a more complete testcase

tester.mk (text/plain), 1.37 KB, created by Malte S. Stretz on 2005-01-21 14:00:09 UTC

MAKEFILE=tester.mk
LIB=libtester_
APP=tester_

test: $(LIB).so $(APP)
	LD_PRELOAD="./libtester_.so:/lib/libdl.so.2" ./tester_

clean:
	rm -f $(LIB).so $(LIB).c
	rm -f $(APP) $(APP).c

%.c: $(MAKEFILE)
	sed -ne '/^$@.in/,/^[^\t]/{s/^\(\t\|[^\t].*\)//;p}' $< > $@

$(APP): $(APP).c
	cc -fstack-protector $< -o $@

$(LIB).so: $(LIB).c
	cc -fstack-protector -rdynamic $< -o $@ -shared


libtester_.c.in:
	#define _GNU_SOURCE 1
	#include <stdlib.h>
	#include <stdio.h>
	#include <stdarg.h>
	#include <string.h>
	#include <dlfcn.h>
	typedef ssize_t (*orig_read_ptr)(int fd, void *buf, size_t count);
	static orig_read_ptr orig_read;
	static int libtester_initialized = 0;
	static void libtester_init()
	{
	  if (libtester_initialized) return;
	  fprintf(stderr, "%s:%i\n", __FILE__, __LINE__);
	  orig_read  = (orig_read_ptr)dlsym(RTLD_NEXT, "read");
	  libtester_initialized = 1;
	  fprintf(stderr, "%s:%i\n", __FILE__, __LINE__);
	}
	ssize_t read (int fd, void *buf, size_t count)
	{
	  int r;
	  fprintf(stderr, "%s:%i\n", __FILE__, __LINE__);
	  libtester_init();
	  r = orig_read(fd, buf, count);
	  fprintf(stderr, "%s:%i\n", __FILE__, __LINE__);
	  return r;
	}

tester_.c.in:
	#include <stdio.h>
	#include <string.h>
	int main(int c, char **a) {
	  char buf[10];
	  printf("%s:%i\n", __FILE__, __LINE__);
	  memset(buf, 0, sizeof (buf) * 2);
	  printf("%s:%i\n", __FILE__, __LINE__);
	  return 0;
	}