On 08/05/2021 21:03, Christian Franke wrote:
This experimental patch allows to reduce the footprint of a Cygwin
installation on Windows 10.
Thanks.
The I/O-control itself is in a new file compactos.cc because
WIN32_LEAN_AND_MEAN (win32.h) must not be used and some required
Yeah, I think "Any include of <windows.h> should be through this file"
is more a guideline than a rule, since we already break it in other
places :)
definitions are still missing in the current headers.
Let me encourage you to submit those to MinGW-w64 so they end up in the
w32api package.
Test results with 64bit Cygwin (Disk space used without / with
--compact-os):
Base installation: 135MiB / 66,1 MiB (-51%)
Installation with g++, Mingw, Perl, Python, Tex, ...: 2.19GiB / 854MiB
(-62%)
Base installation with NTFS compression: 78.7MiB (results in significant
file fragmentation, Compact OS does not)
Nice.
A few minor comments.
Date: Sat, 8 May 2021 21:25:07 +0200
Subject: [PATCH] Add new option '--compact-os'.
[...]> --- /dev/null
+++ b/compactos.cc
@@ -0,0 +1,62 @@
+//
+// compactos.cc
+//
+// Copyright (C) 2021 Christian Franke
+//
+// SPDX-License-Identifier: MIT
+//
+
+#include "compactos.h"
+
+#ifndef FSCTL_SET_EXTERNAL_BACKING
There should be a comment here saying "not yet provided by w32api" or
similar.
diff --git a/compactos.h b/compactos.h
new file mode 100644
index 0000000..c1470f1
--- /dev/null
+++ b/compactos.h
@@ -0,0 +1,26 @@
+//
+// compactos.h
+//
+// Copyright (C) 2021 Christian Franke
+//
+// SPDX-License-Identifier: MIT
+//
+
+#ifndef COMPACTOS_H
+#define COMPACTOS_H
+
+#ifndef _INC_WINDOWS
I hope windows.h already has it's own include guard?
+#include <windows.h>
+#endif
[...]
+bool io_stream_cygfile::compact_os_is_available = (OSMajorVersion () >= 10);
The documentation seems a bit vague, but are we really expecting this to
work on Windows 10 1507?
+
// Normalise a unix style path relative to
// cwd.
std::string
@@ -120,7 +125,22 @@ get_root_dir_now ()
read_mounts (std::string ());
}
-io_stream_cygfile::io_stream_cygfile (const std::string& name, const std::string& mode, mode_t perms) : fp(), lasterr (0), fname(), wname (NULL)
+static bool
+compactos_is_useless (const std::string& name)
Something like 'compression_useful' might be a bit clearer?
+{
+ const char * const p = name.c_str();
+ if (!(!strncmp (p, "/bin/", 5) || !strncmp (p, "/sbin/", 6) || !strncmp (p,
"/usr/", 5)))
+ return true; /* File is not in R/O tree. */
+ const size_t len = name.size(); /* >= 5 */
+ if (!strcmp (p + (len - 4), ".dll") || !strcmp (p + (len - 3), ".so"))
+ return true; /* Rebase will open file for writing which uncompresses the
file. */
+ if (!strcmp (p + (len - 3), ".gz") || !strcmp (p + (len - 3), ".xz"))
+ return true; /* File is already compressed. */
Is this an assertion that there are no .bz2, .lzma, .zst etc. files in
the install?
