Add configure script to detect compiler flags and feature test macros

This is the same musl originated configure script as vis uses.

Makefile

@@ -1,45 +1,37 @@
-include config.mk
+-include config.mk
+
+VERSION = 0.6
+
+CFLAGS_STD ?= -std=c99 -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700 -DNDEBUG
+CFLAGS_STD += -DVERSION=\"${VERSION}\"
+
+LDFLAGS_STD ?= -lc -lutil
+
+STRIP ?= strip
 
 SRC = abduco.c
-OBJ = ${SRC:.c=.o}
 
-all: clean options abduco
+all: abduco
-
-options:
-	@echo abduco build options:
-	@echo "CFLAGS   = ${CFLAGS}"
-	@echo "LDFLAGS  = ${LDFLAGS}"
-	@echo "CC       = ${CC}"
 
 config.h:
 	cp config.def.h config.h
 
-.c.o:
+config.mk:
-	@echo CC $<
+	@touch $@
-	@${CC} -c ${CFLAGS} $<
 
-${OBJ}: config.h config.mk
+abduco: config.h config.mk *.c
-
+	${CC} ${CFLAGS} ${CFLAGS_STD} ${CFLAGS_AUTO} ${CFLAGS_EXTRA} ${SRC} ${LDFLAGS} ${LDFLAGS_STD} ${LDFLAGS_AUTO} -o $@
-abduco: ${OBJ}
-	@echo CC -o $@
-	@${CC} -o $@ ${OBJ} ${LDFLAGS}
 
 debug: clean
-	@make CFLAGS='${DEBUG_CFLAGS}'
+	make CFLAGS_EXTRA='${CFLAGS_DEBUG}'
 
 clean:
 	@echo cleaning
-	@rm -f abduco ${OBJ} abduco-${VERSION}.tar.gz
+	@rm -f abduco abduco-*.tar.gz
 
 dist: clean
 	@echo creating dist tarball
-	@mkdir -p abduco-${VERSION}
+	@git archive --prefix=abduco-${VERSION}/ -o abduco-${VERSION}.tar.gz HEAD
-	@cp -R LICENSE Makefile README.md testsuite.sh config.def.h config.mk \
-		${SRC} debug.c client.c server.c forkpty-aix.c forkpty-sunos.c \
-		abduco.1 abduco-${VERSION}
-	@tar -cf abduco-${VERSION}.tar abduco-${VERSION}
-	@gzip abduco-${VERSION}.tar
-	@rm -rf abduco-${VERSION}
 
 install: abduco
 	@echo stripping executable
@@ -59,4 +51,4 @@ uninstall:
 	@echo removing manual page from ${DESTDIR}${MANPREFIX}/man1
 	@rm -f ${DESTDIR}${MANPREFIX}/man1/abduco.1
 
-.PHONY: all options clean dist install uninstall debug
+.PHONY: all clean dist install uninstall debug

README.md

@@ -42,7 +42,7 @@ with sha1sum
 
 compile and install it
 
-    $EDITOR config.mk && make && sudo make install
+    ./configure && make && sudo make install
 
 or use one of the distribution provided binary packages:
 

config.mk

@@ -1,19 +0,0 @@
-# abduco version
-VERSION = 0.6
-
-# Customize below to fit your system
-
-PREFIX ?= /usr/local
-MANPREFIX = ${PREFIX}/share/man
-
-INCS = -I.
-LIBS = -lc -lutil
-
-CPPFLAGS = -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700
-CFLAGS += -std=c99 -pedantic -Wall ${INCS} -DVERSION=\"${VERSION}\" -DNDEBUG ${CPPFLAGS}
-LDFLAGS += ${LIBS}
-
-DEBUG_CFLAGS = ${CFLAGS} -UNDEBUG -O0 -g -ggdb
-
-CC ?= cc
-STRIP ?= strip

configure

@@ -0,0 +1,244 @@
+#!/bin/sh
+# Based on the configure script from musl libc, MIT licensed
+
+usage () {
+cat <<EOF
+Usage: $0 [OPTION]... [VAR=VALUE]...
+
+To assign environment variables (e.g., CC, CFLAGS...), specify them as
+VAR=VALUE.  See below for descriptions of some of the useful variables.
+
+Defaults for the options are specified in brackets.
+
+Configuration:
+  --srcdir=DIR            source directory [detected]
+
+Installation directories:
+  --prefix=PREFIX         main installation prefix [/usr/local]
+  --exec-prefix=EPREFIX   installation prefix for executable files [PREFIX]
+
+Fine tuning of the installation directories:
+  --bindir=DIR            user executables [EPREFIX/bin]
+  --sharedir=DIR          share directories [PREFIX/share]
+  --docdir=DIR            misc. documentation [PREFIX/share/doc]
+  --mandir=DIR            man pages [PREFIX/share/man]
+
+Some influential environment variables:
+  CC                      C compiler command [detected]
+  CFLAGS                  C compiler flags [-Os -pipe ...]
+  LDFLAGS                 Linker flags
+
+Use these variables to override the choices made by configure.
+
+EOF
+exit 0
+}
+
+# Helper functions
+
+quote () {
+tr '\n' ' ' <<EOF | grep '^[-[:alnum:]_=,./:]* $' >/dev/null 2>&1 && { echo "$1" ; return 0 ; }
+$1
+EOF
+printf %s\\n "$1" | sed -e "s/'/'\\\\''/g" -e "1s/^/'/" -e "\$s/\$/'/" -e "s#^'\([-[:alnum:]_,./:]*\)=\(.*\)\$#\1='\2#"
+}
+echo () { printf "%s\n" "$*" ; }
+fail () { echo "$*" ; exit 1 ; }
+fnmatch () { eval "case \"\$2\" in $1) return 0 ;; *) return 1 ;; esac" ; }
+cmdexists () { type "$1" >/dev/null 2>&1 ; }
+trycc () { test -z "$CC" && cmdexists "$1" && CC=$1 ; }
+
+stripdir () {
+while eval "fnmatch '*/' \"\${$1}\"" ; do eval "$1=\${$1%/}" ; done
+}
+
+trycppif () {
+printf "checking preprocessor condition %s... " "$1"
+echo "typedef int x;" > "$tmpc"
+echo "#if $1" >> "$tmpc"
+echo "#error yes" >> "$tmpc"
+echo "#endif" >> "$tmpc"
+if $CC $2 -c -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+printf "false\n"
+return 1
+else
+printf "true\n"
+return 0
+fi
+}
+
+tryflag () {
+printf "checking whether compiler accepts %s... " "$2"
+echo "typedef int x;" > "$tmpc"
+if $CC $CFLAGS_TRY $2 -c -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+printf "yes\n"
+eval "$1=\"\${$1} \$2\""
+eval "$1=\${$1# }"
+return 0
+else
+printf "no\n"
+return 1
+fi
+}
+
+tryldflag () {
+printf "checking whether linker accepts %s... " "$2"
+echo "typedef int x;" > "$tmpc"
+if $CC $LDFLAGS_TRY -nostdlib -shared "$2" -o "$tmpo" "$tmpc" >/dev/null 2>&1 ; then
+printf "yes\n"
+eval "$1=\"\${$1} \$2\""
+eval "$1=\${$1# }"
+return 0
+else
+printf "no\n"
+return 1
+fi
+}
+
+# Beginning of actual script
+
+CFLAGS_AUTO=
+CFLAGS_TRY=
+LDFLAGS_AUTO=
+LDFLAGS_TRY=
+SRCDIR=
+PREFIX=/usr/local
+EXEC_PREFIX='$(PREFIX)'
+BINDIR='$(EXEC_PREFIX)/bin'
+MANDIR='$(PREFIX)/share/man'
+
+for arg ; do
+case "$arg" in
+--help|-h) usage ;;
+--srcdir=*) SRCDIR=${arg#*=} ;;
+--prefix=*) PREFIX=${arg#*=} ;;
+--exec-prefix=*) EXEC_PREFIX=${arg#*=} ;;
+--bindir=*) BINDIR=${arg#*=} ;;
+--sharedir=*) SHAREDIR=${arg#*=} ;;
+--docdir=*) DOCDIR=${arg#*=} ;;
+--mandir=*) MANDIR=${arg#*=} ;;
+--enable-*|--disable-*|--with-*|--without-*|--*dir=*|--build=*) ;;
+-* ) echo "$0: unknown option $arg" ;;
+CC=*) CC=${arg#*=} ;;
+CFLAGS=*) CFLAGS=${arg#*=} ;;
+CPPFLAGS=*) CPPFLAGS=${arg#*=} ;;
+LDFLAGS=*) LDFLAGS=${arg#*=} ;;
+*=*) ;;
+*) ;;
+esac
+done
+
+for i in SRCDIR PREFIX EXEC_PREFIX BINDIR MANDIR ; do
+stripdir $i
+done
+
+#
+# Get the source dir for out-of-tree builds
+#
+if test -z "$SRCDIR" ; then
+SRCDIR="${0%/configure}"
+stripdir SRCDIR
+fi
+abs_builddir="$(pwd)" || fail "$0: cannot determine working directory"
+abs_srcdir="$(cd $SRCDIR && pwd)" || fail "$0: invalid source directory $SRCDIR"
+test "$abs_srcdir" = "$abs_builddir" && SRCDIR=.
+test "$SRCDIR" != "." -a -f Makefile -a ! -h Makefile && fail "$0: Makefile already exists in the working directory"
+
+#
+# Get a temp filename we can use
+#
+i=0
+set -C
+while : ; do i=$(($i+1))
+tmpc="./conf$$-$PPID-$i.c"
+tmpo="./conf$$-$PPID-$i.o"
+2>|/dev/null > "$tmpc" && break
+test "$i" -gt 50 && fail "$0: cannot create temporary file $tmpc"
+done
+set +C
+trap 'rm -f "$tmpc" "$tmpo"' EXIT INT QUIT TERM HUP
+
+#
+# Find a C compiler to use
+#
+printf "checking for C compiler... "
+trycc cc
+trycc gcc
+trycc clang
+printf "%s\n" "$CC"
+test -n "$CC" || { echo "$0: cannot find a C compiler" ; exit 1 ; }
+
+printf "checking whether C compiler works... "
+echo "typedef int x;" > "$tmpc"
+if output=$($CC $CPPFLAGS $CFLAGS -c -o "$tmpo" "$tmpc" 2>&1) ; then
+printf "yes\n"
+else
+printf "no; compiler output follows:\n%s\n" "$output"
+exit 1
+fi
+
+#
+# Figure out options to force errors on unknown flags.
+#
+tryflag   CFLAGS_TRY  -Werror=unknown-warning-option
+tryflag   CFLAGS_TRY  -Werror=unused-command-line-argument
+tryldflag LDFLAGS_TRY -Werror=unknown-warning-option
+tryldflag LDFLAGS_TRY -Werror=unused-command-line-argument
+
+CFLAGS_STD="-std=c99 -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700 -DNDEBUG -D_FORTIFY_SOURCE=2"
+LDFLAGS_STD="-lc -lutil"
+
+OS=$(uname)
+
+case "$OS" in
+FreeBSD) CFLAGS_STD="$CFLAGS_STD -D_BSD_SOURCE -D__BSD_VISIBLE=1" ;;
+*BSD)    CFLAGS_STD="$CFLAGS_STD -D_BSD_SOURCE" ;;
+Darwin)  CFLAGS_STD="$CFLAGS_STD -D_DARWIN_C_SOURCE" ;;
+AIX)     CFLAGS_STD="$CFLAGS_STD -D_ALL_SOURCE" ;;
+esac
+
+tryflag CFLAGS -pipe
+
+# Try flags to optimize binary size
+tryflag CFLAGS -Os
+tryflag CFLAGS -ffunction-sections
+tryflag CFLAGS -fdata-sections
+tryldflag LDFLAGS_AUTO -Wl,--gc-sections
+
+# Try hardening flags
+tryflag CFLAGS -fPIE
+tryflag CFLAGS_AUTO -fstack-protector-all
+tryldflag LDFLAGS -Wl,-z,now
+tryldflag LDFLAGS -Wl,-z,relro
+tryldflag LDFLAGS_AUTO -pie
+
+printf "creating config.mk... "
+
+cmdline=$(quote "$0")
+for i ; do cmdline="$cmdline $(quote "$i")" ; done
+
+exec 3>&1 1>config.mk
+
+cat << EOF
+# This version of config.mk was generated by:
+# $cmdline
+# Any changes made here will be lost if configure is re-run
+SRCDIR = $SRCDIR
+PREFIX = $PREFIX
+EXEC_PREFIX = $EXEC_PREFIX
+BINDIR = $BINDIR
+MANPREFIX = $MANDIR
+CC = $CC
+CFLAGS = $CFLAGS
+LDFLAGS = $LDFLAGS
+CFLAGS_STD = $CFLAGS_STD
+LDFLAGS_STD = $LDFLAGS_STD
+CFLAGS_AUTO = $CFLAGS_AUTO
+LDFLAGS_AUTO = $LDFLAGS_AUTO
+CFLAGS_DEBUG = -U_FORTIFY_SOURCE -UNDEBUG -O0 -g -ggdb -Wall -Wextra -pedantic -Wno-unused-parameter -Wno-sign-compare
+EOF
+exec 1>&3 3>&-
+
+printf "done\n"
+
+test "$SRCDIR" = "." || ln -sf $SRCDIR/Makefile .