2 * Copyright (C) 2006-2009 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() */
19 #include "buffer_tree.h"
22 * The pre_select function of the stdout task.
24 * \param s The scheduler this task was registered to.
25 * \param t The task structure of the stdout task.
27 * This function is always successful. If there is data available in the input
28 * buffer, it adds \p STDOUT_FILENO to the write fd set of \a s.
30 static void stdout_pre_select(struct sched *s, struct task *t)
32 struct stdout_task *sot = container_of(t, struct stdout_task, task);
37 if (*sot->input_error < 0) {
38 t->error = *sot->input_error;
39 s->timeout.tv_sec = 0;
40 s->timeout.tv_usec = 1;
45 para_fd_set(STDOUT_FILENO, &s->wfds, &s->max_fileno);
48 static void stdout_pre_select_btr(struct sched *s, struct task *t)
50 struct stdout_task *sot = container_of(t, struct stdout_task, task);
51 size_t sz = btr_get_input_queue_size(sot->btrn);
56 if (btr_no_parent(sot->btrn)) {
58 btr_del_node(sot->btrn);
59 s->timeout.tv_sec = 0;
60 s->timeout.tv_usec = 1;
65 para_fd_set(STDOUT_FILENO, &s->wfds, &s->max_fileno);
69 * The post select function of the stdout task.
71 * \param s The scheduler this task was registered to.
72 * \param t The task structure of the stdout task.
74 * This function checks if \p STDOUT_FILENO was included by in the write fd set
75 * of \a s during the previous pre_select call. If yes, and \p STDOUT_FILENO
76 * appeears to be writable, the data loaded in the input buffer is written to
79 static void stdout_post_select(struct sched *s, struct task *t)
81 struct stdout_task *sot = container_of(t, struct stdout_task, task);
86 if (!*sot->loaded && *sot->input_error < 0)
87 t->error = *sot->input_error;
90 if (!FD_ISSET(STDOUT_FILENO, &s->wfds))
92 ret = write(STDOUT_FILENO, *sot->bufp, *sot->loaded);
94 t->error = -ERRNO_TO_PARA_ERROR(errno);
99 memmove(*sot->bufp, *sot->bufp + ret, *sot->loaded);
102 static void stdout_post_select_btr(struct sched *s, struct task *t)
104 struct stdout_task *sot = container_of(t, struct stdout_task, task);
106 size_t sz = btr_get_input_queue_size(sot->btrn);
107 bool orphan = btr_no_parent(sot->btrn);
111 if (!sot->check_fd) {
112 if (sz == 0 && orphan) {
113 t->error = -E_ORPHAN;
118 if (!FD_ISSET(STDOUT_FILENO, &s->wfds))
120 sz = btr_next_buffer(sot->btrn, &buf);
123 ret = write(STDOUT_FILENO, buf, sz);
125 t->error = -ERRNO_TO_PARA_ERROR(errno);
128 btr_consume(sot->btrn, ret);
131 btr_del_node(sot->btrn);
134 * Initialize a stdout task structure with default values.
136 * \param sot The stdout task structure.
138 * This fills in the pre/post select function poinzters of the task structure
141 void stdout_set_defaults(struct stdout_task *sot)
146 sot->task.pre_select = stdout_pre_select_btr;
147 sot->task.post_select = stdout_post_select_btr;
149 sot->task.pre_select = stdout_pre_select;
150 sot->task.post_select = stdout_post_select;
152 sprintf(sot->task.status, "stdout writer");
153 ret = mark_fd_nonblocking(STDOUT_FILENO);
156 PARA_EMERG_LOG("%s\n", para_strerror(-ret));