Stricter flexelinting

Until now, we used the lnt file from varnish-cache, which suppressed
some errors which are actually interesting for us (e.g. the wrong
VSPLAY_FOREACH() was spotted by flexelint with stricter rules).

src/flint.lnt

@@ -2,6 +2,8 @@
 -efile(451, tbl*)
 
 -ecall(835, dlopen)
+-e716	// while(1) ...
+-e717	// do ... while(0);
 -e801	// goto
 -ecall(840, VSB_bcat)
 -e793	// significant characters in an external identifier
@@ -19,9 +21,11 @@
 -efile(766, *_if.c)
 -esym(528, avoid_compiler_warnings)
 -esym(528, vmod_priv_blob*, VGC_*)
+-esym(728, vmod_priv_blob*, VGC_*)
 -esym(843, vmod_priv_blob*, VGC_*)
 -esym(844, vmod_priv_blob*, VGC_*)
 -esym(768, arg_vmod_blob*)
+-emacro(774, REPLACE)	// 'if' always evaluates to False
 
 // not fully understood
 -efunc(413, *_VSPLAY_NEXT)

src/tus_blob.c

@@ -127,8 +127,8 @@ tus_chksum_init(VRT_CTX) {
 		if (digest_ ## t == NULL)				\
 			break;						\
 		if (first == 0)						\
-			VSB_cat(names, ",");				\
-		VSB_cat(names, #t);					\
+			AZ(VSB_cat(names, ","));			\
+		AZ(VSB_cat(names, #t));					\
 		first = 0;						\
 	} while (0);
 #include "tbl_hash_enum.h"
@@ -223,7 +223,7 @@ tus_chksum_new(VRT_CTX, struct vmod_blobdigest_digest *d)
 
 	AN(d);
 
-	r = WS_Alloc(ctx->ws, sizeof *r);
+	r = WS_Alloc(ctx->ws, (unsigned)sizeof *r);
 	if (r == NULL) {
 		VRT_fail(ctx, "WS_Alloc failed");
 		return (NULL);
@@ -249,7 +249,8 @@ tus_chksum_hdr(VRT_CTX, const char *hdr)
 	if (sep == NULL)
 		return (NULL);
 
-	d = tus_hash(hdr, (unsigned)(sep - hdr));
+	assert(sep >= hdr);
+	d = tus_hash(hdr, (size_t)(sep - hdr));
 	if (d == NULL)
 		return (NULL);
 
@@ -259,7 +260,7 @@ tus_chksum_hdr(VRT_CTX, const char *hdr)
 
 	sep++;
 
-	expect = tus_b64_decode(ctx, sep, 0);
+	expect = tus_b64_decode(ctx, sep, (size_t)0);
 
 	if (expect == NULL)
 		return (NULL);
@@ -273,7 +274,7 @@ tus_chksum_update(VRT_CTX, const struct tus_chksum *c,
     const void *ptr, size_t l)
 {
 	struct vrt_blob b;
-	struct arg_vmod_blobdigest_digest_update a[1] = {{0}};
+	struct arg_vmod_blobdigest_digest_update a = {0};
 
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
 	CHECK_OBJ_NOTNULL(c, VMOD_TUS_CHKSUM_MAGIC);
@@ -283,10 +284,10 @@ tus_chksum_update(VRT_CTX, const struct tus_chksum *c,
 	b.len = l;
 	b.blob = ptr;
 
-	a->valid_msg = 1;
-	a->msg = &b;
+	a.valid_msg = 1;
+	a.msg = &b;
 
-	(void) vmod_blobdigest->f_digest_update(ctx, c->digest, a);
+	(void) vmod_blobdigest->f_digest_update(ctx, c->digest, &a);
 }
 
 VCL_BLOB

src/tus_file.h

@@ -40,8 +40,8 @@
  */
 extern struct VSC_lck *lck_fcore;
 
-#define TUS_PATH_MAX		PATH_MAX
-#define TUS_METADATA_MAX	2048u	// ballpark of AWS S3 metadata
+#define TUS_PATH_MAX		((size_t)PATH_MAX)
+#define TUS_METADATA_MAX	((size_t)2048)	// ballpark of AWS S3 metadata
 
 enum tus_f_type {
 	TUS_SINGLE = 0,