libctf, types: enhance ctf_type_aname to print function arg types

Somehow this never got implemented, which makes debugging any kind of
bug that has to do with argument types fantastically confusing, because
it *looks* like the func type takes no arguments though in fact it does.

This also lets us simplify the dumper slightly (and introduces our first
uses of ctf_assert and ctf_err_warn: there will be many more).

ctf_type_aname dumps function types without including the function
pointer name itself: ctf_dump search-and-replaces it in.  This seems to
give the nicest-looking results for existing users of both, even if it
is a bit fiddly.

libctf/
	* ctf-types.c (ctf_type_aname): Print arg types here...
	* ctf-dump.c (ctf_dump_funcs): ... not here: but do substitute
	in the type name here.

1 files changed, 45 insertions, 1 deletions

diff --git a/libctf/ctf-types.c b/libctf/ctf-types.c
index 5500682..ddcca66 100644
--- a/libctf/ctf-types.c
+++ b/libctf/ctf-types.c
@@ -745,7 +745,51 @@ ctf_type_aname (ctf_file_t *fp, ctf_id_t type)
 	      ctf_decl_sprintf (&cd, "[%u]", cdp->cd_n);
 	      break;
 	    case CTF_K_FUNCTION:
-	      ctf_decl_sprintf (&cd, "()");
+	      {
+		size_t i;
+		ctf_funcinfo_t fi;
+		ctf_id_t *argv = NULL;
+
+		if (ctf_func_type_info (rfp, cdp->cd_type, &fi) < 0)
+		  goto err;		/* errno is set for us.  */
+
+		if ((argv = calloc (fi.ctc_argc, sizeof (ctf_id_t *))) == NULL)
+		  {
+		    ctf_set_errno (rfp, errno);
+		    goto err;
+		  }
+
+		if (ctf_func_type_args (rfp, cdp->cd_type,
+					fi.ctc_argc, argv) < 0)
+		  goto err;		/* errno is set for us.  */
+
+		ctf_decl_sprintf (&cd, "(*) (");
+		for (i = 0; i < fi.ctc_argc; i++)
+		  {
+		    char *arg = ctf_type_aname (rfp, argv[i]);
+
+		    if (arg == NULL)
+		      goto err;		/* errno is set for us.  */
+		    ctf_decl_sprintf (&cd, "%s", arg);
+		    free (arg);
+
+		    if ((i < fi.ctc_argc - 1)
+			|| (fi.ctc_flags & CTF_FUNC_VARARG))
+		      ctf_decl_sprintf (&cd, ", ");
+		  }
+
+		if (fi.ctc_flags & CTF_FUNC_VARARG)
+		  ctf_decl_sprintf (&cd, "...");
+		ctf_decl_sprintf (&cd, ")");
+
+		free (argv);
+		break;
+
+	      err:
+		free (argv);
+		ctf_decl_fini (&cd);
+		return NULL;
+	      }
 	      break;
 	    case CTF_K_STRUCT:
 	    case CTF_K_FORWARD: