Introduce buildsym-legacy.h

This introduces a new header, buildsym-legacy.h, and changes all the
symbol readers to use it.  The idea is to put the function-based
interface, that relies on the buildsym_compunit global, into a
separate header.  Then when a symbol reader is updated to use the new
interface, it can simply not include buildsym-legacy.h, so it's easy
to be sure that the new API is used everywhere.

gdb/ChangeLog
2018-07-20  Tom Tromey  <tom@tromey.com>

	* xcoffread.c: Include buildsym-legacy.h.
	* windows-nat.c: Include buildsym-legacy.h.
	* stabsread.c: Include buildsym-legacy.h.
	* mdebugread.c: Include buildsym-legacy.h.
	* buildsym-legacy.h: New file.
	* buildsym-legacy.c: New file, from buildsym.c.
	* go32-nat.c: Include buildsym-legacy.h.
	* dwarf2read.c: Include buildsym-legacy.h.
	* dbxread.c: Include buildsym-legacy.h.
	* cp-namespace.c: Include buildsym-legacy.h.
	* coffread.c: Include buildsym-legacy.h.
	* buildsym.h: Move some contents to buildsym-legacy.h.
	* buildsym.c: Include buildsym-legacy.h.  Move many functions to
	buildsym-legacy.c.
	* Makefile.in (HFILES_NO_SRCDIR): Add buildsym-legacy.h.

1 files changed, 210 insertions, 0 deletions

diff --git a/gdb/buildsym-legacy.h b/gdb/buildsym-legacy.h
new file mode 100644
index 0000000..78a5644
--- /dev/null
+++ b/gdb/buildsym-legacy.h
@@ -0,0 +1,210 @@
+/* Build symbol tables in GDB's internal format - legacy APIs
+   Copyright (C) 1986-2018 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#if !defined (LEGACY_BUILDSYM_H)
+#define LEGACY_BUILDSYM_H 1
+
+#include "buildsym.h"
+
+/* This module provides definitions used for creating and adding to
+   the symbol table.  These routines are called from various symbol-
+   file-reading routines.  This file holds the legacy API, which
+   relies on a global variable to work properly.  New or maintained
+   symbol readers should use the builder API in buildsym.h.
+
+   The basic way this module is used is as follows:
+
+   scoped_free_pendings free_pending;
+   cust = start_symtab (...);
+   ... read debug info ...
+   cust = end_symtab (...);
+
+   The compunit symtab pointer ("cust") is returned from both start_symtab
+   and end_symtab to simplify the debug info readers.
+
+   There are minor variations on this, e.g., dwarf2read.c splits end_symtab
+   into two calls: end_symtab_get_static_block, end_symtab_from_static_block,
+   but all debug info readers follow this basic flow.
+
+   Reading DWARF Type Units is another variation:
+
+   scoped_free_pendings free_pending;
+   cust = start_symtab (...);
+   ... read debug info ...
+   cust = end_expandable_symtab (...);
+
+   And then reading subsequent Type Units within the containing "Comp Unit"
+   will use a second flow:
+
+   scoped_free_pendings free_pending;
+   cust = restart_symtab (...);
+   ... read debug info ...
+   cust = augment_type_symtab (...);
+
+   dbxread.c and xcoffread.c use another variation:
+
+   scoped_free_pendings free_pending;
+   cust = start_symtab (...);
+   ... read debug info ...
+   cust = end_symtab (...);
+   ... start_symtab + read + end_symtab repeated ...
+*/
+
+class scoped_free_pendings
+{
+public:
+
+  scoped_free_pendings () = default;
+  ~scoped_free_pendings ();
+
+  DISABLE_COPY_AND_ASSIGN (scoped_free_pendings);
+};
+
+extern struct block *finish_block (struct symbol *symbol,
+				   struct pending_block *old_blocks,
+				   const struct dynamic_prop *static_link,
+				   CORE_ADDR start,
+				   CORE_ADDR end);
+
+extern void record_block_range (struct block *,
+                                CORE_ADDR start, CORE_ADDR end_inclusive);
+
+extern void start_subfile (const char *name);
+
+extern void patch_subfile_names (struct subfile *subfile, const char *name);
+
+extern void push_subfile ();
+
+extern const char *pop_subfile ();
+
+extern struct block *end_symtab_get_static_block (CORE_ADDR end_addr,
+						  int expandable,
+						  int required);
+
+extern struct compunit_symtab *
+  end_symtab_from_static_block (struct block *static_block,
+				int section, int expandable);
+
+extern struct compunit_symtab *end_symtab (CORE_ADDR end_addr, int section);
+
+extern struct compunit_symtab *end_expandable_symtab (CORE_ADDR end_addr,
+						      int section);
+
+extern void augment_type_symtab (void);
+
+extern struct context_stack *push_context (int desc, CORE_ADDR valu);
+
+extern struct context_stack pop_context ();
+
+extern record_line_ftype record_line;
+
+extern struct compunit_symtab *start_symtab (struct objfile *objfile,
+					     const char *name,
+					     const char *comp_dir,
+					     CORE_ADDR start_addr,
+					     enum language language);
+
+extern void restart_symtab (struct compunit_symtab *cust,
+			    const char *name, CORE_ADDR start_addr);
+
+/* Record the name of the debug format in the current pending symbol
+   table.  FORMAT must be a string with a lifetime at least as long as
+   the symtab's objfile.  */
+
+extern void record_debugformat (const char *format);
+
+/* Record the name of the debuginfo producer (usually the compiler) in
+   the current pending symbol table.  PRODUCER must be a string with a
+   lifetime at least as long as the symtab's objfile.  */
+
+extern void record_producer (const char *producer);
+
+/* Set the name of the last source file.  NAME is copied by this
+   function.  */
+
+extern void set_last_source_file (const char *name);
+
+/* Fetch the name of the last source file.  */
+
+extern const char *get_last_source_file (void);
+
+/* Return the compunit symtab object.
+   It is only valid to call this between calls to start_symtab and the
+   end_symtab* functions.  */
+
+extern struct compunit_symtab *buildsym_compunit_symtab (void);
+
+/* Return the macro table.
+   Initialize it if this is the first use.
+   It is only valid to call this between calls to start_symtab and the
+   end_symtab* functions.  */
+
+extern struct macro_table *get_macro_table (void);
+
+/* Set the last source start address.  Can only be used between
+   start_symtab and end_symtab* calls.  */
+
+extern void set_last_source_start_addr (CORE_ADDR addr);
+
+/* Get the last source start address.  Can only be used between
+   start_symtab and end_symtab* calls.  */
+
+extern CORE_ADDR get_last_source_start_addr ();
+
+/* Return the local using directives.  */
+
+extern struct using_direct **get_local_using_directives ();
+
+/* Set the list of local using directives.  */
+
+extern void set_local_using_directives (struct using_direct *new_local);
+
+/* Return the global using directives.  */
+
+extern struct using_direct **get_global_using_directives ();
+
+/* True if the context stack is empty.  */
+
+extern bool outermost_context_p ();
+
+/* Return the top of the context stack, or nullptr if there is an
+   entry.  */
+
+extern struct context_stack *get_current_context_stack ();
+
+/* Return the context stack depth.  */
+
+extern int get_context_stack_depth ();
+
+/* Return the current subfile.  */
+
+extern struct subfile *get_current_subfile ();
+
+/* Return the local symbol list.  */
+
+extern struct pending **get_local_symbols ();
+
+/* Return the file symbol list.  */
+
+extern struct pending **get_file_symbols ();
+
+/* Return the global symbol list.  */
+
+extern struct pending **get_global_symbols ();
+
+#endif /* defined (LEGACY_BUILDSYM_H) */