/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- nautilus-annotation.c: routines for getting and setting xml-based annotations associated with the digest of a file. Copyright (C) 2001 Eazel, Inc. This program 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 of the License, or (at your option) any later version. This program 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 this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. Author: Andy Hertzfeld */ /* * This code implements the MD5 message-digest algorithm. * The algorithm is due to Ron Rivest. This code was * written by Colin Plumb in 1993, no copyright is claimed. * This code is in the public domain; do with it what you wish. * * Equivalent code is available from RSA Data Security, Inc. * This code has been tested against that, and is equivalent, * except that you don't need to include two pages of legalese * with every copy. * * To compute the message digest of a chunk of bytes, declare an * MD5Context structure, pass it to md5_init, call md5_update as * needed on buffers full of bytes, and then call md5_Final, which * will fill a supplied 16-byte array with the digest. */ /* parts of this file are : * Written March 1993 by Branko Lankester * Modified June 1993 by Colin Plumb for altered md5.c. * Modified October 1995 by Erik Troan for RPM */ #include #include "nautilus-annotation.h" #include "nautilus-file-utilities.h" #include "nautilus-file.h" #include "nautilus-file-private.h" #include "nautilus-global-preferences.h" #include "nautilus-metadata.h" #include "nautilus-preferences.h" #include "nautilus-string.h" #include "nautilus-xml-extensions.h" #include #include #include #include #include #include #include #include /* icon selection callback function. */ typedef void (* NautilusCalculateDigestCallback) (NautilusFile *file, char *file_digest); typedef struct NautilusDigestFileHandle NautilusDigestFileHandle; typedef struct { guint32 buf[4]; guint32 bits[2]; guchar in[64]; int doByteReverse; } MD5Context ; struct NautilusDigestFileHandle { GnomeVFSAsyncHandle *handle; NautilusCalculateDigestCallback callback; NautilusFile *file; char *buffer; gboolean opened; MD5Context digest_context; }; #define READ_CHUNK_SIZE 65536 #define SERVER_URI_TEMPLATE "http://dellbert.differnet.com/get_notes.cgi?ids=%s" static int open_count = 0; static int close_count = 0; static GList* annotation_request_queue = NULL; static GHashTable *files_awaiting_annotation = NULL; static void md5_transform (guint32 buf[4], const guint32 in[16]); static int _ie = 0x44332211; static union _endian { int i; char b[4]; } *_endian = (union _endian *)&_ie; #define IS_BIG_ENDIAN() (_endian->b[0] == '\x44') #define IS_LITTLE_ENDIAN() (_endian->b[0] == '\x11') /* * Note: this code is harmless on little-endian machines. */ static void _byte_reverse (guchar *buf, guint32 longs) { guint32 t; do { t = (guint32) ((guint32) buf[3] << 8 | buf[2]) << 16 | ((guint32) buf[1] << 8 | buf[0]); *(guint32 *) buf = t; buf += 4; } while (--longs); } /** * md5_init: Initialise an md5 context object * @ctx: md5 context * * Initialise an md5 buffer. * **/ static void md5_init (MD5Context *ctx) { ctx->buf[0] = 0x67452301; ctx->buf[1] = 0xefcdab89; ctx->buf[2] = 0x98badcfe; ctx->buf[3] = 0x10325476; ctx->bits[0] = 0; ctx->bits[1] = 0; if (IS_BIG_ENDIAN()) ctx->doByteReverse = 1; else ctx->doByteReverse = 0; } /** * md5_update: add a buffer to md5 hash computation * @ctx: conetxt object used for md5 computaion * @buf: buffer to add * @len: buffer length * * Update context to reflect the concatenation of another buffer full * of bytes. Use this to progressively construct an md5 hash. **/ static void md5_update (MD5Context *ctx, const guchar *buf, guint32 len) { guint32 t; /* Update bitcount */ t = ctx->bits[0]; if ((ctx->bits[0] = t + ((guint32) len << 3)) < t) ctx->bits[1]++; /* Carry from low to high */ ctx->bits[1] += len >> 29; t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */ /* Handle any leading odd-sized chunks */ if (t) { guchar *p = (guchar *) ctx->in + t; t = 64 - t; if (len < t) { memcpy (p, buf, len); return; } memcpy (p, buf, t); if (ctx->doByteReverse) _byte_reverse (ctx->in, 16); md5_transform (ctx->buf, (guint32 *) ctx->in); buf += t; len -= t; } /* Process data in 64-byte chunks */ while (len >= 64) { memcpy (ctx->in, buf, 64); if (ctx->doByteReverse) _byte_reverse (ctx->in, 16); md5_transform (ctx->buf, (guint32 *) ctx->in); buf += 64; len -= 64; } /* Handle any remaining bytes of data. */ memcpy (ctx->in, buf, len); } /* * Final wrapup - pad to 64-byte boundary with the bit pattern * 1 0* (64-bit count of bits processed, MSB-first) */ /** * md5_final: copy the final md5 hash to a bufer * @digest: 16 bytes buffer * @ctx: context containing the calculated md5 * * copy the final md5 hash to a bufer **/ static void md5_final (MD5Context *ctx, guchar digest[16]) { guint32 count; guchar *p; /* Compute number of bytes mod 64 */ count = (ctx->bits[0] >> 3) & 0x3F; /* Set the first char of padding to 0x80. This is safe since there is always at least one byte free */ p = ctx->in + count; *p++ = 0x80; /* Bytes of padding needed to make 64 bytes */ count = 64 - 1 - count; /* Pad out to 56 mod 64 */ if (count < 8) { /* Two lots of padding: Pad the first block to 64 bytes */ memset (p, 0, count); if (ctx->doByteReverse) _byte_reverse (ctx->in, 16); md5_transform (ctx->buf, (guint32 *) ctx->in); /* Now fill the next block with 56 bytes */ memset (ctx->in, 0, 56); } else { /* Pad block to 56 bytes */ memset (p, 0, count - 8); } if (ctx->doByteReverse) _byte_reverse (ctx->in, 14); /* Append length in bits and transform */ ((guint32 *) ctx->in)[14] = ctx->bits[0]; ((guint32 *) ctx->in)[15] = ctx->bits[1]; md5_transform (ctx->buf, (guint32 *) ctx->in); if (ctx->doByteReverse) _byte_reverse ((guchar *) ctx->buf, 4); memcpy (digest, ctx->buf, 16); } /* The four core functions - F1 is optimized somewhat */ /* #define F1(x, y, z) (x & y | ~x & z) */ #define F1(x, y, z) (z ^ (x & (y ^ z))) #define F2(x, y, z) F1(z, x, y) #define F3(x, y, z) (x ^ y ^ z) #define F4(x, y, z) (y ^ (x | ~z)) /* This is the central step in the MD5 algorithm. */ #define MD5STEP(f, w, x, y, z, data, s) \ ( w += f(x, y, z) + data, w = w<>(32-s), w += x ) /* * The core of the MD5 algorithm, this alters an existing MD5 hash to * reflect the addition of 16 longwords of new data. md5_Update blocks * the data and converts bytes into longwords for this routine. */ static void md5_transform (guint32 buf[4], const guint32 in[16]) { register guint32 a, b, c, d; a = buf[0]; b = buf[1]; c = buf[2]; d = buf[3]; MD5STEP (F1, a, b, c, d, in[0] + 0xd76aa478, 7); MD5STEP (F1, d, a, b, c, in[1] + 0xe8c7b756, 12); MD5STEP (F1, c, d, a, b, in[2] + 0x242070db, 17); MD5STEP (F1, b, c, d, a, in[3] + 0xc1bdceee, 22); MD5STEP (F1, a, b, c, d, in[4] + 0xf57c0faf, 7); MD5STEP (F1, d, a, b, c, in[5] + 0x4787c62a, 12); MD5STEP (F1, c, d, a, b, in[6] + 0xa8304613, 17); MD5STEP (F1, b, c, d, a, in[7] + 0xfd469501, 22); MD5STEP (F1, a, b, c, d, in[8] + 0x698098d8, 7); MD5STEP (F1, d, a, b, c, in[9] + 0x8b44f7af, 12); MD5STEP (F1, c, d, a, b, in[10] + 0xffff5bb1, 17); MD5STEP (F1, b, c, d, a, in[11] + 0x895cd7be, 22); MD5STEP (F1, a, b, c, d, in[12] + 0x6b901122, 7); MD5STEP (F1, d, a, b, c, in[13] + 0xfd987193, 12); MD5STEP (F1, c, d, a, b, in[14] + 0xa679438e, 17); MD5STEP (F1, b, c, d, a, in[15] + 0x49b40821, 22); MD5STEP (F2, a, b, c, d, in[1] + 0xf61e2562, 5); MD5STEP (F2, d, a, b, c, in[6] + 0xc040b340, 9); MD5STEP (F2, c, d, a, b, in[11] + 0x265e5a51, 14); MD5STEP (F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); MD5STEP (F2, a, b, c, d, in[5] + 0xd62f105d, 5); MD5STEP (F2, d, a, b, c, in[10] + 0x02441453, 9); MD5STEP (F2, c, d, a, b, in[15] + 0xd8a1e681, 14); MD5STEP (F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); MD5STEP (F2, a, b, c, d, in[9] + 0x21e1cde6, 5); MD5STEP (F2, d, a, b, c, in[14] + 0xc33707d6, 9); MD5STEP (F2, c, d, a, b, in[3] + 0xf4d50d87, 14); MD5STEP (F2, b, c, d, a, in[8] + 0x455a14ed, 20); MD5STEP (F2, a, b, c, d, in[13] + 0xa9e3e905, 5); MD5STEP (F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); MD5STEP (F2, c, d, a, b, in[7] + 0x676f02d9, 14); MD5STEP (F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); MD5STEP (F3, a, b, c, d, in[5] + 0xfffa3942, 4); MD5STEP (F3, d, a, b, c, in[8] + 0x8771f681, 11); MD5STEP (F3, c, d, a, b, in[11] + 0x6d9d6122, 16); MD5STEP (F3, b, c, d, a, in[14] + 0xfde5380c, 23); MD5STEP (F3, a, b, c, d, in[1] + 0xa4beea44, 4); MD5STEP (F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); MD5STEP (F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); MD5STEP (F3, b, c, d, a, in[10] + 0xbebfbc70, 23); MD5STEP (F3, a, b, c, d, in[13] + 0x289b7ec6, 4); MD5STEP (F3, d, a, b, c, in[0] + 0xeaa127fa, 11); MD5STEP (F3, c, d, a, b, in[3] + 0xd4ef3085, 16); MD5STEP (F3, b, c, d, a, in[6] + 0x04881d05, 23); MD5STEP (F3, a, b, c, d, in[9] + 0xd9d4d039, 4); MD5STEP (F3, d, a, b, c, in[12] + 0xe6db99e5, 11); MD5STEP (F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); MD5STEP (F3, b, c, d, a, in[2] + 0xc4ac5665, 23); MD5STEP (F4, a, b, c, d, in[0] + 0xf4292244, 6); MD5STEP (F4, d, a, b, c, in[7] + 0x432aff97, 10); MD5STEP (F4, c, d, a, b, in[14] + 0xab9423a7, 15); MD5STEP (F4, b, c, d, a, in[5] + 0xfc93a039, 21); MD5STEP (F4, a, b, c, d, in[12] + 0x655b59c3, 6); MD5STEP (F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); MD5STEP (F4, c, d, a, b, in[10] + 0xffeff47d, 15); MD5STEP (F4, b, c, d, a, in[1] + 0x85845dd1, 21); MD5STEP (F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); MD5STEP (F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); MD5STEP (F4, c, d, a, b, in[6] + 0xa3014314, 15); MD5STEP (F4, b, c, d, a, in[13] + 0x4e0811a1, 21); MD5STEP (F4, a, b, c, d, in[4] + 0xf7537e82, 6); MD5STEP (F4, d, a, b, c, in[11] + 0xbd3af235, 10); MD5STEP (F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); MD5STEP (F4, b, c, d, a, in[9] + 0xeb86d391, 21); buf[0] += a; buf[1] += b; buf[2] += c; buf[3] += d; } /* When close is complete, there's no more work to do. */ static void digest_file_close_callback (GnomeVFSAsyncHandle *handle, GnomeVFSResult result, gpointer callback_data) { close_count += 1; g_message ("opened %d, closed %d", open_count, close_count); } /* Close the file and then tell the caller we succeeded, handing off * the buffer to the caller. */ static void digest_file_completed (NautilusDigestFileHandle *digest_handle) { guchar digest_result[16]; char digest_string [33]; char* hex_string = "0123456789abcdef"; int index, result_index; int current_value; if (digest_handle->opened) { gnome_vfs_async_close (digest_handle->handle, digest_file_close_callback, NULL); } /* Invoke the callback to continue processing the annotation */ md5_final (&digest_handle->digest_context, digest_result); /* make a hex string for the digest result */ digest_string[32] = '\0'; for (index = 0; index < 32; index++) { current_value = digest_result[index >> 1]; if (index & 1) { result_index = current_value & 15; } else { result_index = (current_value >> 4) & 15; } digest_string[index] = hex_string[result_index]; } (* digest_handle->callback) (digest_handle->file, &digest_string[0]); { char* name = nautilus_file_get_name (digest_handle->file); g_free (name); } nautilus_file_unref (digest_handle->file); g_free (digest_handle->buffer); g_free (digest_handle); } /* Tell the caller we failed. */ static void digest_file_failed (NautilusDigestFileHandle *digest_handle, GnomeVFSResult result) { if (digest_handle->opened) { gnome_vfs_async_close (digest_handle->handle, digest_file_close_callback, NULL); } g_free (digest_handle->buffer); (* digest_handle->callback) (digest_handle->file, NULL); nautilus_file_unref (digest_handle->file); g_free (digest_handle); } /* Here is the callback from the file read routine, where we actually accumulate the checksum */ static void calculate_checksum_callback (GnomeVFSAsyncHandle *handle, GnomeVFSResult result, gpointer buffer, GnomeVFSFileSize bytes_requested, GnomeVFSFileSize bytes_read, gpointer callback_data) { NautilusDigestFileHandle *digest_handle; /* Do a few reality checks. */ g_assert (bytes_requested == READ_CHUNK_SIZE); digest_handle = callback_data; g_assert (digest_handle->handle == handle); g_assert (bytes_read <= bytes_requested); /* Check for a failure. */ if (result != GNOME_VFS_OK && result != GNOME_VFS_ERROR_EOF) { digest_file_failed (digest_handle, result); return; } /* accumulate the recently read data into the checksum */ md5_update (&digest_handle->digest_context, buffer, bytes_read); /* Read more unless we are at the end of the file. */ if (bytes_read > 0 && result == GNOME_VFS_OK) { gnome_vfs_async_read (digest_handle->handle, digest_handle->buffer, READ_CHUNK_SIZE, calculate_checksum_callback, digest_handle); } else { digest_file_completed (digest_handle); } } /* Once the open is finished, read a first chunk. */ static void read_file_open_callback (GnomeVFSAsyncHandle *handle, GnomeVFSResult result, gpointer callback_data) { NautilusDigestFileHandle *digest_handle; char *name; digest_handle = callback_data; g_assert (digest_handle->handle == handle); /* Handle the failure case. */ if (result != GNOME_VFS_OK) { name = nautilus_file_get_name (digest_handle->file); g_message ("open failed, filename %s, error was %d", name, result); g_free (name); digest_file_failed (digest_handle, result); return; } /* read in the first chunk of the file */ digest_handle->opened = TRUE; open_count += 1; gnome_vfs_async_read (digest_handle->handle, digest_handle->buffer, READ_CHUNK_SIZE, calculate_checksum_callback, digest_handle); } /* calculate the digest for the passed-in file asynchronously, invoking the passed in * callback when the calculation has been completed. */ static NautilusDigestFileHandle* calculate_file_digest (NautilusFile *file, NautilusCalculateDigestCallback callback) { NautilusDigestFileHandle *handle; char *uri; /* if annotation lookup is disabled, don't bother to do all this work */ if (!nautilus_preferences_get_boolean (NAUTILUS_PREFERENCES_LOOKUP_ANNOTATIONS)) { return 0; } /* allocate a digest-handle structure to keep our state */ handle = g_new0 (NautilusDigestFileHandle, 1); uri = nautilus_file_get_uri (file); handle->callback = callback; handle->opened = FALSE; handle->file = file; nautilus_file_ref (file); /* allocate the buffer */ handle->buffer = g_malloc (READ_CHUNK_SIZE); /* initialize the MD5 stuff */ md5_init (&handle->digest_context); /* open the file */ gnome_vfs_async_open (&handle->handle, uri, GNOME_VFS_OPEN_READ, read_file_open_callback, handle); g_free (uri); return handle; } /* given a digest, retrieve an associated file object from the hash table */ static NautilusFile * get_file_from_digest (const char *digest) { if (files_awaiting_annotation == NULL) { return NULL; } return g_hash_table_lookup (files_awaiting_annotation, digest); } /* given a digest value, return the path to it in the local cache */ static char * get_annotation_path (const char *digest) { char *user_directory, *annotation_directory; char *annotation_path, *directory_uri; user_directory = nautilus_get_user_directory (); annotation_directory = nautilus_make_path (user_directory, "annotations"); annotation_path = nautilus_make_path (annotation_directory, digest); /* create the annotation directory if it doesn't exist */ if (!g_file_exists (annotation_directory)) { directory_uri = gnome_vfs_get_uri_from_local_path (annotation_directory); gnome_vfs_make_directory (directory_uri, GNOME_VFS_PERM_USER_ALL | GNOME_VFS_PERM_GROUP_ALL | GNOME_VFS_PERM_OTHER_READ); g_free (directory_uri); } /* free up the intermediate strings and return the complete path */ g_free (user_directory); g_free (annotation_directory); return annotation_path; } /* look up the passed-in digest in the local annotation cache */ static char * look_up_local_annotation (NautilusFile *file, const char *digest) { GnomeVFSResult result; int file_size; char *uri, *path, *file_data, *buffer; path = get_annotation_path (digest); if (g_file_exists (path)) { /* load the file and return it */ uri = gnome_vfs_get_uri_from_local_path (path); result = nautilus_read_entire_file (uri, &file_size, &file_data); g_free (uri); g_free (path); if (result == GNOME_VFS_OK) { /* add a null at the end, so it's a valid string */ buffer = g_realloc (file_data, file_size + 1); buffer[file_size] = '\0'; return buffer; } else { return NULL; } } g_free (path); return NULL; } static gboolean has_local_annotation (const char *digest) { gboolean has_annotation; char *path; path = get_annotation_path (digest); has_annotation = g_file_exists (path); g_free (path); return has_annotation; } /* utility routine to add the passed-in xml node to the file associated with the passed-in * digest. If there isn't a file, create one */ static void add_annotations_to_file (xmlNodePtr node_ptr, const char *digest) { char *digest_path; xmlDocPtr document; digest_path = get_annotation_path (digest); /* save the subtree as a new document, by making a new document and adding the new node */ document = xmlNewDoc ("1.0"); xmlDocSetRootElement (document, node_ptr); /* save the xml tree as a file in the cache area */ xmlSaveFile (digest_path, document); xmlFreeDoc (document); g_free (digest_path); } /* remember the file object by adding it to a hash table */ static void remember_file (NautilusFile *file, const char *digest) { nautilus_file_ref (file); if (files_awaiting_annotation == NULL) { files_awaiting_annotation = g_hash_table_new (g_str_hash, g_str_equal); /* g_atexit (annotations_file_table_free); */ } g_hash_table_insert (files_awaiting_annotation, g_strdup (digest), file); } /* forget a file when we're done with it by removing it from the table */ static void forget_file (const char *digest) { NautilusFile *file; if (files_awaiting_annotation == NULL) { return; } file = g_hash_table_lookup (files_awaiting_annotation, digest); if (file != NULL) { nautilus_file_unref (file); g_hash_table_remove (files_awaiting_annotation, digest); } } /* completion routine invoked when we've loaded the an annotation file from the service. * We must parse it, and walk through it to save the annotations in the local cache. */ static void got_annotations_callback (GnomeVFSResult result, GnomeVFSFileSize file_size, char *file_contents, gpointer callback_data) { NautilusFile *file; xmlDocPtr annotations; xmlNodePtr next_annotation, item; xmlNodePtr saved_annotation; int annotation_count; char *buffer, *digest, *info_str; time_t date_stamp; /* exit if there was an error */ if (result != GNOME_VFS_OK) { g_assert (file_contents == NULL); return; } g_message ("got annotation response %s", file_contents); /* inexplicably, the gnome-xml parser requires a zero-terminated array, so add the null at the end. */ buffer = g_realloc (file_contents, file_size + 1); buffer[file_size] = '\0'; annotations = xmlParseMemory (buffer, file_size); g_free (buffer); /* iterate through the xml document, handling each annotation entry */ if (annotations != NULL) { next_annotation = xmlDocGetRootElement (annotations)->childs; while (next_annotation != NULL) { if (nautilus_strcmp (next_annotation->name, "annotations") == 0) { /* get the digest associated with the annotations */ digest = xmlGetProp (next_annotation, "digest"); if (digest != NULL) { /* count the number of annotations contained in the node */ annotation_count = 0; item = next_annotation->childs; while (item != NULL) { if (nautilus_strcmp (item->name, "annotation") == 0) { annotation_count += 1; } item = item->next; } /* write the annotation out to our cache area, if necessary */ if (annotation_count > 0) { saved_annotation = xmlCopyNode (next_annotation, TRUE); add_annotations_to_file (saved_annotation, digest); } /* retrieve the file object, and update it's count and time stamp */ file = get_file_from_digest (digest); time (&date_stamp); info_str = g_strdup_printf ("%lu:%d", date_stamp, annotation_count); nautilus_file_set_metadata (file, NAUTILUS_METADATA_KEY_NOTES_INFO, NULL, info_str); g_free (info_str); /* issue the changed signal */ nautilus_file_emit_changed (file); /* remove the file from the hash table and unref it */ forget_file (digest); xmlFree (digest); } } next_annotation = next_annotation->next; } /* free the xml document */ xmlFreeDoc (annotations); } } /* format the request, and send it to the server */ /* the first cut implementation simply sends the digests as a cgi parameter, * but soon we'll want use SOAP or XML-RPC */ static void fetch_annotations_from_server (void) { GString *temp_string; GList *current_entry, *save_entry; char *uri; /* check to see if there are enough requests, or a long enough delay since the last one */ current_entry = annotation_request_queue; save_entry = current_entry; annotation_request_queue = NULL; /* simple cgi-based request format passed the digests as part of the uri, so * gather the variable parts */ temp_string = g_string_new (""); while (current_entry != NULL) { g_string_append (temp_string, (char*) current_entry->data); if (current_entry->next != NULL) { g_string_append (temp_string, ","); } current_entry = current_entry->next; } uri = g_strdup_printf (SERVER_URI_TEMPLATE, temp_string->str); g_string_free (temp_string, TRUE); nautilus_g_list_free_deep (save_entry); /* read the result from the server asynchronously */ nautilus_read_entire_file_async (uri, got_annotations_callback, NULL); g_free (uri); } /* ask the server for an annotation asynchronously */ static void get_annotation_from_server (NautilusFile *file, const char *file_digest) { /* see if there's a request for this one already pending - if so, we can return */ if (get_file_from_digest (file_digest) != NULL) { return; } /* only do this if lookups are enabled */ /* if annotation lookup is disabled, don't bother to do all this work */ if (!nautilus_preferences_get_boolean (NAUTILUS_PREFERENCES_LOOKUP_ANNOTATIONS)) { return; } /* add the request to the queue, and kick it off it there's enough of them */ annotation_request_queue = g_list_prepend (annotation_request_queue, g_strdup (file_digest)); remember_file (file, file_digest); fetch_annotations_from_server (); } /* callback that's invokes when we've finished calculating the file's digest. Remember * it in the metadata, and look up the associated annotation */ static void got_file_digest (NautilusFile *file, const char *file_digest) { if (file_digest == NULL) { return; } /* save the digest in the file metadata */ nautilus_file_set_metadata (file, NAUTILUS_METADATA_KEY_FILE_DIGEST, NULL, file_digest); /* lookup the annotations associated with the file. If there is one, flag the change and we're done */ if (has_local_annotation (file_digest)) { nautilus_file_emit_changed (file); return; } /* there isn't a local annotation, so ask the server for one */ get_annotation_from_server (file, file_digest); return; } /* return the annotation associated with a file. If we haven't inspected this file yet, * return NULL but queue a request for an annotation lookup, which will be processed * asynchronously and issue a "file_changed" signal if any is found. */ char *nautilus_annotation_get_annotation (NautilusFile *file) { char *digest; char *annotations; char *digest_info; /* if it's a directory, return NULL, at least until we figure out how to handle directory * annotations */ if (nautilus_file_is_directory (file)) { return NULL; } /* see if there's a digest available in metadata */ digest = nautilus_file_get_metadata (file, NAUTILUS_METADATA_KEY_FILE_DIGEST, NULL); /* there isn't a digest, so start a request for one going, and return NULL */ if (digest == NULL) { calculate_file_digest (file, (NautilusCalculateDigestCallback) got_file_digest); return NULL; } /* there's a digest, so we if we have the annotations for the file cached locally */ annotations = look_up_local_annotation (file, digest); if (annotations != NULL) { g_free (digest); return annotations; } /* we don't have a local annotation, so queue a request from the server, if we haven't already tried */ /* soon, we'll inspect the time stamp, and look it up anyway if it's too old */ digest_info = nautilus_file_get_metadata (file, NAUTILUS_METADATA_KEY_NOTES_INFO, NULL); if (digest_info == NULL) { get_annotation_from_server (file, digest); } else { g_free (digest_info); } g_free (digest); return NULL; } /* return the number of annotations associated with the passed in file. If we don't know, * return 0, but queue a request like above */ int nautilus_annotation_has_annotation (NautilusFile *file) { char *digest_info, *digits, *temp_str; int count; if (!nautilus_preferences_get_boolean (NAUTILUS_PREFERENCES_DISPLAY_ANNOTATIONS)) { return 0; } digest_info = nautilus_file_get_metadata (file, NAUTILUS_METADATA_KEY_NOTES_INFO, NULL); if (digest_info != NULL) { digits = strrchr (digest_info, ':'); count = atoi (digits + 1); g_free (digest_info); return count; } else { /* initiate fetching the annotations from the server */ temp_str = nautilus_annotation_get_annotation (file); g_free (temp_str); } g_free (digest_info); return 0; } /* add an annotation to a file */ void nautilus_annotation_add_annotation (NautilusFile *file, const char *new_annotation) { } /* remove an annotation from a file */ void nautilus_annotation_remove_annotation (NautilusFile *file, int which_annotation) { }