Define _POSIX_C_SOURCE globally

Stop trying to maintain a per-file _POSIX_C_SOURCE. Instead,
require POSIX.1-2008 globally. A lot of core source files depend
on that already.

Some care must be taken on a few select files where we need a bit
more than POSIX. Some files need XSI extensions (_XOPEN_SOURCE) and
some files need BSD extensions (_DEFAULT_SOURCE). In both cases,
these feature test macros imply _POSIX_C_SOURCE. Make sure to not
define both these macros and _POSIX_C_SOURCE explicitly to avoid
POSIX requirement conflicts (e.g. _POSIX_C_SOURCE says POSIX.1-2001
but _XOPEN_SOURCE says POSIX.1-2008).

Additionally, there is one special case in render/vulkan/vulkan.c.
That file needs major()/minor(), and these are system-specific.
On FreeBSD, _POSIX_C_SOURCE hides system-specific symbols so we need
to make sure it's not defined for this file. On Linux, we can
explicitly include <sys/sysmacros.h> and ensure that apart from
symbols defined there the file only uses POSIX toys.

13 files changed, 2 insertions, 14 deletions

diff --git a/render/allocator/allocator.c b/render/allocator/allocator.c
index e0620a1b..639b52be 100644
--- a/render/allocator/allocator.c
+++ b/render/allocator/allocator.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <assert.h>
 #include <fcntl.h>
 #include <stdlib.h>
diff --git a/render/allocator/drm_dumb.c b/render/allocator/drm_dumb.c
index 6de44f40..eb4ce99f 100644
--- a/render/allocator/drm_dumb.c
+++ b/render/allocator/drm_dumb.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 
 #include <assert.h>
 #include <drm_fourcc.h>
diff --git a/render/allocator/gbm.c b/render/allocator/gbm.c
index 25ddbbae..baa0fb6e 100644
--- a/render/allocator/gbm.c
+++ b/render/allocator/gbm.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <assert.h>
 #include <drm_fourcc.h>
 #include <fcntl.h>
diff --git a/render/dmabuf.c b/render/dmabuf.c
index b0b8ef41..7096dbc0 100644
--- a/render/dmabuf.c
+++ b/render/dmabuf.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <fcntl.h>
 #include <unistd.h>
 #include <wlr/render/dmabuf.h>
diff --git a/render/egl.c b/render/egl.c
index 162634be..ac991295 100644
--- a/render/egl.c
+++ b/render/egl.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <assert.h>
 #include <drm_fourcc.h>
 #include <fcntl.h>
diff --git a/render/gles2/pass.c b/render/gles2/pass.c
index 4c9f9e28..9177b0a1 100644
--- a/render/gles2/pass.c
+++ b/render/gles2/pass.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 199309L
 #include <stdlib.h>
 #include <assert.h>
 #include <pixman.h>
diff --git a/render/gles2/pixel_format.c b/render/gles2/pixel_format.c
index fdf091f1..5cdf8c99 100644
--- a/render/gles2/pixel_format.c
+++ b/render/gles2/pixel_format.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 199309L
 #include <drm_fourcc.h>
 #include <GLES2/gl2.h>
 #include <GLES2/gl2ext.h>
diff --git a/render/gles2/renderer.c b/render/gles2/renderer.c
index a71423c0..e095f469 100644
--- a/render/gles2/renderer.c
+++ b/render/gles2/renderer.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 199309L
 #include <assert.h>
 #include <drm_fourcc.h>
 #include <GLES2/gl2.h>
diff --git a/render/gles2/texture.c b/render/gles2/texture.c
index d326da9d..d66e9c16 100644
--- a/render/gles2/texture.c
+++ b/render/gles2/texture.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 199309L
 #include <assert.h>
 #include <drm_fourcc.h>
 #include <GLES2/gl2.h>
diff --git a/render/vulkan/renderer.c b/render/vulkan/renderer.c
index 05486a0f..d433f495 100644
--- a/render/vulkan/renderer.c
+++ b/render/vulkan/renderer.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <assert.h>
 #include <fcntl.h>
 #include <math.h>
diff --git a/render/vulkan/texture.c b/render/vulkan/texture.c
index a3fede04..51372b5f 100644
--- a/render/vulkan/texture.c
+++ b/render/vulkan/texture.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <assert.h>
 #include <drm_fourcc.h>
 #include <fcntl.h>
diff --git a/render/vulkan/vulkan.c b/render/vulkan/vulkan.c
index 8e9d9288..54bfa77a 100644
--- a/render/vulkan/vulkan.c
+++ b/render/vulkan/vulkan.c
@@ -1,5 +1,5 @@
-#if !defined(__FreeBSD__)
-#define _POSIX_C_SOURCE 200809L
+#if defined(__FreeBSD__)
+#undef _POSIX_C_SOURCE
 #endif
 #include <assert.h>
 #include <fcntl.h>
diff --git a/render/wlr_renderer.c b/render/wlr_renderer.c
index 0ddb364e..513fecbd 100644
--- a/render/wlr_renderer.c
+++ b/render/wlr_renderer.c
@@ -1,4 +1,3 @@
-#define _POSIX_C_SOURCE 200809L
 #include <assert.h>
 #include <fcntl.h>
 #include <stdbool.h>