[PATCH v3] objcopy: Add ELF header e_flags option in objcopy.

[liuzhensong]

Specify flags when copying binary to ELF.
The flags is treated as an absolute number to be
stored in the e_flags field of the ELF header.

Usage:
  objcopy -I binary -O target --elf-eflags=val bin_file  elf_file

binutils/
  * objcopy.c
  * doc/binutils.texi:Add the new objcopy option.
---
 binutils/doc/binutils.texi |  7 +++++++
 binutils/objcopy.c         | 16 ++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/binutils/doc/binutils.texi b/binutils/doc/binutils.texi
index 2c234c682aa..65230775b29 100644
--- a/binutils/doc/binutils.texi
+++ b/binutils/doc/binutils.texi
@@ -1326,6 +1326,7 @@ objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
         [@option{--merge-notes}]
         [@option{--no-merge-notes}]
         [@option{--verilog-data-width=@var{val}}]
+        [@option{--elf-eflags=}@var{value}]
         [@option{-v}|@option{--verbose}]
         [@option{-V}|@option{--version}]
         [@option{--help}] [@option{--info}]
@@ -2187,6 +2188,12 @@ For Verilog output, this options controls the number of bytes
 converted for each output data element.  The input target controls the
 endianness of the conversion.
 
+@item --elf-eflags=@var{value}
+Meaningful only for ELF output.  Use @var{value} as e_flags of the
+output.  This is useful for changing the e_flags of an existing binary.
+The @var{value} is treated as an absolute number to be stored in the
+e_flags field of the ELF header.
+
 @item -v
 @itemx --verbose
 Verbose output: list all object files modified.  In the case of
diff --git a/binutils/objcopy.c b/binutils/objcopy.c
index 6fb31c8cac7..3c1eaf5ec1a 100644
--- a/binutils/objcopy.c
+++ b/binutils/objcopy.c
@@ -303,6 +303,10 @@ enum long_section_name_handling
    This is also the only behaviour for 'strip'.  */
 static enum long_section_name_handling long_section_names = KEEP;
 
+/* Specify ELF header e_flags?  */
+static bool elf_eflags_set = false;
+static unsigned int elf_eflags = 0;
+
 /* 150 isn't special; it's just an arbitrary non-ASCII char value.  */
 enum command_line_switch
 {
@@ -321,6 +325,7 @@ enum command_line_switch
   OPTION_DEBUGGING,
   OPTION_DECOMPRESS_DEBUG_SECTIONS,
   OPTION_DUMP_SECTION,
+  OPTION_ELF_EFLAGS,
   OPTION_ELF_STT_COMMON,
   OPTION_EXTRACT_DWO,
   OPTION_EXTRACT_SYMBOL,
@@ -443,6 +448,7 @@ static struct option copy_options[] =
   {"discard-all", no_argument, 0, 'x'},
   {"discard-locals", no_argument, 0, 'X'},
   {"dump-section", required_argument, 0, OPTION_DUMP_SECTION},
+  {"elf-eflags", required_argument, 0, OPTION_ELF_EFLAGS},
   {"elf-stt-common", required_argument, 0, OPTION_ELF_STT_COMMON},
   {"enable-deterministic-archives", no_argument, 0, 'D'},
   {"extract-dwo", no_argument, 0, OPTION_EXTRACT_DWO},
@@ -684,6 +690,7 @@ copy_usage (FILE *stream, int exit_status)
      --elf-stt-common=[yes|no]     Generate ELF common symbols with STT_COMMON\n\
                                      type\n\
      --verilog-data-width <number> Specifies data width, in bytes, for verilog output\n\
+     --elf-eflags=<value>          Set e_flags to <value> for ELF output\n\
   -M  --merge-notes                Remove redundant entries in note sections\n\
       --no-merge-notes             Do not attempt to remove redundant notes (default)\n\
   -v --verbose                     List all object files modified\n\
@@ -3496,6 +3503,10 @@ copy_object (bfd *ibfd, bfd *obfd, const bfd_arch_info_type *input_arch)
 	}
     }
 
+  if (bfd_get_flavour (obfd) == bfd_target_elf_flavour
+      && elf_eflags_set)
+    elf_elfheader (obfd)->e_flags = elf_eflags;
+
   return true;
 }
 
@@ -5863,6 +5874,11 @@ copy_main (int argc, char *argv[])
 	    fatal (_("verilog data width must be at least 1 byte"));
 	  break;
 
+	case OPTION_ELF_EFLAGS:
+	  elf_eflags_set = true;
+	  elf_eflags = parse_vma (optarg, "--elf-eflags");
+	  break;
+
 	case 0:
 	  /* We've been given a long option.  */
 	  break;
-- 
2.31.1