Report the crash log to mdash

mongoose.c

@@ -7032,11 +7032,31 @@ static void mg_mdash_fn(struct mg_connection *c, int ev, void *ev_data) {
 }
 
 static void mg_mdash_rpc_get_info(struct mg_rpc_req *r) {
-  mg_rpc_ok(r, "{%m:%m,%m:%llu,%m:%m,%m:\"mws.%d\"}", MG_ESC("fw_version"),
+  if (mg_health_valid()) {
-            MG_ESC(MG_MDASH_FIRMWARE_VERSION), MG_ESC("uptime"),
+    uint32_t *data = mg_health_record.backtrace;
-            (uint64_t) (mg_millis() / 1000), MG_ESC("reboot_reason"),
+    mg_rpc_ok(r,
-            MG_ESC(mg_health_reason_str(mg_health_reason())), MG_ESC("arch"),
+              "{%m:%m,%m:%llu,%m:%m,%m:\"mws.%d\",%m:{%m:true,"
-            MG_ARCH);
+              "%m:{%m:\"0x%08lx\",%m:\"0x%08lx\",%m:\"0x%08lx\"},"
+              "%m:{%m:\"0x%08lx\",%m:%m}}}",
+              MG_ESC("fw_version"), MG_ESC(MG_MDASH_FIRMWARE_VERSION),
+              MG_ESC("uptime"), (uint64_t) (mg_millis() / 1000),
+              MG_ESC("reboot_reason"),
+              MG_ESC(mg_health_reason_str(mg_health_reason())), MG_ESC("arch"),
+              MG_ARCH, MG_ESC("report"), MG_ESC("valid"), MG_ESC("regs"),
+              MG_ESC("sp"), (unsigned long) data[0], MG_ESC("lr"),
+              (unsigned long) data[1], MG_ESC("pc"), (unsigned long) data[2],
+              MG_ESC("stack"), MG_ESC("addr"), (unsigned long) data[0],
+              MG_ESC("data"), mg_print_base64,
+              (int) ((MG_HEALTH_BACKTRACE - 3) * sizeof(data[0])),
+              (uint8_t *) &data[3]);
+  } else {
+    mg_rpc_ok(r, "{%m:%m,%m:%llu,%m:%m,%m:\"mws.%d\",%m:{%m:false}}",
+              MG_ESC("fw_version"), MG_ESC(MG_MDASH_FIRMWARE_VERSION),
+              MG_ESC("uptime"), (uint64_t) (mg_millis() / 1000),
+              MG_ESC("reboot_reason"),
+              MG_ESC(mg_health_reason_str(mg_health_reason())), MG_ESC("arch"),
+              MG_ARCH, MG_ESC("report"), MG_ESC("valid"));
+  }
 }
 
 static void mg_mdash_rpc_ota_begin(struct mg_rpc_req *r) {

mongoose.h

@@ -4968,7 +4968,9 @@ enum mg_health_reason {
   MG_HEALTH_RESET_FAULT         // Fault handler ran, see regs[] and saved_stack
 };
 
+#ifndef MG_HEALTH_BACKTRACE
 #define MG_HEALTH_BACKTRACE 20  // Return addresses in mg_health::backtrace
+#endif
 
 struct mg_health {
   char magic[4];          // MG_HEALTH_MAGIC when the record holds valid data

src/health.h

@@ -52,7 +52,9 @@ enum mg_health_reason {
   MG_HEALTH_RESET_FAULT         // Fault handler ran, see regs[] and saved_stack
 };
 
+#ifndef MG_HEALTH_BACKTRACE
 #define MG_HEALTH_BACKTRACE 20  // Return addresses in mg_health::backtrace
+#endif
 
 struct mg_health {
   char magic[4];          // MG_HEALTH_MAGIC when the record holds valid data

src/mdash.c

@@ -91,11 +91,31 @@ static void mg_mdash_fn(struct mg_connection *c, int ev, void *ev_data) {
 }
 
 static void mg_mdash_rpc_get_info(struct mg_rpc_req *r) {
-  mg_rpc_ok(r, "{%m:%m,%m:%llu,%m:%m,%m:\"mws.%d\"}", MG_ESC("fw_version"),
+  if (mg_health_valid()) {
-            MG_ESC(MG_MDASH_FIRMWARE_VERSION), MG_ESC("uptime"),
+    uint32_t *data = mg_health_record.backtrace;
-            (uint64_t) (mg_millis() / 1000), MG_ESC("reboot_reason"),
+    mg_rpc_ok(r,
-            MG_ESC(mg_health_reason_str(mg_health_reason())), MG_ESC("arch"),
+              "{%m:%m,%m:%llu,%m:%m,%m:\"mws.%d\",%m:{%m:true,"
-            MG_ARCH);
+              "%m:{%m:\"0x%08lx\",%m:\"0x%08lx\",%m:\"0x%08lx\"},"
+              "%m:{%m:\"0x%08lx\",%m:%m}}}",
+              MG_ESC("fw_version"), MG_ESC(MG_MDASH_FIRMWARE_VERSION),
+              MG_ESC("uptime"), (uint64_t) (mg_millis() / 1000),
+              MG_ESC("reboot_reason"),
+              MG_ESC(mg_health_reason_str(mg_health_reason())), MG_ESC("arch"),
+              MG_ARCH, MG_ESC("report"), MG_ESC("valid"), MG_ESC("regs"),
+              MG_ESC("sp"), (unsigned long) data[0], MG_ESC("lr"),
+              (unsigned long) data[1], MG_ESC("pc"), (unsigned long) data[2],
+              MG_ESC("stack"), MG_ESC("addr"), (unsigned long) data[0],
+              MG_ESC("data"), mg_print_base64,
+              (int) ((MG_HEALTH_BACKTRACE - 3) * sizeof(data[0])),
+              (uint8_t *) &data[3]);
+  } else {
+    mg_rpc_ok(r, "{%m:%m,%m:%llu,%m:%m,%m:\"mws.%d\",%m:{%m:false}}",
+              MG_ESC("fw_version"), MG_ESC(MG_MDASH_FIRMWARE_VERSION),
+              MG_ESC("uptime"), (uint64_t) (mg_millis() / 1000),
+              MG_ESC("reboot_reason"),
+              MG_ESC(mg_health_reason_str(mg_health_reason())), MG_ESC("arch"),
+              MG_ARCH, MG_ESC("report"), MG_ESC("valid"));
+  }
 }
 
 static void mg_mdash_rpc_ota_begin(struct mg_rpc_req *r) {

tutorials/stm32/nucleo-h723zg/minimal/main.c

@@ -117,27 +117,6 @@ int main(void) {
 
   MG_INFO(("Initialised. CPU clock: %lu MHz", SystemCoreClock / 1000000));
 
-  // Report the previous boot's crash backtrace, if any
-  if (mg_health_reason() == MG_HEALTH_RESET_FAULT) {
-    uint32_t *r = mg_health_record.backtrace;
-    static char buf[512];
-    size_t len = mg_snprintf(
-        buf, sizeof(buf),
-        "{\"image\":\"firmware.elf\",\"binary\":\"firmware.bin\","
-        "\"regs\":{\"sp\":\"0x%08lx\",\"lr\":\"0x%08lx\","
-        "\"pc\":\"0x%08lx\"},\"stack\":{\"addr\":\"0x%08lx\","
-        "\"words\":[",
-        (unsigned long) r[CRASH_SP], (unsigned long) r[CRASH_LR],
-        (unsigned long) r[CRASH_PC], (unsigned long) r[CRASH_SP]);
-    for (size_t i = CRASH_STACK; i < MG_HEALTH_BACKTRACE; i++) {
-      len += mg_snprintf(buf + len, sizeof(buf) - len, "%s\"0x%08lx\"",
-                         i == CRASH_STACK ? "" : ",",
-                         (unsigned long) r[i]);
-    }
-    mg_snprintf(buf + len, sizeof(buf) - len, "]}}");
-    MG_INFO(("Previous boot crash: %s", buf));
-  }
-
   struct mg_mgr mgr;
   mg_mgr_init(&mgr);
   mg_http_listen(&mgr, "http://0.0.0.0", http_ev_handler, NULL);

tutorials/stm32/nucleo-h723zg/minimal/mongoose_config.h

@@ -28,6 +28,7 @@
 
 // Crash report support. Health record lives in the .mg_health region, see link.ld
 #define MG_HEALTH_RAM __attribute__((section(".mg_health")))
+#define MG_HEALTH_BACKTRACE 1022 // fill the 4KB backup SRAM
 
 // mdash.net device management service support
 #define MG_ENABLE_MDASH 1