From 5aba8a2fa639bc65dd5ad786f8a725f5276c18e7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franti=C5=A1ek=20Boh=C3=A1=C4=8Dek?=
 <fandabohacek@gmail.com>
Date: Mon, 14 Jun 2021 21:37:25 +0200
Subject: [PATCH] feat: add logger

---
 image-viewer/include/logger.h |  44 ++++++++++++++
 image-viewer/src/logger.c     | 105 ++++++++++++++++++++++++++++++++++
 2 files changed, 149 insertions(+)
 create mode 100644 image-viewer/include/logger.h
 create mode 100644 image-viewer/src/logger.c

diff --git a/image-viewer/include/logger.h b/image-viewer/include/logger.h
new file mode 100644
index 0000000..5ddb30d
--- /dev/null
+++ b/image-viewer/include/logger.h
@@ -0,0 +1,44 @@
+#ifndef _LOGGER_H
+#define _LOGGER_H
+
+#include <stdio.h>
+
+#define DEBUG_PREFIX "[DEBG]"
+#define INFO_PREFIX  "[INFO]"
+#define WARN_PREFIX  "[WARN]"
+#define ERROR_PREFIX "[ERRO]"
+
+typedef enum LogLevel {
+  LOG_DEBUG = 1,
+  LOG_INFO = 2,
+  LOG_WARN = 3,
+  LOG_ERROR = 4,
+} LogLevel;
+
+typedef struct logger_t logger_t;
+
+struct logger_t {
+  FILE *debugFile;
+  FILE *infoFile;
+  FILE *warningFile;
+  FILE *errorFile;
+
+  LogLevel minimalLevel;
+
+  logger_t *childLogger; // Duplicate logs to this logger
+};
+
+logger_t logger_create(LogLevel minimalLevel, FILE *debugFile, FILE *infoFile, FILE *warningFile,
+                     FILE *errorFile, logger_t *childLogger);
+
+void logger_log(logger_t *logger, LogLevel level, const char *file, const char *function, int line, const char *const message, ...);
+void logger_debug(logger_t *logger, const char *file, const char *function,
+                  int line, const char *const message, ...);
+void logger_info(logger_t *logger, const char *file, const char *function,
+                 int line, const char *const message, ...);
+void logger_warn(logger_t *logger, const char *file, const char *function,
+                 int line, const char *const message, ...);
+void logger_error(logger_t *logger, const char *file, const char *function,
+                  int line, const char *const message, ...);
+
+#endif //_LOGGER_H
diff --git a/image-viewer/src/logger.c b/image-viewer/src/logger.c
new file mode 100644
index 0000000..b7b3fba
--- /dev/null
+++ b/image-viewer/src/logger.c
@@ -0,0 +1,105 @@
+#include "logger.h"
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <time.h>
+
+logger_t logger_create(LogLevel minimalLevel, FILE *debugFile, FILE *infoFile, FILE *warningFile,
+                     FILE *errorFile, logger_t *childLogger) {
+  logger_t logger = { debugFile, infoFile, warningFile, errorFile, minimalLevel, childLogger };
+  return logger;
+}
+
+void print_time(FILE *file) {
+  time_t now;
+  time(&now);
+  struct tm *local = localtime(&now);
+
+  fprintf(file, "%02d:%02d:%02d", local->tm_hour, local->tm_min, local->tm_sec);
+}
+
+void logger_log_vaargs(logger_t *logger, LogLevel level, const char *file_name,
+                       const char *function, int line,
+                       const char *const message, va_list args) {
+  if (logger->childLogger != NULL) {
+    va_list copy;
+    va_copy(copy, args);
+    logger_log_vaargs(logger->childLogger, level, file_name, function, line, message, copy);
+    va_end(copy);
+  }
+
+  if (level < logger->minimalLevel) {
+    return;
+  }
+
+  FILE *file = NULL;
+  const char *prefix;
+
+  switch (level) {
+  case LOG_DEBUG:
+    file = logger->debugFile;
+    prefix = DEBUG_PREFIX;
+    break;
+  case LOG_INFO:
+    file = logger->infoFile;
+    prefix = INFO_PREFIX;
+    break;
+  case LOG_WARN:
+    file = logger->warningFile;
+    prefix = WARN_PREFIX;
+    break;
+  case LOG_ERROR:
+    file = logger->errorFile;
+    prefix = ERROR_PREFIX;
+    break;
+  }
+
+  assert(file != NULL);
+  fprintf(file, "[");
+  print_time(file);
+  fprintf(file, "] %s: ", prefix);
+  vfprintf(file, message, args);
+  fprintf(file, "(%s/%s:%s)", file_name, function, line);
+  fprintf(file, "\r\n");
+}
+
+void logger_log(logger_t *logger, LogLevel level, const char *file,
+                const char *function, int line,
+                const char *const message, ...) {
+  va_list args;
+  va_start(args, message);
+  logger_log_vaargs(logger, level, file, function, line, message, args);
+  va_end(args);
+}
+
+void logger_debug(logger_t *logger, const char *file, const char *function,
+                  int line, const char *const message, ...) {
+  va_list args;
+  va_start(args, message);
+  logger_log_vaargs(logger, LOG_DEBUG, file, function, line, message, args);
+  va_end(args);
+}
+
+void logger_info(logger_t *logger, const char *file, const char *function,
+                 int line, const char *const message, ...) {
+  va_list args;
+  va_start(args, message);
+  logger_log_vaargs(logger, LOG_INFO, file, function, line, message, args);
+  va_end(args);
+}
+void logger_warn(logger_t *logger, const char *file, const char *function,
+                 int line, const char *const message, ...) {
+  va_list args;
+  va_start(args, message);
+  logger_log_vaargs(logger, LOG_WARN, file, function, line, message, args);
+  va_end(args);
+}
+
+void logger_error(logger_t *logger, const char *file, const char *function,
+                  int line, const char *const message, ...) {
+  va_list args;
+  va_start(args, message);
+  logger_log_vaargs(logger, LOG_ERROR, file, function, line, message, args);
+  va_end(args);
+}
-- 
2.48.1