initial import

1 files changed, 128 insertions, 0 deletions

diff --git a/stdio/fread.c b/stdio/fread.c
new file mode 100644
index 0000000000..347e8446e1
--- /dev/null
+++ b/stdio/fread.c
@@ -0,0 +1,128 @@
+/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library 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.
+
+The GNU C Library 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 the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+
+#define	default_func	__default_room_functions.__input
+
+/* Read NMEMB chunks of SIZE bytes each from STREAM into P.  */
+size_t
+DEFUN(fread, (p, size, nmemb, stream),
+      PTR p AND size_t size AND size_t nmemb AND register FILE *stream)
+{
+  register char *ptr = (char *) p;
+  register size_t to_read = size * nmemb;
+  size_t bytes = to_read;
+
+  if (!__validfp(stream) || !stream->__mode.__read)
+    {
+      errno = EINVAL;
+      return 0;
+    }
+  if (feof(stream) || ferror(stream))
+    return 0;
+  if (p == NULL || to_read == 0)
+    return 0;
+
+  if (!stream->__seen || stream->__buffer == NULL || stream->__pushed_back)
+    {
+      /* This stream has never been seen before, or it has a character
+	 pushed back.  Call __fillbf to deal with those cases.  Life will
+	 be simpler after this call.  */
+      int c = __fillbf(stream);
+      if (c == EOF)
+	return 0;
+      *ptr++ = c;
+      if (--to_read == 0)
+	return 1;
+    }
+
+ read_from_buffer:;
+  if (stream->__bufp < stream->__get_limit)
+    {
+      /* First off, empty out the buffer.  */
+      register size_t copy = stream->__get_limit - stream->__bufp;
+      if (copy > to_read)
+	copy = to_read;
+      to_read -= copy;
+      if (copy > 20)
+	memcpy((PTR) ptr, (PTR) stream->__bufp, copy);
+      else
+	{
+	  register size_t i;
+	  for (i = 0; i < copy; ++i)
+	    ptr[i] = stream->__bufp[i];
+	}
+      stream->__bufp += copy;
+      if (to_read == 0)
+	return nmemb;
+      ptr += copy;
+    }
+
+  /* Reading directly into the user's buffer doesn't help when
+     using a user-specified input buffer filling/expanding function,
+     so we don't do it in that case.  */
+  if (to_read >= stream->__bufsize &&
+      stream->__room_funcs.__input == default_func &&
+      stream->__offset == stream->__target)
+    {
+      /* Read directly into the user's buffer.  */
+      if (stream->__io_funcs.__read != NULL)
+	while (to_read > 0)
+	  {
+	    register int count;
+	    count = (*stream->__io_funcs.__read)(stream->__cookie,
+						 ptr, to_read);
+	    if (count > 0)
+	      {
+		to_read -= count;
+		stream->__offset += count;
+		stream->__target += count;
+		ptr += count;
+	      }
+	    else if (count == 0)
+	      {
+		stream->__eof = 1;
+		break;
+	      }
+	    else
+	      {
+		stream->__error = 1;
+		break;
+	      }
+	  }
+      else
+	stream->__eof = 1;
+    }
+  else
+    {
+      int c = __fillbf(stream);
+      if (c == EOF)
+	return (bytes - to_read) / size;
+      *ptr++ = (char) c;
+      --to_read;
+      if (to_read > 0)
+	goto read_from_buffer;
+    }
+
+  return (bytes - to_read) / size;
+}