X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=stdout.c;h=cf33bf6d0b67cf49625d27b4d602dec35922d32d;hp=34fe08cd6a46e8305fa990988b1408f056fad191;hb=f87e1a2d4f50160aa2e24c9d771771f086ce4db6;hpb=3bb5d9c5f7e30c5b4d2216171ee9aff1389d70ae

diff --git a/stdout.c b/stdout.c
index 34fe08cd..cf33bf6d 100644
--- a/stdout.c
+++ b/stdout.c
@@ -1,14 +1,12 @@
 /*
- * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2013 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
 /** \file stdout.c Functions that deal with writing to stdout. */
 
-#include <dirent.h> /* readdir() */
 #include <assert.h>
-#include <stdbool.h>
 
 #include "para.h"
 #include "list.h"
@@ -24,41 +22,19 @@
  * \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 data available in the input
- * buffer, it adds \p STDOUT_FILENO to the write fd set of \a s.
+ * 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)
-{
-	struct stdout_task *sot = container_of(t, struct stdout_task, task);
-
-	t->error = 0;
-	sot->check_fd = 0;
-	if (!*sot->loaded) {
-		if (*sot->input_error < 0) {
-			t->error = *sot->input_error;
-			s->timeout.tv_sec = 0;
-			s->timeout.tv_usec = 1;
-		}
-		return;
-	}
-	sot->check_fd = 1;
-	para_fd_set(STDOUT_FILENO, &s->wfds, &s->max_fileno);
-}
-
-static void stdout_pre_select_btr(struct sched *s, struct task *t)
 {
 	struct stdout_task *sot = container_of(t, struct stdout_task, task);
 	int ret;
 
-	t->error = 0;
-	sot->check_fd = 0;
 	ret = btr_node_status(sot->btrn, 0, BTR_NT_LEAF);
 	if (ret > 0)
 		para_fd_set(STDOUT_FILENO, &s->wfds, &s->max_fileno);
-	else if (ret < 0) {
-		s->timeout.tv_sec = 0;
-		s->timeout.tv_usec = 1;
-	}
+	else if (ret < 0)
+		sched_min_delay(s);
 }
 
 /**
@@ -67,35 +43,10 @@ static void stdout_pre_select_btr(struct sched *s, struct task *t)
  * \param s The scheduler this task was registered to.
  * \param t The task structure of the stdout task.
  *
- * This function checks if \p STDOUT_FILENO was included by in the write fd set
- * of \a s during the previous pre_select call.  If yes, and \p STDOUT_FILENO
- * appeears to be writable, the data loaded in the input buffer is written to
- * stdout.
+ * This function writes input data from the buffer tree to stdout if \p
+ * STDOUT_FILENO is writable.
  */
-static void stdout_post_select(struct sched *s, struct task *t)
-{
-	struct stdout_task *sot = container_of(t, struct stdout_task, task);
-	ssize_t ret;
-
-	t->error = 0;
-	if (!sot->check_fd) {
-		if (!*sot->loaded && *sot->input_error < 0)
-			t->error = *sot->input_error;
-		return;
-	}
-	if (!FD_ISSET(STDOUT_FILENO, &s->wfds))
-		return;
-	ret = write(STDOUT_FILENO, *sot->bufp, *sot->loaded);
-	if (ret < 0) {
-		t->error = -ERRNO_TO_PARA_ERROR(errno);
-		return;
-	}
-	*sot->loaded -= ret;
-	if (*sot->loaded)
-		memmove(*sot->bufp, *sot->bufp + ret, *sot->loaded);
-}
-
-static void stdout_post_select_btr(struct sched *s, struct task *t)
+static int stdout_post_select(struct sched *s, struct task *t)
 {
 	struct stdout_task *sot = container_of(t, struct stdout_task, task);
 	struct btr_node *btrn = sot->btrn;
@@ -103,28 +54,36 @@ static void stdout_post_select_btr(struct sched *s, struct task *t)
 	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, 0);
+		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.
@@ -138,17 +97,16 @@ void stdout_set_defaults(struct stdout_task *sot)
 {
 	int ret;
 
-	if (sot->btrn) {
-		sot->task.pre_select = stdout_pre_select_btr;
-		sot->task.post_select = stdout_post_select_btr;
-	} else {
-		sot->task.pre_select = stdout_pre_select;
-		sot->task.post_select = stdout_post_select;
-	}
+	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 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;
 }