b2 cannot deal with Windows archive files that exceed 2 GB

[pkl97]

The Windows archive scanner of b2 (inherited from Perforce Jam) is not able to handle Windows .lib files that exceed 2 GB in size.

We found this issue years ago in Perforce Jam and looking at the code of b2 it has the exact same issue.

This simple patch (changing 2 lines) fixes the problem:

diff --git a/src/engine/filent.cpp b/src/engine/filent.cpp
index 59a0f0d3b..4bab14b37 100644
--- a/src/engine/filent.cpp
+++ b/src/engine/filent.cpp
@@ -404,7 +404,7 @@ int file_collect_archive_content_( file_archive_info_t * const archive )
     struct ar_hdr ar_hdr;
     char * string_table = 0;
     char buf[ MAXJPATH ];
-    long offset;
+    __int64 offset;
     const char * path = object_str( archive->file->name );
     int const fd = open( path , O_RDONLY | O_BINARY, 0 );

@@ -503,7 +503,7 @@ int file_collect_archive_content_( file_archive_info_t * const archive )
         }

         offset += SARHDR + lar_size;
-        lseek( fd, offset, 0 );
+        _lseeki64( fd, offset, 0 );
     }

     close( fd );