log: add log query API endpoints and display logs on web interface

main/log_handler.c

@@ -0,0 +1,138 @@
+#include "log_handler.h"
+#include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
+#include <string.h>
+
+static const char *TAG = "LOG_HANDLER";
+
+// Ring buffer for logs
+#define LOG_BUFFER_SIZE 8192
+static char log_buffer[LOG_BUFFER_SIZE];
+static size_t log_write_pos = 0;
+static size_t log_read_pos = 0;
+static size_t log_count = 0;
+static SemaphoreHandle_t log_mutex = NULL;
+static bool log_initialized = false;
+
+// Vprintf callback for capturing logs
+static int log_vprintf_cb(const char *fmt, va_list args) {
+	// First, call the default vprintf to output to console
+	int ret = vprintf(fmt, args);
+
+	// Then, capture to our ring buffer
+	if (log_mutex && log_initialized) {
+		char temp_buf[256];
+		int len = vsnprintf(temp_buf, sizeof(temp_buf), fmt, args);
+		if (len > 0 && len < (int)sizeof(temp_buf)) {
+			xSemaphoreTake(log_mutex, portMAX_DELAY);
+
+			for (int i = 0; i < len; i++) {
+				log_buffer[log_write_pos] = temp_buf[i];
+				log_write_pos = (log_write_pos + 1) % LOG_BUFFER_SIZE;
+
+				if (log_count < LOG_BUFFER_SIZE) {
+					log_count++;
+				} else {
+					// Buffer full, advance read position
+					log_read_pos = (log_read_pos + 1) % LOG_BUFFER_SIZE;
+				}
+			}
+
+			xSemaphoreGive(log_mutex);
+		}
+	}
+
+	return ret;
+}
+
+esp_err_t log_handler_init(void) {
+	if (log_initialized) {
+		ESP_LOGW(TAG, "Log handler already initialized");
+		return ESP_OK;
+	}
+
+	ESP_LOGI(TAG, "Initializing log handler");
+
+	log_mutex = xSemaphoreCreateMutex();
+	if (!log_mutex) {
+		ESP_LOGE(TAG, "Failed to create log mutex");
+		return ESP_ERR_NO_MEM;
+	}
+
+	log_write_pos = 0;
+	log_read_pos = 0;
+	log_count = 0;
+	memset(log_buffer, 0, LOG_BUFFER_SIZE);
+
+	// Set our custom vprintf function
+	esp_log_set_vprintf(log_vprintf_cb);
+
+	log_initialized = true;
+	ESP_LOGI(TAG, "Log handler initialized");
+
+	return ESP_OK;
+}
+
+esp_err_t log_handler_deinit(void) {
+	if (!log_initialized) {
+		return ESP_OK;
+	}
+
+	ESP_LOGI(TAG, "Deinitializing log handler");
+
+	// Restore default vprintf
+	esp_log_set_vprintf(vprintf);
+
+	if (log_mutex) {
+		vSemaphoreDelete(log_mutex);
+		log_mutex = NULL;
+	}
+
+	log_initialized = false;
+	return ESP_OK;
+}
+
+size_t log_get_buffer(char *buf, size_t buf_len) {
+	if (!buf || buf_len == 0 || !log_mutex) {
+		return 0;
+	}
+
+	xSemaphoreTake(log_mutex, portMAX_DELAY);
+
+	size_t to_copy = (log_count < buf_len) ? log_count : buf_len;
+	size_t copied = 0;
+
+	for (size_t i = 0; i < to_copy; i++) {
+		size_t pos = (log_read_pos + i) % LOG_BUFFER_SIZE;
+		buf[copied++] = log_buffer[pos];
+	}
+
+	xSemaphoreGive(log_mutex);
+
+	return copied;
+}
+
+void log_clear_buffer(void) {
+	if (!log_mutex) {
+		return;
+	}
+
+	xSemaphoreTake(log_mutex, portMAX_DELAY);
+	log_write_pos = 0;
+	log_read_pos = 0;
+	log_count = 0;
+	xSemaphoreGive(log_mutex);
+}
+
+size_t log_get_size(void) {
+	if (!log_mutex) {
+		return 0;
+	}
+
+	xSemaphoreTake(log_mutex, portMAX_DELAY);
+	size_t count = log_count;
+	xSemaphoreGive(log_mutex);
+
+	return count;
+}