write: Remove osx writer from write_cmd suite.

[paraslash.git] / stdin.c

diff --git a/stdin.c b/stdin.c
index fd803ae5441acf01446dadab89c35d3bec14cecd..9408235a045a6767e2acf443208d95196990d379 100644 (file)
--- a/stdin.c
+++ b/stdin.c
@@ -1,12 +1,7 @@
-/*
- * Copyright (C) 2006-2013 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
 /** \file stdin.c Functions that deal with reading from stdin. */
 
-#include <assert.h>
 #include <regex.h>
 
 #include "para.h"
@@ -18,22 +13,15 @@
 #include "buffer_tree.h"
 #include "string.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.
+/*
+ * 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, struct task *t)
+static void stdin_pre_select(struct sched *s, void *context)
 {
-       struct stdin_task *sit = container_of(t, struct stdin_task, task);
+       struct stdin_task *sit = context;
        int ret;
 
-       t->error = 0;
        ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
        if (ret < 0)
                sched_min_delay(s);
@@ -44,33 +32,32 @@ static void stdin_pre_select(struct sched *s, struct task *t)
        sched_request_timeout_ms(100, s);
 }
 
-/**
- * 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
- * appears to be readable, data is read from stdin and fed into the buffer
- * tree.
+/*
+ * 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 void stdin_post_select(struct sched *s, struct task *t)
+static int stdin_post_select(struct sched *s, void *context)
 {
-       struct stdin_task *sit = container_of(t, struct stdin_task, task);
+       struct stdin_task *sit = context;
        ssize_t ret;
        size_t sz, n;
        char *buf = NULL;
 
-       t->error = 0;
        ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
        if (ret < 0)
                goto err;
        if (ret == 0)
-               return;
+               return 0;
        sz = btr_pool_get_buffer(sit->btrp, &buf);
        if (sz == 0)
-               return;
+               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
@@ -81,33 +68,49 @@ static void stdin_post_select(struct sched *s, struct task *t)
        if (n > 0)
                btr_add_output_pool(sit->btrp, n, sit->btrn);
        if (ret >= 0)
-               return;
+               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);
-       t->error = ret;
+       return ret;
 }
 
 /**
- * Initialize a stdin task structure with default values.
+ * Register a stdin task structure.
  *
- * \param sit The 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 fills in the pre/post select function pointers of the task structure
- * given by \a sit. Moreover, the stdin file desctiptor is set to nonblocking
- * mode, and a buffer tree is created.
+ * 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_set_defaults(struct stdin_task *sit)
+void stdin_task_register(struct stdin_task *sit, struct sched *s)
 {
        int ret;
+       struct task_info ti = {
+               .name = "stdin",
+               .pre_select = stdin_pre_select,
+               .post_select = stdin_post_select,
+               .context = sit,
+       };
 
-       sit->task.pre_select = stdin_pre_select;
-       sit->task.post_select = stdin_post_select;
        sit->btrp = btr_pool_new("stdin", 128 * 1024);
-       sprintf(sit->task.status, "stdin reader");
-       ret = mark_fd_nonblocking(STDIN_FILENO);
-       if (ret >= 0)
-               return;
-       PARA_EMERG_LOG("%s\n", para_strerror(-ret));
-       exit(EXIT_FAILURE);
+       /*
+        * 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
+               && !isatty(STDIN_FILENO);
+       sit->task = task_register(&ti, s);
 }