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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 17:39:29 +0000
commit8ffec2a3aba6f114784e11f89ef1d57a096ae540 (patch)
treeccebcbad06203e8241a8e7249f8e6c478a3682ea /lib/freadptr.c
parentInitial commit. (diff)
downloadcoreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.tar.xz
coreutils-8ffec2a3aba6f114784e11f89ef1d57a096ae540.zip
Adding upstream version 8.32.upstream/8.32upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/freadptr.c')
-rw-r--r--lib/freadptr.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/lib/freadptr.c b/lib/freadptr.c
new file mode 100644
index 0000000..8972cb1
--- /dev/null
+++ b/lib/freadptr.c
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+/* Retrieve information about a FILE stream.
+ Copyright (C) 2007-2020 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include "freadptr.h"
+
+#include <stdlib.h>
+
+#include "stdio-impl.h"
+
+/* This file is not used on systems that have the __freadptr function,
+ namely musl libc. */
+
+const char *
+freadptr (FILE *fp, size_t *sizep)
+{
+ size_t size;
+
+ /* Keep this code in sync with freadahead! */
+#if defined _IO_EOF_SEEN || defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1
+ /* GNU libc, BeOS, Haiku, Linux libc5 */
+ if (fp->_IO_write_ptr > fp->_IO_write_base)
+ return NULL;
+ size = fp->_IO_read_end - fp->_IO_read_ptr;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return (const char *) fp->_IO_read_ptr;
+#elif defined __sferror || defined __DragonFly__ || defined __ANDROID__
+ /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Minix 3, Android */
+ if ((fp_->_flags & __SWR) != 0 || fp_->_r < 0)
+ return NULL;
+ size = fp_->_r;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return (const char *) fp_->_p;
+#elif defined __EMX__ /* emx+gcc */
+ if ((fp->_flags & _IOWRT) != 0)
+ return NULL;
+ /* Note: fp->_ungetc_count > 0 implies fp->_rcount <= 0,
+ fp->_ungetc_count = 0 implies fp->_rcount >= 0. */
+ if (fp->_rcount <= 0)
+ return NULL;
+ if (!(fp->_ungetc_count == 0))
+ abort ();
+ *sizep = fp->_rcount;
+ return fp->_ptr;
+#elif defined __minix /* Minix */
+ if ((fp_->_flags & _IOWRITING) != 0)
+ return NULL;
+ size = fp_->_count;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return (const char *) fp_->_ptr;
+#elif defined _IOERR /* AIX, HP-UX, IRIX, OSF/1, Solaris, OpenServer, mingw, MSVC, NonStop Kernel, OpenVMS */
+ if ((fp_->_flag & _IOWRT) != 0)
+ return NULL;
+ size = fp_->_cnt;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return (const char *) fp_->_ptr;
+#elif defined __UCLIBC__ /* uClibc */
+# ifdef __STDIO_BUFFERS
+ if (fp->__modeflags & __FLAG_WRITING)
+ return NULL;
+ if (fp->__modeflags & __FLAG_UNGOT)
+ return NULL;
+ size = fp->__bufread - fp->__bufpos;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return (const char *) fp->__bufpos;
+# else
+ return NULL;
+# endif
+#elif defined __QNX__ /* QNX */
+ if ((fp->_Mode & 0x2000 /* _MWRITE */) != 0)
+ return NULL;
+ /* fp->_Buf <= fp->_Next <= fp->_Rend */
+ size = fp->_Rend - fp->_Next;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return (const char *) fp->_Next;
+#elif defined __MINT__ /* Atari FreeMiNT */
+ if (!fp->__mode.__read)
+ return NULL;
+ size = fp->__get_limit - fp->__bufp;
+ if (size == 0)
+ return NULL;
+ *sizep = size;
+ return fp->__bufp;
+#elif defined EPLAN9 /* Plan9 */
+ if (fp->state == 4 /* WR */)
+ return NULL;
+ if (fp->rp >= fp->wp)
+ return NULL;
+ *sizep = fp->wp - fp->rp;
+ return fp->rp;
+#elif defined SLOW_BUT_NO_HACKS /* users can define this */
+ /* This implementation is correct on any ANSI C platform. It is just
+ awfully slow. */
+ return NULL;
+#else
+ #error "Please port gnulib freadptr.c to your platform! Look at the definition of fflush, fread, getc, getc_unlocked on your system, then report this to bug-gnulib."
+#endif
+}