Introduce a configure time check for the presence of `error.h`. In the
case that `error.h` is not available, we can fall back to `err.h`.
Although `err.h` is not a C standard header (it is a BSD extension),
many libc implementations provide. If there are targets which do not
provide an implementation of `err.h`, it would be possible to further
extend the implementation to be more portable.
This partially resolves bug #21008.
Signed-off-by: Saleem Abdulrasool <abdul...@google.com>
---
configure.ac | 3 +++
lib/ChangeLog | 7 +++++++
lib/Makefile.am | 2 +-
lib/error.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
lib/system.h | 13 ++++++++++++-
5 files changed, 72 insertions(+), 2 deletions(-)
create mode 100644 lib/error.c
diff --git a/configure.ac b/configure.ac
index 7caff2c5..177bb1a2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -431,6 +431,9 @@ AC_CHECK_DECLS([reallocarray],[],[],
AC_CHECK_FUNCS([process_vm_readv])
+AC_CHECK_HEADERS([error.h])
+AC_CHECK_HEADERS([err.h])
+
old_CFLAGS="$CFLAGS"
CFLAGS="$CFLAGS -D_GNU_SOURCE"
AC_FUNC_STRERROR_R()
diff --git a/lib/ChangeLog b/lib/ChangeLog
index a95f8041..101a4e6f 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,10 @@
+2021-08-20 Saleem Abdulrasool <abdul...@google.com>
+
+ * error.c: New file, adds error_number_count and error fallbacks.
+ * system.h: Declare error_number_count and error fallbacks for when
+ error.h is unavailable.
+ * Makefile.am (libeu_a_SOURCES): add error.c.
+
2021-08-20 Saleem Abdulrasool <abdul...@google.com>
* fixedsizehash.h: Remove sys/cdefs.h include. Unconditionally
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 97bf7329..766fbcd7 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -35,7 +35,7 @@ noinst_LIBRARIES = libeu.a
libeu_a_SOURCES = xstrdup.c xstrndup.c xmalloc.c next_prime.c \
crc32.c crc32_file.c \
- color.c printversion.c
+ color.c error.c printversion.c
noinst_HEADERS = fixedsizehash.h libeu.h system.h dynamicsizehash.h list.h \
eu-config.h color.h printversion.h bpf.h \
diff --git a/lib/error.c b/lib/error.c
new file mode 100644
index 00000000..b0264efb
--- /dev/null
+++ b/lib/error.c
@@ -0,0 +1,49 @@
+/* Definitions for error handling fallback functions.
+ Copyright (C) 2021 Google, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * the GNU General Public License as published by the Free
+ Software Foundation; either version 2 of the License, or (at
+ your option) any later version
+
+ or both in parallel, as here.
+
+ elfutils 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#if !defined(HAVE_ERROR_H) && defined(HAVE_ERR_H)
+#include <stdarg.h>
+#include <stdlib.h>
+#include <err.h>
+
+unsigned int error_message_count = 0;
+
+void error(int status, int errnum, const char *format, ...) {
+ va_list argp;
+
+ va_start(argp, format);
+ verr(status, format, argp);
+ va_end(argp);
+
+ if (status)
+ exit(status);
+ ++error_message_count;
+}
+#endif
diff --git a/lib/system.h b/lib/system.h
index 58d9deee..edbc8488 100644
--- a/lib/system.h
+++ b/lib/system.h
@@ -29,8 +29,9 @@
#ifndef LIB_SYSTEM_H
#define LIB_SYSTEM_H 1
+#include <config.h>
+
#include <errno.h>
-#include <error.h>
#include <stddef.h>
#include <stdint.h>
#include <sys/param.h>
@@ -38,8 +39,18 @@
#include <byteswap.h>
#include <unistd.h>
#include <string.h>
+#include <stdarg.h>
#include <stdlib.h>
+#if defined(HAVE_ERROR_H)
+#include <error.h>
+#elif defined(HAVE_ERR_H)
+extern int error_message_count;
+void error(int status, int errnum, const char *format, ...);
+#else
+#error "err.h or error.h must be available"
+#endif
+
#if __BYTE_ORDER == __LITTLE_ENDIAN
# define LE32(n) (n)
# define LE64(n) (n)
--
2.33.0.259.gc128427fd7-goog
