[gimp] Avoid use of temporary files for accessing remote files

[Sven Neumann <neo src gnome org>]

commit 6fa2ece547efa1ad515648419f1444ce0b1e948a
Author: Sven Neumann <s neumann phase-zero de>
Date:   Tue Apr 21 17:48:17 2009 +0200

    Avoid use of temporary files for accessing remote files
    
    When using GIO/GVFS, remote files may have a local representation
    provided by a FUSE mount. Try to detect this and access the file
    directly instead of using a temporary file. Fallback to the old
    behavior of using temporary files if GIO can't give us a local path
    to the file.
---
 plug-ins/file-uri/uri-backend-gvfs.c    |   48 +++++++++++++++++++++++---
 plug-ins/file-uri/uri-backend-libcurl.c |    7 ++++
 plug-ins/file-uri/uri-backend-wget.c    |    7 ++++
 plug-ins/file-uri/uri-backend.h         |    2 +
 plug-ins/file-uri/uri.c                 |   56 +++++++++++++++++++++----------
 5 files changed, 96 insertions(+), 24 deletions(-)

diff --git a/plug-ins/file-uri/uri-backend-gvfs.c b/plug-ins/file-uri/uri-backend-gvfs.c
index 9554371..55cfb78 100644
--- a/plug-ins/file-uri/uri-backend-gvfs.c
+++ b/plug-ins/file-uri/uri-backend-gvfs.c
@@ -39,12 +39,14 @@ typedef enum
 } Mode;
 
 
-static gchar    * get_protocols (void);
-static gboolean   copy_uri      (const gchar  *src_uri,
-                                 const gchar  *dest_uri,
-                                 Mode          mode,
-                                 GimpRunMode   run_mode,
-                                 GError      **error);
+static gchar    * get_protocols          (void);
+static gboolean   copy_uri               (const gchar  *src_uri,
+                                          const gchar  *dest_uri,
+                                          Mode          mode,
+                                          GimpRunMode   run_mode,
+                                          GError      **error);
+static gboolean   mount_enclosing_volume (GFile        *file,
+                                          GError      **error);
 
 static gchar *supported_protocols = NULL;
 
@@ -138,6 +140,40 @@ uri_backend_save_image (const gchar  *uri,
   return FALSE;
 }
 
+gchar *
+uri_backend_map_image (const gchar  *uri,
+                       GimpRunMode   run_mode)
+{
+  GFile    *file    = g_file_new_for_uri (uri);
+  gchar    *path    = NULL;
+  gboolean  success = TRUE;
+
+  if (! file)
+    return NULL;
+
+  if (run_mode == GIMP_RUN_INTERACTIVE)
+    {
+      GError *error = NULL;
+
+      if (! mount_enclosing_volume (file, &error))
+        {
+
+          if (error->domain == G_IO_ERROR   &&
+              error->code   == G_IO_ERROR_ALREADY_MOUNTED)
+            success = TRUE;
+
+          g_error_free (error);
+        }
+    }
+
+  if (success)
+    path = g_file_get_path (file);
+
+  g_object_unref (file);
+
+  return path;
+}
+
 
 /*  private functions  */
 
diff --git a/plug-ins/file-uri/uri-backend-libcurl.c b/plug-ins/file-uri/uri-backend-libcurl.c
index 05de944..5632235 100644
--- a/plug-ins/file-uri/uri-backend-libcurl.c
+++ b/plug-ins/file-uri/uri-backend-libcurl.c
@@ -223,3 +223,10 @@ uri_backend_save_image (const gchar  *uri,
 
   return FALSE;
 }
+
+gchar *
+uri_backend_map_image (const gchar  *uri,
+                       GimpRunMode   run_mode)
+{
+  return NULL;
+}
diff --git a/plug-ins/file-uri/uri-backend-wget.c b/plug-ins/file-uri/uri-backend-wget.c
index 0cfc844..56bf75b 100644
--- a/plug-ins/file-uri/uri-backend-wget.c
+++ b/plug-ins/file-uri/uri-backend-wget.c
@@ -386,3 +386,10 @@ uri_backend_save_image (const gchar  *uri,
 
   return FALSE;
 }
+
+gchar *
+uri_backend_map_image (const gchar  *uri,
+                       GimpRunMode   run_mode)
+{
+  return NULL;
+}
diff --git a/plug-ins/file-uri/uri-backend.h b/plug-ins/file-uri/uri-backend.h
index b116cc4..1f634a1 100644
--- a/plug-ins/file-uri/uri-backend.h
+++ b/plug-ins/file-uri/uri-backend.h
@@ -39,6 +39,8 @@ gboolean      uri_backend_save_image         (const gchar  *uri,
                                               const gchar  *tmpname,
                                               GimpRunMode   run_mode,
                                               GError      **error);
+gchar       * uri_backend_map_image          (const gchar  *uri,
+                                              GimpRunMode   run_mode);
 
 
 #endif /* __URI_BACKEND_H__ */
diff --git a/plug-ins/file-uri/uri.c b/plug-ins/file-uri/uri.c
index c84ef7e..e458001 100644
--- a/plug-ins/file-uri/uri.c
+++ b/plug-ins/file-uri/uri.c
@@ -234,28 +234,40 @@ load_image (const gchar  *uri,
   gchar    *tmpname    = NULL;
   gint32    image_ID   = -1;
   gboolean  name_image = FALSE;
+  gboolean  mapped;
 
-  tmpname = get_temp_name (uri, &name_image);
+  tmpname = uri_backend_map_image (uri, run_mode);
 
-  if (uri_backend_load_image (uri, tmpname, run_mode, error))
+  if (tmpname)
     {
-      image_ID = gimp_file_load (run_mode, tmpname, tmpname);
+      mapped = TRUE;
+    }
+  else
+    {
+      tmpname = get_temp_name (uri, &name_image);
 
-      if (image_ID != -1)
-        {
-          if (name_image)
-            gimp_image_set_filename (image_ID, uri);
-          else
-            gimp_image_set_filename (image_ID, "");
-        }
+      if (! uri_backend_load_image (uri, tmpname, run_mode, error))
+        return -1;
+    }
+
+  image_ID = gimp_file_load (run_mode, tmpname, tmpname);
+
+  if (image_ID != -1)
+    {
+      if (mapped || name_image)
+        gimp_image_set_filename (image_ID, uri);
       else
-        {
-          g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
-                       "%s", gimp_get_pdb_error ());
-        }
+        gimp_image_set_filename (image_ID, "");
     }
+  else
+    {
+      g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
+                   "%s", gimp_get_pdb_error ());
+    }
+
+  if (! mapped)
+    g_unlink (tmpname);
 
-  g_unlink (tmpname);
   g_free (tmpname);
 
   return image_ID;
@@ -270,8 +282,14 @@ save_image (const gchar  *uri,
 {
   GimpPDBStatusType  status = GIMP_PDB_EXECUTION_ERROR;
   gchar             *tmpname;
+  gboolean           mapped;
 
-  tmpname = get_temp_name (uri, NULL);
+  tmpname = uri_backend_map_image (uri, run_mode);
+
+  if (tmpname)
+    mapped = TRUE;
+  else
+    tmpname = get_temp_name (uri, NULL);
 
   if (gimp_file_save (run_mode,
                       image_ID,
@@ -279,7 +297,7 @@ save_image (const gchar  *uri,
                       tmpname,
                       tmpname) && valid_file (tmpname))
     {
-      if (uri_backend_save_image (uri, tmpname, run_mode, error))
+      if (mapped || uri_backend_save_image (uri, tmpname, run_mode, error))
         {
           status = GIMP_PDB_SUCCESS;
         }
@@ -290,7 +308,9 @@ save_image (const gchar  *uri,
                    "%s", gimp_get_pdb_error ());
     }
 
-  g_unlink (tmpname);
+  if (! mapped)
+    g_unlink (tmpname);
+
   g_free (tmpname);
 
   return status;