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Posted on 2014-11-05 17:44 S.l.e!ep.￠% 閱讀(710) 評論(0) 編輯 收藏 引用 所屬分類: Skynet
bootstrap(..); 之前的代碼沒看懂
bootstrap()代碼如下
static?void
bootstrap(struct?skynet_context?*?logger,?const?char?*?cmdline)?{
????int?sz?=?strlen(cmdline);
????char?name[sz+1];
????char?args[sz+1];
????sscanf(cmdline,?"%s?%s",?name,?args);
????struct?skynet_context?*ctx?=?skynet_context_new(name,?args);
????if?(ctx?==?NULL)?{
????????skynet_error(NULL,?"Bootstrap?error?:?%s\n",?cmdline);
????????skynet_context_dispatchall(logger);
????????exit(1);
????}
}
一開始以為 skynet_context_new() 只是malloc()之類的調用而已 后來再看看 skynet_context_new() 的源碼
struct?skynet_context?*?
skynet_context_new(const?char?*?name,?const?char?*param)?{
????struct?skynet_module?*?mod?=?skynet_module_query(name);
????if?(mod?==?NULL)
????????return?NULL;
????void?*inst?=?skynet_module_instance_create(mod);
????if?(inst?==?NULL)
????????return?NULL;
????struct?skynet_context?*?ctx?=?skynet_malloc(sizeof(*ctx));
????CHECKCALLING_INIT(ctx)
????ctx->mod?=?mod;
????ctx->instance?=?inst;
????ctx->ref?=?2;
????ctx->cb?=?NULL;
????ctx->cb_ud?=?NULL;
????ctx->session_id?=?0;
????ctx->logfile?=?NULL;
????ctx->init?=?false;
????ctx->endless?=?false;
????//?Should?set?to?0?first?to?avoid?skynet_handle_retireall?get?an?uninitialized?handle
????ctx->handle?=?0;????
????ctx->handle?=?skynet_handle_register(ctx);
????struct?message_queue?*?queue?=?ctx->queue?=?skynet_mq_create(ctx->handle);
????//?init?function?maybe?use?ctx->handle,?so?it?must?init?at?last
????context_inc();
????CHECKCALLING_BEGIN(ctx)
????int?r?=?skynet_module_instance_init(mod,?inst,?ctx,?param);
????CHECKCALLING_END(ctx)
????if?(r?==?0)?{
????????struct?skynet_context?*?ret?=?skynet_context_release(ctx);
????????if?(ret)?{
????????????ctx->init?=?true;
????????}
????????skynet_globalmq_push(queue);
????????if?(ret)?{
????????????skynet_error(ret,?"LAUNCH?%s?%s",?name,?param???param?:?"");
????????}
????????return?ret;
????}?else?{
????????skynet_error(ctx,?"FAILED?launch?%s",?name);
????????uint32_t?handle?=?ctx->handle;
????????skynet_context_release(ctx);
????????skynet_handle_retire(handle);
????????struct?drop_t?d?=?{?handle?};
????????skynet_mq_release(queue,?drop_message,?&d);
????????return?NULL;
????}
}
大概是進行了模塊的初始化，并為這個模塊創建消息隊列, 并放到全局的隊列里(注:模塊初始化時會將 param 傳進去)
之后開啟線程,進行消息處理
_start(config->thread);
用GDB調試,看下堆棧
#0??_init?(l=0x2b98570163a0,?ctx=0x2b98570540f0,?args=0x2b9857099070?"bootstrap",?sz=9)?at?service-src/service_snlua.c:71
#1??0x00002b9857d02469?in?_launch?(context=0x2b98570540f0,?ud=0x2b98570163a0,?type=0,?session=0,?source=16777218,?msg=0x2b9857099070,?sz=9)?at?service-src/service_snlua.c:125
#2??0x0000000000409546?in?dispatch_message?(ctx=0x2b98570540f0,?msg=0x420030e0)?at?skynet-src/skynet_server.c:254
#3??0x00000000004096c4?in?skynet_context_message_dispatch?(sm=0x2b9857016440,?q=0x2b98570530c0,?weight=-1)?at?skynet-src/skynet_server.c:308
#4??0x000000000040a98f?in?_worker?(p=0x7fff54a5f8d0)?at?skynet-src/skynet_start.c:128
為何會調用到 _launch? 回到前面
static?void
bootstrap(struct?skynet_context?*?logger,?const?char?*?cmdline)?{
????int?sz?=?strlen(cmdline);
????char?name[sz+1];
????char?args[sz+1];
????sscanf(cmdline,?"%s?%s",?name,?args);
????struct?skynet_context?*ctx?=?skynet_context_new(name,?args);?// 這里傳的參數分別為 snlua?bootstrap
????if?(ctx?==?NULL)?{
????????skynet_error(NULL,?"Bootstrap?error?:?%s\n",?cmdline);
????????skynet_context_dispatchall(logger);
????????exit(1);
????}
}
調用的流程是這樣的
#0? _open_sym (mod=0x2b9e0a032438) at skynet-src/skynet_module.c:76
#1? 0x0000000000408463 in skynet_module_query (name=0x7fffa16ae600 "snlua") at skynet-src/skynet_module.c:107
#2? 0x0000000000409099 in skynet_context_new (name=0x7fffa16ae600 "snlua", param=0x7fffa16ae5e0 "bootstrap") at skynet-src/skynet_server.c:117
#3? 0x000000000040adda in bootstrap (logger=0x2b9e0a054080, cmdline=0x2b9e0a0aa298 "snlua bootstrap") at skynet-src/skynet_start.c:204
#4? 0x000000000040aedb in skynet_start (config=0x7fffa16ae6d0) at skynet-src/skynet_start.c:232
#5? 0x000000000040751e in main (argc=2, argv=0x7fffa16ae7f8) at skynet-src/skynet_main.c:139
skynet_context_new 會先去 cservice目錄下 查找 snlua.so , 然后分別找
snlua_create? --->? skynet_module->create
snlua_init??? --->? skynet_module->init
snlua_release --->? skynet_module->release
這三個函數然后分別賦值給 skynet_module 的 create / init / release
snlua.so 的代碼在 service_snlua.c
看 snlua_init() 函數代碼就知道它將 skynet_context 的 cb 賦值為 _launch
int
snlua_init(struct?snlua?*l,?struct?skynet_context?*ctx,?const?char?*?args)?{
????int?sz?=?strlen(args);
????char?*?tmp?=?skynet_malloc(sz);
????memcpy(tmp,?args,?sz);
????skynet_callback(ctx,?l?,?_launch);? // 這句代碼將 skynet_context 的 cb 賦值為 _launch
??? const?char?*?self?=?skynet_command(ctx,?"REG",?NULL);
????uint32_t?handle_id?=?strtoul(self+1,?NULL,?16);
????//?it?must?be?first?message
????skynet_send(ctx,?0,?handle_id,?PTYPE_TAG_DONTCOPY,0,?tmp,?sz);
????return?0;
}
再看回下面的消息分派 dispatch_message() 里有以下代碼, 實際上就是調用了 _launch()
??? if (!ctx->cb(ctx, ctx->cb_ud, type, msg->session, msg->source, msg->data, sz)) {
??? ??? skynet_free(msg->data);
??? }
#0??_init?(l=0x2b98570163a0,?ctx=0x2b98570540f0,?args=0x2b9857099070?"bootstrap",?sz=9)?at?service-src/service_snlua.c:71
#1??0x00002b9857d02469?in?_launch?(context=0x2b98570540f0,?ud=0x2b98570163a0,?type=0,?session=0,?source=16777218,?msg=0x2b9857099070,?sz=9)?at?service-src/service_snlua.c:125
#2??0x0000000000409546?in?dispatch_message?(ctx=0x2b98570540f0,?msg=0x420030e0)?at?skynet-src/skynet_server.c:254
#3??0x00000000004096c4?in?skynet_context_message_dispatch?(sm=0x2b9857016440,?q=0x2b98570530c0,?weight=-1)?at?skynet-src/skynet_server.c:308
#4??0x000000000040a98f?in?_worker?(p=0x7fff54a5f8d0)?at?skynet-src/skynet_start.c:128
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