Compression tidy and fixes

Tidies:
- Move stuff from bfd-in.h and libbfd.c to compress.c
- Delete COMPRESS_DEBUG from enum compressed_debug_section_type
- Move compress_debug field out of link_info to ld_config.
Fixes:
- Correct test in bfd_convert_section_setup to use obfd flags,
  not ibfd.
- Apply bfd_applicable_file_flags to compression bfd flags added
  by gas and ld to the output bfd.

bfd/
	* bfd-in.h (enum compressed_debug_section_type),
	(struct compressed_type_tuple),
	(bfd_get_compression_algorithm),
	(bfd_get_compression_algorithm_name),
	* libbfd.c (compressed_debug_section_names),
	(bfd_get_compression_algorithm),
	(bfd_get_compression_algorithm_name): Move..
	* compress.c: ..to here, deleting COMPRESS_DEBUG from
	enum compressed_debug_section_type.
	(bfd_convert_section_setup): Test obfd flags not ibfd for
	compression flags.
	* elf.c (elf_fake_sections): Replace link_info->compress_debug
	test with abfd->flags test.
	* bfd-in2.h: Regenerate.
binutils/
	* objcopy.c (copy_file): Tidy setting of bfd compress flags.
	Expand comment.
gas/
	* write.c (compress_debug): Test bfd compress flags rather than
	flag_compress_debug.
	(write_object_file): Apply bfd_applicable_file_flags to compress
	debug flags added to output bfd.
include/
	* bfdlink.h (struct bfd_link_info): Delete compress_debug.
ld/
	* ld.h (ld_config_type): Add compress_debug.
	* emultempl/elf.em: Replace references to link_info.compress_debug
	with config.compress_debug.
	* lexsup.c (elf_static_list_options): Likewise.
	* ldmain.c (main): Likewise.  Apply bfd_applicable_file_flags
	to compress debug flags added to output bfd.

1 files changed, 68 insertions, 1 deletions

diff --git a/bfd/compress.c b/bfd/compress.c
index 5ea7cd9..2943492 100644
--- a/bfd/compress.c
+++ b/bfd/compress.c
@@ -27,11 +27,30 @@
 #include "elf-bfd.h"
 #include "libbfd.h"
 #include "safe-ctype.h"
+#include "libiberty.h"
 
 #define MAX_COMPRESSION_HEADER_SIZE 24
 
 /*
 CODE_FRAGMENT
+.{* Types of compressed DWARF debug sections.  *}
+.enum compressed_debug_section_type
+.{
+.  COMPRESS_DEBUG_NONE = 0,
+.  COMPRESS_DEBUG_GNU_ZLIB = 1 << 1,
+.  COMPRESS_DEBUG_GABI_ZLIB = 1 << 2,
+.  COMPRESS_DEBUG_ZSTD = 1 << 3,
+.  COMPRESS_UNKNOWN = 1 << 4
+.};
+.
+.{* Tuple for compressed_debug_section_type and their name.  *}
+.struct compressed_type_tuple
+.{
+.  enum compressed_debug_section_type type;
+.  const char *name;
+.};
+.
+.{* Compression header ch_type values.  *}
 .enum compression_type
 .{
 .  ch_none = 0,
@@ -66,6 +85,54 @@ CODE_FRAGMENT
 .
 */
 
+/* Display texts for type of compressed DWARF debug sections.  */
+static const struct compressed_type_tuple compressed_debug_section_names[] =
+{
+  { COMPRESS_DEBUG_NONE, "none" },
+  { COMPRESS_DEBUG_GABI_ZLIB, "zlib" },
+  { COMPRESS_DEBUG_GNU_ZLIB, "zlib-gnu" },
+  { COMPRESS_DEBUG_GABI_ZLIB, "zlib-gabi" },
+  { COMPRESS_DEBUG_ZSTD, "zstd" },
+};
+
+/*
+FUNCTION
+	bfd_get_compression_algorithm
+SYNOPSIS
+	enum compressed_debug_section_type
+	  bfd_get_compression_algorithm (const char *name);
+DESCRIPTION
+	Return compressed_debug_section_type from a string representation.
+*/
+enum compressed_debug_section_type
+bfd_get_compression_algorithm (const char *name)
+{
+  for (unsigned i = 0; i < ARRAY_SIZE (compressed_debug_section_names); ++i)
+    if (strcasecmp (compressed_debug_section_names[i].name, name) == 0)
+      return compressed_debug_section_names[i].type;
+
+  return COMPRESS_UNKNOWN;
+}
+
+/*
+FUNCTION
+	bfd_get_compression_algorithm_name
+SYNOPSIS
+	const char *bfd_get_compression_algorithm_name
+	  (enum compressed_debug_section_type type);
+DESCRIPTION
+	Return compression algorithm name based on the type.
+*/
+const char *
+bfd_get_compression_algorithm_name (enum compressed_debug_section_type type)
+{
+  for (unsigned i = 0; i < ARRAY_SIZE (compressed_debug_section_names); ++i)
+    if (type == compressed_debug_section_names[i].type)
+      return compressed_debug_section_names[i].name;
+
+  return NULL;
+}
+
 /*
 FUNCTION
 	bfd_update_compression_header
@@ -249,7 +316,7 @@ bfd_convert_section_setup (bfd *ibfd, asection *isec, bfd *obfd,
     {
       const char *name = *new_name;
 
-      if ((ibfd->flags & (BFD_DECOMPRESS | BFD_COMPRESS_GABI)) != 0)
+      if ((obfd->flags & (BFD_DECOMPRESS | BFD_COMPRESS_GABI)) != 0)
 	{
 	  /* When we decompress or compress with SHF_COMPRESSED,
 	     convert section name from .zdebug_* to .debug_*.  */