even nicer indentation, thanks to LRN's indent patch
[oweals/gnunet.git] / src / fs / fs_tree.h
index bfbd7019b492699b66e35ce7a1f33e025da17226..b39a47cd31f8361a00303e979f92e406121358ba 100644 (file)
@@ -4,7 +4,7 @@
 
      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
@@ -21,7 +21,7 @@
 /**
  * @file fs/fs_tree.h
  * @brief Merkle-tree-ish-CHK file encoding for GNUnet
- * @see http://gnunet.org/encoding.php3
+ * @see https://gnunet.org/encoding
  * @author Krista Bennett
  * @author Christian Grothoff
  *
 #include "fs.h"
 
 /**
- * Compute the depth of the CHK tree.
+ * Compute the depth of the CHK tree.  
  *
  * @param flen file length for which to compute the depth
- * @return depth of the tree
+ * @return depth of the tree, always > 0.  A depth of 1 means only a DBLOCK.
  */
 unsigned int
 GNUNET_FS_compute_depth (uint64_t flen);
 
 
+/**
+ * Calculate how many bytes of payload a block tree of the given
+ * depth MAY correspond to at most (this function ignores the fact that
+ * some blocks will only be present partially due to the total file
+ * size cutting some blocks off at the end).
+ *
+ * @param depth depth of the block.  depth==0 is a DBLOCK.
+ * @return number of bytes of payload a subtree of this depth may correspond to
+ */
+uint64_t
+GNUNET_FS_tree_compute_tree_size (unsigned int depth);
+
+
+/**
+ * Compute how many bytes of data should be stored in
+ * the specified block.
+ *
+ * @param fsize overall file size, must be > 0.
+ * @param offset offset in the original data corresponding
+ *         to the beginning of the tree induced by the block;
+ *         must be < fsize
+ * @param depth depth of the node in the tree, 0 for DBLOCK
+ * @return number of bytes stored in this node
+ */
+size_t
+GNUNET_FS_tree_calculate_block_size (uint64_t fsize, uint64_t offset,
+                                     unsigned int depth);
+
+
 /**
  * Context for an ECRS-based file encoder that computes
  * the Merkle-ish-CHK tree.
@@ -58,19 +87,21 @@ struct GNUNET_FS_TreeEncoder;
  * or (on error) "GNUNET_FS_tree_encode_finish".
  *
  * @param cls closure
- * @param query the query for the block (key for lookup in the datastore)
+ * @param chk content hash key for the block
  * @param offset offset of the block
+ * @param depth depth of the block, 0 for DBLOCKs
  * @param type type of the block (IBLOCK or DBLOCK)
  * @param block the (encrypted) block
  * @param block_size size of block (in bytes)
  */
-typedef void (*GNUNET_FS_TreeBlockProcessor)(void *cls,
-                                            const GNUNET_HashCode *query,
-                                            uint64_t offset,
-                                            uint32_t type,
-                                            const void *block,
-                                            uint16_t block_size);
-                                            
+typedef void (*GNUNET_FS_TreeBlockProcessor) (void *cls,
+                                              const struct ContentHashKey * chk,
+                                              uint64_t offset,
+                                              unsigned int depth,
+                                              enum GNUNET_BLOCK_Type type,
+                                              const void *block,
+                                              uint16_t block_size);
+
 
 /**
  * Function called with information about our
@@ -80,14 +111,13 @@ typedef void (*GNUNET_FS_TreeBlockProcessor)(void *cls,
  * @param offset where are we in the file
  * @param pt_block plaintext of the currently processed block
  * @param pt_size size of pt_block
- * @param depth depth of the block in the tree
+ * @param depth depth of the block in the tree, 0 for DBLOCKS
  */
-typedef void (*GNUNET_FS_TreeProgressCallback)(void *cls,
-                                              uint64_t offset,
-                                              const void *pt_block,
-                                              size_t pt_size,
-                                              unsigned int depth);
-                                              
+typedef void (*GNUNET_FS_TreeProgressCallback) (void *cls, uint64_t offset,
+                                                const void *pt_block,
+                                                size_t pt_size,
+                                                unsigned int depth);
+
 
 /**
  * Initialize a tree encoder.  This function will call "proc" and
@@ -108,13 +138,11 @@ typedef void (*GNUNET_FS_TreeProgressCallback)(void *cls,
  * @return tree encoder context
  */
 struct GNUNET_FS_TreeEncoder *
-GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h,
-                              uint64_t size,
-                              void *cls,
-                              GNUNET_FS_DataReader reader,
-                              GNUNET_FS_TreeBlockProcessor proc,
-                              GNUNET_FS_TreeProgressCallback progress,
-                              GNUNET_SCHEDULER_Task cont);
+GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h, uint64_t size,
+                               void *cls, GNUNET_FS_DataReader reader,
+                               GNUNET_FS_TreeBlockProcessor proc,
+                               GNUNET_FS_TreeProgressCallback progress,
+                               GNUNET_SCHEDULER_Task cont);
 
 
 /**
@@ -125,7 +153,8 @@ GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h,
  *
  * @param te tree encoder to use
  */
-void GNUNET_FS_tree_encoder_next (struct GNUNET_FS_TreeEncoder * te);
+void
+GNUNET_FS_tree_encoder_next (struct GNUNET_FS_TreeEncoder *te);
 
 
 /**
@@ -139,9 +168,9 @@ void GNUNET_FS_tree_encoder_next (struct GNUNET_FS_TreeEncoder * te);
  *        prior to completion and prior to an internal error,
  *        both "*uri" and "*emsg" will be set to NULL).
  */
-void GNUNET_FS_tree_encoder_finish (struct GNUNET_FS_TreeEncoder * te,
-                                   struct GNUNET_FS_Uri **uri,
-                                   char **emsg);
+void
+GNUNET_FS_tree_encoder_finish (struct GNUNET_FS_TreeEncoder *te,
+                               struct GNUNET_FS_Uri **uri, char **emsg);
 
 
 #if 0
@@ -155,9 +184,9 @@ void GNUNET_FS_tree_encoder_finish (struct GNUNET_FS_TreeEncoder * te,
  * @param data set to the resume data
  * @param size set to the size of the resume data
  */
-void GNUNET_FS_tree_encoder_resume_get_data (const struct GNUNET_FS_TreeEncoder * te,
-                                            void **data,
-                                            size_t *size);
+void
+GNUNET_FS_tree_encoder_resume_get_data (const struct GNUNET_FS_TreeEncoder *te,
+                                        void **data, size_t * size);
 
 
 /**
@@ -168,9 +197,9 @@ void GNUNET_FS_tree_encoder_resume_get_data (const struct GNUNET_FS_TreeEncoder
  * @param data the resume data
  * @param size the size of the resume data
  */
-void GNUNET_FS_tree_encoder_resume (struct GNUNET_FS_TreeEncoder * te,
-                                   const void *data,
-                                   size_t size);
+void
+GNUNET_FS_tree_encoder_resume (struct GNUNET_FS_TreeEncoder *te,
+                               const void *data, size_t size);
 #endif
 
 #endif