--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/substdo.c	Thu Nov 01 14:46:11 2007 +0100
@@ -0,0 +1,108 @@
+#include "substdio.h"
+#include "str.h"
+#include "byte.h"
+#include "error.h"
+
+static int allwrite(op,fd,buf,len)
+register int (*op)();
+register int fd;
+register char *buf;
+register int len;
+{
+  register int w;
+
+  while (len) {
+    w = op(fd,buf,len);
+    if (w == -1) {
+      if (errno == error_intr) continue;
+      return -1; /* note that some data may have been written */
+    }
+    if (w == 0) ; /* luser's fault */
+    buf += w;
+    len -= w;
+  }
+  return 0;
+}
+
+int substdio_flush(s)
+register substdio *s;
+{
+  register int p;
+ 
+  p = s->p;
+  if (!p) return 0;
+  s->p = 0;
+  return allwrite(s->op,s->fd,s->x,p);
+}
+
+int substdio_bput(s,buf,len)
+register substdio *s;
+register char *buf;
+register int len;
+{
+  register int n;
+ 
+  while (len > (n = s->n - s->p)) {
+    byte_copy(s->x + s->p,n,buf); s->p += n; buf += n; len -= n;
+    if (substdio_flush(s) == -1) return -1;
+  }
+  /* now len <= s->n - s->p */
+  byte_copy(s->x + s->p,len,buf);
+  s->p += len;
+  return 0;
+}
+
+int substdio_put(s,buf,len)
+register substdio *s;
+register char *buf;
+register int len;
+{
+  register int n;
+ 
+  n = s->n;
+  if (len > n - s->p) {
+    if (substdio_flush(s) == -1) return -1;
+    /* now s->p == 0 */
+    if (n < SUBSTDIO_OUTSIZE) n = SUBSTDIO_OUTSIZE;
+    while (len > s->n) {
+      if (n > len) n = len;
+      if (allwrite(s->op,s->fd,buf,n) == -1) return -1;
+      buf += n;
+      len -= n;
+    }
+  }
+  /* now len <= s->n - s->p */
+  byte_copy(s->x + s->p,len,buf);
+  s->p += len;
+  return 0;
+}
+
+int substdio_putflush(s,buf,len)
+register substdio *s;
+register char *buf;
+register int len;
+{
+  if (substdio_flush(s) == -1) return -1;
+  return allwrite(s->op,s->fd,buf,len);
+}
+
+int substdio_bputs(s,buf)
+register substdio *s;
+register char *buf;
+{
+  return substdio_bput(s,buf,str_len(buf));
+}
+
+int substdio_puts(s,buf)
+register substdio *s;
+register char *buf;
+{
+  return substdio_put(s,buf,str_len(buf));
+}
+
+int substdio_putsflush(s,buf)
+register substdio *s;
+register char *buf;
+{
+  return substdio_putflush(s,buf,str_len(buf));
+}