{"id":145,"date":"2020-03-22T11:30:47","date_gmt":"2020-03-22T03:30:47","guid":{"rendered":"https:\/\/blog.tcx4c70.com\/?p=145"},"modified":"2022-06-10T21:06:31","modified_gmt":"2022-06-10T13:06:31","slug":"qom-1","status":"publish","type":"post","link":"https:\/\/blog.tcx4c70.com\/?p=145","title":{"rendered":"QOM\uff08QEMU Object Module\uff09\u6d45\u6790\uff08\u4e00\uff09"},"content":{"rendered":"\r\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\r\n<p>\u672c\u6587\u57fa\u4e8eQEMU 7.0\u3002<\/p>\r\n<\/blockquote>\r\n\r\n\r\n\r\n<p class=\"is-style-iw-2em\">QEMU\u4e2d\u540c\u4e00\u7c7b\u522b\u7684\u8bbe\u5907\u53ef\u80fd\u6709\u5f88\u591a\u79cd\uff0c\u5bf9\u4e8e\u540c\u7c7b\u4e0d\u540c\u79cd\u7684\u8bbe\u5907\uff0c\u9700\u8981\u8c03\u7528\u4e0d\u540c\u7684\u51fd\u6570\u8fdb\u884c\u76f8\u5e94\u7684\u5904\u7406\uff1b\u5e76\u4e14\uff0c\u540c\u4e00\u603b\u7ebf\u4e0b\u53ef\u80fd\u6302\u5728\u4e86\u5f88\u591a\u4e0d\u540c\u79cd\uff0c\u751a\u81f3\u4e0d\u540c\u7c7b\u522b\u7684\u8bbe\u5907\uff0c\u4e5f\u9700\u8981\u8c03\u7528\u4e0d\u540c\u7684\u51fd\u6570\u8fdb\u884c\u76f8\u5e94\u7684\u5904\u7406\u3002\u4e3a\u4e86\u80fd\u65b9\u4fbf\u7684\u5904\u7406\u8fd9\u4e9b\u60c5\u51b5\uff0c\u9762\u5411\u5bf9\u8c61\u7684\u601d\u60f3\u662f\u5fc5\u4e0d\u53ef\u5c11\u7684\u3002\u4e3a\u6b64\uff0cQEMU\u4e2d\u5b9e\u73b0\u4e86\u4e00\u5957\u9762\u5411\u5bf9\u8c61\u7684\u6a21\u578b\u2014\u2014QOM\uff08QEMU Object Module\uff09\u3002<\/p>\r\n\r\n\r\n\r\n<p class=\"is-style-iw-2em\">QOM\u5b9e\u73b0\u4e86\u7c7b\u4f3cJAVA\u7684\u5355\u6839\u7ee7\u627f\u7684\u7ed3\u6784\uff0c\u53ef\u5b9e\u73b0\u591a\u4e2a\u63a5\u53e3\uff0c\u5e76\u53ef\u5bf9\u5bf9\u8c61\u7684\u5c5e\u6027\u8fdb\u884c\u52a8\u6001\u7684\u589e\u52a0\u3001\u79fb\u9664\u3001\u4fee\u6539\u3002\u5176\u4e2d\u6bd4\u8f83\u91cd\u8981\u7684\u51e0\u4e2a\u7ed3\u6784\u5982\u4e0b\uff1a<\/p>\r\n\r\n\r\n\r\n<ul class=\"wp-block-list\">\r\n<li>Object: \u6240\u6709\u53ef\u5b9e\u4f8b\u5316\u7684\u5bf9\u8c61\u7684\u57fa\u7c7b\uff1b<\/li>\r\n<li>ObjectClass: \u6240\u6709\u7c7b\u5bf9\u8c61\u7684\u57fa\u7c7b\uff1b<\/li>\r\n<li>Interface: \u6240\u6709\u63a5\u53e3\u7684\u57fa\u7c7b\uff1b<\/li>\r\n<li>ObjectProperty: \u5bf9\u8c61\u53ef\u52a8\u6001\u589e\u52a0\u3001\u79fb\u9664\u3001\u4fee\u6539\u7684\u5c5e\u6027\uff1b<\/li>\r\n<li>TypeInfo: \u4fdd\u5b58\u5bf9\u5e94\u7c7b\u578b\u7684\u4fe1\u606f\uff08\u5305\u62ec\u7ee7\u627f\u5173\u7cfb\u3001\u5b9e\u73b0\u7684\u63a5\u53e3\u3001\u662f\u5426\u662f\u62bd\u8c61\u7c7b\u3001\u7c7b\u5bf9\u8c61\u7684\u521d\u59cb\u5316\u51fd\u6570\u3001\u5b9e\u4f8b\u7684\u521d\u59cb\u5316\u51fd\u6570\uff08\u6784\u9020\u51fd\u6570\uff1f\uff09\u7b49\uff09\uff1b<\/li>\r\n<li>TypeImpl: TypeInfo\u7684\u8fdb\u4e00\u6b65\u62bd\u8c61\uff0c\u4ee5\u6b64\u6765\u521d\u59cb\u5316\u5bf9\u5e94\u7684\u7c7b\u5bf9\u8c61\u53ca\u5bf9\u5e94\u7684\u793a\u4f8b\u3002\u8be5\u7ed3\u6784\u5bf9\u7528\u6237\u662f\u900f\u660e\u7684\uff0c\u7528\u6237\u53ea\u9700\u5b9a\u4e49TypeInfo\u3002<\/li>\r\n<\/ul>\r\n\r\n\r\n\r\n<p>\u6bcf\u4e2a\u7ed3\u6784\u7684\u5177\u4f53\u4fe1\u606f\u53ca\u5176\u5b57\u6bb5\u7684\u5177\u4f53\u542b\u4e49\u53ef\u5728<a href=\"https:\/\/gitlab.com\/qemu-project\/qemu\/-\/blob\/master\/include\/qom\/object.h\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"qemu\/include\/qom\/object.h\uff08\u5728\u65b0\u7a97\u53e3\u6253\u5f00\uff09\">qemu\/include\/qom\/object.h<\/a>\u4e2d\u67e5\u770b\u3002\u5b83\u4eec\u4e4b\u95f4\u7684\u5173\u7cfb\u5982\u4ee5\u4e0b\u7684UML\u6240\u793a\uff1a<\/p>\r\n\r\n<pre><p><figure class=\"mdx-lazyload-container\" style=\"\"><div style=\"padding-top:50%\"><\/div><div class=\"mdx-img-loading-sp mdui-valign\"><div><div class=\"mdui-spinner\"><\/div><\/div><\/div><img class=\"lazyload\" title=\"PlantUML Syntax:\r\nabstract class Object\r\nclass ObjectClass &lt;&lt; (S, #FF7700) Singleton &gt;&gt;\r\nclass InterfaceClass &lt;&lt; (S, #FF7700) Singleton &gt;&gt;\r\nclass UserCreatableClass &lt;&lt; (S, #FF7700) Singleton &gt;&gt;\r\ninterface Interface\r\ninterface UserCreatable\r\nObject -&gt; ObjectClass : class\r\nObject o--&gt; Object : parent\r\nObjectClass o-&gt; TypeImpl : type\r\nObject *--&gt; ObjectProperty : properties\r\nObjectClass *--&gt; ObjectProperty : properties\r\nObjectClass *--&gt; InterfaceClass : interfaces\r\nObjectClass &lt;|-- InterfaceClass\r\nObjectClass &lt;--o InterfaceClass : concrete_class\r\n\r\nTypeInfo *--&gt; InterfaceInfo : interfaces\r\nTypeImpl &lt;--o InterfaceClass: interface_type\r\nTypeImpl o--&gt; TypeImpl : parent_type\r\nTypeImpl o-&gt; ObjectClass : class\r\nTypeImpl *--&gt; InterfaceImpl : interfaces\r\nTypeImpl .&gt; TypeInfo\r\n\r\nInterfaceClass &lt;|-- UserCreatableClass\r\nInterface &lt;|-- UserCreatable\r\nInterface .&gt; InterfaceClass\r\nUserCreatable .&gt; UserCreatableClass\r\n\" src=\"data:image\/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==\" data-src=\"http:\/\/www.plantuml.com\/plantuml\/img\/dP8n2y8m48NtGlz3m4N5Y9iWfOiWE2ceiwJXb4fDIdABu8ytRMnCqWhYTirzzoxlDMd22esASIIyObgJNN43ZcdYVwtREil8-30ZeyrckLmi9kHGYci5A0N9yuxV2WHrOHn-7pbfK6i535bH_JHMTZi-s_p3G2zDh0D2yy3BohfrRKaTO7erKo2mQze9QO3ZeuRjlQuCWgPqqzFFz5x96XG-6XLRbg13fJ_eADOLSNOZEdjI6j4HGAdiot4fk0A4ypkLD6cjYekCzhT7uNeNoe2qHvvjOevk4_S2jPdtgI__pH7H_QpOuFtcxtt6GkCmVgfDSlstw743YD-TvxtW0xO1XlHV\" alt=\"PlantUML Syntax:\r\nabstract class Object\r\nclass ObjectClass &lt;&lt; (S, #FF7700) Singleton &gt;&gt;\r\nclass InterfaceClass &lt;&lt; (S, #FF7700) Singleton &gt;&gt;\r\nclass UserCreatableClass &lt;&lt; (S, #FF7700) Singleton &gt;&gt;\r\ninterface Interface\r\ninterface UserCreatable\r\nObject -&gt; ObjectClass : class\r\nObject o--&gt; Object : parent\r\nObjectClass o-&gt; TypeImpl : type\r\nObject *--&gt; ObjectProperty : properties\r\nObjectClass *--&gt; ObjectProperty : properties\r\nObjectClass *--&gt; InterfaceClass : interfaces\r\nObjectClass &lt;|-- InterfaceClass\r\nObjectClass &lt;--o InterfaceClass : concrete_class\r\n\r\nTypeInfo *--&gt; InterfaceInfo : interfaces\r\nTypeImpl &lt;--o InterfaceClass: interface_type\r\nTypeImpl o--&gt; TypeImpl : parent_type\r\nTypeImpl o-&gt; ObjectClass : class\r\nTypeImpl *--&gt; InterfaceImpl : interfaces\r\nTypeImpl .&gt; TypeInfo\r\n\r\nInterfaceClass &lt;|-- UserCreatableClass\r\nInterface &lt;|-- UserCreatable\r\nInterface .&gt; InterfaceClass\r\nUserCreatable .&gt; UserCreatableClass\r\n\"><\/figure><\/p><\/pre>\r\n\r\n<p>\u82e5\u60f3\u8981\u65b0\u589e\u4e00\u79cd\u7c7b\uff0c\u5219\u9700\u8981\u5b9e\u73b0\u4ee5\u4e0b\u51e0\u4e2a\u7ed3\u6784\u4f53\uff1a<\/p>\r\n<ul>\r\n<li>\u65b0\u589e\u4e00\u4e2a<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">Object<\/code>\uff1a\u82e5\u4e3a\u63a5\u53e3\uff0c\u5219\u53ea\u9700<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">typedef<\/code>\u4e00\u4e0b\u5373\u53ef\uff0c\u5982<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">typedef struct MyInterface MyInterface;<\/code>\uff1b\u5426\u5219\u7684\u8bdd\uff0c\u8be5\u7ed3\u6784\u4f53\u4e2d\u653e\u7f6e\u5bf9\u8c61\u7684\u5404\u79cd\u5404\u6210\u5458\u53d8\u91cf\uff0c\u5176\u4e2d\u7b2c\u4e00\u4e2a\u6210\u5458\u5fc5\u987b\u662f<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">Object<\/code>\u6216\u5176\u5b50\u7c7b\uff1b<\/li>\r\n<li>\u65b0\u589e\u4e00\u4e2a<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\uff1a\u8be5\u7ed3\u6784\u4f53\u653e\u7f6e\u5bf9\u8c61\u7684\u5404\u79cd\u6210\u5458\u51fd\u6570\u548c\u7c7b\u6210\u5458\u53d8\u91cf\uff0c\u5176\u4e2d\u7b2c\u4e00\u4e2a\u6210\u5458\u5fc5\u987b\u662f<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u6216\u5176\u5b50\u7c7b\uff08\u82e5\u4e3a\u63a5\u53e3\uff0c\u5219\u7b2c\u4e00\u4e2a\u6210\u5458\u5fc5\u987b\u662f<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">Interface<\/code>\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\uff1a\u8be5\u7ed3\u6784\u4f53\u4e3b\u8981\u7528\u4e8e\u6ce8\u518c\u8be5\u7c7b\u7684typename\u3001\u7ee7\u627f\u5173\u7cfb\u3001\u6784\u9020\u6790\u6784\u51fd\u6570\u7b49\u3002<\/li>\r\n<\/ul>\r\n<h1 class=\"wp-block-heading\">QOM\u4e2d\u9762\u5411\u5bf9\u8c61\u7684\u7279\u6027<\/h1>\r\n\r\n\r\n\n<hr class=\"wp-block-separator is-style-default\"\/>\n\r\n\r\n\r\n<p class=\"is-style-iw-2em\">\u5229\u7528QOM\uff0cQEMU\u5b9e\u73b0\u4e86\u5728C\u8bed\u8a00\u4e2d\u7f16\u5199\u9762\u5411\u5bf9\u8c61\u98ce\u683c\u7684\u4ee3\u7801\u3002\u867d\u7136\u4f7f\u7528\u8d77\u6765\uff0c\u4e0eC++\u3001JAVA\u8fd9\u79cd\u539f\u751f\u652f\u6301\u9762\u5411\u5bf9\u8c61\u7684\u8bed\u8a00\u7565\u590d\u6742\u4e86\u4e9b\uff0c\u4f46\u81f3\u5c11\u5c01\u88c5\u3001\u7ee7\u627f\u3001\u591a\u6001\u4e09\u5927\u9762\u5411\u5bf9\u8c61\u7684\u7279\u6027\u90fd\u53ef\u4ee5\u5b9e\u73b0\u3002<\/p>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">\u5c01\u88c5<\/h2>\r\n\r\n\r\n\r\n<p class=\"is-style-iw-2em\">\u5c01\u88c5\u81ea\u4e0d\u7528\u8bf4\uff0cC\u8bed\u8a00\u4e2d\u7684\u7ed3\u6784\u4f53\u5c31\u80fd\u5b9e\u73b0\u5c01\u88c5\uff1b\u5f53\u7136\uff0c \u50cf<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">public<\/code>\u3001<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">protected<\/code>\u3001<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">private<\/code>\u8fd9\u79cd\u8bbf\u95ee\u5c5e\u6027\u662f\u6ca1\u6cd5\u5b9e\u73b0\u4e86\uff0c\u867d\u8bf4\u5c06\u5bf9\u8c61\u4e2d\u90e8\u5206\u6570\u636e\u7684\u7c7b\u578b\u5b9a\u4e49\u653e\u5230<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">.c<\/code>\u6587\u4ef6\u4e2d\u6216\u5c06\u6570\u636e\u5b9a\u4e49\u4e3a<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">void *opaque<\/code>\u4e5f\u80fd\u5b9e\u73b0\u7c7b\u4f3cprivate\u7684\u80fd\u529b\uff0c\u4f46\u662f\u8fd9\u6837\u4ee3\u7801\u7684\u53ef\u9605\u8bfb\u6027\u548c\u53ef\u7ef4\u62a4\u6027\u5c31\u5927\u5927\u964d\u4f4e\u4e86\uff0c\u56e0\u6b64\u5bf9\u4e8e\u6570\u636e\u8bbf\u95ee\u5c5e\u6027\u7684\u63a7\u5236\u66f4\u591a\u8fd8\u662f\u9760\u4ee3\u7801\u4e2d\u7684\u7ea6\u5b9a\u3002\u5982<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">DeviceState<\/code>\u5b9a\u4e49\u4e2d\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">parent_obj<\/code>\u662f<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">private<\/code>\u7684\uff0c\u4f60\u4e0d\u5e94\u8be5\u76f4\u63a5\u8bbf\u95ee\u5b83\u3002<\/p>\r\n\r\n\r\n\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"c\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">struct DeviceState {\r\n    \/*&lt; private &gt;*\/\r\n    Object parent_obj;\r\n    \/*&lt; public &gt;*\/\r\n\r\n    const char *id;\r\n    char *canonical_path;\r\n    bool realized;\r\n    bool pending_deleted_event;\r\n    QemuOpts *opts;\r\n    int hotplugged;\r\n    BusState *parent_bus;\r\n    QLIST_HEAD(, NamedGPIOList) gpios;\r\n    QLIST_HEAD(, BusState) child_bus;\r\n    int num_child_bus;\r\n    int instance_id_alias;\r\n    int alias_required_for_version;\r\n};<\/pre>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">\u7ee7\u627f<\/h2>\r\n\r\n\r\n\r\n<p class=\"is-style-iw-2em\">\u7ee7\u627f\u5206\u4e3a\u5bf9\u7c7b\u7684\u6cdb\u5316\u548c\u5bf9\u63a5\u53e3\u7684\u5b9e\u73b0\uff0c\u8fd9\u4e24\u8005\u5728QOM\u4e2d\u4e3b\u8981\u662f\u901a\u8fc7\u5b9a\u4e49\u7ed3\u6784\u4f53<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u4e2d\u7684\u6210\u5458\u5b9e\u73b0\u7684\u3002\u5728<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u4e2d\u901a\u8fc7\u6307\u5b9a<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">name<\/code>\u548c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">parent<\/code>\u5206\u522b\u6307\u5b9a\u8be5\u7c7b\u53ca\u5176\u7236\u7c7b\u7684\u540d\u5b57\uff08\u5e94\u8be5\u8bf4\u662ftype name\u6216\u8005type id\uff0c\u9700\u4fdd\u8bc1\u5168\u5c40\u552f\u4e00\uff09\uff0c\u5728<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">interfaces<\/code>\u4e2d\u6307\u5b9a\u8be5\u7c7b\u5b9e\u73b0\u7684\u63a5\u53e3\u7684\u540d\u5b57\u3002\u540c\u65f6\uff0c\u4e3a\u4e86\u5411\u4e0a\u7c7b\u578b\u8f6c\u6362\u548c\u5411\u4e0b\u7c7b\u578b\u8f6c\u6362\u65b9\u4fbf\uff0c\u8fd8\u9700\u8981\u5206\u522b\u5c06\u8be5\u7c7b\u7236\u7c7b\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">Object<\/code>\u548c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u7ed3\u6784\u4f53\u4f5c\u4e3a\u8be5\u7c7b\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">Object<\/code>\u548c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u7ed3\u6784\u4f53\u4e2d\u7684\u9996\u4f4d\u6210\u5458\u3002<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"java\">interface Interface0 {\r\n}\r\n\r\ninterface Interface1 {\r\n}\r\n\r\nabstract class Base extends Object {\r\n}\r\n\r\nclass Derived0 extends Base implements Interface0 {\r\n}\r\n\r\nclass Derived1 extends Base implements Interface0, Interface1 {\r\n}<\/pre>\r\n<p><a id=\"inheritance-example-code\"><\/a>\u4f8b\u5982\uff0c\u4e0a\u8ff0Java\u4ee3\u7801\u201c\u7b49\u4ef7\u201d\u4e0b\u9762\u7528QOM\u5b9e\u73b0\u7684\u4ee3\u7801\uff1a<\/p>\r\n\r\n\r\n\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"c\" data-enlighter-theme=\"\" data-enlighter-highlight=\"\" data-enlighter-linenumbers=\"\" data-enlighter-lineoffset=\"\" data-enlighter-title=\"\" data-enlighter-group=\"\">typedef struct Interface0 Interface0;\r\ntypedef struct Interface0Class {\r\n    InterfaceClass parent_class;\r\n};\r\nstatic const TypeInfo interface0_info {\r\n    .name   = \"Interface0\",\r\n    .parent = TYPE_INTERFACE,\r\n};\r\n\r\ntypedef struct Interface1 Interface1;\r\ntypedef struct Interface1Class {\r\n    InterfaceClass parent_class;\r\n};\r\nstatic const TypeInfo interface1_info {\r\n    .name   = \"Interface1\",\r\n    .parent = TYPE_INTERFACE,\r\n};\r\n\r\ntypedef struct Base {\r\n    Object parent_obj;\r\n};\r\ntypedef struct BaseClass {\r\n    ObjectClass parent_class;\r\n};\r\nstatic const TypeInfo base_info {\r\n    .name     = \"Base\",\r\n    .parent   = TYPE_OBJECT,\r\n    .abstract = true,\r\n};\r\n\r\ntypedef struct Drived0 {\r\n    Base parent_obj;\r\n};\r\ntypedef struct Drived0Class {\r\n    BaseClass parent_class;\r\n};\r\nstatic const TypeInfo drived0_info {\r\n    .name          = \"Drived0\",\r\n    .parent        = \"Base\",\r\n    .instance_size = sizeof(Drived0),\r\n    .interfaces    = (InterfaceInfo[]) {\r\n        { \"Interface0\" },\r\n        { },\r\n    },\r\n};\r\n\r\ntypedef struct Drived1 {\r\n    Base parent_obj;\r\n};\r\ntypedef struct Drived1Class {\r\n    BaseClass parent_class;\r\n};\r\nstatic const TypeInfo drived1_info {\r\n    .name          = \"Drived1\",\r\n    .parent        = \"Base\",\r\n    .instance_size = sizeof(Drived1),\r\n    .interfaces    = (InterfaceInfo[]) {\r\n        { \"Interface0\" },\r\n        { \"Interface1\" },\r\n        { },\r\n    },\r\n};<\/pre>\r\n\r\n\r\n\r\n<p>\u8bf4\u5230\u7ee7\u627f\u5c31\u4e0d\u5f97\u4e0d\u8bf4\u4e00\u4e0b\u7c7b\u578b\u8f6c\u6362\uff0c\u5c24\u5176\u662f\u5b89\u5168\u7684\u5411\u4e0b\u7c7b\u578b\u8f6c\u6362\u3002\u7531\u4e8eQEMU\u672c\u8eab\u4f7f\u7528C\u8bed\u8a00\u5b9e\u73b0\u7684\uff0c\u800cC\u8bed\u8a00\u672c\u8eab\u4e0d\u652f\u6301OO\uff0c\u56e0\u6b64\u4e0d\u80fd\u50cfC++\u6216JAVA\u90a3\u6837\u4f7f\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">.<\/code>\u548c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">-&gt;<\/code>\u8bbf\u95ee\u7236\u7c7b\u7684\u6210\u5458\uff0c\u53ea\u80fd\u5148\u5c06\u5bf9\u8c61\u5411\u4e0a\u8f6c\u6362\u4e3a\u7236\u7c7b\u5bf9\u8c61\uff0c\u7136\u540e\u518d\u8bbf\u95ee\u7236\u7c7b\u7684\u6210\u5458\u3002\u6b64\u5916\uff0cC\u8bed\u8a00\u4e5f\u65e0\u6cd5\u505a\u5230\u7ed9\u6210\u5458\u51fd\u6570\u81ea\u52a8\u4f20\u9012this\u6307\u9488\uff08\u6216\u5176\u4ed6\u7c7b\u4f3c\u7684\u6982\u5ff5\uff09\uff0c\u53ea\u80fd\u518d\u6210\u5458\u51fd\u6570\u7684\u53c2\u6570\u4e2d\u589e\u52a0\u4e00\u4e2a\u6307\u5411\u8be5\u5bf9\u8c61\u7684\u6307\u9488\uff0c\u8c03\u7528\u65f6\u624b\u52a8\u4f20\u9012\u8be5\u5bf9\u8c61\u7684\u6307\u9488\uff0c\u800c\u8fd9\u4e2a\u53c2\u6570\u7c7b\u578b\u53ea\u80fd\u4e3a\u6307\u5411\u7236\u7c7b\u7684\u6307\u9488\u3002\u82e5\u5b50\u7c7b\u4e2d\u7684override\u8fd9\u4e2a\u6210\u5458\u51fd\u6570\uff0c\u5e38\u5e38\u9700\u8981\u8bbf\u95ee\u5b50\u7c7b\u7684\u6210\u5458\uff0c\u56e0\u6b64\u9700\u8981\u5c06\u8be5\u53c2\u6570\u5411\u4e0b\u8f6c\u6362\u4e3a\u6307\u5411\u5b50\u7c7b\u7684\u6307\u9488\u3002\u7531\u4e8e\u4ee5\u4e0a\u4e24\u70b9\u539f\u56e0\uff0cQEMU\u4e2d\u6d89\u53ca\u5230QOM\u7684\u4ee3\u7801\u4e2d\u7c7b\u578b\u8f6c\u6362\u7684\u6b21\u6570\u975e\u5e38\u591a\u3002QOM\u4e2d\u4e3a\u4e86\u80fd\u66f4\u65b9\u4fbf\u3001\u5b89\u5168\u5730\u8fdb\u884c\u7c7b\u578b\u8f6c\u6362\uff0c\u63d0\u4f9b\u4e86\u4e0b\u9762\u7684helper \u51fd\u6570\uff1a<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">\/**\r\n * object_dynamic_cast:\r\n * @obj: The object to cast.\r\n * @typename: The @typename to cast to.\r\n *\r\n * This function will determine if @obj is-a @typename.  @obj can refer to an\r\n * object or an interface associated with an object.\r\n *\r\n * Returns: This function returns @obj on success or #NULL on failure.\r\n *\/\r\nObject *object_dynamic_cast(Object *obj, const char *typename);\r\n\r\n\/**\r\n * object_dynamic_cast_assert:\r\n *\r\n * See object_dynamic_cast() for a description of the parameters of this\r\n * function.  The only difference in behavior is that this function asserts\r\n * instead of returning #NULL on failure if QOM cast debugging is enabled.\r\n * This function is not meant to be called directly, but only through\r\n * the wrapper macro OBJECT_CHECK.\r\n *\/\r\nObject *object_dynamic_cast_assert(Object *obj, const char *typename,\r\n                                   const char *file, int line, const char *func);<\/pre>\r\n<p>\u8fd9\u4e24\u4e2a\u51fd\u6570\u90fd\u53ef\u4ee5\u8fdb\u884c\u5b89\u5168\u7684\u52a8\u6001\u7c7b\u578b\u8f6c\u6362\uff0c\u4f46\u4e3b\u8981\u6709\u4ee5\u4e0b2\u70b9\u4e0d\u540c\uff1a<\/p>\r\n<ol>\r\n<li>\u5f53<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">obj<\/code>\u4e0d\u662f\u6307\u5411<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">typename<\/code>\u7c7b\u578b\u7684\u6307\u9488\u65f6\uff0c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_dynamic_cast<\/code>\u4f1a\u8fd4\u56de<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">NULL<\/code>\uff1b\u800c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_dynamic_cast_assert<\/code>\u5219\u4f1a\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">assert()<\/code>\u4f7f\u5f97\u5f53\u524d\u7a0b\u5e8f\u9000\u51fa\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_dynamic_cast<\/code>\u53ea\u662f\u505a\u4e86\u7c7b\u578b\u68c0\u67e5\uff0c\u800c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_dynamic_cast_assert<\/code>\u9664\u6b64\u4e4b\u5916\u8fd8\u5c06\uff08\u6210\u529f\u7684\uff09\u7c7b\u578b\u8f6c\u6362\u7684\u7ed3\u679c\u7f13\u5b58\u4e86\u4e0b\u6765\u4ee5\u4f9b\u4e0b\u6b21\u7c7b\u578b\u8f6c\u6362\u4f7f\u7528\u3002\u56e0\u6b64\uff0c\u5f53\u67d0\u79cd\u7c7b\u578b\u9891\u7e41\u5730\u8f6c\u6362\u4e3a\u53e6\u4e00\u79cd\u7c7b\u578b\u65f6\uff0c\u4f7f\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_dynamic_cast_assert<\/code>\u4f1a\u66f4\u5feb\u3002<\/li>\r\n<\/ol>\r\n<p>\u7531\u4e8e\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u5f53<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">obj<\/code>\u4e0d\u662f\u6211\u4eec\u671f\u671b\u7684\u7c7b\u578b\u65f6\uff0c\u8bf4\u660e\u4ee3\u7801\u903b\u8f91\u51fa\u4e86\u95ee\u9898\uff0c\u6211\u4eec\u65e0\u6cd5\u8fdb\u884c\u8fdb\u4e00\u6b65\u7684\u5904\u7406\uff0c\u53ea\u80fd\u9000\u51fa\u7a0b\u5e8f\uff0c\u56e0\u6b64<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_dynamic_cast_assert<\/code>\u66f4\u5e38\u7528\u4e00\u4e9b\u3002\u800cQOM\u4e5f\u7528\u5b8f\u5c01\u88c5\u4e86\u8fd9\u4e2a\u51fd\u6570\uff0c\u65b9\u4fbf\u6211\u4eec\u8c03\u7528\uff1a<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">\/**\r\n * OBJECT_CHECK:\r\n * @type: The C type to use for the return value.\r\n * @obj: A derivative of @type to cast.\r\n * @name: The QOM typename of @type\r\n *\r\n * A type safe version of @object_dynamic_cast_assert.  Typically each class\r\n * will define a macro based on this type to perform type safe dynamic_casts to\r\n * this object type.\r\n *\r\n * If an invalid object is passed to this function, a run time assert will be\r\n * generated.\r\n *\/\r\n#define OBJECT_CHECK(type, obj, name) \\\r\n    ((type *)object_dynamic_cast_assert(OBJECT(obj), (name), \\\r\n                                        __FILE__, __LINE__, __func__))<\/pre>\r\n<p>\u4e00\u822c\u5730\uff0c\u6bcf\u4e00\u79cdQOM\u5bf9\u8c61\u90fd\u4f1a\u5bf9<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">OBJECT_CHECK<\/code>\u518d\u6b21\u5c01\u88c5\uff0c\u5982<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">#define ARM_CPU(obj) OBJECT_CHECK(ARMCPU, (obj), TYPE_ARM_CPU)<\/code>\u3002<\/p>\r\n\r\n\r\n\r\n<h2 class=\"wp-block-heading\">\u591a\u6001<\/h2>\r\n\r\n\r\n\r\n<p class=\"is-style-iw-2em\">\u6bcf\u4e2a\u7c7b\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u7ed3\u6784\u4f53\u7c7b\u4f3cC++\u4e2d\u7684\u865a\u51fd\u6570\u8868\u548c\u7c7b\u6210\u5458\u53d8\u91cf\uff0c\u56e0\u6b64QOM\u4e2d\u591a\u6001\u7684\u5b9e\u73b0\u5173\u952e\u5c31\u662f\u5982\u4f55\u6b63\u786e\u5730\u521d\u59cb\u5316<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u4e2d\u7684\u51fd\u6570\u6307\u9488\u3002\u8fd9\u4e00\u6b65\u662f\u5728<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u4e2d\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_init<\/code>\u56de\u8c03\u51fd\u6570\u4e2d\u5b9e\u73b0\u7684\uff0c\u5728\u6bcf\u4e2a\u7c7b\u7684\u7b2c\u4e00\u4e2a\u5b9e\u4f8b\u521d\u59cb\u5316\u65f6\uff0c\u4f1a\u8c03\u7528\u5bf9\u5e94\u7c7b\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_init<\/code>\u56de\u8c03\u51fd\u6570\u5148\u521d\u59cb\u5316<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u3002\u7531\u4e8e\u7236\u7c7b\u548c\u5b50\u7c7b<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">Object<\/code>\u4e2d\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class<\/code>\u4f1a\u6307\u5411\u4e0d\u540c\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\uff0c\u56e0\u6b64\u82e5\u5b50\u7c7b\u60f3\u8981\u91cd\u5199\uff08override\uff09\u7236\u7c7b\u4e2d\u7684\u51fd\u6570\uff0c\u53ea\u9700\u8981\u5728<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_init<\/code>\u56de\u8c03\u51fd\u6570\u4e2d\u5c06<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">ObjectClass<\/code>\u4e2d\u76f8\u5e94\u7684\u6210\u5458\u51fd\u6570\u8d4b\u503c\u4e3a\u5b50\u7c7b\u81ea\u5df1\u5b9e\u73b0\u7684\u51fd\u6570\u5373\u53ef\u3002<\/p>\r\n\r\n\r\n\r\n<h1 class=\"wp-block-heading\">\u6784\u9020<\/h1>\r\n\r\n\r\n\n<hr class=\"wp-block-separator is-style-default\"\/>\n\r\n\r\n\r\n<p>\u5728QOM\u4e2d\uff0c\u5bf9\u8c61\u7684\u6784\u9020\uff08\u521d\u59cb\u5316\uff09\u5206\u4e3a\u4ee5\u4e0b4\u6b65\uff1a<\/p>\r\n<ol>\r\n<li>\u6ce8\u518c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\uff1b<\/li>\r\n<li>\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u6ce8\u518c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\uff1b<\/li>\r\n<li>\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\u6784\u9020\u7c7b\u5bf9\u8c61\uff1b<\/li>\r\n<li>\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\u6784\u9020\u5bf9\u8c61\u3002<\/li>\r\n<\/ol>\r\n<p>\u5176\u4e2d\uff0c\u5bf9\u4e8e\u540c\u4e00\u79cd\u5bf9\u8c61\u7684\u591a\u4e2a\u5b9e\u4f8b\u6765\u8bf4\uff0c1~3\u6b65\u53ea\u4f1a\u6267\u884c\u4e00\u6b21\u3002\u6bd4\u5982\uff0c\u5728\u7b2c\u4e00\u6b21\u6784\u9020<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TYPE_ARM_HOST_CPU<\/code>\u5bf9\u8c61\u65f6\uff0c1~4\u6b65\u90fd\u4f1a\u6267\u884c\uff1b\u800c\u4e4b\u540e\u518d\u6b21\u6784\u9020<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TYPE_ARM_HOST_CPU<\/code>\u5bf9\u8c61\u65f6\uff0c\u5219\u53ea\u4f1a\u6267\u884c\u7b2c4\u6b65\u3002<\/p>\r\n<h2>\u6ce8\u518c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code><\/h2>\r\n<p>\u7531\u4e8eC\u8bed\u8a00\u672c\u8eab\u4e0d\u652f\u6301OO\uff0c\u65e0\u6cd5\u50cf\u5728JAVA\u4e2d\u7528\u7c7b\u4f3c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"java\">class Derived0 extends Base implements Interface0<\/code>\u7684\u65b9\u5f0f\u58f0\u660e\u4e00\u4e2a\u7c7b\u5e76\u6307\u5b9a\u7ee7\u627f\u5173\u7cfb\u3001\u5b9e\u73b0\u5173\u7cfb\u7b49\uff0c\u56e0\u6b64\u82e5\u8981\u5728C\u8bed\u8a00\u4e2d\u5b9e\u73b0OO\u5219\u5fc5\u987b\u8981\u6709\u6570\u636e\u7ed3\u6784\u6765\u4fdd\u5b58\u8fd9\u4e9b\u4fe1\u606f\u3002\u5728QOM\u4e2d\uff0c\u8fd9\u90e8\u5206\u4fe1\u606f\u9700\u8981\u5229\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u8fd9\u4e2a\u7ed3\u6784\u4f53\u6765\u63d0\u4f9b\u3002<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u5177\u4f53\u7684\u5b57\u6bb5\u53ca\u5176\u542b\u4e49\u5982\u4e0b\uff1a<\/p>\r\n<ul>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">name<\/code>\uff1a\u8be5\u7c7b\u7684typename\uff0c\u5fc5\u987b\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">parent<\/code>\uff1a\u7236\u7c7b\u7684typename\uff0c\u5fc5\u987b\uff1a<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">abstract<\/code>\uff1a\u662f\u5426\u4e3a\u62bd\u8c61\u7c7b\uff0c\u82e5\u4e3a\u62bd\u8c61\u7c7b\u5219\u4e0d\u80fd\u5b9e\u4f8b\u5316\uff08\u9ed8\u8ba4\u4e0d\u662f\u62bd\u8c61\u7c7b\uff09\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_size<\/code>\uff1a\u7c7b\u5bf9\u8c61\u7684\u5927\u5c0f\uff0c\u82e5\u4e3a0\u5219\u4e0e\u7236\u7c7b\u7c7b\u5bf9\u8c61\u7684\u5927\u5c0f\u76f8\u540c\uff08\u9ed8\u8ba4\u4e0e\u7236\u7c7b\u7c7b\u5bf9\u8c61\u5927\u5c0f\u76f8\u540c\uff09\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_init<\/code>\uff1a\u7c7b\u5bf9\u8c61\u6784\u9020\u51fd\u6570\uff0c\u865a\u51fd\u6570\u8868\u7684\u521d\u59cb\u5316\u9700\u5728\u6b64\u5b8c\u6210\uff1bQOM\u4e2d\u8c03\u7528\u987a\u5e8f\u4e3a\u5148\u8c03\u7528\u7236\u7c7b\u7c7b\u5bf9\u8c61\u7684\u6784\u9020\u51fd\u6570\uff0c\u518d\u8c03\u7528\u5b50\u7c7b\u7c7b\u5bf9\u8c61\u7684\u6784\u9020\u51fd\u6570\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_base_init<\/code>\uff1a\u5728\u6784\u9020\u5b50\u7c7b\u7c7b\u5bf9\u8c61\u65f6\uff0c\u5148\u6784\u9020\u7236\u7c7b\u7c7b\u5bf9\u8c61\uff0c\u7136\u540e\u5c06\u7236\u7c7b\u7c7b\u5bf9\u8c61\u62f7\u8d1d\u5230\u5b50\u7c7b\u7c7b\u5bf9\u8c61\u4e2d\uff0c\u800c\u8fd9\u79cd\u5185\u5b58\u62f7\u8d1d\u53ef\u80fd\u4f1a\u9020\u6210\u526f\u4f5c\u7528\uff0c\u6b64\u65f6<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_base_init<\/code>\u53ef\u7528\u6765\u62b5\u6d88\u8fd9\u79cd\u526f\u4f5c\u7528\uff1bQOM\u4e2d\u4f1a\u5728\u8c03\u7528\u5b8c\u6240\u6709\u7236\u7c7b\u7c7b\u5bf9\u8c61\u6784\u9020\u51fd\u6570\u4e4b\u540e\u3001\u8c03\u7528\u5b50\u7c7b\u7c7b\u5bf9\u8c61\u6784\u9020\u51fd\u6570\u4e4b\u524d\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_base_init<\/code>\uff0c\u8c03\u7528\u987a\u5e8f\u4e3a\u6309\u7167\u4ece\u5b50\u7c7b\u5230\u7236\u7c7b\u7684\u987a\u5e8f\u8c03\u7528\u6240\u6709\u7236\u7c7b\u7c7b\u5bf9\u8c61\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_base_init<\/code>\uff08\u4f46\u4e0d\u4f1a\u8c03\u7528\u672c\u8eab\u7c7b\u5bf9\u8c61\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_base_init<\/code>\uff09\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_data<\/code>\uff1a\u4f20\u9012\u7ed9\u7c7b\u5bf9\u8c61\u6784\u9020\u51fd\u6570<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_init<\/code>\u548c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">class_base_init<\/code>\u7684\u5165\u53c2\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">interfaces<\/code>\uff1a\u8be5\u7c7b\u5b9e\u73b0\u7684\u63a5\u53e3\u5217\u8868\uff0c\u5217\u8868\u6700\u540e\u4e00\u4e2a\u5143\u7d20\u9700\u4e3a\u7a7a\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_size<\/code>\uff1a\u5b9e\u4f8b\u7684\u5927\u5c0f\uff0c\u82e5\u4e3a0\u5219\u4e0e\u7236\u7c7b\u5b9e\u4f8b\u7684\u5927\u5c0f\u76f8\u540c\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_init<\/code>\uff1a\u5b9e\u4f8b\u6784\u9020\u51fd\u6570\uff0c\u4e0eOO\u8bed\u8a00\u76f8\u540c\uff0c\u9664\u975e\u4e0e\u7236\u7c7b\u6210\u5458\u53d8\u91cf\u521d\u59cb\u5316\u7684\u503c\u4e0d\u540c\uff0c\u5426\u5219\u53ea\u9700\u521d\u59cb\u5316\u5b50\u7c7b\u7684\u6210\u5458\u53d8\u91cf\u5373\u53ef\uff1bQOM\u4e2d\u8c03\u7528\u987a\u5e8f\u4e3a\u5148\u8c03\u7528\u7236\u7c7b\u5b9e\u4f8b\u7684\u6784\u9020\u51fd\u6570\uff0c\u518d\u8c03\u7528\u5b50\u7c7b\u5b9e\u4f8b\u7684\u6784\u9020\u51fd\u6570\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_post_init<\/code>\uff1a\u5728\u8c03\u7528\u5b8c\u6240\u6709\u7684\u6784\u9020\u51fd\u6570\u540e\uff0c\u4f1a\u8c03\u7528\u5b50\u7c7b\u53ca\u7236\u7c7b\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_post_init<\/code>\u6765\u7ed3\u675f\u521d\u59cb\u5316\u7684\u6d41\u7a0b\uff1bQOM\u4e2d\u4f1a\u5728\u8c03\u7528\u5b8c\u6210\u6240\u6709\u6784\u9020\u51fd\u6570\u540e\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_post_init<\/code>\uff0c\u987a\u5e8f\u4e3a\u5148\u8c03\u7528\u5b50\u7c7b\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_post_init<\/code>\uff0c\u518d\u8c03\u7528\u7236\u7c7b\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_post_init<\/code>\uff1b<\/li>\r\n<li><code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_finalize<\/code>\uff1a\u5b9e\u4f8b\u6790\u6784\u51fd\u6570\uff0c\u4e0eOO\u8bed\u8a00\u76f8\u540c\uff0c\u53ea\u9700\u91ca\u653e\u5b50\u7c7b\u7684\u6210\u5458\u53d8\u91cf\uff0c\u4e0d\u9700\u91ca\u653e\u7236\u7c7b\u5b9e\u4f8b\u7684\u6210\u5458\u53d8\u91cf\uff0c\u4e5f\u4e0d\u9700\u91ca\u653e\u5b50\u7c7b\u5b9e\u4f8b\uff08\u5426\u5219\u4f1a\u9020\u6210double free\uff09\uff1bQOM\u4e2d\u8c03\u7528\u987a\u5e8f\u4e3a\u5148\u8c03\u7528\u5b50\u7c7b\u5b9e\u4f8b\u7684\u6790\u6784\u51fd\u6570\uff0c\u518d\u8c03\u7528\u7236\u7c7b\u5b9e\u4f8b\u7684\u6790\u6784\u51fd\u6570\u3002<\/li>\r\n<\/ul>\r\n<p>\u7528\u6237\u8fd8\u9700\u8981\u901a\u8fc7<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_register_static<\/code>\u548c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_init<\/code>\u6765\u6ce8\u518c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeInfo<\/code>\u3002\u6bd4\u5982\u4e0a\u6587<a href=\"#inheritance-example-code\">\u7ee7\u627f<\/a>\u4e2d\u793a\u4f8b\u4ee3\u7801\u4e2d\u7684\u7c7b\u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u65b9\u5f0f\u6765\u6ce8\u518c\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeInfo<\/code>\uff1a<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">static void register_types(void)\r\n{\r\n    type_resgister_static(&amp;interface0_info);\r\n    type_resgister_static(&amp;interface1_info);\r\n    type_resgister_static(&amp;base_info);\r\n    type_resgister_static(&amp;drived0_info);\r\n    type_resgister_static(&amp;drived1_info);\r\n}\r\ntype_init(register_types)<\/pre>\r\n<h2>\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u6ce8\u518c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code><\/h2>\r\n<p>\u4e0a\u4e00\u8282\u4e2d<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_register_static<\/code>\u4f1a\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeInfo<\/code>\u751f\u6210\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeImpl<\/code>\u5e76\u5c06\u5176\u52a0\u5165\u5230\u5168\u5c40\u7684\u54c8\u5e0c\u8868\u4e2d\uff0c\u4fbf\u4e8e\u540e\u7eed\u6839\u636e\u7c7b\u578b\u540d\uff08\u5373<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeInfo<\/code>\u4e2d\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">name<\/code>\uff09\u67e5\u627e\u5230\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeImpl<\/code>\uff0c\u800c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeImpl<\/code>\u624d\u662f\u771f\u6b63\u4fdd\u5b58\u7c7b\u578b\u4fe1\u606f\u7684\u7ed3\u6784\uff0c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeInfo<\/code>\u53ea\u662f\u4e3a\u4e86\u65b9\u4fbf\u5f00\u53d1\u8005\u3002\u800c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_init<\/code>\u5219\u662f\u6ce8\u518c\u5bf9\u5e94\u7684register\u51fd\u6570\uff0c\u4f46\u6ca1\u6709\u8c03\u7528\u8fd9\u4e2a\u51fd\u6570\uff08<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_init<\/code>\u662f\u901a\u8fc7\u5b8f\u751f\u6210\u4e00\u4e2a<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">__attribute__((constructor))<\/code>\u7684\u51fd\u6570\uff0c\u5728\u8be5\u51fd\u6570\u4e2d\u5c06\u53c2\u6570\u4f20\u5165\u7684\u51fd\u6570\u52a0\u5165\u5230\u4e00\u4e2a\u94fe\u8868\u4e2d\uff0c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">__attribute__((constructor))<\/code>\u5c5e\u6027\u53ef\u4ee5\u4fdd\u8bc1\u751f\u6210\u7684\u51fd\u6570\u4f1a\u5728<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">main<\/code>\u4e4b\u524d\u88ab\u8c03\u7528\uff09\u3002\u5728<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">main<\/code>\u51fd\u6570\u4e2d\u901a\u8fc7<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">module_call_init(MODULE_INIT_QOM)<\/code>\u8c03\u7528\u901a\u8fc7<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_init<\/code>\u6ce8\u518c\u7684\u51fd\u6570\uff0c\u4e5f\u5c31\u662f\u5b9e\u73b0\u4e86\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeInfo<\/code>\u6ce8\u518c<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\u3002<\/p>\r\n<h2>\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\u6784\u9020\u7c7b\u5bf9\u8c61<\/h2>\r\n<p>\u4e2a\u4eba\u7406\u89e3\uff0c\u7c7b\u5bf9\u8c61\u5c31\u662f\u4e00\u4e2a\u5b58\u653e\u8be5\u7c7b\u7684\u5b9e\u4f8b\u5171\u7528\u7684\u4fe1\u606f\u7684\u7ed3\u6784\uff0c\u6bd4\u5982callback\uff08\u8fd9\u4e2a\u529f\u80fd\u7c7b\u4f3cC++\u4e2d\u7684\u865a\u51fd\u6570\u8868\uff09\u3001\u5c5e\u6027\u3002\u56e0\u6b64\u4e00\u4e2a\u7c7b\u53ea\u9700\u8981\u4e00\u4e2a\u7c7b\u5bf9\u8c61\uff0c\u8be5\u7c7b\u7684\u6240\u6709\u5b9e\u4f8b\u5171\u7528\u8fd9\u4e00\u4e2a\u7c7b\u5bf9\u8c61\u3002\u5728\u8be5\u7c7b\u5b9e\u4f8b\u5316\u7b2c\u4e00\u4e2a\u5b9e\u4f8b\u5bf9\u8c61\u65f6\uff0c\u4f1a\u9996\u5148\u901a\u8fc7<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">type_initialize<\/code>\u5b9e\u4f8b\u5316\u7c7b\u5bf9\u8c61\uff0c\u5e76\u5c06<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">TypeImpl<\/code>\u4e2d\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">class<\/code>\u6307\u5411\u8be5\u7c7b\u5bf9\u8c61\u3002<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">static void type_initialize(TypeImpl *ti)\r\n{\r\n    TypeImpl *parent;\r\n\r\n    \/\/ \u5982\u679c\u5df2\u7ecf\u8be5\u7c7b\u7684\u7c7b\u5bf9\u8c61\u5df2\u7ecf\u521d\u59cb\u5316\u4e86\uff0c\u5219\u76f4\u63a5\u8fd4\u56de\r\n    if (ti-&gt;class) {\r\n        return;\r\n    }\r\n\r\n    ti-&gt;class_size = type_class_get_size(ti);\r\n    ti-&gt;instance_size = type_object_get_size(ti);\r\n    \/* Any type with zero instance_size is implicitly abstract.\r\n     * This means interface types are all abstract.\r\n     *\/\r\n    if (ti-&gt;instance_size == 0) {\r\n        ti-&gt;abstract = true;\r\n    }\r\n    if (type_is_ancestor(ti, type_interface)) {\r\n        ...\r\n    }\r\n    ti-&gt;class = g_malloc0(ti-&gt;class_size);\r\n\r\n    parent = type_get_parent(ti);\r\n    if (parent) {\r\n        \/\/ \u5982\u679c\u8be5\u7c7b\u5b58\u5728\u7236\u7c7b\uff0c\u5219\u9996\u5148\u521d\u59cb\u5316\u7236\u7c7b\u7684\u7c7b\u5bf9\u8c61\uff0c\u518d\u5c06\u7236\u7c7b\u7684\u7c7b\u5bf9\u8c61\u62f7\u8d1d\u8fc7\u6765\r\n        type_initialize(parent);\r\n        ...\r\n        memcpy(ti-&gt;class, parent-&gt;class, parent-&gt;class_size);\r\n        ...\r\n    } else {\r\n        ti-&gt;class-&gt;properties = g_hash_table_new_full(\r\n            g_str_hash, g_str_equal, g_free, object_property_free);\r\n    }\r\n\r\n    ti-&gt;class-&gt;type = ti;\r\n    \/\/ \u4e0a\u8ff0\u62f7\u8d1d\u7236\u7c7b\u7c7b\u5bf9\u8c61\u65f6\u5982\u679c\u5b58\u5728\u526f\u4f5c\u7528\uff0c\u5219\u901a\u8fc7class_base_init\u6d88\u9664\r\n    while (parent) {\r\n        if (parent-&gt;class_base_init) {\r\n            parent-&gt;class_base_init(ti-&gt;class, ti-&gt;class_data);\r\n        }\r\n        parent = type_get_parent(parent);\r\n    }\r\n    \/\/ \u8c03\u7528class_init\u521d\u59cb\u5316\u7c7b\u5bf9\u8c61\uff1b\u7531\u4e8e\u4e0a\u8ff0\u5df2\u7ecf\u5b9e\u4f8b\u5316\u7236\u7c7b\u7684\u7c7b\u5bf9\u8c61\u4e86\uff0c\u56e0\u6b64class_init\u7684\u8c03\u7528\u987a\u5e8f\u662f\u5148\u8c03\u7528\u7236\u7c7b\u7684class_init\uff0c\u518d\u8c03\u7528\u5b50\u7c7b\u7684class_init\r\n    if (ti-&gt;class_init) {\r\n        ti-&gt;class_init(ti-&gt;class, ti-&gt;class_data);\r\n    }\r\n}<\/pre>\r\n<h2>\u6839\u636e<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\u6784\u9020\u5bf9\u8c61<\/h2>\r\n<p>\u5f53\u6784\u9020\u5bf9\u8c61\u65f6\uff0c\u9996\u5148\u6839\u636e\u7c7b\u578b\u540d\u67e5\u627e\u5230\u5bf9\u5e94\u7684<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">TypeImpl<\/code>\uff0c\u5206\u914d\u4e00\u6bb5\u5bf9\u5e94\u5927\u5c0f\uff08\u5927\u5c0f\u4e3a<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">type-&gt;instance_size<\/code>\uff09\u7684\u5185\u5b58\u540e\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_initialize_with_type<\/code>\u8fdb\u884c\u5bf9\u8c61\u7684\u521d\u59cb\u5316\u3002<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_initialize_with_type<\/code>\u9996\u5148\u4f1a\u5229\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">obj-&gt;calss = type-&gt;class<\/code>\u5c06\u5bf9\u8c61\u4e0e\u5176\u5bf9\u5e94\u7684\u7c7b\u5bf9\u8c61\u5173\u8054\u8d77\u6765\uff0c\u7136\u540e\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_init_with_type<\/code>\u6765\u4f9d\u6b21\u8c03\u7528\u6784\u9020\u51fd\u6570\uff08<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">instance_init<\/code>\uff09\u6765\u5b8c\u6210\u521d\u59cb\u5316\u3002<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"generic\">static void object_initialize_with_type(void *data, size_t size, TypeImpl *type)\r\n{\r\n    Object *obj = data;\r\n\r\n    ...\r\n    memset(obj, 0, type-&gt;instance_size);\r\n    obj-&gt;class = type-&gt;class;\r\n    object_ref(obj);\r\n    ...\r\n    object_init_with_type(obj, type);\r\n    object_post_init_with_type(obj, type);\r\n}\r\n\r\nstatic void object_init_with_type(Object *obj, TypeImpl *ti)\r\n{\r\n    \/\/ \u5148\u8c03\u7528\u7236\u7c7b\u7684\u6784\u9020\u51fd\u6570\r\n    if (type_has_parent(ti)) {\r\n        object_init_with_type(obj, type_get_parent(ti));\r\n    }\r\n\r\n    \/\/ \u518d\u8c03\u7528\u5b50\u7c7b\u7684\u6784\u9020\u51fd\u6570\r\n    if (ti-&gt;instance_init) {\r\n        ti-&gt;instance_init(obj);\r\n    }\r\n}<\/pre>\r\n<h1>\u6790\u6784<\/h1>\r\n<hr \/>\r\n<p>QOM\u7684\u5bf9\u8c61\u5728\u6784\u9020\u51fa\u6765\u4e4b\u540e\u9700\u8981\u4f9d\u8d56\u5f15\u7528\u8ba1\u6570\u6765\u8fdb\u884c\u5185\u5b58\u7684\u7ba1\u7406\uff0c\u8fd9\u9700\u8981\u5f00\u53d1\u8005\u624b\u52a8\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_ref<\/code>\/<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_unref<\/code>\uff0c\u5f53\u5f15\u7528\u8ba1\u6570\u8fbe\u52300\u65f6\uff0c\u5219\u4f1a\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">object_finalize<\/code>\u8fdb\u884c\u5bf9\u8c61\u7684\u6790\u6784\uff0c\u6790\u6784\u65f6\u9996\u5148\u4f1a\u8c03\u7528\u5b50\u7c7b\u7684\u6790\u6784\u51fd\u6570\uff0c\u518d\u8c03\u7528\u7236\u7c7b\u7684\u6790\u6784\u51fd\u6570\uff0c\u6700\u540e\u8c03\u7528<code class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">free<\/code>\u91ca\u653e\u8be5\u5bf9\u8c61\u7684\u5185\u5b58\u3002<\/p>\r\n<pre class=\"EnlighterJSRAW\" data-enlighter-language=\"c\">static void object_deinit(Object *obj, TypeImpl *type)\r\n{\r\n    \/\/ \u5148\u8c03\u7528\u5b50\u7c7b\u7684\u6790\u6784\u51fd\u6570\r\n    if (type-&gt;instance_finalize) {\r\n        type-&gt;instance_finalize(obj);\r\n    }\r\n\r\n    \/\/ \u518d\u8c03\u7528\u7236\u7c7b\u7684\u6790\u6784\u51fd\u6570\r\n    if (type_has_parent(type)) {\r\n        object_deinit(obj, type_get_parent(type));\r\n    }\r\n}\r\n\r\nstatic void object_finalize(void *data)\r\n{\r\n    Object *obj = data;\r\n    TypeImpl *ti = obj-&gt;class-&gt;type;\r\n\r\n    object_property_del_all(obj);\r\n    object_deinit(obj, ti);\r\n\r\n    g_assert(obj-&gt;ref == 0);\r\n    if (obj-&gt;free) {\r\n        obj-&gt;free(obj);\r\n    }\r\n}<\/pre>\r\n<h1>\u53c2\u8003\u8d44\u6599<\/h1>\r\n<hr \/>\r\n<ol>\r\n<li><a href=\"https:\/\/www.binss.me\/blog\/qemu-note-of-qemu-object-model\/\" target=\"_blank\" rel=\"noopener noreferrer\">QEMU\u5b66\u4e60\u7b14\u8bb0\u2014\u2014QOM(Qemu Object Model)<\/a><\/li>\r\n<li><a href=\"https:\/\/juniorprincewang.github.io\/2018\/07\/23\/qemu%E6%BA%90%E7%A0%81%E6%B7%BB%E5%8A%A0%E8%AE%BE%E5%A4%87\/\" target=\"_blank\" rel=\"noopener noreferrer\">QEMU\u8bbe\u5907\u7684\u5bf9\u8c61\u6a21\u578bQOM<\/a><\/li>\r\n<\/ol>\r\n","protected":false},"excerpt":{"rendered":"<p>\u672c\u6587\u57fa\u4e8eQEMU 7.0\u3002 QEMU\u4e2d\u540c\u4e00\u7c7b\u522b\u7684\u8bbe\u5907\u53ef\u80fd\u6709\u5f88\u591a\u79cd\uff0c\u5bf9\u4e8e\u540c\u7c7b\u4e0d\u540c\u79cd\u7684\u8bbe\u5907\uff0c\u9700\u8981\u8c03\u7528\u4e0d\u540c\u7684\u51fd\u6570\u8fdb\u884c [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21,20],"tags":[22,4,23],"class_list":["post-145","post","type-post","status-publish","format-standard","hentry","category-qemu","category-virtualization","tag-qemu","tag-virtualization","tag-23"],"_links":{"self":[{"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=\/wp\/v2\/posts\/145","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=145"}],"version-history":[{"count":1,"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=\/wp\/v2\/posts\/145\/revisions"}],"predecessor-version":[{"id":423,"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=\/wp\/v2\/posts\/145\/revisions\/423"}],"wp:attachment":[{"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=145"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=145"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.tcx4c70.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=145"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}