libxbps: implement xbps_file_exec() with posix_spawn().

3RDPARTY

@@ -13,8 +13,6 @@ internal use in the code:
 
 - mkpath from NetBSD's mkdir(1): lib/external/mkpath.c
 
-- fexec from NetBSD's pkg_install: lib/external/fexec.c
-
 - libfetch-2.31 from NetBSD: lib/fetch
 
 - portableproplib-0.4.1 (lib/portableproplib) from

COPYING

@@ -140,7 +140,7 @@ This product uses some code with the following license
  */
 
 This product uses some code with the following license
-(lib/humanize_number.c, lib/fexec.c):
+(lib/humanize_number.c):
 
 /*
  * Copyright (c) 2003 The NetBSD Foundation, Inc.

NEWS

@@ -1,5 +1,8 @@
 xbps-0.16 (???):
 
+ * libxbps: implemented xbps_file_exec thru posix_spawn. That means
+   posix_spawn() is now required in xbps.
+
  * libxbps: renamed xbps_repository_pool_xxx to xbps_rpool_xxx
    (API/ABI incompat changes).
 

configure

@@ -305,6 +305,28 @@ if [ -n "$BUILD_PIE" ]; then
 	fi
 fi
 
+#
+# Check for posix_spawn (required).
+#
+func=posix_spawn
+printf "Checking for $func() ... "
+cat <<EOF > _$func.c
+#include <stdio.h>
+#include <spawn.h>
+int main(void) {
+	posix_spawn(NULL, NULL, NULL, NULL, NULL, NULL);
+	return 0;
+}
+EOF
+if $XCC _${func}.c -o _${func} 2>/dev/null; then
+	rm -f _$func.c _$func
+	echo "yes."
+else
+	echo "not found! $func is required by xbps, exiting..."
+	rm -f _$func.c _$func
+	exit 1
+fi
+
 #
 # Check for vasprintf().
 #

include/xbps_api.h

@@ -56,7 +56,7 @@
  */
 #define XBPS_PKGINDEX_VERSION	"1.4"
 
-#define XBPS_API_VERSION	"20120530-2"
+#define XBPS_API_VERSION	"20120530-3"
 #define XBPS_VERSION		"0.16"
 
 /**

include/xbps_api_impl.h

@@ -165,11 +165,9 @@ char HIDDEN *xbps_get_remote_repo_string(const char *);
 
 /**
  * @private
- * From lib/fexec.c
+ * From lib/file_exec.c
  */
 int HIDDEN xbps_file_exec(const char *, ...);
-int HIDDEN xbps_file_exec_skipempty(const char *, ...);
-int HIDDEN xbps_file_chdir_exec(const char *, const char *, ...);
 
 /**
  * @private

lib/Makefile

@@ -37,7 +37,7 @@ LIBFETCH_OBJS =
 endif
 
 # External code used by libxbps
-EXTOBJS = external/dewey.o external/fexec.o external/humanize_number.o
+EXTOBJS = external/dewey.o external/humanize_number.o
 EXTOBJS += external/match.o external/mkpath.o
 
 # libxbps
@@ -46,7 +46,7 @@ OBJS += package_remove.o package_remove_obsoletes.o package_state.o
 OBJS += package_unpack.o package_requiredby.o package_register.o
 OBJS += transaction_commit.o transaction_package_replace.o
 OBJS += transaction_dictionary.o transaction_sortdeps.o transaction_ops.o
-OBJS += download.o initend.o pkgdb.o
+OBJS += download.o initend.o pkgdb.o file_exec.o
 OBJS += plist.o plist_archive_entry.o plist_find.o plist_match.o
 OBJS += plist_remove.o plist_fetch.o util.o util_hash.o 
 OBJS += repository_finddeps.o cb_util.o

lib/external/fexec.c

@@ -1,173 +0,0 @@
-/*-
- * Copyright (c) 2003 The NetBSD Foundation, Inc.
- * All rights reserved.
- *
- * This code is derived from software contributed to The NetBSD Foundation
- * by Matthias Scheler.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
- * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
- * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <errno.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include "xbps_api_impl.h"
-
-static int
-pfcexec(const char *path, const char *file, const char **argv)
-{
-	pid_t			child;
-	int			status;
-	bool			do_chroot = false;
-
-	child = vfork();
-	switch (child) {
-	case 0:
-		if (getuid() == 0 && access("./bin/sh", X_OK) == 0)
-			do_chroot = true;
-
-		/*
-		 * If uid==0 and /bin/sh exists, we can change root directory,
-		 * fork and execute the command. Otherwise just change current
-		 * directory and fork/execute.
-		 */
-		if (path && do_chroot) {
-			if (chroot(path) == -1)
-				_exit(127);
-			if (chdir("/") == -1)
-				_exit(127);
-		} else if (path && !do_chroot) {
-			if (chdir(path) == -1)
-				_exit(127);
-		} else if (path == NULL && do_chroot) {
-			if (chroot(".") == -1) {
-				if (errno != EPERM)
-					_exit(127);
-				if (chdir(".") == -1)
-					_exit(127);
-			} else {
-				if (chdir("/") == -1)
-					_exit(127);
-			}
-		}
-
-		(void)execv(file, __UNCONST(argv));
-		_exit(127);
-		/* NOTREACHED */
-	case -1:
-		return -1;
-	}
-
-	while (waitpid(child, &status, 0) < 0) {
-		if (errno != EINTR)
-			return -1;
-	}
-
-	if (!WIFEXITED(status))
-		return -1;
-
-	return WEXITSTATUS(status);
-}
-
-static int
-vfcexec(const char *path, int skipempty, const char *arg, va_list ap)
-{
-	const char **argv;
-	size_t argv_size, argc;
-	int retval;
-
-	argv_size = 16;
-	if ((argv = malloc(argv_size * sizeof(*argv))) == NULL) {
-		errno = ENOMEM;
-		return -1;
-	}
-
-	argv[0] = arg;
-	argc = 1;
-
-	do {
-		if (argc == argv_size) {
-			argv_size *= 2;
-			argv = realloc(argv, argv_size * sizeof(*argv));
-			if (argv == NULL) {
-				errno = ENOMEM;
-				return -1;
-			}
-		}
-
-		arg = va_arg(ap, const char *);
-		if (skipempty && arg && strlen(arg) == 0)
-		    continue;
-
-		argv[argc++] = arg;
-
-	} while (arg != NULL);
-
-	retval = pfcexec(path, argv[0], argv);
-	free(argv);
-
-	return retval;
-}
-
-int HIDDEN
-xbps_file_exec(const char *arg, ...)
-{
-	va_list	ap;
-	int	result;
-
-	va_start(ap, arg);
-	result = vfcexec(NULL, 0, arg, ap);
-	va_end(ap);
-
-	return result;
-}
-
-int HIDDEN
-xbps_file_exec_skipempty(const char *arg, ...)
-{
-	va_list	ap;
-	int	result;
-
-	va_start(ap, arg);
-	result = vfcexec(NULL, 1, arg, ap);
-	va_end(ap);
-
-	return result;
-}
-
-int HIDDEN
-xbps_file_chdir_exec(const char *path, const char *arg, ...)
-{
-	va_list	ap;
-	int	result;
-
-	va_start(ap, arg);
-	result = vfcexec(path, 0, arg, ap);
-	va_end(ap);
-
-	return result;
-}

lib/file_exec.c

@@ -0,0 +1,108 @@
+/*-
+ * Copyright (c) 2012 Juan Romero Pardines.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <spawn.h>
+
+#include "xbps_api_impl.h"
+
+static int
+pfcexec(const char *file, const char **argv)
+{
+	pid_t			child;
+	int			status, rv;
+
+	if (((getuid() == 0) && (access("bin/sh", X_OK) == 0))) {
+		if ((chroot(".") != 0) && (chdir("/") != 0))
+			return errno;
+	}
+	if ((rv = posix_spawn(&child, file, NULL, NULL,
+			      (char ** const)__UNCONST(argv),
+			      NULL)) == 0) {
+		while (waitpid(child, &status, 0) < 0) {
+			if (errno != EINTR)
+				return errno;
+		}
+		if (!WIFEXITED(status))
+			return errno;
+
+		return WEXITSTATUS(status);
+	}
+	return rv;
+}
+
+static int
+vfcexec(const char *arg, va_list ap)
+{
+	const char **argv;
+	size_t argv_size, argc;
+	int retval;
+
+	argv_size = 16;
+	if ((argv = malloc(argv_size * sizeof(*argv))) == NULL) {
+		errno = ENOMEM;
+		return -1;
+	}
+	argv[0] = arg;
+	argc = 1;
+
+	do {
+		if (argc == argv_size) {
+			argv_size *= 2;
+			argv = realloc(argv, argv_size * sizeof(*argv));
+			if (argv == NULL) {
+				errno = ENOMEM;
+				return -1;
+			}
+		}
+		arg = va_arg(ap, const char *);
+		argv[argc++] = arg;
+
+	} while (arg != NULL);
+
+	retval = pfcexec(argv[0], argv);
+	free(argv);
+
+	return retval;
+}
+
+int HIDDEN
+xbps_file_exec(const char *arg, ...)
+{
+	va_list	ap;
+	int	result;
+
+	va_start(ap, arg);
+	result = vfcexec(arg, ap);
+	va_end(ap);
+
+	return result;
+}