use library constructor to register print_status

1 files changed, 1 insertions, 59 deletions

diff --git a/print_status_on_exit.c b/print_status_on_exit.c
index 23df6bc..1d72384 100644
--- a/print_status_on_exit.c
+++ b/print_status_on_exit.c
@@ -4,17 +4,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-char tmpbuff[1024];
-unsigned long tmppos = 0;
-unsigned long tmpallocs = 0;
-
-/*=========================================================
- *  * interception points
- *  */
-
-static void * (*myfn_malloc)(size_t size);
-static void   (*myfn_free)(void *ptr);
-
 static void print_status(void)
 {
 	char buf[4096];
@@ -41,55 +30,8 @@ static void print_status(void)
 	fclose(status);
 }
 
-static void init()
+static void __attribute__((constructor)) init()
 {
-	myfn_malloc     = dlsym(RTLD_NEXT, "malloc");
-	myfn_free       = dlsym(RTLD_NEXT, "free");
-
-	if (!myfn_malloc || !myfn_free)
-	{
-		fprintf(stderr, "Error in `dlsym`: %s\n", dlerror());
-		exit(1);
-	}
 	atexit(print_status);
 }
 
-void *malloc(size_t size)
-{
-	static int initializing = 0;
-	if (myfn_malloc == NULL)
-	{
-		if (!initializing)
-		{
-			initializing = 1;
-			init();
-			initializing = 0;
-		}
-		else
-		{
-			if (tmppos + size < sizeof(tmpbuff))
-			{
-				void *retptr = tmpbuff + tmppos;
-				tmppos += size;
-				++tmpallocs;
-				return retptr;
-			}
-			else
-			{
-				fprintf(stderr, "jcheck: too much memory requested during initialisation - increase tmpbuff size\n");
-				exit(1);
-			}
-		}
-	}
-	return myfn_malloc(size);
-}
-
-void free(void *ptr)
-{
-	// something wrong if we call free before one of the allocators!
-	if (myfn_malloc == NULL)
-		init();
-	if (!(ptr >= (void*) tmpbuff && ptr <= (void*)(tmpbuff + tmppos)))
-		myfn_free(ptr);
-}
-