libswfdec/swfdec_amf.c

   1 /* Swfdec
   2  * Copyright (C) 2007 Benjamin Otte <otte@gnome.org>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301  USA
  18  */
  19
  20 #ifndef HAVE_CONFIG_H
  21 #include "config.h"
  22 #endif
  23
  24 #include "swfdec_amf.h"
  25 #include "swfdec_as_array.h"
  26 #include "swfdec_debug.h"
  27
  28 typedef gboolean (* SwfdecAmfParseFunc) (SwfdecAsContext *cx, SwfdecBits *bits, SwfdecAsValue *val);
  29 extern const SwfdecAmfParseFunc parse_funcs[SWFDEC_AMF_N_TYPES];
  30
  31 static gboolean
  32 swfdec_amf_parse_boolean (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  33 {
  34   SWFDEC_AS_VALUE_SET_BOOLEAN (val, swfdec_bits_get_u8 (bits) ? TRUE : FALSE);
  35   return TRUE;
  36 }
  37
  38 static gboolean
  39 swfdec_amf_parse_number (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  40 {
  41   SWFDEC_AS_VALUE_SET_NUMBER (val, swfdec_bits_get_bdouble (bits));
  42   return TRUE;
  43 }
  44
  45 static gboolean
  46 swfdec_amf_parse_string (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  47 {
  48   guint len = swfdec_bits_get_bu16 (bits);
  49   char *s;
  50
  51   /* FIXME: the supplied version is likely incorrect */
  52   s = swfdec_bits_get_string_length (bits, len, context->version);
  53   if (s == NULL)
  54     return FALSE;
  55   SWFDEC_AS_VALUE_SET_STRING (val, swfdec_as_context_give_string (context, s));
  56   return TRUE;
  57 }
  58
  59 static gboolean
  60 swfdec_amf_parse_properties (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsObject *object)
  61 {
  62   guint type;
  63   SwfdecAmfParseFunc func;
  64
  65   while (swfdec_bits_left (bits)) {
  66     SwfdecAsValue val;
  67     const char *name;
  68
  69     if (!swfdec_amf_parse_string (context, bits, &val))
  70       return FALSE;
  71     name = SWFDEC_AS_VALUE_GET_STRING (&val);
  72     type = swfdec_bits_get_u8 (bits);
  73     if (type == SWFDEC_AMF_END_OBJECT)
  74       break;
  75     if (type >= SWFDEC_AMF_N_TYPES ||
  76         (func = parse_funcs[type]) == NULL) {
  77       SWFDEC_ERROR ("no parse func for AMF type %u", type);
  78       goto error;
  79     }
  80     swfdec_as_object_set_variable (object, name, &val); /* GC... */
  81     if (!func (context, bits, &val)) {
  82       goto error;
  83     }
  84     swfdec_as_object_set_variable (object, name, &val);
  85   }
  86   /* no more bytes seems to end automatically */
  87   return TRUE;
  88
  89 error:
  90   return FALSE;
  91 }
  92
  93 static gboolean
  94 swfdec_amf_parse_object (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  95 {
  96   SwfdecAsObject *object;
  97
  98   object = swfdec_as_object_new (context);
  99   if (object == NULL)
 100     return FALSE;
 101   if (!swfdec_amf_parse_properties (context, bits, object))
 102     return FALSE;
 103   SWFDEC_AS_VALUE_SET_OBJECT (val, object);
 104   return TRUE;
 105 }
 106
 107 static gboolean
 108 swfdec_amf_parse_mixed_array (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
 109 {
 110   guint len;
 111   SwfdecAsObject *array;
 112
 113   len = swfdec_bits_get_bu32 (bits);
 114   array = swfdec_as_array_new (context);
 115   if (array == NULL)
 116     return FALSE;
 117   if (!swfdec_amf_parse_properties (context, bits, array))
 118     return FALSE;
 119   SWFDEC_AS_VALUE_SET_OBJECT (val, array);
 120   return TRUE;
 121 }
 122
 123 static gboolean
 124 swfdec_amf_parse_array (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
 125 {
 126   guint i, len;
 127   SwfdecAsObject *array;
 128   guint type;
 129   SwfdecAmfParseFunc func;
 130
 131   len = swfdec_bits_get_bu32 (bits);
 132   array = swfdec_as_array_new (context);
 133   if (array == NULL)
 134     return FALSE;
 135   for (i = 0; i < len; i++) {
 136     SwfdecAsValue tmp;
 137     type = swfdec_bits_get_u8 (bits);
 138     if (type >= SWFDEC_AMF_N_TYPES ||
 139         (func = parse_funcs[type]) == NULL) {
 140       SWFDEC_ERROR ("no parse func for AMF type %u", type);
 141       goto fail;
 142     }
 143     if (!func (context, bits, &tmp))
 144       goto fail;
 145     swfdec_as_array_push (SWFDEC_AS_ARRAY (array), &tmp);
 146   }
 147
 148   SWFDEC_AS_VALUE_SET_OBJECT (val, array);
 149   return TRUE;
 150
 151 fail:
 152   return FALSE;
 153 }
 154
 155 const SwfdecAmfParseFunc parse_funcs[SWFDEC_AMF_N_TYPES] = {
 156   [SWFDEC_AMF_NUMBER] = swfdec_amf_parse_number,
 157   [SWFDEC_AMF_BOOLEAN] = swfdec_amf_parse_boolean,
 158   [SWFDEC_AMF_STRING] = swfdec_amf_parse_string,
 159   [SWFDEC_AMF_OBJECT] = swfdec_amf_parse_object,
 160   [SWFDEC_AMF_MIXED_ARRAY] = swfdec_amf_parse_mixed_array,
 161   [SWFDEC_AMF_ARRAY] = swfdec_amf_parse_array,
 162 #if 0
 163   SWFDEC_AMF_MOVIECLIP = 4,
 164   SWFDEC_AMF_NULL = 5,
 165   SWFDEC_AMF_UNDEFINED = 6,
 166   SWFDEC_AMF_REFERENCE = 7,
 167   SWFDEC_AMF_END_OBJECT = 9,
 168   SWFDEC_AMF_ARRAY = 10,
 169   SWFDEC_AMF_DATE = 11,
 170   SWFDEC_AMF_BIG_STRING = 12,
 171   SWFDEC_AMF_RECORDSET = 14,
 172   SWFDEC_AMF_XML = 15,
 173   SWFDEC_AMF_CLASS = 16,
 174   SWFDEC_AMF_FLASH9 = 17,
 175 #endif
 176 };
 177
 178 gboolean
 179 swfdec_amf_parse_one (SwfdecAsContext *context, SwfdecBits *bits,
 180     SwfdecAmfType expected_type, SwfdecAsValue *rval)
 181 {
 182   SwfdecAmfParseFunc func;
 183   guint type;
 184
 185   g_return_val_if_fail (SWFDEC_IS_AS_CONTEXT (context), 0);
 186   g_return_val_if_fail (bits != NULL, FALSE);
 187   g_return_val_if_fail (rval != NULL, FALSE);
 188   g_return_val_if_fail (expected_type < SWFDEC_AMF_N_TYPES, FALSE);
 189
 190   type = swfdec_bits_get_u8 (bits);
 191   if (type != expected_type) {
 192     SWFDEC_ERROR ("parse object should be type %u, but is %u",
 193         expected_type, type);
 194     return FALSE;
 195   }
 196   if (type >= SWFDEC_AMF_N_TYPES ||
 197       (func = parse_funcs[type]) == NULL) {
 198     SWFDEC_ERROR ("no parse func for AMF type %u", type);
 199     return FALSE;
 200   }
 201   return func (context, bits, rval);
 202 }
 203
 204 guint
 205 swfdec_amf_parse (SwfdecAsContext *context, SwfdecBits *bits, guint n_items, ...)
 206 {
 207   va_list args;
 208   guint i;
 209
 210   g_return_val_if_fail (SWFDEC_IS_AS_CONTEXT (context), 0);
 211   g_return_val_if_fail (bits != NULL, 0);
 212
 213   va_start (args, n_items);
 214   for (i = 0; i < n_items; i++) {
 215     SwfdecAmfType type = va_arg (args, SwfdecAmfType);
 216     SwfdecAsValue *val = va_arg (args, SwfdecAsValue *);
 217     if (!swfdec_amf_parse_one (context, bits, type, val))
 218       break;
 219   }
 220   va_end (args);
 221   return i;
 222 }
 223