add optional macros to directly provide the <stdlib.h> interface

3 files changed, 35 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index b31f413..fb4d4b0 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,8 @@ TESTS=$(BINDIR)/overflow \
 	$(BINDIR)/zero \
 	$(BINDIR)/realloc \
 	$(BINDIR)/use-after-free \
-	$(BINDIR)/double-free
+	$(BINDIR)/double-free \
+	$(BINDIR)/macros
 
 all: $(LIBDIR)/libmapalloc.a $(LIBDIR)/libwrapalloc.so
 
@@ -50,6 +51,7 @@ $(BINDIR)/zero: $(TESTDIR)/zero.c
 $(BINDIR)/realloc: $(TESTDIR)/realloc.c
 $(BINDIR)/use-after-free: $(TESTDIR)/use-after-free.c
 $(BINDIR)/double-free: $(TESTDIR)/double-free.c
+$(BINDIR)/macros: $(TESTDIR)/macros.c
 
 $(BINDIR)/wrapper: $(TESTDIR)/wrapper.c
 	@mkdir -p $(@D)
diff --git a/include/mapalloc.h b/include/mapalloc.h
index 65581c8..1c43f2b 100644
--- a/include/mapalloc.h
+++ b/include/mapalloc.h
@@ -9,9 +9,16 @@ void *MA_realloc(void *ptr, size_t n);
 void MA_free(void *ptr);
 
 #ifdef MA_OVERRIDE_STDLIB
+#undef malloc
 #define malloc(n)	MA_malloc(n)
+
+#undef calloc
 #define calloc(n, e)	MA_calloc(n, e)
+
+#undef realloc
 #define realloc(p, n)	MA_realloc(p, n)
+
+#undef free
 #define free(p)		MA_free(p)
 #endif
 
diff --git a/test/macros.c b/test/macros.c
new file mode 100644
index 0000000..3c7a35a
--- /dev/null
+++ b/test/macros.c
@@ -0,0 +1,25 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#define MA_OVERRIDE_STDLIB
+#include "mapalloc.h"
+
+int main(void)
+{
+	const char buf[] = "THIS IS A CONSTANT STRING";
+
+	char *ptr = realloc(NULL, sizeof(buf));
+	memcpy(ptr, buf, sizeof(buf));
+	printf("%p: %s\n", ptr, ptr);
+
+	ptr = realloc(ptr, sizeof(buf) * 2);
+	memcpy(ptr + sizeof(buf) - 1, buf, sizeof(buf));
+	printf("%p: %s\n", ptr, ptr);
+
+	ptr = realloc(ptr, sizeof(buf) * sysconf(_SC_PAGESIZE));
+	memcpy(ptr + (2 * sizeof(buf)) - 2, buf, sizeof(buf));
+	printf("%p: %s\n", ptr, ptr);
+}