+/*
+** Copyright (C) 2009-2011 Erik de Castro Lopo <erikd@mega-nerd.com>
+**
+** All rights reserved.
+**
+** Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**
+** * Redistributions of source code must retain the above copyright
+** notice, this list of conditions and the following disclaimer.
+** * Redistributions in binary form must reproduce the above copyright
+** notice, this list of conditions and the following disclaimer in
+** the documentation and/or other materials provided with the
+** distribution.
+** * Neither the author nor the names of any contributors may be used
+** to endorse or promote products derived from this software without
+** specific prior written permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+** TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+** PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+** EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+** OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+** OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+** ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sndfile.h>
+
+#include "common.h"
+
+#define BUFFER_LEN 4096
+#define MAX_INPUTS 16
+
+
+typedef struct
+{ SNDFILE * infile [MAX_INPUTS] ;
+ SNDFILE * outfile ;
+
+ union
+ { double d [BUFFER_LEN] ;
+ int i [BUFFER_LEN] ;
+ } din ;
+
+ union
+
+ { double d [MAX_INPUTS * BUFFER_LEN] ;
+ int i [MAX_INPUTS * BUFFER_LEN] ;
+ } dout ;
+
+ int channels ;
+} STATE ;
+
+
+static void usage_exit (void) ;
+static void interleave_int (STATE * state) ;
+static void interleave_double (STATE * state) ;
+
+
+int
+main (int argc, char **argv)
+{ STATE state ;
+ SF_INFO sfinfo ;
+ int k, double_merge = 0 ;
+
+ if (argc < 5)
+ { if (argc > 1)
+ puts ("\nError : need at least 2 input files.") ;
+ usage_exit () ;
+ } ;
+
+ if (strcmp (argv [argc - 2], "-o") != 0)
+ { puts ("\nError : second last command line parameter should be '-o'.\n") ;
+ usage_exit () ;
+ } ;
+
+ if (argc - 3 > MAX_INPUTS)
+ { printf ("\nError : Cannot handle more than %d input channels.\n\n", MAX_INPUTS) ;
+ exit (1) ;
+ } ;
+
+ memset (&state, 0, sizeof (state)) ;
+ memset (&sfinfo, 0, sizeof (sfinfo)) ;
+
+ for (k = 1 ; k < argc - 2 ; k++)
+ {
+ if ((state.infile [k - 1] = sf_open (argv [k], SFM_READ, &sfinfo)) == NULL)
+ { printf ("\nError : Not able to open input file '%s'\n%s\n", argv [k], sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ if (sfinfo.channels != 1)
+ { printf ("\bError : Input file '%s' should be mono (has %d channels).\n", argv [k], sfinfo.channels) ;
+ exit (1) ;
+ } ;
+
+ switch (sfinfo.format & SF_FORMAT_SUBMASK)
+ { case SF_FORMAT_FLOAT :
+ case SF_FORMAT_DOUBLE :
+ case SF_FORMAT_VORBIS :
+ double_merge = 1 ;
+ break ;
+
+ default :
+ break ;
+ } ;
+
+ state.channels ++ ;
+ } ;
+
+ sfinfo.channels = state.channels ;
+ sfinfo.format = sfe_file_type_of_ext (argv [argc - 1], sfinfo.format) ;
+
+ if ((state.outfile = sf_open (argv [argc - 1], SFM_WRITE, &sfinfo)) == NULL)
+ { printf ("Not able to open output file '%s'\n%s\n", argv [argc - 1], sf_strerror (NULL)) ;
+ exit (1) ;
+ } ;
+
+ if (double_merge)
+ interleave_double (&state) ;
+ else
+ interleave_int (&state) ;
+
+ for (k = 0 ; k < MAX_INPUTS ; k++)
+ if (state.infile [k] != NULL)
+ sf_close (state.infile [k]) ;
+ sf_close (state.outfile) ;
+
+ return 0 ;
+} /* main */
+
+/*------------------------------------------------------------------------------
+*/
+
+
+static void
+usage_exit (void)
+{ puts ("\nUsage : sndfile-interleave <input 1> <input 2> ... -o <output file>\n") ;
+ puts ("Merge two or more mono files into a single multi-channel file.\n") ;
+ printf ("Using %s.\n\n", sf_version_string ()) ;
+ exit (0) ;
+} /* usage_exit */
+
+
+static void
+interleave_int (STATE * state)
+{ int max_read_len, read_len ;
+ int ch, k ;
+
+ do
+ { max_read_len = 0 ;
+
+ for (ch = 0 ; ch < state->channels ; ch ++)
+ { read_len = sf_read_int (state->infile [ch], state->din.i, BUFFER_LEN) ;
+ if (read_len < BUFFER_LEN)
+ memset (state->din.i + read_len, 0, sizeof (state->din.i [0]) * (BUFFER_LEN - read_len)) ;
+
+ for (k = 0 ; k < read_len ; k++)
+ state->dout.i [k * state->channels + ch] = state->din.i [k] ;
+
+ max_read_len = MAX (max_read_len, read_len) ;
+ } ;
+
+ sf_writef_int (state->outfile, state->dout.i, max_read_len) ;
+ }
+ while (max_read_len > 0) ;
+
+} /* interleave_int */
+
+
+static void
+interleave_double (STATE * state)
+{ int max_read_len, read_len ;
+ int ch, k ;
+
+ do
+ { max_read_len = 0 ;
+
+ for (ch = 0 ; ch < state->channels ; ch ++)
+ { read_len = sf_read_double (state->infile [ch], state->din.d, BUFFER_LEN) ;
+ if (read_len < BUFFER_LEN)
+ memset (state->din.d + read_len, 0, sizeof (state->din.d [0]) * (BUFFER_LEN - read_len)) ;
+
+ for (k = 0 ; k < read_len ; k++)
+ state->dout.d [k * state->channels + ch] = state->din.d [k] ;
+
+ max_read_len = MAX (max_read_len, read_len) ;
+ } ;
+
+ sf_writef_double (state->outfile, state->dout.d, max_read_len) ;
+ }
+ while (max_read_len > 0) ;
+
+} /* interleave_double */