Add modbus dashboard

examples/modbus-dashboard/Makefile

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+PROG ?= ./example       # Program we are building
+PACK ?= ./pack          # Packing executable
+DELETE = rm -rf         # Command to remove files
+GZIP ?= gzip            # For compressing files in web_root/
+OUT ?= -o $(PROG)       # Compiler argument for output file
+SOURCES = main.c mongoose.c net.c packed_fs.c   # Source code files
+CFLAGS = -W -Wall -Wextra -g -I.                # Build options
+
+# Mongoose build options. See https://mongoose.ws/documentation/#build-options
+CFLAGS_MONGOOSE += -DMG_ENABLE_PACKED_FS=1
+
+ifeq ($(OS),Windows_NT)         # Windows settings. Assume MinGW compiler. To use VC: make CC=cl CFLAGS=/MD OUT=/Feprog.exe
+  PROG = example.exe            # Use .exe suffix for the binary
+  PACK = pack.exe               # Packing executable
+  CC = gcc                      # Use MinGW gcc compiler
+  CFLAGS += -lws2_32            # Link against Winsock library
+  DELETE = cmd /C del /Q /F /S  # Command prompt command to delete files
+  GZIP = echo                   # No gzip on Windows
+endif
+
+# Default target. Build and run program
+all: $(PROG)
+	$(RUN) $(PROG) $(ARGS)
+
+# Build program from sources
+$(PROG): $(SOURCES)
+	$(CC) $(SOURCES) $(CFLAGS) $(CFLAGS_MONGOOSE) $(CFLAGS_EXTRA) $(OUT)
+
+# Bundle JS libraries (preact, preact-router, ...) into a single file
+web_root/bundle.js:
+	curl -s https://npm.reversehttp.com/preact,preact/hooks,htm/preact,preact-router -o $@
+
+# Create optimised CSS. Prerequisite: npm -g i tailwindcss tailwindcss-font-inter
+web_root/main.css: web_root/index.html $(wildcard web_root/*.js)
+	npx tailwindcss -o $@ --minify
+
+# Generate packed filesystem for serving Web UI
+packed_fs.c: $(wildcard web_root/*) $(wildcard certs/*) Makefile web_root/main.css web_root/bundle.js
+	$(GZIP) web_root/*
+	$(CC) ../../test/pack.c -o $(PACK)
+	$(PACK) web_root/* certs/* > $@
+	$(GZIP) -d web_root/*
+
+mbedtls:
+	git clone --depth 1 -b v2.28.2 https://github.com/mbed-tls/mbedtls $@
+
+ifeq ($(TLS), mbedtls)
+CFLAGS += -DMG_TLS=MG_TLS_MBED -Wno-conversion -Imbedtls/include
+CFLAGS += -DMBEDTLS_CONFIG_FILE=\"mbedtls_config.h\" mbedtls/library/*.c
+$(PROG): mbedtls
+endif
+
+# Cleanup. Delete built program and all build artifacts
+clean:
+	$(DELETE) $(PROG) $(PACK) *.o *.obj *.exe *.dSYM mbedtls

examples/modbus-dashboard/README.md

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+# A complete device dashboard
+
+This example is a demonstration of how Mongoose Library could be integrated
+into an embedded device and provide a complete device dashboard with the
+following features:
+
+- Authentication: login-protected dashboard
+- Multiple logins (with possibly different permissions)
+- The Web UI can be fully embedded into the firmware binary, then not
+  needing a filesystem to serve it; so being resilient to FS problems
+- All changes are propagated to all connected clients
+
+## Screenshots
+
+This is a login screen that prompts for user/password
+
+![](screenshots/login.webp)
+
+## Main dashboard
+
+The main dashboard page shows the interactive console
+
+![](screenshots/dashboard.webp)
+
+
+See a detailed tutorial at https://mongoose.ws/tutorials/device-dashboard/

examples/modbus-dashboard/certs

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+../device-dashboard/certs

examples/modbus-dashboard/main.c

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+// Copyright (c) 2020-2023 Cesanta Software Limited
+// All rights reserved
+
+#include "mongoose.h"
+#include "net.h"
+
+static int s_sig_num;
+static void signal_handler(int sig_num) {
+  signal(sig_num, signal_handler);
+  s_sig_num = sig_num;
+}
+
+int main(void) {
+  struct mg_mgr mgr;
+
+  signal(SIGPIPE, SIG_IGN);
+  signal(SIGINT, signal_handler);
+  signal(SIGTERM, signal_handler);
+
+  mg_log_set(MG_LL_DEBUG);  // Set debug log level
+  mg_mgr_init(&mgr);
+
+  web_init(&mgr);
+  while (s_sig_num == 0) {
+    mg_mgr_poll(&mgr, 50);
+  }
+
+  mg_mgr_free(&mgr);
+  MG_INFO(("Exiting on signal %d", s_sig_num));
+
+  return 0;
+}

examples/modbus-dashboard/mongoose.c

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+../../mongoose.c

examples/modbus-dashboard/mongoose.h

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+../../mongoose.h