Infrastructure: Split the files into subdirectories.

[mLib] / sel / selbuf.c

diff --git a/sel/selbuf.c b/sel/selbuf.c
new file mode 100644 (file)
index 0000000..b572f4b
--- /dev/null
+++ b/sel/selbuf.c
@@ -0,0 +1,169 @@
+/* -*-c-*-
+ *
+ * Line-buffering select handler
+ *
+ * (c) 1999 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of the mLib utilities library.
+ *
+ * mLib is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * mLib is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with mLib; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <unistd.h>
+
+#include "lbuf.h"
+#include "sel.h"
+#include "selbuf.h"
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @selbuf_enable@ --- *
+ *
+ * Arguments:  @selbuf *b@ = pointer to buffer block
+ *
+ * Returns:    ---
+ *
+ * Use:                Enables a buffer for reading, and emits any queued lines
+ *             to the buffer's owner.
+ */
+
+void selbuf_enable(selbuf *b)
+{
+  if (!(b->b.f & LBUF_ENABLE)) {
+    b->b.f |= LBUF_ENABLE;
+    sel_addfile(&b->reader);
+    lbuf_flush(&b->b, 0, 0);
+  }
+}
+
+/* --- @selbuf_disable@ --- *
+ *
+ * Arguments:  @selbuf *b@ = pointer to a buffer block
+ *
+ * Returns:    ---
+ *
+ * Use:                Disables a buffer.  It won't be read from until it's
+ *             enabled again.
+ */
+
+void selbuf_disable(selbuf *b)
+{
+  if (b->b.f & LBUF_ENABLE) {
+    b->b.f &= ~LBUF_ENABLE;
+    sel_rmfile(&b->reader);
+  }
+}
+
+/* --- @selbuf_read@ --- *
+ *
+ * Arguments:  @int fd@ = file descriptor to read from
+ *             @int mode@ = what we can do to the file
+ *             @void *vp@ = pointer to buffer context
+ *
+ * Returns:    ---
+ *
+ * Use:                Acts on the result of a @select@ call.
+ */
+
+static void selbuf_read(int fd, unsigned mode, void *vp)
+{
+  selbuf *b = vp;
+  char *p;
+  size_t sz;
+  int n;
+
+  sz = lbuf_free(&b->b, &p);
+  n = read(fd, p, sz);
+  if (n == 0)
+    lbuf_close(&b->b);
+  else if (n > 0)
+    lbuf_flush(&b->b, p, n);
+  else switch (errno) {
+    case EINTR:
+    case EAGAIN:
+#if EAGAIN != EWOULDBLOCK
+    case EWOULDBLOCK:
+#endif
+      return;
+    default:
+      lbuf_close(&b->b);
+  }
+}
+
+/* --- @selbuf_setsize@ --- *
+ *
+ * Arguments:  @selbuf *b@ = pointer to buffer block
+ *             @size_t sz@ = size of buffer
+ *
+ * Returns:    ---
+ *
+ * Use:                Sets the size of the buffer used for reading lines.
+ */
+
+void selbuf_setsize(selbuf *b, size_t sz)
+{
+  lbuf_setsize(&b->b, sz);
+}
+
+/* --- @selbuf_init@ --- *
+ *
+ * Arguments:  @selbuf *b@ = pointer to buffer block
+ *             @sel_state *s@ = pointer to select state to attach to
+ *             @int fd@ = file descriptor to listen to
+ *             @lbuf_func *func@ = function to call
+ *             @void *p@ = argument for function
+ *
+ * Returns:    ---
+ *
+ * Use:                Initializes a buffer block.
+ */
+
+void selbuf_init(selbuf *b, sel_state *s, int fd, lbuf_func *func, void *p)
+{
+  lbuf_init(&b->b, func, p);
+  b->b.f &= ~LBUF_ENABLE;
+  sel_initfile(s, &b->reader, fd, SEL_READ, selbuf_read, b);
+  selbuf_enable(b);
+}
+
+/* --- @selbuf_destroy@ --- *
+ *
+ * Arguments:  @selbuf *b@ = pointer to buffer block
+ *
+ * Returns:    ---
+ *
+ * Use:                Deallocates a line buffer and frees any resources it owned.
+ */
+
+void selbuf_destroy(selbuf *b)
+{
+  selbuf_disable(b);
+  lbuf_destroy(&b->b);
+}
+
+/*----- That's all, folks -------------------------------------------------*/