2 * Used by System.IO.Compression.DeflateStream
5 * Gonzalo Paniagua Javier (gonzalo@novell.com)
7 * (c) Copyright 2009 Novell, Inc.
10 #if defined (HAVE_ZLIB)
25 #define BUFFER_SIZE 4096
26 #define ARGUMENT_ERROR -10
29 typedef gint (*read_write_func) (guchar *buffer, gint length, void *gchandle);
38 typedef struct _ZStream ZStream;
40 ZStream *CreateZStream (gint compress, guchar gzip, read_write_func func, void *gchandle);
41 gint CloseZStream (ZStream *zstream);
42 gint Flush (ZStream *stream);
43 gint ReadZStream (ZStream *stream, guchar *buffer, gint length);
44 gint WriteZStream (ZStream *stream, guchar *buffer, gint length);
45 static gint flush_internal (ZStream *stream, gboolean is_final);
48 z_alloc (void *opaque, unsigned int nitems, unsigned int item_size)
50 return g_malloc0 (nitems * item_size);
54 z_free (void *opaque, void *ptr)
60 CreateZStream (gint compress, guchar gzip, read_write_func func, void *gchandle)
69 #if !defined(ZLIB_VERNUM) || (ZLIB_VERNUM < 0x1204)
70 /* Older versions of zlib do not support raw deflate or gzip */
74 z = g_new0 (z_stream, 1);
76 retval = deflateInit2 (z, Z_DEFAULT_COMPRESSION, Z_DEFLATED, gzip ? 31 : -15, 8, Z_DEFAULT_STRATEGY);
78 retval = inflateInit2 (z, gzip ? 31 : -15);
87 result = g_new0 (ZStream, 1);
90 result->gchandle = gchandle;
91 result->compress = compress;
92 result->buffer = g_new (guchar, BUFFER_SIZE);
93 result->stream->next_out = result->buffer;
94 result->stream->avail_out = BUFFER_SIZE;
99 CloseZStream (ZStream *zstream)
105 return ARGUMENT_ERROR;
108 if (zstream->compress) {
109 if (zstream->stream->total_in > 0) {
111 status = deflate (zstream->stream, Z_FINISH);
112 flush_status = flush_internal (zstream, TRUE);
113 } while (status == Z_OK); /* We want Z_STREAM_END or error here here */
114 if (status == Z_STREAM_END)
115 status = flush_status;
117 deflateEnd (zstream->stream);
119 inflateEnd (zstream->stream);
121 g_free (zstream->buffer);
122 g_free (zstream->stream);
123 memset (zstream, 0, sizeof (ZStream));
129 write_to_managed (ZStream *stream)
135 if (zs->avail_out != BUFFER_SIZE) {
136 n = stream->func (stream->buffer, BUFFER_SIZE - zs->avail_out, stream->gchandle);
137 zs->next_out = stream->buffer;
138 zs->avail_out = BUFFER_SIZE;
146 flush_internal (ZStream *stream, gboolean is_final)
150 if (!stream->compress)
153 if (!is_final && stream->stream->avail_in != 0) {
154 status = deflate (stream->stream, Z_PARTIAL_FLUSH);
155 if (status != Z_OK && status != Z_STREAM_END)
158 return write_to_managed (stream);
162 Flush (ZStream *stream)
164 return flush_internal (stream, FALSE);
168 ReadZStream (ZStream *stream, guchar *buffer, gint length)
174 if (stream == NULL || buffer == NULL || length < 0)
175 return ARGUMENT_ERROR;
181 zs->next_out = buffer;
182 zs->avail_out = length;
183 while (zs->avail_out > 0) {
184 if (zs->avail_in == 0) {
185 n = stream->func (stream->buffer, BUFFER_SIZE, stream->gchandle);
189 zs->next_in = stream->buffer;
193 if (zs->avail_in == 0 && zs->total_in == 0)
196 status = inflate (stream->stream, Z_SYNC_FLUSH);
197 if (status == Z_STREAM_END) {
200 } else if (status != Z_OK) {
204 return length - zs->avail_out;
208 WriteZStream (ZStream *stream, guchar *buffer, gint length)
214 if (stream == NULL || buffer == NULL || length < 0)
215 return ARGUMENT_ERROR;
221 zs->next_in = buffer;
222 zs->avail_in = length;
223 while (zs->avail_in > 0) {
224 if (zs->avail_out == 0) {
225 zs->next_out = stream->buffer;
226 zs->avail_out = BUFFER_SIZE;
228 status = deflate (stream->stream, Z_NO_FLUSH);
229 if (status != Z_OK && status != Z_STREAM_END)
232 if (zs->avail_out == 0) {
233 n = write_to_managed (stream);