linker: Make the errors reported by dlopen/dlsym be more useful.
Changed it so that when the linker generates error messages, they are
scribbled away into a buffer that dlfcn and friends can read from.
Since the error messages are generetad with snprintf, and snprintf
MAY call malloc during some code paths, we now link against a version
of libc that does not contain malloc/free/realloc/calloc. We then define
malloc and friends in the dynamic loader, and make them abort() if they
are ever called.
Signed-off-by: Dima Zavin <dima@android.com>
diff --git a/linker/linker_debug.h b/linker/linker_debug.h
index 3cc1343..3f4fc4c 100644
--- a/linker/linker_debug.h
+++ b/linker/linker_debug.h
@@ -55,17 +55,16 @@
#define TRUE 1
#define FALSE 0
-
-#define __PRINTVF(v,f,x...) do { \
- (debug_verbosity > (v)) && (printf(x), ((f) && fflush(stdout))); \
- } while (0)
/* Only use printf() during debugging. We have seen occasional memory
* corruption when the linker uses printf().
*/
#if LINKER_DEBUG
extern int debug_verbosity;
#warning "*** LINKER IS USING printf(); DO NOT CHECK THIS IN ***"
-#define _PRINTVF(v,f,x...) __PRINTVF(v,f,x)
+#define _PRINTVF(v,f,x...) \
+ do { \
+ (debug_verbosity > (v)) && (printf(x), ((f) && fflush(stdout))); \
+ } while (0)
#else /* !LINKER_DEBUG */
#define _PRINTVF(v,f,x...) do {} while(0)
#endif /* LINKER_DEBUG */
@@ -75,8 +74,9 @@
#define TRACE(x...) _PRINTVF(1, TRUE, x)
#define WARN(fmt,args...) \
_PRINTVF(-1, TRUE, "%s:%d| WARNING: " fmt, __FILE__, __LINE__, ## args)
-#define ERROR(fmt,args...) \
- __PRINTVF(-1, TRUE, "%s:%d| ERROR: " fmt, __FILE__, __LINE__, ## args)
+#define ERROR(fmt,args...) \
+ _PRINTVF(-1, TRUE, "%s:%d| ERROR: " fmt, __FILE__, __LINE__, ## args)
+
#if TRACE_DEBUG
#define DEBUG(x...) _PRINTVF(2, TRUE, "DEBUG: " x)