add server for realtime monitoring and parameters changing

modbus_params/server.c

@@ -0,0 +1,122 @@
+/*
+ * This file is part of the modbus_param project.
+ * Copyright 2025 Edward V. Emelianov <edward.emelianoff@gmail.com>.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "server.h"
+#include "modbus.h"
+
+static sl_sock_t *s = NULL;
+
+// stop dump and close dump file
+static sl_sock_hresult_e closedump(_U_ sl_sock_t *client, _U_ sl_sock_hitem_t *item, _U_ const char *req){
+    closedumpfile();
+    return RESULT_OK;
+}
+// open new dump file
+static sl_sock_hresult_e newdump(sl_sock_t *client, _U_ sl_sock_hitem_t *item, const char *req){
+    char buf[BUFSIZ];
+    if(!req){ // getter
+        snprintf(buf, BUFSIZ-1, "%s = %s\n", item->key, getdumpname());
+        sl_sock_sendstrmessage(client, buf);
+        return RESULT_SILENCE;
+    }else{
+        if(!opendumpfile(req) || !rundump()) return RESULT_FAIL;
+    }
+    return RESULT_OK;
+}
+
+static sl_sock_hitem_t handlers[] = {
+    {closedump, "clodump", "stop dump and close current dump file", NULL},
+    {newdump, "newdump", "open new dump file or get name of current", NULL},
+    {NULL, NULL, NULL, NULL}
+};
+
+// new connections handler (return FALSE to reject client)
+static int connected(sl_sock_t *c){
+    if(c->type == SOCKT_UNIX) LOGMSG("New client fd=%d connected", c->fd);
+    else LOGMSG("New client fd=%d, IP=%s connected", c->fd, c->IP);
+    return TRUE;
+}
+// disconnected handler
+static void disconnected(sl_sock_t *c){
+    if(c->type == SOCKT_UNIX) LOGMSG("Disconnected client fd=%d", c->fd);
+    else LOGMSG("Disconnected client fd=%d, IP=%s", c->fd, c->IP);
+}
+
+static sl_sock_hresult_e defhandler(sl_sock_t *s, const char *str){
+    if(!s || !str) return RESULT_FAIL;
+    char key[SL_KEY_LEN], value[SL_VAL_LEN];
+    int n = sl_get_keyval(str, key, value);
+    if(n == 0){
+        WARNX("Can't parse `%s` as reg[=val]", str);
+        return RESULT_BADKEY;
+    }
+    dicentry_t *entry = NULL;
+    int N;
+    if(sl_str2i(&N, key)){ // `key` is register number
+        entry = findentry_by_reg((uint16_t) N);
+    }else{ // `key` is register name
+        entry = findentry_by_code(key);
+    }
+    if(!entry){
+        WARNX("Entry %s not found", key);
+        return RESULT_BADKEY;
+    }
+    if(n == 1){ // getter
+        if(!read_entry(entry)) return RESULT_BADKEY;
+        snprintf(value, SL_VAL_LEN-1, "%s=%u\n", key, entry->value);
+    }else{ // setter
+        if(!sl_str2i(&N, value)){
+            WARNX("%s isn't a value of register", value);
+            return RESULT_BADVAL;
+        }
+        entry->value = (uint16_t)N;
+        if(!write_entry(entry)) return RESULT_FAIL;
+        return RESULT_OK;
+    }
+    sl_sock_sendstrmessage(s, value);
+    return RESULT_SILENCE;
+}
+
+int runserver(const char *node, int isunix){
+    if(!node){
+        WARNX("Point node");
+        return FALSE;
+    }
+    sl_socktype_e type = (isunix) ? SOCKT_UNIX : SOCKT_NET;
+    if(s) sl_sock_delete(&s);
+    s = sl_sock_run_server(type, node, -1, handlers);
+    if(!s){
+        WARNX("Can't run server");
+        return FALSE;
+    }
+    sl_sock_connhandler(s, connected);
+    sl_sock_dischandler(s, disconnected);
+    sl_sock_defmsghandler(s, defhandler);
+    while(s && s->connected){
+        if(!s->rthread){
+            WARNX("Server handlers thread is dead");
+            break;
+        }
+    }
+    DBG("Close");
+    sl_sock_delete(&s);
+    return TRUE;
+}