From c6670b46c342227c0c9f44bc96dd0e283670f06a Mon Sep 17 00:00:00 2001
From: "Jan (janneke) Nieuwenhuizen" <janneke@gnu.org>
Date: Mon, 22 Jun 2020 18:00:15 +0200
Subject: [PATCH] core: gc: Fixes.

* src/gc.c (gc_init, gc_up_arena, gc_flip): Change to void function.
Fixes 0 returns.
(make_bytes): Use plain.
(make_string): Add 1 to length, for zero-terminated C strings.
(gc_copy): Use plain bytes length.
(gc_loop): Manually reformat.
---
 include/mes/mes.h |  3 ++-
 src/gc.c          | 66 +++++++++++++++++++++++++++++------------------
 2 files changed, 43 insertions(+), 26 deletions(-)

diff --git a/include/mes/mes.h b/include/mes/mes.h
index a6b555e7..1e94def9 100644
--- a/include/mes/mes.h
+++ b/include/mes/mes.h
@@ -81,7 +81,6 @@ SCM builtin_name (SCM builtin);
 SCM cstring_to_list (char const *s);
 SCM cstring_to_symbol (char const *s);
 SCM fdisplay_ (SCM, int, int);
-SCM gc_init ();
 SCM gc_peek_frame ();
 SCM gc_pop_frame ();
 SCM gc_push_frame ();
@@ -118,6 +117,8 @@ long length__ (SCM x);
 size_t bytes_cells (size_t length);
 void assert_max_string (size_t i, char const *msg, char *string);
 void assert_msg (int check, char *msg);
+void gc_ ();
+void gc_init ();
 
 #include "mes/builtins.h"
 #include "mes/constants.h"
diff --git a/src/gc.c b/src/gc.c
index da7fc219..4bac1513 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -37,8 +37,8 @@ news_bytes (SCM x)
   return &NCDR (x);
 }
 
-SCM
-gc_init ()                      /*:((internal)) */
+void
+gc_init ()
 {
 #if SYSTEM_LIBC
   ARENA_SIZE = 100000000;       /* 2.3GiB */
@@ -82,8 +82,6 @@ gc_init ()                      /*:((internal)) */
 
   /* FIXME: remove MES_MAX_STRING, grow dynamically */
   g_buf = malloc (MAX_STRING);
-
-  return 0;
 }
 
 SCM
@@ -131,7 +129,7 @@ cons (SCM x, SCM y)
 size_t
 bytes_cells (size_t length)
 {
-  return (1 + sizeof (long) + sizeof (long) + length + sizeof (SCM)) / sizeof (SCM);
+  return (sizeof (long) + sizeof (long) + length - 1 + sizeof (SCM)) / sizeof (SCM);
 }
 
 SCM
@@ -150,7 +148,7 @@ make_bytes (char const *s, size_t length)
   if (length == 0)
     p[0] = 0;
   else
-    memcpy (p, s, length + 1);
+    memcpy (p, s, length);
 
   return x;
 }
@@ -191,7 +189,7 @@ make_string (char const *s, size_t length)
   if (length > MAX_STRING)
     assert_max_string (length, "make_string", s);
   SCM x = make_cell (TSTRING, length, 0);
-  SCM v = make_bytes (s, length);
+  SCM v = make_bytes (s, length + 1);
   CDR (x) = v;
   return x;
 }
@@ -208,8 +206,8 @@ make_string_port (SCM x)        /*:((internal)) */
   return make_cell (TPORT, -length__ (g_ports) - 2, x);
 }
 
-SCM
-gc_up_arena ()                  /*:((internal)) */
+void
+gc_up_arena ()
 {
   long old_arena_bytes = (ARENA_SIZE + JAM_SIZE) * sizeof (struct scm);
   if (ARENA_SIZE >> 1 < MAX_ARENA_SIZE >> 2)
@@ -235,12 +233,10 @@ gc_up_arena ()                  /*:((internal)) */
   g_cells = p;
   memcpy (p + arena_bytes, p + old_arena_bytes, STACK_SIZE * sizeof (SCM));
   g_cells = g_cells + 1;
-
-  return 0;
 }
 
 void
-gc_flip ()                      /*:((internal)) */
+gc_flip ()
 {
   if (g_debug > 2)
     {
@@ -276,7 +272,7 @@ gc_copy (SCM old)               /*:((internal)) */
       char const *src = cell_bytes (old);
       char *dest = news_bytes (new);
       size_t length = NLENGTH (new);
-      memcpy (dest, src, length + 1);
+      memcpy (dest, src, length);
       g_free = g_free + bytes_cells (length) - 1;
 
       if (g_debug > 4)
@@ -321,24 +317,43 @@ gc_loop (SCM scan)              /*:((internal)) */
   SCM cdr;
   while (scan < g_free)
     {
-      if (NTYPE (scan) == TBROKEN_HEART)
-        error (cell_symbol_system_error, cstring_to_symbol ("gc"));
-      if (NTYPE (scan) == TMACRO || NTYPE (scan) == TPAIR || NTYPE (scan) == TREF || scan == 1  /* null */
-          || NTYPE (scan) == TVARIABLE)
+      long t = NTYPE (scan);
+      if (t == TBROKEN_HEART)
+        assert_msg (0, "broken heart");
+      /* *INDENT-OFF* */
+      if (t == TMACRO
+          || t == TPAIR
+          || t == TREF
+          || t == TVARIABLE)
+        /* *INDENT-ON* */
         {
           car = gc_copy (NCAR (scan));
           gc_relocate_car (scan, car);
         }
-      if ((NTYPE (scan) == TCLOSURE || NTYPE (scan) == TCONTINUATION || NTYPE (scan) == TKEYWORD || NTYPE (scan) == TMACRO || NTYPE (scan) == TPAIR || NTYPE (scan) == TPORT || NTYPE (scan) == TSPECIAL || NTYPE (scan) == TSTRING || NTYPE (scan) == TSYMBOL || scan == 1     /* null */
-           || NTYPE (scan) == TVALUES)
-          && NCDR (scan))   /* allow for 0 terminated list of symbols */
+      /* *INDENT-OFF* */
+      if ((t == TCLOSURE
+           || t == TCONTINUATION
+           || t == TKEYWORD
+           || t == TMACRO
+           || t == TPAIR
+           || t == TPORT
+           || t == TSPECIAL
+           || t == TSTRING
+           /*|| t == TSTRUCT handled by gc_copy */
+           || t == TSYMBOL
+           || t == TVALUES
+           /*|| t == TVECTOR handled by gc_copy */
+           )
+          && NCDR (scan))   /* Allow for 0 terminated list of symbols. */
+        /* *INDENT-ON* */
         {
           cdr = gc_copy (NCDR (scan));
           gc_relocate_cdr (scan, cdr);
         }
-      if (NTYPE (scan) == TBYTES)
-        scan = scan + bytes_cells (NLENGTH (scan)) - 1;
-      scan = scan + 1;
+      if (t == TBYTES)
+        scan = scan + bytes_cells (NLENGTH (scan));
+      else
+        scan = scan + 1;
     }
   gc_flip ();
 }
@@ -351,8 +366,8 @@ gc_check ()
   return cell_unspecified;
 }
 
-SCM
-gc_ ()                          /*:((internal)) */
+void
+gc_ ()
 {
   gc_init_news ();
   if (g_debug == 2)
@@ -422,6 +437,7 @@ gc ()
       write_error_ (R0);
       eputs ("\n");
     }
+  return cell_unspecified;
 }
 
 SCM