/* plugin-api.h -- External linker plugin API. */
-/* Copyright 2009 Free Software Foundation, Inc.
+/* Copyright (C) 2009-2023 Free Software Foundation, Inc.
Written by Cary Coutant <ccoutant@google.com>.
This file is part of binutils.
#ifndef PLUGIN_API_H
#define PLUGIN_API_H
+#ifdef HAVE_STDINT_H
#include <stdint.h>
+#elif defined(HAVE_INTTYPES_H)
+#include <inttypes.h>
+#endif
#include <sys/types.h>
+#if !defined(HAVE_STDINT_H) && !defined(HAVE_INTTYPES_H) && \
+ !defined(UINT64_MAX) && !defined(uint64_t)
+#error cannot find uint64_t type
+#endif
+
+/* Detect endianess based on __BYTE_ORDER__ macro. */
+#if defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && \
+ defined(__ORDER_LITTLE_ENDIAN__) && defined(__ORDER_PDP_ENDIAN__)
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define PLUGIN_LITTLE_ENDIAN 1
+#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#define PLUGIN_BIG_ENDIAN 1
+#elif __BYTE_ORDER__ == __ORDER_PDP_ENDIAN__
+#define PLUGIN_PDP_ENDIAN 1
+#endif
+#else
+/* Older GCC releases (<4.6.0) can make detection from glibc macros. */
+#if defined(__GLIBC__) || defined(__GNU_LIBRARY__) || defined(__ANDROID__)
+#include <endian.h>
+#ifdef __BYTE_ORDER
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define PLUGIN_LITTLE_ENDIAN 1
+#elif __BYTE_ORDER == __BIG_ENDIAN
+#define PLUGIN_BIG_ENDIAN 1
+#endif
+#endif
+#endif
+/* Include all necessary header files based on target. */
+#if defined(__SVR4) && defined(__sun)
+#include <sys/byteorder.h>
+#endif
+#if defined(__FreeBSD__) || defined(__NetBSD__) || \
+ defined(__DragonFly__) || defined(__minix)
+#include <sys/endian.h>
+#endif
+#if defined(__OpenBSD__)
+#include <machine/endian.h>
+#endif
+/* Detect endianess based on _BYTE_ORDER. */
+#ifdef _BYTE_ORDER
+#if _BYTE_ORDER == _LITTLE_ENDIAN
+#define PLUGIN_LITTLE_ENDIAN 1
+#elif _BYTE_ORDER == _BIG_ENDIAN
+#define PLUGIN_BIG_ENDIAN 1
+#endif
+#endif
+/* Detect based on _WIN32. */
+#if defined(_WIN32)
+#define PLUGIN_LITTLE_ENDIAN 1
+#endif
+/* Detect based on __BIG_ENDIAN__ and __LITTLE_ENDIAN__ */
+#ifdef __LITTLE_ENDIAN__
+#define PLUGIN_LITTLE_ENDIAN 1
+#endif
+#ifdef __BIG_ENDIAN__
+#define PLUGIN_BIG_ENDIAN 1
+#endif
+#endif
#ifdef __cplusplus
extern "C"
{
LDPO_REL,
LDPO_EXEC,
- LDPO_DYN
+ LDPO_DYN,
+ LDPO_PIE
};
/* An input file managed by the plugin library. */
{
char *name;
char *version;
- int def;
+ /* This is for compatibility with older ABIs. The older ABI defined
+ only 'def' field. */
+#if PLUGIN_BIG_ENDIAN == 1
+ char unused;
+ char section_kind;
+ char symbol_type;
+ char def;
+#elif PLUGIN_LITTLE_ENDIAN == 1
+ char def;
+ char symbol_type;
+ char section_kind;
+ char unused;
+#elif PLUGIN_PDP_ENDIAN == 1
+ char symbol_type;
+ char def;
+ char unused;
+ char section_kind;
+#else
+#error "Could not detect architecture endianess"
+#endif
int visibility;
uint64_t size;
char *comdat_key;
int resolution;
};
+/* An object's section. */
+
+struct ld_plugin_section
+{
+ const void* handle;
+ unsigned int shndx;
+};
+
/* Whether the symbol is a definition, reference, or common, weak or not. */
enum ld_plugin_symbol_kind
LDPV_HIDDEN
};
+/* The type of the symbol. */
+
+enum ld_plugin_symbol_type
+{
+ LDST_UNKNOWN,
+ LDST_FUNCTION,
+ LDST_VARIABLE
+};
+
+enum ld_plugin_symbol_section_kind
+{
+ LDSSK_DEFAULT,
+ LDSSK_BSS
+};
+
/* How a symbol is resolved. */
enum ld_plugin_symbol_resolution
LDPR_RESOLVED_EXEC,
/* This symbol was resolved by a definition in a shared object. */
- LDPR_RESOLVED_DYN
+ LDPR_RESOLVED_DYN,
+
+ /* This is the prevailing definition of the symbol, with no
+ references from regular objects. It is only referenced from IR
+ code, but the symbol is exported and may be referenced from
+ a dynamic object (not seen at link time). */
+ LDPR_PREVAILING_DEF_IRONLY_EXP
};
/* The plugin library's "claim file" handler. */
(*ld_plugin_claim_file_handler) (
const struct ld_plugin_input_file *file, int *claimed);
+/* The plugin library's "claim file" handler, version 2. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_claim_file_handler_v2) (
+ const struct ld_plugin_input_file *file, int *claimed, int known_used);
+
/* The plugin library's "all symbols read" handler. */
typedef
enum ld_plugin_status
(*ld_plugin_register_claim_file) (ld_plugin_claim_file_handler handler);
+/* The linker's interface for registering the "claim file" handler,
+ version 2. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_register_claim_file_v2) (ld_plugin_claim_file_handler_v2 handler);
+
/* The linker's interface for registering the "all symbols read" handler. */
typedef
(*ld_plugin_get_input_file) (const void *handle,
struct ld_plugin_input_file *file);
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_view) (const void *handle, const void **viewp);
+
/* The linker's interface for releasing the input file. */
typedef
typedef
enum ld_plugin_status
-(*ld_plugin_add_input_file) (char *pathname);
+(*ld_plugin_add_input_file) (const char *pathname);
/* The linker's interface for adding a library that should be searched. */
typedef
enum ld_plugin_status
-(*ld_plugin_add_input_library) (char *libname);
+(*ld_plugin_add_input_library) (const char *libname);
+
+/* The linker's interface for adding a library path that should be searched. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_set_extra_library_path) (const char *path);
/* The linker's interface for issuing a warning or error message. */
enum ld_plugin_status
(*ld_plugin_message) (int level, const char *format, ...);
+/* The linker's interface for retrieving the number of sections in an object.
+ The handle is obtained in the claim_file handler. This interface should
+ only be invoked in the claim_file handler. This function sets *COUNT to
+ the number of sections in the object. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_count) (const void* handle, unsigned int *count);
+
+/* The linker's interface for retrieving the section type of a specific
+ section in an object. This interface should only be invoked in the
+ claim_file handler. This function sets *TYPE to an ELF SHT_xxx value. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_type) (const struct ld_plugin_section section,
+ unsigned int *type);
+
+/* The linker's interface for retrieving the name of a specific section in
+ an object. This interface should only be invoked in the claim_file handler.
+ This function sets *SECTION_NAME_PTR to a null-terminated buffer allocated
+ by malloc. The plugin must free *SECTION_NAME_PTR. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_name) (const struct ld_plugin_section section,
+ char **section_name_ptr);
+
+/* The linker's interface for retrieving the contents of a specific section
+ in an object. This interface should only be invoked in the claim_file
+ handler. This function sets *SECTION_CONTENTS to point to a buffer that is
+ valid until clam_file handler returns. It sets *LEN to the size of the
+ buffer. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_contents) (const struct ld_plugin_section section,
+ const unsigned char **section_contents,
+ size_t* len);
+
+/* The linker's interface for specifying the desired order of sections.
+ The sections should be specifed using the array SECTION_LIST in the
+ order in which they should appear in the final layout. NUM_SECTIONS
+ specifies the number of entries in each array. This should be invoked
+ in the all_symbols_read handler. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_update_section_order) (const struct ld_plugin_section *section_list,
+ unsigned int num_sections);
+
+/* The linker's interface for specifying that reordering of sections is
+ desired so that the linker can prepare for it. This should be invoked
+ before update_section_order, preferably in the claim_file handler. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_allow_section_ordering) (void);
+
+/* The linker's interface for specifying that a subset of sections is
+ to be mapped to a unique segment. If the plugin wants to call
+ unique_segment_for_sections, it must call this function from a
+ claim_file_handler or when it is first loaded. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_allow_unique_segment_for_sections) (void);
+
+/* The linker's interface for specifying that a specific set of sections
+ must be mapped to a unique segment. ELF segments do not have names
+ and the NAME is used as the name of the newly created output section
+ that is then placed in the unique PT_LOAD segment. FLAGS is used to
+ specify if any additional segment flags need to be set. For instance,
+ a specific segment flag can be set to identify this segment. Unsetting
+ segment flags that would be set by default is not possible. The
+ parameter SEGMENT_ALIGNMENT when non-zero will override the default. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_unique_segment_for_sections) (
+ const char* segment_name,
+ uint64_t segment_flags,
+ uint64_t segment_alignment,
+ const struct ld_plugin_section * section_list,
+ unsigned int num_sections);
+
+/* The linker's interface for retrieving the section alignment requirement
+ of a specific section in an object. This interface should only be invoked in the
+ claim_file handler. This function sets *ADDRALIGN to the ELF sh_addralign
+ value of the input section. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_alignment) (const struct ld_plugin_section section,
+ unsigned int *addralign);
+
+/* The linker's interface for retrieving the section size of a specific section
+ in an object. This interface should only be invoked in the claim_file handler.
+ This function sets *SECSIZE to the ELF sh_size
+ value of the input section. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_input_section_size) (const struct ld_plugin_section section,
+ uint64_t *secsize);
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_new_input_handler) (const struct ld_plugin_input_file *file);
+
+/* The linker's interface for registering the "new_input" handler. This handler
+ will be notified when a new input file has been added after the
+ all_symbols_read event, allowing the plugin to, for example, set a unique
+ segment for sections in plugin-generated input files. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_register_new_input) (ld_plugin_new_input_handler handler);
+
+/* The linker's interface for getting the list of wrapped symbols using the
+ --wrap option. This sets *NUM_SYMBOLS to number of wrapped symbols and
+ *WRAP_SYMBOL_LIST to the list of wrapped symbols. */
+
+typedef
+enum ld_plugin_status
+(*ld_plugin_get_wrap_symbols) (uint64_t *num_symbols,
+ const char ***wrap_symbol_list);
+
enum ld_plugin_level
{
LDPL_INFO,
LDPL_FATAL
};
+/* Contract between a plug-in and a linker. */
+
+enum linker_api_version
+{
+ /* The linker/plugin do not implement any of the API levels below, the API
+ is determined solely via the transfer vector. */
+ LAPI_V0,
+
+ /* API level v1. The linker provides get_symbols_v3, add_symbols_v2,
+ the plugin will use that and not any lower versions.
+ claim_file is thread-safe on the plugin side and
+ add_symbols on the linker side. */
+ LAPI_V1
+};
+
+/* The linker's interface for API version negotiation. A plug-in calls
+ the function (with its IDENTIFIER and VERSION), plus minimal and maximal
+ version of linker_api_version is provided. Linker then returns selected
+ API version and provides its IDENTIFIER and VERSION. The returned value
+ by linker must be in range [MINIMAL_API_SUPPORTED, MAXIMAL_API_SUPPORTED].
+ Identifier pointers remain valid as long as the plugin is loaded. */
+
+typedef
+int
+(*ld_plugin_get_api_version) (const char *plugin_identifier,
+ const char *plugin_version,
+ int minimal_api_supported,
+ int maximal_api_supported,
+ const char **linker_identifier,
+ const char **linker_version);
+
/* Values for the tv_tag field of the transfer vector. */
enum ld_plugin_tag
{
- LDPT_NULL = 0,
+ LDPT_NULL,
LDPT_API_VERSION,
LDPT_GOLD_VERSION,
LDPT_LINKER_OUTPUT,
LDPT_MESSAGE,
LDPT_GET_INPUT_FILE,
LDPT_RELEASE_INPUT_FILE,
- LDPT_ADD_INPUT_LIBRARY
+ LDPT_ADD_INPUT_LIBRARY,
+ LDPT_OUTPUT_NAME,
+ LDPT_SET_EXTRA_LIBRARY_PATH,
+ LDPT_GNU_LD_VERSION,
+ LDPT_GET_VIEW,
+ LDPT_GET_INPUT_SECTION_COUNT,
+ LDPT_GET_INPUT_SECTION_TYPE,
+ LDPT_GET_INPUT_SECTION_NAME,
+ LDPT_GET_INPUT_SECTION_CONTENTS,
+ LDPT_UPDATE_SECTION_ORDER,
+ LDPT_ALLOW_SECTION_ORDERING,
+ LDPT_GET_SYMBOLS_V2,
+ LDPT_ALLOW_UNIQUE_SEGMENT_FOR_SECTIONS,
+ LDPT_UNIQUE_SEGMENT_FOR_SECTIONS,
+ LDPT_GET_SYMBOLS_V3,
+ LDPT_GET_INPUT_SECTION_ALIGNMENT,
+ LDPT_GET_INPUT_SECTION_SIZE,
+ LDPT_REGISTER_NEW_INPUT_HOOK,
+ LDPT_GET_WRAP_SYMBOLS,
+ LDPT_ADD_SYMBOLS_V2,
+ LDPT_GET_API_VERSION,
+ LDPT_REGISTER_CLAIM_FILE_HOOK_V2
};
/* The plugin transfer vector. */
int tv_val;
const char *tv_string;
ld_plugin_register_claim_file tv_register_claim_file;
+ ld_plugin_register_claim_file_v2 tv_register_claim_file_v2;
ld_plugin_register_all_symbols_read tv_register_all_symbols_read;
ld_plugin_register_cleanup tv_register_cleanup;
ld_plugin_add_symbols tv_add_symbols;
ld_plugin_add_input_file tv_add_input_file;
ld_plugin_message tv_message;
ld_plugin_get_input_file tv_get_input_file;
+ ld_plugin_get_view tv_get_view;
ld_plugin_release_input_file tv_release_input_file;
ld_plugin_add_input_library tv_add_input_library;
+ ld_plugin_set_extra_library_path tv_set_extra_library_path;
+ ld_plugin_get_input_section_count tv_get_input_section_count;
+ ld_plugin_get_input_section_type tv_get_input_section_type;
+ ld_plugin_get_input_section_name tv_get_input_section_name;
+ ld_plugin_get_input_section_contents tv_get_input_section_contents;
+ ld_plugin_update_section_order tv_update_section_order;
+ ld_plugin_allow_section_ordering tv_allow_section_ordering;
+ ld_plugin_allow_unique_segment_for_sections tv_allow_unique_segment_for_sections;
+ ld_plugin_unique_segment_for_sections tv_unique_segment_for_sections;
+ ld_plugin_get_input_section_alignment tv_get_input_section_alignment;
+ ld_plugin_get_input_section_size tv_get_input_section_size;
+ ld_plugin_register_new_input tv_register_new_input;
+ ld_plugin_get_wrap_symbols tv_get_wrap_symbols;
+ ld_plugin_get_api_version tv_get_api_version;
} tv_u;
};