--- embedaddon/libiconv/srclib/areadlink.c 2012/02/21 22:57:48 1.1
+++ embedaddon/libiconv/srclib/areadlink.c 2021/03/17 13:38:46 1.1.1.3
@@ -1,7 +1,7 @@
/* areadlink.c -- readlink wrapper to return the link name in malloc'd storage
Unlike xreadlink and xreadlink_with_size, don't ever call exit.
- Copyright (C) 2001, 2003-2007 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2003-2007, 2009-2019 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
@@ -14,7 +14,7 @@
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 . */
+ along with this program. If not, see . */
/* Written by Jim Meyering
and Bruno Haible . */
@@ -24,97 +24,33 @@
/* Specification. */
#include "areadlink.h"
-#include
-#include
-#include
-#include
+#include "careadlinkat.h"
+
#include
#include
-#ifndef SIZE_MAX
-# define SIZE_MAX ((size_t) -1)
-#endif
-#ifndef SSIZE_MAX
-# define SSIZE_MAX ((ssize_t) (SIZE_MAX / 2))
-#endif
+/* Get the symbolic link value of FILENAME and put it into BUFFER, with
+ size BUFFER_SIZE. This function acts like readlink but has
+ readlinkat's signature. */
+static ssize_t
+careadlinkatcwd (int fd, char const *filename, char *buffer,
+ size_t buffer_size)
+{
+ /* FD must be AT_FDCWD here, otherwise the caller is using this
+ function in contexts it was not meant for. */
+ if (fd != AT_FDCWD)
+ abort ();
+ return readlink (filename, buffer, buffer_size);
+}
/* Call readlink to get the symbolic link value of FILENAME.
Return a pointer to that NUL-terminated string in malloc'd storage.
If readlink fails, return NULL and set errno.
- If realloc fails, or if the link value is longer than SIZE_MAX :-),
+ If allocation fails, or if the link value is longer than SIZE_MAX :-),
return NULL and set errno to ENOMEM. */
char *
areadlink (char const *filename)
{
- /* The initial buffer size for the link value. A power of 2
- detects arithmetic overflow earlier, but is not required. */
-#define INITIAL_BUF_SIZE 1024
-
- /* Allocate the initial buffer on the stack. This way, in the common
- case of a symlink of small size, we get away with a single small malloc()
- instead of a big malloc() followed by a shrinking realloc(). */
- char initial_buf[INITIAL_BUF_SIZE];
-
- char *buffer = initial_buf;
- size_t buf_size = sizeof (initial_buf);
-
- while (1)
- {
- /* Attempt to read the link into the current buffer. */
- ssize_t link_length = readlink (filename, buffer, buf_size);
-
- /* On AIX 5L v5.3 and HP-UX 11i v2 04/09, readlink returns -1
- with errno == ERANGE if the buffer is too small. */
- if (link_length < 0 && errno != ERANGE)
- {
- if (buffer != initial_buf)
- {
- int saved_errno = errno;
- free (buffer);
- errno = saved_errno;
- }
- return NULL;
- }
-
- if ((size_t) link_length < buf_size)
- {
- buffer[link_length++] = '\0';
-
- /* Return it in a chunk of memory as small as possible. */
- if (buffer == initial_buf)
- {
- buffer = (char *) malloc (link_length);
- if (buffer == NULL)
- /* errno is ENOMEM. */
- return NULL;
- memcpy (buffer, initial_buf, link_length);
- }
- else
- {
- /* Shrink buffer before returning it. */
- if ((size_t) link_length < buf_size)
- {
- char *smaller_buffer = (char *) realloc (buffer, link_length);
-
- if (smaller_buffer != NULL)
- buffer = smaller_buffer;
- }
- }
- return buffer;
- }
-
- if (buffer != initial_buf)
- free (buffer);
- buf_size *= 2;
- if (SSIZE_MAX < buf_size || (SIZE_MAX / 2 < SSIZE_MAX && buf_size == 0))
- {
- errno = ENOMEM;
- return NULL;
- }
- buffer = (char *) malloc (buf_size);
- if (buffer == NULL)
- /* errno is ENOMEM. */
- return NULL;
- }
+ return careadlinkat (AT_FDCWD, filename, NULL, 0, NULL, careadlinkatcwd);
}