Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 275 insertions, 0 deletions

diff --git a/REORG.TODO/libio/oldfmemopen.c b/REORG.TODO/libio/oldfmemopen.c
new file mode 100644
index 0000000000..c2fef8d942
--- /dev/null
+++ b/REORG.TODO/libio/oldfmemopen.c
@@ -0,0 +1,275 @@
+/* Fmemopen implementation.
+   Copyright (C) 2000-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Hanno Mueller, kontakt@hanno.de, 2000.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/*
+ * fmemopen() - "my" version of a string stream
+ * Hanno Mueller, kontakt@hanno.de
+ *
+ *
+ * I needed fmemopen() for an application that I currently work on,
+ * but couldn't find it in libio. The following snippet of code is an
+ * attempt to implement what glibc's documentation describes.
+ *
+ *
+ *
+ * I already see some potential problems:
+ *
+ * - I never used the "original" fmemopen(). I am sure that "my"
+ *   fmemopen() behaves differently than the original version.
+ *
+ * - The documentation doesn't say wether a string stream allows
+ *   seeks. I checked the old fmemopen implementation in glibc's stdio
+ *   directory, wasn't quite able to see what is going on in that
+ *   source, but as far as I understand there was no seek there. For
+ *   my application, I needed fseek() and ftell(), so it's here.
+ *
+ * - "append" mode and fseek(p, SEEK_END) have two different ideas
+ *   about the "end" of the stream.
+ *
+ *   As described in the documentation, when opening the file in
+ *   "append" mode, the position pointer will be set to the first null
+ *   character of the string buffer (yet the buffer may already
+ *   contain more data). For fseek(), the last byte of the buffer is
+ *   used as the end of the stream.
+ *
+ * - It is unclear to me what the documentation tries to say when it
+ *   explains what happens when you use fmemopen with a NULL
+ *   buffer.
+ *
+ *   Quote: "fmemopen [then] allocates an array SIZE bytes long. This
+ *   is really only useful if you are going to write things to the
+ *   buffer and then read them back in again."
+ *
+ *   What does that mean if the original fmemopen() did not allow
+ *   seeking? How do you read what you just wrote without seeking back
+ *   to the beginning of the stream?
+ *
+ * - I think there should be a second version of fmemopen() that does
+ *   not add null characters for each write. (At least in my
+ *   application, I am not actually using strings but binary data and
+ *   so I don't need the stream to add null characters on its own.)
+ */
+
+#include "libioP.h"
+
+#if SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_22)
+
+#include <errno.h>
+#include <libio.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/types.h>
+
+
+typedef struct fmemopen_cookie_struct fmemopen_cookie_t;
+struct fmemopen_cookie_struct
+{
+  char *buffer;
+  int mybuffer;
+  int binmode;
+  size_t size;
+  _IO_off64_t pos;
+  size_t maxpos;
+};
+
+
+static ssize_t
+fmemopen_read (void *cookie, char *b, size_t s)
+{
+  fmemopen_cookie_t *c;
+
+  c = (fmemopen_cookie_t *) cookie;
+
+  if (c->pos + s > c->size)
+    {
+      if ((size_t) c->pos == c->size)
+	return 0;
+      s = c->size - c->pos;
+    }
+
+  memcpy (b, &(c->buffer[c->pos]), s);
+
+  c->pos += s;
+  if ((size_t) c->pos > c->maxpos)
+    c->maxpos = c->pos;
+
+  return s;
+}
+
+
+static ssize_t
+fmemopen_write (void *cookie, const char *b, size_t s)
+{
+  fmemopen_cookie_t *c;
+  int addnullc;
+
+  c = (fmemopen_cookie_t *) cookie;
+
+  addnullc = c->binmode == 0 && (s == 0 || b[s - 1] != '\0');
+
+  if (c->pos + s + addnullc > c->size)
+    {
+      if ((size_t) (c->pos + addnullc) >= c->size)
+	{
+	  __set_errno (ENOSPC);
+	  return 0;
+	}
+      s = c->size - c->pos - addnullc;
+    }
+
+  memcpy (&(c->buffer[c->pos]), b, s);
+
+  c->pos += s;
+  if ((size_t) c->pos > c->maxpos)
+    {
+      c->maxpos = c->pos;
+      if (addnullc)
+	c->buffer[c->maxpos] = '\0';
+    }
+
+  return s;
+}
+
+
+static int
+fmemopen_seek (void *cookie, _IO_off64_t *p, int w)
+{
+  _IO_off64_t np;
+  fmemopen_cookie_t *c;
+
+  c = (fmemopen_cookie_t *) cookie;
+
+  switch (w)
+    {
+    case SEEK_SET:
+      np = *p;
+      break;
+
+    case SEEK_CUR:
+      np = c->pos + *p;
+      break;
+
+    case SEEK_END:
+      np = (c->binmode ? c->size : c->maxpos) - *p;
+      break;
+
+    default:
+      return -1;
+    }
+
+  if (np < 0 || (size_t) np > c->size)
+    return -1;
+
+  *p = c->pos = np;
+
+  return 0;
+}
+
+
+static int
+fmemopen_close (void *cookie)
+{
+  fmemopen_cookie_t *c;
+
+  c = (fmemopen_cookie_t *) cookie;
+
+  if (c->mybuffer)
+    free (c->buffer);
+  free (c);
+
+  return 0;
+}
+
+
+FILE *
+__old_fmemopen (void *buf, size_t len, const char *mode)
+{
+  cookie_io_functions_t iof;
+  fmemopen_cookie_t *c;
+  FILE *result;
+
+  if (__glibc_unlikely (len == 0))
+    {
+    einval:
+      __set_errno (EINVAL);
+      return NULL;
+    }
+
+  c = (fmemopen_cookie_t *) malloc (sizeof (fmemopen_cookie_t));
+  if (c == NULL)
+    return NULL;
+
+  c->mybuffer = (buf == NULL);
+
+  if (c->mybuffer)
+    {
+      c->buffer = (char *) malloc (len);
+      if (c->buffer == NULL)
+	{
+	  free (c);
+	  return NULL;
+	}
+      c->buffer[0] = '\0';
+      c->maxpos = 0;
+    }
+  else
+    {
+      if (__glibc_unlikely ((uintptr_t) len > -(uintptr_t) buf))
+	{
+	  free (c);
+	  goto einval;
+	}
+
+      c->buffer = buf;
+
+      if (mode[0] == 'w')
+	c->buffer[0] = '\0';
+
+      c->maxpos = strnlen (c->buffer, len);
+    }
+
+  c->size = len;
+
+  if (mode[0] == 'a')
+    c->pos = c->maxpos;
+  else
+    c->pos = 0;
+
+  c->binmode = mode[0] != '\0' && mode[1] == 'b';
+
+  iof.read = fmemopen_read;
+  iof.write = fmemopen_write;
+  iof.seek = fmemopen_seek;
+  iof.close = fmemopen_close;
+
+  result = _IO_fopencookie (c, mode, iof);
+  if (__glibc_unlikely (result == NULL))
+    {
+      if (c->mybuffer)
+	free (c->buffer);
+
+      free (c);
+    }
+
+  return result;
+}
+compat_symbol (libc, __old_fmemopen, fmemopen, GLIBC_2_2);
+#endif