server: Lookup user only once.

[paraslash.git] / stdin.c

diff --git a/stdin.c b/stdin.c
index b25a0ba013fb03b19cb757d07ff483c9389a0d70..20b9250e9b7fbf3c252e20dff8891bfeeb5112dd 100644 (file)
--- a/stdin.c
+++ b/stdin.c
@@ -69,6 +69,12 @@ static int stdin_post_select(struct sched *s, struct task *t)
        sz = btr_pool_get_buffer(sit->btrp, &buf);
        if (sz == 0)
                return 0;
+       if (sit->must_set_nonblock_flag) {
+               ret = mark_fd_nonblocking(STDIN_FILENO);
+               if (ret < 0)
+                       goto err;
+               sit->must_set_nonblock_flag = false;
+       }
        /*
         * Do not use the maximal size to avoid having only a single buffer
         * reference for the whole pool. This is bad because if that single
@@ -82,6 +88,8 @@ static int stdin_post_select(struct sched *s, struct task *t)
                return 0;
 err:
        btr_remove_node(&sit->btrn);
+       /* Revert to blocking mode if necessary. */
+       fcntl(STDIN_FILENO, F_SETFL, sit->fd_flags);
        //btr_pool_free(sit->btrp);
        return ret;
 }
@@ -92,8 +100,7 @@ err:
  * \param sit The stdin task structure.
  *
  * This fills in the pre/post select function pointers of the task structure
- * given by \a sit. Moreover, the stdin file desctiptor is set to nonblocking
- * mode, and a buffer tree is created.
+ * given by \a sit and creates a buffer tree for I/O.
  */
 void stdin_set_defaults(struct stdin_task *sit)
 {
@@ -103,9 +110,18 @@ void stdin_set_defaults(struct stdin_task *sit)
        sit->task.post_select = stdin_post_select;
        sit->btrp = btr_pool_new("stdin", 128 * 1024);
        sprintf(sit->task.status, "stdin reader");
-       ret = mark_fd_nonblocking(STDIN_FILENO);
-       if (ret >= 0)
-               return;
-       PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-       exit(EXIT_FAILURE);
+       /*
+        * Both STDIN_FILENO and STDOUT_FILENO may refer to the same open file
+        * description (the terminal), and thus share the same file status
+        * flags. In order to not interfere with the stdout task, we only get
+        * the file status flags for STDIN here and save a copy. The nonblock
+        * flag is set later on the first read.
+        */
+       ret = fcntl(STDIN_FILENO, F_GETFL);
+       if (ret < 0) {
+               PARA_EMERG_LOG("F_GETFL: %s\n", strerror(errno));
+               exit(EXIT_FAILURE);
+       }
+       sit->fd_flags = ret;
+       sit->must_set_nonblock_flag = (sit->fd_flags & O_NONBLOCK) == 0;
 }