LFS nits

tutorials/device-dashboard/full/dashboard.c

@@ -150,7 +150,7 @@ static bool graph1_fn(enum mg_dash_op op, struct mg_dash_user *u) {
   return true;
 }
 static struct mg_field_set set_graph1 = {"graph1", fields_graph1, graph1_fn,
-                                         NULL,     NULL};
+                                         NULL, NULL};
 
 #define NUM_POINTS_GRAPH2 100  // How many graph2 data points to send
 static char s_graph2_data[NUM_POINTS_GRAPH2 * 4 + 2 + 1];
@@ -218,6 +218,7 @@ void mg_dash_init(struct mg_mgr *mgr) {
 
 #if MG_ARCH == MG_ARCH_UNIX
   // Create demo files in the upload directory
+  mkdir("/tmp", 0755);
   mkdir("/tmp/dashboard", 0755);
   mg_file_printf(&mg_fs_posix, "/tmp/dashboard/device-config.json",
                  "{\"model\":\"example\",\"fw\":\"1.0\"}");

tutorials/device-dashboard/full/dashboard.html

@@ -778,15 +778,22 @@ a, a:visited, a:link { text-decoration: none; }
           </div>
 
           <div class="note">
-            <p>The two default files are fake - you can delete them</p>
-            <p>However the manager works - you can upload new files. They
-              are uploaded to /tmp/ directory on the device.
-              This requires stdio (fopen/fread/...) implemeneted.</p>
-            <p>The easiest way to implement it is to use a filesystem like
-              LittleFS on your internal or external flash
-              and retarget the standard library to use it.</p>
-            <p>See <a href="https://github.com/cpq/bare-metal-programming-guide/tree/main/templates/lfs/nucleo-h563zi">this example</a> on how LittleFS can be implemented on
-              Nucleo-H563ZI internal flash partition.</p>
+            <p>This file manager uses /tmp/dashboard/ directory.
+              It works on any platform that supports
+              standard file IO: fopen, fread, fwrite, fclose.
+              This includes Linux/Mac/Windows.</p>
+            <p>
+              Mongoose provides a built-in LittleFS integration that
+              makes stadard file IO work on embedded systems like STM32.
+              For that, add "#define MG_ENABLE_LFS 1" to your
+              mongoose_config.h
+            </p>
+            <p>See
+              <a href="https://github.com/cesanta/embedded-web-file-manager">this ready-to-build example</a>
+              which implements LittleFS on Nucleo-H563ZI internal flash. You
+              can upload, delete and serve files on STM32 - which is
+              a perfect use case for confuration files, keeping and viewing logs, etc.
+            </p>
           </div>
 
         </div>

tutorials/stm32/nucleo-h563zi/minimal/Makefile

@@ -1,23 +1,26 @@
 # Copyright (c) 2026 Cesanta Software Limited
 # Environment setup: https://mongoose.ws/docs/getting-started/build-environment/
 
+MGDIR = ../../../..
+
 CFLAGS  = -W -Wall -Wextra -Wundef -Wshadow -Wdouble-promotion
 CFLAGS += -Wformat-truncation -fno-common -Wconversion -Wno-sign-conversion
 CFLAGS += -g3 -Os -ffunction-sections -fdata-sections
-CFLAGS += -I. -Icmsis_core/CMSIS/Core/Include -Icmsis_h5/Include -Imongoose
+CFLAGS += -I. -I$(MGDIR) -Icmsis_core/CMSIS/Core/Include -Icmsis_h5/Include -Imongoose
 CFLAGS += -mcpu=cortex-m33 -mthumb -mfpu=fpv5-sp-d16 -mfloat-abi=hard $(CFLAGS_EXTRA)
 LDFLAGS ?= -Tlink.ld -nostdlib -nostartfiles --specs nosys.specs -lc -lgcc -Wl,--gc-sections -Wl,-Map=$@.map
 
 SOURCES = main.c hal.c
+SOURCES += littlefs/lfs.c littlefs/lfs_util.c
 SOURCES += cmsis_h5/Source/Templates/gcc/startup_stm32h563xx.s
-SOURCES += mongoose/mongoose.c
+SOURCES += $(MGDIR)/mongoose.c
+
+# Disabled for littlefs/lfs.c
+CFLAGS += -Wno-conversion -Wno-shadow
 
 all build example: firmware.bin
 
-mongoose/mongoose.c mongoose/mongoose.h:
-	cp ../../../../mongoose.[ch] mongoose/
-
-firmware.elf: cmsis_core cmsis_h5 hal.h link.ld Makefile $(SOURCES) mongoose/mongoose.h
+firmware.elf: cmsis_core cmsis_h5 littlefs hal.h link.ld Makefile $(SOURCES) $(MGDIR)/mongoose.h
 	arm-none-eabi-gcc $(SOURCES) $(CFLAGS) $(CFLAGS_EXTRA) $(LDFLAGS) -o $@
 
 firmware.bin: firmware.elf
@@ -42,6 +45,10 @@ cmsis_core:
 cmsis_h5:
 	git clone -q -c advice.detachedHead=false --depth 1 -b v1.6.0 https://github.com/STMicroelectronics/cmsis-device-h5 $@
 
+littlefs/lfs.c littlefs/lfs_util.c: littlefs
+littlefs:
+	git clone -q -c advice.detachedHead=false --depth 1 -b v2.11.3 https://github.com/littlefs-project/littlefs $@
+
 clean:
 	rm -rf firmware.* cmsis_* mongoose/mongoose.*
 

tutorials/stm32/nucleo-h563zi/minimal/main.c

@@ -45,8 +45,20 @@ static void http_ev_handler(struct mg_connection *c, int ev, void *ev_data) {
     struct mg_http_message *hm = (struct mg_http_message *) ev_data;
     if (mg_match(hm->uri, mg_str("/api/tick"), NULL)) {
       mg_http_reply(c, 200, "", "{%m:%llu}\n", MG_ESC("tick"), hal_get_tick());
+    } else if (mg_match(hm->uri, mg_str("/files/#"), NULL)) {
+      struct mg_http_serve_opts opts = {
+          .root_dir = "/files/=/fs/",
+          .allow_delete = true,
+          .allow_upload = true,
+      };
+      mg_http_serve_dir(c, hm, &opts);
     } else {
-      mg_http_reply(c, 200, "", "Hi from Mongoose, tick %llu\n", hal_get_tick());
+      size_t u = hal_ram_used(), t = u + hal_ram_free();
+      mg_http_reply(c, 200, "",
+                    "Hi from Mongoose!\n"
+                    "Tick %llu\n"
+                    "RAM usage: %zu / %zu (%zu %%)\n",
+                    hal_get_tick(), u, t, (size_t) (100 * u / t));
     }
   }
 }
@@ -67,6 +79,14 @@ int main(void) {
   mg_mgr_init(&mgr);
   mg_http_listen(&mgr, "http://0.0.0.0", http_ev_handler, NULL);
 
+  // Create directory for Web file manager. Will be mapped to /files/ URL
+  mkdir("/fs", 0755);
+  MG_INFO(("File manager operations:"));
+  MG_INFO(("Upload: curl IP/files/NAME --data-binary @FILE"));
+  MG_INFO(("Delete: curl IP/files/NAME -X DELETE"));
+  MG_INFO(("Show:   curl IP/files/NAME"));
+  MG_INFO(("List:   curl IP/files/"));
+
   for (;;) {
     mg_mgr_poll(&mgr, 0);
     blink_task();

tutorials/stm32/nucleo-h563zi/minimal/mongoose_config.h

@@ -12,6 +12,11 @@
 #define MG_ENABLE_PACKED_FS 1
 #define MG_ENABLE_DRIVER_STM32H 1
 
+#define MG_ENABLE_LFS 1  // Enable POSIX filesystem on interfal flash using LFS
+#define MG_LFS_SIZE (1024 * 128)  // Must be multiple of H5 8Kb sectors
+#define MG_OTA MG_OTA_STM32H5     // MG_OTA required for LFS, for flash usage
+#define MG_ENABLE_LINES 1
+
 // #define MG_DRIVER_MDC_CR 4   // RMII MDC clock divider, from 0 to 4
 // #define MG_TCPIP_PHY_ADDR 0  // PHY address