// SPDX-License-Identifier: GPL-2.0-only
/*
 * Implementation of get_cpuid().
 *
 * Copyright IBM Corp. 2014, 2018
 * Author(s): Alexander Yarygin <yarygin@linux.vnet.ibm.com>
 *            Thomas Richter <tmricht@linux.vnet.ibm.com>
 */

#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
#include <linux/zalloc.h>

#include "../../util/header.h"

#define SYSINFO_MANU    "Manufacturer:"
#define SYSINFO_TYPE    "Type:"
#define SYSINFO_MODEL   "Model:"
#define SRVLVL_CPUMF    "CPU-MF:"
#define SRVLVL_VERSION  "version="
#define SRVLVL_AUTHORIZATION    "authorization="
#define SYSINFO         "/proc/sysinfo"
#define SRVLVL          "/proc/service_levels"

int get_cpuid(char *buffer, size_t sz, struct perf_cpu cpu __maybe_unused)
{
        char *cp, *line = NULL, *line2;
        char type[8], model[33], version[8], manufacturer[32], authorization[8];
        int tpsize = 0, mdsize = 0, vssize = 0, mfsize = 0, atsize = 0;
        int read;
        unsigned long line_sz;
        size_t nbytes;
        FILE *sysinfo;

        /*
         * Scan /proc/sysinfo line by line and read out values for
         * Manufacturer:, Type: and Model:, for example:
         * Manufacturer:    IBM
         * Type:            2964
         * Model:           702              N96
         * The first word is the Model Capacity and the second word is
         * Model (can be omitted). Both words have a maximum size of 16
         * bytes.
         */
        memset(manufacturer, 0, sizeof(manufacturer));
        memset(type, 0, sizeof(type));
        memset(model, 0, sizeof(model));
        memset(version, 0, sizeof(version));
        memset(authorization, 0, sizeof(authorization));

        sysinfo = fopen(SYSINFO, "r");
        if (sysinfo == NULL)
                return errno;

        while ((read = getline(&line, &line_sz, sysinfo)) != -1) {
                if (!strncmp(line, SYSINFO_MANU, strlen(SYSINFO_MANU))) {
                        line2 = line + strlen(SYSINFO_MANU);

                        while ((cp = strtok_r(line2, "\n ", &line2))) {
                                mfsize += scnprintf(manufacturer + mfsize,
                                                    sizeof(manufacturer) - mfsize, "%s", cp);
                        }
                }

                if (!strncmp(line, SYSINFO_TYPE, strlen(SYSINFO_TYPE))) {
                        line2 = line + strlen(SYSINFO_TYPE);

                        while ((cp = strtok_r(line2, "\n ", &line2))) {
                                tpsize += scnprintf(type + tpsize,
                                                    sizeof(type) - tpsize, "%s", cp);
                        }
                }

                if (!strncmp(line, SYSINFO_MODEL, strlen(SYSINFO_MODEL))) {
                        line2 = line + strlen(SYSINFO_MODEL);

                        while ((cp = strtok_r(line2, "\n ", &line2))) {
                                mdsize += scnprintf(model + mdsize, sizeof(model) - mdsize,
                                                    "%s%s", model[0] ? "," : "", cp);
                        }
                        break;
                }
        }
        fclose(sysinfo);

        /* Missing manufacturer, type or model information should not happen */
        if (!manufacturer[0] || !type[0] || !model[0])
                return EINVAL;

        /*
         * Scan /proc/service_levels and return the CPU-MF counter facility
         * version number and authorization level.
         * Optional, does not exist on z/VM guests.
         */
        sysinfo = fopen(SRVLVL, "r");
        if (sysinfo == NULL)
                goto skip_sysinfo;
        while ((read = getline(&line, &line_sz, sysinfo)) != -1) {
                if (strncmp(line, SRVLVL_CPUMF, strlen(SRVLVL_CPUMF)))
                        continue;

                line2 = line + strlen(SRVLVL_CPUMF);
                while ((cp = strtok_r(line2, "\n ", &line2))) {
                        if (!strncmp(cp, SRVLVL_VERSION,
                                     strlen(SRVLVL_VERSION))) {
                                char *sep = strchr(cp, '=');

                                vssize += scnprintf(version + vssize,
                                                    sizeof(version) - vssize, "%s", sep + 1);
                        }
                        if (!strncmp(cp, SRVLVL_AUTHORIZATION,
                                     strlen(SRVLVL_AUTHORIZATION))) {
                                char *sep = strchr(cp, '=');

                                atsize += scnprintf(authorization + atsize,
                                                    sizeof(authorization) - atsize, "%s", sep + 1);
                        }
                }
        }
        fclose(sysinfo);

skip_sysinfo:
        free(line);

        if (version[0] && authorization[0] )
                nbytes = snprintf(buffer, sz, "%s,%s,%s,%s,%s",
                                  manufacturer, type, model, version,
                                  authorization);
        else
                nbytes = snprintf(buffer, sz, "%s,%s,%s", manufacturer, type,
                                  model);
        return (nbytes >= sz) ? ENOBUFS : 0;
}

char *get_cpuid_str(struct perf_cpu cpu)
{
        char *buf = malloc(128);

        if (buf && get_cpuid(buf, 128, cpu))
                zfree(&buf);
        return buf;
}