iOS does not support ucontext natively for aarch64 and the sigaltstack is
also unsupported (even worse, it fails silently, see:
https://openradar.appspot.com/13002712 )
As a workaround we include a library implementation of ucontext and add it
as a build option.
Signed-off-by: Joelle van Dyne <j...@getutm.app>
---
configure | 23 ++++++++++++++++++++---
meson.build | 11 ++++++++++-
util/coroutine-ucontext.c | 9 +++++++++
.gitmodules | 3 +++
meson_options.txt | 2 ++
subprojects/libucontext | 1 +
6 files changed, 45 insertions(+), 4 deletions(-)
create mode 160000 subprojects/libucontext
diff --git a/configure b/configure
index c1a08f0171..09dd22ebad 100755
--- a/configure
+++ b/configure
@@ -1767,7 +1767,7 @@ Advanced options (experts only):
--oss-lib path to OSS library
--cpu=CPU Build for host CPU [$cpu]
--with-coroutine=BACKEND coroutine backend. Supported options:
- ucontext, sigaltstack, windows
+ ucontext, libucontext, sigaltstack, windows
--enable-gcov enable test coverage analysis with gcov
--disable-blobs disable installing provided firmware blobs
--with-vss-sdk=SDK-path enable Windows VSS support in QEMU Guest Agent
@@ -4913,6 +4913,8 @@ if test "$coroutine" = ""; then
coroutine=win32
elif test "$ucontext_works" = "yes"; then
coroutine=ucontext
+ elif test "$ios" = "yes"; then
+ coroutine=libucontext
else
coroutine=sigaltstack
fi
@@ -4936,12 +4938,27 @@ else
error_exit "only the 'windows' coroutine backend is valid for Windows"
fi
;;
+ libucontext)
+ ;;
*)
error_exit "unknown coroutine backend $coroutine"
;;
esac
fi
+case $coroutine in
+libucontext)
+ git_submodules="${git_submodules} subprojects/libucontext"
+ mkdir -p libucontext
+ coroutine_impl=ucontext
+ libucontext="enabled"
+ ;;
+*)
+ coroutine_impl=$coroutine
+ libucontext="disabled"
+ ;;
+esac
+
if test "$coroutine_pool" = ""; then
coroutine_pool=yes
fi
@@ -6487,7 +6504,7 @@ if test "$rbd" = "yes" ; then
echo "RBD_LIBS=$rbd_libs" >> $config_host_mak
fi
-echo "CONFIG_COROUTINE_BACKEND=$coroutine" >> $config_host_mak
+echo "CONFIG_COROUTINE_BACKEND=$coroutine_impl" >> $config_host_mak
if test "$coroutine_pool" = "yes" ; then
echo "CONFIG_COROUTINE_POOL=1" >> $config_host_mak
else
@@ -7069,7 +7086,7 @@ NINJA=$ninja $meson setup \
-Dcocoa=$cocoa -Dmpath=$mpath -Dsdl=$sdl -Dsdl_image=$sdl_image \
-Dvnc=$vnc -Dvnc_sasl=$vnc_sasl -Dvnc_jpeg=$vnc_jpeg
-Dvnc_png=$vnc_png \
-Dgettext=$gettext -Dxkbcommon=$xkbcommon -Du2f=$u2f
-Dvirtiofsd=$virtiofsd \
- -Dcapstone=$capstone -Dslirp=$slirp -Dfdt=$fdt \
+ -Dcapstone=$capstone -Dslirp=$slirp -Dfdt=$fdt -Ducontext=$libucontext
\
-Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\
-Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \
-Dvhost_user_blk_server=$vhost_user_blk_server \
diff --git a/meson.build b/meson.build
index ee333b7a94..900dbc36c8 100644
--- a/meson.build
+++ b/meson.build
@@ -1308,9 +1308,17 @@ if not fdt.found() and fdt_required.length() > 0
error('fdt not available but required by targets ' + ', '.join(fdt_required))
endif
+ucontext = dependency('libucontext', required : false)
+if not ucontext.found() and get_option('ucontext').enabled()
+ libucontext_proj = subproject('libucontext',
+ default_options: ['freestanding=true'])
+ ucontext = libucontext_proj.get_variable('libucontext_dep')
+endif
+
config_host_data.set('CONFIG_CAPSTONE', capstone.found())
config_host_data.set('CONFIG_FDT', fdt.found())
config_host_data.set('CONFIG_SLIRP', slirp.found())
+config_host_data.set('CONFIG_LIBUCONTEXT', ucontext.found())
#####################
# Generated sources #
@@ -1528,7 +1536,7 @@ util_ss.add_all(trace_ss)
util_ss = util_ss.apply(config_all, strict: false)
libqemuutil = static_library('qemuutil',
sources: util_ss.sources() + stub_ss.sources() +
genh,
- dependencies: [util_ss.dependencies(), m, glib,
socket, malloc])
+ dependencies: [util_ss.dependencies(), m, glib,
socket, malloc, ucontext])
qemuutil = declare_dependency(link_with: libqemuutil,
sources: genh + version_res)
@@ -2188,6 +2196,7 @@ if targetos == 'windows'
summary_info += {'QGA MSI support': config_host.has_key('CONFIG_QGA_MSI')}
endif
summary_info += {'seccomp support': config_host.has_key('CONFIG_SECCOMP')}
+summary_info += {'libucontext support': ucontext.found()}
summary_info += {'coroutine backend': config_host['CONFIG_COROUTINE_BACKEND']}
summary_info += {'coroutine pool': config_host['CONFIG_COROUTINE_POOL'] ==
'1'}
summary_info += {'debug stack usage':
config_host.has_key('CONFIG_DEBUG_STACK_USAGE')}
diff --git a/util/coroutine-ucontext.c b/util/coroutine-ucontext.c
index 904b375192..220c57a743 100644
--- a/util/coroutine-ucontext.c
+++ b/util/coroutine-ucontext.c
@@ -23,7 +23,16 @@
#undef _FORTIFY_SOURCE
#endif
#include "qemu/osdep.h"
+#if defined(CONFIG_LIBUCONTEXT)
+#include <libucontext/libucontext.h>
+#define ucontext_t libucontext_ucontext_t
+#define getcontext libucontext_getcontext
+#define setcontext libucontext_setcontext
+#define swapcontext libucontext_swapcontext
+#define makecontext libucontext_makecontext
+#else
#include <ucontext.h>
+#endif
#include "qemu/coroutine_int.h"
#ifdef CONFIG_VALGRIND_H
diff --git a/.gitmodules b/.gitmodules
index 2bdeeacef8..4f02eed79a 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -64,3 +64,6 @@
[submodule "roms/vbootrom"]
path = roms/vbootrom
url = https://git.qemu.org/git/vbootrom.git
+[submodule "libucontext"]
+ path = subprojects/libucontext
+ url = https://github.com/utmapp/libucontext.git
diff --git a/meson_options.txt b/meson_options.txt
index 74ac853548..0a93bccea3 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -70,6 +70,8 @@ option('fuse', type: 'feature', value: 'auto',
description: 'FUSE block device export')
option('fuse_lseek', type : 'feature', value : 'auto',
description: 'SEEK_HOLE/SEEK_DATA support for FUSE exports')
+option('ucontext', type : 'feature', value : 'disabled',
+ description: 'libucontext support')
option('capstone', type: 'combo', value: 'auto',
choices: ['disabled', 'enabled', 'auto', 'system', 'internal'],
diff --git a/subprojects/libucontext b/subprojects/libucontext
new file mode 160000
index 0000000000..fc3b5e724e
--- /dev/null
+++ b/subprojects/libucontext
@@ -0,0 +1 @@
+Subproject commit fc3b5e724e21c2c01e2c93b344ab0e34b5a6649b
--
2.28.0
