add long options step1

add the long options to lxc-execute as an exemple
of usage of the new functions added in src/lxc/arguments.*

Signed-off-by: Michel Normand <normand@fr.ibm.com>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>

src/lxc/Makefile.am

@@ -19,6 +19,7 @@ pkginclude_HEADERS = \
 
 
 liblxc_la_SOURCES = \
+	arguments.c arguments.h \
 	create.c \
 	destroy.c \
 	start.c \

src/lxc/arguments.c

@@ -0,0 +1,203 @@
+/*
+ * lxc: linux Container library
+ *
+ * (C) Copyright IBM Corp. 2007, 2008
+ *
+ * Authors:
+ * Daniel Lezcano <dlezcano at fr.ibm.com>
+ * Michel Normand <normand at fr.ibm.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <string.h>
+#include <ctype.h>		/* for isprint() */
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "arguments.h"
+
+/*---------------------------------------------------------------------------*/
+static int build_shortopts(const struct option *a_options,
+			   char *a_shortopts, size_t a_size)
+{
+	const struct option *opt;
+	int i = 0;
+
+	if (!a_options || !a_shortopts || !a_size)
+		return -1;
+
+	for (opt = a_options; opt->name; opt++) {
+
+		if (!isascii(opt->val))
+			continue;
+
+		if (i < a_size)
+			a_shortopts[i++] = opt->val;
+		else
+			goto is2big;
+
+		if (opt->has_arg == no_argument)
+			continue;
+
+		if (i < a_size)
+			a_shortopts[i++] = ':';
+		else
+			goto is2big;
+
+		if (opt->has_arg == required_argument)
+			continue;
+
+		if (i < a_size)
+			a_shortopts[i++] = ':';
+		else
+			goto is2big;
+	}
+
+	if (i < a_size)
+		a_shortopts[i] = '\0';
+	else
+		goto is2big;
+
+	return 0;
+
+      is2big:
+	errno = E2BIG;
+	return -1;
+}
+
+/*---------------------------------------------------------------------------*/
+static void print_usage(const struct option longopts[],
+			const struct lxc_arguments *a_args)
+
+{
+	int i;
+	const struct option *opt;
+
+	fprintf(stderr, "Usage: %s ", a_args->progname);
+
+	for (opt = longopts, i = 1; opt->name; opt++, i++) {
+		int j;
+		char *uppername = strdup(opt->name);
+
+		for (j = 0; uppername[j]; j++)
+			uppername[j] = toupper(uppername[j]);
+
+		fprintf(stderr, "[");
+
+		if (isprint(opt->val))
+			fprintf(stderr, "-%c|", opt->val);
+
+		fprintf(stderr, "--%s", opt->name);
+
+		if (opt->has_arg == required_argument)
+			fprintf(stderr, "=%s", uppername);
+
+		if (opt->has_arg == optional_argument)
+			fprintf(stderr, "[=%s]", uppername);
+
+		fprintf(stderr, "] ");
+
+		if (!(i % 4))
+			fprintf(stderr, "\n\t");
+
+		free(uppername);
+	}
+
+	fprintf(stderr, "\n");
+	exit(0);
+}
+
+static void print_help(const struct lxc_arguments *args, int code)
+{
+	fprintf(stderr, "\
+Usage: %s %s\
+\n\
+Common options :\n\
+  -o, --logfile=FILE               Output log to FILE instead of stderr\n\
+  -l, --logpriority=LEVEL          Set log priority to LEVEL\n\
+  -q, --quiet                      Don't produce any output\n\
+  -?, --help                       Give this help list\n\
+      --usage                      Give a short usage message\n\
+\n\
+Mandatory or optional arguments to long options are also mandatory or optional\n\
+for any corresponding short options.\n\
+\n\
+See the %s man page for further information.\n\n",
+	args->progname, args->help, args->progname);
+
+	exit(code);
+}
+
+extern int lxc_arguments_parse(struct lxc_arguments *args,
+			       int argc, char * const argv[])
+{
+	char shortopts[256];
+	int  ret = 0;
+
+	ret = build_shortopts(args->options, shortopts, sizeof(shortopts));
+	if (ret < 0) {
+		lxc_error(args, "build_shortopts() failed : %s",
+			  strerror(errno));
+		return ret;
+	}
+
+	while (1)  {
+		int c, index = 0;
+
+		c = getopt_long(argc, argv, shortopts, args->options, &index);
+		if (c == -1)
+			break;
+		switch (c) {
+		case 'n': 	args->name = optarg; break;
+		case 'o':	args->log_file = optarg; break;
+		case 'l':	args->log_priority = optarg; break;
+		case 'q':	args->quiet = 1; break;
+		case OPT_USAGE: print_usage(args->options, args);
+		case '?':	print_help(args, 1);
+		case 'h': 	print_help(args, 0);
+		default:
+			if (args->parser) {
+				ret = args->parser(args, c, optarg);
+				if (ret)
+					goto error;
+			}
+		}
+	}
+
+	/*
+	 * Reclaim the remaining command arguments
+	 */
+	args->argv = &argv[optind];
+	args->argc = argc - optind;
+
+	/* Check the command options */
+
+	if (!args->name) {
+		lxc_error(args, "missing container name, use --name option");
+		return -1;
+	}
+
+	if (args->checker)
+		ret = args->checker(args);
+error:
+	if (ret)
+		lxc_error(args, "could not parse command line");
+	return ret;
+}

src/lxc/arguments.h

@@ -0,0 +1,71 @@
+/*
+ * lxc: linux Container library
+ *
+ * (C) Copyright IBM Corp. 2007, 2008
+ *
+ * Authors:
+ * Daniel Lezcano <dlezcano at fr.ibm.com>
+ * Michel Normand <normand at fr.ibm.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#ifndef __arguments_h
+#define __arguments_h
+
+#include <getopt.h>
+
+struct lxc_arguments;
+
+typedef int (*lxc_arguments_parser_t) (struct lxc_arguments *, int, char*);
+typedef int (*lxc_arguments_checker_t) (const struct lxc_arguments *);
+
+struct lxc_arguments {
+	const char *help;
+	const char *progname;
+	const struct option* options;
+	lxc_arguments_parser_t parser;
+	lxc_arguments_checker_t checker;
+
+	const char *name;
+	char *log_file;
+	char *log_priority;
+	int quiet;
+	const char *rcfile;
+
+	/* remaining arguments */
+	char *const *argv;
+	int argc;
+};
+
+#define LXC_COMMON_OPTIONS \
+	{"name", required_argument, 0, 'n'}, \
+	{"help", no_argument, 0, 'h'}, \
+	{"usage", no_argument,	0, OPT_USAGE}, \
+	{"quiet", no_argument,	0, 'q'}, \
+	{"logfile", required_argument, 0, 'o'}, \
+	{"logpriority", required_argument, 0, 'l'}, \
+	{0, 0, 0, 0}
+
+/* option keys for long only options */
+#define	OPT_USAGE 0x1000
+
+extern int lxc_arguments_parse(struct lxc_arguments *a_args,
+			       int argc, char *const argv[]);
+extern const char *lxc_strerror(int errnum);
+
+#define lxc_error(arg, fmt, args...) if (!(arg)->quiet)			\
+	fprintf(stderr, "%s: " fmt "\n", (arg)->progname,  ## args)
+
+#endif

src/lxc/lxc_execute.c

@@ -32,72 +32,74 @@
 
 #include <lxc/lxc.h>
 #include "confile.h"
+#include "arguments.h"
 
 lxc_log_define(lxc_execute, lxc);
 
-void usage(char *cmd)
+static int my_checker(const struct lxc_arguments* args)
 {
-	fprintf(stderr, "%s <command>\n", basename(cmd));
+	if (!args->argc) {
-	fprintf(stderr, "\t -n <name>      : name of the container\n");
+		lxc_error(args, "missing command to execute !");
-	fprintf(stderr, "\t [-f <confile>] : path of the configuration file\n");
+		return -1;
-	fprintf(stderr, "\t[-o <logfile>]    : path of the log file\n");
+	}
-	fprintf(stderr, "\t[-l <logpriority>]: log level priority\n");
+	return 0;
-	fprintf(stderr, "\t[-q ]             : be quiet\n");
-	_exit(1);
 }
 
+static int my_parser(struct lxc_arguments* args, int c, char* arg)
+{
+	switch (c) {
+	case 'f': args->rcfile = arg; break;
+	}
+	return 0;
+}
+
+static const struct option my_longopts[] = {
+	{"rcfile", required_argument, 0, 'f'},
+	LXC_COMMON_OPTIONS
+};
+
+static struct lxc_arguments my_args = {
+	.progname = "lxc-execute",
+	.help     = "\
+--name=NAME -- COMMAND\n\
+\n\
+lxc-execute creates a container with the identifier NAME\n\
+and execs COMMAND into this container.\n\
+\n\
+Options :\n\
+  -n, --name=NAME   NAME for name of the container\n\
+  -f, --rcfile=FILE Load configuration file FILE\n",
+	.options  = my_longopts,
+	.parser   = my_parser,
+	.checker  = my_checker,
+};
+
 int main(int argc, char *argv[])
 {
-	const char *name = NULL, *file = NULL;
-	const char *log_file = NULL, *log_priority = NULL;
 	static char **args;
 	char path[MAXPATHLEN];
 	int opt;
 	int nbargs = 0;
 	int autodestroy = 0;
 	int ret = 1;
-	int quiet = 0;
 	struct lxc_conf lxc_conf;
 
-	while ((opt = getopt(argc, argv, "f:n:o:l:q")) != -1) {
+	if (lxc_arguments_parse(&my_args, argc, argv))
-		switch (opt) {
+		goto out;
-		case 'n':
-			name = optarg;
-			break;
-		case 'f':
-			file = optarg;
-			break;
-		case 'o':
-			log_file = optarg;
-			break;
-		case 'l':
-			log_priority = optarg;
-			break;
-		case 'q':
-			quiet = 1;
-			break;
-		}
 
-		nbargs++;
+	if (lxc_log_init(my_args.log_file, my_args.log_priority,
-	}
+			 my_args.progname, my_args.quiet))
-
-	if (!name || !argv[optind] || !strlen(argv[optind]))
-		usage(argv[0]);
-
-	argc -= nbargs;
-	
-	if (lxc_log_init(log_file, log_priority, basename(argv[0]), quiet))
 		goto out;
 
 	if (lxc_conf_init(&lxc_conf))
 		goto out;
 
-	if (file && lxc_config_read(file, &lxc_conf))
+	if (my_args.rcfile && lxc_config_read(my_args.rcfile, &lxc_conf))
 		goto out;
 
-	snprintf(path, MAXPATHLEN, LXCPATH "/%s", name);
+	snprintf(path, MAXPATHLEN, LXCPATH "/%s", my_args.name);
 	if (access(path, R_OK)) {
-		if (lxc_create(name, &lxc_conf))
+		if (lxc_create(my_args.name, &lxc_conf))
 			goto out;
 		autodestroy = 1;
 	}
@@ -105,7 +107,7 @@ int main(int argc, char *argv[])
 	/* lxc-init --mount-procfs -- .... */
 	args = malloc((argc + 3)*sizeof(*args));
 	if (!args) {
-		ERROR("failed to allocate memory for '%s'", name);
+		ERROR("failed to allocate memory for '%s'", my_args.name);
 		goto out;
 	}
 
@@ -114,20 +116,20 @@ int main(int argc, char *argv[])
 	args[nbargs++] = "--mount-procfs";
 	args[nbargs++] = "--";
 
-	for (opt = 0; opt < argc; opt++)
+	for (opt = 0; opt < my_args.argc; opt++)
-		args[nbargs++] = argv[optind++];
+		args[nbargs++] = my_args.argv[opt];
 
-	ret = lxc_start(name, args);
+	ret = lxc_start(my_args.name, args);
 	if (ret) {
-		ERROR("failed to start '%s'", name);
+		ERROR("failed to start '%s'", my_args.name);
 		goto out;
 	}
 
 	ret = 0;
 out:
 	if (autodestroy) {
-		if (lxc_destroy(name)) {
+		if (lxc_destroy(my_args.name)) {
-			ERROR("failed to destroy '%s'", name);
+			ERROR("failed to destroy '%s'", my_args.name);
 			ret = 1;
 		}
 	}