// SPDX-License-Identifier: GPL-2.0
#include <stdbool.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <stdio.h>
#include "util/debug.h"
#include <dwarf-regs.h>
#include <subcmd/parse-options.h>
#include "util/perf_regs.h"
#include "util/parse-regs-options.h"

static void list_perf_regs(FILE *fp, uint64_t mask)
{
        const char *last_name = NULL;

        fprintf(fp, "available registers: ");
        for (int reg = 0; reg < 64; reg++) {
                const char *name;

                if (((1ULL << reg) & mask) == 0)
                        continue;

                name = perf_reg_name(reg, EM_HOST, EF_HOST);
                if (name && (!last_name || strcmp(last_name, name)))
                        fprintf(fp, "%s%s", reg > 0 ? " " : "", name);
                last_name = name;
        }
        fputc('\n', fp);
}

static uint64_t name_to_perf_reg_mask(const char *to_match, uint64_t mask)
{
        uint64_t reg_mask = 0;

        for (int reg = 0; reg < 64; reg++) {
                const char *name;

                if (((1ULL << reg) & mask) == 0)
                        continue;

                name = perf_reg_name(reg, EM_HOST, EF_HOST);
                if (!name)
                        continue;

                if (!strcasecmp(to_match, name))
                        reg_mask |= 1ULL << reg;
        }
        return reg_mask;
}

static int
__parse_regs(const struct option *opt, const char *str, int unset, bool intr)
{
        uint64_t *mode = (uint64_t *)opt->value;
        char *s, *os = NULL, *p;
        int ret = -1;
        uint64_t mask;

        if (unset)
                return 0;

        /*
         * cannot set it twice
         */
        if (*mode)
                return -1;

        mask = intr ? perf_intr_reg_mask(EM_HOST) : perf_user_reg_mask(EM_HOST);

        /* str may be NULL in case no arg is passed to -I */
        if (!str) {
                *mode = mask;
                return 0;
        }

        /* because str is read-only */
        s = os = strdup(str);
        if (!s)
                return -1;

        for (;;) {
                uint64_t reg_mask;

                p = strchr(s, ',');
                if (p)
                        *p = '\0';

                if (!strcmp(s, "?")) {
                        list_perf_regs(stderr, mask);
                        goto error;
                }

                reg_mask = name_to_perf_reg_mask(s, mask);
                if (reg_mask == 0) {
                        ui__warning("Unknown register \"%s\", check man page or run \"perf record %s?\"\n",
                                s, intr ? "-I" : "--user-regs=");
                        goto error;
                }
                *mode |= reg_mask;

                if (!p)
                        break;

                s = p + 1;
        }
        ret = 0;

error:
        free(os);
        return ret;
}

int
parse_user_regs(const struct option *opt, const char *str, int unset)
{
        return __parse_regs(opt, str, unset, false);
}

int
parse_intr_regs(const struct option *opt, const char *str, int unset)
{
        return __parse_regs(opt, str, unset, true);
}