stdin: Use buffer pools.

[paraslash.git] / stdin.c

diff --git a/stdin.c b/stdin.c
index d080e2165b169ec3fd03bf0c669ac6ec05188985..4329e144a04ae2921a710bd28a3faae710f6b17f 100644 (file)
--- a/stdin.c
+++ b/stdin.c
@@ -46,24 +46,18 @@ static void stdin_pre_select(struct sched *s, struct task *t)
        para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
 }
 
-#define STDIN_MAX_PENDING (1024 * 1024)
-
 static void stdin_pre_select_btr(struct sched *s, struct task *t)
 {
        struct stdin_task *sit = container_of(t, struct stdin_task, task);
+       int ret;
 
-       if (btr_no_children(sit->btrn)) {
-               t->error = -E_STDIN_NO_CHILD;
-               btr_del_node(sit->btrn);
-               sit->btrn = NULL;
-               return;
-       }
        t->error = 0;
-       if (btr_bytes_pending(sit->btrn) > STDIN_MAX_PENDING)
-               sit->check_fd = 0;
-       else {
-               sit->check_fd = 1;
+       ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
+       if (ret > 0)
                para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
+       else if (ret < 0) {
+               s->timeout.tv_sec = 0;
+               s->timeout.tv_usec = 1;
        }
 }
 
@@ -101,37 +95,45 @@ static void stdin_post_select(struct sched *s, struct task *t)
                t->error = -E_STDIN_EOF;
 }
 
-#define STDIN_INPUT_BUFFER_SIZE 4000
 static void stdin_post_select_btr(struct sched *s, struct task *t)
 {
        struct stdin_task *sit = container_of(t, struct stdin_task, task);
        ssize_t ret;
+       size_t sz;
        char *buf = NULL;
 
-       t->error = -E_STDIN_NO_CHILD;
-       if (btr_no_children(sit->btrn))
-               goto err;
-
        t->error = 0;
-       if (!sit->check_fd)
+       ret = btr_node_status(sit->btrn, 0, BTR_NT_ROOT);
+       if (ret < 0)
+               goto err;
+       if (ret == 0)
                return;
        if (!FD_ISSET(STDIN_FILENO, &s->rfds))
                return;
-
-       buf = para_malloc(STDIN_INPUT_BUFFER_SIZE);
-       ret = read(STDIN_FILENO, buf, STDIN_INPUT_BUFFER_SIZE);
+       sz = btr_pool_get_buffer(sit->btrp, &buf);
+       ret = -E_STDIN_OVERRUN;
+       if (sz == 0)
+               goto err;
+       /*
+        * 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(STDIN_FILENO, buf, sz);
+       //PARA_CRIT_LOG("read ret: %d\n", ret);
        if (ret < 0)
-               t->error = -ERRNO_TO_PARA_ERROR(errno);
+               ret = -ERRNO_TO_PARA_ERROR(errno);
        if (ret == 0)
-               t->error = -E_STDIN_EOF;
-       if (t->error < 0)
+               ret = -E_STDIN_EOF;
+       if (ret < 0)
                goto err;
-       btr_add_output(buf, ret, sit->btrn);
+       btr_add_output_pool(sit->btrp, ret, sit->btrn);
        return;
 err:
-       free(buf);
-       btr_del_node(sit->btrn);
-       sit->btrn = NULL;
+       btr_remove_node(sit->btrn);
+       //btr_pool_free(sit->btrp);
+       t->error = ret;
 }
 
 /**
@@ -141,7 +143,7 @@ err:
  *
  * 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 bufsize is initialized to 16 KB (but no buffer is allocated).
+ * mode and \a bufsize is initialized (but no buffer is allocated).
  */
 void stdin_set_defaults(struct stdin_task *sit)
 {
@@ -151,6 +153,7 @@ void stdin_set_defaults(struct stdin_task *sit)
        if (sit->btrn) {
                sit->task.pre_select = stdin_pre_select_btr;
                sit->task.post_select = stdin_post_select_btr;
+               sit->btrp = btr_pool_new("stdin", 64 * 1024);
        } else {
                sit->task.pre_select = stdin_pre_select;
                sit->task.post_select = stdin_post_select;