-file was missing, forgot to add earlier

author: Christian Grothoff <christian@grothoff.org> 2012-01-14 16:04:58 +0000
committer: Christian Grothoff <christian@grothoff.org> 2012-01-14 16:04:58 +0000
commit: 85967c4d4bd03d68a677f6e8023b192b8b4453f5 (patch)
tree: fdfea34d80d25bf40c1a1e117ef86b65dba5c096 /src/fs/fs_dirmetascan.c
parent: 385d99b60ab8eedc6d26b1e66949a43afafdd79e (diff)
download: gnunet-85967c4d4bd03d68a677f6e8023b192b8b4453f5.tar.gz
gnunet-85967c4d4bd03d68a677f6e8023b192b8b4453f5.zip
1 files changed, 1282 insertions, 0 deletions
diff --git a/src/fs/fs_dirmetascan.c b/src/fs/fs_dirmetascan.c
new file mode 100644
index 000000000..372579ccb
--- /dev/null
+++ b/src/fs/fs_dirmetascan.c
@@ -0,0 +1,1282 @@
+/*
+     This file is part of GNUnet
+     (C) 2005-2012 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
+     option) any later version.
+     GNUnet 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
+     General Public License for more details.
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+#include "platform.h"
+#include "gnunet_fs_service.h"
+#include "gnunet_scheduler_lib.h"
+/**
+ * Entry for each unique keyword to track how often
+ * it occured.  Contains the keyword and the counter.
+ */
+struct KeywordCounter
+{
+  /**
+   * Keyword that was found.
+   */
+  const char *value;
+  /**
+   * How many files have this keyword?
+   */
+  unsigned int count;
+  /**
+   * This is a doubly-linked list
+   */
+  struct KeywordCounter *prev;
+  /**
+   * This is a doubly-linked list
+   */
+  struct KeywordCounter *next;
+};
+/**
+ * Aggregate information we keep for meta data in each directory.
+ */
+struct MetaCounter
+{
+  /**
+   * The actual meta data.
+   */
+  const char *data;
+  /**
+   * Number of bytes in 'data'.
+   */
+  size_t data_size;
+  /**
+   * Name of the plugin that provided that piece of metadata
+   */
+  const char *plugin_name;
+  /**
+   * Type of the data
+   */
+  enum EXTRACTOR_MetaType type;
+  /**
+   * Format of the data
+   */
+  enum EXTRACTOR_MetaFormat format;
+  /**
+   * MIME-type of the metadata itself
+   */
+  const char *data_mime_type;
+  /**
+   * How many files have meta entries matching this value?
+   * (type and format do not have to match).
+   */
+  unsigned int count;
+  /**
+   * This is a doubly-linked list
+   */
+  struct MetaCounter *prev;
+  /**
+   * This is a doubly-linked list
+   */
+  struct MetaCounter *next;
+};
+/**
+ * Execution context for 'add_dir'
+ * Owned by the initiator thread.
+ */
+struct AddDirContext
+{
+  /**
+   * Parent directory (used to access keyword and metadata counters,
+   * and the like).
+   * After the scan is finished, it will contain a pointer to the
+   * top-level directory entry in the directory tree built by the
+   * scanner.
+   */
+  struct ShareTreeItem *parent;
+  /**
+   * Expanded filename (as given by the scan initiator).
+   * The scanner thread stores a copy here, and frees it when it finishes.
+   */
+  char *filename_expanded;
+  /**
+   * A synchronization privitive. Whenever its state is altered,
+   * it means that the initiator wants the scanner to wrap up.
+   * It is owned by the initiator thread.
+   */
+#if WINDOWS
+  HANDLE stop;
+#else
+  sem_t *stop;
+#endif
+  /**
+   * 1 if the scanner should stop, 0 otherwise. Set in response
+   * to communication errors or when the initiator wants the scanning
+   * process to stop.
+   */
+  char do_stop;
+  /**
+   * Handle of the pipe end into which the progress messages are written
+   * The pipe is owned by the initiator thread, and there's no way to
+   * close this end without having access to the pipe, so it won't
+   * be closed by the scanner thread.
+   * The initiator MUST keep it alive until the scanner thread is finished.
+   */
+  const struct GNUNET_DISK_FileHandle *progress_write;
+  /**
+   * List of libextractor plugins to use for extracting.
+   * Initialized when the scan starts, removed when it finishes.
+   */
+  struct EXTRACTOR_PluginList *plugins;
+};
+/**
+ * An opaque structure a pointer to which is returned to the
+ * caller to be used to control the scanner.
+ */
+struct GNUNET_FS_DirScanner
+{
+ /**
+  * A synchronization privitive that is used to signal the scanner to stop.
+  * Owned by the initiator thread.
+  */
+#if WINDOWS
+  HANDLE stop;
+#else
+  sem_t *stop;
+#endif
+ /**
+  * A thread object for the scanner thread.
+  * Owned by the initiator thread.
+  */
+#if WINDOWS
+  HANDLE thread;
+#else
+  pthread_t thread;
+#endif
+ /**
+  * A task for reading progress messages from the scanner.
+  */
+  GNUNET_SCHEDULER_TaskIdentifier progress_read_task;
+ /**
+  * The end of the pipe that is used to read progress messages.
+  */
+  const struct GNUNET_DISK_FileHandle *progress_read;
+ /**
+  * The pipe that is used to read progress messages.
+  * Owned (along with both of its ends) by the initiator thread.
+  * Only closed after the scanner thread is finished.
+  */
+  struct GNUNET_DISK_PipeHandle *progress_pipe;
+ /**
+  * The function that will be called every time there's a progress
+  * message.
+  */
+  GNUNET_FS_DirScannerProgressCallback progress_callback;
+ /**
+  * A closure for progress_callback.
+  */
+  void *cls;
+ /**
+  * A pointer to the context of the scanner.
+  * Owned by the initiator thread.
+  * Initiator thread shouldn't touch it until the scanner thread
+  * is finished.
+  */
+  struct AddDirContext *adc;
+};
+/**
+ * A structure that forms a singly-linked list that serves as a stack
+ * for metadata-processing function.
+ */
+struct ProcessMetadataStackItem
+{
+ /**
+  * A pointer to metadata-processing context.
+  * The same in every stack item.
+  */
+  struct ProcessMetadataContext *ctx;
+ /**
+  * This is a singly-linked list. A pointer to its end is kept, and
+  * this pointer is used to walk it backwards.
+  */
+  struct ProcessMetadataStackItem *parent;
+  /**
+   * Map from the hash over the keyword to an 'struct KeywordCounter *'
+   * counter that says how often this keyword was
+   * encountered in the current directory.
+   */
+  struct GNUNET_CONTAINER_MultiHashMap *keywordcounter;
+  /**
+   * Map from the hash over the metadata to an 'struct MetaCounter *'
+   * counter that says how often this metadata was
+   * encountered in the current directory.
+   */
+  struct GNUNET_CONTAINER_MultiHashMap *metacounter;
+  /**
+   * Number of files in the current directory.
+   */
+  unsigned int dir_entry_count;
+  /**
+   * Keywords to exclude from using for KSK since they'll be associated
+   * with the parent as well.  NULL for nothing blocked.
+   */
+  struct GNUNET_FS_Uri *exclude_ksk;
+ /**
+  * A share tree item that is being processed.
+  */
+  struct ShareTreeItem *item;
+ /**
+  * Set to GNUNET_YES to indicate that the directory pointer by 'item'
+  * was processed, and we should move on to the next.
+  * Otherwise the directory will be recursed into.
+  */
+  int end_directory;
+};
+/**
+ * The structure to keep the state of metadata processing
+ */
+struct ProcessMetadataContext
+{
+ /**
+  * The top of the stack.
+  */
+  struct ProcessMetadataStackItem *stack;
+ /**
+  * Callback to invoke when processing is finished
+  */
+  GNUNET_SCHEDULER_Task cb;
+ /**
+  * Closure for 'cb'
+  */
+  void *cls;
+ /**
+  * Toplevel directory item of the tree to process.
+  */
+  struct ShareTreeItem *toplevel;
+};
+/**
+ * Called every now and then by the scanner.
+ * Checks the synchronization privitive.
+ * Returns 1 if the scanner should stop, 0 otherwise.
+ */
+static int
+should_stop (struct AddDirContext *adc)
+{
+#if WINDOWS
+  if (WaitForSingleObject (adc->stop, 0) == WAIT_TIMEOUT)
+    return 0;
+  adc->do_stop = 1;
+  return 1;
+#else
+  int value;
+  sem_getvalue(adc->stop, &value);  
+  if (value > 0)
+  {
+    adc->do_stop = 1;
+    return 1;
+  }
+  return 0;
+#endif
+}
+/**
+ * Write progress message.
+ * Format is:
+ * <reason><filename length><filename><directory flag>
+ * If filename is NULL, filename is not written, and its length
+ * is written as 0, and nothing else is written. It signals the initiator
+ * thread that the scanner is finished, and that it can now join its thread.
+ *
+ * Also checks if the initiator thread wants the scanner to stop,
+ * Returns 1 to stop scanning (if the signal was received, or
+ * if the pipe was broken somehow), 0 otherwise.
+ */
+static int
+write_progress (struct AddDirContext *adc, const char *filename,
+    char is_directory, enum GNUNET_DirScannerProgressUpdateReason reason)
+{
+  size_t filename_len;
+  size_t wr;
+  size_t total_write;
+  if ((adc->do_stop || should_stop (adc)) && reason != GNUNET_DIR_SCANNER_ASKED_TO_STOP
+      && reason != GNUNET_DIR_SCANNER_FINISHED)
+    return 1;
+  total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+      &reason, sizeof (reason));
+  while (wr > 0 && total_write < sizeof (reason))
+  {
+    total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+      &((char *)&reason)[total_write], sizeof (reason) - total_write);
+    if (wr > 0)
+      total_write += wr;
+  }
+  if (sizeof (reason) != wr)
+    return 1;
+  if (filename)
+    filename_len = strlen (filename) + 1;
+  else
+    filename_len = 0;
+  total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+      &filename_len, sizeof (size_t));
+  while (wr > 0 && total_write < sizeof (size_t))
+  {
+    total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+      &((char *)&filename_len)[total_write], sizeof (size_t) - total_write);
+    if (wr > 0)
+      total_write += wr;
+  }
+  if (sizeof (size_t) != wr)
+    return 1;
+  if (filename)
+  {
+    total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+        filename, filename_len);
+    while (wr > 0 && total_write < filename_len)
+    {
+      total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+        &((char *)filename)[total_write], filename_len - total_write);
+      if (wr > 0)
+        total_write += wr;
+    }
+    if (filename_len != wr)
+      return 1;
+    total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+      &is_directory, sizeof (char));
+    while (wr > 0 && total_write < sizeof (char))
+    {
+      total_write = wr = GNUNET_DISK_file_write (adc->progress_write,
+        &((char *)&is_directory)[total_write], sizeof (char) - total_write);
+      if (wr > 0)
+        total_write += wr;
+    }
+    if (sizeof (char) != wr)
+      return 1;
+  }
+  return 0;
+}
+/**
+ * Add the given keyword to the
+ * keyword statistics tracker.
+ *
+ * @param cls closure (user-defined)
+ * @param keyword the keyword to count
+ * @param is_mandatory ignored
+ * @return always GNUNET_OK
+ */
+static int
+add_to_keyword_counter (void *cls, const char *keyword, int is_mandatory)
+{
+  struct GNUNET_CONTAINER_MultiHashMap *mcm = cls;
+  struct KeywordCounter *cnt, *first_cnt;
+  GNUNET_HashCode hc;
+  size_t klen;
+  klen = strlen (keyword) + 1;
+  GNUNET_CRYPTO_hash (keyword, klen - 1, &hc);
+  /* Since the map might contain multiple values per keyword, we only
+   * store one value, and attach all other to it, forming a linked list.
+   * Somewhat easier than retrieving multiple items via callback.
+   */
+  first_cnt = GNUNET_CONTAINER_multihashmap_get (mcm, &hc);
+  for (cnt = first_cnt; cnt && strcmp (cnt->value, keyword) != 0; cnt = cnt->next);
+  if (cnt == NULL)
+  {
+    cnt = GNUNET_malloc (sizeof (struct KeywordCounter) + klen);
+    cnt->value = (const char *) &cnt[1];
+    memcpy (&cnt[1], keyword, klen);
+    if (first_cnt != NULL)
+    {
+      if (first_cnt->prev != NULL)
+      {
+        first_cnt->prev->next = cnt;
+        cnt->prev = first_cnt->prev;
+      }
+      first_cnt->prev = cnt;
+      cnt->next = first_cnt;
+    }
+    else
+      GNUNET_CONTAINER_multihashmap_put (mcm, &hc, cnt,
+          GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+  }
+  cnt->count++;
+  return GNUNET_OK;
+}
+/**
+ * Type of a function that libextractor calls for each
+ * meta data item found.
+ *
+ * @param cls the container multihashmap to update
+ * @param plugin_name name of the plugin that produced this value;
+ *        special values can be used (i.e. '&lt;zlib&gt;' for zlib being
+ *        used in the main libextractor library and yielding
+ *        meta data).
+ * @param type libextractor-type describing the meta data
+ * @param format basic format information about data
+ * @param data_mime_type mime-type of data (not of the original file);
+ *        can be NULL (if mime-type is not known)
+ * @param data actual meta-data found
+ * @param data_len number of bytes in data
+ * @return GNUNET_OK to continue extracting / iterating
+ */
+static int
+add_to_meta_counter (void *cls, const char *plugin_name,
+                enum EXTRACTOR_MetaType type, enum EXTRACTOR_MetaFormat format,
+                const char *data_mime_type, const char *data, size_t data_len)
+{
+  struct GNUNET_CONTAINER_MultiHashMap *map = cls;
+  GNUNET_HashCode key;
+  struct MetaCounter *cnt, *first_cnt;
+  GNUNET_CRYPTO_hash (data, data_len, &key);
+  first_cnt = GNUNET_CONTAINER_multihashmap_get (map, &key);
+  for (cnt = first_cnt; cnt
+      && cnt->data_size != data_len
+      && memcmp (cnt->data, data, cnt->data_size) != 0; cnt = cnt->next);
+  if (cnt == NULL)
+  {
+    cnt = GNUNET_malloc (sizeof (struct MetaCounter));
+    cnt->data = data;
+    cnt->data_size = data_len;
+    cnt->plugin_name = plugin_name;
+    cnt->type = type;
+    cnt->format = format;
+    cnt->data_mime_type = data_mime_type;
+    if (first_cnt != NULL)
+    {
+      if (first_cnt->prev != NULL)
+      {
+        first_cnt->prev->next = cnt;
+        cnt->prev = first_cnt->prev;
+      }
+      first_cnt->prev = cnt;
+      cnt->next = first_cnt;
+    }
+    else
+      GNUNET_CONTAINER_multihashmap_put (map, &key, cnt,
+          GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
+  }
+  cnt->count++;
+  return 0;
+}
+/**
+ * Allocates a struct ShareTreeItem and adds it to its parent.
+ */
+static struct ShareTreeItem *
+make_item (struct ShareTreeItem *parent)
+{
+  struct ShareTreeItem *item;
+  item = GNUNET_malloc (sizeof (struct ShareTreeItem));
+  item->parent = parent;
+  if (parent)
+    GNUNET_CONTAINER_DLL_insert (parent->children_head, parent->children_tail,
+        item);
+  return item;
+}
+/**
+ * Extract metadata from a file and add it to the share tree
+ *
+ * @param adc context to modify
+ * @param filename name of the file to process
+ */
+static void
+extract_file (struct AddDirContext *adc, const char *filename)
+{
+  struct ShareTreeItem *item;
+  const char *short_fn;
+  item = make_item (adc->parent);
+  GNUNET_DISK_file_size (filename, &item->file_size, GNUNET_YES);
+  item->is_directory = GNUNET_NO;
+  item->meta = GNUNET_CONTAINER_meta_data_create ();
+  GNUNET_FS_meta_data_extract_from_file (item->meta, filename,
+      adc->plugins);
+  GNUNET_CONTAINER_meta_data_delete (item->meta, EXTRACTOR_METATYPE_FILENAME,
+      NULL, 0);
+  short_fn = GNUNET_STRINGS_get_short_name (filename);
+  item->filename = GNUNET_strdup (filename);
+  item->short_filename = GNUNET_strdup (short_fn);
+  GNUNET_CONTAINER_meta_data_insert (item->meta, "<libgnunetfs>",
+                                     EXTRACTOR_METATYPE_FILENAME,
+                                     EXTRACTOR_METAFORMAT_UTF8, "text/plain",
+                                     short_fn, strlen (short_fn) + 1);
+}
+/**
+ * Remove the keyword from the ksk URI.
+ *
+ * @param cls the ksk uri
+ * @param keyword the word to remove
+ * @param is_mandatory ignored
+ * @return always GNUNET_OK
+ */
+static int
+remove_keyword (void *cls, const char *keyword, int is_mandatory)
+{
+  struct GNUNET_FS_Uri *ksk = cls;
+  GNUNET_FS_uri_ksk_remove_keyword (ksk, keyword);
+  return GNUNET_OK;
+}
+/**
+ * Remove keywords from current directory's children, if they are
+ * in the exluded keywords list of that directory.
+ *
+ * @param cls the ksk uri
+ * @param keyword the word to remove
+ * @param is_mandatory ignored
+ * @return always GNUNET_OK
+ */
+static int
+remove_keywords (struct ProcessMetadataStackItem *stack, struct ShareTreeItem *dir)
+{
+  struct ShareTreeItem *item;
+  for (item = dir->children_head; item; item = item->next)
+  {
+    if (stack->exclude_ksk != NULL)
+      GNUNET_FS_uri_ksk_get_keywords (stack->exclude_ksk, &remove_keyword, item->ksk_uri);
+  }
+  return GNUNET_OK;
+}
+/**
+ * Context passed to 'migrate_and_drop'.
+ */
+struct KeywordProcessContext
+{
+  /**
+   * All the keywords we migrated to the parent.
+   */
+  struct GNUNET_FS_Uri *ksk;
+  /**
+   * How often does a keyword have to occur to be
+   * migrated to the parent?
+   */
+  unsigned int threshold;
+};
+/**
+ * Context passed to 'migrate_and_drop'.
+ */
+struct MetaProcessContext
+{
+  /**
+   * All the metadata we copy to the parent.
+   */
+  struct GNUNET_CONTAINER_MetaData *meta;
+  /**
+   * How often does a metadata have to occur to be
+   * migrated to the parent?
+   */
+  unsigned int threshold;
+};
+/**
+ * Move "frequent" keywords over to the
+ * target ksk uri, free the counters.
+ *
+ */
+static int
+migrate_and_drop (void *cls, const GNUNET_HashCode * key, void *value)
+{
+  struct KeywordProcessContext *kpc = cls;
+  struct KeywordCounter *counter = value;
+  if (counter->count >= kpc->threshold && counter->count > 1)
+  {
+    GNUNET_FS_uri_ksk_add_keyword (kpc->ksk, counter->value, GNUNET_NO);
+  }
+  GNUNET_free (counter);
+  return GNUNET_YES;
+}
+/**
+ * Copy "frequent" metadata items over to the
+ * target metadata container, free the counters.
+ *
+ */
+static int
+migrate_and_drop_metadata (void *cls, const GNUNET_HashCode * key, void *value)
+{
+  struct MetaProcessContext *mpc = cls;
+  struct MetaCounter *counter = value;
+  if (counter->count >= mpc->threshold && counter->count > 1)
+  {
+    GNUNET_CONTAINER_meta_data_insert (mpc->meta,
+                                   counter->plugin_name,
+                                   counter->type,
+                                   counter->format,
+                                   counter->data_mime_type, counter->data,
+                                   counter->data_size);
+  }
+  GNUNET_free (counter);
+  return GNUNET_YES;
+}
+/**
+ * Go over the collected keywords from all entries in the
+ * directory and push common keywords up one level (by
+ * adding it to the returned struct). Do the same for metadata.
+ * Destroys keywordcounter and metacoutner for current directory.
+ *
+ * @param adc collection of child meta data
+ * @param exclude_ksk pointer to where moveable keywords will be stored
+ * @param copy_meta pointer to where copyable metadata will be stored
+ */
+static void
+process_keywords_and_metadata (struct ProcessMetadataStackItem *stack,
+    struct GNUNET_FS_Uri **exclude_ksk,
+    struct GNUNET_CONTAINER_MetaData **copy_meta)
+{
+  struct KeywordProcessContext kpc;
+  struct MetaProcessContext mpc;
+  struct GNUNET_CONTAINER_MetaData *tmp;
+  /* Surprisingly, it's impossible to create a ksk with 0 keywords directly.
+   * But we can create one from an empty metadata set
+   */
+  tmp = GNUNET_CONTAINER_meta_data_create ();
+  kpc.ksk = GNUNET_FS_uri_ksk_create_from_meta_data (tmp);
+  GNUNET_CONTAINER_meta_data_destroy (tmp);
+  mpc.meta = GNUNET_CONTAINER_meta_data_create ();
+  kpc.threshold = mpc.threshold = (stack->dir_entry_count + 1) / 2; /* 50% */
+  GNUNET_CONTAINER_multihashmap_iterate (stack->keywordcounter,
+      &migrate_and_drop, &kpc);
+  GNUNET_CONTAINER_multihashmap_iterate (stack->metacounter,
+      &migrate_and_drop_metadata, &mpc);
+  GNUNET_CONTAINER_multihashmap_destroy (stack->keywordcounter);
+  GNUNET_CONTAINER_multihashmap_destroy (stack->metacounter);
+  *exclude_ksk = kpc.ksk;
+  *copy_meta = mpc.meta;
+}
+/**
+ * Function called by the directory iterator to
+ * (recursively) add all of the files in the
+ * directory to the tree.
+ * Called by the directory scanner to initiate the
+ * scan.
+ * TODO: find a way to make it non-recursive.
+ *
+ * @param cls the 'struct AddDirContext*' we're in
+ * @param filename file or directory to scan
+ */
+static int
+scan_directory (void *cls, const char *filename)
+{
+  struct AddDirContext *adc = cls, recurse_adc;
+  struct stat sbuf;
+  struct ShareTreeItem *item;
+  const char *short_fn;
+  int do_stop = 0;
+  /* Wrap up fast */
+  if (adc->do_stop)
+    return GNUNET_SYSERR;
+  /* If the file doesn't exist (or is not statable for any other reason,
+   * skip it, and report it.
+   */
+  if (0 != STAT (filename, &sbuf))
+  {
+    do_stop = write_progress (adc, filename, S_ISDIR (sbuf.st_mode),
+      GNUNET_DIR_SCANNER_DOES_NOT_EXIST);
+    return GNUNET_OK;
+  }
+  /* Report the progress */
+  do_stop = write_progress (adc, filename, S_ISDIR (sbuf.st_mode),
+    GNUNET_DIR_SCANNER_NEW_FILE);
+  if (do_stop)
+  {
+    /* We were asked to stop, acknowledge that and return */
+    do_stop = write_progress (adc, filename, S_ISDIR (sbuf.st_mode),
+      GNUNET_DIR_SCANNER_ASKED_TO_STOP);
+    return GNUNET_SYSERR;
+  }
+  if (!S_ISDIR (sbuf.st_mode))
+    extract_file (adc, filename);
+  else
+  {
+    item = make_item (adc->parent);
+    item->meta = GNUNET_CONTAINER_meta_data_create ();
+    item->is_directory = GNUNET_YES;
+    /* copy fields from adc */
+    recurse_adc = *adc;
+    /* replace recurse_adc contents with the ones for this directory */
+    recurse_adc.parent = item;
+    /* recurse into directory */
+    GNUNET_DISK_directory_scan (filename, &scan_directory, &recurse_adc);
+    short_fn = GNUNET_STRINGS_get_short_name (filename);
+    item->filename = GNUNET_strdup (filename);
+    item->short_filename = GNUNET_strdup (short_fn);
+    if (adc->parent == NULL)
+    {
+      /* we're finished with the scan, make sure caller gets the top-level
+       * directory pointer
+       */
+      adc->parent = item;
+    }
+  }
+  return GNUNET_OK;
+}
+/**
+ * Signals the scanner to finish the scan as fast as possible.
+ * Does not block.
+ * Can close the pipe if asked to, but that is only used by the
+ * internal call to this function during cleanup. The client
+ * must understand the consequences of closing the pipe too early.
+ *
+ * @param ds directory scanner structure
+ * @param close_pipe GNUNET_YES to close
+ */
+void
+GNUNET_FS_directory_scan_finish (struct GNUNET_FS_DirScanner *ds,
+    int close_pipe)
+{
+#if WINDOWS
+  SetEvent (ds->stop);
+#else
+  sem_post (&ds->stop);
+#endif
+  if (close_pipe)
+  {
+    if (ds->progress_read_task != GNUNET_SCHEDULER_NO_TASK)
+    {
+      GNUNET_SCHEDULER_cancel (ds->progress_read_task);
+      ds->progress_read_task = GNUNET_SCHEDULER_NO_TASK;
+    }
+    GNUNET_DISK_pipe_close_end (ds->progress_pipe, GNUNET_DISK_PIPE_END_READ);
+    ds->progress_read = NULL;
+  }
+}
+/**
+ * Signals the scanner thread to finish (in case it isn't finishing
+ * already) and joins the scanner thread. Closes the pipes, frees the
+ * scanner contexts (both of them), returns the results of the scan.
+ * Results are valid (and have to be freed) even if the scanner had
+ * an error or was rushed to finish prematurely.
+ * Blocks until the scanner is finished.
+ *
+ * @param ds directory scanner structure
+ * @return the results of the scan (a directory tree)
+ */
+struct ShareTreeItem *
+GNUNET_FS_directory_scan_cleanup (struct GNUNET_FS_DirScanner *ds)
+{
+  struct ShareTreeItem *result;
+  GNUNET_FS_directory_scan_finish (ds, GNUNET_YES);
+#if WINDOWS
+  WaitForSingleObject (ds->thread, INFINITE);
+  CloseHandle (ds->stop);
+  CloseHandle (ds->thread);
+#else
+  pthread_join (ds->thread, NULL);
+  sem_destroy (&ds->stop);
+  pthread_detach (ds->thread);
+#endif
+  GNUNET_DISK_pipe_close (ds->progress_pipe);
+  result = ds->adc->parent;
+  GNUNET_free (ds->adc);
+  GNUNET_free (ds);
+  return result;
+}
+/**
+ * The function from which the scanner thread starts
+ */
+#if WINDOWS
+static DWORD
+#else
+static int
+#endif
+run_directory_scan_thread (struct AddDirContext *adc)
+{
+  scan_directory (adc, adc->filename_expanded);
+  GNUNET_free (adc->filename_expanded);
+  if (adc->plugins != NULL)
+    EXTRACTOR_plugin_remove_all (adc->plugins);
+  /* Tell the initiator that we're finished, it can now join the thread */
+  write_progress (adc, NULL, 0, GNUNET_DIR_SCANNER_FINISHED);
+  return 0;
+}
+/**
+ * Called every time there is data to read from the scanner.
+ * Calls the scanner progress handler.
+ *
+ * @param cls the closure (directory scanner object)
+ * @param tc task context in which the task is running
+ */
+static void
+read_progress_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_FS_DirScanner *ds;
+  int end_it = 0;
+  enum GNUNET_DirScannerProgressUpdateReason reason;
+  ssize_t rd;
+  ssize_t total_read;
+  size_t filename_len;
+  char is_directory;
+  char *filename;
+  ds = cls;
+  ds->progress_read_task = GNUNET_SCHEDULER_NO_TASK;
+  if (!(tc->reason & GNUNET_SCHEDULER_REASON_READ_READY))
+  {
+    ds->progress_callback (ds->cls, ds, NULL, 0, GNUNET_DIR_SCANNER_SHUTDOWN);
+    return;
+  }
+  /* Read one message. If message is malformed or can't be read, end the scanner */
+  total_read = rd = GNUNET_DISK_file_read (ds->progress_read, &reason, sizeof (reason));
+  while (rd > 0 && total_read < sizeof (reason))
+  {
+    rd = GNUNET_DISK_file_read (ds->progress_read,
+        &((char *) &reason)[total_read],
+        sizeof (reason) - total_read);
+    if (rd > 0)
+      total_read += rd;
+  }
+  if (total_read != sizeof (reason)
+      || reason <= GNUNET_DIR_SCANNER_FIRST
+      || reason >= GNUNET_DIR_SCANNER_LAST)
+  {
+    end_it = 1;
+    reason = GNUNET_DIR_SCANNER_PROTOCOL_ERROR;
+  }
+  if (!end_it)
+  {
+    total_read = rd = GNUNET_DISK_file_read (ds->progress_read, &filename_len,
+        sizeof (size_t));
+    while (rd > 0 && total_read < sizeof (size_t))
+    {
+      rd = GNUNET_DISK_file_read (ds->progress_read,
+          &((char *) &filename_len)[total_read],
+          sizeof (size_t) - total_read);
+      if (rd > 0)
+        total_read += rd;
+    }
+    if (rd != sizeof (size_t))
+    {
+      end_it = 1;
+      reason = GNUNET_DIR_SCANNER_PROTOCOL_ERROR;
+    }
+  }
+  if (!end_it)
+  {
+    if (filename_len == 0)
+      end_it = 1;
+    else if (filename_len > MAX_PATH)
+    {
+      end_it = 1;
+      reason = GNUNET_DIR_SCANNER_PROTOCOL_ERROR;
+    }
+  }
+  if (!end_it)
+  {
+    filename = GNUNET_malloc (filename_len);
+    total_read = rd = GNUNET_DISK_file_read (ds->progress_read, filename,
+        filename_len);
+    while (rd > 0 && total_read < filename_len)
+    {
+      rd = GNUNET_DISK_file_read (ds->progress_read, &filename[total_read],
+          filename_len - total_read);
+      if (rd > 0)
+        total_read += rd;
+    }
+    if (rd != filename_len)
+    {
+      GNUNET_free (filename);
+      reason = GNUNET_DIR_SCANNER_PROTOCOL_ERROR;
+      end_it = 1;
+    }
+  }
+  if (!end_it && filename_len > 0)
+  {
+    total_read = rd = GNUNET_DISK_file_read (ds->progress_read, &is_directory,
+        sizeof (char));
+    while (rd > 0 && total_read < sizeof (char))
+    {
+      rd = GNUNET_DISK_file_read (ds->progress_read, &(&is_directory)[total_read],
+          sizeof (char) - total_read);
+      if (rd > 0)
+        total_read += rd;
+    }
+    if (rd != sizeof (char))
+    {
+      GNUNET_free (filename);
+      reason = GNUNET_DIR_SCANNER_PROTOCOL_ERROR;
+      end_it = 1;
+    }
+  }
+  if (!end_it)
+  {
+    end_it = ds->progress_callback (ds->cls, ds, (const char *) filename, is_directory, reason);
+    GNUNET_free (filename);
+    if (!end_it)
+    {
+      ds->progress_read_task = GNUNET_SCHEDULER_add_read_file (
+          GNUNET_TIME_UNIT_FOREVER_REL, ds->progress_read, &read_progress_task,
+          cls);
+    }
+  }
+  else
+  {
+    ds->progress_callback (ds->cls, ds, NULL, 0, reason);
+  }
+}
+/**
+ * Start a directory scanner thread.
+ *
+ * @param filename name of the directory to scan
+ * @param GNUNET_YES to not to run libextractor on files (only build a tree)
+ * @param ex if not NULL, must be a list of extra plugins for extractor
+ * @param cb the callback to call when there are scanning progress messages
+ * @param cls closure for 'cb'
+ * @return directory scanner object to be used for controlling the scanner
+ */
+struct GNUNET_FS_DirScanner *
+GNUNET_FS_directory_scan_start (const char *filename,
+    int disable_extractor, const char *ex,
+    GNUNET_FS_DirScannerProgressCallback cb, void *cls)
+{
+  struct stat sbuf;
+  struct AddDirContext *adc;
+  char *filename_expanded;
+  struct GNUNET_FS_DirScanner *ds;
+  struct GNUNET_DISK_PipeHandle *progress_pipe;
+  int ok;
+  if (0 != STAT (filename, &sbuf))
+    return NULL;
+  /* TODO: consider generalizing this for files too! */
+  if (!S_ISDIR (sbuf.st_mode))
+  {
+    GNUNET_break (0);
+    return NULL;
+  }
+  /* scan_directory() is guaranteed to be given expanded filenames,
+   * so expand we will!
+   */
+  filename_expanded = GNUNET_STRINGS_filename_expand (filename);
+  if (filename_expanded == NULL)
+    return NULL;
+  progress_pipe = GNUNET_DISK_pipe (GNUNET_NO, GNUNET_NO, GNUNET_NO);
+  if (progress_pipe == NULL)
+  {
+    GNUNET_free (filename_expanded);
+    return NULL;
+  }
+  adc = GNUNET_malloc (sizeof (struct AddDirContext));
+  ds = GNUNET_malloc (sizeof (struct GNUNET_FS_DirScanner));
+  ds->adc = adc;
+#if WINDOWS
+  ds->stop = CreateEvent (NULL, TRUE, FALSE, NULL);
+  adc->stop = ds->stop;
+  ok = ds->stop != INVALID_HANDLE_VALUE;
+#else
+  ok = !sem_init (&ds->stop, 0, 0);
+  adc = &ds->stop;
+#endif
+  if (!ok)
+  {
+    GNUNET_free (adc);
+    GNUNET_free (ds);
+    GNUNET_free (filename_expanded);
+    GNUNET_DISK_pipe_close (progress_pipe);
+    return NULL;
+  }
+  adc->plugins = NULL;
+  if (!disable_extractor)
+  {
+    adc->plugins = EXTRACTOR_plugin_add_defaults (
+        EXTRACTOR_OPTION_DEFAULT_POLICY);
+    if (ex && strlen (ex) > 0)
+      adc->plugins = EXTRACTOR_plugin_add_config (adc->plugins, ex,
+          EXTRACTOR_OPTION_DEFAULT_POLICY);
+  }
+  adc->filename_expanded = filename_expanded;
+  adc->progress_write = GNUNET_DISK_pipe_handle (progress_pipe,
+      GNUNET_DISK_PIPE_END_WRITE);
+  ds->progress_read = GNUNET_DISK_pipe_handle (progress_pipe,
+      GNUNET_DISK_PIPE_END_READ);
+#if WINDOWS
+  ds->thread = CreateThread (NULL, 0,
+      (LPTHREAD_START_ROUTINE) &run_directory_scan_thread, (LPVOID) adc,
+      0, NULL);
+  ok = ds->thread != NULL;
+#else
+  ok = !pthread_create (&ds->thread, NULL, &run_directory_scan_thread,
+      (void *) adc);
+#endif
+  if (!ok)
+  {
+    GNUNET_free (adc);
+    GNUNET_free (filename_expanded);
+    GNUNET_DISK_pipe_close (progress_pipe);
+    GNUNET_free (ds);
+    return NULL;
+  }
+  ds->progress_callback = cb;
+  ds->cls = cls;
+  ds->adc = adc;
+  ds->progress_pipe = progress_pipe;
+  ds->progress_read_task = GNUNET_SCHEDULER_add_read_file (
+      GNUNET_TIME_UNIT_FOREVER_REL, ds->progress_read, &read_progress_task,
+      ds);
+  return ds;
+}
+/**
+ * Task that post-processes the share item tree.
+ * This processing has to be done in the main thread, because
+ * it requires access to libgcrypt's hashing functions, and
+ * libgcrypt is not thread-safe without some special magic.
+ *
+ * @param cls top of the stack
+ * @param tc task context
+ */
+static void
+trim_share_tree_task (void *cls,
+  const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct ProcessMetadataStackItem *stack = cls;
+  struct ProcessMetadataStackItem *next = stack;
+  /* FIXME: figure out what to do when tc says we're shutting down */
+  /* item == NULL means that we've just finished going over the children of
+   * current directory.
+   */
+  if (stack->item == NULL)
+  {
+    if (stack->parent->item != NULL)
+    {
+      /* end of a directory */
+      struct GNUNET_FS_Uri *ksk;
+      /* use keyword and metadata counters to create lists of keywords to move
+       * and metadata to copy.
+       */
+      process_keywords_and_metadata (stack, &stack->parent->exclude_ksk, &stack->parent->item->meta);
+      /* create keywords from metadata (copies all text-metadata as keywords,
+       * AND parses the directory name we've just added, producing even more
+       * keywords.
+       * then merge these keywords with the ones moved from children.
+       */
+      ksk = GNUNET_FS_uri_ksk_create_from_meta_data (stack->parent->item->meta);
+      stack->parent->item->ksk_uri = GNUNET_FS_uri_ksk_merge (ksk, stack->parent->exclude_ksk);
+      GNUNET_FS_uri_destroy (ksk);
+      /* remove moved keywords from children (complete the move) */
+      remove_keywords (stack->parent, stack->parent->item);
+      GNUNET_FS_uri_destroy (stack->parent->exclude_ksk);
+      /* go up the stack */
+      next = stack->parent;
+      GNUNET_free (stack);
+      next->end_directory = GNUNET_YES;
+    }
+    else
+    {
+      /* we've just finished processing the toplevel directory */
+      struct ProcessMetadataContext *ctx = stack->ctx;
+      next = NULL;
+      GNUNET_SCHEDULER_add_continuation (ctx->cb, ctx->cls,
+          GNUNET_SCHEDULER_REASON_PREREQ_DONE);
+      GNUNET_free (stack->parent);
+      GNUNET_free (stack);
+      GNUNET_free (ctx);
+    }
+  }
+  else if (stack->item->is_directory
+      && !stack->end_directory
+      && stack->item->children_head != NULL)
+  {
+    /* recurse into subdirectory */
+    next = GNUNET_malloc (sizeof (struct ProcessMetadataStackItem));
+    next->ctx = stack->ctx;
+    next->item = stack->item->children_head;
+    next->keywordcounter = GNUNET_CONTAINER_multihashmap_create (1024);
+    next->metacounter = GNUNET_CONTAINER_multihashmap_create (1024);
+    next->dir_entry_count = 0;
+    next->parent = stack;
+  }
+  else
+  {
+    /* process a child entry (a file or a directory) and move to the next one*/
+    if (stack->item->is_directory)
+      stack->end_directory = GNUNET_NO;
+    stack->dir_entry_count++;
+    GNUNET_CONTAINER_meta_data_iterate (stack->item->meta, &add_to_meta_counter, stack->metacounter);
+    if (stack->item->is_directory)
+    {
+      char *user = getenv ("USER");
+      if ((user == NULL) || (0 != strncasecmp (user, stack->item->short_filename, strlen(user))))
+      {
+        /* only use filename if it doesn't match $USER */
+        GNUNET_CONTAINER_meta_data_insert (stack->item->meta, "<libgnunetfs>",
+                                           EXTRACTOR_METATYPE_FILENAME,
+                                           EXTRACTOR_METAFORMAT_UTF8,
+                                           "text/plain", stack->item->short_filename,
+                                           strlen (stack->item->short_filename) + 1);
+        GNUNET_CONTAINER_meta_data_insert (stack->item->meta, "<libgnunetfs>",
+                                           EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME,
+                                           EXTRACTOR_METAFORMAT_UTF8,
+                                           "text/plain", stack->item->short_filename,
+                                           strlen (stack->item->short_filename) + 1);
+      }
+    }
+    stack->item->ksk_uri = GNUNET_FS_uri_ksk_create_from_meta_data (stack->item->meta);
+    GNUNET_FS_uri_ksk_get_keywords (stack->item->ksk_uri, &add_to_keyword_counter, stack->keywordcounter);
+    stack->item = stack->item->next;
+  }
+  /* Call this task again later, if there are more entries to process */
+  if (next)
+    GNUNET_SCHEDULER_add_continuation (&trim_share_tree_task, next,
+        GNUNET_SCHEDULER_REASON_PREREQ_DONE);
+}
+/**
+ * Process a share item tree, moving frequent keywords up and
+ * copying frequent metadata up.
+ *
+ * @param toplevel toplevel directory in the tree, returned by the scanner
+ * @param cb called after processing is done
+ * @param cls closure for 'cb'
+ */
+struct ProcessMetadataContext *
+GNUNET_FS_trim_share_tree (struct ShareTreeItem *toplevel,
+    GNUNET_SCHEDULER_Task cb, void *cls)
+{
+  struct ProcessMetadataContext *ret;
+  if (toplevel == NULL)
+  {
+    struct GNUNET_SCHEDULER_TaskContext tc;
+    tc.reason = GNUNET_SCHEDULER_REASON_PREREQ_DONE;
+    cb (cls, &tc);
+    return NULL;
+  }
+  ret = GNUNET_malloc (sizeof (struct ProcessMetadataContext));
+  ret->toplevel = toplevel;
+  ret->stack = GNUNET_malloc (sizeof (struct ProcessMetadataStackItem));
+  ret->stack->ctx = ret;
+  ret->stack->item = toplevel;
+  ret->stack->keywordcounter = GNUNET_CONTAINER_multihashmap_create (1024);
+  ret->stack->metacounter = GNUNET_CONTAINER_multihashmap_create (1024);
+  ret->stack->dir_entry_count = 0;
+  ret->stack->end_directory = GNUNET_NO;
+  /* dummy stack entry that tells us we're at the top of the stack */
+  ret->stack->parent = GNUNET_malloc (sizeof (struct ProcessMetadataStackItem));
+  ret->stack->parent->ctx = ret;
+  ret->cb = cb;
+  ret->cls = cls;
+  GNUNET_SCHEDULER_add_continuation (&trim_share_tree_task, ret->stack,
+    GNUNET_SCHEDULER_REASON_PREREQ_DONE);
+  return ret;
+}
+\ No newline at end of file
author	Christian Grothoff <christian@grothoff.org>	2012-01-14 16:04:58 +0000
committer	Christian Grothoff <christian@grothoff.org>	2012-01-14 16:04:58 +0000
commit	85967c4d4bd03d68a677f6e8023b192b8b4453f5 (patch)
tree	fdfea34d80d25bf40c1a1e117ef86b65dba5c096 /src/fs/fs_dirmetascan.c
parent	385d99b60ab8eedc6d26b1e66949a43afafdd79e (diff)
download	gnunet-85967c4d4bd03d68a677f6e8023b192b8b4453f5.tar.gz gnunet-85967c4d4bd03d68a677f6e8023b192b8b4453f5.zip