shrink sha hashing a bit more (remove wbuflen field from ctx),

remove the requirement for aligned buffer

function                                             old     new   delta
sha512_hash                                          262     297     +35
sha1_end                                             136     143      +7
passwd_main                                         1019    1023      +4
sha256_end                                           135     137      +2
count_lines                                           72      74      +2
sha256_hash                                          259     260      +1
popstring                                            164     158      -6
sha512_begin                                          88      81      -7
sha256_begin                                          44      37      -7
parse_expr                                           832     824      -8
bbunpack                                             446     438      -8
sha256_process_block64                               529     520      -9
md5_end                                              166     151     -15
evaltreenr                                           817     802     -15
evaltree                                             817     802     -15
sha512_end                                           204     182     -22
sha512_process_block128                             1444    1405     -39
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 6/11 up/down: 51/-151)         Total: -100 bytes

1 files changed, 9 insertions, 10 deletions

diff --git a/libbb/md5.c b/libbb/md5.c
index eb15d758d..768dfbcb7 100644
--- a/libbb/md5.c
+++ b/libbb/md5.c
@@ -416,15 +416,14 @@ void FAST_FUNC md5_end(void *resbuf, md5_ctx_t *ctx)
 		md5_hash_block(ctx->buffer, ctx);
 	md5_hash_block(buf, ctx);
 
-	/* Put result from CTX in first 16 bytes following RESBUF.  The result is
-	 * always in little endian byte order, so that a byte-wise output yields
-	 * to the wanted ASCII representation of the message digest.
-	 *
-	 * IMPORTANT: On some systems it is required that RESBUF is correctly
-	 * aligned for a 32 bits value.
+	/* The MD5 result is in little endian byte order.
+	 * We (ab)use the fact that A-D are consecutive in memory.
 	 */
-	((uint32_t *) resbuf)[0] = SWAP_LE32(ctx->A);
-	((uint32_t *) resbuf)[1] = SWAP_LE32(ctx->B);
-	((uint32_t *) resbuf)[2] = SWAP_LE32(ctx->C);
-	((uint32_t *) resbuf)[3] = SWAP_LE32(ctx->D);
+#if BB_BIG_ENDIAN
+	ctx->A = SWAP_LE32(ctx->A);
+	ctx->B = SWAP_LE32(ctx->B);
+	ctx->C = SWAP_LE32(ctx->C);
+	ctx->D = SWAP_LE32(ctx->D);
+#endif
+	memcpy(resbuf, &ctx->A, sizeof(ctx->A) * 4);
 }