swfdec/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_as_date.h"
  27 #include "swfdec_debug.h"
  28
  29 typedef gboolean (* SwfdecAmfParseFunc) (SwfdecAsContext *cx, SwfdecBits *bits, SwfdecAsValue *val);
  30 extern const SwfdecAmfParseFunc parse_funcs[SWFDEC_AMF_N_TYPES];
  31
  32 static gboolean
  33 swfdec_amf_parse_boolean (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  34 {
  35   SWFDEC_AS_VALUE_SET_BOOLEAN (val, swfdec_bits_get_u8 (bits) ? TRUE : FALSE);
  36   return TRUE;
  37 }
  38
  39 static gboolean
  40 swfdec_amf_parse_number (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  41 {
  42   SWFDEC_AS_VALUE_SET_NUMBER (val, swfdec_bits_get_bdouble (bits));
  43   return TRUE;
  44 }
  45
  46 static gboolean
  47 swfdec_amf_parse_string (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  48 {
  49   guint len = swfdec_bits_get_bu16 (bits);
  50   char *s;
  51
  52   /* FIXME: the supplied version is likely incorrect */
  53   s = swfdec_bits_get_string_length (bits, len, context->version);
  54   if (s == NULL)
  55     return FALSE;
  56   SWFDEC_AS_VALUE_SET_STRING (val, swfdec_as_context_give_string (context, s));
  57   return TRUE;
  58 }
  59
  60 static gboolean
  61 swfdec_amf_parse_properties (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsObject *object)
  62 {
  63   guint type;
  64   SwfdecAmfParseFunc func;
  65
  66   while (swfdec_bits_left (bits)) {
  67     SwfdecAsValue val;
  68     const char *name;
  69
  70     if (!swfdec_amf_parse_string (context, bits, &val))
  71       return FALSE;
  72     name = SWFDEC_AS_VALUE_GET_STRING (&val);
  73     type = swfdec_bits_get_u8 (bits);
  74     if (type == SWFDEC_AMF_END_OBJECT)
  75       break;
  76     if (type >= SWFDEC_AMF_N_TYPES ||
  77         (func = parse_funcs[type]) == NULL) {
  78       SWFDEC_ERROR ("no parse func for AMF type %u", type);
  79       goto error;
  80     }
  81     swfdec_as_object_set_variable (object, name, &val); /* GC... */
  82     if (!func (context, bits, &val)) {
  83       goto error;
  84     }
  85     swfdec_as_object_set_variable (object, name, &val);
  86   }
  87   /* no more bytes seems to end automatically */
  88   return TRUE;
  89
  90 error:
  91   return FALSE;
  92 }
  93
  94 static gboolean
  95 swfdec_amf_parse_object (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
  96 {
  97   SwfdecAsObject *object;
  98
  99   object = swfdec_as_object_new (context);
 100   if (!swfdec_amf_parse_properties (context, bits, object))
 101     return FALSE;
 102   SWFDEC_AS_VALUE_SET_OBJECT (val, object);
 103   return TRUE;
 104 }
 105
 106 static gboolean
 107 swfdec_amf_parse_mixed_array (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
 108 {
 109   guint len;
 110   SwfdecAsObject *array;
 111
 112   len = swfdec_bits_get_bu32 (bits);
 113   array = swfdec_as_array_new (context);
 114   if (!swfdec_amf_parse_properties (context, bits, array))
 115     return FALSE;
 116   SWFDEC_AS_VALUE_SET_OBJECT (val, array);
 117   return TRUE;
 118 }
 119
 120 static gboolean
 121 swfdec_amf_parse_array (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
 122 {
 123   guint i, len;
 124   SwfdecAsObject *array;
 125   guint type;
 126   SwfdecAmfParseFunc func;
 127
 128   len = swfdec_bits_get_bu32 (bits);
 129   array = swfdec_as_array_new (context);
 130   for (i = 0; i < len; i++) {
 131     SwfdecAsValue tmp;
 132     type = swfdec_bits_get_u8 (bits);
 133     if (type >= SWFDEC_AMF_N_TYPES ||
 134         (func = parse_funcs[type]) == NULL) {
 135       SWFDEC_ERROR ("no parse func for AMF type %u", type);
 136       goto fail;
 137     }
 138     if (!func (context, bits, &tmp))
 139       goto fail;
 140     swfdec_as_array_push (SWFDEC_AS_ARRAY (array), &tmp);
 141   }
 142
 143   SWFDEC_AS_VALUE_SET_OBJECT (val, array);
 144   return TRUE;
 145
 146 fail:
 147   return FALSE;
 148 }
 149
 150 // FIXME: untested
 151 static gboolean
 152 swfdec_amf_parse_date (SwfdecAsContext *context, SwfdecBits *bits, SwfdecAsValue *val)
 153 {
 154   double milliseconds = swfdec_bits_get_bdouble (bits);
 155   int utc_offset = swfdec_bits_get_bu16 (bits);
 156
 157   if (utc_offset > 12 * 60)
 158     utc_offset -= 12 * 60;
 159
 160   SWFDEC_AS_VALUE_SET_OBJECT (val,
 161       swfdec_as_date_new (context, milliseconds, utc_offset));
 162   return TRUE;
 163 }
 164
 165 const SwfdecAmfParseFunc parse_funcs[SWFDEC_AMF_N_TYPES] = {
 166   [SWFDEC_AMF_NUMBER] = swfdec_amf_parse_number,
 167   [SWFDEC_AMF_BOOLEAN] = swfdec_amf_parse_boolean,
 168   [SWFDEC_AMF_STRING] = swfdec_amf_parse_string,
 169   [SWFDEC_AMF_OBJECT] = swfdec_amf_parse_object,
 170   [SWFDEC_AMF_MIXED_ARRAY] = swfdec_amf_parse_mixed_array,
 171   [SWFDEC_AMF_ARRAY] = swfdec_amf_parse_array,
 172   [SWFDEC_AMF_DATE] = swfdec_amf_parse_date,
 173 #if 0
 174   SWFDEC_AMF_MOVIECLIP = 4,
 175   SWFDEC_AMF_NULL = 5,
 176   SWFDEC_AMF_UNDEFINED = 6,
 177   SWFDEC_AMF_REFERENCE = 7,
 178   SWFDEC_AMF_END_OBJECT = 9,
 179   SWFDEC_AMF_BIG_STRING = 12,
 180   SWFDEC_AMF_RECORDSET = 14,
 181   SWFDEC_AMF_XML = 15,
 182   SWFDEC_AMF_CLASS = 16,
 183   SWFDEC_AMF_FLASH9 = 17,
 184 #endif
 185 };
 186
 187 gboolean
 188 swfdec_amf_parse_one (SwfdecAsContext *context, SwfdecBits *bits,
 189     SwfdecAmfType expected_type, SwfdecAsValue *rval)
 190 {
 191   SwfdecAmfParseFunc func;
 192   guint type;
 193
 194   g_return_val_if_fail (SWFDEC_IS_AS_CONTEXT (context), 0);
 195   g_return_val_if_fail (context->global != NULL, 0);
 196   g_return_val_if_fail (bits != NULL, FALSE);
 197   g_return_val_if_fail (rval != NULL, FALSE);
 198   g_return_val_if_fail (expected_type < SWFDEC_AMF_N_TYPES, FALSE);
 199
 200   type = swfdec_bits_get_u8 (bits);
 201   if (type != expected_type) {
 202     SWFDEC_ERROR ("parse object should be type %u, but is %u",
 203         expected_type, type);
 204     return FALSE;
 205   }
 206   if (type >= SWFDEC_AMF_N_TYPES ||
 207       (func = parse_funcs[type]) == NULL) {
 208     SWFDEC_ERROR ("no parse func for AMF type %u", type);
 209     return FALSE;
 210   }
 211   return func (context, bits, rval);
 212 }
 213
 214 guint
 215 swfdec_amf_parse (SwfdecAsContext *context, SwfdecBits *bits, guint n_items, ...)
 216 {
 217   va_list args;
 218   guint i;
 219
 220   g_return_val_if_fail (SWFDEC_IS_AS_CONTEXT (context), 0);
 221   g_return_val_if_fail (context->global != NULL, 0);
 222   g_return_val_if_fail (bits != NULL, 0);
 223
 224   va_start (args, n_items);
 225   for (i = 0; i < n_items; i++) {
 226     SwfdecAmfType type = va_arg (args, SwfdecAmfType);
 227     SwfdecAsValue *val = va_arg (args, SwfdecAsValue *);
 228     if (!swfdec_amf_parse_one (context, bits, type, val))
 229       break;
 230   }
 231   va_end (args);
 232   return i;
 233 }
 234