+/*
+ * Copyright (C) 2006 Andre Noll <maan@systemlinux.org>
+ *
+ * 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.
+ */
+
+/** \file stdin.c functions that deal with reading from stdin */
+
#include "para.h"
#include "string.h"
#include "list.h"
#include "error.h"
#include "stdin.h"
+/**
+ * the pre_select function of the stdin task
+ *
+ * \param s the scheduler this task was registered to
+ * \param t the task structure of the stdin task
+ *
+ * This function is always successful. If there is space left in the
+ * buffer of the stdin task, it adds \p STDIN_FILENO to the read fd set
+ * of \a s.
+ */
void stdin_pre_select(struct sched *s, struct task *t)
{
struct stdin_task *sit = t->private_data;
- if (sit->loaded < sit->bufsize)
- para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
- t->ret = 1; /* success */
+ t->ret = 1;
+ sit->check_fd = 0;
+ if (sit->loaded >= sit->bufsize)
+ return;
+ sit->check_fd = 1;
+ para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
+}
+
+static void stdin_default_event_handler(struct task *t)
+{
+ PARA_NOTICE_LOG("%p: %s\n", t, PARA_STRERROR(-t->ret));
+ unregister_task(t);
}
+/**
+ * the post select function of the stdin task
+ *
+ * \param s the scheduler this task was registered to
+ * \param t the task structure of the stdin task
+ *
+ * This function checks if \p STDIN_FILENO was included by in the read fd set
+ * of \a s during the previous pre_select call. If yes, and \p STDIN_FILENO
+ * appeears to be readable, data is read from stdin into the buffer of the
+ * stdin task.
+ */
void stdin_post_select(struct sched *s, struct task *t)
{
struct stdin_task *sit = t->private_data;
ssize_t ret;
t->ret = 1;
- if (sit->loaded >= sit->bufsize)
+ if (!sit->check_fd)
return;
if (!FD_ISSET(STDIN_FILENO, &s->rfds))
return;
sit->loaded += ret;
t->ret = ret;
} else
- t->ret = 0;
- if (ret <= 0)
+ t->ret = -E_STDIN_EOF;
+ if (t->ret < 0)
sit->eof = 1;
- sprintf(t->status,
- "%p stdin reader: loaded = %d, ret = %d",
- sit, sit->loaded, t->ret);
+}
+
+/**
+ * initialize a stdin task structure with default values
+ *
+ * \param sit the stdin task structure
+ *
+ * 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. Moreover, \a loaded and \a eof are set to zero and \a bufsize is
+ * initialized to 16 KB (but no buffer is allocated).
+ */
+void stdin_set_defaults(struct stdin_task *sit)
+{
+ sit->bufsize = 16 * 1024,
+ sit->loaded = 0,
+ sit->eof = 0,
+ sit->task.pre_select = stdin_pre_select;
+ sit->task.post_select = stdin_post_select;
+ sit->task.event_handler = stdin_default_event_handler;
+ sit->task.private_data = sit;
+ mark_fd_nonblock(STDIN_FILENO);
+ sprintf(sit->task.status, "stdin reader");
}