idmapped-mounts: Fix build error because of undefined reallocarray

On old glibc, reallocarray was not introduced, so this case compiles
failed.  We should use reallocarray if glibc supports and use
realloc if glibcs doesn't support reallocarray.

Signed-off-by: Yang Xu <xuyang2018.jy@fujitsu.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>

diff --git a/configure.ac b/configure.ac
index 0b55455a8daf3b6c7e42a706c291727a4854190d..6e5ab397301e3cd6a29bfcffe25e371942a91b3d 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -68,6 +68,7 @@ AC_PACKAGE_WANT_LIBBTRFSUTIL
 
 AC_HAVE_COPY_FILE_RANGE
 AC_CHECK_FUNCS([renameat2])
+AC_CHECK_FUNCS([reallocarray])
 AC_CHECK_TYPES([struct mount_attr], [], [], [[#include <linux/mount.h>]])
 AC_CHECK_TYPES([struct btrfs_qgroup_limit], [], [], [[
 #include <stddef.h>

diff --git a/src/idmapped-mounts/idmapped-mounts.c b/src/idmapped-mounts/idmapped-mounts.c
index 4230cb48c7bf6b081376bee8db13eff258c2ac2e..83b7c89ab01571ae8609c5605539d0992ab996e6 100644 (file)
--- a/src/idmapped-mounts/idmapped-mounts.c
+++ b/src/idmapped-mounts/idmapped-mounts.c
@@ -9910,8 +9910,12 @@ static int append_stack(struct btrfs_iter *iter, uint64_t tree_id, size_t path_l
        if (iter->stack_len >= iter->stack_capacity) {
                size_t new_capacity = iter->stack_capacity * 2;
                struct btrfs_stack *new_search_stack;
+#ifdef HAVE_REALLOCARRAY
                new_search_stack = reallocarray(iter->search_stack, new_capacity,
                                                sizeof(*iter->search_stack));
+#else
+               new_search_stack = realloc(iter->search_stack, new_capacity * sizeof(*iter->search_stack));
+#endif
                if (!new_search_stack)
                        return -ENOMEM;