Merge mp3 detect/init code into mp3inputstream.cc/hh.

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

src/Makefile.am

 bin_PROGRAMS = audiowmark
 
-COMMON_SRC = utils.hh utils.cc convcode.hh convcode.cc random.hh random.cc mp3.cc mp3.hh wavdata.cc wavdata.hh \
+COMMON_SRC = utils.hh utils.cc convcode.hh convcode.cc random.hh random.cc wavdata.cc wavdata.hh \
 	     audiostream.cc audiostream.hh sfinputstream.cc sfinputstream.hh stdoutwavoutputstream.cc stdoutwavoutputstream.hh \
 	     sfoutputstream.cc sfoutputstream.hh rawinputstream.cc rawinputstream.hh rawoutputstream.cc rawoutputstream.hh \
 	     rawconverter.cc rawconverter.hh mp3inputstream.cc mp3inputstream.hh wmcommon.cc wmcommon.hh fft.cc fft.hh

src/audiostream.cc

@@ -24,7 +24,7 @@ AudioInputStream::create (const string& filename, Error& err)
       SFInputStream *sistream = new SFInputStream();
       in_stream.reset (sistream);
       err = sistream->open (filename);
-      if (err && mp3_detect (filename))
+      if (err && MP3InputStream::detect (filename))
         {
           MP3InputStream *mistream = new MP3InputStream();
           in_stream.reset (mistream);

src/mp3.cc

@@ -8,87 +8,4 @@
 using std::vector;
 using std::string;
 
-struct ScopedMHandle
-{
-  mpg123_handle *mh         = nullptr;
-  bool           need_close = false;
 
-  ~ScopedMHandle()
-  {
-    if (mh && need_close)
-      mpg123_close (mh);
-
-    if (mh)
-      mpg123_delete (mh);
-  }
-};
-
-void
-mp3_init()
-{
-  static bool mpg123_init_ok = false;
-  if (!mpg123_init_ok)
-    {
-      int err = mpg123_init();
-      if (err != MPG123_OK)
-        {
-          error ("audiowmark: init mpg123 lib failed\n");
-          exit (1);
-        }
-      mpg123_init_ok = true;
-    }
-}
-
-/* there is no really simple way of detecting if something is an mp3
- *
- * so we try to decode a few frames; if that works without error the
- * file is probably a valid mp3
- */
-bool
-mp3_detect (const string& filename)
-{
-  int err = 0;
-
-  mp3_init();
-
-  mpg123_handle *mh = mpg123_new (NULL, &err);
-  if (err != MPG123_OK)
-    return false;
-
-  auto smh = ScopedMHandle { mh }; // cleanup on return
-
-  err = mpg123_param (mh, MPG123_ADD_FLAGS, MPG123_QUIET, 0);
-  if (err != MPG123_OK)
-    return false;
-
-  err = mpg123_open (mh, filename.c_str());
-  if (err != MPG123_OK)
-    return false;
-
-  smh.need_close = true;
-
-  long rate;
-  int channels;
-  int encoding;
-  err = mpg123_getformat (mh, &rate, &channels, &encoding);
-  if (err != MPG123_OK)
-    return false;
-
-  size_t buffer_bytes = mpg123_outblock (mh);
-  unsigned char buffer[buffer_bytes];
-
-  for (size_t i = 0; i < 30; i++)
-    {
-      size_t done;
-      err = mpg123_read (mh, buffer, buffer_bytes, &done);
-      if (err == MPG123_DONE)
-        {
-          return true;
-        }
-      else if (err != MPG123_OK)
-        {
-          return false;
-        }
-    }
-  return true;
-}

src/mp3.hh

@@ -5,7 +5,5 @@
 
 #include "wavdata.hh"
 
-bool        mp3_detect (const std::string& filename);
-void        mp3_init();
 
 #endif /* AUDIOWMARK_MP3_HH */

src/mp3inputstream.cc

@@ -5,6 +5,23 @@
 #include <assert.h>
 
 using std::min;
+using std::string;
+
+static void
+mp3_init()
+{
+  static bool mpg123_init_ok = false;
+  if (!mpg123_init_ok)
+    {
+      int err = mpg123_init();
+      if (err != MPG123_OK)
+        {
+          error ("audiowmark: init mpg123 lib failed\n");
+          exit (1);
+        }
+      mpg123_init_ok = true;
+    }
+}
 
 MP3InputStream::~MP3InputStream()
 {
@@ -12,7 +29,7 @@ MP3InputStream::~MP3InputStream()
 }
 
 Error
-MP3InputStream::open (const std::string& filename)
+MP3InputStream::open (const string& filename)
 {
   int err = 0;
 
@@ -165,3 +182,72 @@ MP3InputStream::n_frames() const
 {
   return m_n_values / m_n_channels;
 }
+
+/* there is no really simple way of detecting if something is an mp3
+ *
+ * so we try to decode a few frames; if that works without error the
+ * file is probably a valid mp3
+ */
+bool
+MP3InputStream::detect (const string& filename)
+{
+  struct ScopedMHandle
+  {
+    mpg123_handle *mh         = nullptr;
+    bool           need_close = false;
+
+    ~ScopedMHandle()
+    {
+      if (mh && need_close)
+        mpg123_close (mh);
+
+      if (mh)
+        mpg123_delete (mh);
+    }
+  };
+
+  int err = 0;
+
+  mp3_init();
+
+  mpg123_handle *mh = mpg123_new (NULL, &err);
+  if (err != MPG123_OK)
+    return false;
+
+  auto smh = ScopedMHandle { mh }; // cleanup on return
+
+  err = mpg123_param (mh, MPG123_ADD_FLAGS, MPG123_QUIET, 0);
+  if (err != MPG123_OK)
+    return false;
+
+  err = mpg123_open (mh, filename.c_str());
+  if (err != MPG123_OK)
+    return false;
+
+  smh.need_close = true;
+
+  long rate;
+  int channels;
+  int encoding;
+  err = mpg123_getformat (mh, &rate, &channels, &encoding);
+  if (err != MPG123_OK)
+    return false;
+
+  size_t buffer_bytes = mpg123_outblock (mh);
+  unsigned char buffer[buffer_bytes];
+
+  for (size_t i = 0; i < 30; i++)
+    {
+      size_t done;
+      err = mpg123_read (mh, buffer, buffer_bytes, &done);
+      if (err == MPG123_DONE)
+        {
+          return true;
+        }
+      else if (err != MPG123_OK)
+        {
+          return false;
+        }
+    }
+  return true;
+}

src/mp3inputstream.hh

@@ -35,6 +35,7 @@ public:
   int     n_channels()  const override;
   size_t  n_frames() const override;
 
+  static bool detect (const std::string& filename);
 };
 
 #endif /* AUDIOWMARK_MP3_INPUT_STREAM_HH */

src/testmp3.cc

-#include "mp3.hh"
 #include "mp3inputstream.hh"
+#include "wavdata.hh"
 
 using std::string;
 
@@ -9,7 +9,7 @@ main (int argc, char **argv)
   WavData wd;
   if (argc >= 2)
     {
-      if (mp3_detect (argv[1]))
+      if (MP3InputStream::detect (argv[1]))
         {
           MP3InputStream m3i;
           Error err = m3i.open (argv[1]);