gdb: New function to open source file and compute line charpos data

Every place that a symtab's line_charpos data is loaded always follows
the same pattern, so create a new function to contain this logic and
make use of it throughout GDB.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* source-cache.c (source_cache::get_plain_source_lines): Use
	open_source_file_with_line_charpos instead of just
	open_source_file, remove call to find_source_lines.
	(source_cache::get_source_lines): Likewise.
	* source.c (find_source_lines): Make static.
	(get_filename_and_charpos): Renamed into...
	(open_source_file_with_line_charpos): ..this along with changes to
	return a scoped_fd, and some other minor clean ups.
	(identify_source_line): Use open_source_file_with_line_charpos.
	(search_command_helper): Use open_source_file_with_line_charpos
	instead of just open_source_file, remove call to
	find_source_lines.
	* source.h (open_source_file_with_line_charpos): Declare new
	function.
	(find_source_lines): Delete declaration.

1 files changed, 5 insertions, 6 deletions

diff --git a/gdb/source.h b/gdb/source.h
index f1b5f6e..7ea826a 100644
--- a/gdb/source.h
+++ b/gdb/source.h
@@ -76,6 +76,11 @@ extern scoped_fd find_and_open_source (const char *filename,
    negative number for error.  */
 extern scoped_fd open_source_file (struct symtab *s);
 
+/* Open a source file given a symtab S (by calling open_source_file), then
+   ensure the line_charpos data is initialised for symtab S before
+   returning.  */
+extern scoped_fd open_source_file_with_line_charpos (struct symtab *s);
+
 extern gdb::unique_xmalloc_ptr<char> rewrite_source_path (const char *path);
 
 extern const char *symtab_to_fullname (struct symtab *s);
@@ -84,12 +89,6 @@ extern const char *symtab_to_fullname (struct symtab *s);
    filename.  It depends on 'set filename-display' value.  */
 extern const char *symtab_to_filename_for_display (struct symtab *symtab);
 
-/* Create and initialize the table S->line_charpos that records the
-   positions of the lines in the source file, which is assumed to be
-   open on descriptor DESC.  All set S->nlines to the number of such
-   lines.  */
-extern void find_source_lines (struct symtab *s, int desc);
-
 /* Return the first line listed by print_source_lines.  Used by
    command interpreters to request listing from a previous point.  If
    0, then no source lines have yet been listed since the last time