ESP LOG redirect to own function bug.

[zekageri]

If i set the esp_log_set_vprintf(redirectToF_System); than my function is never called when ESP crashes.

static char log_print_buffer[512];
static char APP_NAME[] = "My_Home";
static char Crash_File_Path[] = "/Crash_LOGS.txt";

int redirectToF_System(const char *szFormat, va_list args) {
    int ret = vsnprintf(log_print_buffer, sizeof(log_print_buffer), szFormat, args);
    if (ret >= 0){
        File g;
        if(LITTLEFS.exists(Crash_File_Path)){
            g = LITTLEFS.open(Crash_File_Path, "a");
        }else{
            g = LITTLEFS.open(Crash_File_Path, "w");
        }
        if (!g) {}else{
            g.write((uint8_t *)log_print_buffer, (size_t)ret);
        }
        g.close();
    }
    return ret;
}
static const inline void Crash_Log_Init(){
    esp_log_set_vprintf(redirectToF_System);
    esp_log_level_set("*", ESP_LOG_VERBOSE);
    //LITTLEFS.remove(Crash_File_Path);
    ESP_LOGI(APP_NAME, "Writing via ESP_LOGI!\n");
    esp_log_write(ESP_LOG_VERBOSE, APP_NAME, "I can write like this all day.\n"); // THIS LINE IS WORKING PROPERLY!
}
void setup(){
Serial.begin(115200);
Crash_Log_Init();
}

[lbernstone]

Two issues:

1. esp_log_level_set("*", ESP_LOG_VERBOSE); does not change the logging level. Use ESP_LOGE in your testing. AFAIK you will need to rebuild the libraries to change the IDF logging level.
2. esp32-hal-log.h redefines all the log functions such that vprintf is not used. If you modify the file as follows, you can redirect to file.

#ifndef __ARDUHAL_LOG_H__
#define __ARDUHAL_LOG_H__

#ifdef __cplusplus
extern "C"
{
#endif

#include "sdkconfig.h"
#include "esp_timer.h"

#define ARDUHAL_LOG_LEVEL_NONE       (0)
#define ARDUHAL_LOG_LEVEL_ERROR      (1)
#define ARDUHAL_LOG_LEVEL_WARN       (2)
#define ARDUHAL_LOG_LEVEL_INFO       (3)
#define ARDUHAL_LOG_LEVEL_DEBUG      (4)
#define ARDUHAL_LOG_LEVEL_VERBOSE    (5)

const char * pathToFileName(const char * path);
int log_printf(const char *fmt, ...);

#define log_v(format, ...)
#define isr_log_v(format, ...)

#define log_d(format, ...)
#define isr_log_d(format, ...)

#define log_i(format, ...)
#define isr_log_i(format, ...)

#define log_w(format, ...)
#define isr_log_w(format, ...)

#define log_e(format, ...)
#define isr_log_e(format, ...)

#define log_n(format, ...)
#define isr_log_n(format, ...)

#include "esp_log.h"

#ifdef __cplusplus
}
#endif

#endif /* __ESP_LOGGING_H__ */

[zekageri]

Two issues:

1. esp_log_level_set("*", ESP_LOG_VERBOSE); does not change the logging level. Use ESP_LOGE in your testing. AFAIK you will need to rebuild the libraries to change the IDF logging level.
2. esp32-hal-log.h redefines all the log functions such that vprintf is not used. If you modify the file as follows, you can redirect to file.

#ifndef __ARDUHAL_LOG_H__
#define __ARDUHAL_LOG_H__

#ifdef __cplusplus
extern "C"
{
#endif

#include "sdkconfig.h"
#include "esp_timer.h"

#define ARDUHAL_LOG_LEVEL_NONE       (0)
#define ARDUHAL_LOG_LEVEL_ERROR      (1)
#define ARDUHAL_LOG_LEVEL_WARN       (2)
#define ARDUHAL_LOG_LEVEL_INFO       (3)
#define ARDUHAL_LOG_LEVEL_DEBUG      (4)
#define ARDUHAL_LOG_LEVEL_VERBOSE    (5)

const char * pathToFileName(const char * path);
int log_printf(const char *fmt, ...);

#define log_v(format, ...)
#define isr_log_v(format, ...)

#define log_d(format, ...)
#define isr_log_d(format, ...)

#define log_i(format, ...)
#define isr_log_i(format, ...)

#define log_w(format, ...)
#define isr_log_w(format, ...)

#define log_e(format, ...)
#define isr_log_e(format, ...)

#define log_n(format, ...)
#define isr_log_n(format, ...)

#include "esp_log.h"

#ifdef __cplusplus
}
#endif

#endif /* __ESP_LOGGING_H__ */

Thank you for your support. I will try it with your suggestions and report back!

[zekageri]

I don't really understand what should i modify.

In the esp32-hal-log.h there is one reference to const char * pathToFileName(const char * path); and it is used in one definition:

#define ARDUHAL_LOG_FORMAT(letter, format) ARDUHAL_LOG_COLOR_ ## letter "[" #letter "][%s:%u] %s(): " format ARDUHAL_LOG_RESET_COLOR "\r\n", pathToFileName(__FILE__), __LINE__, __FUNCTION__

When i do:

static const inline void Crash_Log_Init(){
    esp_log_set_vprintf(redirectToF_System);
    ESP_LOGE(APP_NAME, "Writing via ESP_LOGI!\n");
    esp_log_write(ESP_LOG_ERROR, APP_NAME, "I can write like this all day.\n");
}

I get some loggings to my file:

I can write like this all day.
I can write like this all day.
I can write like this all day.
E (1710913) esp_littlefs: Failed to unlink path "/Home_index.html". Has open FD.
E (2672737) esp_littlefs: Failed to unlink path "/Home_index.html". Has open FD.
E (3012752) esp_littlefs: Failed to unlink path "/Home_index.html". Has open FD.
E (4303186) esp_littlefs: Failed to unlink path "/Home_index.html". Has open FD.
I can write like this all day.
I can write like this all day.
I can write like this all day.
I can write like this all day.
I can write like this all day.
I can write like this all day.

If i try this way:

`ARDUHAL_LOG_FORMAT(APP_NAME,Crash_File_Path);`

I get a compile error:

.platformio/packages/framework-arduinoespressif32/cores/esp32/esp32-hal-log.h:78:45: error: 'ARDUHAL_LOG_COLOR_APP_NAME' was not declared in this scope

[lbernstone]

What I have showed you is how to rip out the arduino logging, so there is no ARDUHAL_LOG_FORMAT. You will now need to fill those empty defines with the format that you want, and have them use your new function.

[martirius]

Hi. I have opened a PR related to this issue:
#4845

[tbertels]

Hi. I have opened a PR related to this issue: #4845

With this PR and adding -DUSE_ESP_IDF_LOG to build.extra_flags platform.txt and removing the #define ESP_LOG lines in esp32-hal-log.h (per https://stackoverflow.com/questions/60442350/arduinos-esp-log-set-vprintf-does-not-work-on-esp32 question comments), I can get some logging messages written to SPIFFS. Log messages related to Wifi and such.

But I still can't get crash logs written to SPIFFS. They're still getting sent to UART.

Did anybody manage to make it work?

[martirius]

Hi @tbertels , I don't think that is possible to do, because wiritng on the SPIFFS it's an heavy work and something you can't do in an interrupt.

[zekageri]

Hi @tbertels , I don't think that is possible to do, because wiritng on the SPIFFS it's an heavy work and something you can't do in an interrupt.

Why can't we add to queue and write in another task?

[zekageri]

I'm still trying. Nothing seems to work

Hi @martirius @tbertels,

I am facing an implementation issue regarding the use of the above PR. When I use log_x() by defining USE_ESP_IDF_LOG and DCORE_DEBUG_LEVEL=ARDUHAL_LOG_LEVEL_VERBOSE I only get the logs printed on serial monitor for log_e() and not for any other levels i.e., log_d(), log_w(), log_i(), etc.

However, when I only define DCORE_DEBUG_LEVEL=ARDUHAL_LOG_LEVEL_VERBOSE, I get the logs printed for each level.

Sketch:

#include <Arduino.h>

void setup()
{
    Serial.begin(115200);
    Serial.println("Configuring the SPIFFS of ESP32...");
    log_e("[Error] Hey there");
    log_w("[Warn] Hey There");
    log_i("[Info] Hey There");
    log_d("[Debug] Hey There");
    log_v("[Verbose] Hey there");
}

void loop()
{
}

Output: [With DCORE_DEBUG_LEVEL=ARDUHAL_LOG_LEVEL_VERBOSE]

Configuring the SPIFFS of ESP32...
[E][ESP32_Logging_SPIFFS_WebServer.cpp:18] setup(): [Error] Hey there
[W][ESP32_Logging_SPIFFS_WebServer.cpp:19] setup(): [Warn] Hey There
[I][ESP32_Logging_SPIFFS_WebServer.cpp:20] setup(): [Info] Hey There
[D][ESP32_Logging_SPIFFS_WebServer.cpp:21] setup(): [Debug] Hey There
[V][ESP32_Logging_SPIFFS_WebServer.cpp:22] setup(): [Verbose] Hey there

Output: [With DCORE_DEBUG_LEVEL=ARDUHAL_LOG_LEVEL_VERBOSE and USE_ESP_IDF_LOG]

Configuring the SPIFFS of ESP32...
E (28) ARDUINO: [Error] Hey there

Can you please guide me in the right direction as to why this might be happening? Do I need to set some logging define or anything else? Thanks.