Support objcopy changing compression to or from zstd
Commit 2cac01e3ffff lacked support for objcopy changing compression
style. Add that support, which meant a rewrite of
bfd_compress_section_contents. In the process I've fixed some memory
leaks.
* compress.c (bfd_is_section_compressed_info): Rename from
bfd_is_section_compressed_with_header and add ch_type param
to return compression header ch_type field.
Update all callers.
(decompress_section_contents): Remove buffer and size params.
Rewrite. Update callers.
(bfd_init_section_compress_status): Free contents on failure.
(bfd_compress_section): Likewise.
* elf.c (_bfd_elf_make_section_from_shdr): Support objcopy
changing between any of the three compression schemes. Report
"unable to compress/decompress" rather than "unable to
initialize compress/decompress status" on compress/decompress
failures.
* bfd-in2.h: Regenerate.
3 files changed
