/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
  This file is part of systemd.
  Copyright 2010 Lennart Poettering
  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.
  systemd 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
  Lesser General Public License for more details.
  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see .
***/
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "log.h"
#include "strv.h"
#include "util.h"
#include "hashmap.h"
#include "path-util.h"
#include "conf-files.h"
#include "fileio.h"
#include "build.h"
#include "sysctl-util.h"
static char **arg_prefixes = NULL;
static const char conf_file_dirs[] = CONF_DIRS_NULSTR("sysctl");
static int apply_all(Hashmap *sysctl_options) {
        char *property, *value;
        Iterator i;
        int r = 0;
        HASHMAP_FOREACH_KEY(value, property, sysctl_options, i) {
                int k;
                k = sysctl_write(property, value);
                if (k < 0) {
                        log_full_errno(k == -ENOENT ? LOG_DEBUG : LOG_WARNING, k,
                                       "Failed to write '%s' to '%s': %m", value, property);
                        if (r == 0 && k != -ENOENT)
                                r = k;
                }
        }
        return r;
}
static int parse_file(Hashmap *sysctl_options, const char *path, bool ignore_enoent) {
        _cleanup_fclose_ FILE *f = NULL;
        int r;
        assert(path);
        r = search_and_fopen_nulstr(path, "re", NULL, conf_file_dirs, &f);
        if (r < 0) {
                if (ignore_enoent && r == -ENOENT)
                        return 0;
                return log_error_errno(r, "Failed to open file '%s', ignoring: %m", path);
        }
        log_debug("Parsing %s", path);
        while (!feof(f)) {
                char l[LINE_MAX], *p, *value, *new_value, *property, *existing;
                void *v;
                int k;
                if (!fgets(l, sizeof(l), f)) {
                        if (feof(f))
                                break;
                        log_error_errno(errno, "Failed to read file '%s', ignoring: %m", path);
                        return -errno;
                }
                p = strstrip(l);
                if (!*p)
                        continue;
                if (strchr(COMMENTS "\n", *p))
                        continue;
                value = strchr(p, '=');
                if (!value) {
                        log_error("Line is not an assignment in file '%s': %s", path, value);
                        if (r == 0)
                                r = -EINVAL;
                        continue;
                }
                *value = 0;
                value++;
                p = sysctl_normalize(strstrip(p));
                value = strstrip(value);
                if (!strv_isempty(arg_prefixes)) {
                        char **i, *t;
                        STRV_FOREACH(i, arg_prefixes) {
                                t = path_startswith(*i, "/proc/sys/");
                                if (t == NULL)
                                        t = *i;
                                if (path_startswith(p, t))
                                        goto found;
                        }
                        /* not found */
                        continue;
                }
found:
                existing = hashmap_get2(sysctl_options, p, &v);
                if (existing) {
                        if (streq(value, existing))
                                continue;
                        log_debug("Overwriting earlier assignment of %s in file '%s'.", p, path);
                        free(hashmap_remove(sysctl_options, p));
                        free(v);
                }
                property = strdup(p);
                if (!property)
                        return log_oom();
                new_value = strdup(value);
                if (!new_value) {
                        free(property);
                        return log_oom();
                }
                k = hashmap_put(sysctl_options, property, new_value);
                if (k < 0) {
                        log_error_errno(k, "Failed to add sysctl variable %s to hashmap: %m", property);
                        free(property);
                        free(new_value);
                        return k;
                }
        }
        return r;
}
static void help(void) {
        printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
               "Applies kernel sysctl settings.\n\n"
               "  -h --help             Show this help\n"
               "     --version          Show package version\n"
               "     --prefix=PATH      Only apply rules with the specified prefix\n"
               , program_invocation_short_name);
}
static int parse_argv(int argc, char *argv[]) {
        enum {
                ARG_VERSION = 0x100,
                ARG_PREFIX
        };
        static const struct option options[] = {
                { "help",      no_argument,       NULL, 'h'           },
                { "version",   no_argument,       NULL, ARG_VERSION   },
                { "prefix",    required_argument, NULL, ARG_PREFIX    },
                {}
        };
        int c;
        assert(argc >= 0);
        assert(argv);
        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
                switch (c) {
                case 'h':
                        help();
                        return 0;
                case ARG_VERSION:
                        puts(PACKAGE_STRING);
                        puts(SYSTEMD_FEATURES);
                        return 0;
                case ARG_PREFIX: {
                        char *p;
                        /* We used to require people to specify absolute paths
                         * in /proc/sys in the past. This is kinda useless, but
                         * we need to keep compatibility. We now support any
                         * sysctl name available. */
                        sysctl_normalize(optarg);
                        if (startswith(optarg, "/proc/sys"))
                                p = strdup(optarg);
                        else
                                p = strappend("/proc/sys/", optarg);
                        if (!p)
                                return log_oom();
                        if (strv_consume(&arg_prefixes, p) < 0)
                                return log_oom();
                        break;
                }
                case '?':
                        return -EINVAL;
                default:
                        assert_not_reached("Unhandled option");
                }
        return 1;
}
int main(int argc, char *argv[]) {
        int r = 0, k;
        Hashmap *sysctl_options;
        r = parse_argv(argc, argv);
        if (r <= 0)
                return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
        log_set_target(LOG_TARGET_AUTO);
        log_parse_environment();
        log_open();
        umask(0022);
        sysctl_options = hashmap_new(&string_hash_ops);
        if (!sysctl_options) {
                r = log_oom();
                goto finish;
        }
        r = 0;
        if (argc > optind) {
                int i;
                for (i = optind; i < argc; i++) {
                        k = parse_file(sysctl_options, argv[i], false);
                        if (k < 0 && r == 0)
                                r = k;
                }
        } else {
                _cleanup_strv_free_ char **files = NULL;
                char **f;
                r = conf_files_list_nulstr(&files, ".conf", NULL, conf_file_dirs);
                if (r < 0) {
                        log_error_errno(r, "Failed to enumerate sysctl.d files: %m");
                        goto finish;
                }
                STRV_FOREACH(f, files) {
                        k = parse_file(sysctl_options, *f, true);
                        if (k < 0 && r == 0)
                                r = k;
                }
        }
        k = apply_all(sysctl_options);
        if (k < 0 && r == 0)
                r = k;
finish:
        hashmap_free_free_free(sysctl_options);
        strv_free(arg_prefixes);
        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}