X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=stdout.c;h=cf33bf6d0b67cf49625d27b4d602dec35922d32d;hp=d167cd1460225ad964c343b6129aedcac7c73c65;hb=fb4022dfafa1d6f86f741767ecaed8e41c53352a;hpb=84b0b12f1f485c54f9e78fed1359105c611f8fbf diff --git a/stdout.c b/stdout.c index d167cd14..cf33bf6d 100644 --- a/stdout.c +++ b/stdout.c @@ -1,14 +1,12 @@ /* - * Copyright (C) 2006-2009 Andre Noll + * Copyright (C) 2006-2013 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ /** \file stdout.c Functions that deal with writing to stdout. */ -#include /* readdir() */ #include -#include #include "para.h" #include "list.h" @@ -24,43 +22,19 @@ * \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. + * This function is always successful. If there is input data available, it + * adds \p STDOUT_FILENO to the write fd set of \a s. */ static void stdout_pre_select(struct sched *s, struct task *t) { struct stdout_task *sot = container_of(t, struct stdout_task, task); + int ret; - t->error = 0; - sot->check_fd = 0; - if (!*sot->loaded) { - if (*sot->input_error < 0) { - t->error = *sot->input_error; - 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); -} - -static void stdout_pre_select_btr(struct sched *s, struct task *t) -{ - struct stdout_task *sot = container_of(t, struct stdout_task, task); - size_t sz = btr_get_input_queue_size(sot->btrn); - - t->error = 0; - sot->check_fd = 0; - if (sz == 0) { - if (btr_no_parent(sot->btrn)) { - 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); } /** @@ -69,87 +43,70 @@ static void stdout_pre_select_btr(struct sched *s, struct task *t) * \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 \p + * STDOUT_FILENO is writable. */ -static void stdout_post_select(struct sched *s, struct task *t) +static int stdout_post_select(struct sched *s, struct task *t) { struct stdout_task *sot = container_of(t, struct stdout_task, task); - ssize_t ret; + struct btr_node *btrn = sot->btrn; + int ret; + char *buf; + size_t sz; - t->error = 0; - if (!sot->check_fd) { - if (!*sot->loaded && *sot->input_error < 0) - t->error = *sot->input_error; - 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; - ret = write(STDOUT_FILENO, *sot->bufp, *sot->loaded); - if (ret < 0) { - t->error = -ERRNO_TO_PARA_ERROR(errno); - return; - } - *sot->loaded -= ret; - if (*sot->loaded) - memmove(*sot->bufp, *sot->bufp + ret, *sot->loaded); -} + return 0; -static void stdout_post_select_btr(struct sched *s, struct task *t) -{ - struct stdout_task *sot = container_of(t, struct stdout_task, task); - ssize_t ret; - size_t sz = btr_get_input_queue_size(sot->btrn); - char *buf; - - t->error = 0; - if (!sot->check_fd) { - if (sz == 0 && btr_no_parent(sot->btrn)) { - t->error = -E_ORPHAN; - goto err; - } - return; + if (sot->must_set_nonblock_flag) { + ret = mark_fd_nonblocking(STDOUT_FILENO); + if (ret < 0) + goto out; + sot->must_set_nonblock_flag = false; } - if (!FD_ISSET(STDOUT_FILENO, &s->wfds)) - return; - sz = btr_next_buffer(sot->btrn, &buf); - if (sz == 0) - return; - ret = write_nonblock(STDOUT_FILENO, buf, sz, 0); + 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) { - t->error = -ERRNO_TO_PARA_ERROR(errno); - goto err; + btr_remove_node(&sot->btrn); + /* Revert to blocking mode if necessary. */ + fcntl(STDOUT_FILENO, F_SETFL, sot->fd_flags); } - btr_consume(sot->btrn, ret); - return; -err: - btr_del_node(sot->btrn); + return ret; } /** * Initialize a stdout task structure with default values. * * \param sot The stdout task structure. * - * This fills in the pre/post select function poinzters of the task structure + * This fills in the pre/post select function pointers of the task structure * given by \a sot. */ void stdout_set_defaults(struct stdout_task *sot) { int ret; - if (sot->btrn) { - sot->task.pre_select = stdout_pre_select_btr; - sot->task.post_select = stdout_post_select_btr; - } else { - sot->task.pre_select = stdout_pre_select; - sot->task.post_select = stdout_post_select; + sot->task.pre_select = stdout_pre_select; + sot->task.post_select = stdout_post_select; + sprintf(sot->task.status, "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); } - sprintf(sot->task.status, "stdout writer"); - ret = mark_fd_nonblocking(STDOUT_FILENO); - if (ret >= 0) - return; - PARA_EMERG_LOG("%s\n", para_strerror(-ret)); - exit(EXIT_FAILURE); + sot->fd_flags = ret; + sot->must_set_nonblock_flag = (sot->fd_flags & O_NONBLOCK) == 0; }