[PATCH] unittests: fix syscall mocks on 32-bit with time64 glibc

[Bastian Germann]

On 32-bit systems (e.g. armhf), building with -D_FORTIFY_SOURCE=2,
-D_FILE_OFFSET_BITS=64, and -D_TIME_BITS=64 CFLAGS fails many tests.
These flags activate glibc symbol redirects that bypass the --wrap
linker interpositions used by the cmocka mocks:

  - _FORTIFY_SOURCE=2 + _FILE_OFFSET_BITS=64: open(path, flags) -> open64()
  - _FILE_OFFSET_BITS=64: lseek() -> lseek64()
  - _TIME_BITS=64 (glibc >= 2.34): ioctl() -> __ioctl_time64()

Add --wrap entries for each redirected symbol and provide thin forwarders
that delegate to the primary __wrap_open / __wrap_lseek / __wrap_ioctl
functions via plain function calls. This ensures that __func__ inside
those functions resolves correctly for cmocka's expectation lookup.

Signed-off-by: Bastian Germann <bage at debian.org>
---
 tests/unittests/Makemodule.am |  4 ++--
 tests/unittests/test_lib.h    | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/tests/unittests/Makemodule.am b/tests/unittests/Makemodule.am
index 277cac2..7b2ba4d 100644
--- a/tests/unittests/Makemodule.am
+++ b/tests/unittests/Makemodule.am
@@ -1,13 +1,13 @@
 ubilib_test_SOURCES = tests/unittests/libubi_test.c lib/libubi.c
 ubilib_test_SOURCES += tests/unittests/test_lib.h
 ubilib_test_LDADD = $(CMOCKA_LIBS)
-ubilib_test_LDFLAGS = -Wl,--wrap=open -Wl,--wrap=close -Wl,--wrap=ioctl -Wl,--wrap=read -Wl,--wrap=lseek
+ubilib_test_LDFLAGS = -Wl,--wrap=open -Wl,--wrap=open64 -Wl,--wrap=close -Wl,--wrap=ioctl -Wl,--wrap=__ioctl_time64 -Wl,--wrap=read -Wl,--wrap=lseek -Wl,--wrap=lseek64
 ubilib_test_CPPFLAGS = -O0 --std=gnu99 $(CMOCKA_CFLAGS) -I$(top_srcdir)/include -DSYSFS_ROOT='"$(top_srcdir)/tests/unittests/sysfs_mock"'
 
 mtdlib_test_SOURCES = tests/unittests/libmtd_test.c lib/libmtd.c lib/libmtd_legacy.c
 mtdlib_test_SOURCES += tests/unittests/test_lib.h
 mtdlib_test_LDADD = $(CMOCKA_LIBS)
-mtdlib_test_LDFLAGS = -Wl,--wrap=open -Wl,--wrap=close -Wl,--wrap=ioctl -Wl,--wrap=read -Wl,--wrap=lseek -Wl,--wrap=write
+mtdlib_test_LDFLAGS = -Wl,--wrap=open -Wl,--wrap=open64 -Wl,--wrap=close -Wl,--wrap=ioctl -Wl,--wrap=__ioctl_time64 -Wl,--wrap=read -Wl,--wrap=lseek -Wl,--wrap=lseek64 -Wl,--wrap=write
 mtdlib_test_CPPFLAGS = -O0 -D_GNU_SOURCE --std=gnu99 $(CMOCKA_CFLAGS) -I$(top_srcdir)/lib/ -I$(top_srcdir)/include -DSYSFS_ROOT='"$(top_srcdir)/tests/unittests/sysfs_mock"'
 
 TEST_BINS = \
diff --git a/tests/unittests/test_lib.h b/tests/unittests/test_lib.h
index cd94d9f..7a5b98b 100644
--- a/tests/unittests/test_lib.h
+++ b/tests/unittests/test_lib.h
@@ -89,6 +89,25 @@ off_t __wrap_lseek(int fd, off_t seek, int whence)
 	return mock_type(off_t);
 }
 
+int __wrap_open64(const char *path, int flags)
+{
+        return __wrap_open(path, flags);
+}
+
+off_t __wrap_lseek64(int fd, off_t offset, int whence)
+{
+        return __wrap_lseek(fd, offset, whence);
+}
+
+int __wrap___ioctl_time64(int fd, unsigned long req, ...)
+{
+        va_list ap;
+        va_start(ap, req);
+        void *arg = va_arg(ap, void *);
+        va_end(ap);
+        return __wrap_ioctl(fd, req, arg);
+}
+
 #define expect_open(X,Y,Z) do { \
 		expect_string(__wrap_open, path, X);\
 		will_return(__wrap_open, Y);\