file utility

src/file.c

@@ -0,0 +1,62 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "types.h"
+
+void update_file_time(File *file) {
+  struct stat attr;
+  if (stat(file->path, &attr) == 0) {
+    file->last_write = attr.st_mtime;
+  }
+}
+
+bool should_update_file(File *file) {
+  struct stat attr;
+  if (stat(file->path, &attr) == 0) {
+    return file->last_write != attr.st_mtime;
+  }
+  return false;
+}
+
+void update_file(File *file) {
+  // free remaining data
+  free(file->content);
+  // init empty file
+  file->content = 0;
+  file->error = false;
+  long length;
+  // open file
+  FILE *file_pointer = fopen(file->path, "rb");
+  if (!file_pointer) {
+    file->error = true;
+    return;
+  }
+  // read file length
+  fseek(file_pointer, 0, SEEK_END);
+  length = ftell(file_pointer);
+  // init buffer
+  fseek(file_pointer, 0, SEEK_SET);
+  file->content = (char *)malloc((length + 1) * sizeof(char));
+  if (!file->content) {
+    file->error = true;
+    fclose(file_pointer);
+    return;
+  }
+  // read file
+  fread(file->content, sizeof(char), length, file_pointer);
+  // close file
+  fclose(file_pointer);
+  // append null byte
+  file->content[length] = '\0';
+  // read last update time
+  update_file_time(file);
+}
+
+File read_file(char *path) {
+  File file = {path, 0, 0, 0};
+  update_file(&file);
+  return file;
+}

src/file.h

@@ -0,0 +1,12 @@
+#include "types.h"
+
+#ifndef FILE_H
+#define FILE_H
+
+File read_file(char *path);
+
+bool should_update_file(File *file);
+
+void update_file(File *file);
+
+#endif

src/types.h

@@ -1,5 +1,7 @@
 #include <glad/gl.h>
 #include <linmath.h>
+#include <stdbool.h>
+#include <time.h>
 
 #ifndef TYPES_H
 #define TYPES_H
@@ -12,6 +14,13 @@ typedef struct Vertex {
   vec2 pos;
 } Vertex;
 
+typedef struct File {
+  char *path;
+  char *content;
+  bool error;
+  time_t last_write;
+} File;
+
 typedef struct ShaderProgram {
   GLuint program;