[PATCH 05/15] Fix C++ includability of crypto headers with static array sizes

[Sebastian Huber]

From: Alan Somers <asomers at FreeBSD.org>

C99 allows array function parameters to use the static keyword for their
sizes. This tells the compiler that the parameter will have at least the
specified size, and calling code will fail to compile if that guarantee is
not met. However, this syntax is not legal in C++.

This commit reverts r300824, which worked around the problem for
sys/sys/md5.h only, and introduces a new macro: min_size(). min_size(x) can
be used in headers as a static array size, but will still compile in C++
mode.

Reviewed by:	cem, ed
MFC after:	4 weeks
Sponsored by:	Spectra Logic Corp
Differential Revision:	https://reviews.freebsd.org/D8277
---
 cpukit/include/sha256.h  | 3 ++-
 cpukit/include/sha384.h  | 3 ++-
 cpukit/include/sha512.h  | 3 ++-
 cpukit/include/sha512t.h | 6 ++++--
 4 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/cpukit/include/sha256.h b/cpukit/include/sha256.h
index 4fe35935c0..f612713f3d 100644
--- a/cpukit/include/sha256.h
+++ b/cpukit/include/sha256.h
@@ -47,7 +47,8 @@ __BEGIN_DECLS
 
 void	SHA256_Init(SHA256_CTX *);
 void	SHA256_Update(SHA256_CTX *, const void *, size_t);
-void	SHA256_Final(unsigned char [static SHA256_DIGEST_LENGTH], SHA256_CTX *);
+void	SHA256_Final(unsigned char [__min_size(SHA256_DIGEST_LENGTH)],
+    SHA256_CTX *);
 #ifndef _KERNEL
 char   *SHA256_End(SHA256_CTX *, char *);
 char   *SHA256_Data(const void *, unsigned int, char *);
diff --git a/cpukit/include/sha384.h b/cpukit/include/sha384.h
index 52f69efc95..4306d4195b 100644
--- a/cpukit/include/sha384.h
+++ b/cpukit/include/sha384.h
@@ -47,7 +47,8 @@ __BEGIN_DECLS
 
 void	SHA384_Init(SHA384_CTX *);
 void	SHA384_Update(SHA384_CTX *, const void *, size_t);
-void	SHA384_Final(unsigned char [static SHA384_DIGEST_LENGTH], SHA384_CTX *);
+void	SHA384_Final(unsigned char [__min_size(SHA384_DIGEST_LENGTH)],
+    SHA384_CTX *);
 #ifndef _KERNEL
 char   *SHA384_End(SHA384_CTX *, char *);
 char   *SHA384_Data(const void *, unsigned int, char *);
diff --git a/cpukit/include/sha512.h b/cpukit/include/sha512.h
index de7d19abb3..89fbe0516e 100644
--- a/cpukit/include/sha512.h
+++ b/cpukit/include/sha512.h
@@ -47,7 +47,8 @@ __BEGIN_DECLS
 
 void	SHA512_Init(SHA512_CTX *);
 void	SHA512_Update(SHA512_CTX *, const void *, size_t);
-void	SHA512_Final(unsigned char [static SHA512_DIGEST_LENGTH], SHA512_CTX *);
+void	SHA512_Final(unsigned char [__min_size(SHA512_DIGEST_LENGTH)],
+    SHA512_CTX *);
 #ifndef _KERNEL
 char   *SHA512_End(SHA512_CTX *, char *);
 char   *SHA512_Data(const void *, unsigned int, char *);
diff --git a/cpukit/include/sha512t.h b/cpukit/include/sha512t.h
index 20f206f141..f48606a393 100644
--- a/cpukit/include/sha512t.h
+++ b/cpukit/include/sha512t.h
@@ -44,7 +44,8 @@ __BEGIN_DECLS
 
 void	SHA512_224_Init(SHA512_CTX *);
 void	SHA512_224_Update(SHA512_CTX *, const void *, size_t);
-void	SHA512_224_Final(unsigned char [static SHA512_224_DIGEST_LENGTH], SHA512_CTX *);
+void	SHA512_224_Final(unsigned char [__min_size(SHA512_224_DIGEST_LENGTH)],
+    SHA512_CTX *);
 #ifndef _KERNEL
 char   *SHA512_224_End(SHA512_CTX *, char *);
 char   *SHA512_224_Data(const void *, unsigned int, char *);
@@ -53,7 +54,8 @@ char   *SHA512_224_FileChunk(const char *, char *, off_t, off_t);
 #endif
 void	SHA512_256_Init(SHA512_CTX *);
 void	SHA512_256_Update(SHA512_CTX *, const void *, size_t);
-void	SHA512_256_Final(unsigned char [static SHA512_256_DIGEST_LENGTH], SHA512_CTX *);
+void	SHA512_256_Final(unsigned char [__min_size(SHA512_256_DIGEST_LENGTH)],
+    SHA512_CTX *);
 #ifndef _KERNEL
 char   *SHA512_256_End(SHA512_CTX *, char *);
 char   *SHA512_256_Data(const void *, unsigned int, char *);
-- 
2.35.3