# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1715569983 -10800
# Node ID 6a3ee145d0b549a9b6f4e8a4abe81ef6f8c101df
# Parent  9a5e2296c1be7c379fa6162cde61721c64e22349
Core: made it possible to disable PID files with "pid off".

While it is not generally recommended, this might be beneficial in some
configurations, such as with immutable images and direct control by
a service manager.

diff --git a/src/core/nginx.c b/src/core/nginx.c
--- a/src/core/nginx.c
+++ b/src/core/nginx.c
@@ -766,7 +766,9 @@ ngx_exec_new_binary(ngx_cycle_t *cycle, 
 
     ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
 
-    if (ngx_rename_file(ccf->pid.data, ccf->oldpid.data) == NGX_FILE_ERROR) {
+    if (ccf->pid.len
+        && ngx_rename_file(ccf->pid.data, ccf->oldpid.data) == NGX_FILE_ERROR)
+    {
         ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                       ngx_rename_file_n " %s to %s failed "
                       "before executing new binary process \"%s\"",
@@ -781,8 +783,9 @@ ngx_exec_new_binary(ngx_cycle_t *cycle, 
     pid = ngx_execute(cycle, &ctx);
 
     if (pid == NGX_INVALID_PID) {
-        if (ngx_rename_file(ccf->oldpid.data, ccf->pid.data)
-            == NGX_FILE_ERROR)
+        if (ccf->pid.len
+            && ngx_rename_file(ccf->oldpid.data, ccf->pid.data)
+               == NGX_FILE_ERROR)
         {
             ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                           ngx_rename_file_n " %s back to %s failed after "
@@ -1168,20 +1171,26 @@ ngx_core_module_init_conf(ngx_cycle_t *c
         ngx_str_set(&ccf->pid, NGX_PID_PATH);
     }
 
-    if (ngx_conf_full_name(cycle, &ccf->pid, 0) != NGX_OK) {
-        return NGX_CONF_ERROR;
-    }
+    if (ngx_strcmp(ccf->pid.data, "off") == 0) {
+        ngx_str_set(&ccf->pid, "");
+        ngx_str_set(&ccf->oldpid, "");
 
-    ccf->oldpid.len = ccf->pid.len + sizeof(NGX_OLDPID_EXT);
+    } else {
+        if (ngx_conf_full_name(cycle, &ccf->pid, 0) != NGX_OK) {
+            return NGX_CONF_ERROR;
+        }
 
-    ccf->oldpid.data = ngx_pnalloc(cycle->pool, ccf->oldpid.len);
-    if (ccf->oldpid.data == NULL) {
-        return NGX_CONF_ERROR;
+        ccf->oldpid.len = ccf->pid.len + sizeof(NGX_OLDPID_EXT);
+
+        ccf->oldpid.data = ngx_pnalloc(cycle->pool, ccf->oldpid.len);
+        if (ccf->oldpid.data == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        ngx_memcpy(ngx_cpymem(ccf->oldpid.data, ccf->pid.data, ccf->pid.len),
+                   NGX_OLDPID_EXT, sizeof(NGX_OLDPID_EXT));
     }
 
-    ngx_memcpy(ngx_cpymem(ccf->oldpid.data, ccf->pid.data, ccf->pid.len),
-               NGX_OLDPID_EXT, sizeof(NGX_OLDPID_EXT));
-
 
 #if !(NGX_WIN32)
 
diff --git a/src/core/ngx_cycle.c b/src/core/ngx_cycle.c
--- a/src/core/ngx_cycle.c
+++ b/src/core/ngx_cycle.c
@@ -1027,6 +1027,10 @@ ngx_create_pidfile(ngx_str_t *name, ngx_
         return NGX_OK;
     }
 
+    if (name->len == 0) {
+        return NGX_OK;
+    }
+
     ngx_memzero(&file, sizeof(ngx_file_t));
 
     file.name = *name;
@@ -1070,6 +1074,10 @@ ngx_delete_pidfile(ngx_cycle_t *cycle)
 
     ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
 
+    if (ccf->pid.len == 0) {
+        return;
+    }
+
     name = ngx_new_binary ? ccf->oldpid.data : ccf->pid.data;
 
     if (ngx_delete_file(name) == NGX_FILE_ERROR) {
@@ -1092,6 +1100,12 @@ ngx_signal_process(ngx_cycle_t *cycle, c
 
     ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);
 
+    if (ccf->pid.len == 0) {
+        ngx_log_error(NGX_LOG_ERR, cycle->log, 0,
+                      "no PID file configured");
+        return 1;
+    }
+
     ngx_memzero(&file, sizeof(ngx_file_t));
 
     file.name = ccf->pid;
diff --git a/src/os/unix/ngx_process_cycle.c b/src/os/unix/ngx_process_cycle.c
--- a/src/os/unix/ngx_process_cycle.c
+++ b/src/os/unix/ngx_process_cycle.c
@@ -619,9 +619,10 @@ ngx_reap_children(ngx_cycle_t *cycle)
                 ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                        ngx_core_module);
 
-                if (ngx_rename_file((char *) ccf->oldpid.data,
-                                    (char *) ccf->pid.data)
-                    == NGX_FILE_ERROR)
+                if (ccf->pid.len
+                    && ngx_rename_file((char *) ccf->oldpid.data,
+                                       (char *) ccf->pid.data)
+                       == NGX_FILE_ERROR)
                 {
                     ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                                   ngx_rename_file_n " %s back to %s failed "