WIP WIP WIP : Adding notice in README.md

Signed-off-by: Ludovic LANGE <[email protected]>

README.md

@@ -1,3 +1,59 @@
+> **Warning**  
+> This branch is a Work-In-Progress to add compatibility with ESP-IDF v4.x and v5.x.  
+> Not suitable for production use - only for dev / tests.  
+> As of now, it (kind-of) works on ESP-IDF v5.0 with the following caveats:
+> * the crash handler (`xt_set_error_handler_callback` and `esp_task_wdt_get_trigger_tasknames`) is disabled for the moment, we need to decide whether we "fork" ESP-IDF again to port it ; or if the new APIs are enough to (partially ?) reimplement it (see commit: "**WIP WIP WIP : comment out ESP-IDF specifics of our fork**")
+> * There is a crash in `OvmsConsole::Poll` which is not analysed (yet) and which is worked around by declaring a variable static (see commit: "**WIP WIP WIP : prevent a crash at boot (to be analysed)**")
+> * Our (previously) local copies of `wolfssh` and `wolfssl` are now in submodules (and moved one level below in terms of directories) - mainly to be able to have a CMakeLists.txt different from the upstream one. In the process, one of our previous patches is now lost : https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/commit/51444539047daef7bd2accb23ef40d1bc14fdb20 and we need to decide how to handle this.
+> * A lot of dependencies are now explicitly (hard-)coded in the CMakeLists.txt - which may, or may not be a good thing. Let's discuss it.
+> * The set of defines (in ovms_webserver) have been transformed into a header generation because it was not known how to implement those in a satisfying manner in cmake.
+> * There are still some warnings during compilation (mainly ADC which needs conversion + some others)
+> * Mongoose is not (yet) ready to compile with TLS enabled.
+> * wolfSSL can't be (yet) compiled with OPENSSL defines (see wolfSSL/wolfssl#6028)
+> * wolfSSL has been updated to tag `v5.3.0-stable` (Note: later versions causing stack overflow during SSH session, to investigate)
+> * wolfSSH has been updated to tag `v1.4.6-stable`
+> * mongoose has not been updated but needs patching (see below for the patch)
+> * Some commits (identified by "WIP WIP WIP") needs to be addressed
+> * No real-world test has been done
+> * We wanted to stay compatible with our 3.3.4 branch, and tried as much as we could to keep that compatibility. In case something is broken, please report and we will fix it.
+> * This branch has mainly been tested using `cmake` build system / `idf.py`, not Makefiles (which have disappeared in v5.x)
+
+### Patch for mongoose
+```patch
+diff --git a/mongoose.c b/mongoose.c
+index b12cff18..60a7f62e 100644
+--- a/mongoose.c
++++ b/mongoose.c
+@@ -9160,7 +9160,7 @@ static void mg_send_file_data(struct mg_connection *nc, FILE *fp) {
+ static void mg_do_ssi_include(struct mg_connection *nc, struct http_message *hm,
+                               const char *ssi, char *tag, int include_level,
+                               const struct mg_serve_http_opts *opts) {
+-  char file_name[MG_MAX_PATH], path[MG_MAX_PATH], *p;
++  char file_name[MG_MAX_PATH], path[MG_MAX_PATH+2], *p;
+   FILE *fp;
+
+   /*
+diff --git a/mongoose.h b/mongoose.h
+index 3bcf8147..5649e1a7 100644
+--- a/mongoose.h
++++ b/mongoose.h
+@@ -1768,7 +1768,7 @@ typedef struct {
+
+ void cs_md5_init(cs_md5_ctx *c);
+ void cs_md5_update(cs_md5_ctx *c, const unsigned char *data, size_t len);
+-void cs_md5_final(unsigned char *md, cs_md5_ctx *c);
++void cs_md5_final(unsigned char md[16], cs_md5_ctx *c);
+
+ #ifdef __cplusplus
+ }
+```
+
+Instructions for ESP-IDF v5.0:
+* Setup ESP-IDF where you want and ensure it works, [following the instructions here](https://docs.espressif.com/projects/esp-idf/en/v5.0/esp32/get-started/index.html).
+* Build as usual (`idf.py build`, etc...)
+
+---
+
 # Open-Vehicle-Monitoring-System-3 (OVMS3)
 
 ![OVMS3 module](docs/source/userguide/ovms-intro.jpg)