libsoup/soup-coding-gzip.c

   1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
   2 /*
   3  * soup-coding-gzip.c: "gzip" coding
   4  *
   5  * Copyright (C) 2005 Novell, Inc.
   6  * Copyright (C) 2008 Red Hat, Inc.
   7  */
   8
   9 #ifdef HAVE_CONFIG_H
  10 #include <config.h>
  11 #endif
  12
  13 #include "soup-coding-gzip.h"
  14
  15 #include <zlib.h>
  16
  17 typedef struct {
  18         z_stream stream;
  19
  20 } SoupCodingGzipPrivate;
  21 #define SOUP_CODING_GZIP_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), SOUP_TYPE_CODING_GZIP, SoupCodingGzipPrivate))
  22
  23 G_DEFINE_TYPE (SoupCodingGzip, soup_coding_gzip, SOUP_TYPE_CODING)
  24
  25 static void             constructed (GObject *object);
  26 static void             finalize    (GObject *object);
  27 static SoupCodingStatus apply_into  (SoupCoding *coding,
  28                                      gconstpointer input, gsize input_length,
  29                                      gsize *input_used,
  30                                      gpointer output, gsize output_length,
  31                                      gsize *output_used,
  32                                      gboolean done, GError **error);
  33
  34 static void
  35 soup_coding_gzip_init (SoupCodingGzip *gzip)
  36 {
  37         SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (gzip);
  38
  39         priv->stream.zalloc = Z_NULL;
  40         priv->stream.zfree = Z_NULL;
  41         priv->stream.opaque = Z_NULL;
  42 }
  43
  44 static void
  45 soup_coding_gzip_class_init (SoupCodingGzipClass *gzip_class)
  46 {
  47         GObjectClass *object_class = G_OBJECT_CLASS (gzip_class);
  48         SoupCodingClass *coding_class = SOUP_CODING_CLASS (gzip_class);
  49
  50         g_type_class_add_private (gzip_class, sizeof (SoupCodingGzipPrivate));
  51
  52         coding_class->name = "gzip";
  53
  54         object_class->constructed = constructed;
  55         object_class->finalize = finalize;
  56
  57         coding_class->apply_into = apply_into;
  58 }
  59
  60 static void
  61 constructed (GObject *object)
  62 {
  63         SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (object);
  64
  65         /* All of these values are the defaults according to the zlib
  66          * documentation. "16" is a magic number that means gzip
  67          * instead of zlib.
  68          */
  69         if (SOUP_CODING (object)->direction == SOUP_CODING_ENCODE) {
  70                 deflateInit2 (&priv->stream, Z_DEFAULT_COMPRESSION,
  71                               Z_DEFLATED, MAX_WBITS | 16, 8,
  72                               Z_DEFAULT_STRATEGY);
  73         } else
  74                 inflateInit2 (&priv->stream, MAX_WBITS | 16);
  75 }
  76
  77 static void
  78 finalize (GObject *object)
  79 {
  80         SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (object);
  81
  82         if (SOUP_CODING (object)->direction == SOUP_CODING_ENCODE)
  83                 deflateEnd (&priv->stream);
  84         else
  85                 inflateEnd (&priv->stream);
  86
  87         G_OBJECT_CLASS (soup_coding_gzip_parent_class)->finalize (object);
  88 }
  89
  90 static SoupCodingStatus
  91 apply_into (SoupCoding *coding,
  92             gconstpointer input, gsize input_length, gsize *input_used,
  93             gpointer output, gsize output_length, gsize *output_used,
  94             gboolean done, GError **error)
  95 {
  96         SoupCodingGzipPrivate *priv = SOUP_CODING_GZIP_GET_PRIVATE (coding);
  97         int ret;
  98
  99         priv->stream.avail_in = input_length;
 100         priv->stream.next_in  = (gpointer)input;
 101         priv->stream.total_in = 0;
 102
 103         priv->stream.avail_out = output_length;
 104         priv->stream.next_out  = output;
 105         priv->stream.total_out = 0;
 106
 107         if (coding->direction == SOUP_CODING_ENCODE)
 108                 ret = deflate (&priv->stream, done ? Z_FINISH : Z_NO_FLUSH);
 109         else
 110                 ret = inflate (&priv->stream, Z_SYNC_FLUSH);
 111
 112         *input_used = priv->stream.total_in;
 113         *output_used = priv->stream.total_out;
 114
 115         switch (ret) {
 116         case Z_NEED_DICT:
 117         case Z_DATA_ERROR:
 118         case Z_STREAM_ERROR:
 119                 g_set_error_literal (error, SOUP_CODING_ERROR,
 120                                      SOUP_CODING_ERROR_DATA_ERROR,
 121                                      priv->stream.msg ? priv->stream.msg : "Bad data");
 122                 return SOUP_CODING_STATUS_ERROR;
 123
 124         case Z_BUF_ERROR:
 125         case Z_MEM_ERROR:
 126                 g_set_error_literal (error, SOUP_CODING_ERROR,
 127                                      SOUP_CODING_ERROR_INTERNAL_ERROR,
 128                                      priv->stream.msg ? priv->stream.msg : "Internal error");
 129                 return SOUP_CODING_STATUS_ERROR;
 130
 131         case Z_STREAM_END:
 132                 /* Discard any trailing junk, for compatibility with
 133                  * other browsers. FIXME: this really belongs in
 134                  * soup-message-io, but it's not possible to do there
 135                  * with the current API.
 136                  */
 137                 *input_used = input_length;
 138                 return SOUP_CODING_STATUS_COMPLETE;
 139
 140         case Z_OK:
 141         default:
 142                 if (*output_used == output_length &&
 143                     *input_used < input_length)
 144                         return SOUP_CODING_STATUS_NEED_SPACE;
 145                 else
 146                         return SOUP_CODING_STATUS_OK;
 147         }
 148 }