tree-wide: Mark linux and sys includes as system includes

Even though these are in our tree, we should still treat them as
system includes which helps various tools (clangd, iwyu, ...) understand
that these are system includes and <> should be used instead of "".

LICENSES/README.md

@@ -32,23 +32,23 @@ The following exceptions apply:
  * some sources under src/udev/ are licensed under **GPL-2.0-or-later**,
    so all udev programs (`systemd-udevd`, `udevadm`, and the udev builtins
    and test programs) are also distributed under **GPL-2.0-or-later**.
- * the header files contained in src/basic/linux/ are copied
+ * the header files contained in src/basic/include/linux are copied
    verbatim from the Linux kernel source tree and are licensed under **GPL-2.0 WITH
    Linux-syscall-note** and are used within the scope of the Linux-syscall-note
    exception provisions
  * the following sources are licensed under the **LGPL-2.0-or-later** license:
    - src/basic/utf8.c
    - src/shared/initreq.h
- * the src/basic/linux/bpf_insn.h header is copied from the Linux kernel
+ * the src/basic/include/linux/bpf_insn.h header is copied from the Linux kernel
    source tree and is licensed under either **BSD-2-Clause** or **GPL-2.0-only**,
    and thus is included in the systemd build under the BSD-2-Clause license.
- * The src/basic/linux/wireguard.h header is copied from the Linux kernel
+ * The src/basic/include/linux/wireguard.h header is copied from the Linux kernel
    source tree and is licensed under either **MIT** or **GPL-2.0 WITH Linux-syscall-note**,
    and thus is included in the systemd build under the MIT license.
  * the following sources are licensed under the **MIT** license (in case of our
    scripts, to facilitate copying and reuse of those helpers to other projects):
    - hwdb.d/parse_hwdb.py
-   - src/basic/linux/batman_adv.h
+   - src/basic/include/linux/batman_adv.h
    - src/basic/sparse-endian.h
    - tools/catalog-report.py
  * the following sources are licensed under the **CC0-1.0** license:

coccinelle/run-coccinelle.sh

@@ -5,7 +5,7 @@ set -e
 # Exclude following paths from the Coccinelle transformations
 EXCLUDED_PATHS=(
     "src/boot/efi/*"
-    "src/basic/linux/*"
+    "src/basic/include/linux/*"
     # Symlinked to test-bus-vtable-cc.cc, which causes issues with the IN_SET macro
     "src/libsystemd/sd-bus/test-bus-vtable.c"
     "src/libsystemd/sd-journal/lookup3.c"

meson.build

@@ -2053,11 +2053,18 @@ boot_stubs = []
 
 build_dir_include = include_directories('.')
 
-basic_includes = include_directories(
-        'src/basic',
-        'src/fundamental',
-        'src/systemd',
-        '.')
+basic_includes = [
+        include_directories(
+                'src/basic',
+                'src/fundamental',
+                'src/systemd',
+                '.',
+        ),
+        include_directories(
+                'src/basic/include',
+                is_system : true,
+        ),
+]
 
 libsystemd_includes = [basic_includes, include_directories(
         'src/libsystemd/sd-bus',

src/basic/meson.build

@@ -133,14 +133,14 @@ generate_arphrd_list = find_program('generate-arphrd-list.sh')
 arphrd_list_txt = custom_target(
         'arphrd-list.txt',
         output : 'arphrd-list.txt',
-        command : [generate_arphrd_list, cpp, files('linux/if_arp.h'), config_h],
+        command : [generate_arphrd_list, cpp, files('include/linux/if_arp.h'), config_h],
         capture : true)
 
 generate_cap_list = find_program('generate-cap-list.sh')
 cap_list_txt = custom_target(
         'cap-list.txt',
         output : 'cap-list.txt',
-        command : [generate_cap_list, cpp, files('linux/capability.h')],
+        command : [generate_cap_list, cpp, files('include/linux/capability.h')],
         capture : true)
 
 generate_errno_list = find_program('generate-errno-list.sh')
@@ -238,7 +238,7 @@ run_target(
 ############################################################
 
 filesystem_includes = files(
-        'linux/magic.h',
+        'include/linux/magic.h',
         'missing_magic.h',
 )
 

src/shared/meson.build

@@ -307,7 +307,7 @@ shared_sources += shared_generated_gperf_headers
 fname = 'ethtool-link-mode.h'
 ethtool_link_mode_h = custom_target(
         fname,
-        input : ['ethtool-link-mode.py', '../basic/linux/ethtool.h'],
+        input : ['ethtool-link-mode.py', '../basic/include/linux/ethtool.h'],
         output : fname,
         command : [python, '@INPUT0@', '--header', cpp, '@INPUT1@'],
         capture : true)
@@ -316,7 +316,7 @@ shared_sources += ethtool_link_mode_h
 fname = 'ethtool-link-mode.xml'
 ethtool_link_mode_xml = custom_target(
         fname,
-        input : ['ethtool-link-mode.py', '../basic/linux/ethtool.h'],
+        input : ['ethtool-link-mode.py', '../basic/include/linux/ethtool.h'],
         output : fname,
         command : [python, '@INPUT0@', '--xml', cpp, '@INPUT1@'],
         capture : true)

src/udev/meson.build

@@ -65,7 +65,7 @@ endif
 generate_keyboard_keys_list = find_program('generate-keyboard-keys-list.sh')
 keyboard_keys_list_txt = custom_target(
         'keyboard-keys-list.txt',
-        input : files('../basic/linux/input.h'),
+        input : files('../basic/include/linux/input.h'),
         output : 'keyboard-keys-list.txt',
         command : [generate_keyboard_keys_list, cpp, '@INPUT@'],
         capture : true)