# HG changeset patch
# User Igor Sysoev <igor@sysoev.ru>
# Date 1169406061 0
# Node ID bd4202f92581d25bd2b683cabe594d49f98b0946
# Parent  b54a1e283d6d0626c643bce5f4cc1c15f3d57346
log a failure of the writing to access_log once per minute

diff --git a/src/http/modules/ngx_http_log_module.c b/src/http/modules/ngx_http_log_module.c
--- a/src/http/modules/ngx_http_log_module.c
+++ b/src/http/modules/ngx_http_log_module.c
@@ -42,6 +42,7 @@ typedef struct {
 typedef struct {
     ngx_open_file_t            *file;
     time_t                      disk_full_time;
+    time_t                      error_log_time;
     ngx_array_t                *ops;        /* array of ngx_http_log_op_t */
 } ngx_http_log_t;
 
@@ -59,6 +60,9 @@ typedef struct {
 } ngx_http_log_var_t;
 
 
+static void ngx_http_log_write(ngx_http_request_t *r, ngx_http_log_t *log,
+    u_char *buf, size_t len);
+
 static u_char *ngx_http_log_connection(ngx_http_request_t *r, u_char *buf,
     ngx_http_log_op_t *op);
 static u_char *ngx_http_log_pipe(ngx_http_request_t *r, u_char *buf,
@@ -183,9 +187,9 @@ static ngx_http_log_var_t  ngx_http_log_
 ngx_int_t
 ngx_http_log_handler(ngx_http_request_t *r)
 {
-    ngx_uint_t                i, l;
     u_char                   *line, *p;
     size_t                    len;
+    ngx_uint_t                i, l;
     ngx_http_log_t           *log;
     ngx_open_file_t          *file;
     ngx_http_log_op_t        *op;
@@ -206,9 +210,9 @@ ngx_http_log_handler(ngx_http_request_t 
         if (ngx_time() == log[l].disk_full_time) {
 
             /*
-             * On FreeBSD writing to a full filesystem with enabled softupdates
+             * on FreeBSD writing to a full filesystem with enabled softupdates
              * may block process for much longer time than writing to non-full
-             * filesystem, so we skip writing the log for one second.
+             * filesystem, so we skip writing to a log for one second
              */
 
             continue;
@@ -233,13 +237,8 @@ ngx_http_log_handler(ngx_http_request_t 
 
             if (len > (size_t) (file->last - file->pos)) {
 
-                if (ngx_write_fd(file->fd, file->buffer,
-                                 file->pos - file->buffer)
-                    == -1
-                    && ngx_errno == NGX_ENOSPC)
-                {
-                    log[l].disk_full_time = ngx_time();
-                }
+                ngx_http_log_write(r, &log[l], file->buffer,
+                                   file->pos - file->buffer);
 
                 file->pos = file->buffer;
             }
@@ -273,17 +272,57 @@ ngx_http_log_handler(ngx_http_request_t 
 
         ngx_linefeed(p);
 
-        if (ngx_write_fd(file->fd, line, p - line) == -1
-            && ngx_errno == NGX_ENOSPC)
-        {
-            log[l].disk_full_time = ngx_time();
-        }
+        ngx_http_log_write(r, &log[l], line, p - line);
     }
 
     return NGX_OK;
 }
 
 
+static void
+ngx_http_log_write(ngx_http_request_t *r, ngx_http_log_t *log, u_char *buf,
+    size_t len)
+{
+    time_t     now;
+    ssize_t    n;
+    ngx_err_t  err;
+
+    n = ngx_write_fd(log->file->fd, buf, len);
+
+    if (n == (ssize_t) len) {
+        return;
+    }
+
+    now = ngx_time();
+
+    if (n == -1) {
+        err = ngx_errno;
+
+        if (err == NGX_ENOSPC) {
+            log->disk_full_time = now;
+        }
+
+        if (now - log->error_log_time > 60) {
+            ngx_log_error(NGX_LOG_ALERT, r->connection->log, err,
+                          ngx_write_fd_n " to \"%V\" failed",
+                          &log->file->name);
+
+            log->error_log_time = now;
+        }
+
+        return;
+    }
+
+    if (now - log->error_log_time > 60) {
+        ngx_log_error(NGX_LOG_ALERT, r->connection->log, 0,
+                      ngx_write_fd_n " to \"%V\" was incomplete: %z of %uz",
+                      &log->file->name, n, len);
+
+        log->error_log_time = now;
+    }
+}
+
+
 static u_char *
 ngx_http_log_copy_short(ngx_http_request_t *r, u_char *buf,
     ngx_http_log_op_t *op)
@@ -547,6 +586,7 @@ ngx_http_log_merge_loc_conf(ngx_conf_t *
             }
 
             log->disk_full_time = 0;
+            log->error_log_time = 0;
 
             lmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_log_module);
             fmt = lmcf->formats.elts;
@@ -600,6 +640,7 @@ ngx_http_log_set_log(ngx_conf_t *cf, ngx
     }
 
     log->disk_full_time = 0;
+    log->error_log_time = 0;
 
     if (cf->args->nelts >= 3) {
         name = value[2];