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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/fopen.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/fopen.c')
-rw-r--r--lib/fopen.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/lib/fopen.c b/lib/fopen.c
new file mode 100644
index 0000000..a3128fa
--- /dev/null
+++ b/lib/fopen.c
@@ -0,0 +1,107 @@
+/* Open a stream to a file.
+ 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/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2007. */
+
+/* If the user's config.h happens to include <stdio.h>, let it include only
+ the system's <stdio.h> here, so that orig_fopen doesn't recurse to
+ rpl_fopen. */
+#define __need_FILE
+#include <config.h>
+
+/* Get the original definition of fopen. It might be defined as a macro. */
+#include <stdio.h>
+#undef __need_FILE
+
+static FILE *
+orig_fopen (const char *filename, const char *mode)
+{
+ return fopen (filename, mode);
+}
+
+/* Specification. */
+/* Write "stdio.h" here, not <stdio.h>, otherwise OSF/1 5.1 DTK cc eliminates
+ this include because of the preliminary #include <stdio.h> above. */
+#include "stdio.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+FILE *
+rpl_fopen (const char *filename, const char *mode)
+{
+#if defined _WIN32 && ! defined __CYGWIN__
+ if (strcmp (filename, "/dev/null") == 0)
+ filename = "NUL";
+#endif
+
+#if FOPEN_TRAILING_SLASH_BUG
+ /* Fail if the mode requires write access and the filename ends in a slash,
+ as POSIX says such a filename must name a directory
+ <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13>:
+ "A pathname that contains at least one non-<slash> character and that
+ ends with one or more trailing <slash> characters shall not be resolved
+ successfully unless the last pathname component before the trailing
+ <slash> characters names an existing directory"
+ If the named file already exists as a directory, then if a mode that
+ requires write access is specified, fopen() must fail because POSIX
+ <https://pubs.opengroup.org/onlinepubs/9699919799/functions/fopen.html>
+ says that it fails with errno = EISDIR in this case.
+ If the named file does not exist or does not name a directory, then
+ fopen() must fail since the file does not contain a '.' directory. */
+ {
+ size_t len = strlen (filename);
+ if (len > 0 && filename[len - 1] == '/')
+ {
+ int fd;
+ struct stat statbuf;
+ FILE *fp;
+
+ if (mode[0] == 'w' || mode[0] == 'a')
+ {
+ errno = EISDIR;
+ return NULL;
+ }
+
+ fd = open (filename, O_RDONLY);
+ if (fd < 0)
+ return NULL;
+
+ if (fstat (fd, &statbuf) >= 0 && !S_ISDIR (statbuf.st_mode))
+ {
+ close (fd);
+ errno = ENOTDIR;
+ return NULL;
+ }
+
+ fp = fdopen (fd, mode);
+ if (fp == NULL)
+ {
+ int saved_errno = errno;
+ close (fd);
+ errno = saved_errno;
+ }
+ return fp;
+ }
+ }
+# endif
+
+ return orig_fopen (filename, mode);
+}