// SPDX-License-Identifier: GPL-2.0-only
/*
 *  (C) 2010,2011       Thomas Renninger <trenn@suse.de>, Novell Inc.
 *
 *  Ideas taken over from the perf userspace tool (included in the Linus
 *  kernel git repo): subcommand builtins and param parsing.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sched.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/utsname.h>

#include "builtin.h"
#include "helpers/helpers.h"
#include "helpers/bitmask.h"

#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))

static int cmd_help(int argc, const char **argv);

/* Global cpu_info object available for all binaries
 * Info only retrieved from CPU 0
 *
 * Values will be zero/unknown on non X86 archs
 */
struct cpupower_cpu_info cpupower_cpu_info;
int run_as_root;
int base_cpu;
/* Affected cpus chosen by -c/--cpu param */
struct bitmask *cpus_chosen;
struct bitmask *online_cpus;
struct bitmask *offline_cpus;

#ifdef DEBUG
int be_verbose;
#endif

static void print_help(void);

struct cmd_struct {
        const char *cmd;
        int (*main)(int, const char **);
        int needs_root;
};

static struct cmd_struct commands[] = {
        { "frequency-info",     cmd_freq_info,  0       },
        { "frequency-set",      cmd_freq_set,   1       },
        { "idle-info",          cmd_idle_info,  0       },
        { "idle-set",           cmd_idle_set,   1       },
        { "powercap-info",      cmd_cap_info,   0       },
        { "set",                cmd_set,        1       },
        { "info",               cmd_info,       0       },
        { "monitor",            cmd_monitor,    0       },
        { "help",               cmd_help,       0       },
        /*      { "bench",      cmd_bench,      1       }, */
};

static void print_help(void)
{
        unsigned int i;

#ifdef DEBUG
        printf(_("Usage:\tcpupower [-d|--debug] [-c|--cpu cpulist ] <command> [<args>]\n"));
#else
        printf(_("Usage:\tcpupower [-c|--cpu cpulist ] <command> [<args>]\n"));
#endif
        printf(_("Supported commands are:\n"));
        for (i = 0; i < ARRAY_SIZE(commands); i++)
                printf("\t%s\n", commands[i].cmd);
        printf(_("\nNot all commands can make use of the -c cpulist option.\n"));
        printf(_("\nUse 'cpupower help <command>' for getting help for above commands.\n"));
}

static int print_man_page(const char *subpage)
{
        int len;
        char *page;

        len = 10; /* enough for "cpupower-" */
        if (subpage != NULL)
                len += strlen(subpage);

        page = malloc(len);
        if (!page)
                return -ENOMEM;

        sprintf(page, "cpupower");
        if ((subpage != NULL) && strcmp(subpage, "help")) {
                strcat(page, "-");
                strcat(page, subpage);
        }

        execlp("man", "man", page, NULL);

        /* should not be reached */
        return -EINVAL;
}

static int cmd_help(int argc, const char **argv)
{
        if (argc > 1) {
                print_man_page(argv[1]); /* exits within execlp() */
                return EXIT_FAILURE;
        }

        print_help();
        return EXIT_SUCCESS;
}

static void print_version(void)
{
        printf(PACKAGE " " VERSION "\n");
        printf(_("Report errors and bugs to %s, please.\n"), PACKAGE_BUGREPORT);
}

static void handle_options(int *argc, const char ***argv)
{
        int ret, x, new_argc = 0;

        if (*argc < 1)
                return;

        for (x = 0;  x < *argc && ((*argv)[x])[0] == '-'; x++) {
                const char *param = (*argv)[x];
                if (!strcmp(param, "-h") || !strcmp(param, "--help")) {
                        print_help();
                        exit(EXIT_SUCCESS);
                } else if (!strcmp(param, "-c") || !strcmp(param, "--cpu")) {
                        if (*argc < 2) {
                                print_help();
                                exit(EXIT_FAILURE);
                        }
                        if (!strcmp((*argv)[x+1], "all"))
                                bitmask_setall(cpus_chosen);
                        else {
                                ret = bitmask_parselist(
                                                (*argv)[x+1], cpus_chosen);
                                if (ret < 0) {
                                        fprintf(stderr, _("Error parsing cpu "
                                                          "list\n"));
                                        exit(EXIT_FAILURE);
                                }
                        }
                        x += 1;
                        /* Cut out param: cpupower -c 1 info -> cpupower info */
                        new_argc += 2;
                        continue;
                } else if (!strcmp(param, "-v") ||
                        !strcmp(param, "--version")) {
                        print_version();
                        exit(EXIT_SUCCESS);
#ifdef DEBUG
                } else if (!strcmp(param, "-d") || !strcmp(param, "--debug")) {
                        be_verbose = 1;
                        new_argc++;
                        continue;
#endif
                } else {
                        fprintf(stderr, "Unknown option: %s\n", param);
                        print_help();
                        exit(EXIT_FAILURE);
                }
        }
        *argc -= new_argc;
        *argv += new_argc;
}

int main(int argc, const char *argv[])
{
        const char *cmd;
        unsigned int i, ret;
        struct stat statbuf;
        struct utsname uts;
        char pathname[32];

        cpus_chosen = bitmask_alloc(sysconf(_SC_NPROCESSORS_CONF));
        online_cpus = bitmask_alloc(sysconf(_SC_NPROCESSORS_CONF));
        offline_cpus = bitmask_alloc(sysconf(_SC_NPROCESSORS_CONF));

        argc--;
        argv += 1;

        handle_options(&argc, &argv);

        cmd = argv[0];

        if (argc < 1) {
                print_help();
                return EXIT_FAILURE;
        }

        setlocale(LC_ALL, "");
        textdomain(PACKAGE);

        /* Turn "perf cmd --help" into "perf help cmd" */
        if (argc > 1 && !strcmp(argv[1], "--help")) {
                argv[1] = argv[0];
                argv[0] = cmd = "help";
        }

        base_cpu = sched_getcpu();
        if (base_cpu < 0) {
                fprintf(stderr, _("No valid cpus found.\n"));
                return EXIT_FAILURE;
        }

        get_cpu_info(&cpupower_cpu_info);
        run_as_root = !geteuid();
        if (run_as_root) {
                ret = uname(&uts);
                sprintf(pathname, "/dev/cpu/%d/msr", base_cpu);
                if (!ret && !strcmp(uts.machine, "x86_64") &&
                    stat(pathname, &statbuf) != 0) {
                        if (system("modprobe msr") == -1)
        fprintf(stderr, _("MSR access not available.\n"));
                }
        }

        for (i = 0; i < ARRAY_SIZE(commands); i++) {
                struct cmd_struct *p = commands + i;
                if (strcmp(p->cmd, cmd))
                        continue;
                if (!run_as_root && p->needs_root) {
                        fprintf(stderr, _("Subcommand %s needs root "
                                          "privileges\n"), cmd);
                        return EXIT_FAILURE;
                }
                ret = p->main(argc, argv);
                if (cpus_chosen)
                        bitmask_free(cpus_chosen);
                if (online_cpus)
                        bitmask_free(online_cpus);
                if (offline_cpus)
                        bitmask_free(offline_cpus);
                return ret;
        }
        print_help();
        return EXIT_FAILURE;
}