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-rw-r--r--libio/oldfmemopen.c275
1 files changed, 0 insertions, 275 deletions
diff --git a/libio/oldfmemopen.c b/libio/oldfmemopen.c
deleted file mode 100644
index c2fef8d942..0000000000
--- a/libio/oldfmemopen.c
+++ /dev/null
@@ -1,275 +0,0 @@
-/* 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
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