[Ocfs2-tools-devel] [PATCH 16/19] Ocfs2-tools: Add main.c to o2info.

[tristan]

Sunil Mushran wrote:
> So the outer shell of main.c should be earlier in the series.
> As you add support for commands, like volinfo, you can add
> the appropriate support here. That makes reviewing easier.

Thank you for pointing this out, I remembered tao has told me such 
things before as well. Sorry for not following the rules.


>
> Tristan Ye wrote:
>> It handles the parsing of options, links the operational
>> tasks to list, then schedules to run task one bye one.
>>
>> To add a new operation task for o2info(such as --volinfo)
>>
>> 1. declare a new extern operation structure.
>> extern struct o2info_operation volinfo_op;
>>
>> 2. add a new option:
>> static struct o2info_option volinfo_option = {
>> .opt_option = {
>> .name = "volinfo",
>> .val = 'V',
>> .has_arg = 0,
>> .flag = NULL,
>> },
>> .opt_help =
>> "-V|--volinfo",
>> .opt_handler = NULL,
>> .opt_op = &volinfo_op,
>> .opt_private = NULL,
>> };
>>
>> 3. Implement the real codes for volinfo_op in operation.c
>>
>> Signed-off-by: Tristan Ye <tristan.ye at oracle.com>
>> ---
>> o2info/main.c | 601 
>> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>> 1 files changed, 601 insertions(+), 0 deletions(-)
>> create mode 100644 o2info/main.c
>>
>> diff --git a/o2info/main.c b/o2info/main.c
>> new file mode 100644
>> index 0000000..174aa75
>> --- /dev/null
>> +++ b/o2info/main.c
>> @@ -0,0 +1,601 @@
>> +/* -*- mode: c; c-basic-offset: 8; -*-
>> + * vim: noexpandtab sw=8 ts=8 sts=0:
>> + *
>> + * main.c
>> + *
>> + * Ocfs2 utility to gather and report fs information
>> + *
>> + * Copyright (C) 2010 Oracle. All rights reserved.
>> + *
>> + * This program is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU General Public
>> + * License version 2 as published by the Free Software Foundation.
>> + *
>> + * This program 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
>> + * General Public License for more details.
>> + */
>> +
>> +#define _XOPEN_SOURCE 600
>> +#define _LARGEFILE64_SOURCE
>> +#define _GNU_SOURCE /* Because libc really doesn't want us using 
>> O_DIRECT? */
>> +
>> +#include <unistd.h>
>> +#include <errno.h>
>> +#include <signal.h>
>> +#include <getopt.h>
>> +#include <assert.h>
>> +
>> +#include "ocfs2/ocfs2.h"
>> +#include "ocfs2-kernel/ocfs2_ioctl.h"
>> +#include "ocfs2-kernel/kernel-list.h"
>> +#include "tools-internal/verbose.h"
>> +
>> +#include "utils.h"
>> +
>> +extern struct o2info_operation volinfo_op;
>> +extern struct o2info_operation fs_features_op;
>> +extern struct o2info_operation usage_op;
>> +extern struct o2info_operation filestat_op;
>> +extern struct o2info_operation freefrag_op;
>> +extern struct o2info_operation freeinode_op;
>> +
>> +static LIST_HEAD(o2info_op_task_list);
>> +static int o2info_op_task_count;
>> +int no_coherency;
>> +
>> +void print_usage(int rc);
>> +static int help_handler(struct o2info_option *opt, char *arg)
>> +{
>> + print_usage(0);
>> + exit(0);
>> +}
>> +
>> +static int version_handler(struct o2info_option *opt, char *arg)
>> +{
>> + tools_version();
>> + exit(0);
>> +}
>> +
>> +static int coherency_handler(struct o2info_option *opt, char *arg)
>> +{
>> + no_coherency = OCFS2_INFO_FL_NON_COHERENT;
>> +
>> + return 0;
>> +}
>> +
>> +static struct o2info_option help_option = {
>> + .opt_option = {
>> + .name = "help",
>> + .val = 'h',
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = NULL,
>> + .opt_handler = help_handler,
>> + .opt_op = NULL,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option version_option = {
>> + .opt_option = {
>> + .name = "version",
>> + .val = 'V',
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = NULL,
>> + .opt_handler = version_handler,
>> + .opt_op = NULL,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option coherency_option = {
>> + .opt_option = {
>> + .name = "no-coherency",
>> + .val = 'F',
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help =
>> + "-F|--no-coherency",
>> + .opt_handler = coherency_handler,
>> + .opt_op = NULL,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option volinfo_option = {
>> + .opt_option = {
>> + .name = "volinfo",
>> + .val = CHAR_MAX,
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = " --volinfo",
>> + .opt_handler = NULL,
>> + .opt_op = &volinfo_op,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option fs_features_option = {
>> + .opt_option = {
>> + .name = "fs-features",
>> + .val = CHAR_MAX,
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = " --fs-features",
>> + .opt_handler = NULL,
>> + .opt_op = &fs_features_op,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option usage_option = {
>> + .opt_option = {
>> + .name = "space-usage",
>> + .val = CHAR_MAX,
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = " --space-usage",
>> + .opt_handler = NULL,
>> + .opt_op = &usage_op,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option filestat_option = {
>> + .opt_option = {
>> + .name = "file-statistics",
>> + .val = CHAR_MAX,
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = " --file-statistics",
>> + .opt_handler = NULL,
>> + .opt_op = &filestat_op,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option freefrag_option = {
>> + .opt_option = {
>> + .name = "freefrag",
>> + .val = CHAR_MAX,
>> + .has_arg = 1,
>> + .flag = NULL,
>> + },
>> + .opt_help = " --freefrag <chunksize in KB>",
>> + .opt_handler = NULL,
>> + .opt_op = &freefrag_op,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option freeinode_option = {
>> + .opt_option = {
>> + .name = "freeinode",
>> + .val = CHAR_MAX,
>> + .has_arg = 0,
>> + .flag = NULL,
>> + },
>> + .opt_help = " --freeinode",
>> + .opt_handler = NULL,
>> + .opt_op = &freeinode_op,
>> + .opt_private = NULL,
>> +};
>> +
>> +static struct o2info_option *options[] = {
>> + &help_option,
>> + &version_option,
>> + &volinfo_option,
>> + &fs_features_option,
>> + &usage_option,
>> + &filestat_option,
>> + &freefrag_option,
>> + &freeinode_option,
>> + &coherency_option,
>> + NULL,
>> +};
>> +
>> +void print_usage(int rc)
>> +{
>> + int i;
>> + enum tools_verbosity_level level = VL_ERR;
>> +
>> + if (!rc)
>> + level = VL_OUT;
>> +
>> + verbosef(level, "Usage: %s [options] <device or file>\n",
>> + tools_progname());
>> + verbosef(level, " %s -h|--help\n", tools_progname());
>> + verbosef(level, " %s -V|--version\n", tools_progname());
>> + verbosef(level, "[options] can be followings:\n");
>> +
>> + for (i = 0; options[i]; i++) {
>> + if (options[i]->opt_help)
>> + verbosef(level, "\t%s\n", options[i]->opt_help);
>> + }
>> +
>> + exit(rc);
>> +}
>> +
>> +static int build_options(char **optstring, struct option **longopts)
>> +{
>> + errcode_t err;
>> + int i, num_opts, rc = 0;
>> + int unprintable_counter;
>> + size_t optstring_len;
>> + char *p, *str = NULL;
>> + struct option *lopts = NULL;
>> + struct o2info_option *opt;
>> +
>> + unprintable_counter = 1; /* Start unique at CHAR_MAX + 1*/
>> + optstring_len = 1; /* For the leading ':' */
>> + for (i = 0; options[i]; i++) {
>> + opt = options[i];
>> +
>> + /*
>> + * Any option with a val of CHAR_MAX wants an unique but
>> + * unreadable ->val. Only readable characters go into
>> + * optstring.
>> + */
>> + if (opt->opt_option.val == CHAR_MAX) {
>> + opt->opt_option.val =
>> + CHAR_MAX + unprintable_counter;
>> + unprintable_counter++;
>> + continue;
>> + }
>> +
>> + /*
>> + * A given option has a single character in optstring.
>> + * If it takes a mandatory argument, has_arg==1 and you add
>> + * a ":" to optstring. If it takes an optional argument,
>> + * has_arg==2 and you add "::" to optstring. Thus,
>> + * 1 + has_arg is the total space needed in opstring.
>> + */
>> + optstring_len += 1 + opt->opt_option.has_arg;
>> + }
>> +
>> + num_opts = i;
>> +
>> + err = ocfs2_malloc0(sizeof(char) * (optstring_len + 1), &str);
>> + if (!err)
>> + err = ocfs2_malloc(sizeof(struct option) * (num_opts + 1),
>> + &lopts);
>> + if (err) {
>> + rc = -ENOMEM;
>> + goto out;
>> + }
>> +
>> + p = str;
>> + *p++ = ':';
>> + for (i = 0; options[i]; i++) {
>> + assert(p < (str + optstring_len + 1));
>> + opt = options[i];
>> +
>> + memcpy(&lopts[i], &opt->opt_option, sizeof(struct option));
>> +
>> + if (opt->opt_option.val >= CHAR_MAX)
>> + continue;
>> +
>> + *p = opt->opt_option.val;
>> + p++;
>> + if (opt->opt_option.has_arg > 0) {
>> + *p = ':';
>> + p++;
>> + }
>> + if (opt->opt_option.has_arg > 1) {
>> + *p = ':';
>> + p++;
>> + }
>> + }
>> +
>> + /*
>> + * Fill last entry of options with zeros.
>> + */
>> + memset(&lopts[i], 0, sizeof(struct option));
>> +
>> +out:
>> + if (!rc) {
>> + *optstring = str;
>> + *longopts = lopts;
>> + } else {
>> + if (str)
>> + free(str);
>> + if (lopts)
>> + free(lopts);
>> + }
>> +
>> + return rc;
>> +}
>> +
>> +static struct o2info_option *find_option_by_val(int val)
>> +{
>> + int i;
>> + struct o2info_option *opt = NULL;
>> +
>> + for (i = 0; options[i]; i++) {
>> + if (options[i]->opt_option.val == val) {
>> + opt = options[i];
>> + break;
>> + }
>> + }
>> +
>> + return opt;
>> +}
>> +
>> +static errcode_t o2info_append_task(struct o2info_operation *o2p)
>> +{
>> + errcode_t err;
>> + struct o2info_op_task *task;
>> +
>> + err = ocfs2_malloc0(sizeof(struct o2info_op_task), &task);
>> + if (!err) {
>> + task->o2p_task = o2p;
>> + list_add_tail(&task->o2p_list, &o2info_op_task_list);
>> + o2info_op_task_count++;
>> + } else
>> + ocfs2_free(&task);
>> +
>> + return err;
>> +}
>> +
>> +static void o2info_free_op_task_list(void)
>> +{
>> + struct o2info_op_task *task;
>> + struct list_head *pos, *next;
>> +
>> + if (list_empty(&o2info_op_task_list))
>> + return;
>> +
>> + list_for_each_safe(pos, next, &o2info_op_task_list) {
>> + task = list_entry(pos, struct o2info_op_task, o2p_list);
>> + list_del(pos);
>> + ocfs2_free(&task);
>> + }
>> +}
>> +
>> +extern int optind, opterr, optopt;
>> +extern char *optarg;
>> +static errcode_t parse_options(int argc, char *argv[], char 
>> **device_or_file)
>> +{
>> + int c, lopt_idx = 0;
>> + errcode_t err;
>> + struct option *long_options = NULL;
>> + char error[PATH_MAX];
>> + char *optstring = NULL;
>> + struct o2info_option *opt;
>> +
>> + err = build_options(&optstring, &long_options);
>> + if (err)
>> + goto out;
>> +
>> + opterr = 0;
>> + error[0] = '\0';
>> + while ((c = getopt_long(argc, argv, optstring,
>> + long_options, &lopt_idx)) != EOF) {
>> + opt = NULL;
>> + switch (c) {
>> + case '?':
>> + if (optopt)
>> + errorf("Invalid option: '-%c'\n", optopt);
>> + else
>> + errorf("Invalid option: '%s'\n",
>> + argv[optind - 1]);
>> + print_usage(1);
>> + break;
>> +
>> + case ':':
>> + if (optopt < CHAR_MAX)
>> + errorf("Option '-%c' requires an argument\n",
>> + optopt);
>> + else
>> + errorf("Option '%s' requires an argument\n",
>> + argv[optind - 1]);
>> + print_usage(1);
>> + break;
>> +
>> + default:
>> + opt = find_option_by_val(c);
>> + if (!opt) {
>> + errorf("Shouldn't have gotten here: "
>> + "option '-%c'\n", c);
>> + print_usage(1);
>> + }
>> +
>> + if (optarg)
>> + opt->opt_private = (void *)optarg;
>> +
>> + break;
>> + }
>> +
>> + if (opt->opt_set) {
>> + errorf("Option '-%c' specified more than once\n",
>> + c);
>> + print_usage(1);
>> + }
>> +
>> + opt->opt_set = 1;
>> + /*
>> + * Handlers for simple options such as showing version,
>> + * printing the usage, or specify the coherency etc.
>> + */
>> + if (opt->opt_handler) {
>> + if (opt->opt_handler(opt, optarg))
>> + print_usage(1);
>> + }
>> +
>> + /*
>> + * Real operation will be added to a list to run later.
>> + */
>> + if (opt->opt_op) {
>> + opt->opt_op->to_private = opt->opt_private;
>> + err = o2info_append_task(opt->opt_op);
>> + if (err)
>> + goto out;
>> + }
>> + }
>> +
>> + if (optind == 1)
>> + print_usage(1);
>> +
>> + if (optind >= argc) {
>> + errorf("No device or file specified\n");
>> + print_usage(1);
>> + }
>> +
>> + *device_or_file = strdup(argv[optind]);
>> + if (!*device_or_file) {
>> + errorf("No memory for allocation\n");
>> + goto out;
>> + }
>> +
>> + optind++;
>> +
>> + if (optind < argc) {
>> + errorf("Too many arguments\n");
>> + print_usage(1);
>> + }
>> +
>> +out:
>> + if (optstring)
>> + ocfs2_free(&optstring);
>> +
>> + if (long_options)
>> + ocfs2_free(&long_options);
>> +
>> + return err;
>> +}
>> +
>> +static errcode_t o2info_run_task(struct o2info_method *om)
>> +{
>> + struct list_head *p, *n;
>> + struct o2info_op_task *task;
>> +
>> + list_for_each_safe(p, n, &o2info_op_task_list) {
>> + task = list_entry(p, struct o2info_op_task, o2p_list);
>> + task->o2p_task->to_run(task->o2p_task, om,
>> + task->o2p_task->to_private);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static void handle_signal(int caught_sig)
>> +{
>> + int exitp = 0, abortp = 0;
>> + static int segv_already;
>> +
>> + switch (caught_sig) {
>> + case SIGQUIT:
>> + abortp = 1;
>> + /* FALL THROUGH */
>> +
>> + case SIGTERM:
>> + case SIGINT:
>> + case SIGHUP:
>> + errorf("Caught signal %d, exiting\n", caught_sig);
>> + exitp = 1;
>> + break;
>> +
>> + case SIGSEGV:
>> + errorf("Segmentation fault, exiting\n");
>> + exitp = 1;
>> + if (segv_already) {
>> + errorf("Segmentation fault loop detected\n");
>> + abortp = 1;
>> + } else
>> + segv_already = 1;
>> + break;
>> +
>> + default:
>> + errorf("Caught signal %d, ignoring\n", caught_sig);
>> + break;
>> + }
>> +
>> + if (!exitp)
>> + return;
>> +
>> + if (abortp)
>> + abort();
>> +
>> + exit(1);
>> +}
>> +
>> +static int setup_signals(void)
>> +{
>> + int rc = 0;
>> + struct sigaction act;
>> +
>> + act.sa_sigaction = NULL;
>> + sigemptyset(&act.sa_mask);
>> + act.sa_handler = handle_signal;
>> +#ifdef SA_INTERRUPT
>> + act.sa_flags = SA_INTERRUPT;
>> +#endif
>> + rc += sigaction(SIGTERM, &act, NULL);
>> + rc += sigaction(SIGINT, &act, NULL);
>> + rc += sigaction(SIGHUP, &act, NULL);
>> + rc += sigaction(SIGQUIT, &act, NULL);
>> + rc += sigaction(SIGSEGV, &act, NULL);
>> + act.sa_handler = SIG_IGN;
>> + rc += sigaction(SIGPIPE, &act, NULL); /* Get EPIPE instead */
>> +
>> + return rc;
>> +}
>> +
>> +static void o2info_init(const char *argv0)
>> +{
>> + initialize_ocfs_error_table();
>> +
>> + tools_setup_argv0(argv0);
>> +
>> + setbuf(stdout, NULL);
>> + setbuf(stderr, NULL);
>> +
>> + if (setup_signals()) {
>> + errorf("Unable to setup signal handling \n");
>> + exit(1);
>> + }
>> +
>> + /* Default should be cluster-coherency */
>> + no_coherency = 0;
>> +}
>> +
>> +int main(int argc, char *argv[])
>> +{
>> + int rc = 0;
>> +
>> + char *device_or_file = NULL;
>> + static struct o2info_method om;
>> +
>> + o2info_init(argv[0]);
>> + parse_options(argc, argv, &device_or_file);
>> +
>> + rc = o2info_is_device(device_or_file);
>> + if (rc < 0)
>> + goto out;
>> + else
>> + if (rc)
>> + om.om_method = O2INFO_USE_LIBOCFS2;
>> + else
>> + om.om_method = O2INFO_USE_IOCTL;
>> +
>> + strncpy(om.om_path, device_or_file, PATH_MAX);
>> +
>> + rc = o2info_open(&om, 0);
>> + if (rc)
>> + goto out;
>> +
>> + rc = o2info_run_task(&om);
>> + if (rc)
>> + goto out;
>> +
>> + o2info_free_op_task_list();
>> +
>> + rc = o2info_close(&om);
>> +out:
>> + if (device_or_file)
>> + ocfs2_free(&device_or_file);
>> +
>> + return rc;
>> +}
>