Convert degenerate memcmp() to strncmp() in SQLite TimeMachine patch.

third_party/sqlite/mac_time_machine.patch

 Index: src/sqliteInt.h
 ===================================================================
 --- src/sqliteInt.h     (revision 87306)
 +++ src/sqliteInt.h     (working copy)
 @@ -2522,6 +2522,16 @@
  #endif
  
  /*
 +** The CoreServices.h and CoreFoundation.h headers are needed for excluding a
 +** -journal file from Time Machine backups when its associated database has
@@ skipping 37 matching lines @@
 @@ -5189,6 +5203,24 @@
    #else
          rc = sqlite3OsOpen(pVfs, pPager->zJournal, pPager->jfd, flags, 0);
    #endif
 +#if defined(__APPLE__)
 +        /* Set the TimeMachine exclusion metadata for the journal if it has
 +        ** been set for the database. Only do this for unix-type vfs
 +        ** implementations. */
 +        if( rc==SQLITE_OK && pPager->zFilename!=NULL
 +         && strlen(pPager->zFilename)>0
-+         && memcmp(pVfs->zName, "unix", 4)==0
++         && strncmp(pVfs->zName, "unix", 4)==0
 +         && ( pVfs->zName[4]=='-' || pVfs->zName[4]=='\0' ) ){
 +          CFURLRef database = create_cfurl_from_cstring(pPager->zFilename);
 +          if( CSBackupIsItemExcluded(database, NULL) ){
 +            CFURLRef journal = create_cfurl_from_cstring(pPager->zJournal);
 +            /* Ignore errors from the following exclusion call. */
 +            CSBackupSetItemExcluded(journal, TRUE, FALSE);
 +            CFRelease(journal);
 +          }
 +          CFRelease(database);
 +        }
@@ skipping 25 matching lines @@
  }
 @@ -162,7 +162,7 @@
    char x = *z;
    if( x==0 ) return 0;
    assert( x>='a' && x<='z' );
 -  j = cType[x-'a'];
 +  j = vOrCType[x-'a'];
    if( j<2 ) return 1-j;
    return isConsonant(z + 1);
  }