From 58d405b3975043e8680a28741eae38a20af0babe Mon Sep 17 00:00:00 2001
From: 0x221E <ozdemir.demir@protonmail.com>
Date: Fri, 16 Jan 2026 00:53:35 +0100
Subject: [PATCH] Proj-Rewrite: arena allocator with mmap

---
 .gitmodules  |   3 -
 build.sh     |   1 +
 deps/utils   |   1 -
 ibuild.c     | 700 ---------------------------------------------------
 src/main.c   |  26 ++
 src/memory.c |  68 +++++
 src/memory.h |  42 ++++
 src/utils.c  |  29 +++
 src/utils.h  |  17 ++
 9 files changed, 183 insertions(+), 704 deletions(-)
 delete mode 100644 .gitmodules
 create mode 100755 build.sh
 delete mode 160000 deps/utils
 delete mode 100644 ibuild.c
 create mode 100644 src/main.c
 create mode 100644 src/memory.c
 create mode 100644 src/memory.h
 create mode 100644 src/utils.c
 create mode 100644 src/utils.h

diff --git a/.gitmodules b/.gitmodules
deleted file mode 100644
index 917e069..0000000
--- a/.gitmodules
+++ /dev/null
@@ -1,3 +0,0 @@
-[submodule "deps/utils"]
-	path = deps/utils
-	url = git@github.com:0x221E/utils.git
diff --git a/build.sh b/build.sh
new file mode 100755
index 0000000..a6639d3
--- /dev/null
+++ b/build.sh
@@ -0,0 +1 @@
+gcc -o ibuild src/main.c src/memory.c src/utils.c -fsanitize=address -g -DDEBUG
diff --git a/deps/utils b/deps/utils
deleted file mode 160000
index 07c0bfe..0000000
--- a/deps/utils
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 07c0bfe478b30873ed23e01c4191f082f55371c5
diff --git a/ibuild.c b/ibuild.c
deleted file mode 100644
index 57651d4..0000000
--- a/ibuild.c
+++ /dev/null
@@ -1,700 +0,0 @@
-#define CONFIG_FILE "IBUILD"
-#define MAX_STATEMENTS 50
-#define MAX_TOKENS 200
-#define MAX_FILES_IN_DIR 100
-#define MAX_C_FILES 200
-#define MAX_H_FILES 200
-#define MAX_CPP_FILES 200
-
-#include "deps/utils/src/arena_alloc.h"
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/wait.h>
-#include <unistd.h>
-#include <string.h>
-#include <errno.h>
-#include <stdarg.h>
-#include <assert.h>
-#include <dirent.h>
-
-#define DIE(fmt, ...) die_t(__func__, __LINE__, fmt, ##__VA_ARGS__)
-#define LOG_ERROR(fmt, ...) log_write(__func__, fmt, ## __VA_ARGS__)
-#define LOG_USER(fmt, ...) log_write(NULL, fmt, ## __VA_ARGS__)
-
-/*** allocated memory ***/
-// There shall never be another heap allocation outside of thy block.
-// Each system and/or type of allocation shall have its own memory.
-// There shall be no arena managed in this state, if the allocated memory is redundant and will not affect performance.
-// Arenas shall never be arena_free'd during program execution, only before exit. Use arena_reset if you wish to achieve
-// the same functionality without free() calls.
-
-typedef struct
-{
-  Arena file_contents;
-  Arena configuration;
-  Arena strings;
-  Arena parser;
-  Arena discovery;
-} Memory;
-
-static Memory memory;
-
-void memory_free()
-{
-  arena_free(&memory.file_contents);
-  arena_free(&memory.configuration);
-  arena_free(&memory.strings);
-  arena_free(&memory.parser);
-  arena_free(&memory.discovery);
-}
-
-/*** logging  ***/
-
-// Developer-reporting error interface, along with steps to reproduce the error.
-// Include this log in your issues
-void die_t(const char* func, int line, const char* fmt, ...)
-{
-  assert(func != NULL);
-  assert(fmt != NULL);
-  va_list args;
-  va_start(args, fmt);
-  printf("ibuild exception(f:%s-l:%d): ", func, line);
-  vprintf(fmt, args);
-  printf("\n");
-  printf("******Last syscall error: %s\n", strerror(errno));
-  va_end(args);
-  exit(1);
-}
-
-// User-reporting interface
-// func_name: MSG
-void log_write(const char* func, const char* fmt, ...)
-{
-  if(fmt == NULL) DIE("fmt must not be null!");
-  va_list args;
-  va_start(args, fmt);
-  if(func != NULL)
-    printf("%s: ", func);
-  vprintf(fmt, args);
-  printf("\n");
-  va_end(args);      
-}
-
-/*** file management ***/
-
-typedef struct
-{
-  const char* path;
-  unsigned char type;
-} DirEntry;
-
-int dirent_get_next(DIR *d, DirEntry *e, const char *p)
-{
-  assert(d != NULL);
-
-  struct dirent* file = readdir(d);
-  if(file == NULL)
-    return 1;
-
-  switch(file->d_type)
-  {
-  case DT_DIR:
-    e->type = DT_DIR;
-    break;
-  case DT_REG:
-    e->type = DT_REG;
-    break;
-  default:
-    return 1;
-  }
-
-  size_t fs = strlen(file->d_name);
-  char* buf = (char*)arena_alloc(&memory.strings, fs + 1);
-  memcpy(buf, file->d_name, fs + 1);
-  buf[fs] = '\0';
-  e->path = buf;
-  return 0;
-}
-
-size_t dirent_get_recursive(const char* p)
-{
-  if(p == NULL) DIE("p must not be NULL");
-  DIR* dir = opendir(p);
-  DirEntry current;
-
-  size_t count = 0;
-  
-  while(dirent_get_next(dir, &current, p) == 0)
-  {
-    if(current.type == DT_DIR && (strcmp(current.path, ".") == 0 || strcmp(current.path, "..") == 0 || strcmp(current.path, ".git") == 0))
-	continue;
-
-    DirEntry* ptr = (DirEntry*)arena_alloc(&memory.discovery, sizeof(DirEntry));
-    size_t size = strlen(current.path) + 2 + strlen(p);
-    char* buf = (char*)arena_alloc(&memory.strings, size);
-    snprintf(buf, size, "%s/%s", p, current.path);
-    current.path = buf;
-    *ptr = current;
-
-    count++;
-    if(current.type == DT_DIR)
-    {      
-      count += dirent_get_recursive(buf);
-      continue;
-    }
-  }
-  
-  closedir(dir);
-  return count;
-}
-
-long file_get_size(FILE* fd)
-{
-  if(fd == NULL) DIE("fd cannot be NULL.");
-  if(fseek(fd, 0, SEEK_END) != 0) DIE("file exists, fseek SEEK_END fail.");
-  long size = ftell(fd);
-  if(fseek(fd, 0, SEEK_SET) != 0) DIE("file exists, fseek SEEK_SET fail.");
-  return size;
-}
-
-char* file_get_content(Arena* a, const char* fp)
-{
-  if(fp == NULL) DIE("fp cannot be NULL");
-  FILE* fd = fopen(fp, "r");
-  long size = file_get_size(fd);
-  char* buf = (char*)arena_alloc(a, size + 1);
-  size_t ret = fread(buf, size, 1, fd);
-  if (ret != 1) DIE("fread returned %d", ret);
-  buf[size] = '\0';
-  return buf;
-}
-
-bool file_has_r_access(const char* f)
-{
-  if(access(f, F_OK | R_OK) == 0)
-    return true;
-  return false;
-}
-
-/*** discovery phase ***/
-
-typedef struct
-{
-  DirEntry** c_files;
-  DirEntry** h_files;
-  DirEntry** cpp_files;
-  DirEntry** o_files;
-} Discovery;
-
-void discover(Discovery *d)
-{
-  size_t amount = dirent_get_recursive(".");
-  if(amount == 0) DIE("Directory is empty! If you have symlinks in the directory, ibuild does not support them.");
-
-  size_t c_c = 0;
-  size_t h_c = 0;
-  size_t cpp_c = 0;
-  
-  for(size_t i = 0; i < amount; i++)
-  {
-    char* current = NULL;
-    if((current = strrchr(((DirEntry*)memory.discovery.start)[i].path, '.')) == NULL)
-      continue;
-
-    DirEntry* current_dirent = &((DirEntry*)memory.discovery.start)[i];
-    
-    if(strcmp(current, ".c") == 0)
-    {
-      if(c_c > MAX_C_FILES)
-	DIE("Maximum C file limit was reached with the ibuild project. To extend, you must edit the source code and decide whether there is enough memory.");
-
-      d->c_files[c_c] = current_dirent;
-      c_c++;
-    }
-    else if(strcmp(current, ".h") == 0)
-    {
-      if(h_c > MAX_H_FILES)
-	DIE("Maximum H file limit was reached with the ibuild project. To extend, you must edit the source code and decide whether there is enough memory.");
-
-      d->h_files[h_c] = current_dirent;
-      h_c++;
-      
-    }else if(strcmp(current, ".cpp") == 0)
-    {
-      if(cpp_c > MAX_CPP_FILES)
-	DIE("Maximum CPP file limit was reached with the ibuild project. To extend, you must edit the source code and decide whether there is enough memory.");
-
-      d->cpp_files[cpp_c] = current_dirent;
-      cpp_c++;
-    }
-  }
-
-  LOG_USER("Found %d C files, %d H files, %d CPP files.", c_c, h_c, cpp_c);
-}
-
-/*** compilation process ***/
-
-typedef struct
-{
-  char* compiler_path;
-  char* build_dir;
-  char* target_exec;
-  char* src_dir;
-  char** src_files;
-  char* version;
-  char* dep_searcher;
-  char* dep_searcher_flags;
-} Configuration;
-
-void launch_compile(Configuration* co)
-{
-  if(co == NULL) DIE("co has to be valid");
-  if(co->compiler_path == NULL) DIE("requires a valid compiler path");
-
-  int fildes[2];
-  pipe(fildes);
-  pid_t p = fork();
-
-  if(p<0)
-  {
-    DIE("fork error");
-  }
-  else if (p==0)
-  {
-    char* args[] = {co->compiler_path, "ibuild.c", "-o", co->target_exec, NULL};
-    close(STDOUT_FILENO);
-    dup(fildes[1]);
-    close(fildes[0]);
-    close(fildes[1]);
-    
-    if((execvp(co->compiler_path, args)) == -1)
-      DIE("launch_compile() execvp error");
-    exit(0);
-  }
-}
-
-/*** configuration lexer ***/
-
-typedef struct
-{
-  char *src;
-} Tokenizer;
-
-typedef enum
-{
-  T_INVALID = -1,
-  T_IDENTIFIER = 0,
-  T_STRING = 1,
-  T_IS = 2,
-  T_EOF = 3,
-} TokenType;
-
-typedef struct
-{
-  TokenType type;
-  char* value;
-  int line;
-} Token;
-
-#define TOKEN_CONST {T_INVALID, NULL, 0}
-
-bool is_alpha_uppercase(char s)
-{
-  return (s >= 'A' && s <= 'Z');
-}
-
-bool is_alpha_lowercase(char s)
-{
-  return (s >= 'a' && s <= 'z');
-}
-
-bool is_whitespace(char s)
-{
-  return s == ' ' || s == '\t' || s == '\r' || s == '\n';
-}
-
-bool is_part_of_key(char s)
-{
-  return is_alpha_uppercase(s) || s == '_';
-}
-
-size_t skip_group(Tokenizer* t, bool (*func)(char))
-{
-  assert(func != NULL);
-  size_t len = 0;
-  while(func(*t->src))
-  {
-    len++;
-    t->src += 1;
-  }
-  return len;
-}
-
-Token tokenize_identifier(Tokenizer *t)
-{
-  char* temp = t->src;
-  size_t len = skip_group(t, &is_part_of_key);
-  char* buf = (char*)arena_alloc(&memory.strings, sizeof(char) * len + 1);
-  memcpy(buf, temp, len);
-  buf[len] = '\0';
-  return (Token){T_IDENTIFIER, buf};
-}
-
-Token tokenize_string(Tokenizer *t)
-{
-  t->src += 1;
-  char* temp = t->src;
-  size_t len = 0;
-
-  while(*t->src != '"' && *t->src != '\0')
-  {
-    len++;
-    t->src += 1;
-  }
-
-  if(*t->src == '"') t->src++;
-  
-  char* buf = (char*)arena_alloc(&memory.strings, (sizeof(char) * len) + 1);
-  memcpy(buf, temp, len);
-  buf[len] = '\0';
-  return (Token){T_STRING, buf};
-}
-
-Token tokenizer_next(Tokenizer* t)
-{
-  if(is_whitespace(*t->src)) skip_group(t, &is_whitespace);
-
-  if(is_alpha_uppercase(*t->src))
-  {
-    return tokenize_identifier(t);
-  }
-
-  switch(*t->src)
-  {
-  case '"':
-    return tokenize_string(t);
-  case '=':
-    t->src++;
-    return (Token){T_IS, NULL};
-  }
-
-  if(*t->src == '\0') return (Token){T_EOF, NULL};
-
-  t->src++;
-  return (Token){T_INVALID, NULL};
-}
-
-size_t tokenizer_tokenize(Tokenizer* t, Token* ts)
-{
-  size_t t_count = 0;
-  while(1)
-  {
-    if(t_count > MAX_TOKENS) DIE("Maximum number of tokens reached! \n Could not read configuration file.");   
-    Token token = tokenizer_next(t);
-    if(token.type == T_INVALID) DIE("illegal token!");
-    ts[t_count] = token;
-    t_count++;
-    if(token.type == T_EOF) break;
-  }
-  return t_count;
-}
-
-/*** configuration parser ***/
-
-typedef enum
-{
-  K_NA = -1,
-  K_UNKNOWN = 0,
-  K_COMPILER_PATH = 1,
-  K_SRC_DIR = 2,
-  K_SRC_FILES = 3,
-  K_BUILD_DIR = 4,
-  K_TARGET_EXEC = 5,
-  K_DEP_SEARCHER = 6,
-  K_DEP_SEARCHER_FLAGS = 7,
-  K_VERSION = 8,
-} Key;
-
-typedef enum
-{
-  N_STRING = 0,
-  N_ARRAY = 1,
-  N_PAIR = 2,
-} NodeType;
-
-typedef struct
-{
-  NodeType type;
-  Key key;
-  void* value;
-} Node;
-
-typedef struct
-{
-  Token* tokens;
-  size_t loc;
-  size_t cap;
-} Parser;
-
-typedef struct
-{
-  Key key;
-  const char* value;
-} KeyMap;
-
-static KeyMap keyword_mappings[] = {
-  {K_COMPILER_PATH, "COMPILER_PATH"},
-  {K_SRC_DIR, "SRC_DIR"},
-  {K_SRC_FILES, "SRC_FILES"},
-  {K_BUILD_DIR, "BUILD_DIR"},
-  {K_TARGET_EXEC, "TARGET_EXEC"},
-  {K_DEP_SEARCHER, "DEP_SEARCHER"},
-  {K_DEP_SEARCHER_FLAGS, "DEP_SEARCHER_FLAGS"},
-  {K_UNKNOWN, NULL},
-};
-
-Key key_lookup(char* s)
-{
-  if(s == NULL) return K_UNKNOWN;
-  
-  for(const KeyMap* ptr = keyword_mappings; ptr->value != NULL; ptr++)
-  {
-    if(strcmp(ptr->value, s) == 0)
-    {
-      return ptr->key;
-    }
-  }
-  return K_UNKNOWN;
-}
-
-Token parser_peek(Parser* p, size_t o)
-{
-  if (p->loc + o >= p->cap)
-  {
-    return p->tokens[p->loc - 1];
-  }
-  Token t = p->tokens[p->loc + o];
-  return t;
-}
-
-Token parser_previous(Parser* p)
-{
-  if(p->loc - 1 < 0)
-  {
-    DIE("parser logic error.");
-  }
-
-  return p->tokens[p->loc - 1];
-}
-
-Token parser_advance(Parser* p)
-{
-  if(p->loc + 1 >= p->cap)
-  {
-    return p->tokens[p->loc];
-  }
-  p->loc++;
-  return p->tokens[p->loc];
-}
-
-Token parser_expect(Parser* p, TokenType tt, char* s)
-{
-  assert(p != NULL);
-  assert(s != NULL); 
-
-  if(parser_peek(p, 1).type != tt)
-     DIE(s);
-
-  return parser_advance(p);
-}
-
-Node* parser_expression(Parser* p)
-{
-  Token t = parser_advance(p);
-  if(t.type == T_STRING)
-  {
-    Node* node = (Node*)arena_alloc(&memory.parser, sizeof(Node));
-    node->key = K_NA;
-    node->value = (void*)t.value;
-    node->type = N_STRING;
-    parser_advance(p);
-    return node;
-  }
-
-  DIE("Syntax error: Invalid expression.");
-}
-
-Node* parser_statement(Parser* p)
-{
-  Token t = parser_peek(p, 0);
-  if(t.type == T_IDENTIFIER)
-  {
-    Key k = key_lookup(t.value);
-    if(k == K_UNKNOWN) DIE("Syntax error: Unexpected identifer encountered");
-    parser_expect(p, T_IS, "Syntax error: Expected '=' after identifier");
-    Node* expression = parser_expression(p);
-    Node* node = (Node*)arena_alloc(&memory.parser, sizeof(Node));
-    node->key = k;
-    node->value = (void*)expression;
-    node->type = N_PAIR;
-    return node;
-  }
-  else
-  {
-   DIE("Syntax error: expected an identifier, got: %d", t.type);
-  }
-}
-
-Node* parser_parse_next(Parser* p)
-{
-  return parser_statement(p);
-}
-
-size_t parser_parse(Parser* p, Node** s)
-{
-  assert(p != NULL);
-  assert(s != NULL);
-  
-  size_t p_count = 0;
-
-  while(p_count < MAX_STATEMENTS && p->loc < p->cap - 1)
-  {
-    s[p_count] = parser_parse_next(p);
-    p_count++;
-  }
-  return p_count;
-}
-
-#ifdef DEBUG
-
-void debug_parser(Node* n, int indent)
-{
-  for(int i = 0; i < indent; i++)
-  {
-    printf(" ");
-  }
-  
-  switch(n->type)
-  {
-  case N_PAIR:
-    printf("PAIR STATEMENT");
-    printf("    Key: %10d\n", n->key);
-    if(n->value != NULL)
-      debug_parser((Node*)n->value, 2);
-    break;
-  case N_STRING:
-    printf("STRING EXPRESSION");
-    printf("     Value: %s\n", (char*)n->value);
-    break;
-  }
-}
-
-#endif
-
-/*** configuration process ***/
-
-void configuration_set_option(Configuration* co, Key k, char* val)
-{
-  switch(k)
-  {
-  case K_NA: DIE("Node with an NA key hit configuration_set_option"); break;
-  case K_UNKNOWN: DIE("Unknown node encountered!"); break;
-  case K_COMPILER_PATH: co->compiler_path = val; break;
-  case K_BUILD_DIR: co->build_dir = val; break;
-  case K_TARGET_EXEC: co->target_exec = val; break;
-  case K_DEP_SEARCHER: co->dep_searcher = val; break;
-  case K_DEP_SEARCHER_FLAGS: co->dep_searcher_flags = val; break;
-  case K_VERSION: co->version = val; break;
-  case K_SRC_DIR: co->src_dir = val; break;	
-  case K_SRC_FILES: DIE("Not implemented!"); break;
-  default:
-    DIE("Invalid compiler option was supplied!");
-  }
-}
-
-void configuration_process_node(Configuration* co, Node* n)
-{
-  switch(n->type)
-  {
-  case N_PAIR:
-    Key k = n->key;
-    configuration_set_option(co, k, (char*)((Node*)n->value)->value);
-    break;
-  }
-}
-
-Configuration configuration_struct_setup(int len, Node** st)
-{
-  Configuration config;
-  config.compiler_path = "/usr/bin/gcc";
-  config.build_dir = ".";
-  config.src_dir = ".";
-  config.target_exec = "iexec";
-  config.dep_searcher = "/usr/bin/gcc";
-  config.dep_searcher_flags = "-MM";
-
-  for (size_t i = 0; i < len; i++)
-    configuration_process_node(&config, st[i]);
-  
-  LOG_USER("Configured IBUILD options.");
-  return config;
-}
-
-/*** configuration file management ***/
-
-Configuration process_config(const char* fn)
-{
-  if(!file_has_r_access(fn))
-  {
-     return configuration_struct_setup(0, NULL);
-  }
-  
-  LOG_USER("IBUILD Configuration file detected.\n");
-  char* config_mem = file_get_content(&memory.file_contents, fn);
-    
-  Token tokens[MAX_TOKENS];
-  Tokenizer t = { .src = config_mem };
-
-  size_t t_count = tokenizer_tokenize(&t, tokens);
-
-  if(t_count == 0)
-  {
-    return configuration_struct_setup(0, NULL);
-  }      
-  
-  Parser parser = {.tokens = tokens, .loc = 0, .cap = t_count };  
-  Node* statements[MAX_STATEMENTS];
-  size_t p_count = parser_parse(&parser, statements);
-  
-#ifdef DEBUG
-  
-  for (size_t i = 0; i < p_count; i++)
-    debug_parser(statements[i], 0);
-
-#endif
-
-  return configuration_struct_setup(p_count, statements);  
-}
-
-#ifndef TESTING
-int main(int argc, char** argv)
-{
-  LOG_USER("Build version: %s", VERSION);
-  Configuration c = process_config(CONFIG_FILE);
-
-  dirent_get_recursive(".");
-
-  Discovery d;
-  d.c_files = (DirEntry**)arena_alloc(&memory.discovery, MAX_C_FILES * sizeof(DirEntry*));
-  d.h_files = (DirEntry**)arena_alloc(&memory.discovery, MAX_H_FILES * sizeof(DirEntry*));
-  discover(&d);
-
-  // Hand over discovery to the dependency checker.
-
-  // Compile
-  //launch_compile(&c);
-  memory_free();
-  return 0;
-}
-#endif
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..393f6ac
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,26 @@
+#include "memory.h"
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "utils.h"
+
+int main(void) {
+  Backend b = {NULL, 0};
+  backend_initialize(&b);
+  
+  Arena a;
+  a.b = &b;
+
+  char* test = (char*)arena_alloc(&a, 6);
+  char* test2 = "Noice";
+
+  memcpy(test, test2, 5);
+
+  test[5] = '\0';
+  
+  printf("That's right. %s\n", test);
+
+  return 0;
+}
diff --git a/src/memory.c b/src/memory.c
new file mode 100644
index 0000000..9f86164
--- /dev/null
+++ b/src/memory.c
@@ -0,0 +1,68 @@
+#include "memory.h"
+#include "utils.h"
+
+#include <assert.h>
+#include <sys/mman.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+void backend_initialize(Backend* b)
+{
+  assert(b != NULL);
+  size_t cap = MEM_BACKEND_MAX_CAP;
+  void* mem = mmap(NULL, cap, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  if(mem == MAP_FAILED) DIE("mmap failed!");
+  b->mem = mem;
+  b->last = b->mem;
+  b->len = 0;
+  b->cap = cap;
+}
+
+void backend_free(Backend* b)
+{
+  if(munmap(b->mem, b->cap) == -1) DIE("munmap failed!");
+}
+
+void* backend_reserve(Backend* b)
+{
+  assert(b != NULL);
+  void* ptr = b->last;
+  if(b->len + MEM_ARENA_MAX_CAP >= MEM_BACKEND_MAX_CAP)
+    DIE("Out of memory, requested %d (current usage %d out of %d).", MEM_ARENA_MAX_CAP, b->len, b->cap);
+  b->last = (char*)b->last + (int)MEM_ARENA_MAX_CAP;
+  b->len += MEM_ARENA_MAX_CAP;
+  return ptr;
+}
+
+void arena_init(Arena* a)
+{
+  assert(a != NULL);
+  assert(a->b != NULL);
+  void* mem = backend_reserve(a->b);
+  a->mem = mem;
+  a->cap = MEM_ARENA_MAX_CAP;
+  a->len = 0;
+  a->last = a->mem;
+  a->next = NULL;
+  LOG_DEBUG("Arena initialized with block @ %p.", a->mem);
+}
+
+void* arena_alloc(Arena* a, size_t len)
+{
+  assert(a != NULL);
+  assert(a->b != NULL);
+  if(a->mem == NULL || a->last == NULL) arena_init(a);
+
+  int len_aligned = (len + 7) & ~7;
+
+  if(a->len + len_aligned > a->cap)
+  {
+    DIE("Arena exceeded memory, requested: %d (%d out of %d used)", len, a->len, a->cap);
+  }
+
+  void* res = a->last;
+  a->len = len_aligned + a->len;
+  a->last = (char*)a->last + len_aligned;
+  LOG_DEBUG("Arena with block @ %p, allocated %d bytes of memory, arena last is now @ %p.", a->mem, len_aligned, a->last);
+  return res;
+}
diff --git a/src/memory.h b/src/memory.h
new file mode 100644
index 0000000..1e665bf
--- /dev/null
+++ b/src/memory.h
@@ -0,0 +1,42 @@
+#ifndef MEMORY_H
+#define MEMORY_H
+
+
+#ifndef MEM_ARENA_MAX_CAP
+#define MEM_ARENA_MAX_CAP 1024 * 1024
+#endif
+
+#ifndef MEM_BACKEND_MAX_CAP
+#define MEM_BACKEND_MAX_CAP 1024 * 1024 * 256
+#endif
+
+#include <stddef.h>
+
+typedef struct
+{
+  void* mem;
+  void* last;
+  size_t len;
+  size_t cap;
+} Backend;
+
+typedef struct
+{
+  void* mem;
+  void* last;
+  size_t len;
+  size_t cap;
+  void* next;
+  Backend* b;
+} Arena;
+
+void backend_initialize(Backend* b);
+void backend_free(Backend* b);
+
+void* backend_reserve(Backend* b);
+
+void arena_init(Arena* a);
+//void arena_reset(Arena* a);
+void* arena_alloc(Arena* a, size_t len);
+
+#endif
diff --git a/src/utils.c b/src/utils.c
new file mode 100644
index 0000000..f5fbbd8
--- /dev/null
+++ b/src/utils.c
@@ -0,0 +1,29 @@
+#include "utils.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stddef.h>
+#include <string.h>
+#include <stdlib.h>
+
+void die_f(const char* func, int l, const char* fmt,...)
+{
+  va_list args;
+  va_start(args);
+  printf("IBUILD Error (%d:%s): ", l, func);
+  vprintf(fmt, args);
+  printf("\nlast syscall error: \n", strerror(errno));
+  va_end(args);
+  exit(1);
+}
+
+void log_f(const char* func, int l, const char* fmt, ...)
+{
+  va_list args;
+  va_start(args);
+  printf("IBUILD Log (%d:%s): ", l, func);
+  vprintf(fmt, args);
+  printf("\n");
+  va_end(args);
+}
diff --git a/src/utils.h b/src/utils.h
new file mode 100644
index 0000000..c522986
--- /dev/null
+++ b/src/utils.h
@@ -0,0 +1,17 @@
+#ifndef UTILS_H
+#define UTILS_H
+
+#define DIE(fmt, ...) die_f(__func__, __LINE__, fmt, ## __VA_ARGS__)
+
+#define LOG(fmt, ...) log_f(__func__, __LINE__, fmt, ## __VA_ARGS__)
+
+#ifdef DEBUG
+#define LOG_DEBUG(fmt, ...) log_f(__func__, __LINE__, fmt, ## __VA_ARGS__)
+#else
+#define LOG_DEBUG(...)
+#endif
+
+void die_f(const char* func, int l, const char* fmt, ...);
+void log_f(const char* func, int l, const char* fmt, ...);
+
+#endif