Use *_MAX to remove need for configure-time type size checks

3 files changed, 8 insertions, 126 deletions

diff --git a/configure.ac b/configure.ac
index 1aaf55b..1d8669f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -260,11 +260,6 @@ PKG_CHECK_MODULES(READLINE, [readline], [have_readline="yes"],
 AM_CONDITIONAL([WITH_READLINE], [test "x$have_readline" = "xyes"])
 
 ##### additional checks #####
-AX_COMPILE_CHECK_SIZEOF(size_t)
-AX_COMPILE_CHECK_SIZEOF(int)
-AX_COMPILE_CHECK_SIZEOF(long)
-AX_COMPILE_CHECK_SIZEOF(long long)
-
 AC_CHECK_HEADERS([sys/xattr.h], [], [])
 AC_CHECK_HEADERS([sys/sysinfo.h], [], [])
 AC_CHECK_HEADERS([alloca.h], [], [])
diff --git a/include/compat.h b/include/compat.h
index 8a2522e..e82f2ad 100644
--- a/include/compat.h
+++ b/include/compat.h
@@ -10,17 +10,19 @@
 #include "sqfs/predef.h"
 #include "config.h"
 
+#include <limits.h>
+
 #if defined(__GNUC__) && __GNUC__ >= 5
 #	define SZ_ADD_OV __builtin_add_overflow
 #	define SZ_MUL_OV __builtin_mul_overflow
 #elif defined(__clang__) && defined(__GNUC__) && __GNUC__ < 5
-#	if SIZEOF_SIZE_T <= SIZEOF_INT
+#	if SIZE_MAX <= UINT_MAX
 #		define SZ_ADD_OV __builtin_uadd_overflow
 #		define SZ_MUL_OV __builtin_umul_overflow
-#	elif SIZEOF_SIZE_T == SIZEOF_LONG
+#	elif SIZE_MAX == ULONG_MAX
 #		define SZ_ADD_OV __builtin_uaddl_overflow
 #		define SZ_MUL_OV __builtin_umull_overflow
-#	elif SIZEOF_SIZE_T == SIZEOF_LONG_LONG
+#	elif SIZE_MAX == ULLONG_MAX
 #		define SZ_ADD_OV __builtin_uaddll_overflow
 #		define SZ_MUL_OV __builtin_umulll_overflow
 #	else
@@ -51,11 +53,11 @@ static inline int _sz_mul_overflow(size_t a, size_t b, size_t *res)
 #	define PRI_U32 "%" PRIu32
 #endif
 
-#if SIZEOF_SIZE_T <= SIZEOF_INT
+#if SIZE_MAX <= UINT_MAX
 #	define PRI_SZ "%u"
-#elif SIZEOF_SIZE_T == SIZEOF_LONG
+#elif SIZE_MAX == ULONG_MAX
 #	define PRI_SZ "%lu"
-#elif defined(_WIN32) && SIZEOF_SIZE_T == 8
+#elif defined(_WIN32) && SIZE_MAX == UINT64_MAX
 #	define PRI_SZ "%I64u"
 #else
 #	error Cannot figure out propper printf specifier for size_t
diff --git a/m4/ax_compile_check_sizeof.m4 b/m4/ax_compile_check_sizeof.m4
deleted file mode 100644
index f834df6..0000000
--- a/m4/ax_compile_check_sizeof.m4
+++ /dev/null
@@ -1,115 +0,0 @@
-# ============================================================================
-#  https://www.gnu.org/software/autoconf-archive/ax_compile_check_sizeof.html
-# ============================================================================
-#
-# SYNOPSIS
-#
-#   AX_COMPILE_CHECK_SIZEOF(TYPE [, HEADERS [, EXTRA_SIZES...]])
-#
-# DESCRIPTION
-#
-#   This macro checks for the size of TYPE using compile checks, not run
-#   checks. You can supply extra HEADERS to look into. the check will cycle
-#   through 1 2 4 8 16 and any EXTRA_SIZES the user supplies. If a match is
-#   found, it will #define SIZEOF_`TYPE' to that value. Otherwise it will
-#   emit a configure time error indicating the size of the type could not be
-#   determined.
-#
-#   The trick is that C will not allow duplicate case labels. While this is
-#   valid C code:
-#
-#     switch (0) case 0: case 1:;
-#
-#   The following is not:
-#
-#     switch (0) case 0: case 0:;
-#
-#   Thus, the AC_COMPILE_IFELSE will fail if the currently tried size does
-#   not match.
-#
-#   Here is an example skeleton configure.in script, demonstrating the
-#   macro's usage:
-#
-#     AC_PROG_CC
-#     AC_CHECK_HEADERS(stddef.h unistd.h)
-#     AC_TYPE_SIZE_T
-#     AC_CHECK_TYPE(ssize_t, int)
-#
-#     headers='#ifdef HAVE_STDDEF_H
-#     #include <stddef.h>
-#     #endif
-#     #ifdef HAVE_UNISTD_H
-#     #include <unistd.h>
-#     #endif
-#     '
-#
-#     AX_COMPILE_CHECK_SIZEOF(char)
-#     AX_COMPILE_CHECK_SIZEOF(short)
-#     AX_COMPILE_CHECK_SIZEOF(int)
-#     AX_COMPILE_CHECK_SIZEOF(long)
-#     AX_COMPILE_CHECK_SIZEOF(unsigned char *)
-#     AX_COMPILE_CHECK_SIZEOF(void *)
-#     AX_COMPILE_CHECK_SIZEOF(size_t, $headers)
-#     AX_COMPILE_CHECK_SIZEOF(ssize_t, $headers)
-#     AX_COMPILE_CHECK_SIZEOF(ptrdiff_t, $headers)
-#     AX_COMPILE_CHECK_SIZEOF(off_t, $headers)
-#
-# LICENSE
-#
-#   Copyright (c) 2008 Kaveh Ghazi <ghazi@caip.rutgers.edu>
-#   Copyright (c) 2017 Reini Urban <rurban@cpan.org>
-#
-#   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/>.
-#
-#   As a special exception, the respective Autoconf Macro's copyright owner
-#   gives unlimited permission to copy, distribute and modify the configure
-#   scripts that are the output of Autoconf when processing the Macro. You
-#   need not follow the terms of the GNU General Public License when using
-#   or distributing such scripts, even though portions of the text of the
-#   Macro appear in them. The GNU General Public License (GPL) does govern
-#   all other use of the material that constitutes the Autoconf Macro.
-#
-#   This special exception to the GPL applies to versions of the Autoconf
-#   Macro released by the Autoconf Archive. When you make and distribute a
-#   modified version of the Autoconf Macro, you may extend this special
-#   exception to the GPL to apply to your modified version as well.
-
-#serial 8
-
-AU_ALIAS([AC_COMPILE_CHECK_SIZEOF], [AX_COMPILE_CHECK_SIZEOF])
-AC_DEFUN([AX_COMPILE_CHECK_SIZEOF],
-[changequote(<<, >>)dnl
-dnl The name to #define.
-define(<<AC_TYPE_NAME>>, translit(sizeof_$1, [a-z *], [A-Z_P]))dnl
-dnl The cache variable name.
-define(<<AC_CV_NAME>>, translit(ac_cv_sizeof_$1, [ *], [_p]))dnl
-changequote([, ])dnl
-AC_MSG_CHECKING(size of $1)
-AC_CACHE_VAL(AC_CV_NAME,
-[for ac_size in 4 8 1 2 16 $3 ; do # List sizes in rough order of prevalence.
-  AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-#include <sys/types.h>
-$2
-]], [[switch (0) case 0: case (sizeof ($1) == $ac_size):;]])], [AC_CV_NAME=$ac_size])
-  if test x$AC_CV_NAME != x ; then break; fi
-done
-])
-if test x$AC_CV_NAME = x ; then
-  AC_MSG_ERROR([cannot determine a size for $1])
-fi
-AC_MSG_RESULT($AC_CV_NAME)
-AC_DEFINE_UNQUOTED(AC_TYPE_NAME, $AC_CV_NAME, [The number of bytes in type $1])
-undefine([AC_TYPE_NAME])dnl
-undefine([AC_CV_NAME])dnl
-])