Bug 692367: NULL out pointers for three tables in the context

Add "finalize" methods for gs_name_table, io_device_table and
font_dir tables which ensure that the pointers in the lib
context are set to NULL when the memory is released.

No cluster differences.

5 files changed, 61 insertions, 7 deletions

diff --git a/gs/base/gsfont.c b/gs/base/gsfont.c
index ece4c9b2b..9535666bf 100644
--- a/gs/base/gsfont.c
+++ b/gs/base/gsfont.c
@@ -270,6 +270,15 @@ gs_font_dir_alloc2_limits(gs_memory_t * struct_mem, gs_memory_t * bits_mem,
     pdir->hash = 42;  /* initialize the hash to a randomly picked number */
     return pdir;
 }
+static void
+gs_font_dir_finalize(void *vptr)
+{
+    gs_font_dir *pdir = vptr;
+    if (pdir == pdir->memory->gs_lib_ctx->font_dir) {
+        pdir->memory->gs_lib_ctx->font_dir = NULL;
+    }
+}
+
 
 /* Allocate and minimally initialize a font. */
 gs_font *
diff --git a/gs/base/gsiodev.c b/gs/base/gsiodev.c
index 65b279d05..9b6f0e408 100644
--- a/gs/base/gsiodev.c
+++ b/gs/base/gsiodev.c
@@ -31,9 +31,9 @@ extern_gx_io_device_table();
 private_st_io_device();
 gs_private_st_ptr(st_io_device_ptr, gx_io_device *, "gx_io_device *",
                   iodev_ptr_enum_ptrs, iodev_ptr_reloc_ptrs);
-gs_private_st_element(st_io_device_ptr_element, gx_io_device *,
+gs_private_st_element_final(st_io_device_ptr_element, gx_io_device *,
       "gx_io_device *[]", iodev_ptr_elt_enum_ptrs, iodev_ptr_elt_reloc_ptrs,
-                      st_io_device_ptr);
+                      st_io_device_ptr,gs_iodev_finalize);
 
 /* Define the OS (%os%) device. */
 iodev_proc_fopen(iodev_os_fopen);
@@ -61,7 +61,7 @@ int
 gs_iodev_init(gs_memory_t * mem)
 {				/* Make writable copies of all IODevices. */
     gx_io_device **table =
-        gs_alloc_struct_array(mem, gx_io_device_table_count,
+        gs_alloc_struct_array(mem, gx_io_device_table_count + 1,
                               gx_io_device *, &st_io_device_ptr_element,
                               "gs_iodev_init(table)");
     gs_lib_ctx_t *libctx = gs_lib_ctx_get_interp_instance(mem);
@@ -80,6 +80,14 @@ gs_iodev_init(gs_memory_t * mem)
         table[i] = iodev;
         memcpy(table[i], gx_io_device_table[i], sizeof(gx_io_device));
     }
+    /* FIXME: we allocate an extra pointer in the array and stuff
+     * the memory context in there, as we need access to it in the
+     * finalize method below. We get away it because everywhere that
+     * searches the table uses gx_io_device_table_count, rather than
+     * the actuall allocated length.
+     * A less naff solution would be preferable!
+     */
+    table[gx_io_device_table_count] = (gx_io_device *) mem;
     libctx->io_device_table = table;
     code = gs_register_struct_root(mem, NULL,
                                    (void **)&libctx->io_device_table,
@@ -102,6 +110,16 @@ gs_iodev_init(gs_memory_t * mem)
     return (code < 0 ? code : gs_note_error(gs_error_VMerror));
 }
 
+static void
+gs_iodev_finalize(void *vptr)
+{
+    gx_io_device **table = vptr;
+    gs_memory_t * mem = ((gs_memory_t *)table[gx_io_device_table_count]);
+
+    mem->gs_lib_ctx->io_device_table = NULL;
+}
+
+
 /* ------ Default (unimplemented) IODevice procedures ------ */
 
 int
diff --git a/gs/base/gsstruct.h b/gs/base/gsstruct.h
index cd33da11a..bdfc3ff64 100644
--- a/gs/base/gsstruct.h
+++ b/gs/base/gsstruct.h
@@ -620,6 +620,24 @@ extern void reloc_const_bytestring(gs_const_bytestring *pbs, gc_state_t *gcst);
 #define gs_private_st_element(stname, stype, sname, penum, preloc, basest)\
   gs__st_element(private_st, stname, stype, sname, penum, preloc, basest)
 
+#define gs__st_element_final(scope_st, stname, stype, sname, penum, preloc, basest, pfinal)\
+  static ENUM_PTRS_BEGIN_PROC(penum) {\
+    uint count = size / (uint)sizeof(stype);\
+    if ( count == 0 ) return 0;\
+    return ENUM_USING(basest, (EV_CONST char *)vptr + (index % count) * sizeof(stype),\
+      sizeof(stype), index / count);\
+  } ENUM_PTRS_END_PROC\
+  static RELOC_PTRS_BEGIN(preloc) {\
+    uint count = size / (uint)sizeof(stype);\
+    for ( ; count; count--, vptr = (char *)vptr + sizeof(stype) )\
+      RELOC_USING(basest, vptr, sizeof(stype));\
+  } RELOC_PTRS_END\
+  gs__st_composite_final(scope_st, stname, stype, sname, penum, preloc,pfinal)
+#define gs_public_st_element_final(stname, stype, sname, penum, preloc, basest,pfinal)\
+  gs__st_element_final(public_st, stname, stype, sname, penum, preloc, basest,pfinal)
+#define gs_private_st_element_final(stname, stype, sname, penum, preloc, basest,pfinal)\
+  gs__st_element_final(private_st, stname, stype, sname, penum, preloc, basest,pfinal)
+
         /* A "structure" just consisting of a pointer. */
         /* Note that in this case only, stype is a pointer type. */
         /* Fortunately, C's bizarre 'const' syntax does what we want here. */
diff --git a/gs/base/gxfcache.h b/gs/base/gxfcache.h
index 3f3b5a73c..f6b97360e 100644
--- a/gs/base/gxfcache.h
+++ b/gs/base/gxfcache.h
@@ -319,8 +319,8 @@ struct gs_font_dir_s {
 };
 
 #define private_st_font_dir()	/* in gsfont.c */\
-  gs_private_st_composite(st_font_dir, gs_font_dir, "gs_font_dir",\
-    font_dir_enum_ptrs, font_dir_reloc_ptrs)
+  gs_private_st_composite_final(st_font_dir, gs_font_dir, "gs_font_dir",\
+    font_dir_enum_ptrs, font_dir_reloc_ptrs, gs_font_dir_finalize)
 
 /* Enumerate the pointers in a font directory, except for orig_fonts. */
 #define font_dir_do_ptrs(m)\
diff --git a/gs/psi/iname.c b/gs/psi/iname.c
index 96a6e8d8a..2d4764e18 100644
--- a/gs/psi/iname.c
+++ b/gs/psi/iname.c
@@ -37,13 +37,15 @@ static const byte nt_1char_names[NT_1CHAR_SIZE] = {
     NT_1CHAR_NAMES_DATA
 };
 
+static void gs_names_finalize(void *);
+
 /* Structure descriptors */
 gs_private_st_simple(st_name_sub_table, name_sub_table, "name_sub_table");
 gs_private_st_composite(st_name_string_sub_table, name_string_sub_table_t,
                         "name_string_sub_table_t",
                         name_string_sub_enum_ptrs, name_string_sub_reloc_ptrs);
-gs_private_st_composite(st_name_table, name_table, "name_table",
-                        name_table_enum_ptrs, name_table_reloc_ptrs);
+gs_private_st_composite_final(st_name_table, name_table, "name_table",
+                        name_table_enum_ptrs, name_table_reloc_ptrs,gs_names_finalize);
 
 /* Forward references */
 static int name_alloc_sub(name_table *);
@@ -127,6 +129,13 @@ names_init(ulong count, gs_ref_memory_t *imem)
     return nt;
 }
 
+static void
+gs_names_finalize(void *vptr)
+{
+    name_table *nt = vptr;
+    nt->memory->gs_lib_ctx->gs_name_table = NULL;
+}
+
 /* Get the allocator for the name table. */
 gs_memory_t *
 names_memory(const name_table * nt)