X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=stdout.c;h=1f7791094a33a961c193c273a4c09e9b16f2be07;hp=a2ee2aca6af8114eadf92539092bcca9bb7d0e09;hb=e32a0e7295c6386b421956553ae577a7df1abf8e;hpb=d7b4aa3835197ee906f13f515040e1cda6385544;ds=sidebyside

diff --git a/stdout.c b/stdout.c
index a2ee2aca..1f779109 100644
--- a/stdout.c
+++ b/stdout.c
@@ -1,14 +1,7 @@
-/*
- * Copyright (C) 2006-2011 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file stdout.c Functions that deal with writing to stdout. */
 
-#include <assert.h>
-#include <stdbool.h>
-
 #include "para.h"
 #include "list.h"
 #include "sched.h"
@@ -17,21 +10,12 @@
 #include "stdout.h"
 #include "buffer_tree.h"
 
-/**
- * The pre_select function of the stdout task.
- *
- * \param s The scheduler this task was registered to.
- * \param t The task structure of the stdout task.
- *
- * This function is always successful. If there is input data available, it
- * adds \p STDOUT_FILENO to the write fd set of \a s.
- */
-static void stdout_pre_select(struct sched *s, struct task *t)
+/* Add STDOUT_FILENO to the write fd set if there is input data available. */
+static void stdout_pre_select(struct sched *s, void *context)
 {
-	struct stdout_task *sot = container_of(t, struct stdout_task, task);
+	struct stdout_task *sot = context;
 	int ret;
 
-	t->error = 0;
 	ret = btr_node_status(sot->btrn, 0, BTR_NT_LEAF);
 	if (ret > 0)
 		para_fd_set(STDOUT_FILENO, &s->wfds, &s->max_fileno);
@@ -39,64 +23,76 @@ static void stdout_pre_select(struct sched *s, struct task *t)
 		sched_min_delay(s);
 }
 
-/**
- * The post select function of the stdout task.
- *
- * \param s The scheduler this task was registered to.
- * \param t The task structure of the stdout task.
- *
- * This function writes input data from the buffer tree to stdout if \p
+/*
+ * This function writes input data from the buffer tree to stdout if
  * STDOUT_FILENO is writable.
  */
-static void stdout_post_select(struct sched *s, struct task *t)
+static int stdout_post_select(struct sched *s, void *context)
 {
-	struct stdout_task *sot = container_of(t, struct stdout_task, task);
+	struct stdout_task *sot = context;
 	struct btr_node *btrn = sot->btrn;
 	int ret;
 	char *buf;
 	size_t sz;
 
-	t->error = 0;
 	ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
 	if (ret < 0)
 		goto out;
 	if (ret == 0)
-		return;
+		return 0;
 	if (!FD_ISSET(STDOUT_FILENO, &s->wfds))
-		return;
+		return 0;
 
+	if (sot->must_set_nonblock_flag) {
+		ret = mark_fd_nonblocking(STDOUT_FILENO);
+		if (ret < 0)
+			goto out;
+		sot->must_set_nonblock_flag = false;
+	}
 	for (;;) {
 		sz = btr_next_buffer(btrn, &buf);
 		if (sz == 0)
 			break;
-		ret = write_nonblock(STDOUT_FILENO, buf, sz);
+		ret = xwrite(STDOUT_FILENO, buf, sz);
 		if (ret <= 0)
 			break;
 		btr_consume(btrn, ret);
 	}
 out:
-	if (ret < 0)
-		btr_remove_node(btrn);
-	t->error = ret;
+	if (ret < 0) {
+		btr_remove_node(&sot->btrn);
+		/* Revert to blocking mode if necessary. */
+		fcntl(STDOUT_FILENO, F_SETFL, sot->fd_flags);
+	}
+	return ret;
 }
+
 /**
- * Initialize a stdout task structure with default values.
+ * Register a stdout task structure.
  *
- * \param sot The stdout task structure.
+ * \param sot The stdout task structure to register.
+ * \param s The task will be added to this scheduler's task list.
  *
- * This fills in the pre/post select function pointers of the task structure
- * given by \a sot and sets the stdout file descriptor to nonblocking mode.
+ * This sets up \a sot and registers a task with \a sot as context pointer.
  */
-void stdout_set_defaults(struct stdout_task *sot)
+void stdout_task_register(struct stdout_task *sot, struct sched *s)
 {
 	int ret;
+	struct task_info ti = {
+		.pre_select = stdout_pre_select,
+		.post_select = stdout_post_select,
+		.context = sot,
+		.name = "stdout",
+	};
 
-	sot->task.pre_select = stdout_pre_select;
-	sot->task.post_select = stdout_post_select;
-	sprintf(sot->task.status, "stdout");
-	ret = mark_fd_nonblocking(STDOUT_FILENO);
-	if (ret >= 0)
-		return;
-	PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-	exit(EXIT_FAILURE);
+	/* See \ref stdin.c for details. */
+	ret = fcntl(STDOUT_FILENO, F_GETFL);
+	if (ret < 0) {
+		PARA_EMERG_LOG("F_GETFL: %s\n", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+	sot->fd_flags = ret;
+	sot->must_set_nonblock_flag = (sot->fd_flags & O_NONBLOCK) == 0
+		&& !isatty(STDOUT_FILENO);
+	sot->task = task_register(&ti, s);
 }