X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=stdin.c;h=e5c40bcb092a1faa59a91a33bd2d7b1975f1f3e7;hp=22f1dd97b2bb6b18d028b890dd6b73eab73fa567;hb=0829285d0c0252b2bf3e428760b46c2d0e4dfff2;hpb=2a8029478dfc65f0c935d864faf4aea9e3deb27d

diff --git a/stdin.c b/stdin.c
index 22f1dd97..e5c40bcb 100644
--- a/stdin.c
+++ b/stdin.c
@@ -1,56 +1,119 @@
+/*
+ * Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+
+/** \file stdin.c Functions that deal with reading from stdin. */
+
+#include <regex.h>
+
 #include "para.h"
-#include "string.h"
 #include "list.h"
 #include "sched.h"
 #include "fd.h"
 #include "error.h"
 #include "stdin.h"
+#include "buffer_tree.h"
+#include "string.h"
 
-void stdin_pre_select(struct sched *s, struct task *t)
+/*
+ * If there is space left in the buffer of the stdin task add STDIN_FILENO to
+ * the read fd set of s.
+ */
+static void stdin_pre_select(struct sched *s, void *context)
 {
-	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 */
-}
+	struct stdin_task *sit = context;
+	int ret;
 
-static void stdin_default_event_handler(struct task *t)
-{
-	PARA_NOTICE_LOG("%p: %s\n", t, PARA_STRERROR(-t->ret));
-	unregister_task(t);
+	ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
+	if (ret < 0)
+		sched_min_delay(s);
+	if (ret <= 0)
+		return;
+	if (btr_pool_unused(sit->btrp) > 0)
+		return para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
+	sched_request_timeout_ms(100, s);
 }
 
-void stdin_post_select(struct sched *s, struct task *t)
+/*
+ * This function checks if STDIN_FILENO was included by in the read fd set of s
+ * during the previous pre_select call. If so, and if STDIN_FILENO is readable,
+ * data is read from stdin and fed into the buffer tree.
+ */
+static int stdin_post_select(struct sched *s, void *context)
 {
-	struct stdin_task *sit = t->private_data;
+	struct stdin_task *sit = context;
 	ssize_t ret;
+	size_t sz, n;
+	char *buf = NULL;
 
-	t->ret = 1;
-	if (sit->loaded >= sit->bufsize)
-		return;
-	if (!FD_ISSET(STDIN_FILENO, &s->rfds))
-		return;
-	ret = read(STDIN_FILENO, sit->buf + sit->loaded, sit->bufsize - sit->loaded);
+	ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
 	if (ret < 0)
-		t->ret = -E_STDIN_READ;
-	else if (ret > 0) {
-		sit->loaded += ret;
-		t->ret = ret;
-	} else
-		t->ret = -E_STDIN_EOF;
-	if (t->ret < 0)
-		sit->eof = 1;
+		goto err;
+	if (ret == 0)
+		return 0;
+	sz = btr_pool_get_buffer(sit->btrp, &buf);
+	if (sz == 0)
+		return 0;
+	if (sit->must_set_nonblock_flag) {
+		ret = mark_fd_nonblocking(STDIN_FILENO);
+		if (ret < 0)
+			goto err;
+		sit->must_set_nonblock_flag = false;
+	}
+	/*
+	 * Do not use the maximal size to avoid having only a single buffer
+	 * reference for the whole pool. This is bad because if that single
+	 * reference can not be freed, we're stuck.
+	 */
+	sz = PARA_MIN(sz, btr_pool_size(sit->btrp) / 2);
+	ret = read_nonblock(STDIN_FILENO, buf, sz, &s->rfds, &n);
+	if (n > 0)
+		btr_add_output_pool(sit->btrp, n, sit->btrn);
+	if (ret >= 0)
+		return 0;
+err:
+	btr_remove_node(&sit->btrn);
+	/* Revert to blocking mode if necessary. */
+	fcntl(STDIN_FILENO, F_SETFL, sit->fd_flags);
+	//btr_pool_free(sit->btrp);
+	return ret;
 }
 
-void stdin_set_defaults(struct stdin_task *sit)
+/**
+ * Register a stdin task structure.
+ *
+ * \param sit The stdin task structure to register.
+ * \param s The task will be added to this scheduler's task list.
+ *
+ * This allocates a buffer tree pool for I/O, sets up \a sit and registers a
+ * task with \a sit as context pointer.
+ */
+void stdin_task_register(struct stdin_task *sit, struct sched *s)
 {
-	sit->bufsize = 16 * 1024,
-	sit->loaded = 0,
-	sit->eof = 0,
-	sit->task.flags = 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;
-	sprintf(sit->task.status, "stdin reader");
+	int ret;
+	struct task_info ti = {
+		.name = "stdin",
+		.pre_select = stdin_pre_select,
+		.post_select = stdin_post_select,
+		.context = sit,
+	};
+
+	sit->btrp = btr_pool_new("stdin", 128 * 1024);
+	/*
+	 * Both STDIN_FILENO and STDOUT_FILENO may refer to the same open file
+	 * description (the terminal), and thus share the same file status
+	 * flags. In order to not interfere with the stdout task, we only get
+	 * the file status flags for STDIN here and save a copy. The nonblock
+	 * flag is set later on the first read.
+	 */
+	ret = fcntl(STDIN_FILENO, F_GETFL);
+	if (ret < 0) {
+		PARA_EMERG_LOG("F_GETFL: %s\n", strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+	sit->fd_flags = ret;
+	sit->must_set_nonblock_flag = (sit->fd_flags & O_NONBLOCK) == 0;
+	sit->task = task_register(&ti, s);
 }