--- a/src/mapsearch.c	Wed Jun 21 01:46:51 2023 +0300
+++ b/src/mapsearch.c	Sun Jul 02 03:44:34 2023 +0300
@@ -151,8 +151,7 @@
         "<filename.map>:<locfilename.loc>:<map/continent name>[:<world x-offset>:<world y-offset>]\n"
         "World offsets are optional and default to 0, 0 if not specified.\n"
         "\n"
-        "All the map offsets are relative to world origin coordinates, which are 0,0 by default.\n"
-        "-w 8192:8192\n"
+        "All the map offsets are relative to world origin, which is 0,0 by default.\n"
     );
 }
 
@@ -218,13 +217,14 @@
 }
 
 
-bool mapParseCoordPair(const char *str, int *xc, int *yc)
+bool argParseCoordPair(const char *str, int *xc, int *yc)
 {
     char *piece, *tmp, *fmt = th_strdup(str);
-    bool ret = false;
+    bool ok = false;
 
     if ((piece = strchr(fmt, ':')) == NULL)
-        goto err;
+        goto out;
+
     *piece++ = 0;
 
     tmp = th_strdup_trim(fmt, TH_TRIM_BOTH);
@@ -235,32 +235,46 @@
     *yc = atoi(tmp);
     th_free(tmp);
 
-    ret = true;
+    ok = true;
 
-err:
+out:
     th_free(fmt);
-    return ret;
+    return ok;
 }
 
 
-bool mapParseMapSpec(const char *str, MAPInfoCtx *info)
+bool argParseMapSpec(const char *cspec)
 {
-    char *piece, *start, *fmt = th_strdup(str);
-    bool ret = false;
+    MAPInfoCtx *info;
+    char *piece, *start, *spec = th_strdup(cspec);
+    bool ok = false;
 
+    if (optNMaps >= SET_MAX_MAPS)
+    {
+        mapERR("Maximum number of map specs already specified.\n");
+        goto out;
+    }
+
+    info = &optMaps[optNMaps];
     memset(info, 0, sizeof(MAPInfoCtx));
 
     // Check for map filename end
-    if ((piece = strchr(fmt, ':')) == NULL)
-        goto err;
+    if ((piece = strchr(spec, ':')) == NULL)
+    {
+        mapERR("Invalid map spec '%s': missing map filename separator ':'.\n", cspec);
+        goto out;
+    }
     *piece++ = 0;
 
-    info->mapFilename = th_strdup_trim(fmt, TH_TRIM_BOTH);
+    info->mapFilename = th_strdup_trim(spec, TH_TRIM_BOTH);
     start = piece;
 
     // Check for loc filename end
     if ((piece = strchr(start, ':')) == NULL)
-        goto err;
+    {
+        mapERR("Invalid map spec '%s': missing loc filename separator ':'.\n", cspec);
+        goto out;
+    }
     *piece++ = 0;
 
     info->locFile.filename = th_strdup_trim(start, TH_TRIM_BOTH);
@@ -274,14 +288,17 @@
 
     // Get world X/Y offsets, if any
     if (piece != NULL &&
-        !mapParseCoordPair(piece, &info->locFile.xoffs, &info->locFile.yoffs))
-        goto err;
+        !argParseCoordPair(piece, &info->locFile.xoffs, &info->locFile.yoffs))
+    {
+        mapERR("Invalid map spec '%s': invalid coordinate offsets '%s'.\n", cspec, piece);
+        goto out;
+    }
 
-    ret = true;
+    ok = true;
 
-err:
-    th_free(fmt);
-    return ret;
+out:
+    th_free(spec);
+    return ok;
 }
 
 
@@ -291,7 +308,7 @@
 }
 
 
-void mapFreeListenCtxR(MAPListenerCtx *ctx)
+void mapFreeListenCtx(MAPListenerCtx *ctx)
 {
     if (ctx != NULL)
     {
@@ -300,35 +317,38 @@
         th_free(ctx->sslCertFile);
         th_free(ctx->sslKeyFile);
         th_free(ctx->sslCAFile);
+        th_free(ctx);
     }
 }
 
 
-void mapFreeListenCtx(MAPListenerCtx *ctx)
+bool argParseListenerSpec(const char *cspec)
 {
-    mapFreeListenCtxR(ctx);
-    th_free(ctx);
-}
-
+    MAPListenerCtx *ctx = NULL;
+    char *start, *end, *flags, *interface,
+         *port = NULL, *spec = th_strdup(cspec);
+    bool ok = false;
 
-MAPListenerCtx *mapParseListenerSpec(const char *cfmt)
-{
-    char *start, *end, *flags, *port = NULL,
-         *interface, *fmt = th_strdup(cfmt);
-    bool ret = false;
-    MAPListenerCtx *ctx;
+    if (optNListenTo >= SET_MAX_LISTEN)
+    {
+        mapERR("Maximum number of listener specs already specified.\n");
+        goto out;
+    }
 
     if ((ctx = mapNewListenCtx()) == NULL)
+    {
+        mapERR("Could not allocate memory for listener spec!\n");
         goto out;
+    }
 
-    interface = fmt;
+    interface = spec;
     if (*interface == '[')
     {
         // IPv6 IP address is handled in a special case
         interface++;
         if ((end = strchr(interface, ']')) == NULL)
         {
-            mapERR("Invalid IPv6 IP address '%s'.\n", cfmt);
+            mapERR("Invalid IPv6 IP address '%s'.\n", cspec);
             goto out;
         }
         *end++ = 0;
@@ -348,7 +368,7 @@
     // Find port number separator
     if (end == NULL || *end != ':')
     {
-        mapERR("Missing listening port in '%s'.\n", cfmt);
+        mapERR("Missing listening port in '%s'.\n", cspec);
         goto out;
     }
     *end++ = 0;
@@ -381,12 +401,12 @@
     // Get port number
     if ((port = th_strdup_trim(start, TH_TRIM_BOTH)) == NULL)
     {
-        mapERR("Missing listening port in '%s'.\n", cfmt);
+        mapERR("Missing listening port in '%s'.\n", cspec);
         goto out;
     }
     if ((ctx->port = atoi(port)) < 1)
     {
-        mapERR("Invalid listening port %d in '%s'.\n", ctx->port, cfmt);
+        mapERR("Invalid listening port %d in '%s'.\n", ctx->port, cspec);
         goto out;
     }
 
@@ -453,17 +473,52 @@
             goto out;
         }
     }
-    ret = true;
+    ok = true;
 
 out:
-    th_free(fmt);
+    th_free(spec);
     th_free(port);
 
-    if (ret)
-        return ctx;
+    if (ok)
+    {
+        optListenTo[optNListenTo++] = ctx;
+        return true;
+    }
 
     mapFreeListenCtx(ctx);
-    return NULL;
+    return false;
+}
+
+
+bool argParseUID(const char *str, int *val)
+{
+    if (sscanf(str, "%d", val) != 1)
+    {
+        struct passwd *info = getpwnam(str);
+        if (info == NULL)
+        {
+            mapERR("Invalid UID '%s'.\n", str);
+            return false;
+        }
+        *val = info->pw_uid;
+    }
+    return true;
+}
+
+
+bool argParseGID(const char *str, int *val)
+{
+    if (sscanf(str, "%d", val) != 1)
+    {
+        struct group *info = getgrnam(str);
+        if (info == NULL)
+        {
+            mapERR("Invalid GID '%s'.\n", str);
+            return false;
+        }
+        *val = info->gr_gid;
+    }
+    return true;
 }
 
 
@@ -481,27 +536,14 @@
         break;
 
     case 2:
-        if (optNListenTo < SET_MAX_LISTEN)
-        {
-            MAPListenerCtx *ctx;
-            if ((ctx = mapParseListenerSpec(optArg)) != NULL)
-                optListenTo[optNListenTo++] = ctx;
-            else
-                return false;
-        }
-        else
-        {
-            mapERR("Maximum number of listener specs already specified.\n");
-            return false;
-        }
-        break;
+        return argParseListenerSpec(optArg);
 
     case 3:
         optSSLCipherList = optArg;
         break;
 
     case 5:
-        if (!mapParseCoordPair(optArg, &optWorldXC, &optWorldYC))
+        if (!argParseCoordPair(optArg, &optWorldXC, &optWorldYC))
         {
             mapERR("Invalid world origin coordinates '%s'.\n", optArg);
             return false;
@@ -525,32 +567,10 @@
         break;
 
     case 7:
-        if (sscanf(optArg, "%d", &optUID) != 1)
-        {
-            struct passwd *info = getpwnam(optArg);
-            if (info != NULL)
-                optUID = info->pw_uid;
-            else
-            {
-                mapERR("Invalid UID '%s'.\n", optArg);
-                return false;
-            }
-        }
-        break;
+        return argParseUID(optArg, &optUID);
 
     case 8:
-        if (sscanf(optArg, "%d", &optGID) != 1)
-        {
-            struct group *info = getgrnam(optArg);
-            if (info != NULL)
-                optUID = info->gr_gid;
-            else
-            {
-                mapERR("Invalid GID '%s'.\n", optArg);
-                return false;
-            }
-        }
-        break;
+        return argParseGID(optArg, &optGID);
 
     case 9:
         optLogFilename = optArg;
@@ -571,22 +591,7 @@
 
 bool argHandleFile(char *currArg)
 {
-    if (optNMaps < SET_MAX_MAPS)
-    {
-        if (!mapParseMapSpec(currArg, &optMaps[optNMaps]))
-        {
-            mapERR("Invalid map spec '%s'.\n", currArg);
-            return false;
-        }
-
-        optNMaps++;
-        return true;
-    }
-    else
-    {
-        mapERR("Maximum number of map specs already specified.\n");
-        return false;
-    }
+    return argParseMapSpec(currArg);
 }
 
 
@@ -1788,6 +1793,8 @@
 
 int main(int argc, char *argv[])
 {
+    int res = 0;
+
     // Initialize
     th_init("MapSearch", "Map Search WebSockets server", "0.8", NULL, NULL);
     th_verbosity = 0;
@@ -1795,39 +1802,48 @@
     memset(&optMaps, 0, sizeof(optMaps));
     memset(&optListenTo, 0, sizeof(optListenTo));
 
-    // Parse command line arguments
-    bool argsOK = th_args_process(argc, argv, optList, optListN, argHandleOpt, argHandleFile, 0);
+
 
-    if (!argsOK)
-        return -2;
+    // Parse command line arguments
+    if (!th_args_process(argc, argv, optList, optListN,
+        argHandleOpt, argHandleFile, 0))
+    {
+        res = -10;
+        goto out;
+    }
 
     if (optNMaps == 0)
     {
+        argShowHelp();
         mapERR("No maps specified.\n");
-        goto exit;
+        res = -10;
+        goto out;
     }
 
     if (optNListenTo == 0 && optTest == NULL)
     {
         mapERR("No listeners specified.\n");
-        goto exit;
+        res = -10;
+        goto out;
     }
 
     // Initialize logging
-    if (optLogFilename != NULL && optTest == NULL)
+    if (optLogFilename != NULL && optTest == NULL &&
+        (setLogFH = fopen(optLogFilename, "a")) == NULL)
     {
-        if ((setLogFH = fopen(optLogFilename, "a")) == NULL)
-        {
-            int err = th_get_error();
-            mapERR("Could not open log file '%s' for writing (%d): %s\n",
-                err, th_error_str(err));
-            goto exit;
-        }
+        res = th_get_error();
+        mapERR("Could not open log file '%s' for writing: %s\n",
+            th_error_str(res));
+
+        goto out;
     }
 
     // Load maps
     if (!mapLoadMaps())
-        goto exit;
+    {
+        res = -12;
+        goto out;
+    }
 
     // Check for test mode
     if (optTest != NULL)
@@ -1870,7 +1886,7 @@
             mapERR("Could not read test file.\n");
 
         th_free(buf);
-        goto exit;
+        goto out;
     }
 
     // Initialize libwebsockets and create context
@@ -1881,7 +1897,8 @@
         mapERR("Could not allocate %d bytes of memory for LWS buffer.\n",
             SET_LWS_BUF_SIZE);
 
-        goto exit;
+        res = -13;
+        goto out;
     }
 
     // Setup log handler
@@ -1916,7 +1933,8 @@
     if ((setLWSContext = lws_create_context(&info)) == NULL)
     {
         mapERR("libwebsocket initialization failed.\n");
-        goto exit;
+        res = -14;
+        goto out;
     }
 
     // Create listener LWS vhosts ..
@@ -1977,7 +1995,8 @@
         if ((ctx->vhost = lws_create_vhost(setLWSContext, &info)) == NULL)
         {
             mapERR("LWS vhost creation failed!\n");
-            goto exit;
+            res = -15;
+            goto out;
         }
     }
 
@@ -1993,7 +2012,8 @@
     if (lws_uv_initloop(setLWSContext, NULL, 0))
     {
         mapERR("lws_uv_initloop() failed.\n");
-        goto exit;
+        res = -16;
+        goto out;
     }
 #endif
 
@@ -2001,7 +2021,7 @@
     mapMSG(1, "Waiting for connections...\n");
     lws_service(setLWSContext, 0);
 
-exit:
+out:
     // Shutdown sequence
     mapMSG(1, "Server shutting down.\n");
 
@@ -2027,5 +2047,5 @@
     if (setLogFH)
         fclose(setLogFH);
 
-    return 0;
+    return res;
 }