builtin-config.c

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// SPDX-License-Identifier: GPL-2.0
/*
 * builtin-config.c
 *
 * Copyright (C) 2015, Taeung Song <treeze.taeung@gmail.com>
 *
 */
#include "builtin.h"

#include "perf.h"

#include "util/cache.h"
#include <subcmd/parse-options.h>
#include "util/util.h"
#include "util/debug.h"
#include "util/config.h"
#include <linux/string.h>

static bool use_system_config, use_user_config;

static const char * const config_usage[] = {
    "perf config [<file-option>] [options] [section.name[=value] ...]",
    NULL
};

enum actions {
    ACTION_LIST = 1
} actions;

static struct option config_options[] = {
    OPT_SET_UINT('l', "list", &actions,
             "show current config variables", ACTION_LIST),
    OPT_BOOLEAN(0, "system", &use_system_config, "use system config file"),
    OPT_BOOLEAN(0, "user", &use_user_config, "use user config file"),
    OPT_END()
};

static int set_config(struct perf_config_set *set, const char *file_name)
{
    struct perf_config_section *section = NULL;
    struct perf_config_item *item = NULL;
    const char *first_line = "# this file is auto-generated.";
    FILE *fp;

    if (set == NULL)
        return -1;

    fp = fopen(file_name, "w");
    if (!fp)
        return -1;

    fprintf(fp, "%s\n", first_line);

    /* overwrite configvariables */
    perf_config_items__for_each_entry(&set->sections, section) {
        if (!use_system_config && section->from_system_config)
            continue;
        fprintf(fp, "[%s]\n", section->name);

        perf_config_items__for_each_entry(&section->items, item) {
            if (!use_system_config && item->from_system_config)
                continue;
            if (item->value)
                fprintf(fp, "\t%s = %s\n",
                    item->name, item->value);
        }
    }
    fclose(fp);

    return 0;
}

static int show_spec_config(struct perf_config_set *set, const char *var)
{
    struct perf_config_section *section;
    struct perf_config_item *item;

    if (set == NULL)
        return -1;

    perf_config_items__for_each_entry(&set->sections, section) {
        if (!strstarts(var, section->name))
            continue;

        perf_config_items__for_each_entry(&section->items, item) {
            const char *name = var + strlen(section->name) + 1;

            if (strcmp(name, item->name) == 0) {
                char *value = item->value;

                if (value) {
                    printf("%s=%s\n", var, value);
                    return 0;
                }
            }

        }
    }

    return 0;
}

static int show_config(struct perf_config_set *set)
{
    struct perf_config_section *section;
    struct perf_config_item *item;

    if (set == NULL)
        return -1;

    perf_config_set__for_each_entry(set, section, item) {
        char *value = item->value;

        if (value)
            printf("%s.%s=%s\n", section->name,
                   item->name, value);
    }

    return 0;
}

static int parse_config_arg(char *arg, char **var, char **value)
{
    const char *last_dot = strchr(arg, '.');

    /*
     * Since "var" actually contains the section name and the real
     * config variable name separated by a dot, we have to know where the dot is.
     */
    if (last_dot == NULL || last_dot == arg) {
        pr_err("The config variable does not contain a section name: %s\n", arg);
        return -1;
    }
    if (!last_dot[1]) {
        pr_err("The config variable does not contain a variable name: %s\n", arg);
        return -1;
    }

    *value = strchr(arg, '=');
    if (*value == NULL)
        *var = arg;
    else if (!strcmp(*value, "=")) {
        pr_err("The config variable does not contain a value: %s\n", arg);
        return -1;
    } else {
        *value = *value + 1; /* excluding a first character '=' */
        *var = strsep(&arg, "=");
        if (*var[0] == '\0') {
            pr_err("invalid config variable: %s\n", arg);
            return -1;
        }
    }

    return 0;
}

int cmd_config(int argc, const char **argv)
{
    int i, ret = -1;
    struct perf_config_set *set;
    char *user_config = mkpath("%s/.perfconfig", getenv("HOME"));
    const char *config_filename;
    bool changed = false;

    argc = parse_options(argc, argv, config_options, config_usage,
                 PARSE_OPT_STOP_AT_NON_OPTION);

    if (use_system_config && use_user_config) {
        pr_err("Error: only one config file at a time\n");
        parse_options_usage(config_usage, config_options, "user", 0);
        parse_options_usage(NULL, config_options, "system", 0);
        return -1;
    }

    if (use_system_config)
        config_exclusive_filename = perf_etc_perfconfig();
    else if (use_user_config)
        config_exclusive_filename = user_config;

    if (!config_exclusive_filename)
        config_filename = user_config;
    else
        config_filename = config_exclusive_filename;

    /*
     * At only 'config' sub-command, individually use the config set
     * because of reinitializing with options config file location.
     */
    set = perf_config_set__new();
    if (!set)
        goto out_err;

    switch (actions) {
    case ACTION_LIST:
        if (argc) {
            pr_err("Error: takes no arguments\n");
            parse_options_usage(config_usage, config_options, "l", 1);
        } else {
            if (show_config(set) < 0) {
                pr_err("Nothing configured, "
                       "please check your %s \n", config_filename);
                goto out_err;
            }
        }
        break;
    default:
        if (!argc) {
            usage_with_options(config_usage, config_options);
            break;
        }

        for (i = 0; argv[i]; i++) {
            char *var, *value;
            char *arg = strdup(argv[i]);

            if (!arg) {
                pr_err("%s: strdup failed\n", __func__);
                goto out_err;
            }

            if (parse_config_arg(arg, &var, &value) < 0) {
                free(arg);
                goto out_err;
            }

            if (value == NULL) {
                if (show_spec_config(set, var) < 0) {
                    pr_err("%s is not configured: %s\n",
                           var, config_filename);
                    free(arg);
                    goto out_err;
                }
            } else {
                if (perf_config_set__collect(set, config_filename,
                                 var, value) < 0) {
                    pr_err("Failed to add '%s=%s'\n",
                           var, value);
                    free(arg);
                    goto out_err;
                }
                changed = true;
            }
            free(arg);
        }

        if (!changed)
            break;

        if (set_config(set, config_filename) < 0) {
            pr_err("Failed to set the configs on %s\n",
                   config_filename);
            goto out_err;
        }
    }

    ret = 0;
out_err:
    perf_config_set__delete(set);
    return ret;
}