sdl-audio/log.c

#include "log.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <time.h>

const char* get_current_time()
{
	static char buffer[20];
	time_t now = time(NULL);
	struct tm* tm_info = localtime(&now);
	strftime(buffer, sizeof(buffer), "%Y-%m-%d %H:%M:%S", tm_info);
	return buffer;
}

void log_message(LogLevel level, const char* format, ...)
{
	const char* level_strings[] = { "INFO", "WARNING", "ERROR" };
	static char* last_message = NULL;
	static unsigned int repeat_count = 0;
	static unsigned int exp_count = 1;
	char* message = NULL;

	// Open the log file in append mode
	FILE* log_file = fopen("logfile.txt", "a");
	if (log_file == NULL) {
		fprintf(stderr, "Could not open log file for writing.\n");
		return;
	}

	va_list args;

	va_start(args, format);
	int message_size =  vsnprintf(NULL, 0, format, args) + 1;
	va_end(args);

	va_start(args, format);
	message = malloc(message_size);
	vsnprintf(message, message_size, format, args);
	va_end(args);

	if (!last_message) goto output;
	// If current and last messages different
	if (strcmp(message, last_message)) {
		repeat_count = 0;
		exp_count = 1;
		goto output;
	}
	repeat_count++;
	if (repeat_count < LOG_MAX_REPEAT) goto output;

	unsigned int bit_width = sizeof(exp_count) * 8; // Calculate the number of bits in an int
	unsigned int leftmost_bit_mask = 1 << (bit_width - 1); // Create a mask with the
	while (exp_count < repeat_count && exp_count < leftmost_bit_mask) exp_count = exp_count << 1;
	if (repeat_count != exp_count && repeat_count != LOG_MAX_REPEAT) goto clean;

	fprintf(log_file, "[%s] [%s] %s !! x%u !!\n", get_current_time(), level_strings[level], last_message, repeat_count);
	printf("[%s] %s !! x%u !!\n", level_strings[level], last_message, repeat_count);

	goto clean;
output:
	// Write the log message to the file
	fprintf(log_file, "[%s] [%s] ", get_current_time(), level_strings[level]);
	fprintf(log_file, "%s", message);
	fprintf(log_file, "\n");
	// Write to stdout
	printf("[%s] ", level_strings[level]);
	printf("%s", message);
	printf("\n");
	// Record last message
	if (last_message) free(last_message);
	last_message = malloc(message_size);
	strcpy(last_message, message);
clean:
	free(message);
	fclose(log_file);
}