2017-03-29 Fred Gleason <fredg@paravelsystems.com>

* Added a 'CUTS.SHA1_HASH' field to the database.
	* Incremented the database version to 261.
	* Added a 'Sha1' column to the Cut List in 'rdlibrary/audio_cart.cpp'.
	* Added 'RDCut::sha1Hash()' and 'RDCut::setSha1Hash()' methods in
	'lib/rdcut.cpp' and 'lib/rdcut.h'.
	* Added a '--rehash=' directive to rddbcheck(8).
	* Added a 'Rehash' Web API call.
	* Added an 'RDRehash' class in 'lib/rdrehash.cpp' and 'lib/rdrehash.h'.

lib/rdhash.cpp

@@ -0,0 +1,59 @@
+// rdhash.cpp
+//
+// Functions for generating hashes.
+//
+//   (C) Copyright 2017 Fred Gleason <fredg@paravelsystems.com>
+//
+//   This program is free software; you can redistribute it and/or modify
+//   it under the terms of the GNU General Public License version 2 as
+//   published by the Free Software Foundation.
+//
+//   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, write to the Free Software
+//   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+//
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <stdio.h>
+
+#include <openssl/sha.h>
+
+#include "rdhash.h"
+
+QString RDSha1Hash(const QString &filename,bool throttle)
+{
+  QString ret;
+  SHA_CTX ctx;
+  int fd=-1;
+  int n;
+  char data[1024];
+  unsigned char md[SHA_DIGEST_LENGTH];
+
+  if((fd=open(filename,O_RDONLY))<0) {
+    return ret;
+  }
+  SHA1_Init(&ctx);
+  while((n=read(fd,data,1024))>0) {
+    SHA1_Update(&ctx,data,n);
+    if(throttle) {
+      usleep(1);
+    }
+  }
+  close(fd);
+  SHA1_Final(md,&ctx);
+  ret="";
+  for(int i=0;i<SHA_DIGEST_LENGTH;i++) {
+    ret+=QString().sprintf("%02x",0xff&md[i]);
+  }
+
+  return ret;
+}