X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=stdin.c;h=20b9250e9b7fbf3c252e20dff8891bfeeb5112dd;hp=79a9a3231d8a675c94f49ee6e0c0a98069ae6d0c;hb=38657223b245405602bc50906a9687ce98f53857;hpb=eecc102ad0abeb0335fe994bb72031a15b9090d7

diff --git a/stdin.c b/stdin.c
index 79a9a323..20b9250e 100644
--- a/stdin.c
+++ b/stdin.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 stdin.c Functions that deal with reading from stdin. */
 
-#include <dirent.h> /* readdir() */
 #include <assert.h>
-#include <stdbool.h>
 #include <regex.h>
 
 #include "para.h"
@@ -35,7 +33,6 @@ static void stdin_pre_select(struct sched *s, struct task *t)
 	struct stdin_task *sit = container_of(t, struct stdin_task, task);
 	int ret;
 
-	t->error = 0;
 	ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
 	if (ret < 0)
 		sched_min_delay(s);
@@ -57,43 +54,44 @@ static void stdin_pre_select(struct sched *s, struct task *t)
  * appears to be readable, data is read from stdin and fed into the buffer
  * tree.
  */
-static void stdin_post_select(struct sched *s, struct task *t)
+static int stdin_post_select(struct sched *s, struct task *t)
 {
 	struct stdin_task *sit = container_of(t, struct stdin_task, task);
 	ssize_t ret;
-	size_t sz;
+	size_t sz, n;
 	char *buf = NULL;
 
-	t->error = 0;
 	ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
 	if (ret < 0)
 		goto err;
 	if (ret == 0)
-		return;
-	if (!FD_ISSET(STDIN_FILENO, &s->rfds))
-		return;
+		return 0;
 	sz = btr_pool_get_buffer(sit->btrp, &buf);
 	if (sz == 0)
-		return;
+		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
 	 * reference can not be freed, we're stuck.
 	 */
 	sz = PARA_MIN(sz, btr_pool_size(sit->btrp) / 2);
-	ret = read(STDIN_FILENO, buf, sz);
-	if (ret < 0)
-		ret = -ERRNO_TO_PARA_ERROR(errno);
-	if (ret == 0)
-		ret = -E_STDIN_EOF;
-	if (ret < 0)
-		goto err;
-	btr_add_output_pool(sit->btrp, ret, sit->btrn);
-	return;
+	ret = read_nonblock(STDIN_FILENO, buf, sz, &s->rfds, &n);
+	if (n > 0)
+		btr_add_output_pool(sit->btrp, n, sit->btrn);
+	if (ret >= 0)
+		return 0;
 err:
-	btr_remove_node(sit->btrn);
+	btr_remove_node(&sit->btrn);
+	/* Revert to blocking mode if necessary. */
+	fcntl(STDIN_FILENO, F_SETFL, sit->fd_flags);
 	//btr_pool_free(sit->btrp);
-	t->error = ret;
+	return ret;
 }
 
 /**
@@ -102,8 +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)
 {
@@ -111,11 +108,20 @@ void stdin_set_defaults(struct stdin_task *sit)
 
 	sit->task.pre_select = stdin_pre_select;
 	sit->task.post_select = stdin_post_select;
-	sit->btrp = btr_pool_new("stdin", 64 * 1024);
+	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;
 }