/*
- * Copyright (C) 2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
-/** \file stdout.c functions that deal with writing to stdout */
+/** \file stdout.c Functions that deal with writing to stdout. */
#include "para.h"
-#include "string.h"
#include "list.h"
#include "sched.h"
#include "fd.h"
#include "error.h"
#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 data available in the input
- * buffer, it adds \p STDOUT_FILENO to the write fd set of \a s.
- */
-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 = t->private_data;
+ struct stdout_task *sot = context;
+ int ret;
- t->ret = 1;
- sot->check_fd = 0;
- if (!*sot->loaded) {
- if (*sot->input_eof) {
- t->ret = -E_STDOUT_EOF;
- 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);
+ 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)
+ 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 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
+ * STDOUT_FILENO is writable.
*/
-void stdout_post_select(struct sched *s, struct task *t)
+static int stdout_post_select(struct sched *s, void *context)
{
- struct stdout_task *sot = t->private_data;
- ssize_t ret;
+ struct stdout_task *sot = context;
+ struct btr_node *btrn = sot->btrn;
+ int ret;
+ char *buf;
+ size_t sz;
- t->ret = 1;
- if (!sot->check_fd) {
- if (*sot->input_eof)
- t->ret = -E_STDOUT_EOF;
- return;
- }
+ ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
+ if (ret < 0)
+ goto out;
+ if (ret == 0)
+ return 0;
if (!FD_ISSET(STDOUT_FILENO, &s->wfds))
- return;
- t->ret = -E_STDOUT_WRITE;
- ret = write(STDOUT_FILENO, sot->buf, *sot->loaded);
- if (ret <= 0)
- return;
- *sot->loaded -= ret;
- t->ret = 1;
-}
+ return 0;
-static void stdout_default_event_handler(struct task *t)
-{
- PARA_NOTICE_LOG("%p: %s\n", t, PARA_STRERROR(-t->ret));
- unregister_task(t);
+ 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 = xwrite(STDOUT_FILENO, buf, sz);
+ if (ret <= 0)
+ break;
+ btr_consume(btrn, ret);
+ }
+out:
+ 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 poinzters of the task structure
- * given by \a sot. It also sets up a default error handler which unregisters
- * the task on errors and clears the eof flag of \a sot.
+ * 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)
{
- sot->task.private_data = sot;
- sot->task.pre_select = stdout_pre_select;
- sot->task.post_select = stdout_post_select;
- sot->task.event_handler = stdout_default_event_handler;
- sot->eof = 0;
- mark_fd_nonblock(STDOUT_FILENO);
- sprintf(sot->task.status, "stdout writer");
+ int ret;
+ struct task_info ti = {
+ .pre_select = stdout_pre_select,
+ .post_select = stdout_post_select,
+ .context = sot,
+ .name = "stdout",
+ };
+
+ /* 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;
+ sot->task = task_register(&ti, s);
}