1 files changed, 149 insertions, 0 deletions
diff --git a/src/streams-gzip.cpp b/src/streams-gzip.cpp
new file mode 100644
index 000000000..c2cda1c2b
--- /dev/null
+++ b/src/streams-gzip.cpp
@@ -0,0 +1,149 @@
+/*
+ * IO layer : gzip streambuf and streams
+ *
+ * Authors:
+ *   Johan Ceuppens <jceuppen at easynet dot be>
+ *
+ * Copyright (C) 2004 Johan Ceuppens
+ *
+ * Released under GNU LGPL, read the file 'COPYING.LIB' for more information
+ */
+
+#include "streams-gzip.h"
+
+namespace Inkscape {
+
+//With some inpsiration and code from libgsf, fastjar, libpng and RFC 1952
+
+static int const GZIP_IS_ASCII	     = 0x01; //file contains text
+static int const GZIP_HEADER_CRC     = 0x02; //there is a CRC in the header
+static int const GZIP_EXTRA_FIELD    = 0x04; //there is an 'extra' field
+static int const GZIP_ORIGINAL_NAME  = 0x08; //the original is stored
+static int const GZIP_HAS_COMMENT    = 0x10; //There is a comment in the header 
+static unsigned int const GZIP_HEADER_FLAGS = (GZIP_IS_ASCII 
+					       |GZIP_HEADER_CRC 
+					       |GZIP_EXTRA_FIELD
+					       |GZIP_ORIGINAL_NAME
+					       |GZIP_HAS_COMMENT);
+
+/**
+ * GZipBuffer
+ */
+
+void GZipBuffer::consume_header() throw(GZipHeaderException)
+{
+    unsigned int flags;
+    guint8 data[4];
+    
+    try {
+	_urihandle->read(data, 4);
+	check_signature(data);
+	check_flags(data);
+	flags = data[3];
+	_urihandle->read(data, 4);
+	//get_modification_time()
+	_urihandle->read(data, 1);
+	//check_extra_flags();
+	_urihandle->read(data, 1);
+	//check_OS();
+	
+	if (flags & GZIP_EXTRA_FIELD) {
+	    get_extrafield();
+	}
+	if (flags & GZIP_ORIGINAL_NAME) {
+	    get_filename();
+	}
+	if (flags & GZIP_HAS_COMMENT) {
+	    get_comment();
+	}
+	if (flags & GZIP_HEADER_CRC) {
+	    get_crc();
+	}
+    }
+    catch(std::exception& e) {
+	throw GZipHeaderException();
+    }
+}
+
+void GZipBuffer::check_signature(guint8 *data) throw(GZipHeaderException)
+{
+    guint8 const signature[2] = {0x1f, 0x8b};
+    if (memcmp(data, signature, sizeof(signature)) != 0)
+	throw GZipHeaderException();
+}
+
+void GZipBuffer::check_flags(guint8 *data) throw(GZipHeaderException)
+{
+    unsigned int flags = data[3];
+    if (data[2] != Z_DEFLATED || (flags & ~GZIP_HEADER_FLAGS) != 0)
+	throw GZipHeaderException();
+}
+
+gchar *GZipBuffer::get_filename()
+{
+#ifdef DEBUG_STREAMS
+    std::cout<<"Filename is ";
+#endif
+    return read_string();
+}
+
+gchar *GZipBuffer::get_comment()
+{
+#ifdef DEBUG_STREAMS
+    std::cout<<"Comment is "<<std::endl;
+#endif
+    return read_string();
+}
+
+guint16 GZipBuffer::get_crc()
+{
+    guint16 buf;
+    _urihandle->read(&buf, 2);
+    return buf;
+}
+
+void GZipBuffer::get_extrafield()
+{
+    guint8 length_data[2];
+    _urihandle->read(length_data, 2);
+    unsigned int const length = length_data[0] | (length_data[1] << 8);
+    guint8 *data = new guint8[length];
+    _urihandle->read(data, length);
+}
+
+gchar *GZipBuffer::read_string() throw(GZipHeaderException)
+{
+    GByteArray *gba = g_byte_array_new();
+    try {
+	guint8 byte[1];
+	do {
+	    _urihandle->read(byte, 1);
+	    g_byte_array_append(gba, byte, sizeof(byte));
+#ifdef DEBUG_STREAMS
+	    std::cout <<(char)*byte;
+#endif
+	} while (*byte != 0);
+    } catch (std::exception& e) {
+	g_byte_array_free(gba, TRUE);
+	throw GZipHeaderException();
+    }
+#ifdef DEBUG_STREAMS
+    std::cout<<std::endl;
+#endif
+    gchar *ret = (gchar *)gba->data;
+    g_byte_array_free(gba, FALSE);
+    return ret;
+}
+
+} // namespace Inkscape
+
+/*
+  Local Variables:
+  mode:c++
+  c-file-style:"stroustrup"
+  c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
+  indent-tabs-mode:nil
+  fill-column:99
+  End:
+*/
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :