Mercurial > hg > nginx
view src/stream/ngx_stream_upstream_zone_module.c @ 9270:3d455e37abf8
Core: PID file writing synchronization.
Now, ngx_daemon() does not call exit() in the parent process immediately,
but instead waits for the child process to signal it actually started (and
wrote the PID file if configured to). This ensures that the PID file
already exists when the parent process exits.
To make sure that signal handlers won't cause unexpected logging in the
parent process if the child process dies (for example, due to errors when
writing the PID file), ngx_init_signals() is moved to the child process.
This resolves "PID file ... not readable (yet?) after start" and "Failed
to parse PID from file..." errors as observed with systemd.
Note that the errors observed are considered to be a bug in systemd, which
isn't able to work properly with traditional Unix daemons. Still, the
workaround is implemented to make sure there will be no OS vendor patches
trying to address this.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 13 May 2024 06:13:22 +0300 |
parents | 3b1b81e248bc |
children |
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/* * Copyright (C) Ruslan Ermilov * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> static char *ngx_stream_upstream_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf); static ngx_int_t ngx_stream_upstream_init_zone(ngx_shm_zone_t *shm_zone, void *data); static ngx_stream_upstream_rr_peers_t *ngx_stream_upstream_zone_copy_peers( ngx_slab_pool_t *shpool, ngx_stream_upstream_srv_conf_t *uscf); static ngx_stream_upstream_rr_peer_t *ngx_stream_upstream_zone_copy_peer( ngx_stream_upstream_rr_peers_t *peers, ngx_stream_upstream_rr_peer_t *src); static ngx_command_t ngx_stream_upstream_zone_commands[] = { { ngx_string("zone"), NGX_STREAM_UPS_CONF|NGX_CONF_TAKE12, ngx_stream_upstream_zone, 0, 0, NULL }, ngx_null_command }; static ngx_stream_module_t ngx_stream_upstream_zone_module_ctx = { NULL, /* preconfiguration */ NULL, /* postconfiguration */ NULL, /* create main configuration */ NULL, /* init main configuration */ NULL, /* create server configuration */ NULL /* merge server configuration */ }; ngx_module_t ngx_stream_upstream_zone_module = { NGX_MODULE_V1, &ngx_stream_upstream_zone_module_ctx, /* module context */ ngx_stream_upstream_zone_commands, /* module directives */ NGX_STREAM_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static char * ngx_stream_upstream_zone(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { ssize_t size; ngx_str_t *value; ngx_stream_upstream_srv_conf_t *uscf; ngx_stream_upstream_main_conf_t *umcf; uscf = ngx_stream_conf_get_module_srv_conf(cf, ngx_stream_upstream_module); umcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_upstream_module); value = cf->args->elts; if (!value[1].len) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid zone name \"%V\"", &value[1]); return NGX_CONF_ERROR; } if (cf->args->nelts == 3) { size = ngx_parse_size(&value[2]); if (size == NGX_ERROR) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid zone size \"%V\"", &value[2]); return NGX_CONF_ERROR; } if (size < (ssize_t) (8 * ngx_pagesize)) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "zone \"%V\" is too small", &value[1]); return NGX_CONF_ERROR; } } else { size = 0; } uscf->shm_zone = ngx_shared_memory_add(cf, &value[1], size, &ngx_stream_upstream_module); if (uscf->shm_zone == NULL) { return NGX_CONF_ERROR; } uscf->shm_zone->init = ngx_stream_upstream_init_zone; uscf->shm_zone->data = umcf; uscf->shm_zone->noreuse = 1; return NGX_CONF_OK; } static ngx_int_t ngx_stream_upstream_init_zone(ngx_shm_zone_t *shm_zone, void *data) { size_t len; ngx_uint_t i; ngx_slab_pool_t *shpool; ngx_stream_upstream_rr_peers_t *peers, **peersp; ngx_stream_upstream_srv_conf_t *uscf, **uscfp; ngx_stream_upstream_main_conf_t *umcf; shpool = (ngx_slab_pool_t *) shm_zone->shm.addr; umcf = shm_zone->data; uscfp = umcf->upstreams.elts; if (shm_zone->shm.exists) { peers = shpool->data; for (i = 0; i < umcf->upstreams.nelts; i++) { uscf = uscfp[i]; if (uscf->shm_zone != shm_zone) { continue; } uscf->peer.data = peers; peers = peers->zone_next; } return NGX_OK; } len = sizeof(" in upstream zone \"\"") + shm_zone->shm.name.len; shpool->log_ctx = ngx_slab_alloc(shpool, len); if (shpool->log_ctx == NULL) { return NGX_ERROR; } ngx_sprintf(shpool->log_ctx, " in upstream zone \"%V\"%Z", &shm_zone->shm.name); /* copy peers to shared memory */ peersp = (ngx_stream_upstream_rr_peers_t **) (void *) &shpool->data; for (i = 0; i < umcf->upstreams.nelts; i++) { uscf = uscfp[i]; if (uscf->shm_zone != shm_zone) { continue; } peers = ngx_stream_upstream_zone_copy_peers(shpool, uscf); if (peers == NULL) { return NGX_ERROR; } *peersp = peers; peersp = &peers->zone_next; } return NGX_OK; } static ngx_stream_upstream_rr_peers_t * ngx_stream_upstream_zone_copy_peers(ngx_slab_pool_t *shpool, ngx_stream_upstream_srv_conf_t *uscf) { ngx_str_t *name; ngx_stream_upstream_rr_peer_t *peer, **peerp; ngx_stream_upstream_rr_peers_t *peers, *backup; peers = ngx_slab_alloc(shpool, sizeof(ngx_stream_upstream_rr_peers_t)); if (peers == NULL) { return NULL; } ngx_memcpy(peers, uscf->peer.data, sizeof(ngx_stream_upstream_rr_peers_t)); name = ngx_slab_alloc(shpool, sizeof(ngx_str_t)); if (name == NULL) { return NULL; } name->data = ngx_slab_alloc(shpool, peers->name->len); if (name->data == NULL) { return NULL; } ngx_memcpy(name->data, peers->name->data, peers->name->len); name->len = peers->name->len; peers->name = name; peers->shpool = shpool; for (peerp = &peers->peer; *peerp; peerp = &peer->next) { /* pool is unlocked */ peer = ngx_stream_upstream_zone_copy_peer(peers, *peerp); if (peer == NULL) { return NULL; } *peerp = peer; } if (peers->next == NULL) { goto done; } backup = ngx_slab_alloc(shpool, sizeof(ngx_stream_upstream_rr_peers_t)); if (backup == NULL) { return NULL; } ngx_memcpy(backup, peers->next, sizeof(ngx_stream_upstream_rr_peers_t)); backup->name = name; backup->shpool = shpool; for (peerp = &backup->peer; *peerp; peerp = &peer->next) { /* pool is unlocked */ peer = ngx_stream_upstream_zone_copy_peer(backup, *peerp); if (peer == NULL) { return NULL; } *peerp = peer; } peers->next = backup; done: uscf->peer.data = peers; return peers; } static ngx_stream_upstream_rr_peer_t * ngx_stream_upstream_zone_copy_peer(ngx_stream_upstream_rr_peers_t *peers, ngx_stream_upstream_rr_peer_t *src) { ngx_slab_pool_t *pool; ngx_stream_upstream_rr_peer_t *dst; pool = peers->shpool; dst = ngx_slab_calloc_locked(pool, sizeof(ngx_stream_upstream_rr_peer_t)); if (dst == NULL) { return NULL; } if (src) { ngx_memcpy(dst, src, sizeof(ngx_stream_upstream_rr_peer_t)); dst->sockaddr = NULL; dst->name.data = NULL; dst->server.data = NULL; } dst->sockaddr = ngx_slab_calloc_locked(pool, sizeof(ngx_sockaddr_t)); if (dst->sockaddr == NULL) { goto failed; } dst->name.data = ngx_slab_calloc_locked(pool, NGX_SOCKADDR_STRLEN); if (dst->name.data == NULL) { goto failed; } if (src) { ngx_memcpy(dst->sockaddr, src->sockaddr, src->socklen); ngx_memcpy(dst->name.data, src->name.data, src->name.len); dst->server.data = ngx_slab_alloc_locked(pool, src->server.len); if (dst->server.data == NULL) { goto failed; } ngx_memcpy(dst->server.data, src->server.data, src->server.len); } return dst; failed: if (dst->server.data) { ngx_slab_free_locked(pool, dst->server.data); } if (dst->name.data) { ngx_slab_free_locked(pool, dst->name.data); } if (dst->sockaddr) { ngx_slab_free_locked(pool, dst->sockaddr); } ngx_slab_free_locked(pool, dst); return NULL; }