README: updated for new malloc and directory structure

.gitignore

@@ -1,7 +1,9 @@
 *
 !.gitignore
-!*.c
-!*.h
 !*.md
 !LICENSE
 !Makefile
+!/src
+!/src/*.c
+!/include
+!/include/*.h

Makefile

@@ -1,47 +1,45 @@
-CC     = gcc
-CFLAGS = -O3 -Wall -Wextra -Wpedantic
+CC       = gcc
+CFLAGS   =
+CPPFLAGS = -Iinclude -MMD -MP
 
-SRCS = main.c vm.c gc.c galloc.c
-OBJS = $(SRCS:.c=.o)
+SRCDIR = src
+
+SRCS = $(wildcard $(SRCDIR)/*.c)
+OBJS = $(patsubst $(SRCDIR)/%.c,%.o,$(SRCS))
 EXE  = gc
 
-DBDIR     = debug
-DBEXE     = $(DBDIR)/$(EXE)
-DBOBJS    = $(addprefix $(DBDIR)/, $(OBJS))
-DBCFLAGS  = -g -O0 -DDEBUG
+DBDIR    = debug
+DBEXE    = $(DBDIR)/$(EXE)
+DBOBJS   = $(addprefix $(DBDIR)/, $(OBJS))
+DBCFLAGS = -g -O0 -DDEBUG
 
-REDIR     = build
-REEXE     = $(REDIR)/$(EXE)
-REOBJS    = $(addprefix $(REDIR)/, $(OBJS))
+REDIR    = bin
+REEXE    = $(REDIR)/$(EXE)
+REOBJS   = $(addprefix $(REDIR)/, $(OBJS))
+RECFLAGS = -O3 -Wall -Wextra -Wpedantic -Werror
 
-.PHONY: all clean debug release prep
+.PHONY: all clean debug prep release
 
-all: debug release gc
-
-gc: $(REEXE)
-	@cp $< $@
+all: debug release
 
 debug: prep $(DBEXE)
 
 $(DBEXE): $(DBOBJS)
-	$(CC) $(CFLAGS) $(DBCFLAGS) -DTEST -o $@ $^
+	$(CC) $(CFLAGS) $(DBCFLAGS) -o $@ $^
 
-$(DBDIR)/%.o: %.c
-	$(CC) -c $(CFLAGS) $(DBCFLAGS) -o $@ $<
+$(DBDIR)/%.o: $(SRCDIR)/%.c
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $(DBCFLAGS) -o $@ $<
 
 release: prep $(REEXE)
 
 $(REEXE): $(REOBJS)
-	$(CC) $(CFLAGS) -o $@ $^
+	$(CC) $(CFLAGS) $(RECFLAGS) -o $@ $^
 
-$(REDIR)/%.o: %.c
-	$(CC) -c $(CFLAGS) -o $@ $<
+$(REDIR)/%.o: $(SRCDIR)/%.c
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $(RECFLAGS) -o $@ $<
 
 prep:
 	@mkdir -p $(DBDIR) $(REDIR)
 
 clean:
-	rm -rf gc $(DBDIR) $(REDIR)
-
-
-
+	rm -rf $(DBDIR) $(REDIR)

README.md

@@ -1,38 +1,44 @@
 # marCsweep
 
-A mark-and-sweep garbage collector with a simple virtual machine to perform
-allocations.
+A mark-and-sweep garbage collector written in C. 
+
+Includes a simple virtual machine and a custom `malloc` implementation
+for creating, tracing, and freeing garbage.
 
 ## Building
 
 Compiling the project should be relatively easy, even if you aren't familiar
 with `make`.
 
-Dependencies: `git`, `make`, and `gcc`. Compiling with `clang` is also possible,
-simply replace "gcc" with "clang" in the first line of the Makefile.
+Dependencies: `git`, `make`, and `gcc`.
 
 ```
 git clone https://codeberg.org/andyscott/marCsweep.git
 
 cd marCsweep
 
-make release
+make release # or debug
 ```
 
-That's it! The Makefile will automatically create the build directory and place
-the compiled executable there.
+That's it! Make will create the `bin` directory and place the finished
+executable there.
+
+Compiling with `clang` is also supported, just replace "gcc" with "clang" in the
+first line of the `Makefile`. Also note that if you don't specify a target for
+make (i.e. "release" or "debug") both will be built. Debug builds are placed in
+the `debug` directory.
 
 ## Running
 
 Once compiled, the program can be run with the following:
 
 ```
-cd build # or debug
+cd bin # or debug
 
 ./gc
 ```
 
-By default the program will output the results of the test cases:
+The results of the test cases will be output to your terminal:
 
 > test_int_alloc: PASS  
 test_pair_alloc: PASS  
@@ -49,4 +55,8 @@ should be ready for experimentation!
 This is a personal project that I am writing in my free time to learn more about
 garbage collection. Thank you to [Robert
 Nystrom](https://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)
-for the idea.
+for the idea. 
+
+Sadly, it was this author's idea to extend the project by writing a custom
+`malloc`. Perhaps I should have been lazy and used the preexisting definitions,
+but where's the fun in that?

gc.c

@@ -1,44 +0,0 @@
-#include <stdlib.h>
-
-#include "gc.h"
-#include "vm.h"
-
-void mark(struct garbageObject *obj) {
-  if (obj->mark)
-    return;
-
-  ++obj->mark;
-
-  if (obj->type == GARBAGE_PAIR) {
-    mark(obj->head);
-    mark(obj->tail);
-  }
-}
-
-void markAll(struct virtualMachine *vm) {
-  for (int i = 0; i < vm->stackSize; ++i) {
-    mark(vm->stack[i]);
-  }
-}
-
-void sweep(struct virtualMachine *vm) {
-  struct garbageObject **obj = &vm->head;
-
-  while (*obj) {
-    if (!(*obj)->mark) {
-      struct garbageObject *unreachable = *obj;
-      *obj = unreachable->next;
-      free(unreachable);
-      vm->refCount--;
-    } else {
-      (*obj)->mark = 0;
-      obj = &(*obj)->next;
-    }
-  }
-}
-
-void collect(struct virtualMachine *vm) {
-  markAll(vm);
-  sweep(vm);
-  vm->refMax = vm->refCount * 2 <= STACK_MAX ? vm->refCount * 2 : STACK_MAX;
-}

include/gc_alloc.h

@@ -1,5 +1,5 @@
-#ifndef GALLOC_H
-#define GALLOC_H
+#ifndef GC_ALLOC_H
+#define GC_ALLOC_H
 
 #include <stdio.h>
 
@@ -23,4 +23,4 @@ void *galloc(size_t size);
 // Frees memory allocated with galloc()
 void gfree(void *ptr);
 
-#endif /* GALLOC_H */
+#endif /* GC_ALLOC_H */

main.c

@@ -1,107 +0,0 @@
-#include <assert.h>
-#include <stdio.h>
-
-#include "gc.h"
-#include "test_gc.h"
-#include "vm.h"
-
-void test_int_alloc(void) {
-  struct virtualMachine *vm = initVM();
-  pushInt(vm, 100);
-  pushInt(vm, 1000);
-  pushInt(vm, 10000);
-  pushInt(vm, -100000);
-  assert(vm->refCount == 4 &&
-         "test_int_alloc: GARBAGE_INT allocation failure\n");
-  printf("test_int_alloc: PASS\n");
-  deinitVM(vm);
-}
-
-void test_pair_alloc(void) {
-  struct virtualMachine *vm = initVM();
-  pushInt(vm, 100);
-  pushInt(vm, 1000);
-  pushInt(vm, 10000);
-  pushInt(vm, -100000);
-  pushPair(vm);
-  pushPair(vm);
-  assert(vm->refCount == 6 &&
-         "test_pair_alloc: FAILED: GARBAGE_PAIR allocation failure\n");
-  printf("test_pair_alloc: PASS\n");
-  deinitVM(vm);
-}
-
-void test_obj_count(void) {
-  struct virtualMachine *vm = initVM();
-  pushInt(vm, 100);
-  pushInt(vm, 1000);
-  pushInt(vm, 10000);
-  pushInt(vm, -100000);
-  collect(vm);
-  assert(vm->refCount == 4 &&
-         "test_obj_count: FAILED: GC occurred when it shouldn't have\n");
-  printf("test_obj_count: PASS\n");
-  deinitVM(vm);
-}
-
-void test_nested_pair(void) {
-  struct virtualMachine *vm = initVM();
-  pushInt(vm, 100);
-  pushInt(vm, 1000);
-  pushPair(vm);
-  pushInt(vm, 10000);
-  pushInt(vm, -100000);
-  pushPair(vm);
-  pushPair(vm);
-  collect(vm);
-  assert(vm->refCount == 7 &&
-         "test_nested_pair: FAILED: GARBAGE_PAIR allocation failure\n");
-  printf("test_pair_alloc: PASS\n");
-  deinitVM(vm);
-}
-
-void test_unreachable(void) {
-  struct virtualMachine *vm = initVM();
-  pushInt(vm, 100);
-  pushInt(vm, 1000);
-  pop(vm);
-  pop(vm);
-  collect(vm);
-  assert(vm->refCount == 0 &&
-         "test_unreachable: FAILED: 2 GARBAGE_INT should have been freed\n");
-  printf("test_unreachable: PASS\n");
-  deinitVM(vm);
-}
-
-void test_auto_gc(void) {
-  struct virtualMachine *vm = initVM();
-
-  for (size_t i = 0; i < 505; ++i) {
-    pushInt(vm, 1);
-  }
-
-  for (size_t i = 0; i < 5; ++i) {
-    pop(vm);
-  }
-
-  for (size_t i = 0; i < 50; ++i) {
-    pushInt(vm, 2);
-  }
-
-  assert(vm->refCount == 550 &&
-         "test_auto_gc: FAILED: 5 references should have been freed\n");
-  printf("test_auto_gc: PASS\n");
-  deinitVM(vm);
-}
-
-int main(void) {
-
-  test_int_alloc();
-  test_pair_alloc();
-  test_obj_count();
-  test_nested_pair();
-  test_unreachable();
-  test_auto_gc();
-
-  return 0;
-}

src/gc.c

@@ -0,0 +1,47 @@
+#include <stdlib.h>
+
+#include "gc.h"
+
+void mark(struct garbageObject *obj)
+{
+    if (obj->mark)
+        return;
+
+    ++obj->mark;
+
+    if (obj->type == GARBAGE_PAIR) {
+        mark(obj->head);
+        mark(obj->tail);
+    }
+}
+
+void markAll(struct virtualMachine *vm)
+{
+    for (int i = 0; i < vm->stackSize; ++i) {
+        mark(vm->stack[i]);
+    }
+}
+
+void sweep(struct virtualMachine *vm)
+{
+    struct garbageObject **obj = &vm->head;
+
+    while (*obj) {
+        if (!(*obj)->mark) {
+            struct garbageObject *unreachable = *obj;
+            *obj = unreachable->next;
+            free(unreachable);
+            vm->refCount--;
+        } else {
+            (*obj)->mark = 0;
+            obj = &(*obj)->next;
+        }
+    }
+}
+
+void collect(struct virtualMachine *vm)
+{
+    markAll(vm);
+    sweep(vm);
+    vm->refMax = vm->refCount * 2 <= STACK_MAX ? vm->refCount * 2 : STACK_MAX;
+}

src/main.c

@@ -0,0 +1,114 @@
+#include <assert.h>
+#include <stdio.h>
+
+#include "gc.h"
+#include "test_gc.h"
+#include "vm.h"
+
+void test_int_alloc(void)
+{
+    struct virtualMachine *vm = initVM();
+    pushInt(vm, 100);
+    pushInt(vm, 1000);
+    pushInt(vm, 10000);
+    pushInt(vm, -100000);
+    assert(vm->refCount == 4
+           && "test_int_alloc: GARBAGE_INT allocation failure\n");
+    printf("test_int_alloc: PASS\n");
+    deinitVM(vm);
+}
+
+void test_pair_alloc(void)
+{
+    struct virtualMachine *vm = initVM();
+    pushInt(vm, 100);
+    pushInt(vm, 1000);
+    pushInt(vm, 10000);
+    pushInt(vm, -100000);
+    pushPair(vm);
+    pushPair(vm);
+    assert(vm->refCount == 6
+           && "test_pair_alloc: FAILED: GARBAGE_PAIR allocation failure\n");
+    printf("test_pair_alloc: PASS\n");
+    deinitVM(vm);
+}
+
+void test_obj_count(void)
+{
+    struct virtualMachine *vm = initVM();
+    pushInt(vm, 100);
+    pushInt(vm, 1000);
+    pushInt(vm, 10000);
+    pushInt(vm, -100000);
+    collect(vm);
+    assert(vm->refCount == 4
+           && "test_obj_count: FAILED: GC occurred when it shouldn't have\n");
+    printf("test_obj_count: PASS\n");
+    deinitVM(vm);
+}
+
+void test_nested_pair(void)
+{
+    struct virtualMachine *vm = initVM();
+    pushInt(vm, 100);
+    pushInt(vm, 1000);
+    pushPair(vm);
+    pushInt(vm, 10000);
+    pushInt(vm, -100000);
+    pushPair(vm);
+    pushPair(vm);
+    collect(vm);
+    assert(vm->refCount == 7
+           && "test_nested_pair: FAILED: GARBAGE_PAIR allocation failure\n");
+    printf("test_pair_alloc: PASS\n");
+    deinitVM(vm);
+}
+
+void test_unreachable(void)
+{
+    struct virtualMachine *vm = initVM();
+    pushInt(vm, 100);
+    pushInt(vm, 1000);
+    pop(vm);
+    pop(vm);
+    collect(vm);
+    assert(
+        vm->refCount == 0
+        && "test_unreachable: FAILED: 2 GARBAGE_INT should have been freed\n");
+    printf("test_unreachable: PASS\n");
+    deinitVM(vm);
+}
+
+void test_auto_gc(void)
+{
+    struct virtualMachine *vm = initVM();
+
+    for (size_t i = 0; i < 505; ++i) {
+        pushInt(vm, 1);
+    }
+
+    for (size_t i = 0; i < 5; ++i) {
+        pop(vm);
+    }
+
+    for (size_t i = 0; i < 50; ++i) {
+        pushInt(vm, 2);
+    }
+
+    assert(vm->refCount == 550
+           && "test_auto_gc: FAILED: 5 references should have been freed\n");
+    printf("test_auto_gc: PASS\n");
+    deinitVM(vm);
+}
+
+int main(void)
+{
+    test_int_alloc();
+    test_pair_alloc();
+    test_obj_count();
+    test_nested_pair();
+    test_unreachable();
+    test_auto_gc();
+
+    return 0;
+}

src/vm.c

@@ -0,0 +1,89 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "gc.h"
+#include "vm.h"
+
+struct virtualMachine *initVM(void)
+{
+    struct virtualMachine *vm = malloc(sizeof(struct virtualMachine));
+    vm->stackSize = 0;
+    vm->refCount = 0;
+    vm->refMax = GC_THRESHOLD;
+    vm->head = NULL;
+    return vm;
+}
+
+void deinitVM(struct virtualMachine *vm)
+{
+    vm->stackSize = 0;
+    collect(vm);
+    free(vm);
+}
+
+void push(struct virtualMachine *vm, struct garbageObject *value)
+{
+    if (vm->stackSize >= STACK_MAX) {
+        fprintf(stderr, "ERROR: push(): refusing to overflow the stack!\n");
+        return;
+    }
+    vm->stack[vm->stackSize++] = value;
+}
+
+struct garbageObject *pop(struct virtualMachine *vm)
+{
+    if (vm->stackSize < 0) {
+        fprintf(stderr, "ERROR: pop(): Stack size cannot be negative!");
+        return NULL;
+    }
+
+    return vm->stack[--vm->stackSize];
+}
+
+struct garbageObject *initGarbage(struct virtualMachine *vm,
+                                  enum garbageData type)
+{
+    if (vm->refCount >= vm->refMax) {
+        collect(vm);
+    }
+
+    struct garbageObject *obj = malloc(sizeof(struct garbageObject));
+    if (obj == NULL) {
+        fprintf(stderr, "initGarbage(): Allocation failure!");
+        return obj;
+    }
+
+    obj->type = type;
+    obj->mark = 0;
+    obj->next = vm->head;
+    vm->head = obj;
+    vm->refCount++;
+    return obj;
+}
+
+void pushInt(struct virtualMachine *vm, int value)
+{
+    struct garbageObject *obj = initGarbage(vm, GARBAGE_INT);
+    if (obj == NULL) {
+        fprintf(stderr,
+                "pushInt(): Unable to create GARBAGE_INT - out of memory?");
+    }
+
+    obj->value = value;
+    push(vm, obj);
+}
+
+struct garbageObject *pushPair(struct virtualMachine *vm)
+{
+    struct garbageObject *obj = initGarbage(vm, GARBAGE_PAIR);
+    if (obj == NULL) {
+        fprintf(stderr,
+                "pushPair(): Unable to create GARBAGE_PAIR - out of memory?");
+    }
+
+    obj->tail = pop(vm);
+    obj->head = pop(vm);
+
+    push(vm, obj);
+    return obj;
+}

vm.c

@@ -1,82 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-
-#include "gc.h"
-#include "vm.h"
-
-struct virtualMachine *initVM(void) {
-  struct virtualMachine *vm = malloc(sizeof(struct virtualMachine));
-  vm->stackSize = 0;
-  vm->refCount = 0;
-  vm->refMax = GC_THRESHOLD;
-  vm->head = NULL;
-  return vm;
-}
-
-void deinitVM(struct virtualMachine *vm) {
-  vm->stackSize = 0;
-  collect(vm);
-  free(vm);
-}
-
-void push(struct virtualMachine *vm, struct garbageObject *value) {
-  if (vm->stackSize >= STACK_MAX) {
-    fprintf(stderr, "ERROR: push(): refusing to overflow the stack!\n");
-    return;
-  }
-  vm->stack[vm->stackSize++] = value;
-}
-
-struct garbageObject *pop(struct virtualMachine *vm) {
-  if (vm->stackSize < 0) {
-    fprintf(stderr, "ERROR: pop(): Stack size cannot be negative!");
-    return NULL;
-  }
-
-  return vm->stack[--vm->stackSize];
-}
-
-struct garbageObject *initGarbage(struct virtualMachine *vm,
-                                  enum garbageData type) {
-
-  if (vm->refCount >= vm->refMax) {
-    collect(vm);
-  }
-
-  struct garbageObject *obj = malloc(sizeof(struct garbageObject));
-  if (obj == NULL) {
-    fprintf(stderr, "initGarbage(): Allocation failure!");
-    return obj;
-  }
-
-  obj->type = type;
-  obj->mark = 0;
-  obj->next = vm->head;
-  vm->head = obj;
-  vm->refCount++;
-  return obj;
-}
-
-void pushInt(struct virtualMachine *vm, int value) {
-  struct garbageObject *obj = initGarbage(vm, GARBAGE_INT);
-  if (obj == NULL) {
-    fprintf(stderr, "pushInt(): Unable to create GARBAGE_INT - out of memory?");
-  }
-
-  obj->value = value;
-  push(vm, obj);
-}
-
-struct garbageObject *pushPair(struct virtualMachine *vm) {
-  struct garbageObject *obj = initGarbage(vm, GARBAGE_PAIR);
-  if (obj == NULL) {
-    fprintf(stderr,
-            "pushPair(): Unable to create GARBAGE_PAIR - out of memory?");
-  }
-
-  obj->tail = pop(vm);
-  obj->head = pop(vm);
-
-  push(vm, obj);
-  return obj;
-}