7.22 version handles FAT FS badly

[Juggler-5]

Hello. Recently I moved to 7.22 from 7.21 and noticed that uploading of files crashed - only less than 1kB or smth are passed, other get reply like: mg_http_reply(c, 400, "", "open(%s)", path); from mg_http_upload(). The only difference I found is old function of file open was like
static void *ff_open(const char *path, int flags) {
FIL f;
unsigned char mode = FA_READ;
if (flags & MG_FS_WRITE) mode |= FA_WRITE | FA_OPEN_ALWAYS | FA_OPEN_APPEND;
if (f_open(&f, path, mode) == 0) {
FIL *fp;
if ((fp = mg_calloc(1, sizeof(*fp))) != NULL) {
memcpy(fp, &f, sizeof(*fp));
return fp;
}
}
return NULL;
}
and new one now is (v7.22)
static void *ff_open(const char *path, int flags) {
FIL *fp = NULL;
unsigned char mode = FA_READ;
if (flags & MG_FS_WRITE) {
mode |= FA_WRITE;
if (flags & MG_FS_EXCL) {
mode |= FA_OPEN_ALWAYS | FA_OPEN_APPEND;
} else {
mode |= FA_CREATE_NEW;
}
}
if ((fp = mg_calloc(1, sizeof(*fp))) != NULL &&
f_open(fp, path, mode) != FR_OK) {
mg_free(fp);
fp = NULL;
}
return fp;
}
Did you test FATFS with this new code? Or maybe you can kindly suggest what should I modify in MG configs to get back to normal?

[scaprile]

I can't have a clue if you don't tell me exactly what you are doing with what, what fails, where, and why.
We know our code, please don't paste it here (even less without formatting), just paste a permalink.
We did change the safe path checker, but we don't run FATFS tests, so if you answer my questions above, I can ask the developer that did those changes or check the path validator (which is in other module and I did)
You should be seeing a debug log or be able to step and see what fails, where, and why.

[Juggler-5]

Rolling back to 21 solves everything. FREERTOS, stm32f429. I tried to follow the rabbit, but you know your code best, thats right. So please advice what could be changed on your side such way, that 22 version allows me to upload files ~1kB (somewhat like buffer size) and fails when file size is larger than ~1kB.

[scaprile]

I already told you, please answer what I asked.
What FATFS version ? Cube ? What is your code ? Is it a minimum HTTP server ? What is the upload path ? Logs ? What do you send ? Which function fails ? Where does it fail ? How ? File transfer starts ? File is truncated ?
Mongoose is not a black box enter request send file, there's your code there, we need all the information.
You are using FreeRTOS, are all calls to Mongoose from within one and the very same thread ?

[Juggler-5]

What FATFS version ? FatFs - Generic FAT Filesystem module R0.16 #define FF_DEFINED 80386- latest from their repo I suppose.
Cube ? Version: 2.1.1
What is your code ?
Is it a minimum HTTP server ?
It is I suppose, all from your examples. Use additionally USB stack from ST, FATFS is for external flash memory where I can upload anything I need.
All calls to Mongoose from within one and the very same thread, yes.
What is the upload path ? Logs ? What do you send ? Which function fails ? Where does it fail ? How ? File transfer starts ? File is truncated ?
Well if I try to upload via mg_http_upload(c, hm, &mg_fs_fat, "0:", UPL_FILE_SZ_MAX); I cant upload file with 3kB anymore, that`s what MG says: open(0:/new upl.txt). If I cut this file to <1kB, MG says the size of this file - 356 for example.
Again, all my code works on 21 version, without any known limits for file size uploading.
Could it be caused by mallocs or smth? Maybe v22 is more hungry for RAM?

[scaprile]

@cpq My capacity for understanding has been exceeded. Looks like the open call to FATFS is failing for sizes > 1K or 3K with the latest flags. Perhaps there is some fragmentation somewhere and some flags cause the call to fail ? I can't guess anything else.
The OP seems to be building with Cube some code of his based on some example of ours, running on some version of FreeRTOS on some board with an F429, using some Cube USB library to access some media. It doesn't seem to be the HTTP code nor the path sanitizer, IIUC it is the open call that fails, I seem to understand.

[Juggler-5]

Hello. Finally I`ve found the problem, it was in mg_http_upload() - if I change flags to file open function like this : mg_fs_open(fs, path, (MG_FS_WRITE | MG_FS_EXCL))) it works as before. Now in ver7.23 you still have it like mg_fs_open(fs, path, MG_FS_WRITE)) and that fails on FATFS. In other words, flags for proper file open using FATFS should be FA_WRITE | FA_OPEN_ALWAYS | FA_OPEN_APPEND. Hope you can patch this easily.

[scaprile]

Please test code in https://github.com/cesanta/mongoose/tree/fatfs
PR #3665

[Juggler-5]

Thats how we like it 👍 Thank you, problems vanished.