method to stream data content in a buffer.

1999-05-08  bertrand <Bertrand.Guiheneuf@inria.fr>

	* camel/camel-data-wrapper.c
	(camel_data_wrapper_write_to_buffer): method to
	stream data content in a buffer.
	(camel_data_wrapper_write_to_file):
	(camel_data_wrapper_construct_from_buffer):
	(camel_data_wrapper_construct_from_file):
	new methods.

Basic data_wrapper interface. Will have to add MIME content
type and bonobo object creation from content type.

Bertrand.

diff --git a/camel/camel-data-wrapper.c b/camel/camel-data-wrapper.c
index 19abc31..9020b7e 100644 (file)
--- a/camel/camel-data-wrapper.c
+++ b/camel/camel-data-wrapper.c
@@ -1,5 +1,8 @@
 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
-/* camelDataWrapper.c : Abstract class for an data_wrapper */
+/* camelDataWrapper.c : Abstract class for a data_wrapper */
+
+/** THIS IS MOSTLY AN ABSTRACT CLASS THAT SHOULD HAVE BEEN AN
+    INTERFACE. **/
 
 /* 
  *
@@ -28,12 +31,21 @@ static GtkObjectClass *parent_class=NULL;
 /* Returns the class for a CamelDataWrapper */
 #define CDH_CLASS(so) CAMEL_DATA_WRAPPER_CLASS (GTK_OBJECT(so)->klass)
 
+static void __camel_data_wrapper_write_to_buffer(CamelDataWrapper *data_wrapper, gchar *buffer);
+static void __camel_data_wrapper_write_to_file(CamelDataWrapper *data_wrapper, FILE *file);
+static void __camel_data_wrapper_construct_from_buffer(CamelDataWrapper *data_wrapper, gchar *buffer, guint size);
+static void __camel_data_wrapper_construct_from_file (CamelDataWrapper *data_wrapper, FILE *file, guint size);
+
 static void
 camel_data_wrapper_class_init (CamelDataWrapperClass *camel_data_wrapper_class)
 {
        parent_class = gtk_type_class (gtk_object_get_type ());
        
        /* virtual method definition */
+       camel_data_wrapper_class->write_to_buffer = __camel_data_wrapper_write_to_buffer;
+       camel_data_wrapper_class->write_to_file = __camel_data_wrapper_write_to_file;
+       camel_data_wrapper_class->construct_from_buffer = __camel_data_wrapper_construct_from_buffer;
+       camel_data_wrapper_class->construct_from_file = __camel_data_wrapper_construct_from_file;
 
        /* virtual method overload */
 }
@@ -70,3 +82,93 @@ camel_data_wrapper_get_type (void)
 
 
 
+
+/**
+ * __camel_data_wrapper_write_to_buffer: write data content in a byte buffer
+ * @data_wrapper: the data wrapper object
+ * @buffer: byte buffer where data will be written 
+ * 
+ * This method must be overriden by subclasses
+ * Data must be written in the bytes buffer
+ * in a architecture independant fashion. 
+ * If data is a standard data (for example an jpg image)
+ * it must be serialized in the buffer exactly as it 
+ * would be saved on disk. A simple dump of the buffer in
+ * a file should be sufficient for the data to be 
+ * re-read by a foreign application.  
+ * 
+ **/
+static void
+__camel_data_wrapper_write_to_buffer(CamelDataWrapper *data_wrapper, gchar *buffer)
+{
+       /* nothing */
+}
+
+
+/**
+ * camel_data_wrapper_write_to_buffer: write data in a memory buffer
+ * @data_wrapper: the data wrapper object
+ * @buffer: byte buffer where data will be written 
+ *
+ * Write data content in a buffer. Data is stored in a machine
+ * independant format. 
+ * 
+ **/
+void 
+camel_data_wrapper_write_to_buffer(CamelDataWrapper *data_wrapper, gchar *buffer)
+{
+       CDH_CLASS(data_wrapper)->write_to_buffer (data_wrapper, buffer);
+}
+
+
+
+static void
+__camel_data_wrapper_write_to_file(CamelDataWrapper *data_wrapper, FILE *file)
+{
+       /* nothing */
+}
+
+
+/**
+ * camel_data_wrapper_write_to_file: write data in a binary file
+ * @data_wrapper: the data wrapper object
+ * @file: file descriptoe where to write data
+ * 
+ * Write data content in a binary file.  
+ *
+ **/
+void 
+camel_data_wrapper_write_to_file(CamelDataWrapper *data_wrapper, FILE *file)
+{
+       CDH_CLASS(data_wrapper)->write_to_file (data_wrapper, file);
+}
+
+
+static void
+__camel_data_wrapper_construct_from_buffer(CamelDataWrapper *data_wrapper, gchar *buffer, guint size)
+{
+       /* nothing */
+}
+
+void 
+camel_data_wrapper_construct_from_buffer(CamelDataWrapper *data_wrapper, gchar *buffer, guint size)
+{
+       CDH_CLASS(data_wrapper)->construct_from_buffer (data_wrapper, buffer, size);
+}
+
+
+
+static void
+__camel_data_wrapper_construct_from_file (CamelDataWrapper *data_wrapper, FILE *file, guint size)
+{
+       /* nothing */
+}
+
+void 
+camel_data_wrapper_construct_from_file (CamelDataWrapper *data_wrapper, FILE *file, guint size)
+{
+       CDH_CLASS(data_wrapper)->construct_from_file (data_wrapper, file, size);
+}
+
+
+

diff --git a/camel/camel-data-wrapper.h b/camel/camel-data-wrapper.h
index ef3a7cd..e6b0b2a 100644 (file)
--- a/camel/camel-data-wrapper.h
+++ b/camel/camel-data-wrapper.h
@@ -1,4 +1,5 @@
-/* camelDataWrapper.h : Abstract class for a datawrapper */
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/* camelDataWrapper.h : Abstract class for a data wrapper */
 
 /* 
  *
@@ -31,6 +32,7 @@ extern "C" {
 #endif /* __cplusplus }*/
 
 #include <gtk/gtk.h>
+#include <stdio.h>
 
 
 
@@ -51,8 +53,12 @@ typedef struct
 
 typedef struct {
        GtkObjectClass parent_class;
-
+       
        /* Virtual methods */   
+       void  (*write_to_buffer) (CamelDataWrapper *data_wrapper, gchar *buffer);
+       void  (*write_to_file) (CamelDataWrapper *data_wrapper, FILE *file);
+       void  (*construct_from_buffer) (CamelDataWrapper *data_wrapper, gchar *buffer, guint size);
+       void  (*construct_from_file) (CamelDataWrapper *data_wrapper, FILE *file, guint size);
 
 } CamelDataWrapperClass;
 
@@ -63,7 +69,10 @@ GtkType camel_data_wrapper_get_type (void);
 
 
 /* public methods */
-
+void camel_data_wrapper_write_to_buffer(CamelDataWrapper *data_wrapper, gchar *buffer);
+void camel_data_wrapper_write_to_file(CamelDataWrapper *data_wrapper, FILE *file);
+void camel_data_wrapper_construct_from_buffer(CamelDataWrapper *data_wrapper, gchar *buffer, guint size);
+void camel_data_wrapper_construct_from_file (CamelDataWrapper *data_wrapper, FILE *file, guint size);
 
 #ifdef __cplusplus
 }