fix standard compliance issues

3 files changed, 10 insertions, 2 deletions

diff --git a/meson.build b/meson.build
index db0abc7..277e822 100644
--- a/meson.build
+++ b/meson.build
@@ -1,5 +1,7 @@
 project('animtool', 'c', default_options: ['warning_level=2', 'c_std=c23'])
 
+add_project_arguments(['-D_XOPEN_SOURCE=800', '-D_POSIX_C_SOURCE=202405L'], language: 'c')
+
 cc = meson.get_compiler('c')
 
 opengl = dependency('opengl')
diff --git a/src/fmt/nut.c b/src/fmt/nut.c
index 99f9a69..f9ca9fd 100644
--- a/src/fmt/nut.c
+++ b/src/fmt/nut.c
@@ -1,3 +1,4 @@
+#define _DEFAULT_SOURCE // can be removed once glibc knows about <endian.h> in POSIX 2024
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdbit.h>
diff --git a/src/render.c b/src/render.c
index 9c7d796..fd88278 100644
--- a/src/render.c
+++ b/src/render.c
@@ -146,8 +146,13 @@ static void render_seq(size_t n_inst, struct seq_inst inst[n_inst], struct scene
                             (ts_now.tv_nsec - state->start_ts.tv_nsec) / 1000000000.0 + 
                             (ts_now.tv_sec - state->start_ts.tv_sec);
                         double ahead = time - e_time - scene->live.data;
-                        if (ahead > 0.0)
-                            usleep(ahead * 1000000.0);
+                        if (ahead > 0.0) {
+                            uint64_t nanos = ahead * 1000000000.0;
+                            struct timespec ts_sleep;
+                            ts_sleep.tv_nsec = nanos % 1000000000;
+                            ts_sleep.tv_sec = nanos / 1000000000;
+                            nanosleep(&ts_sleep, nullptr);
+                        }
                     }
                 
                     struct draw_frame frame;