rust: add utility procedural macro crate

This commit adds a helper crate library, qemu-api-macros for derive (and
other procedural) macros to be used along qemu-api.

It needs to be a separate library because in Rust, procedural macros, or
macros that can generate arbitrary code, need to be special separate
compilation units.

Only one macro is introduced in this patch, #[derive(Object)]. It
generates a constructor to register a QOM TypeInfo on init and it must
be used on types that implement qemu_api::definitions::ObjectImpl trait.

Reviewed-by: Junjie Mao <junjie.mao@hotmail.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Link: https://lore.kernel.org/r/dd645642406a6dc2060c6f3f17db2bc77ed67b59.1727961605.git.manos.pitsidianakis@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

subprojects/.gitignore

@@ -6,3 +6,7 @@
 /keycodemapdb
 /libvfio-user
 /slirp
+/proc-macro2-1.0.84
+/quote-1.0.36
+/syn-2.0.66
+/unicode-ident-1.0.12

subprojects/packagefiles/proc-macro2-1-rs/meson.build

@@ -0,0 +1,31 @@
+project('proc-macro2-1-rs', 'rust',
+  version: '1.0.84',
+  license: 'MIT OR Apache-2.0',
+  default_options: [])
+
+subproject('unicode-ident-1-rs', required: true)
+
+unicode_ident_dep = dependency('unicode-ident-1-rs', native: true)
+
+_proc_macro2_rs = static_library(
+  'proc_macro2',
+  files('src/lib.rs'),
+  gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
+  rust_abi: 'rust',
+  rust_args: [
+    '--cfg', 'feature="proc-macro"',
+    '--cfg', 'span_locations',
+    '--cfg', 'wrap_proc_macro',
+  ],
+  dependencies: [
+    unicode_ident_dep,
+  ],
+  native: true,
+)
+
+proc_macro2_dep = declare_dependency(
+  link_with: _proc_macro2_rs,
+)
+
+meson.override_dependency('proc-macro2-1-rs', proc_macro2_dep, native: true)

subprojects/packagefiles/quote-1-rs/meson.build

@@ -0,0 +1,29 @@
+project('quote-1-rs', 'rust',
+  version: '1.12.0',
+  license: 'MIT OR Apache-2.0',
+  default_options: [])
+
+subproject('proc-macro2-1-rs', required: true)
+
+proc_macro2_dep = dependency('proc-macro2-1-rs', native: true)
+
+_quote_rs = static_library(
+  'quote',
+  files('src/lib.rs'),
+  gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
+  rust_abi: 'rust',
+  rust_args: [
+    '--cfg', 'feature="proc-macro"',
+  ],
+  dependencies: [
+    proc_macro2_dep,
+  ],
+  native: true,
+)
+
+quote_dep = declare_dependency(
+  link_with: _quote_rs,
+)
+
+meson.override_dependency('quote-1-rs', quote_dep, native: true)

subprojects/packagefiles/syn-2-rs/meson.build

@@ -0,0 +1,40 @@
+project('syn-2-rs', 'rust',
+  version: '2.0.66',
+  license: 'MIT OR Apache-2.0',
+  default_options: [])
+
+subproject('proc-macro2-1-rs', required: true)
+subproject('quote-1-rs', required: true)
+subproject('unicode-ident-1-rs', required: true)
+
+proc_macro2_dep = dependency('proc-macro2-1-rs', native: true)
+quote_dep = dependency('quote-1-rs', native: true)
+unicode_ident_dep = dependency('unicode-ident-1-rs', native: true)
+
+_syn_rs = static_library(
+  'syn',
+  files('src/lib.rs'),
+  gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
+  rust_abi: 'rust',
+  rust_args: [
+    '--cfg', 'feature="full"',
+    '--cfg', 'feature="derive"',
+    '--cfg', 'feature="parsing"',
+    '--cfg', 'feature="printing"',
+    '--cfg', 'feature="clone-impls"',
+    '--cfg', 'feature="proc-macro"',
+  ],
+  dependencies: [
+    quote_dep,
+    proc_macro2_dep,
+    unicode_ident_dep,
+  ],
+  native: true,
+)
+
+syn_dep = declare_dependency(
+  link_with: _syn_rs,
+)
+
+meson.override_dependency('syn-2-rs', syn_dep, native: true)

subprojects/proc-macro2-1-rs.wrap

@@ -0,0 +1,7 @@
+[wrap-file]
+directory = proc-macro2-1.0.84
+source_url = https://crates.io/api/v1/crates/proc-macro2/1.0.84/download
+source_filename = proc-macro2-1.0.84.0.tar.gz
+source_hash = ec96c6a92621310b51366f1e28d05ef11489516e93be030060e5fc12024a49d6
+#method = cargo
+patch_directory = proc-macro2-1-rs

subprojects/quote-1-rs.wrap

@@ -0,0 +1,7 @@
+[wrap-file]
+directory = quote-1.0.36
+source_url = https://crates.io/api/v1/crates/quote/1.0.36/download
+source_filename = quote-1.0.36.0.tar.gz
+source_hash = 0fa76aaf39101c457836aec0ce2316dbdc3ab723cdda1c6bd4e6ad4208acaca7
+#method = cargo
+patch_directory = quote-1-rs

subprojects/syn-2-rs.wrap

@@ -0,0 +1,7 @@
+[wrap-file]
+directory = syn-2.0.66
+source_url = https://crates.io/api/v1/crates/syn/2.0.66/download
+source_filename = syn-2.0.66.0.tar.gz
+source_hash = c42f3f41a2de00b01c0aaad383c5a45241efc8b2d1eda5661812fda5f3cdcff5
+#method = cargo
+patch_directory = syn-2-rs

subprojects/unicode-ident-1-rs.wrap

@@ -0,0 +1,7 @@
+[wrap-file]
+directory = unicode-ident-1.0.12
+source_url = https://crates.io/api/v1/crates/unicode-ident/1.0.12/download
+source_filename = unicode-ident-1.0.12.tar.gz
+source_hash = 3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b
+#method = cargo
+patch_directory = unicode-ident-1-rs

subprojects/unicode-ident-1-rs/meson.build

@@ -0,0 +1,20 @@
+project('unicode-ident-1-rs', 'rust',
+  version: '1.0.12',
+  license: '(MIT OR Apache-2.0) AND Unicode-DFS-2016',
+  default_options: [])
+
+_unicode_ident_rs = static_library(
+  'unicode_ident',
+  files('src/lib.rs'),
+  gnu_symbol_visibility: 'hidden',
+  override_options: ['rust_std=2021', 'build.rust_std=2021'],
+  rust_abi: 'rust',
+  dependencies: [],
+  native: true,
+)
+
+unicode_ident_dep = declare_dependency(
+  link_with: _unicode_ident_rs,
+)
+
+meson.override_dependency('unicode-ident-1-rs', unicode_ident_dep, native: true)