plugins: move qemu-plugin.h to include/plugins/

This change has two benefits:
- ensure plugins can't include anything else from QEMU than plugins API
- when compiling a C++ module, solves the header conflict with iostream
  header that includes transitively the wrong ctype.h, which already
  exists in include/qemu.

By Hyrum's law, there was already one usage of other headers with mem
plugin, which has been eliminated in previous commit.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Link: https://lore.kernel.org/qemu-devel/20260124182921.531562-7-pierrick.bouvier@linaro.org
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>

docs/devel/tcg-plugins.rst

@@ -166,7 +166,7 @@ Plugin API
 ==========
 
 The following API is generated from the inline documentation in
-``include/qemu/qemu-plugin.h``. Please ensure any updates to the API
+``include/plugins/qemu-plugin.h``. Please ensure any updates to the API
 include the full kernel-doc annotations.
 
-.. kernel-doc:: include/qemu/qemu-plugin.h
+.. kernel-doc:: include/plugins/qemu-plugin.h

include/plugins/qemu-plugin.h

@@ -2,9 +2,6 @@
  * Copyright (C) 2017, Emilio G. Cota <cota@braap.org>
  * Copyright (C) 2019, Linaro
  *
- * License: GNU GPL, version 2 or later.
- *   See the COPYING file in the top-level directory.
- *
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
 

include/qemu/plugin.h

@@ -8,7 +8,7 @@
 #define QEMU_PLUGIN_H
 
 #include "qemu/config-file.h"
-#include "qemu/qemu-plugin.h"
+#include "plugins/qemu-plugin.h"
 #include "qemu/error-report.h"
 #include "qemu/queue.h"
 #include "qemu/option.h"

meson.build

@@ -4446,7 +4446,7 @@ endforeach
 # Other build targets
 
 if get_option('plugins')
-  install_headers('include/qemu/qemu-plugin.h')
+  install_headers('include/plugins/qemu-plugin.h')
   if host_os == 'windows'
     # On windows, we want to deliver the qemu_plugin_api.lib file in the qemu installer,
     # so that plugin authors can compile against it.

plugins/core.c

@@ -15,7 +15,7 @@
 #include "qemu/lockable.h"
 #include "qemu/option.h"
 #include "qemu/plugin.h"
-#include "qemu/qemu-plugin.h"
+#include "plugins/qemu-plugin.h"
 #include "qemu/queue.h"
 #include "qemu/rcu_queue.h"
 #include "qemu/rcu.h"

plugins/meson.build

@@ -3,7 +3,7 @@ if not get_option('plugins')
 endif
 
 qemu_plugin_symbols = configure_file(
-  input: files('../include/qemu/qemu-plugin.h'),
+  input: files('../include/plugins/qemu-plugin.h'),
   output: 'qemu-plugin.symbols',
   capture: true,
   command: [files('../scripts/qemu-plugin-symbols.py'), '@INPUT@'])
@@ -62,12 +62,12 @@ endif
 
 if host_os == 'windows'
   plugins_deps = declare_dependency(sources: [files('win32_linker.c')],
-                                    include_directories: '../include/qemu',
+                                    include_directories: '../include/plugins',
                                     link_with: win32_qemu_plugin_api_lib,
                                     link_args: win32_qemu_plugin_api_link_flags,
                                     dependencies: glib)
 else
-  plugins_deps = declare_dependency(include_directories: '../include/qemu',
+  plugins_deps = declare_dependency(include_directories: '../include/plugins',
                                     dependencies: glib)
 endif