[Buildroot] [git commit branch/2022.02.x] package/rsync: fix static build

[Peter Korsgaard]

commit: https://git.buildroot.net/buildroot/commit/?id=6289b788e3148ddef501311d8bfea8b314677054
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2022.02.x

Fix the following static build failure when using an external zlib:

/home/autobuild/autobuild/instance-11/output-1/host/bin/i686-buildroot-linux-uclibc-gcc -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64  -Og -g0  -static -DHAVE_CONFIG_H -Wall -W -Wno-unused-parameter -static -o rsync flist.o rsync.o generator.o receiver.o cleanup.o sender.o exclude.o util.o util2.o main.o checksum.o match.o syscall.o log.o backup.o delete.o options.o io.o compat.o hlink.o token.o uidlist.o socket.o hashtable.o usage.o fileio.o batch.o clientname.o chmod.o acls.o xattrs.o progress.o pipe.o   params.o loadparm.o clientserver.o access.o connection.o authenticate.o lib/wildmatch.o lib/compat.o lib/snprintf.o lib/mdfour.o lib/md5.o lib/permstring.o lib/pool_alloc.o lib/sysacls.o lib/sysxattrs.o    -lz -lpopt -liconv
/home/autobuild/autobuild/instance-11/output-1/host/lib/gcc/i686-buildroot-linux-uclibc/9.4.0/../../../../i686-buildroot-linux-uclibc/bin/ld: /home/autobuild/autobuild/instance-11/output-1/host/i686-buildroot-linux-uclibc/sysroot/usr/lib/libz.a(deflate.c.o): in function `read_buf':
deflate.c:(.text+0xb93): multiple definition of `read_buf'; io.o:io.c:(.text+0x2bf4): first defined here

Fixes:
 - http://autobuild.buildroot.org/results/488453197da880dda8f47b71ff302192bcbb6679

Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout at mind.be>
(cherry picked from commit bd1dfdf69a9939039c0a45ed97fb96a600752db7)
Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
---
 ...inking-with-a-zlib-with-external-read_buf.patch | 27 ++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/package/rsync/0002-Handle-linking-with-a-zlib-with-external-read_buf.patch b/package/rsync/0002-Handle-linking-with-a-zlib-with-external-read_buf.patch
new file mode 100644
index 0000000000..0af090732c
--- /dev/null
+++ b/package/rsync/0002-Handle-linking-with-a-zlib-with-external-read_buf.patch
@@ -0,0 +1,27 @@
+From 60dd42be603a79cd57cec076fe1680e9037be774 Mon Sep 17 00:00:00 2001
+From: Wayne Davison <wayne at opencoder.net>
+Date: Mon, 11 Apr 2022 08:29:54 -0700
+Subject: [PATCH] Handle linking with a zlib with external read_buf.
+
+[Retrieved from:
+https://github.com/WayneD/rsync/commit/60dd42be603a79cd57cec076fe1680e9037be774]
+Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
+---
+ rsync.h | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/rsync.h b/rsync.h
+index 4b30570b..e5aacd25 100644
+--- a/rsync.h
++++ b/rsync.h
+@@ -1172,6 +1172,10 @@ struct name_num_obj {
+ 	struct name_num_item list[10]; /* we'll get a compile error/warning if this is ever too small */
+ };
+ 
++#ifdef EXTERNAL_ZLIB
++#define read_buf read_buf_
++#endif
++
+ #ifndef __cplusplus
+ #include "proto.h"
+ #endif