From 2df8008d22b58f87fe665de0fa8c5bbeb4b4a3d8 Mon Sep 17 00:00:00 2001

From: Michal Domonkos <mdomonko@redhat.com>

Date: Wed, 17 May 2023 12:39:47 +0200

Subject: [PATCH] Enable large file support on 32-bit systems again

Replace 32-bit sizes in types like off_t with 64-bits when building on

32-bit architectures, to enable large file support there.

This fixes a nasty regression introduced in the cmake transition.  As

autotools would set this flag to 64 automatically for us, applications

linking against librpm (such as libdnf, librepo, libsolv or drpm) are

already adapted to that and are also building with the value of 64

(explicitly, we never exported this flag through pkg-config ourselves).

However, us suddenly expecting 32-bits in those types on 32-bit systems

can blow up badly e.g. in functions that take an off_t parameter, like

Fseek().

There perhaps aren't that many low-level users of librpm but drpm is one

such example where exactly this happens when built against our current

master.  It calls headerRead(), leading to Fseek() which receives a

64-bit offset parameter where it expects a 32-bit one, thus silently

overwriting the following parameter from 1 to 0 (SEEK_CUR to SEEK_SET)

which messes up the whole reading sequence in drpm's rpm_read(),

producing a failure in drpm's test suite that doesn't make any sense at

first sight.

While at it, also export the flag through pkg-config so that anyone

linking against librpm is now guaranteed to work correctly even if they

don't set the flag themselves (kudos to Petr Pisar for suggesting this).

---

 CMakeLists.txt | 1 +

 rpm.pc.in      | 2 +-

 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt

index b006ed34e..dc28fd547 100644

--- a/CMakeLists.txt

+++ b/CMakeLists.txt

@@ -52,6 +52,7 @@ set(CMAKE_SHARED_MODULE_PREFIX "")

 set(CMAKE_POSITION_INDEPENDENT_CODE ON)

 include(GNUInstallDirs)

 add_compile_definitions(_GNU_SOURCE)

+add_definitions(-D_FILE_OFFSET_BITS=64)

 function(makemacros)

 	set(prefix ${CMAKE_INSTALL_PREFIX})

diff --git a/rpm.pc.in b/rpm.pc.in

index 46d42e7a3..791303e17 100644

--- a/rpm.pc.in

+++ b/rpm.pc.in

@@ -11,6 +11,6 @@ URL: @CMAKE_PROJECT_HOMEPAGE_URL@

 Requires: popt

 Requires.private: @ZSTD_REQUIRES@

 # Conflicts:

-Cflags: -I${includedir}

+Cflags: -I${includedir} -D_FILE_OFFSET_BITS=64

 Libs: -L${libdir} -lrpm -lrpmio

 Libs.private: -lpopt -lrt -lpthread @WITH_LZMA_LIB@ @WITH_BZ2_LIB@ @WITH_ZLIB_LIB@ @LUA_LIBS@

-- 

2.40.1