Applied patch series for LD plugin interface (six parts).

[PATCH] Add infrastructure for plugin API; functionality to follow.

    include/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 1/6).
	* plugin-api.h (LDPT_GNU_LD_VERSION): New ld_plugin_tag enum member.

    ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 1/6).
	* configure.in: Add AC_CHECKs for file io and dlfcn headers and
	functions and AC_SEARCH for -ldl.
	(enable_plugins): New shell variable set if above tests find dlopen
	functionality.
	(ENABLE_PLUGINS): Add related automake conditional.
	* configure: Regenerate.
	* config.in: Likewise.
	* Makefile.am (PLUGIN_C): Declare plugin C source file, conditional
	on ENABLE_PLUGINS being defined.
	(PLUGIN_H): Likewise for header file.
	(PLUGIN_OBJECT): Likewise for object file.
	(PLUGIN_CFLAGS): Likewise -D flag required to compile plugin support.
	(AM_CPPFLAGS): Use PLUGIN_CFLAGS.
	(CFILES): Use PLUGIN_C.
	(HFILES): Use PLUGIN_H.
	(OFILES): Use PLUGIN_OBJECT.
	(ld_new_SOURCES): Use PLUGIN_C.
	(noinst_LTLIBRARIES)[ENABLE_PLUGINS]: Declare test plugin.
	(libldtestplug_la_SOURCES)[ENABLE_PLUGINS]: Add automake definition
	for test plugin.
	(libldtestplug_la_CFLAGS)[ENABLE_PLUGINS]: Likewise.
	(libldtestplug_la_LDFLAGS)[ENABLE_PLUGINS]: Likewise.
	* Makefile.in: Regenerate.
	* sysdep.h: Include stdarg.h, unistd.h and one of fcntl.h or
	sys/file.h where available.  Include dlfcn.h when ENABLE_PLUGINS.
	(O_RDONLY): Supply default definition likewise to bfd's sysdep.h
	(O_WRONLY): Likewise.
	(O_RDWR): Likewise.
	(O_ACCMODE): Likewise.
	(O_BINARY): Likewise.
	(SEEK_SET): Likewise.
	(SEEK_CUR): Likewise.
	(SEEK_END): Likewise.
	* ldmisc.c (vfinfo): Make non-static.  Add %p format char.
	* ldmisc.h (vfinfo): Declare extern prototype.
	* lexsup.c (enum option_values)[ENABLE_PLUGINS]: Add new entries for
	OPTION_PLUGIN and OPTION_PLUGIN_OPT.
	(ld_options[])[ENABLE_PLUGINS]: Add option data for the above two.
	(parse_args)[ENABLE_PLUGINS]: Handle them, and load all plugins once
	option parsing is complete.
	* ldmain.c (main)[ENABLE_PLUGINS]: Call plugin cleanup hooks just
	after lang_finish.
	* plugin.c: New source file.
	* plugin.h: Likewise new header.
	* testplug.c: New source file.

    ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 1/6).
	* ld-bootstrap/bootstrap.exp: Skip static tests also if LD plugins
	are enabled.
	* lib/ld-lib.exp (proc regexp_diff): Extend verbose debug output.
	(proc set_file_contents): Write a file with the supplied content.
	(run_ld_link_tests): Add new 'ld' action to test linker output.
	(proc check_plugin_api_available): Return true if linker under test
	supports the plugin API.
	* ld-plugin/func.c: New test source file.
	* ld-plugin/main.c: Likewise.
	* ld-plugin/text.c: Likewise.
	* ld-plugin/plugin-1.d: New dump test output pattern script.
	* ld-plugin/plugin-2.d: Likewise.
	* ld-plugin/plugin-3.d: Likewise.
	* ld-plugin/plugin-4.d: Likewise.
	* ld-plugin/plugin-5.d: Likewise.
	* ld-plugin/plugin.exp: New test control script.
---
[PATCH] Implement claim file and all symbols read hooks and add symbols callback.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 2/6).
	* ldfile.c (ldfile_try_open_bfd)[ENABLE_PLUGINS]: Don't return early
	during compat checks if they pass, instead offer any successfully
	opened and accepted file to the plugin claim file hooks chain.  Create
	a dummy bfd to accept symbols added by the plugin, if the plugin
	claims the file.
	* ldlang.c (lang_process)[ENABLE_PLUGINS]: Call plugin all symbols
	read hook chain before ldemul_after_open.
	* ldlang.h (struct lang_input_statement_struct): Add new single-bit
	'claimed' flag.
	* plugin.c (IRONLY_SUFFIX): New macro for dummy bfd file suffix.
	(IRONLY_SUFFIX_LEN): Length of the above string.
	(plugin_get_ir_dummy_bfd): New function to create the dummy bfd used
	to store symbols for ir-only files.
	(is_ir_dummy_bfd): New function to check if a bfd is ir-only.
	(asymbol_from_plugin_symbol): New function converts symbol formats.
	(add_symbols): Call it to convert plugin syms to bfd syms and add
	them to the dummy bfd.
	* plugin.h: Add missing include guards.
	(plugin_get_ir_dummy_bfd): Add prototype.
	(is_ir_dummy_bfd): Likewise.
	* testplug.c (TV_MESSAGE): New helper macro.
	(struct claim_file): New struct.
	(claim_file_t): New typedef.
	(tag_names[]): Make static and const.
	(claimfiles_list): New variable.
	(claimfiles_tail_chain_ptr): Likewise.
	(last_claimfile): Likewise.
	(record_claim_file): Record a file to claim on a singly-linked list.
	(parse_symdefstr): Parse an ASCII representation of a symbol from a
	plugin option into the fields of a struct ld_plugin_symbol.
	(record_claimed_file_symbol):  Use it to parse plugin option for
	adding a symbol.
	(parse_option): Parse claim file and add symbol options.
	(dump_tv_tag): Use TV_MESSAGE.
	(onload): Likewise.
	(onclaim_file): Make static.  Use TV_MESSAGE.  Scan list of files to
	claim and claim this file if required, adding any symbols specified.
	(onall_symbols_read): Make static and use TV_MESSAGE.
	(oncleanup): Likewise.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 2/6).
	* ld-plugin/plugin-3.d: Enable regexes for new functionality.
	* ld-plugin/plugin-5.d: Likewise.
	* ld-plugin/plugin-6.d: New testcase.
	* ld-plugin/plugin-7.d: Likewise.
	* ld-plugin/plugin.exp: Use 'nm' on compiled test objects to determine
	whether symbols in plugin arguments need an underscore prefix.  Add
	new plugin-6.d and plugin-7.d testcases.
---
[PATCH] Implement get symbols callback.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 3/6).
	* ldmain.c (notice)[ENABLE_PLUGINS]: Call plugin_notice.
	* plugin.c (non_ironly_hash): Add new bfd hash table.
	(plugin_load_plugins): Exit early if no plugins to load.  If plugins
	do load successfully, set notice_all flag in link info.
	(get_symbols): Implement.
	(plugin_load_plugins): Exit early if no plugins to load, else after
	loading plugins successfully enable notice_all mode.
	(init_non_ironly_hash): Lazily init non_ironly_hash table.
	(plugin_notice): Record symbols referenced from non-IR files in the
	non_ironly_hash.  Suppress tracing, cref generation and nocrossrefs
	tracking for symbols from dummy IR bfds.
	* plugin.h: Fix formatting.
	(plugin_notice): Add prototype.
	* testplug.c (dumpresolutions): New global var.
	(parse_options): Accept "dumpresolutions".
	(onall_symbols_read): Get syms and dump resolutions if it was given.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 3/6).
	* ld-plugin/plugin-8.d: New testcase.
	* ld-plugin/plugin.exp: Invoke it.
---
[PATCH] Implement add input file, add input lib and set extra lib path callbacks.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 4/6).
	* ldlang.c (lang_process)[ENABLE_PLUGINS]: Move invocation of
	plugin_call_all_symbols_read to before setting of gc_sym_list, and
	open any new input files that may have been added during it.
	* ldmain.c (multiple_definition)[ENABLE_PLUGINS]: Call out to
	plugin_multiple_definition and let it have first say over what to do
	with the clashing definitions.
	* plugin.c (no_more_claiming): New boolean variable.
	(plugin_cached_allow_multiple_defs): Likewise.
	(add_input_file): Implement.
	(add_input_library): Likewise.
	(set_extra_library_path): Likewise.
	(plugin_call_claim_file): Don't do anything when no_more_claiming set.
	(plugin_call_all_symbols_read): Set it.  Disable link info
	"allow_multiple_definition" flag, but cache its value.
	(plugin_multiple_definition): New function.
	* plugin.h (plugin_multiple_definition): Add prototype.
	* testplug.c (addfile_enum_t): New enumerated typedef.
	(add_file_t): New struct typedef.
	(addfiles_list): New variable.
	(addfiles_tail_chain_ptr): Likewise.
	(record_add_file): New function.
	(parse_option): Parse "add:", "lib:" and "dir:" options and call it.
	(onall_symbols_read): Iterate the list of new files, libs and dirs,
	adding them.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 4/6).
	* ld-plugin/plugin-9.d: New testcase.
	* ld-plugin/plugin.exp: Invoke it.
---
[PATCH] Add ELF symbol visibility support to plugin interface.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 5/6).
	* plugin.c (asymbol_from_plugin_symbol): If the bfd is an ELF bfd,
	find the elf symbol data and set the visibility in the st_other field.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 5/6).
	* ld-plugin/plugin-ignore.d: New dump test control script.
	* ld-plugin/plugin-vis-1.d: Likewise.
	* ld-plugin/plugin.exp: Add list of ELF-only tests and run them if
	testing on an ELF target.
---
[PATCH] Add archive support to plugin interface.

  bfd/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* aoutx.h (aout_link_check_ar_symbols): Take new "subsbfd" reference
	parameter and pass it when invoking add_archive_element callback.
	(aout_link_check_archive_element): Handle substitute bfd if it
	was set during add_archive_element callback in the above.
	* cofflink.c (coff_link_check_ar_symbols): Take new "subsbfd" reference
	parameter and pass it when invoking add_archive_element callback.
	(coff_link_check_archive_element): Handle substitute bfd if it
	was set during add_archive_element callback in the above.
	* ecoff.c (read_ext_syms_and_strs): New function holds symbol-reading
	code factored-out from ecoff_link_check_archive_element.
	(reread_ext_syms_and_strs): Clear old symbols and call it.
	(ecoff_link_check_archive_element):  Use the above.  Handle substitute
	BFD if one is set by add_archive_element callback.
	(ecoff_link_add_archive_symbols): Likewise allow bfd substitution.
	* elflink.c (elf_link_add_archive_symbols): Likewise.
	* linker.c (generic_link_check_archive_element): Likewise.
	* pdp11.c (aout_link_check_ar_symbols): Take new "subsbfd" reference
	parameter and pass it when invoking add_archive_element callback.
	(aout_link_check_archive_element): Handle substitute bfd if it was
	set during add_archive_element callback in the above.
	* vms-alpha.c (alpha_vms_link_add_archive_symbols): Handle substitute
	BFD if one is set by add_archive_element callback.
	* xcofflink.c (xcoff_link_check_dynamic_ar_symbols): Take new "subsbfd"
	reference parameter and pass it when invoking add_archive_element
	callback.
	(xcoff_link_check_ar_symbols): Likewise.
	(xcoff_link_check_archive_element): Handle bfd substitution if it was
	set by callback in the above.

  include/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* bfdlink.h (struct_bfd_link_callbacks): Document new argument
	to add_archive_element callback used to return a replacement bfd which
	is to be added to the hash table in place of the original element.

  ld/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* ldlang.c (load_symbols): Handle bfd subsitution when calling the
	add_archive_element callback.
	* ldmain.c (add_archive_element)[ENABLE_PLUGINS]: Offer the archive
	member to the plugins and if claimed set "subsbfd" output parameter to
	point to the dummy IR-only BFD.

  ld/testsuite/ChangeLog:

2010-10-14  Dave Korn  <dave.korn.cygwin@gmail.com>

	Apply LD plugin patch series (part 6/6).
	* ld-plugin/plugin-10.d: New dump test control script.
	* ld-plugin/plugin-11.d: Likewise.
	* ld-plugin/plugin.exp: Run them.
---

1 files changed, 61 insertions, 2 deletions

diff --git a/ld/ldfile.c b/ld/ldfile.c
index 4661897..2695905 100644
--- a/ld/ldfile.c
+++ b/ld/ldfile.c
@@ -34,6 +34,10 @@
 #include "ldemul.h"
 #include "libiberty.h"
 #include "filenames.h"
+#ifdef ENABLE_PLUGINS
+#include "plugin-api.h"
+#include "plugin.h"
+#endif /* ENABLE_PLUGINS */
 
 const char * ldfile_input_filename;
 bfd_boolean  ldfile_assumed_script = FALSE;
@@ -150,7 +154,12 @@ ldfile_try_open_bfd (const char *attempt,
      compatible with the output file.  If it isn't, keep searching.
      If we can't open the file as an object file, stop the search
      here.  If we are statically linking, ensure that we don't link
-     a dynamic object.  */
+     a dynamic object.
+
+     In the code below, it's OK to exit early if the check fails,
+     closing the checked BFD and returning FALSE, but if the BFD
+     checks out compatible, do not exit early returning TRUE, or
+     the plugins will not get a chance to claim the file.  */
 
   if (entry->search_dirs_flag || !entry->dynamic)
     {
@@ -259,7 +268,7 @@ ldfile_try_open_bfd (const char *attempt,
 		      return FALSE;
 		    }
 		}
-	      return TRUE;
+	      goto success;
 	    }
 
 	  if (!entry->dynamic && (entry->the_bfd->flags & DYNAMIC) != 0)
@@ -289,7 +298,57 @@ ldfile_try_open_bfd (const char *attempt,
 	    }
 	}
     }
+success:
+#ifdef ENABLE_PLUGINS
+  /* If plugins are active, they get first chance to claim
+     any successfully-opened input file.  We skip archives
+     here; the plugin wants us to offer it the individual
+     members when we enumerate them, not the whole file.  We
+     also ignore corefiles, because that's just weird.  It is
+     a needed side-effect of calling  bfd_check_format with
+     bfd_object that it sets the bfd's arch and mach, which
+     will be needed when and if we want to bfd_create a new
+     one using this one as a template.  */
+  if (bfd_check_format (entry->the_bfd, bfd_object))
+    {
+      int fd = open (attempt, O_RDONLY | O_BINARY);
+      if (fd >= 0)
+	{
+	  struct ld_plugin_input_file file;
+	  int claimed = 0;
+
+	  file.name = attempt;
+	  file.offset = 0;
+	  file.filesize = lseek (fd, 0, SEEK_END);
+	  file.fd = fd;
+	  /* We create a dummy BFD, initially empty, to house
+	     whatever symbols the plugin may want to add.  */
+	  file.handle = plugin_get_ir_dummy_bfd (attempt, entry->the_bfd);
+	  if (plugin_call_claim_file (&file, &claimed))
+	    einfo (_("%P%F: %s: plugin reported error claiming file\n"),
+	      plugin_error_plugin ());
+	  if (claimed)
+	    {
+	      /* Discard the real file's BFD and substitute the dummy one.  */
+	      bfd_close (entry->the_bfd);
+	      entry->the_bfd = file.handle;
+	      entry->claimed = TRUE;
+	      bfd_make_readable (entry->the_bfd);
+	    }
+	  else
+	    {
+	      /* If plugin didn't claim the file, we don't need the fd or the
+	         dummy bfd.  Can't avoid speculatively creating it, alas.  */
+	      bfd_close_all_done (file.handle);
+	      close (fd);
+	      entry->claimed = FALSE;
+	    }
+	}
+    }
+#endif /* ENABLE_PLUGINS */
 
+  /* It opened OK, the format checked out, and the plugins have had
+     their chance to claim it, so this is success.  */
   return TRUE;
 }