X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=ustctl%2Fcli.c;fp=ustctl%2Fcli.c;h=0ca9db5c632e7877c1ef80ec87dedf7071c46f70;hb=0c89df6cb75f1d967003137e7fc334af1128a42f;hp=0000000000000000000000000000000000000000;hpb=91594b712729c0d855efeab849c2093706336941;p=ust.git

diff --git a/ustctl/cli.c b/ustctl/cli.c
new file mode 100644
index 0000000..0ca9db5
--- /dev/null
+++ b/ustctl/cli.c
@@ -0,0 +1,207 @@
+/* Copyright (C) 2011  Ericsson AB, Nils Carlson <nils.carlson@ericsson.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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "cli.h"
+
+/* This dummy command is needed to create the sections in cli.o before
+ *  other .o files have these sections, usefull for development.
+ */
+static int _dummy(int argc, char *argv[]) {
+	return 0;
+}
+
+/* Define a dummy cmd to guarantee existence of the builtin variables */
+struct cli_cmd __cli_cmds __dummy_cli_cmd[] = {
+	{
+		.name = "_dummy",
+		.description = NULL,
+		.help_text = NULL,
+		.function = _dummy,
+		.desired_args = 0,
+		.desired_args_op = 0,
+	},
+};
+
+extern struct cli_cmd __start___cli_cmds[] __attribute__((visibility("hidden")));
+extern struct cli_cmd __stop___cli_cmds[] __attribute__((visibility("hidden")));
+
+static struct cli_cmd **cli_cmd_list;
+static int cli_cmd_list_size;
+
+static char *process_name;
+
+static int compute_cli_cmds_size(void)
+{
+	long cli_cmds_start, cli_cmds_end;
+
+	cli_cmds_start = (long)__start___cli_cmds;
+	cli_cmds_end = (long)__stop___cli_cmds;
+
+	return (cli_cmds_end - cli_cmds_start) / sizeof(struct cli_cmd);
+}
+
+static void __attribute__((constructor)) generate_cli_cmd_list(int argc, char *argv[])
+{
+	struct cli_cmd *cli_cmd;
+	int section_size, i;
+
+	process_name = basename(argv[0]);
+
+	section_size = compute_cli_cmds_size();
+
+	cli_cmd_list = malloc(section_size * sizeof(void *));
+	if (!cli_cmd_list) {
+		fprintf(stderr, "Failed to allocate command list!");
+		exit(EXIT_FAILURE);
+	}
+
+	cli_cmd_list_size = 0;
+
+	cli_cmd = __start___cli_cmds;
+	for (i = 0; i < section_size; i++) {
+		if (&cli_cmd[i] == &__dummy_cli_cmd[0]) {
+			continue;
+		}
+
+		if (cli_cmd[i].name) {
+			cli_cmd_list[cli_cmd_list_size++] = &cli_cmd[i];
+		}
+	}
+}
+
+struct cli_cmd *find_cli_cmd(const char *command)
+{
+	int i;
+
+	for (i = 0; i < cli_cmd_list_size; i++) {
+		if (!strcmp(cli_cmd_list[i]->name, command)) {
+			return cli_cmd_list[i];
+		}
+	}
+
+	return NULL;
+}
+
+static int cmpcli_cmds(const void *p1, const void *p2)
+{
+	return strcmp(* (char * const *) ((struct cli_cmd *)p1)->name,
+		      * (char * const *) ((struct cli_cmd *)p2)->name);
+}
+
+#define HELP_BUFFER_SIZE 4096
+
+static void print_cmd_help(const char *prefix, const char *infix,
+			   struct cli_cmd *cli_cmd)
+{
+	if (cli_cmd->help_text) {
+		fprintf(stderr, "%s%s%s",
+			prefix,
+			infix,
+			cli_cmd->help_text);
+	} else if (cli_cmd->description) {
+		fprintf(stderr, "%s%s%s\n%s\n",
+			prefix,
+			infix,
+			cli_cmd->name,
+			cli_cmd->description);
+	} else {
+		fprintf(stderr, "No help available for %s\n",
+			cli_cmd->name);
+	}
+}
+
+void list_cli_cmds(int option)
+{
+	int i;
+
+	qsort(cli_cmd_list, cli_cmd_list_size, sizeof(void *), cmpcli_cmds);
+
+	for (i = 0; i < cli_cmd_list_size; i++) {
+		switch (option) {
+		case CLI_SIMPLE_LIST:
+			fprintf(stderr, "%s ", cli_cmd_list[i]->name);
+			break;
+		case CLI_DESCRIPTIVE_LIST:
+			fprintf(stderr, "   %-25s%s\n", cli_cmd_list[i]->name,
+				cli_cmd_list[i]->description);
+			break;
+		case CLI_EXTENDED_LIST:
+			print_cmd_help("", "", cli_cmd_list[i]);
+			fprintf(stderr, "\n");
+			break;
+		}
+	}
+
+	if (option == CLI_SIMPLE_LIST) {
+		fprintf(stderr, "\n");
+	}
+}
+
+int cli_print_help(const char *command)
+{
+	struct cli_cmd *cli_cmd;
+
+	cli_cmd = find_cli_cmd(command);
+	if (!cli_cmd) {
+		return -1;
+	}
+
+	print_cmd_help(process_name, " ", cli_cmd);
+
+	return 0;
+}
+
+static void cli_check_argc(const char *command, int args,
+			   int operator, int desired_args)
+{
+	switch(operator) {
+	case CLI_EQ:
+		if (args != desired_args)
+			goto print_error;
+		break;
+	case CLI_GE:
+		if (args < desired_args)
+			goto print_error;
+		break;
+	}
+
+	return;
+
+print_error:
+	fprintf(stderr, "%s %s requires %s%d argument%s, see usage.\n",
+		process_name, command, operator == CLI_EQ ? "" : "at least ",
+		desired_args, desired_args > 1 ? "s" : "");
+	cli_print_help(command);
+	exit(EXIT_FAILURE);
+}
+
+
+void cli_dispatch_cmd(struct cli_cmd *cmd, int argc, char *argv[])
+{
+	cli_check_argc(cmd->name, argc - 1, cmd->desired_args_op,
+		       cmd->desired_args);
+
+	if (cmd->function(argc, argv)) {
+		exit(EXIT_FAILURE);
+	}
+
+	exit(EXIT_SUCCESS);
+}