id3lib  3.8.3
tag_render.cpp
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1 // $Id: tag_render.cpp,v 1.44 2002/07/31 13:20:49 t1mpy Exp $
2 
3 // id3lib: a C++ library for creating and manipulating id3v1/v2 tags
4 // Copyright 1999, 2000 Scott Thomas Haug
5 // Copyright 2002 Thijmen Klok (thijmen@id3lib.org)
6 
7 // This library is free software; you can redistribute it and/or modify it
8 // under the terms of the GNU Library General Public License as published by
9 // the Free Software Foundation; either version 2 of the License, or (at your
10 // option) any later version.
11 //
12 // This library is distributed in the hope that it will be useful, but WITHOUT
13 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
15 // License for more details.
16 //
17 // You should have received a copy of the GNU Library General Public License
18 // along with this library; if not, write to the Free Software Foundation,
19 // Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
20 
21 // The id3lib authors encourage improvements and optimisations to be sent to
22 // the id3lib coordinator. Please see the README file for details on where to
23 // send such submissions. See the AUTHORS file for a list of people who have
24 // contributed to id3lib. See the ChangeLog file for a list of changes to
25 // id3lib. These files are distributed with id3lib at
26 // http://download.sourceforge.net/id3lib/
27 
28 #include <memory.h>
29 #include "tag_impl.h" //has <stdio.h> "tag.h" "header_tag.h" "frame.h" "field.h" "spec.h" "id3lib_strings.h" "utils.h"
30 #include "helpers.h"
31 #include "writers.h"
32 #include "id3/io_decorators.h" //has "readers.h" "io_helpers.h" "utils.h"
33 #include "io_helpers.h"
34 #include "io_strings.h"
35 
36 #if defined HAVE_SYS_PARAM_H
37 #include <sys/param.h>
38 #endif
39 
40 using namespace dami;
41 
42 void id3::v1::render(ID3_Writer& writer, const ID3_TagImpl& tag)
43 {
44  writer.writeChars("TAG", 3);
45 
46  io::writeTrailingSpaces(writer, id3::v2::getTitle(tag), ID3_V1_LEN_TITLE);
47  io::writeTrailingSpaces(writer, id3::v2::getArtist(tag), ID3_V1_LEN_ARTIST);
48  io::writeTrailingSpaces(writer, id3::v2::getAlbum(tag), ID3_V1_LEN_ALBUM);
49  io::writeTrailingSpaces(writer, id3::v2::getYear(tag), ID3_V1_LEN_YEAR);
50 
51  size_t track = id3::v2::getTrackNum(tag);
52  String comment = id3::v2::getV1Comment(tag);
53  if (track > 0)
54  {
55  io::writeTrailingSpaces(writer, comment, ID3_V1_LEN_COMMENT - 2);
56  writer.writeChar('\0');
57  writer.writeChar((char) track);
58  }
59  else
60  {
61  io::writeTrailingSpaces(writer, comment, ID3_V1_LEN_COMMENT);
62  }
63  writer.writeChar((char) id3::v2::getGenreNum(tag));
64 }
65 
66 namespace
67 {
68  void renderFrames(ID3_Writer& writer, const ID3_TagImpl& tag)
69  {
70  for (ID3_TagImpl::const_iterator iter = tag.begin(); iter != tag.end(); ++iter)
71  {
72  const ID3_Frame* frame = *iter;
73  if (frame) frame->Render(writer);
74  }
75  }
76 }
77 
78 void id3::v2::render(ID3_Writer& writer, const ID3_TagImpl& tag)
79 {
80  // There has to be at least one frame for there to be a tag...
81  if (tag.NumFrames() == 0)
82  {
83  ID3D_WARNING( "id3::v2::render(): no frames to render" );
84  return;
85  }
86 
87  ID3D_NOTICE( "id3::v2::render(): rendering" );
88  ID3_TagHeader hdr;
89  hdr.SetSpec(tag.GetSpec());
90  hdr.SetExtended(tag.GetExtended());
92  hdr.SetFooter(tag.GetFooter());
93 
94  // set up the encryption and grouping IDs
95 
96  // ...
97  String frms;
98  io::StringWriter frmWriter(frms);
99  if (!tag.GetUnsync())
100  {
101  ID3D_NOTICE( "id3::v2::render(): rendering frames" );
102  renderFrames(frmWriter, tag);
103  hdr.SetUnsync(false);
104  }
105  else
106  {
107  ID3D_NOTICE( "id3::v2::render(): rendering unsynced frames" );
108  io::UnsyncedWriter uw(frmWriter);
109  renderFrames(uw, tag);
110  uw.flush();
111  ID3D_NOTICE( "id3::v2::render(): numsyncs = " << uw.getNumSyncs() );
112  hdr.SetUnsync(uw.getNumSyncs() > 0);
113  }
114  size_t frmSize = frms.size();
115  if (frmSize == 0)
116  {
117  ID3D_WARNING( "id3::v2::render(): rendered frame size is 0 bytes" );
118  return;
119  }
120 
121  // zero the remainder of the buffer so that our padding bytes are zero
122  luint nPadding = tag.PaddingSize(frmSize);
123  ID3D_NOTICE( "id3::v2::render(): padding size = " << nPadding );
124 
125  hdr.SetDataSize(frmSize + tag.GetExtendedBytes() + nPadding);
126 
127  hdr.Render(writer);
128 
129  writer.writeChars(frms.data(), frms.size());
130 
131  for (size_t i = 0; i < nPadding; ++i)
132  {
133  if (writer.writeChar('\0') == ID3_Writer::END_OF_WRITER)
134  {
135  break;
136  }
137  }
138 }
139 
140 size_t ID3_TagImpl::Size() const
141 {
142  if (this->NumFrames() == 0)
143  {
144  return 0;
145  }
146  ID3_TagHeader hdr;
147 
148  hdr.SetSpec(this->GetSpec());
149  size_t bytesUsed = hdr.Size();
150 
151  size_t frameBytes = 0;
152  for (const_iterator cur = _frames.begin(); cur != _frames.end(); ++cur)
153  {
154  if (*cur)
155  {
156  (*cur)->SetSpec(this->GetSpec());
157  frameBytes += (*cur)->Size();
158  }
159  }
160 
161  if (!frameBytes)
162  {
163  return 0;
164  }
165 
166  bytesUsed += frameBytes;
167  // add 30% for sync
168  if (this->GetUnsync())
169  {
170  bytesUsed += bytesUsed / 3;
171  }
172 
173  bytesUsed += this->PaddingSize(bytesUsed);
174  return bytesUsed;
175 }
176 
177 
179 {
180  if (this->GetSpec() == ID3V2_3_0)
181  {
182  }
183 
184  return ;
185 }
186 
187 
188 #define ID3_PADMULTIPLE (2048)
189 #define ID3_PADMAX (4096)
190 
191 
192 size_t ID3_TagImpl::PaddingSize(size_t curSize) const
193 {
194  luint newSize = 0;
195 
196  // if padding is switched off
197  if (! _is_padded)
198  {
199  return 0;
200  }
201 
202  // if the old tag was large enough to hold the new tag, then we will simply
203  // pad out the difference - that way the new tag can be written without
204  // shuffling the rest of the song file around
205  if ((this->GetPrependedBytes()-ID3_TagHeader::SIZE > 0) &&
206  (this->GetPrependedBytes()-ID3_TagHeader::SIZE >= curSize) &&
207  (this->GetPrependedBytes()-ID3_TagHeader::SIZE - curSize) < ID3_PADMAX)
208  {
209  newSize = this->GetPrependedBytes()-ID3_TagHeader::SIZE;
210  }
211  else
212  {
213  luint tempSize = curSize + ID3_GetDataSize(*this) +
214  this->GetAppendedBytes() + ID3_TagHeader::SIZE;
215 
216  // this method of automatic padding rounds the COMPLETE FILE up to the
217  // nearest 2K. If the file will already be an even multiple of 2K (with
218  // the tag included) then we just add another 2K of padding
219  tempSize = ((tempSize / ID3_PADMULTIPLE) + 1) * ID3_PADMULTIPLE;
220 
221  // the size of the new tag is the new filesize minus the audio data
222  newSize = tempSize - ID3_GetDataSize(*this) - this->GetAppendedBytes () -
224  }
225 
226  return newSize - curSize;
227 }
228 
The representative class of an id3v2 frame.
bool SetDataSize(size_t size)
Definition: header.h:64
bool SetExperimental(bool b)
Definition: header_tag.h:80
void Render(ID3_Writer &) const
Definition: header_tag.cpp:66
bool SetFooter(bool b)
Definition: header_tag.h:87
size_t Size() const
Definition: header_tag.cpp:53
bool SetSpec(ID3_V2Spec)
Definition: header_tag.cpp:39
bool SetExtended(bool b)
Definition: header_tag.h:73
bool SetUnsync(bool b)
Definition: header_tag.h:66
size_t GetExtendedBytes() const
Definition: tag_impl.cpp:278
size_t PaddingSize(size_t) const
Definition: tag_render.cpp:192
bool GetExperimental() const
Definition: tag_impl.cpp:268
size_t NumFrames() const
Definition: tag_impl.h:121
bool GetUnsync() const
Definition: tag_impl.cpp:258
bool GetExtended() const
Definition: tag_impl.cpp:263
iterator begin()
Definition: tag_impl.h:132
Frames::const_iterator const_iterator
Definition: tag_impl.h:78
void RenderExtHeader(uchar *)
Definition: tag_render.cpp:178
bool GetFooter() const
Definition: tag_impl.cpp:273
ID3_V2Spec GetSpec() const
Definition: tag_impl.cpp:232
size_t Size() const
Definition: tag_render.cpp:140
iterator end()
Definition: tag_impl.h:133
virtual size_type writeChars(const char_type buf[], size_type len)=0
Write up to len characters into buf and advance the internal position accordingly.
virtual int_type writeChar(char_type ch)
Write a single character and advance the internal position.
Definition: writer.h:71
static const int_type END_OF_WRITER
Definition: writer.h:41
long unsigned int luint
Definition: globals.h:115
@ ID3V2_3_0
Definition: globals.h:166
unsigned char uchar
Definition: globals.h:114
@ ID3_V1_LEN_YEAR
Definition: globals.h:336
@ ID3_V1_LEN_ARTIST
Definition: globals.h:334
@ ID3_V1_LEN_ALBUM
Definition: globals.h:335
@ ID3_V1_LEN_TITLE
Definition: globals.h:333
@ ID3_V1_LEN_COMMENT
Definition: globals.h:337
void render(ID3_Writer &, const ID3_TagImpl &)
Definition: tag_render.cpp:42
ID3_C_EXPORT String getArtist(const ID3_TagImpl &)
Definition: helpers.cpp:130
ID3_C_EXPORT size_t getGenreNum(const ID3_TagImpl &)
Definition: helpers.cpp:388
ID3_C_EXPORT String getTitle(const ID3_TagImpl &)
Definition: helpers.cpp:188
ID3_C_EXPORT String getAlbum(const ID3_TagImpl &)
Definition: helpers.cpp:165
ID3_C_EXPORT String getV1Comment(const ID3_TagImpl &)
Definition: helpers.cpp:243
void render(ID3_Writer &writer, const ID3_TagImpl &tag)
Definition: tag_render.cpp:78
ID3_C_EXPORT String getYear(const ID3_TagImpl &)
Definition: helpers.cpp:211
ID3_C_EXPORT size_t getTrackNum(const ID3_TagImpl &)
Definition: helpers.cpp:350
Definition: tag_impl.h:42
size_t ID3_GetDataSize(const ID3_TagImpl &tag)
Definition: tag_impl.cpp:323
#define ID3_PADMAX
Definition: tag_render.cpp:189
#define ID3_PADMULTIPLE
Definition: tag_render.cpp:188