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-rw-r--r--lib/strerror.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/lib/strerror.c b/lib/strerror.c
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+/* strerror.c --- POSIX compatible system error routine
+
+ Copyright (C) 2007-2022 Free Software Foundation, Inc.
+
+ This file 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.
+
+ This file 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 this program. If not, see <https://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include <string.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "intprops.h"
+#include "strerror-override.h"
+#include "verify.h"
+
+/* Use the system functions, not the gnulib overrides in this file. */
+#undef sprintf
+
+char *
+strerror (int n)
+#undef strerror
+{
+ static char buf[STACKBUF_LEN];
+ size_t len;
+
+ /* Cast away const, due to the historical signature of strerror;
+ callers should not be modifying the string. */
+ const char *msg = strerror_override (n);
+ if (msg)
+ return (char *) msg;
+
+ msg = strerror (n);
+
+ /* Our strerror_r implementation might use the system's strerror
+ buffer, so all other clients of strerror have to see the error
+ copied into a buffer that we manage. This is not thread-safe,
+ even if the system strerror is, but portable programs shouldn't
+ be using strerror if they care about thread-safety. */
+ if (!msg || !*msg)
+ {
+ static char const fmt[] = "Unknown error %d";
+ verify (sizeof buf >= sizeof (fmt) + INT_STRLEN_BOUND (n));
+ sprintf (buf, fmt, n);
+ errno = EINVAL;
+ return buf;
+ }
+
+ /* Fix STACKBUF_LEN if this ever aborts. */
+ len = strlen (msg);
+ if (sizeof buf <= len)
+ abort ();
+
+ memcpy (buf, msg, len + 1);
+ return buf;
+}