2 * Copyright (C) 2006-2008 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file stdout.c Functions that deal with writing to stdout. */
9 #include <dirent.h> /* readdir() */
21 * The pre_select function of the stdout task.
23 * \param s The scheduler this task was registered to.
24 * \param t The task structure of the stdout task.
26 * This function is always successful. If there is data available in the input
27 * buffer, it adds \p STDOUT_FILENO to the write fd set of \a s.
29 static void stdout_pre_select(struct sched *s, struct task *t)
31 struct stdout_task *sot = t->private_data;
36 if (*sot->input_error) {
37 t->ret = *sot->input_error;
38 s->timeout.tv_sec = 0;
39 s->timeout.tv_usec = 1;
44 para_fd_set(STDOUT_FILENO, &s->wfds, &s->max_fileno);
48 * The post select function of the stdout task.
50 * \param s The scheduler this task was registered to.
51 * \param t The task structure of the stdout task.
53 * This function checks if \p STDOUT_FILENO was included by in the write fd set
54 * of \a s during the previous pre_select call. If yes, and \p STDOUT_FILENO
55 * appeears to be writable, the data loaded in the input buffer is written to
58 static void stdout_post_select(struct sched *s, struct task *t)
60 struct stdout_task *sot = t->private_data;
65 if (*sot->input_error)
66 t->ret = *sot->input_error;
69 if (!FD_ISSET(STDOUT_FILENO, &s->wfds))
71 t->ret = -E_STDOUT_WRITE;
72 ret = write(STDOUT_FILENO, sot->buf, *sot->loaded);
77 memmove(sot->buf, sot->buf + ret, *sot->loaded);
81 static void stdout_default_event_handler(struct task *t)
83 PARA_NOTICE_LOG("%p: %s\n", t, para_strerror(-t->ret));
88 * Initialize a stdout task structure with default values.
90 * \param sot The stdout task structure.
92 * This fills in the pre/post select function poinzters of the task structure
93 * given by \a sot. It also sets up a default error handler which unregisters
94 * the task on errors and clears the eof flag of \a sot.
96 void stdout_set_defaults(struct stdout_task *sot)
100 sot->task.private_data = sot;
101 sot->task.pre_select = stdout_pre_select;
102 sot->task.post_select = stdout_post_select;
103 sot->task.event_handler = stdout_default_event_handler;
105 sprintf(sot->task.status, "stdout writer");
106 ret = mark_fd_nonblocking(STDOUT_FILENO);
109 PARA_EMERG_LOG("%s\n", para_strerror(-ret));