summaryrefslogtreecommitdiff
path: root/src/tool/eathena-monitor.cpp
blob: f6e8271b34c6347150fb3ba671fab4819baace5b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/**
 * Name:    eAthena processes monitor
 * Original Author:  Bartosz Waszak <waszi@evil.org.pl>
 * Rewrite Author: Ben Longbons <b.r.longbons@gmail.com>
 * License: GPL
 * Compilation:
 * gcc -o eathena-monitor eathena-monitor.c
 */

#include <sys/wait.h>

#include <fcntl.h>
#include <unistd.h>

#include <csignal>

#include <fstream>

#include "../common/cxxstdio.hpp"
#include "../common/io.hpp"
#include "../common/utils.hpp"

#include "../poison.hpp"

#define LOGIN_SERVER "./login-server"
#define MAP_SERVER "./map-server"
#define CHAR_SERVER "./char-server"
#define CONFIG "conf/eathena-monitor.conf"


// initialiized to $HOME/tmwserver
static
FString workdir;
//the rest are relative to workdir
static
FString login_server = LOGIN_SERVER;
static
FString map_server = MAP_SERVER;
static
FString char_server = CHAR_SERVER;

static
pid_t pid_login, pid_map, pid_char;

static
FString make_path(XString base, XString path)
{
    MString m;
    m += base;
    m += '/';
    m += path;
    return FString(m);
}

static
void parse_option(XString name, ZString value)
{
    if (name == "login_server")
        login_server = value;
    else if (name == "map_server")
        map_server = value;
    else if (name == "char_server")
        char_server = value;
    else if (name == "workdir")
        workdir = value;
    else
    {
        FString name_ = name;
        FPRINTF(stderr, "WARNING: ingnoring invalid option '%s' : '%s'\n",
                name_, value);
    }
}

static
void read_config(ZString filename)
{
    std::ifstream in(filename.c_str());
    if (!in.is_open())
    {
        FPRINTF(stderr, "Monitor config file not found: %s\n", filename);
        exit(1);
    }

    FString line;
    while (io::getline(in, line))
    {
        SString name;
        TString value;
        if (!split_key_value(line, &name, &value))
            continue;

        parse_option(name, value);
    }
}

static
pid_t start_process(ZString exec)
{
    const char *args[2] = {exec.c_str(), NULL};
    pid_t pid = fork();
    if (pid == -1)
    {
        FPRINTF(stderr, "Failed to fork");
        return 0;
    }
    if (pid == 0)
    {
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wcast-qual"
        execv(exec.c_str(), const_cast<char **>(args));
#pragma GCC diagnostic pop
        perror("Failed to exec");
        kill(getppid(), SIGABRT);
        exit(1);
    }
    return pid;
}

// Kill all children with the same signal we got, then ourself.
static
void stop_process(int sig)
{
    if (pid_map)
        kill(pid_map, sig);
    if (pid_login)
        kill(pid_login, sig);
    if (pid_char)
        kill(pid_char, sig);
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wold-style-cast"
    signal(sig, SIG_DFL);
#pragma GCC diagnostic pop
    raise(sig);
}

int main(int argc, char *argv[])
{
    // These are all the signals we are likely to get
    // The shell handles stop/cont
    signal(SIGTERM, stop_process);
    signal(SIGINT, stop_process);
    signal(SIGQUIT, stop_process);
    signal(SIGABRT, stop_process);

    workdir = make_path(ZString(ZString::really_construct_from_a_pointer, getenv("HOME"), nullptr), "tmwserver");

    ZString config = CONFIG;
    if (argc > 1)
        config = ZString(ZString::really_construct_from_a_pointer, argv[1], nullptr);
    read_config(config);

    if (chdir(workdir.c_str()) < 0)
    {
        perror("Failed to change directory");
        exit(1);
    }

    PRINTF("Starting:\n");
    PRINTF("* workdir: %s\n",  workdir);
    PRINTF("* login_server: %s\n", login_server);
    PRINTF("* map_server: %s\n", map_server);
    PRINTF("* char_server: %s\n", char_server);
    {
        //make sure all possible file descriptors are free for use by the servers
        //if there are file descriptors higher than the max open from before the limit dropped, that's not our problem
        int fd = sysconf(_SC_OPEN_MAX);
        while (--fd > 2)
           if (close(fd) == 0)
               FPRINTF(stderr, "close fd %d\n", fd);
        fd = open("/dev/null", O_RDWR);
        if (fd < 0)
        {
            perror("open /dev/null");
            exit(1);
        }
        dup2(fd, 0);
        dup2(fd, 1);
        close(fd);
    }
    while (1)
    {
        // write stuff to stderr
        timestamp_seconds_buffer timestamp;
        stamp_time(timestamp);

        if (!pid_login)
        {
            pid_login = start_process(login_server);
            FPRINTF(stderr, "[%s] forked login server: %lu\n",
                    timestamp, static_cast<unsigned long>(pid_login));
        }
        if (!pid_char)
        {
            pid_char = start_process(char_server);
            FPRINTF(stderr, "[%s] forked char server: %lu\n",
                    timestamp, static_cast<unsigned long>(pid_char));
        }
        if (!pid_map)
        {
            pid_map = start_process(map_server);
            FPRINTF(stderr, "[%s] forked map server: %lu\n",
                    timestamp, static_cast<unsigned long>(pid_map));
        }
        pid_t dead = wait(NULL);
        if (dead == -1)
        {
            perror("Failed to wait for child");
            exit(1);
        }
        if (pid_login == dead)
            pid_login = 0;
        if (pid_char == dead)
            pid_char = 0;
        if (pid_map == dead)
            pid_map = 0;
    }
}