INTERSECTION not union

[backups/.git] / main.cpp

diff --git a/main.cpp b/main.cpp
index c7ae3876fbb13f84226cf415cc29825c862b21b7..fb7d522798909ef1d6c90533fed9fec48157adcc 100644 (file)
--- a/main.cpp
+++ b/main.cpp
@@ -12,38 +12,36 @@ using namespace std;
 static const unsigned int bytes_in_block = 0x800;
 static const char * dbname = "/var/lib/backups/backups.db";
 
-unsigned long long current_time() {
-  unsigned long long rc = 0;
-  time_t now_tt = time( 0 );
-  tm *now = localtime( &now_tt );
-  rc += ( now->tm_year + 1900ULL ) * 10000000000ULL;
-  rc += ( now->tm_mon  + 1ULL )    * 100000000ULL;
-  rc +=   now->tm_mday             * 1000000ULL;
-  rc +=   now->tm_hour             * 10000ULL;
-  rc +=   now->tm_min              * 100ULL;
-  rc +=   now->tm_sec;
-
-  return rc;
+unsigned long long read_time( istream &i ) {
+  string date_string;
+
+  int c;
+  // Todo, don't use char_traits<char> directly here
+  for( c = i.get(); 0 != c && char_traits<char>::eof() != c; c = i.get() ) {
+    date_string.push_back( c );
+  }
+  if( char_traits<char>::eof() == c ) { i.setstate( ios_base::eofbit ); }
+
+  return atoll( date_string.c_str() );
 }
 
 template<class I, class O, class INT>
 bool copy_until_full( I begin, I end, O out, INT &space ) {
   bool complete = true;
 
-  I i = begin;
-  while( 0 != space && i != end ) {
-    INT size = (*i)->getFileSize();
+  while( 0 != space && begin != end ) {
+    INT size = (*begin)->getFileSize();
     INT blocksize = blocks( size ) * bytes_in_block;
 
     if( blocksize <= space ) {
       space -= blocksize;
-      out = *i;
+      out = *begin;
       ++out;
     } else {
       // We missed a file that should be included so the backup is not complete
       complete = false;
     }
-    ++i;
+    ++begin;
   }
   return complete;
 }
@@ -66,25 +64,25 @@ void partition_sets( const SET &current, const SET &old,
                      SET &added, SET &common, SET &old_common, SET &deleted  ) {
   FileDataNameCmp cmp;
 
-  set_difference( current.begin(), current.end(),
-                  old.begin(),     old.end(),
-                  inserter( added, added.begin() ),
-                  cmp );
-
-  set_difference( old.begin(),     old.end(),
-                  current.begin(), current.end(),
-                  inserter( deleted, deleted.begin() ),
-                  cmp );
-
-  set_union(      current.begin(), current.end(),
-                  old.begin(),     old.end(),
-                  inserter( common, common.begin() ),
-                  cmp );
-
-  set_union(      old.begin(),    old.end(),
-                  common.begin(), common.end(),
-                  inserter( old_common, old_common.begin() ),
-                  cmp );
+  set_difference(   current.begin(), current.end(),
+                    old.begin(),     old.end(),
+                    inserter( added, added.begin() ),
+                    cmp );
+
+  set_difference(   old.begin(),     old.end(),
+                    current.begin(), current.end(),
+                    inserter( deleted, deleted.begin() ),
+                    cmp );
+
+  set_intersection( current.begin(), current.end(),
+                    old.begin(),     old.end(),
+                    inserter( common, common.begin() ),
+                    cmp );
+
+  set_intersection( old.begin(),    old.end(),
+                    common.begin(), common.end(),
+                    inserter( old_common, old_common.begin() ),
+                    cmp );
 }
 
 template<class INT>
@@ -105,7 +103,7 @@ void sizes( ITER begin, const ITER &end, INT &numblocks, INT &numbytes ) {
 
     numbytes  += filesize;
     numblocks += blocks( filesize );
-    begin++;
+    ++begin;
   }
 }
 
@@ -137,6 +135,9 @@ void delete_objects( ITER begin, const ITER &end ) {
 }
 
 int main() {
+  // Get the date on stdin
+  unsigned long long now = read_time( cin );
+
   // Parse the list of current files on stdin
   file_set current;
   populate_set( cin, current );
@@ -153,29 +154,28 @@ int main() {
 
   // Now find the list of files to backup.
   file_set backups;
-  insert_iterator<file_set> backups_i( backups, backups.begin() );
 
   // backup all added files
-  copy( added.begin(), added.end(), backups_i );
+  copy( added.begin(), added.end(), inserter( backups, backups.begin() ) );
 
   // Track the total size of added files
   unsigned long long added_blocks, added_bytes;
   sizes( added.begin(), added.end(), added_blocks, added_bytes );
 
-  file_vector modified_files;
+  file_vector modified_v;
   // Backup files that have been modified
   file_set::iterator i = common.begin(), j = old_common.begin();
   for( ; i != common.end(); ++i, ++j ) {
     (*i)->setLastBackupDate( (*j)->getLastBackupDate() );
 
-    if( needs_backup( *j, *i ) ) modified_files.push_back( *i );
+    if( needs_backup( *j, *i ) ) modified_v.push_back( *i );
   }
 
-  copy( modified_files.begin(), modified_files.end(), backups_i );
+  copy( modified_v.begin(), modified_v.end(), inserter( backups, backups.begin() ) );
 
   // Track the total size of modified files
   unsigned long long modified_blocks, modified_bytes;
-  sizes( modified_files.begin(), modified_files.end(), modified_blocks, modified_bytes );
+  sizes( modified_v.begin(), modified_v.end(), modified_blocks, modified_bytes );
 
   // Now, sort the backups by filesize and build a list that'll fit on a DVD
   file_vector backups_s;
@@ -185,7 +185,7 @@ int main() {
   sort( backups_s.begin(), backups_s.end(), sizecmp );
 
   file_set final;
-  unsigned long long space = 0x100000000ULL; // After looking at how big the ISO can be and how many 1K blocks are left after formatting the filesystem I decided on an even 4GB target
+  unsigned long long space = 0x100000000ULL;
 
   insert_iterator<file_set> final_i( final, final.begin() );
 
@@ -216,7 +216,6 @@ int main() {
   unsigned long long total_blocks, total_bytes;
   sizes( final.begin(), final.end(), total_blocks, total_bytes );
 
-  unsigned long long now = current_time();
   updateLastBackupDate( final.begin(), final.end(), now );
 
   // Write the 'current' list to the dbfile