Content-Encoding support

Adds SoupContentDecoder, which provides support for decoding "gzip"
Content-Encoding. For now other types are not supported and can't be
added. The SoupCoding interface is private because it will eventually
be replaced with something GConverter-based.

https://bugzilla.gnome.org/show_bug.cgi?id=522772

1 files changed, 142 insertions, 0 deletions

diff --git a/libsoup/soup-coding-gzip.c b/libsoup/soup-coding-gzip.c
new file mode 100644
index 00000000..b1731d57
--- /dev/null
+++ b/libsoup/soup-coding-gzip.c
@@ -0,0 +1,142 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * soup-coding-gzip.c: "gzip" coding
+ *
+ * Copyright (C) 2005 Novell, Inc.
+ * Copyright (C) 2008 Red Hat, Inc.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "soup-coding-gzip.h"
+
+#include <zlib.h>
+
+typedef struct {
+	z_stream stream;
+
+} SoupCodingGzipPrivate;
+#define SOUP_CODING_GZIP_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), SOUP_TYPE_CODING_GZIP, SoupCodingGzipPrivate))
+
+G_DEFINE_TYPE (SoupCodingGzip, soup_coding_gzip, SOUP_TYPE_CODING)
+
+static void             constructed (GObject *object);
+static void             finalize    (GObject *object);
+static SoupCodingStatus apply_into  (SoupCoding *coding,
+				     gconstpointer input, gsize input_length,
+				     gsize *input_used,
+				     gpointer output, gsize output_length,
+				     gsize *output_used,
+				     gboolean done, GError **error);
+
+static void
+soup_coding_gzip_init (SoupCodingGzip *gzip)
+{
+	SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (gzip);
+
+	priv->stream.zalloc = Z_NULL;
+	priv->stream.zfree = Z_NULL;
+	priv->stream.opaque = Z_NULL;
+}
+
+static void
+soup_coding_gzip_class_init (SoupCodingGzipClass *gzip_class)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS (gzip_class);
+	SoupCodingClass *coding_class = SOUP_CODING_CLASS (gzip_class);
+
+	g_type_class_add_private (gzip_class, sizeof (SoupCodingGzipPrivate));
+
+	coding_class->name = "gzip";
+
+	object_class->constructed = constructed;
+	object_class->finalize = finalize;
+
+	coding_class->apply_into = apply_into;
+}
+
+static void
+constructed (GObject *object)
+{
+	SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (object);
+
+	/* All of these values are the defaults according to the zlib
+	 * documentation. "16" is a magic number that means gzip
+	 * instead of zlib.
+	 */
+	if (SOUP_CODING (object)->direction == SOUP_CODING_ENCODE) {
+		deflateInit2 (&priv->stream, Z_DEFAULT_COMPRESSION,
+			      Z_DEFLATED, MAX_WBITS | 16, 8,
+			      Z_DEFAULT_STRATEGY);
+	} else
+		inflateInit2 (&priv->stream, MAX_WBITS | 16);
+}
+
+static void
+finalize (GObject *object)
+{
+	SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (object);
+
+	if (SOUP_CODING (object)->direction == SOUP_CODING_ENCODE)
+		deflateEnd (&priv->stream);
+	else
+		inflateEnd (&priv->stream);
+
+	G_OBJECT_CLASS (soup_coding_gzip_parent_class)->finalize (object);
+}
+
+static SoupCodingStatus
+apply_into (SoupCoding *coding,
+	    gconstpointer input, gsize input_length, gsize *input_used,
+	    gpointer output, gsize output_length, gsize *output_used,
+	    gboolean done, GError **error)
+{
+	SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (coding);
+	int ret;
+
+	priv->stream.avail_in = input_length;
+	priv->stream.next_in  = (gpointer)input;
+	priv->stream.total_in = 0;
+
+	priv->stream.avail_out = output_length;
+	priv->stream.next_out  = output;
+	priv->stream.total_out = 0;
+
+	if (coding->direction == SOUP_CODING_ENCODE)
+		ret = deflate (&priv->stream, done ? Z_FINISH : Z_NO_FLUSH);
+	else
+		ret = inflate (&priv->stream, Z_SYNC_FLUSH);
+
+	*input_used = priv->stream.total_in;
+	*output_used = priv->stream.total_out;
+
+	switch (ret) {
+	case Z_NEED_DICT:
+	case Z_DATA_ERROR:
+	case Z_STREAM_ERROR:
+		g_set_error_literal (error, SOUP_CODING_ERROR,
+				     SOUP_CODING_ERROR_DATA_ERROR,
+				     priv->stream.msg ? priv->stream.msg : "Bad data");
+		return SOUP_CODING_STATUS_ERROR;
+
+	case Z_BUF_ERROR:
+	case Z_MEM_ERROR:
+		g_set_error_literal (error, SOUP_CODING_ERROR,
+				     SOUP_CODING_ERROR_INTERNAL_ERROR,
+				     priv->stream.msg ? priv->stream.msg : "Internal error");
+		return SOUP_CODING_STATUS_ERROR;
+
+	case Z_STREAM_END:
+		return SOUP_CODING_STATUS_COMPLETE;
+
+	case Z_OK:
+	default:
+		if (*output_used == output_length &&
+		    *input_used < input_length)
+			return SOUP_CODING_STATUS_NEED_SPACE;
+		else
+			return SOUP_CODING_STATUS_OK;
+	}
+}