Started to implement code to embed custom data in .ts files.

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/Makefile.am

@@ -11,7 +11,7 @@ COMMON_LIBS = $(SNDFILE_LIBS) $(FFTW_LIBS) $(LIBGCRYPT_LIBS) $(LIBMPG123_LIBS)
 audiowmark_SOURCES = audiowmark.cc wmget.cc wmadd.cc $(COMMON_SRC)
 audiowmark_LDFLAGS = $(COMMON_LIBS)
 
-noinst_PROGRAMS = testconvcode testrandom testmp3 teststream testlimiter
+noinst_PROGRAMS = testconvcode testrandom testmp3 teststream testlimiter testmpegts
 
 testconvcode_SOURCES = testconvcode.cc $(COMMON_SRC)
 testconvcode_LDFLAGS = $(COMMON_LIBS)
@@ -27,3 +27,6 @@ teststream_LDFLAGS = $(COMMON_LIBS)
 
 testlimiter_SOURCES = testlimiter.cc $(COMMON_SRC)
 testlimiter_LDFLAGS = $(COMMON_LIBS)
+
+testmpegts_SOURCES = testmpegts.cc $(COMMON_SRC)
+testmpegts_LDFLAGS = $(COMMON_LIBS)

src/testmpegts.cc

+/*
+ * Copyright (C) 2018-2020 Stefan Westerfeld
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <string.h>
+#include <stdio.h>
+
+#include <array>
+
+#include "utils.hh"
+
+using std::string;
+using std::vector;
+
+class TSPacket
+{
+  std::array<unsigned char, 188> data;
+
+public:
+  bool
+  read (FILE *file, Error& err)
+  {
+    err = Error::Code::NONE;
+
+    size_t bytes_read = fread (data.data(), 1, data.size(), file);
+    if (bytes_read == 0) /* probably eof */
+      return false;
+
+    if (bytes_read == data.size()) /* successful read */
+      {
+        if (data[0] == 'G')
+          return true;
+
+        err = Error ("bad packet sync while reading transport (.ts) packet");
+        return false;
+      }
+
+    err = Error ("short read while reading transport stream (.ts) packet");
+    return false;
+  }
+  Error
+  write (FILE *file)
+  {
+    size_t bytes_written = fwrite (data.data(), 1, data.size(), file);
+    if (bytes_written != data.size())
+      return Error ("short write while writing transport stream (.ts) packet");
+
+    return Error::Code::NONE;
+  }
+  enum Type { awmk_file, awmk_data };
+  void
+  clear (Type type)
+  {
+    std::fill (data.begin(), data.end(), 0);
+    auto id = get_id_bytes (type);
+    std::copy (id.begin(), id.end(), data.begin());
+  }
+  unsigned char&
+  operator[] (size_t n)
+  {
+    return data[n];
+  }
+  bool
+  has_id (Type type)
+  {
+    const auto idb = get_id_bytes (type);
+    for (size_t i = 0; i < idb.size(); i++)
+      {
+        if (idb[i] != data[i])
+          return false;
+      }
+    return true;
+  }
+  std::array<unsigned char, 12>
+  get_id_bytes (Type type)
+  {
+    if (type == awmk_file)
+     return { 'G', 0x1F, 0xFF, 0x10, 'A', 'W', 'M', 'K', 'f', 'i', 'l', 'e' };
+    if (type == awmk_data)
+      return { 'G', 0x1F, 0xFF, 0x10, 'A', 'W', 'M', 'K', 'd', 'a', 't', 'a' };
+    return {0,};
+  }
+  constexpr size_t
+  size()
+  {
+    return data.size(); // is constant
+  }
+};
+
+Error
+ts_append (const string& inname, const string& outname, const string& dataname)
+{
+  FILE *infile = fopen (inname.c_str(), "r");
+  FILE *outfile = fopen (outname.c_str(), "w");
+
+  while (!feof (infile))
+    {
+      TSPacket p;
+      Error err;
+      bool read_ok = p.read (infile, err);
+      if (!read_ok)
+        {
+          if (err)
+            return err;
+        }
+      else
+        {
+          err = p.write (outfile);
+        }
+    }
+  vector<unsigned char> data;
+  FILE *datafile = fopen (dataname.c_str(), "r");
+  int c;
+  while ((c = fgetc (datafile)) > 0)
+    data.push_back (c);
+
+  char buf[1024];
+  sprintf (buf, "%zd", data.size());
+  string header = buf;
+  header += ":" + dataname;
+  header += '\0';
+  for (size_t i = 0; i < header.size(); i++)
+    data.insert (data.begin() + i, header[i]);
+
+  TSPacket p_file;
+  p_file.clear (TSPacket::awmk_file);
+  size_t data_pos = 0;
+  int pos = 12;
+  while (data_pos < data.size())
+    {
+      p_file[pos++] = data[data_pos];
+      if (pos == 188)
+        {
+          p_file.write (outfile);
+          p_file.clear (TSPacket::awmk_data);
+          pos = 12;
+        }
+      data_pos++;
+    }
+
+  if (pos != 12)
+    {
+      Error err = p_file.write (outfile);
+    }
+
+  return Error::Code::NONE;
+}
+
+Error
+ts_list (const string& inname)
+{
+  FILE *infile = fopen (inname.c_str(), "r");
+
+  vector<unsigned char> awmk_stream;
+  while (!feof (infile))
+    {
+      TSPacket p;
+      Error err;
+      bool read_ok = p.read (infile, err);
+      if (!read_ok)
+        {
+          if (err)
+            return err;
+        }
+      else
+        {
+
+          if (p.has_id (TSPacket::awmk_file) || p.has_id (TSPacket::awmk_data))
+            {
+              for (size_t i = 12; i < p.size(); i++)
+                awmk_stream.push_back (p[i]);
+            }
+        }
+    }
+  int end = -1;
+  for (size_t i = 0; i < awmk_stream.size(); i++)
+    if (awmk_stream[i] == 0)
+      {
+        end = i + 1;
+        break;
+      }
+
+  if (end > 0)
+    {
+      int data_len = atoi ((char *) awmk_stream.data());
+      for (int i = end; i < end + data_len; i++)
+        printf ("%c", awmk_stream[i]);
+    }
+  return Error::Code::NONE;
+}
+
+int
+main (int argc, char **argv)
+{
+  if (argc == 5 && strcmp (argv[1], "append") == 0)
+    {
+      printf ("append: in=%s out=%s fn=%s\n", argv[2], argv[3], argv[4]);
+      Error err = ts_append (argv[2], argv[3], argv[4]);
+      if (err)
+        {
+          error ("ts_append: %s\n", err.message());
+          return 1;
+        }
+    }
+  if (argc == 3 && strcmp (argv[1], "list") == 0)
+    {
+      Error err = ts_list (argv[2]);
+    }
+}