From: Todd C. Miller <Todd.Miller@courtesan.com>
Date: Tue, 5 Mar 2013 15:18:32 +0000 (-0500)
Subject: Add __malloc_like macro to apply __malloc__ attribute to emalloc,
X-Git-Tag: SUDO_1_8_7~1^2~188
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4e5baccb9c98b602aecc9f659bdd5b1527bf6a88;p=sudo

Add __malloc_like macro to apply __malloc__ attribute to emalloc,
ecalloc and estrdup.  It cannot be applied to realloc since that
may return the same pointer.
---

diff --git a/include/alloc.h b/include/alloc.h
index b5b3e381d..77ba2a289 100644
--- a/include/alloc.h
+++ b/include/alloc.h
@@ -22,13 +22,13 @@
 int	 easprintf(char **, const char *, ...) __printflike(2, 3);
 int	 evasprintf(char **, const char *, va_list) __printflike(2, 0);
 void	 efree(void *);
-void	*ecalloc(size_t, size_t);
-void	*emalloc(size_t);
-void	*emalloc2(size_t, size_t);
+void	*ecalloc(size_t, size_t) __malloc_like;
+void	*emalloc(size_t) __malloc_like;
+void	*emalloc2(size_t, size_t) __malloc_like;
 void	*erealloc(void *, size_t);
 void	*erealloc3(void *, size_t, size_t);
 void	*erecalloc(void *, size_t, size_t, size_t);
-char	*estrdup(const char *);
-char	*estrndup(const char *, size_t);
+char	*estrdup(const char *) __malloc_like;
+char	*estrndup(const char *, size_t) __malloc_like;
 
 #endif /* _SUDO_ALLOC_H */
diff --git a/include/missing.h b/include/missing.h
index 8276065cf..ddb6a05e5 100644
--- a/include/missing.h
+++ b/include/missing.h
@@ -52,6 +52,15 @@
 # endif
 #endif
 
+/* Hint to compiler that returned pointer is unique (malloc but not realloc). */
+#ifndef __malloc_like
+# if __GNUC_PREREQ__(2, 96)
+#  define __malloc_like 	__attribute__((__malloc__))
+# else
+#  define __malloc_like
+# endif
+#endif
+
 #ifndef __dso_public
 # ifdef HAVE_DSO_VISIBILITY
 #  if defined(__GNUC__)