colour handling - ensure ink names are maintained in the name table while in use

Bug #692884 "Empty Spotcolor Name in generated PDF"

The ink name wasn't being marked as 'in use' by the colour space structure
and so was being freed by a garbage collection, resulting in an empty name.

Robin Watts supplied this patch which allows us to *much* more easily mark
names as in use, and also kindly updated the colour handling as well.

No differences expected.

6 files changed, 39 insertions, 2 deletions

diff --git a/gs/base/gscdevn.c b/gs/base/gscdevn.c
index 35f0f5f81..69a5ee1db 100644
--- a/gs/base/gscdevn.c
+++ b/gs/base/gscdevn.c
@@ -74,7 +74,14 @@ const gs_color_space_type gs_color_space_type_DeviceN = {
 /* GC procedures */
 
 static
-ENUM_PTRS_BEGIN(cs_DeviceN_enum_ptrs) return 0;
+ENUM_PTRS_BEGIN(cs_DeviceN_enum_ptrs)
+{
+    gs_device_n_params *params = &((gs_color_space *)vptr)->params.device_n;
+    if (index-3 < params->num_components)
+        return ENUM_NAME_INDEX(params->names[index-3]);
+    else
+        return 0;
+}
 ENUM_PTR(0, gs_color_space, params.device_n.names);
 ENUM_PTR(1, gs_color_space, params.device_n.map);
 ENUM_PTR(2, gs_color_space, params.device_n.colorants);
diff --git a/gs/base/gscsepr.c b/gs/base/gscsepr.c
index e521ea017..f377b225a 100644
--- a/gs/base/gscsepr.c
+++ b/gs/base/gscsepr.c
@@ -66,6 +66,7 @@ const gs_color_space_type gs_color_space_type_Separation = {
 static
 ENUM_PTRS_BEGIN(cs_Separation_enum_ptrs) return 0;
     ENUM_PTR(0, gs_color_space, params.separation.map);
+    case 1 : return ENUM_NAME_INDEX_ELT(gs_color_space, params.separation.sep_name);
 ENUM_PTRS_END
 static RELOC_PTRS_BEGIN(cs_Separation_reloc_ptrs)
 {
diff --git a/gs/base/gslib.c b/gs/base/gslib.c
index 5f2106b65..4a76692a4 100644
--- a/gs/base/gslib.c
+++ b/gs/base/gslib.c
@@ -265,6 +265,8 @@ void
 gs_reloc_const_string(gs_const_string * sptr, gc_state_t * gcst)
 {
 }
+const gs_ptr_procs_t ptr_name_index_procs =
+{NULL, NULL, NULL};
 
 /* Other stubs */
 static void
diff --git a/gs/base/gsstruct.h b/gs/base/gsstruct.h
index bdfc3ff64..aa3f57da4 100644
--- a/gs/base/gsstruct.h
+++ b/gs/base/gsstruct.h
@@ -126,6 +126,10 @@ extern const gs_ptr_procs_t ptr_string_procs;
 extern const gs_ptr_procs_t ptr_const_string_procs;
 #define ptr_const_string_type (&ptr_const_string_procs)
 
+/* Define the pointer type for name indexes. */
+extern const gs_ptr_procs_t ptr_name_index_procs;
+#define ptr_name_index_type (&ptr_name_index_procs)
+
 /*
  * Define the type for a GC root.
  */
@@ -357,6 +361,8 @@ struct_proc_reloc_ptrs(basic_reloc_ptrs);
   (pep->ptr = sdata, pep->size = ssize, ptr_const_string_type)
 #define ENUM_CONST_STRING(sptr)	/* pointer to gs_const_string */\
   ENUM_CONST_STRING2((sptr)->data, (sptr)->size)
+#define ENUM_NAME_INDEX(name) /* name (as a long index) */\
+    (pep->size = (uint)name, ptr_name_index_type)
 extern gs_ptr_type_t
     enum_bytestring(enum_ptr_t *pep, const gs_bytestring *pbs);
 #define ENUM_BYTESTRING(ptr)	/* pointer to gs_bytestring */\
@@ -374,6 +380,8 @@ extern gs_ptr_type_t
     (((const typ *)vptr)->elt.persistent ? 0 : ENUM_STRING(&((const typ *)vptr)->elt))
 #define ENUM_CONST_STRING_ELT(typ, elt)\
   ENUM_CONST_STRING(&((const typ *)vptr)->elt)
+#define ENUM_NAME_INDEX_ELT(typ, elt) /* name (as a long index) */\
+    (pep->size = (uint)(((const typ *)vptr)->elt), ptr_name_index_type)
 
 #define ENUM_PTR(i, typ, elt)\
   case i: return ENUM_OBJ_ELT(typ, elt)
diff --git a/gs/psi/igc.c b/gs/psi/igc.c
index 7a2c5c36d..00957d52c 100644
--- a/gs/psi/igc.c
+++ b/gs/psi/igc.c
@@ -82,6 +82,8 @@ static ptr_proc_unmark(ptr_struct_unmark);
 static ptr_proc_mark(ptr_struct_mark);
 static ptr_proc_unmark(ptr_string_unmark);
 static ptr_proc_mark(ptr_string_mark);
+static ptr_proc_unmark(ptr_name_index_unmark);
+static ptr_proc_mark(ptr_name_index_mark);
 /*ptr_proc_unmark(ptr_ref_unmark); *//* in igc.h */
 /*ptr_proc_mark(ptr_ref_mark); *//* in igc.h */
 static ptr_proc_reloc(igc_reloc_struct_ptr, void);
@@ -98,7 +100,7 @@ static const gc_procs_with_refs_t igc_procs = {
 /* Pointer type descriptors. */
 /* Note that the trace/mark routine has special knowledge of ptr_ref_type */
 /* and ptr_struct_type -- it assumes that no other types have embedded */
-/* pointers.  Note also that the reloc procedures for string and ref */
+/* pointers.  Note also that the reloc procedures for string, ref and name */
 /* pointers are never called. */
 typedef ptr_proc_reloc((*ptr_proc_reloc_t), void);
 const gs_ptr_procs_t ptr_struct_procs =
@@ -109,6 +111,8 @@ const gs_ptr_procs_t ptr_const_string_procs =
 {ptr_string_unmark, ptr_string_mark, NULL};
 const gs_ptr_procs_t ptr_ref_procs =
 {ptr_ref_unmark, ptr_ref_mark, NULL};
+const gs_ptr_procs_t ptr_name_index_procs =
+{ptr_name_index_unmark, ptr_name_index_mark, NULL};
 
 /* ------ Main program ------ */
 
@@ -584,6 +588,13 @@ ptr_string_unmark(enum_ptr_t *pep, gc_state_t * gcst)
     discard(gc_string_mark(pep->ptr, pep->size, false, gcst));
 }
 
+/* Unmark a single name. */
+static void
+ptr_name_index_unmark(enum_ptr_t *pep, gc_state_t * gcst)
+{
+    /* Do nothing */
+}
+
 /* Unmark the objects in a chunk. */
 static void
 gc_objects_clear_marks(const gs_memory_t *mem, chunk_t * cp)
@@ -1081,6 +1092,13 @@ ptr_string_mark(enum_ptr_t *pep, gc_state_t * gcst)
     return gc_string_mark(pep->ptr, pep->size, true, gcst);
 }
 
+/* Mark a name.  Return true if new mark. */
+static bool
+ptr_name_index_mark(enum_ptr_t *pep, gc_state_t * gcst)
+{
+    return names_mark_index(gcst->heap->gs_lib_ctx->gs_name_table, pep->size);
+}
+
 /* Finish tracing by marking names. */
 static bool
 gc_trace_finish(gc_state_t * pstate)
diff --git a/pl/plplatf.c b/pl/plplatf.c
index 7fb8732be..1ba9dc2f5 100644
--- a/pl/plplatf.c
+++ b/pl/plplatf.c
@@ -60,6 +60,7 @@ void
 gs_reloc_const_string(gs_const_string *sptr, gc_state_t *gcst)
 {
 }
+const gs_ptr_procs_t ptr_name_index_procs = { NULL, NULL, NULL };
 
 /* Stub for abnormal termination */
 void