buf: Fix two embarassing bugs found while writing Lisp bindings.

[mLib] / selbuf.c

diff --git a/selbuf.c b/selbuf.c
index 0f07dfc056dc99934301323bd433c59ee7050ce2..6fe97eef1c7407af0cb106d4832ed1c25eba2822 100644 (file)
--- a/selbuf.c
+++ b/selbuf.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: selbuf.c,v 1.1 1999/05/14 21:01:15 mdw Exp $
+ * $Id: selbuf.c,v 1.6 2004/04/08 01:36:13 mdw Exp $
  *
  * Line-buffering select handler
  *
@@ -27,14 +27,6 @@
  * MA 02111-1307, USA.
  */
 
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: selbuf.c,v $
- * Revision 1.1  1999/05/14 21:01:15  mdw
- * Integrated `select' handling bits from the background resolver project.
- *
- */
-
 /*----- Header files ------------------------------------------------------*/
 
 #include <errno.h>
@@ -64,8 +56,8 @@
 
 void selbuf_enable(selbuf *b)
 {
-  if (!(b->b.f & lbuf_enable)) {
-    b->b.f |= lbuf_enable;
+  if (!(b->b.f & LBUF_ENABLE)) {
+    b->b.f |= LBUF_ENABLE;
     sel_addfile(&b->reader);
     lbuf_flush(&b->b, 0, 0);
   }
@@ -83,8 +75,8 @@ void selbuf_enable(selbuf *b)
 
 void selbuf_disable(selbuf *b)
 {
-  if (b->b.f & lbuf_enable) {
-    b->b.f &= ~lbuf_enable;
+  if (b->b.f & LBUF_ENABLE) {
+    b->b.f &= ~LBUF_ENABLE;
     sel_rmfile(&b->reader);
   }
 }
@@ -108,23 +100,36 @@ static void selbuf_read(int fd, unsigned mode, void *vp)
   int n;
 
   sz = lbuf_free(&b->b, &p);
-again:
   n = read(fd, p, sz);
-  if (n <= 0) {
-    switch (errno) {
-      case EINTR:
-       goto again;
-      case EAGAIN:
+  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:
+    case EWOULDBLOCK:
 #endif
-       return;
-      default:
-       lbuf_close(&b->b);
-    }
+      return;
+    default:
+      lbuf_close(&b->b);
   }
-  else
-    lbuf_flush(&b->b, p, n);
+}
+
+/* --- @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@ --- *
@@ -132,7 +137,7 @@ again:
  * Arguments:  @selbuf *b@ = pointer to buffer block
  *             @sel_state *s@ = pointer to select state to attach to
  *             @int fd@ = file descriptor to listen to
- *             @void (*func)(char *s, void *p)@ = function to call
+ *             @lbuf_func *func@ = function to call
  *             @void *p@ = argument for function
  *
  * Returns:    ---
@@ -140,16 +145,27 @@ again:
  * Use:                Initializes a buffer block.
  */
 
-void selbuf_init(selbuf *b,
-                sel_state *s,
-                int fd,
-                void (*func)(char */*s*/, void */*p*/),
-                void *p)
+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;
+  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 -------------------------------------------------*/