...

resources/mime.types

@@ -822,7 +822,6 @@ application/x-lzh				lzh
 application/x-lzx				lzx
 application/x-maker				book fb fbdoc fm frame frm maker
 application/x-mif				mif
-application/x-mobipocket-ebook				mobi prc
 application/x-ms-application				application
 application/x-ms-wmd				wmd
 application/x-ms-wmz				wmz
@@ -1371,11 +1370,11 @@ application/x-sony-bbeb                    lrf lrx
 application/adobe-page-template+xml        xpgt
 application/x-font-opentype                otf
 application/x-font-truetype                ttf
-application/x-mobipocket-ebook             mobi prc azw
+application/x-mobipocket-ebook             mobi prc 
+application/vnd.amazon.ebook               azw3 azw azw2 azw4
 application/x-cbz                          cbz
 application/x-cbr                          cbr
 application/x-cb7                          cb7
 application/x-koboreader-ebook             kobo
 image/wmf                                  wmf
 application/ereader                        pdb
-

src/calibre/__init__.py

@@ -54,6 +54,16 @@ def guess_all_extensions(*args, **kwargs):
         _init_mimetypes()
     return mimetypes.guess_all_extensions(*args, **kwargs)
 
+
+def guess_extension(*args, **kwargs):
+    import mimetypes
+    if not _mt_inited:
+        _init_mimetypes()
+    ext = mimetypes.guess_extension(*args, **kwargs)
+    if not ext and args and args[0] == 'application/x-palmreader':
+        ext = '.pdb'
+    return ext
+
 def get_types_map():
     import mimetypes
     if not _mt_inited:

src/calibre/customize/builtins.py

@@ -1351,6 +1351,15 @@ class StoreEbookscomStore(StoreBase):
     formats = ['EPUB', 'LIT', 'MOBI', 'PDF']
     affiliate = True
 
+# class StoreEbooksGratuitsStore(StoreBase):
+#     name = 'EbooksGratuits.com'
+#     description = u''
+#     actual_plugin = 'calibre.gui2.store.stores.ebooksgratuits_plugin:EbooksGratuitsStore'
+#
+#     headquarters = 'FR'
+#     formats = ['EPUB', 'MOBI', 'PDF', 'PDB']
+#     drm_free_only = True
+#
 # class StoreEBookShoppeUKStore(StoreBase):
 #     name = 'ebookShoppe UK'
 #     author = u'Charles Haley'
@@ -1645,6 +1654,7 @@ plugins += [
     StoreEbookNLStore,
     StoreEbookpointStore,
     StoreEbookscomStore,
+    # StoreEbooksGratuitsStore,
     StoreEHarlequinStore,
     StoreEKnigiStore,
     StoreEscapeMagazineStore,

src/calibre/gui2/store/opensearch_store.py

@@ -13,7 +13,7 @@ from lxml import etree
 
 from PyQt4.Qt import QUrl
 
-from calibre import browser
+from calibre import (browser, guess_extension)
 from calibre.gui2 import open_url
 from calibre.gui2.store import StorePlugin
 from calibre.gui2.store.search_result import SearchResult
@@ -81,7 +81,7 @@ class OpenSearchOPDSStore(StorePlugin):
                             s.detail_item = href
                         elif 'http://opds-spec.org/acquisition' in rel:
                             if type:
-                                ext = mimetypes.guess_extension(type)
+                                ext = guess_extension(type)
                                 if ext:
                                     ext = ext[1:].upper().strip()
                                     s.downloads[ext] = href