Sanitize the VFIL_searchpath() caling convention to not need throwing

away const.

bin/varnishd/mgt/mgt_vcl.c

@@ -282,12 +282,13 @@ mcf_vcl_load(struct cli *cli, const char * const *av, void *priv)
 	}
 
 	VFIL_setpath(&vcl_path, mgt_vcl_dir);
-	fn = TRUST_ME(av[3]);
-	if (VFIL_searchpath(vcl_path, NULL, &vcl, &fn)) {
+	if (VFIL_searchpath(vcl_path, NULL, &vcl, av[3], &fn)) {
 		VCLI_Out(cli, "Cannot open '%s'", fn != NULL ? fn : av[3]);
+		REPLACE(fn, NULL);
 		VCLI_SetResult(cli, CLIS_PARAM);
 		return;
 	}
+	REPLACE(fn, NULL);
 
 	mgt_new_vcl(cli, av[2], vcl, av[4], 0);
 	free(vcl);

include/vfil.h

@@ -39,5 +39,5 @@ int VFIL_allocate(int fd, off_t size, int insist);
 void VFIL_setpath(struct vfil_path**, const char *path);
 typedef int vfil_path_func_f(void *priv, const char *fn);
 int VFIL_searchpath(const struct vfil_path *, vfil_path_func_f *func,
-    void *priv, char **fn);
+    void *priv, const char *fni, char **fno);
 

lib/libvarnish/vfil.c

@@ -298,41 +298,38 @@ vfil_path_openfile(void *priv, const char *fn)
 
 int
 VFIL_searchpath(const struct vfil_path *vp, vfil_path_func_f *func, void *priv,
-    char **fnp)
+    const char *fni, char **fno)
 {
 	struct vsb *vsb;
 	struct vfil_dir *vd;
-	const char *fn;
 	int i, e;
 
 	CHECK_OBJ_NOTNULL(vp, VFIL_PATH_MAGIC);
-	AN(fnp);
-	AN(*fnp);
-	fn = *fnp;
-	*fnp = NULL;
+	AN(fno);
+	*fno = NULL;
 
 	if (func == NULL) {
 		func = vfil_path_openfile;
 		AN(priv);
 	}
 
-	if (*fn == '/') {
-		i = func(priv, fn);
+	if (*fni == '/') {
+		i = func(priv, fni);
 		if (i <= 0)
-			REPLACE(*fnp, fn);
+			REPLACE(*fno, fni);
 		return (i);
 	}
 	vsb = VSB_new_auto();
 	AN(vsb);
 	VTAILQ_FOREACH(vd, &vp->paths, list) {
 		VSB_clear(vsb);
-		VSB_printf(vsb, "%s/%s", vd->dir, fn);
+		VSB_printf(vsb, "%s/%s", vd->dir, fni);
 		AZ(VSB_finish(vsb));
 		i = func(priv, VSB_data(vsb));
 		if (i <= 0) {
 			e = errno;
-			*fnp = strdup(VSB_data(vsb));
-			AN(*fnp);
+			*fno = strdup(VSB_data(vsb));
+			AN(*fno);
 			VSB_delete(vsb);
 			errno = e;
 			return (i);

lib/libvcc/vcc_compile.c

@@ -450,7 +450,7 @@ vcc_destroy_source(struct source *sp)
 /*--------------------------------------------------------------------*/
 
 static struct source *
-vcc_file_source(const struct vcp * const vcp, struct vsb *sb, char *fn)
+vcc_file_source(const struct vcp * const vcp, struct vsb *sb, const char *fn)
 {
 	char *f, *fnp;
 	struct source *sp;
@@ -460,8 +460,7 @@ vcc_file_source(const struct vcp * const vcp, struct vsb *sb, char *fn)
 		return (NULL);
 	}
 	f = NULL;
-	fnp = fn;
-	if (VFIL_searchpath(vcp->vcl_path, NULL, &f, &fnp) || f == NULL) {
+	if (VFIL_searchpath(vcp->vcl_path, NULL, &f, fn, &fnp) || f == NULL) {
 		VSB_printf(sb, "Cannot read file '%s' (%s)\n",
 		    fnp != NULL ? fnp : fn, strerror(errno));
 		return (NULL);

lib/libvcc/vcc_vmod.c

@@ -49,7 +49,6 @@ vcc_path_dlopen(void *priv, const char *fn)
 	AN(priv);
 	AN(fn);
 
-fprintf(stderr, "TRY <%s>\n", fn);
 	hdl = dlopen(fn, RTLD_NOW | RTLD_LOCAL);
 	if (hdl == NULL)
 		return (1);
@@ -126,9 +125,8 @@ vcc_ParseImport(struct vcc *tl)
 
 	SkipToken(tl, ';');
 
-	fnp = fn;
 	if (VFIL_searchpath(tl->param->vmod_path,
-	    vcc_path_dlopen, &hdl, &fnp)) {
+	    vcc_path_dlopen, &hdl, fn, &fnp)) {
 		VSB_printf(tl->sb, "Could not load VMOD %.*s\n", PF(mod));
 		VSB_printf(tl->sb, "\tFile name: %s\n", fnp != NULL ? fnp : fn);
 		VSB_printf(tl->sb, "\tdlerror: %s\n", dlerror());