From 79f1af7f972386e3c9da60acd14a5764efeec058 Mon Sep 17 00:00:00 2001
From: Guilherme Janczak <guilherme.janczak@yandex.com>
Date: Mon, 23 May 2022 19:40:34 +0000
Subject: [PATCH] port to OpenBSD and Alpine Linux

To do that, I switched to libbsd-overlay, added feature testing to only
depend on libbsd if strlcpy() is not in the libc, added a trick for
automatically getting the include/lib paths for packages without adding
them by hand, and added a dependency on argp-standalone on systems that
don't have glibc's argp API.
---
 configure.ac            | 50 ++++++++++++++++++++---------------------
 src/cvecheck_common.h   |  5 ++---
 src/output/stringscmd.h |  3 +--
 3 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/configure.ac b/configure.ac
index 2539aa8..8b8fadd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -4,24 +4,6 @@ AM_INIT_AUTOMAKE([subdir-objects foreign])
 AC_CONFIG_SRCDIR([config.h.in])
 AC_CONFIG_HEADERS([config.h])
 
-AC_MSG_CHECKING([Determining host operating system])
-OSNAME=`uname -s`
-AC_MSG_RESULT($OSNAME)
-case "$OSNAME" in
-  FreeBSD*)
-    # Include the packages - needed for argp_standalone
-    export CPPFLAGS="$CPPFLAGS -I/usr/local/include"
-    export LDFLAGS="$LDFLAGS -L /usr/local/lib"
-    AC_MSG_RESULT([FreeBSD: adding /usr/local])
-    ;;
-  NetBSD*)
-    # Include the packages - needed for argp
-    export CPPFLAGS="$CPPFLAGS -I/usr/pkg/include"
-    export LDFLAGS="$LDFLAGS -L /usr/pkg/lib"
-    AC_MSG_RESULT([NetBSD: adding /usr/pkg])
-    ;;
-esac
-
 # Checks for programs.
 AC_PROG_CC
 AC_GNU_SOURCE
@@ -30,21 +12,39 @@ AC_GNU_SOURCE
 AC_CHECK_HEADERS([stdlib.h],,[AC_MSG_ERROR([stdlib.h header missing])])
 AC_CHECK_HEADERS([string.h],,[AC_MSG_ERROR([string.h header missing])])
 AC_CHECK_HEADERS([unistd.h],,[AC_MSG_ERROR([unistd.h header missing])])
-AC_CHECK_HEADERS([argp.h],,[AC_MSG_ERROR([argp.h header missing (part of GNU coreutils)])])
-AC_CHECK_HEADERS([string.h],,[AC_MSG_ERROR([string.h header missing])])
 
 # Checks for library functions.
-AC_CHECK_FUNCS([gethostname memset regcomp strchr strrchr strstr strlcpy],,
-  [PKG_CHECK_MODULES([BSD], [libbsd])])
+AC_CHECK_FUNCS([gethostname memset regcomp strchr strrchr strstr])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_SIZE_T
 
+# Checks for dependencies.
 AC_MSG_WARN([Please make sure pkg-config is installed and autoreconf run])
-PKG_CHECK_MODULES([BSD], [libbsd])
+
+# libbsd is obligatory on systems where strlcpy is not in libc.
+# https://man.openbsd.org/strlcpy.3
+# https://libbsd.freedesktop.org/wiki/
+AC_CHECK_FUNC([strlcpy],, [LIBBSD_NEEDED=yes])
+AS_IF([test "x$LIBBSD_NEEDED" = "xyes"], [
+  PKG_CHECK_MODULES([LIBBSD], [libbsd-overlay])
+])
+
 PKG_CHECK_MODULES([CONFIG], [libconfig >= 1.3])
-CFLAGS="$CFLAGS $CONFIG_CFLAGS"
-LIBS="$LIBS $CONFIG_LIBS $BSD_LIBS"
+
+# The BSD systems don't have packages in the default include/library
+# paths. Let our pkg-config dependencies add those paths for us BEFORE we look
+# for argp.
+CFLAGS="$CFLAGS $CONFIG_CFLAGS $LIBBSD_CFLAGS"
+LIBS="$LIBS $CONFIG_LIBS $LIBBSD_LIBS"
+
+# argp-standalone is obligatory on systems where argp is not in libc.
+# https://www.gnu.org/software/libc/manual/html_node/Argp.html
+# https://github.com/argp-standalone/argp-standalone
+AC_SEARCH_LIBS([argp_parse], [argp],,
+  [AC_MSG_ERROR([argp-standalone dependency missing])]
+)
+
 ## --with configs
 # mysql
 AC_ARG_ENABLE(mysql, [  --enable-mysql	Enable MySQL support])
diff --git a/src/cvecheck_common.h b/src/cvecheck_common.h
index 7627c94..1e40723 100644
--- a/src/cvecheck_common.h
+++ b/src/cvecheck_common.h
@@ -1,7 +1,6 @@
 #include <stdio.h>
 #include <libconfig.h>
 #include <string.h>
-#include <bsd/string.h>
 
 #ifdef _USE_SQLITE3
 #include <sqlite3.h>
@@ -15,7 +14,7 @@
  * Copyright 2010-2020 Sven Vermeulen.
  * Subject to the GNU Public License, version 3.
  */
- 
+
 #ifndef _CVETYPES
 #define _CVETYPES
 
@@ -23,7 +22,7 @@
 #define LARGEFIELDSIZE 512
 #define FILENAMESIZE 256
 #define BUFFERSIZE 256
-#define CVELINESIZE 24 
+#define CVELINESIZE 24
 #define CPELINESIZE (7 + FIELDSIZE*11 + 5)
 #define VERSIONLINESIZE (FILENAMESIZE*2 + 5 + CPELINESIZE)
 // Normally, around 1800 ought to be enough (largest SELECT statement with assumption of largest values)
diff --git a/src/output/stringscmd.h b/src/output/stringscmd.h
index f8cba2d..6f70208 100644
--- a/src/output/stringscmd.h
+++ b/src/output/stringscmd.h
@@ -1,7 +1,6 @@
 #include <regex.h>
 #include <stdio.h>
 #include <string.h>
-#include <bsd/string.h>
 #include "../cvecheck_common.h"
 #include "../swstring.h"
 
@@ -11,4 +10,4 @@
  */
 
 // strings_extract_version - Method for extracting the version from the file using the strings command
-int strings_extract_version(struct workstate * ws, regex_t * preg, regmatch_t * pmatch, struct cpe_data * cpe); 
+int strings_extract_version(struct workstate * ws, regex_t * preg, regmatch_t * pmatch, struct cpe_data * cpe);