLISH "publish"
+
+/**
+ * Name of the directory with files that are being published
+ */
+#define GNUNET_FS_SYNC_PATH_FILE_INFO "publish-file"
+
+/**
+ * Name of the directory with unindex operations.
+ */
+#define GNUNET_FS_SYNC_PATH_MASTER_UNINDEX "unindex"
+
/**
* @brief content hash key
*/
struct ContentHashKey
{
+ /**
+ * Hash of the original content, used for encryption.
+ */
GNUNET_HashCode key;
+
+ /**
+ * Hash of the encrypted content, used for querying.
+ */
GNUNET_HashCode query;
};
/**
* Total size of the file in bytes. (network byte order (!))
*/
- unsigned long long file_length;
+ uint64_t file_length;
/**
* Query and key of the top GNUNET_EC_IBlock.
};
+/**
+ * Types of URIs.
+ */
enum uri_types
-{ chk, sks, ksk, loc };
+ {
+ /**
+ * Content-hash-key (simple file).
+ */
+ chk,
+
+ /**
+ * Signed key space (file in namespace).
+ */
+ sks,
+
+ /**
+ * Keyword search key (query with keywords).
+ */
+ ksk,
+
+ /**
+ * Location (chk with identity of hosting peer).
+ */
+ loc
+ };
/**
* A Universal Resource Identifier (URI), opaque.
*/
struct GNUNET_FS_Uri
{
+ /**
+ * Type of the URI.
+ */
enum uri_types type;
+
union
{
struct
* (only in URI-strings).
*/
char **keywords;
+
+ /**
+ * Size of the keywords array.
+ */
unsigned int keywordCount;
} ksk;
+
struct
{
+ /**
+ * Hash of the public key for the namespace.
+ */
GNUNET_HashCode namespace;
+
+ /**
+ * Human-readable identifier chosen for this
+ * entry in the namespace.
+ */
char *identifier;
} sks;
+
+ /**
+ * Information needed to retrieve a file (content-hash-key
+ * plus file size).
+ */
struct FileIdentifier chk;
+
+ /**
+ * Information needed to retrieve a file including signed
+ * location (identity of a peer) of the content.
+ */
struct Location loc;
} data;
* Information for a file or directory that is
* about to be published.
*/
-struct GNUNET_FS_FileInformation
+struct GNUNET_FS_FileInformation
+{
+
+ /**
+ * Files in a directory are kept as a linked list.
+ */
+ struct GNUNET_FS_FileInformation *next;
+
+ /**
+ * If this is a file in a directory, "dir" refers to
+ * the directory; otherwise NULL.
+ */
+ struct GNUNET_FS_FileInformation *dir;
+
+ /**
+ * Handle to the master context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Pointer kept for the client.
+ */
+ void *client_info;
+
+ /**
+ * Metadata to use for the file.
+ */
+ struct GNUNET_CONTAINER_MetaData *meta;
+
+ /**
+ * Keywords to use for KBlocks.
+ */
+ struct GNUNET_FS_Uri *keywords;
+
+ /**
+ * CHK for this file or directory. NULL if
+ * we have not yet computed it.
+ */
+ struct GNUNET_FS_Uri *chk_uri;
+
+ /**
+ * At what time should the content expire?
+ */
+ struct GNUNET_TIME_Absolute expirationTime;
+
+ /**
+ * At what time did we start this upload?
+ */
+ struct GNUNET_TIME_Absolute start_time;
+
+ /**
+ * Under what filename is this struct serialized
+ * (for operational persistence). Should be determined
+ * using 'mktemp'.
+ */
+ char *serialization;
+
+ /**
+ * Encoder being used to publish this file.
+ */
+ struct GNUNET_FS_TreeEncoder *te;
+
+ /**
+ * Error message (non-NULL if this operation failed).
+ */
+ char *emsg;
+
+ /**
+ * Name of the file or directory (must be an absolute path).
+ */
+ char *filename;
+
+ /**
+ * Data describing either the file or the directory.
+ */
+ union
+ {
+
+ /**
+ * Data for a file.
+ */
+ struct {
+
+ /**
+ * Function that can be used to read the data for the file.
+ */
+ GNUNET_FS_DataReader reader;
+
+ /**
+ * Closure for reader.
+ */
+ void *reader_cls;
+
+ /**
+ * If this file is being indexed, this value is set to the hash
+ * over the entire file (when the indexing process is started).
+ * Otherwise this field is not used.
+ */
+ GNUNET_HashCode file_id;
+
+ /**
+ * Size of the file (in bytes).
+ */
+ uint64_t file_size;
+
+ /**
+ * Should the file be indexed or inserted?
+ */
+ int do_index;
+
+ /**
+ * Is "file_id" already valid? Set to GNUNET_YES once the hash
+ * has been calculated.
+ */
+ int have_hash;
+
+ /**
+ * Has the service confirmed our INDEX_START request?
+ * GNUNET_YES if this step has been completed.
+ */
+ int index_start_confirmed;
+
+ } file;
+
+ /**
+ * Data for a directory.
+ */
+ struct {
+
+ /**
+ * Linked list of entries in the directory.
+ */
+ struct GNUNET_FS_FileInformation *entries;
+
+ /**
+ * Size of the directory itself (in bytes); 0 if the
+ * size has not yet been calculated.
+ */
+ size_t dir_size;
+
+ /**
+ * Pointer to the data for the directory (or NULL if not
+ * available).
+ */
+ void *dir_data;
+
+ } dir;
+
+ } data;
+
+ /**
+ * Desired anonymity level.
+ */
+ uint32_t anonymity;
+
+ /**
+ * Desired priority (for keeping the content in the DB).
+ */
+ uint32_t priority;
+
+ /**
+ * Is this struct for a file or directory?
+ */
+ int is_directory;
+
+ /**
+ * Are we done publishing this file?
+ */
+ int is_published;
+
+};
+
+
+/**
+ * The job is now ready to run and should use the given client
+ * handle to communicate with the FS service.
+ *
+ * @param cls closure
+ * @param client handle to use for FS communication
+ */
+typedef void (*GNUNET_FS_QueueStart)(void *cls,
+ struct GNUNET_CLIENT_Connection *client);
+
+
+/**
+ * The job must now stop to run and should destry the client handle as
+ * soon as possible (ideally prior to returning).
+ */
+typedef void (*GNUNET_FS_QueueStop)(void *cls);
+
+
+/**
+ * Entry in the job queue.
+ */
+struct GNUNET_FS_QueueEntry
{
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_FS_QueueEntry *next;
+
+ /**
+ * This is a linked list.
+ */
+ struct GNUNET_FS_QueueEntry *prev;
+
+ /**
+ * Function to call when the job is started.
+ */
+ GNUNET_FS_QueueStart start;
+
+ /**
+ * Function to call when the job needs to stop (or is done / dequeued).
+ */
+ GNUNET_FS_QueueStop stop;
+
+ /**
+ * Closure for start and stop.
+ */
+ void *cls;
+
+ /**
+ * Handle to FS primary context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Client handle, or NULL if job is not running.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+ /**
+ * Time the job was originally queued.
+ */
+ struct GNUNET_TIME_Absolute queue_time;
+
+ /**
+ * Time the job was started last.
+ */
+ struct GNUNET_TIME_Absolute start_time;
+
+ /**
+ * Total amount of time the job has been running (except for the
+ * current run).
+ */
+ struct GNUNET_TIME_Relative run_time;
+
+ /**
+ * How many blocks do the active downloads have?
+ */
+ unsigned int blocks;
+
+ /**
+ * How often have we (re)started this download?
+ */
+ unsigned int start_times;
};
-#endif
+
+
+/**
+ * Information we store for each search result.
+ */
+struct GNUNET_FS_SearchResult
+{
+
+ /**
+ * Search context this result belongs to.
+ */
+ struct GNUNET_FS_SearchContext *sc;
+
+ /**
+ * URI to which this search result refers to.
+ */
+ struct GNUNET_FS_Uri *uri;
+
+ /**
+ * Metadata for the search result.
+ */
+ struct GNUNET_CONTAINER_MetaData *meta;
+
+ /**
+ * Client info for this search result.
+ */
+ void *client_info;
+
+ /**
+ * ID of a job that is currently probing this results' availability
+ * (NULL if we are not currently probing).
+ */
+ struct GNUNET_FS_DownloadContext *probe_ctx;
+
+ /**
+ * ID of an associated download based on this search result (or
+ * NULL for none).
+ */
+ struct GNUNET_FS_DownloadContext *download;
+
+ /**
+ * If this search result triggered an update search, this field
+ * links to the update search.
+ */
+ struct GNUNET_FS_SearchContext *update_search;
+
+ /**
+ * Name under which this search result is stored on disk.
+ */
+ char *serialization;
+
+ /**
+ * Key for the search result
+ */
+ GNUNET_HashCode key;
+
+ /**
+ * ID of the task that will clean up the probe_ctx should it not
+ * complete on time (and that will need to be cancelled if we clean
+ * up the search result before then).
+ */
+ GNUNET_SCHEDULER_TaskIdentifier probe_cancel_task;
+
+ /**
+ * When did the current probe become active?
+ */
+ struct GNUNET_TIME_Absolute probe_active_time;
+
+ /**
+ * How much longer should we run the current probe before giving up?
+ */
+ struct GNUNET_TIME_Relative remaining_probe_time;
+
+ /**
+ * Number of mandatory keywords for which we have NOT yet found the
+ * search result; when this value hits zero, the search result is
+ * given to the callback.
+ */
+ uint32_t mandatory_missing;
+
+ /**
+ * Number of optional keywords under which this result was also
+ * found.
+ */
+ uint32_t optional_support;
+
+ /**
+ * Number of availability tests that have succeeded for this result.
+ */
+ uint32_t availability_success;
+
+ /**
+ * Number of availability trials that we have performed for this
+ * search result.
+ */
+ uint32_t availability_trials;
+
+};
+
+
+/**
+ * Add a job to the queue.
+ *
+ * @param h handle to the overall FS state
+ * @param start function to call to begin the job
+ * @param stop function to call to pause the job, or on dequeue (if the job was running)
+ * @param cls closure for start and stop
+ * @param blocks number of blocks this download has
+ * @return queue handle
+ */
+struct GNUNET_FS_QueueEntry *
+GNUNET_FS_queue_ (struct GNUNET_FS_Handle *h,
+ GNUNET_FS_QueueStart start,
+ GNUNET_FS_QueueStop stop,
+ void *cls,
+ unsigned int blocks);
+
+
+/**
+ * Dequeue a job from the queue.
+ * @param qh handle for the job
+ */
+void
+GNUNET_FS_dequeue_ (struct GNUNET_FS_QueueEntry *qh);
+
+
+/**
+ * Function that provides data by reading from a file.
+ *
+ * @param cls closure (points to the file information)
+ * @param offset offset to read from; it is possible
+ * that the caller might need to go backwards
+ * a bit at times
+ * @param max maximum number of bytes that should be
+ * copied to buf; readers are not allowed
+ * to provide less data unless there is an error;
+ * a value of "0" will be used at the end to allow
+ * the reader to clean up its internal state
+ * @param buf where the reader should write the data
+ * @param emsg location for the reader to store an error message
+ * @return number of bytes written, usually "max", 0 on error
+ */
+size_t
+GNUNET_FS_data_reader_file_(void *cls,
+ uint64_t offset,
+ size_t max,
+ void *buf,
+ char **emsg);
+
+
+/**
+ * Create the closure for the 'GNUNET_FS_data_reader_file_' callback.
+ *
+ * @param filename file to read
+ * @return closure to use
+ */
+void *
+GNUNET_FS_make_file_reader_context_ (const char *filename);
+
+
+
+/**
+ * Function that provides data by copying from a buffer.
+ *
+ * @param cls closure (points to the buffer)
+ * @param offset offset to read from; it is possible
+ * that the caller might need to go backwards
+ * a bit at times
+ * @param max maximum number of bytes that should be
+ * copied to buf; readers are not allowed
+ * to provide less data unless there is an error;
+ * a value of "0" will be used at the end to allow
+ * the reader to clean up its internal state
+ * @param buf where the reader should write the data
+ * @param emsg location for the reader to store an error message
+ * @return number of bytes written, usually "max", 0 on error
+ */
+size_t
+GNUNET_FS_data_reader_copy_(void *cls,
+ uint64_t offset,
+ size_t max,
+ void *buf,
+ char **emsg);
+
+/**
+ * Notification of FS that a search probe has made progress.
+ * This function is used INSTEAD of the client's event handler
+ * for downloads where the GNUNET_FS_DOWNLOAD_IS_PROBE flag is set.
+ *
+ * @param cls closure, always NULL (!), actual closure
+ * is in the client-context of the info struct
+ * @param info details about the event, specifying the event type
+ * and various bits about the event
+ * @return client-context (for the next progress call
+ * for this operation; should be set to NULL for
+ * SUSPEND and STOPPED events). The value returned
+ * will be passed to future callbacks in the respective
+ * field in the GNUNET_FS_ProgressInfo struct.
+ */
+void*
+GNUNET_FS_search_probe_progress_ (void *cls,
+ const struct GNUNET_FS_ProgressInfo *info);
+
+
+/**
+ * Main function that performs the upload.
+ *
+ * @param cls "struct GNUNET_FS_PublishContext" identifies the upload
+ * @param tc task context
+ */
+void
+GNUNET_FS_publish_main_ (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
+/**
+ * Function called once the hash of the file
+ * that is being unindexed has been computed.
+ *
+ * @param cls closure, unindex context
+ * @param file_id computed hash, NULL on error
+ */
+void
+GNUNET_FS_unindex_process_hash_ (void *cls,
+ const GNUNET_HashCode *file_id);
+
+
+/**
+ * Fill in all of the generic fields for a publish event and call the
+ * callback.
+ *
+ * @param pi structure to fill in
+ * @param sc overall publishing context
+ * @param p file information for the file being published
+ * @param offset where in the file are we so far
+ * @return value returned from callback
+ */
+void *
+GNUNET_FS_publish_make_status_ (struct GNUNET_FS_ProgressInfo *pi,
+ struct GNUNET_FS_PublishContext *sc,
+ const struct GNUNET_FS_FileInformation *p,
+ uint64_t offset);
+
+
+/**
+ * Fill in all of the generic fields for a download event and call the
+ * callback.
+ *
+ * @param pi structure to fill in
+ * @param dc overall download context
+ */
+void
+GNUNET_FS_download_make_status_ (struct GNUNET_FS_ProgressInfo *pi,
+ struct GNUNET_FS_DownloadContext *dc);
+
+
+/**
+ * Fill in all of the generic fields for
+ * an unindex event and call the callback.
+ *
+ * @param pi structure to fill in
+ * @param uc overall unindex context
+ * @param offset where we are in the file (for progress)
+ */
+void
+GNUNET_FS_unindex_make_status_ (struct GNUNET_FS_ProgressInfo *pi,
+ struct GNUNET_FS_UnindexContext *uc,
+ uint64_t offset);
+
+/**
+ * Fill in all of the generic fields for a search event and
+ * call the callback.
+ *
+ * @param pi structure to fill in
+ * @param sc overall search context
+ * @return value returned by the callback
+ */
+void *
+GNUNET_FS_search_make_status_ (struct GNUNET_FS_ProgressInfo *pi,
+ struct GNUNET_FS_SearchContext *sc);
+
+
+/**
+ * Connect to the datastore and remove the blocks.
+ *
+ * @param uc context for the unindex operation.
+ */
+void
+GNUNET_FS_unindex_do_remove_ (struct GNUNET_FS_UnindexContext *uc);
+
+/**
+ * Build the request and actually initiate the search using the
+ * GNUnet FS service.
+ *
+ * @param sc search context
+ * @return GNUNET_OK on success, GNUNET_SYSERR on error
+ */
+int
+GNUNET_FS_search_start_searching_ (struct GNUNET_FS_SearchContext *sc);
+
+/**
+ * Start the downloading process (by entering the queue).
+ *
+ * @param dc our download context
+ */
+void
+GNUNET_FS_download_start_downloading_ (struct GNUNET_FS_DownloadContext *dc);
+
+
+/**
+ * Start download probes for the given search result.
+ *
+ * @param sr the search result
+ */
+void
+GNUNET_FS_search_start_probe_ (struct GNUNET_FS_SearchResult *sr);
+
+/**
+ * Remove serialization/deserialization file from disk.
+ *
+ * @param h master context
+ * @param ext component of the path
+ * @param ent entity identifier
+ */
+void
+GNUNET_FS_remove_sync_file_ (struct GNUNET_FS_Handle *h,
+ const char *ext,
+ const char *ent);
+
+
+/**
+ * Remove serialization/deserialization directory from disk.
+ *
+ * @param h master context
+ * @param ext component of the path
+ * @param uni unique name of parent
+ */
+void
+GNUNET_FS_remove_sync_dir_ (struct GNUNET_FS_Handle *h,
+ const char *ext,
+ const char *uni);
+
+
+/**
+ * Synchronize this file-information struct with its mirror
+ * on disk. Note that all internal FS-operations that change
+ * file information data should already call "sync" internally,
+ * so this function is likely not useful for clients.
+ *
+ * @param fi the struct to sync
+ */
+void
+GNUNET_FS_file_information_sync_ (struct GNUNET_FS_FileInformation *f);
+
+/**
+ * Synchronize this publishing struct with its mirror
+ * on disk. Note that all internal FS-operations that change
+ * publishing structs should already call "sync" internally,
+ * so this function is likely not useful for clients.
+ *
+ * @param pc the struct to sync
+ */
+void
+GNUNET_FS_publish_sync_ (struct GNUNET_FS_PublishContext *pc);
+
+/**
+ * Synchronize this unindex struct with its mirror
+ * on disk. Note that all internal FS-operations that change
+ * publishing structs should already call "sync" internally,
+ * so this function is likely not useful for clients.
+ *
+ * @param uc the struct to sync
+ */
+void
+GNUNET_FS_unindex_sync_ (struct GNUNET_FS_UnindexContext *uc);
+
+/**
+ * Synchronize this search struct with its mirror
+ * on disk. Note that all internal FS-operations that change
+ * publishing structs should already call "sync" internally,
+ * so this function is likely not useful for clients.
+ *
+ * @param sc the struct to sync
+ */
+void
+GNUNET_FS_search_sync_ (struct GNUNET_FS_SearchContext *sc);
+
+/**
+ * Synchronize this search result with its mirror
+ * on disk. Note that all internal FS-operations that change
+ * publishing structs should already call "sync" internally,
+ * so this function is likely not useful for clients.
+ *
+ * @param sr the struct to sync
+ */
+void
+GNUNET_FS_search_result_sync_ (struct GNUNET_FS_SearchResult *sr);
+
+/**
+ * Synchronize this download struct with its mirror
+ * on disk. Note that all internal FS-operations that change
+ * publishing structs should already call "sync" internally,
+ * so this function is likely not useful for clients.
+ *
+ * @param dc the struct to sync
+ */
+void
+GNUNET_FS_download_sync_ (struct GNUNET_FS_DownloadContext *dc);
+
+/**
+ * Create SUSPEND event for the given publish operation
+ * and then clean up our state (without stop signal).
+ *
+ * @param cls the 'struct GNUNET_FS_PublishContext' to signal for
+ */
+void
+GNUNET_FS_publish_signal_suspend_ (void *cls);
+
+/**
+ * Create SUSPEND event for the given search operation
+ * and then clean up our state (without stop signal).
+ *
+ * @param cls the 'struct GNUNET_FS_SearchContext' to signal for
+ */
+void
+GNUNET_FS_search_signal_suspend_ (void *cls);
+
+/**
+ * Create SUSPEND event for the given download operation
+ * and then clean up our state (without stop signal).
+ *
+ * @param cls the 'struct GNUNET_FS_DownloadContext' to signal for
+ */
+void
+GNUNET_FS_download_signal_suspend_ (void *cls);
+
+/**
+ * Create SUSPEND event for the given unindex operation
+ * and then clean up our state (without stop signal).
+ *
+ * @param cls the 'struct GNUNET_FS_UnindexContext' to signal for
+ */
+void
+GNUNET_FS_unindex_signal_suspend_ (void *cls);
+
+/**
+ * Function signature of the functions that can be called
+ * to trigger suspend signals and clean-up for top-level
+ * activities.
+ *
+ * @param cls closure
+ */
+typedef void (*SuspendSignalFunction)(void *cls);
+
+/**
+ * We track all of the top-level activities of FS
+ * so that we can signal 'suspend' on shutdown.
+ */
+struct TopLevelActivity
+{
+ /**
+ * This is a doubly-linked list.
+ */
+ struct TopLevelActivity *next;
+
+ /**
+ * This is a doubly-linked list.
+ */
+ struct TopLevelActivity *prev;
+
+ /**
+ * Function to call for suspend-signalling and clean up.
+ */
+ SuspendSignalFunction ssf;
+
+ /**
+ * Closure for 'ssf' (some struct GNUNET_FS_XXXHandle*)
+ */
+ void *ssf_cls;
+};
+
+
+/**
+ * Create a top-level activity entry.
+ *
+ * @param h global fs handle
+ * @param ssf suspend signal function to use
+ * @param ssf_cls closure for ssf
+ * @return fresh top-level activity handle
+ */
+struct TopLevelActivity *
+GNUNET_FS_make_top (struct GNUNET_FS_Handle *h,
+ SuspendSignalFunction ssf,
+ void *ssf_cls);
+
+
+/**
+ * Destroy a top-level activity entry.
+ *
+ * @param h global fs handle
+ * @param top top level activity entry
+ */
+void
+GNUNET_FS_end_top (struct GNUNET_FS_Handle *h,
+ struct TopLevelActivity *top);
+
+
+
+/**
+ * Master context for most FS operations.
+ */
+struct GNUNET_FS_Handle
+{
+ /**
+ * Scheduler.
+ */
+ struct GNUNET_SCHEDULER_Handle *sched;
+
+ /**
+ * Configuration to use.
+ */
+ const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+ /**
+ * Name of our client.
+ */
+ char *client_name;
+
+ /**
+ * Function to call with updates on our progress.
+ */
+ GNUNET_FS_ProgressCallback upcb;
+
+ /**
+ * Closure for upcb.
+ */
+ void *upcb_cls;
+
+ /**
+ * Head of DLL of top-level activities.
+ */
+ struct TopLevelActivity *top_head;
+
+ /**
+ * Tail of DLL of top-level activities.
+ */
+ struct TopLevelActivity *top_tail;
+
+ /**
+ * Head of DLL of running jobs.
+ */
+ struct GNUNET_FS_QueueEntry *running_head;
+
+ /**
+ * Tail of DLL of running jobs.
+ */
+ struct GNUNET_FS_QueueEntry *running_tail;
+
+ /**
+ * Head of DLL of pending jobs.
+ */
+ struct GNUNET_FS_QueueEntry *pending_head;
+
+ /**
+ * Tail of DLL of pending jobs.
+ */
+ struct GNUNET_FS_QueueEntry *pending_tail;
+
+ /**
+ * Task that processes the jobs in the running and pending queues
+ * (and moves jobs around as needed).
+ */
+ GNUNET_SCHEDULER_TaskIdentifier queue_job;
+
+ /**
+ * Average time we take for a single request to be satisfied.
+ * FIXME: not yet calcualted properly...
+ */
+ struct GNUNET_TIME_Relative avg_block_latency;
+
+ /**
+ * How many actual downloads do we have running right now?
+ */
+ unsigned int active_downloads;
+
+ /**
+ * How many blocks do the active downloads have?
+ */
+ unsigned int active_blocks;
+
+ /**
+ * General flags.
+ */
+ enum GNUNET_FS_Flags flags;
+
+ /**
+ * Maximum number of parallel downloads.
+ */
+ unsigned int max_parallel_downloads;
+
+ /**
+ * Maximum number of parallel requests.
+ */
+ unsigned int max_parallel_requests;
+
+};
+
+
+/**
+ * Handle for controlling a publication process.
+ */
+struct GNUNET_FS_PublishContext
+{
+ /**
+ * Handle to the global fs context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Our top-level activity entry (if we are top-level, otherwise NULL).
+ */
+ struct TopLevelActivity *top;
+
+ /**
+ * File-structure that is being shared.
+ */
+ struct GNUNET_FS_FileInformation *fi;
+
+ /**
+ * Namespace that we are publishing in, NULL if we have no namespace.
+ */
+ struct GNUNET_FS_Namespace *namespace;
+
+ /**
+ * ID of the content in the namespace, NULL if we have no namespace.
+ */
+ char *nid;
+
+ /**
+ * ID for future updates, NULL if we have no namespace or no updates.
+ */
+ char *nuid;
+
+ /**
+ * Filename used for serializing information about this operation
+ * (should be determined using 'mktemp').
+ */
+ char *serialization;
+
+ /**
+ * Our own client handle for the FS service; only briefly used when
+ * we start to index a file, otherwise NULL.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Current position in the file-tree for the upload.
+ */
+ struct GNUNET_FS_FileInformation *fi_pos;
+
+ /**
+ * Non-null if we are currently hashing a file.
+ */
+ struct GNUNET_CRYPTO_FileHashContext *fhc;
+
+ /**
+ * Connection to the datastore service.
+ */
+ struct GNUNET_DATASTORE_Handle *dsh;
+
+ /**
+ * Queue entry for reservation/unreservation.
+ */
+ struct GNUNET_DATASTORE_QueueEntry *qre;
+
+ /**
+ * ID of the task performing the upload. NO_TASK if the upload has
+ * completed.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier upload_task;
+
+ /**
+ * Storage space to reserve for the operation.
+ */
+ uint64_t reserve_space;
+
+ /**
+ * Overall number of entries to reserve for the
+ * publish operation.
+ */
+ uint32_t reserve_entries;
+
+ /**
+ * Typically GNUNET_NO. Set to GNUNET_YES if "upload_task" is
+ * GNUNET_SCHEDULER_NO_TASK and we're waiting for a response from
+ * the datastore service (in which case this struct must not be
+ * freed until we have that response). If someone tries to stop the
+ * download for good during this period, "in_network_wait" is set to
+ * GNUNET_SYSERR which will cause the struct to be destroyed right
+ * after we have the reply (or timeout) from the datastore service.
+ */
+ int in_network_wait;
+
+ /**
+ * Options for publishing.
+ */
+ enum GNUNET_FS_PublishOptions options;
+
+ /**
+ * Space reservation ID with datastore service
+ * for this upload.
+ */
+ int rid;
+
+ /**
+ * Set to GNUNET_YES if all processing has completed.
+ */
+ int all_done;
+};
+
+
+/**
+ * Phases of unindex processing (state machine).
+ */
+enum UnindexState
+ {
+ /**
+ * We're currently hashing the file.
+ */
+ UNINDEX_STATE_HASHING = 0,
+
+ /**
+ * We're telling the datastore to delete
+ * the respective entries.
+ */
+ UNINDEX_STATE_DS_REMOVE = 1,
+
+ /**
+ * We're notifying the FS service about
+ * the unindexing.
+ */
+ UNINDEX_STATE_FS_NOTIFY = 2,
+
+ /**
+ * We're done.
+ */
+ UNINDEX_STATE_COMPLETE = 3,
+
+ /**
+ * We've encountered a fatal error.
+ */
+ UNINDEX_STATE_ERROR = 4
+
+ };
+
+
+/**
+ * Handle for controlling an unindexing operation.
+ */
+struct GNUNET_FS_UnindexContext
+{
+
+ /**
+ * Global FS context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Our top-level activity entry.
+ */
+ struct TopLevelActivity *top;
+
+ /**
+ * Name of the file that we are unindexing.
+ */
+ char *filename;
+
+ /**
+ * Short name under which we are serializing the state of this operation.
+ */
+ char *serialization;
+
+ /**
+ * Connection to the FS service, only valid during the
+ * UNINDEX_STATE_FS_NOTIFY phase.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Connection to the datastore service, only valid during the
+ * UNINDEX_STATE_DS_NOTIFY phase.
+ */
+ struct GNUNET_DATASTORE_Handle *dsh;
+
+ /**
+ * Pointer kept for the client.
+ */
+ void *client_info;
+
+ /**
+ * Merkle-ish tree encoder context.
+ */
+ struct GNUNET_FS_TreeEncoder *tc;
+
+ /**
+ * Handle used to read the file.
+ */
+ struct GNUNET_DISK_FileHandle *fh;
+
+ /**
+ * Error message, NULL on success.
+ */
+ char *emsg;
+
+ /**
+ * Context for hashing of the file.
+ */
+ struct GNUNET_CRYPTO_FileHashContext *fhc;
+
+ /**
+ * Overall size of the file.
+ */
+ uint64_t file_size;
+
+ /**
+ * When did we start?
+ */
+ struct GNUNET_TIME_Absolute start_time;
+
+ /**
+ * Hash of the file's contents (once computed).
+ */
+ GNUNET_HashCode file_id;
+
+ /**
+ * Current operatinonal phase.
+ */
+ enum UnindexState state;
+
+};
+
+
+/**
+ * Information we keep for each keyword in
+ * a keyword search.
+ */
+struct SearchRequestEntry
+{
+ /**
+ * Hash of the original keyword, also known as the
+ * key (for decrypting the KBlock).
+ */
+ GNUNET_HashCode key;
+
+ /**
+ * Hash of the public key, also known as the query.
+ */
+ GNUNET_HashCode query;
+
+ /**
+ * Map that contains a "struct GNUNET_FS_SearchResult" for each result that
+ * was found under this keyword. Note that the entries will point
+ * to the same locations as those in the master result map (in
+ * "struct GNUNET_FS_SearchContext"), so they should not be freed.
+ * The key for each entry is the XOR of the key and query in the CHK
+ * URI (as a unique identifier for the search result).
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *results;
+
+ /**
+ * Is this keyword a mandatory keyword
+ * (started with '+')?
+ */
+ int mandatory;
+
+};
+
+
+/**
+ * Handle for controlling a search.
+ */
+struct GNUNET_FS_SearchContext
+{
+ /**
+ * Handle to the global FS context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Our top-level activity entry (if we are top-level, otherwise NULL).
+ */
+ struct TopLevelActivity *top;
+
+ /**
+ * List of keywords that we're looking for.
+ */
+ struct GNUNET_FS_Uri *uri;
+
+ /**
+ * For update-searches, link to the search result that triggered
+ * the update search; otherwise NULL.
+ */
+ struct GNUNET_FS_SearchResult *psearch_result;
+
+ /**
+ * Connection to the FS service.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Pointer we keep for the client.
+ */
+ void *client_info;
+
+ /**
+ * Name of the file on disk we use for persistence.
+ */
+ char *serialization;
+
+ /**
+ * Error message (non-NULL if this operation failed).
+ */
+ char *emsg;
+
+ /**
+ * Map that contains a "struct GNUNET_FS_SearchResult" for each result that
+ * was found in the search. The key for each entry is the XOR of
+ * the key and query in the CHK URI (as a unique identifier for the
+ * search result).
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *master_result_map;
+
+ /**
+ * Per-keyword information for a keyword search. This array will
+ * have exactly as many entries as there were keywords.
+ */
+ struct SearchRequestEntry *requests;
+
+ /**
+ * When did we start?
+ */
+ struct GNUNET_TIME_Absolute start_time;
+
+ /**
+ * ID of a task that is using this struct and that must be cancelled
+ * when the search is being stopped (if not
+ * GNUNET_SCHEDULER_NO_TASK). Used for the task that adds some
+ * artificial delay when trying to reconnect to the FS service.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier task;
+
+ /**
+ * Anonymity level for the search.
+ */
+ uint32_t anonymity;
+
+ /**
+ * Number of mandatory keywords in this query.
+ */
+ uint32_t mandatory_count;
+
+ /**
+ * Options for the search.
+ */
+ enum GNUNET_FS_SearchOptions options;
+};
+
+
+/**
+ * Information about an active download request.
+ */
+struct DownloadRequest
+{
+ /**
+ * While pending, we keep all download requests in a linked list.
+ */
+ struct DownloadRequest *next;
+
+ /**
+ * CHK for the request.
+ */
+ struct ContentHashKey chk;
+
+ /**
+ * Offset of the corresponding block.
+ */
+ uint64_t offset;
+
+ /**
+ * Depth of the corresponding block in the tree.
+ */
+ unsigned int depth;
+
+ /**
+ * Set if this request is currently in the linked list of pending
+ * requests. Needed in case we get a response for a request that we
+ * have not yet send (i.e. due to two blocks with identical
+ * content); in this case, we would need to remove the block from
+ * the pending list (and need a fast way to check if the block is on
+ * it).
+ */
+ int is_pending;
+
+};
+
+
+/**
+ * Context for controlling a download.
+ */
+struct GNUNET_FS_DownloadContext
+{
+
+ /**
+ * Global FS context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Our top-level activity entry (if we are top-level, otherwise NULL).
+ */
+ struct TopLevelActivity *top;
+
+ /**
+ * Connection to the FS service.
+ */
+ struct GNUNET_CLIENT_Connection *client;
+
+ /**
+ * Parent download (used when downloading files
+ * in directories).
+ */
+ struct GNUNET_FS_DownloadContext *parent;
+
+ /**
+ * Associated search (used when downloading files
+ * based on search results), or NULL for none.
+ */
+ struct GNUNET_FS_SearchResult *search;
+
+ /**
+ * Head of list of child downloads.
+ */
+ struct GNUNET_FS_DownloadContext *child_head;
+
+ /**
+ * Tail of list of child downloads.
+ */
+ struct GNUNET_FS_DownloadContext *child_tail;
+
+ /**
+ * Previous download belonging to the same parent.
+ */
+ struct GNUNET_FS_DownloadContext *prev;
+
+ /**
+ * Next download belonging to the same parent.
+ */
+ struct GNUNET_FS_DownloadContext *next;
+
+ /**
+ * Context kept for the client.
+ */
+ void *client_info;
+
+ /**
+ * URI that identifies the file that
+ * we are downloading.
+ */
+ struct GNUNET_FS_Uri *uri;
+
+ /**
+ * Known meta-data for the file (can be NULL).
+ */
+ struct GNUNET_CONTAINER_MetaData *meta;
+
+ /**
+ * Error message, NULL if we're doing OK.
+ */
+ char *emsg;
+
+ /**
+ * Random portion of filename we use for syncing state of this
+ * download.
+ */
+ char *serialization;
+
+ /**
+ * Where are we writing the data (name of the
+ * file, can be NULL!).
+ */
+ char *filename;
+
+ /**
+ * Where are we writing the data temporarily (name of the
+ * file, can be NULL!); used if we do not have a permanent
+ * name and we are a directory and we do a recursive download.
+ */
+ char *temp_filename;
+
+ /**
+ * Map of active requests (those waiting
+ * for a response). The key is the hash
+ * of the encryped block (aka query).
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *active;
+
+ /**
+ * Linked list of pending requests.
+ */
+ struct DownloadRequest *pending;
+
+ /**
+ * Non-NULL if we are currently having a request for
+ * transmission pending with the client handle.
+ */
+ struct GNUNET_CLIENT_TransmitHandle *th;
+
+ /**
+ * Our entry in the job queue.
+ */
+ struct GNUNET_FS_QueueEntry *job_queue;
+
+ /**
+ * Identity of the peer having the content, or all-zeros
+ * if we don't know of such a peer.
+ */
+ struct GNUNET_PeerIdentity target;
+
+ /**
+ * ID of a task that is using this struct
+ * and that must be cancelled when the download
+ * is being stopped (if not GNUNET_SCHEDULER_NO_TASK).
+ * Used for the task that adds some artificial
+ * delay when trying to reconnect to the FS
+ * service.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier task;
+
+ /**
+ * What was the size of the file on disk that we're downloading
+ * before we started? Used to detect if there is a point in
+ * checking an existing block on disk for matching the desired
+ * content. 0 if the file did not exist already.
+ */
+ uint64_t old_file_size;
+
+ /**
+ * What is the first offset that we're interested
+ * in?
+ */
+ uint64_t offset;
+
+ /**
+ * How many bytes starting from offset are desired?
+ * This is NOT the overall length of the file!
+ */
+ uint64_t length;
+
+ /**
+ * How many bytes have we already received within
+ * the specified range (DBlocks only).
+ */
+ uint64_t completed;
+
+ /**
+ * Time download was started.
+ */
+ struct GNUNET_TIME_Absolute start_time;
+
+ /**
+ * Desired level of anonymity.
+ */
+ uint32_t anonymity;
+
+ /**
+ * The depth of the file-tree.
+ */
+ unsigned int treedepth;
+
+ /**
+ * Options for the download.
+ */
+ enum GNUNET_FS_DownloadOptions options;
+
+ /**
+ * Flag set upon transitive completion (includes child downloads).
+ * This flag is only set to GNUNET_YES for directories where all
+ * child-downloads have also completed (and signalled completion).
+ */
+ int has_finished;
+
+ /**
+ * Have we tried (and failed) to find matching full
+ * data from the meta data yet?
+ */
+ int tried_full_data;
+};
+
+
+/**
+ * Information about an (updateable) node in the
+ * namespace.
+ */
+struct NamespaceUpdateNode
+{
+ /**
+ * Identifier for this node.
+ */
+ char *id;
+
+ /**
+ * Identifier of children of this node.
+ */
+ char *update;
+
+ /**
+ * Metadata for this entry.
+ */
+ struct GNUNET_CONTAINER_MetaData *md;
+
+ /**
+ * URI of this entry in the namespace.
+ */
+ struct GNUNET_FS_Uri *uri;
+
+ /**
+ * Namespace update generation ID. Used to ensure
+ * freshness of the scc_id.
+ */
+ unsigned int nug;
+
+ /**
+ * SCC this entry belongs to (if nug is current).
+ */
+ unsigned int scc_id;
+
+};
+
+
+struct GNUNET_FS_Namespace
+{
+
+ /**
+ * Handle to the FS service context.
+ */
+ struct GNUNET_FS_Handle *h;
+
+ /**
+ * Array with information about nodes in the namespace.
+ */
+ struct NamespaceUpdateNode **update_nodes;
+
+ /**
+ * Private key for the namespace.
+ */
+ struct GNUNET_CRYPTO_RsaPrivateKey *key;
+
+ /**
+ * Hash map mapping identifiers of update nodes
+ * to the update nodes (initialized on-demand).
+ */
+ struct GNUNET_CONTAINER_MultiHashMap *update_map;
+
+ /**
+ * Name of the file with the private key.
+ */
+ char *filename;
+
+ /**
+ * Name of the namespace.
+ */
+ char *name;
+
+ /**
+ * Size of the update nodes array.
+ */
+ unsigned int update_node_count;
+
+ /**
+ * Reference counter.
+ */
+ unsigned int rc;
+
+ /**
+ * Generator for unique nug numbers.
+ */
+ unsigned int nug_gen;
+};
+
+
+/**
+ * Message sent from a GNUnet (fs) publishing activity to the
+ * gnunet-fs-service to initiate indexing of a file. The service is
+ * supposed to check if the specified file is available and has the
+ * same cryptographic hash. It should then respond with either a
+ * confirmation or a denial.
+ *
+ * On OSes where this works, it is considered acceptable if the
+ * service only checks that the path, device and inode match (it can
+ * then be assumed that the hash will also match without actually
+ * computing it; this is an optimization that should be safe given
+ * that the client is not our adversary).
+ */
+struct IndexStartMessage
+{
+
+ /**
+ * Message type will be GNUNET_MESSAGE_TYPE_FS_INDEX_START.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * For alignment.
+ */
+ uint32_t reserved GNUNET_PACKED;
+
+ /**
+ * ID of device containing the file, as seen by the client. This
+ * device ID is obtained using a call like "statvfs" (and converting
+ * the "f_fsid" field to a 32-bit big-endian number). Use 0 if the
+ * OS does not support this, in which case the service must do a
+ * full hash recomputation.
+ */
+ uint64_t device GNUNET_PACKED;
+
+ /**
+ * Inode of the file on the given device, as seen by the client
+ * ("st_ino" field from "struct stat"). Use 0 if the OS does not
+ * support this, in which case the service must do a full hash
+ * recomputation.
+ */
+ uint64_t inode GNUNET_PACKED;
+
+ /**
+ * Hash of the file that we would like to index.
+ */
+ GNUNET_HashCode file_id;
+
+ /* this is followed by a 0-terminated
+ filename of a file with the hash
+ "file_id" as seen by the client */
+
+};
+
+
+/**
+ * Message send by FS service in response to a request
+ * asking for a list of all indexed files.
+ */
+struct IndexInfoMessage
+{
+ /**
+ * Message type will be
+ * GNUNET_MESSAGE_TYPE_FS_INDEX_LIST_ENTRY.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Always zero.
+ */
+ uint32_t reserved GNUNET_PACKED;
+
+ /**
+ * Hash of the indexed file.
+ */
+ GNUNET_HashCode file_id;
+
+ /* this is followed by a 0-terminated
+ filename of a file with the hash
+ "file_id" as seen by the client */
+
+};
+
+
+/**
+ * Message sent from a GNUnet (fs) unindexing activity to the
+ * gnunet-service-fs to indicate that a file will be unindexed. The
+ * service is supposed to remove the file from the list of indexed
+ * files and response with a confirmation message (even if the file
+ * was already not on the list).
+ */
+struct UnindexMessage
+{
+
+ /**
+ * Message type will be
+ * GNUNET_MESSAGE_TYPE_FS_UNINDEX.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Always zero.
+ */
+ uint32_t reserved GNUNET_PACKED;
+
+ /**
+ * Hash of the file that we will unindex.
+ */
+ GNUNET_HashCode file_id;
+
+};
+
+
+/**
+ * Message sent from a GNUnet (fs) search activity to the
+ * gnunet-service-fs to start a search.
+ */
+struct SearchMessage
+{
+
+ /**
+ * Message type will be
+ * GNUNET_MESSAGE_TYPE_FS_START_SEARCH.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Bitmask with options. Zero for no options, one for loopback-only.
+ * Other bits are currently not defined.
+ */
+ int32_t options GNUNET_PACKED;
+
+ /**
+ * Type of the content that we're looking for.
+ */
+ uint32_t type GNUNET_PACKED;
+
+ /**
+ * Desired anonymity level, big-endian.
+ */
+ uint32_t anonymity_level GNUNET_PACKED;
+
+ /**
+ * If the request is for a DBLOCK or IBLOCK, this is the identity of
+ * the peer that is known to have a response. Set to all-zeros if
+ * such a target is not known (note that even if OUR anonymity
+ * level is >0 we may happen to know the responder's identity;
+ * nevertheless, we should probably not use it for a DHT-lookup
+ * or similar blunt actions in order to avoid exposing ourselves).
+ * <p>
+ * If the request is for an SBLOCK, this is the identity of the
+ * pseudonym to which the SBLOCK belongs.
+ * <p>
+ * If the request is for a KBLOCK, "target" must be all zeros.
+ */
+ GNUNET_HashCode target;
+
+ /**
+ * Hash of the keyword (aka query) for KBLOCKs; Hash of
+ * the CHK-encoded block for DBLOCKS and IBLOCKS (aka query)
+ * and hash of the identifier XORed with the target for
+ * SBLOCKS (aka query).
+ */
+ GNUNET_HashCode query;
+
+ /* this is followed by the hash codes of already-known
+ results (which should hence be excluded from what
+ the service returns); naturally, this only applies
+ to queries that can have multiple results, such as
+ those for KBLOCKS (KSK) and SBLOCKS (SKS) */
+};
+
+
+/**
+ * Only the (mandatory) query is included.
+ */
+#define GET_MESSAGE_BIT_QUERY_ONLY 0
+
+/**
+ * The peer identity of a peer waiting for the
+ * reply is included (used if the response
+ * should be transmitted to someone other than
+ * the sender of the GET).
+ */
+#define GET_MESSAGE_BIT_RETURN_TO 1
+
+/**
+ * The hash of the public key of the target
+ * namespace is included (for SKS queries).
+ */
+#define GET_MESSAGE_BIT_SKS_NAMESPACE 2
+
+/**
+ * The peer identity of a peer that had claimed to have the content
+ * previously is included (can be used if responder-anonymity is not
+ * desired; note that the precursor presumably lacked a direct
+ * connection to the specified peer; still, the receiver is in no way
+ * required to limit forwarding only to the specified peer, it should
+ * only prefer it somewhat if possible).
+ */
+#define GET_MESSAGE_BIT_TRANSMIT_TO 4
+
+
+/**
+ * Message sent between peers asking for FS-content.
+ */
+struct GetMessage
+{
+
+ /**
+ * Message type will be GNUNET_MESSAGE_TYPE_FS_GET.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Type of the query (block type).
+ */
+ uint32_t type GNUNET_PACKED;
+
+ /**
+ * How important is this request (network byte order)
+ */
+ uint32_t priority GNUNET_PACKED;
+
+ /**
+ * Relative time to live in MILLISECONDS (network byte order)
+ */
+ int32_t ttl GNUNET_PACKED;
+
+ /**
+ * The content hash should be mutated using this value
+ * before checking against the bloomfilter (used to
+ * get many different filters for the same hash codes).
+ * The number should be in big-endian format when used
+ * for mingling.
+ */
+ int32_t filter_mutator GNUNET_PACKED;
+
+ /**
+ * Which of the optional hash codes are present at the end of the
+ * message? See GET_MESSAGE_BIT_xx constants. For each bit that is
+ * set, an additional GNUNET_HashCode with the respective content
+ * (in order of the bits) will be appended to the end of the GET
+ * message.
+ */
+ uint32_t hash_bitmap GNUNET_PACKED;
+
+ /**
+ * Hashcodes of the file(s) we're looking for.
+ * Details depend on the query type.
+ */
+ GNUNET_HashCode query GNUNET_PACKED;
+
+ /* this is followed by hash codes
+ as specified in the "hash_bitmap";
+ after that, an optional bloomfilter
+ (with bits set for replies that should
+ be suppressed) can be present */
+};
+
+
+/**
+ * Response from FS service with a result for a previous FS search.
+ * Note that queries for DBLOCKS and IBLOCKS that have received a
+ * single response are considered done. This message is transmitted
+ * between peers as well as between the service and a client.
+ */
+struct PutMessage
+{
+
+ /**
+ * Message type will be GNUNET_MESSAGE_TYPE_FS_PUT.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Type of the block (in big endian). Should never be zero.
+ */
+ uint32_t type GNUNET_PACKED;
+
+ /**
+ * When does this result expire?
+ */
+ struct GNUNET_TIME_AbsoluteNBO expiration;
+
+ /* this is followed by the actual encrypted content */
+
+};
+
+
+/**
+ * Message send by a peer that wants to be excluded
+ * from migration for a while.
+ */
+struct MigrationStopMessage
+{
+ /**
+ * Message type will be
+ * GNUNET_MESSAGE_TYPE_FS_MIGRATION_STOP.
+ */
+ struct GNUNET_MessageHeader header;
+
+ /**
+ * Always zero.
+ */
+ uint32_t reserved GNUNET_PACKED;
+
+ /**
+ * How long should the block last?
+ */
+ struct GNUNET_TIME_RelativeNBO duration;
+
+};
+
+
+
+#endif
+
+/* end of fs.h */