libdw: Add dwarf_default_lower_bound.

Add dwarf_default_lower_bound to get the default lower bound for a language
when not given as attribute for an subrange type. Implementation extracted
from dwarf_aggregate_size.

Add a test to check all known language codes are handled.

Signed-off-by: Mark Wielaard <[email protected]>

3 files changed, 93 insertions, 2 deletions

diff --git a/tests/ChangeLog b/tests/ChangeLog
index 519f25a3..fa3f94ed 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,3 +1,10 @@
+2017-07-26  Mark Wielaard  <[email protected]>
+
+	* dwarf_default_lower_bound.c: New test.
+	* Makefile.am (check_PROGRAMS): Add dwarf_default_lower_bound.
+	(TESTS): Likewise.
+	(dwarf_default_lower_bound_LDADD): New variable.
+
 2017-07-21  Mark Wielaard  <[email protected]>
 
 	* get-lines.c (main): Add dwarf_line_file test.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 407c0511..3735084f 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -55,7 +55,7 @@ check_PROGRAMS = arextract arsymtest newfile saridx scnnames sectiondump \
 		  getsrc_die strptr newdata elfstrtab dwfl-proc-attach \
 		  elfshphehdr elfstrmerge dwelfgnucompressed elfgetchdr \
 		  elfgetzdata elfputzdata zstrptr emptyfile vendorelf \
-		  fillfile
+		  fillfile dwarf_default_lower_bound
 
 asm_TESTS = asm-tst1 asm-tst2 asm-tst3 asm-tst4 asm-tst5 \
 	    asm-tst6 asm-tst7 asm-tst8 asm-tst9
@@ -135,7 +135,7 @@ TESTS = run-arextract.sh run-arsymtest.sh newfile test-nlist \
 	run-elfgetzdata.sh run-elfputzdata.sh run-zstrptr.sh \
 	run-compress-test.sh \
 	run-readelf-zdebug.sh run-readelf-zdebug-rel.sh \
-	emptyfile vendorelf fillfile
+	emptyfile vendorelf fillfile dwarf_default_lower_bound
 
 if !BIARCH
 export ELFUTILS_DISABLE_BIARCH = 1
@@ -505,6 +505,7 @@ zstrptr_LDADD = $(libelf)
 emptyfile_LDADD = $(libelf)
 vendorelf_LDADD = $(libelf)
 fillfile_LDADD = $(libelf)
+dwarf_default_lower_bound_LDADD = $(libdw)
 
 # We want to test the libelf header against the system elf.h header.
 # Don't include any -I CPPFLAGS.
diff --git a/tests/dwarf_default_lower_bound.c b/tests/dwarf_default_lower_bound.c
new file mode 100644
index 00000000..d57424fc
--- /dev/null
+++ b/tests/dwarf_default_lower_bound.c
@@ -0,0 +1,83 @@
+/* Test all DW_LANG constants are handled by dwarf_default_lower_bound.
+
+   Copyright (C) 2016 Red Hat, Inc.
+   This file is part of elfutils.
+
+   This file 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.
+
+   elfutils 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/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <dwarf.h>
+#include ELFUTILS_HEADER(dw)
+#include "../libdw/known-dwarf.h"
+
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+static void
+test_lang (const char *name, int lang)
+{
+  Dwarf_Sword low;
+  int res = dwarf_default_lower_bound (lang, &low);
+
+  /* Assembler is special, it doesn't really have arrays.  */
+  if (lang == DW_LANG_Mips_Assembler)
+    {
+      if (res == 0)
+	{
+	  printf ("%s shouldn't have a known lower bound\n", name);
+	  exit (-1);
+	}
+      printf ("%s: <unknown>\n", name);
+      return;
+    }
+
+  if (res != 0)
+    {
+      printf ("dwarf_default_lower_bound failed (%d) for %s\n", res, name);
+      exit (-1);
+    }
+
+  /* All currently known lower bounds are either zero or one, but
+     they don't have to.  Update test once one is a different value.  */
+  if (low != 0 && low != 1)
+    {
+      printf ("unexpected lower bound %" PRId64 " for %s\n", low, name);
+      exit (-1);
+    }
+
+  printf ("%s: %" PRId64 "\n", name, low);
+}
+
+int
+main (int argc __attribute__ ((unused)), char *argv[] __attribute__ ((unused)))
+{
+  Dwarf_Sword low;
+  /* Bad language code must fail.  */
+  if (dwarf_default_lower_bound (-1, &low) == 0)
+    {
+      printf ("Bad lang code -1 succeeded (%" PRId64 ")\n", low);
+      exit (-1);
+    }
+
+  /* Test all known language codes.  */
+#define DWARF_ONE_KNOWN_DW_LANG(NAME, CODE) test_lang (#NAME, CODE);
+  DWARF_ALL_KNOWN_DW_LANG
+#undef DWARF_ONE_KNOWN_DW_LANG
+
+  return 0;
+}