nginx中ngx_cycle_s的conf_ctx初始化
ngx_cycle_t
是结构体ngx_cycle_s的别名
typedef struct ngx_cycle_s ngx_cycle_t;结构体ngx_cycle_s的定义
struct ngx_cycle_s {void ****conf_ctx;ngx_pool_t *pool;ngx_log_t *log;ngx_log_t new_log;ngx_uint_t log_use_stderr; /* unsigned log_use_stderr:1; */ngx_connection_t **files;ngx_connection_t *free_connections;ngx_uint_t free_connection_n;ngx_module_t **modules;ngx_uint_t modules_n;ngx_uint_t modules_used; /* unsigned modules_used:1; */ngx_queue_t reusable_connections_queue;ngx_uint_t reusable_connections_n;time_t connections_reuse_time;ngx_array_t listening;ngx_array_t paths;ngx_array_t config_dump;ngx_rbtree_t config_dump_rbtree;ngx_rbtree_node_t config_dump_sentinel;ngx_list_t open_files;ngx_list_t shared_memory;ngx_uint_t connection_n;ngx_uint_t files_n;ngx_connection_t *connections;ngx_event_t *read_events;ngx_event_t *write_events;ngx_cycle_t *old_cycle;ngx_str_t conf_file;ngx_str_t conf_param;ngx_str_t conf_prefix;ngx_str_t prefix;ngx_str_t error_log;ngx_str_t lock_file;ngx_str_t hostname;
};conf_ctx
创建
在ngx_init_cycle中创建conf_ctx，分配内存。创建ngx_max_module个void* 内存块
cycle->conf_ctx = ngx_pcalloc(pool, ngx_max_module * sizeof(void *));if (cycle->conf_ctx == NULL) {ngx_destroy_pool(pool);return NULL;}第一次赋值
模块类型为CORE_MODULE，调用核心模块的create_conf方法来分配内存
for (i = 0; cycle->modules[i]; i++) {if (cycle->modules[i]->type != NGX_CORE_MODULE) {continue;}module = cycle->modules[i]->ctx;if (module->create_conf) {rv = module->create_conf(cycle);if (rv == NULL) {ngx_destroy_pool(pool);return NULL;}cycle->conf_ctx[cycle->modules[i]->index] = rv;}}核心模块中有create_conf的模块有
模块 | create_conf方法 |
ngx_core_module | ngx_core_module_create_conf |
ngx_openssl_module | ngx_openssl_create_conf |
ngx_google_perftools_module | ngx_google_perftools_create_conf |
ngx_regex_module | ngx_regex_create_conf |
ngx_thread_pool_module | ngx_thread_pool_create_conf |
解析模块类型为CORE_MODULE且命令类型为NGX_MAIN_CONF
模块 | 命令名 | 命令处理 |
ngx_core_module | daemon | ngx_conf_set_flag_slot |
master_process | ngx_conf_set_flag_slot | |
timer_resolution | ngx_conf_set_msec_slot | |
pid | ngx_conf_set_str_slot | |
lock_file | ngx_conf_set_str_slot | |
worker_processes | ngx_set_worker_processes | |
debug_points | ngx_conf_set_enum_slot | |
user | ngx_set_user | |
worker_priority | ngx_set_priority | |
worker_cpu_affinity | ngx_set_cpu_affinity | |
worker_rlimit_nofile | ngx_conf_set_num_slot | |
worker_rlimit_core | ngx_conf_set_off_slot | |
worker_shutdown_timeout | ngx_conf_set_msec_slot | |
working_directory | ngx_conf_set_str_slot | |
env | ngx_set_env | |
load_module | ngx_load_module | |
ngx_events_module | events | ngx_events_block |
ngx_openssl_module | ssl_engine | ngx_openssl_engine |
ngx_google_perftools_module | google_perftools_profiles | ngx_conf_set_str_slot |
ngx_http_module | http | ngx_http_block |
ngx_errlog_module | error_log | ngx_error_log |
ngx_mail_module | ngx_mail_block | |
ngx_regex_module | pcre_jit | ngx_conf_set_flag_slot |
ngx_stream_module | stream | ngx_stream_block |
ngx_thread_pool_module | thread_pool | ngx_thread_pool |
第二次赋值
是在ngx_conf_handler中的判断命令类型是否是NGX_MAIN_CONF，此时(((void **) cf->ctx)[cf->cycle->modules[i]->index])是对应模块的配置信息的地址，其存的值是NULL。
通过命令接口的set方法来设置conf
ngx_conf_handler
if (cmd->type & NGX_DIRECT_CONF) {conf = ((void **) cf->ctx)[cf->cycle->modules[i]->index];} else if (cmd->type & NGX_MAIN_CONF) {conf = &(((void **) cf->ctx)[cf->cycle->modules[i]->index]);} else if (cf->ctx) {confp = *(void **) ((char *) cf->ctx + cmd->conf);if (confp) {conf = confp[cf->cycle->modules[i]->ctx_index];}}rv = cmd->set(cf, cmd, conf);根据命令类型是否是NGX_DIRECT_CONF还是NGX_MAIN_CONF，模块中有命令类型是NGX_DIRECT_CONF则其子接口中都有create_conf方法。
ngx_core_module核心模块中的命令都是NGX_DIRECT_CONF类型