Introduce obstack_strndup

This introduces obstack_strndup and changes gdb to use it.

Note that obstack_strndup works like savestring, and not exactly like
xstrndup.  The difference is that obstack_strndup uses the passed-in
length, while xstrndup uses strnlen to choose the length.

gdb/ChangeLog
2019-08-06  Tom Tromey  <tom@tromey.com>

	* stabsread.c (patch_block_stabs, read_one_struct_field)
	(read_enum_type): Use obstack_strndup.
	* rust-exp.y (rust_parser::copy_name): Use obstack_strndup.
	* gdb_obstack.h (obstack_strndup): Use obstack_strndup.
	* dwarf2read.c (guess_full_die_structure_name)
	(anonymous_struct_prefix): Use obstack_strndup.
	* dbxread.c (cp_set_block_scope): Use obstack_strndup.
	* c-exp.y (yylex): Use obstack_strndup.
	* ada-exp.y (write_object_renaming, write_ambiguous_var)
	(write_var_or_type): Use obstack_strndup.

1 files changed, 11 insertions, 0 deletions

diff --git a/gdb/gdb_obstack.h b/gdb/gdb_obstack.h
index db849a0..3d6a010 100644
--- a/gdb/gdb_obstack.h
+++ b/gdb/gdb_obstack.h
@@ -105,6 +105,17 @@ obstack_strdup (struct obstack *obstackp, const std::string &string)
 				 string.size ());
 }
 
+/* Duplicate the first N characters of STRING, returning a
+   \0-terminated string that's allocated on the obstack OBSTACKP.
+   Note that exactly N characters are copied, even if STRING is
+   shorter.  */
+
+static inline char *
+obstack_strndup (struct obstack *obstackp, const char *string, size_t n)
+{
+  return (char *) obstack_copy0 (obstackp, string, n);
+}
+
 /* An obstack that frees itself on scope exit.  */
 struct auto_obstack : obstack
 {