From: Kevin Day <thekevinday@gmail.com>
Date: Fri, 9 Jul 2021 01:27:10 +0000 (-0500)
Subject: Update: Add cygwin rough documentation.
X-Git-Tag: 0.5.4^0
X-Git-Url: https://git.kevux.org/?a=commitdiff_plain;h=1e170730a75586318d8944f1f5a990f88b57a8ea;p=fll

Update: Add cygwin rough documentation.

I had access to a Windows box and was curious to see if I could compile my project on Windows.
To my surprise, with Cygwin and only a minor set of changes, the byte_dump program compiled and worked flawlessly.
---

diff --git a/documents/cygwin.txt b/documents/cygwin.txt
new file mode 100644
index 0000000..8439b66
--- /dev/null
+++ b/documents/cygwin.txt
@@ -0,0 +1,31 @@
+The following are a collection of informal notes on getting this to compile and run under Windows using Cygwin.
+I may formalize this at a later point in time.
+
+I have tested and was able to successfully (statically) compile and run FLL+Byte Dump under Cygwin.
+The resulting binary could be transfered to another machine and runs if the cygwin.dll is copied with it (placed along the byte_dump.exe).
+
+To compile the FLL, some functionality needs to be disabled.
+Fortunately, FLL is specifically designed to be hackable so the process is easier that it might otherwise be.
+
+For a monolithic build, compiled statically, add the following to "defines_all" in the "data/build/settings" file.
+  "-D_di_libcap_ -D_pthread_attr_unsupported_ -D_pthread_sigqueue_unsupported_ -D_di_f_attribute_visibility_ -Df_attribute_visibility_hidden -Df_attribute_visibility_internal -Df_attribute_visibility_protected -Df_attribute_visibility_public"
+
+The file level_1/fl_control_group/c/control_group.c (for function fl_control_group_apply()) had to have the following changed from:
+      if (unshare(CLONE_NEWCGROUP) < 0) {
+        if (errno == EINVAL) return F_status_set_error(F_parameter);
+        if (errno == ENOMEM) return F_status_set_error(F_memory_not);
+        if (errno == ENOSPC) return F_status_set_error(F_space_not);
+        if (errno == EPERM) return F_status_set_error(F_prohibited);
+
+        return F_status_set_error(F_failure);
+      }
+to:
+      return F_status_set_error(F_supported_not);
+
+There may have been other things to disable that I forgot to document.
+
+I do not believe I had to make any changes to compile byte_dump.
+
+Compiling byte_dump statically against the FLL library is a bit inefficient in that it contains the entire FLL library.
+The byte_dump program only needs a portion of it.
+I may need to provide a list of everything that can be disabled to provide a smaller and more optimal byte_dump binary.