--- /dev/null
+/* bfdlink.h -- header file for BFD link routines
+ Copyright 1993 Free Software Foundation, Inc.
+ Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support.
+
+This file is part of BFD, the Binary File Descriptor library.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#ifndef BFDLINK_H
+#define BFDLINK_H
+
+/* Which symbols to strip during a link. */
+enum bfd_link_strip
+{
+ strip_none, /* Don't strip any symbols. */
+ strip_debugger, /* Strip debugging symbols. */
+ strip_some, /* keep_hash is the list of symbols to keep. */
+ strip_all /* Strip all symbols. */
+};
+
+/* Which local symbols to discard during a link. This is irrelevant
+ if strip_all is used. */
+enum bfd_link_discard
+{
+ discard_none, /* Don't discard any locals. */
+ discard_l, /* Discard locals with a certain prefix. */
+ discard_all /* Discard all locals. */
+};
+\f
+/* These are the possible types of an entry in the BFD link hash
+ table. */
+
+enum bfd_link_hash_type
+{
+ bfd_link_hash_new, /* Symbol is new. */
+ bfd_link_hash_undefined, /* Symbol seen before, but undefined. */
+ bfd_link_hash_weak, /* Symbol is weak and undefined. */
+ bfd_link_hash_defined, /* Symbol is defined. */
+ bfd_link_hash_common, /* Symbol is common. */
+ bfd_link_hash_indirect, /* Symbol is an indirect link. */
+ bfd_link_hash_warning /* Like indirect, but warn if referenced. */
+};
+
+/* The linking routines use a hash table which uses this structure for
+ its elements. */
+
+struct bfd_link_hash_entry
+{
+ /* Base hash table entry structure. */
+ struct bfd_hash_entry root;
+ /* Type of this entry. */
+ enum bfd_link_hash_type type;
+ /* Whether this symbol has been written out. */
+ boolean written;
+ /* Undefined and common entries are kept in a linked list through
+ this field. This field is not in the union because that would
+ force us to remove entries from the list when we changed their
+ type, which would force the list to be doubly linked, which would
+ waste more memory. When an undefined or common symbol is
+ created, it should be added to this list, the head of which is in
+ the link hash table itself. As symbols are defined, they need
+ not be removed from the list; anything which reads the list must
+ doublecheck the symbol type. Weak symbols are not kept on this
+ list. */
+ struct bfd_link_hash_entry *next;
+ /* A union of information depending upon the type. */
+ union
+ {
+ /* Nothing is kept for bfd_hash_new. */
+ /* bfd_link_hash_undefined, bfd_link_hash_weak. */
+ struct
+ {
+ bfd *abfd; /* BFD symbol was found in. */
+ } undef;
+ /* bfd_link_hash_defined. */
+ struct
+ {
+ bfd_vma value; /* Symbol value. */
+ asection *section; /* Symbol section. */
+ } def;
+ /* bfd_link_hash_indirect, bfd_link_hash_warning. */
+ struct
+ {
+ struct bfd_link_hash_entry *link; /* Real symbol. */
+ const char *warning; /* Warning (bfd_link_hash_warning only). */
+ } i;
+ /* bfd_link_hash_common. */
+ struct
+ {
+ bfd_vma size; /* Common symbol size. */
+ asection *section; /* Symbol section. */
+ } c;
+ } u;
+};
+
+/* This is the link hash table. It is a derived class of
+ bfd_hash_table. */
+
+struct bfd_link_hash_table
+{
+ /* The hash table itself. */
+ struct bfd_hash_table table;
+ /* The back end which created this hash table. This indicates the
+ type of the entries in the hash table, which is sometimes
+ important information when linking object files of different
+ types together. */
+ bfd_target *creator;
+ /* A linked list of undefined and common symbols, linked through the
+ next field in the bfd_link_hash_entry structure. */
+ struct bfd_link_hash_entry *undefs;
+ /* Entries are added to the tail of the undefs list. */
+ struct bfd_link_hash_entry *undefs_tail;
+};
+
+/* Look up an entry in a link hash table. If FOLLOW is true, this
+ follows bfd_link_hash_indirect and bfd_link_hash_warning links to
+ the real symbol. */
+extern struct bfd_link_hash_entry *bfd_link_hash_lookup
+ PARAMS ((struct bfd_link_hash_table *, const char *, boolean create,
+ boolean copy, boolean follow));
+
+/* Traverse a link hash table. */
+extern void bfd_link_hash_traverse
+ PARAMS ((struct bfd_link_hash_table *,
+ boolean (*) (struct bfd_link_hash_entry *, PTR),
+ PTR));
+
+/* Add an entry to the undefs list. */
+extern void bfd_link_add_undef
+ PARAMS ((struct bfd_link_hash_table *, struct bfd_link_hash_entry *));
+\f
+/* This structure holds all the information needed to communicate
+ between BFD and the linker when doing a link. */
+
+struct bfd_link_info
+{
+ /* Function callbacks. */
+ const struct bfd_link_callbacks *callbacks;
+ /* true if BFD should generate a relocateable object file. */
+ boolean relocateable;
+ /* Which symbols to strip. */
+ enum bfd_link_strip strip;
+ /* Which local symbols to discard. */
+ enum bfd_link_discard discard;
+ /* The local symbol prefix to discard if using discard_l. */
+ unsigned int lprefix_len;
+ const char *lprefix;
+ /* true if symbols should be retained in memory, false if they
+ should be freed and reread. */
+ boolean keep_memory;
+ /* The list of input BFD's involved in the link. These are chained
+ together via the link_next field. */
+ bfd *input_bfds;
+ /* If a symbol should be created for each input BFD, this is section
+ where those symbols should be placed. It must be a section in
+ the output BFD. It may be NULL, in which case no such symbols
+ will be created. This is to support CREATE_OBJECT_SYMBOLS in the
+ linker command language. */
+ asection *create_object_symbols_section;
+ /* Hash table handled by BFD. */
+ struct bfd_link_hash_table *hash;
+ /* Hash table of symbols to keep. This is NULL unless strip is
+ strip_some. */
+ struct bfd_hash_table *keep_hash;
+ /* Hash table of symbols to report back via notice_callback. If
+ this is NULL no symbols are reported back. */
+ struct bfd_hash_table *notice_hash;
+};
+
+/* This structures holds a set of callback functions. These are
+ called by the BFD linker routines. The first argument to each
+ callback function is the bfd_link_info structure being used. Each
+ function returns a boolean value. If the function returns false,
+ then the BFD function which called it will return with a failure
+ indication. */
+
+struct bfd_link_callbacks
+{
+ /* A function which is called when an object is added from an
+ archive. ABFD is the archive element being added. NAME is the
+ name of the symbol which caused the archive element to be pulled
+ in. */
+ boolean (*add_archive_element) PARAMS ((struct bfd_link_info *,
+ bfd *abfd,
+ const char *name));
+ /* A function which is called when a symbol is found with multiple
+ definitions. NAME is the symbol which is defined multiple times.
+ OBFD is the old BFD, OSEC is the old section, OVAL is the old
+ value, NBFD is the new BFD, NSEC is the new section, and NVAL is
+ the new value. OBFD may be NULL. OSEC and NSEC may be
+ bfd_com_section or bfd_ind_section. */
+ boolean (*multiple_definition) PARAMS ((struct bfd_link_info *,
+ const char *name,
+ bfd *obfd,
+ asection *osec,
+ bfd_vma oval,
+ bfd *nbfd,
+ asection *nsec,
+ bfd_vma nval));
+ /* A function which is called when a common symbol is defined
+ multiple times. NAME is the symbol appearing multiple times.
+ OBFD is the BFD of the existing symbol. OTYPE is the type of the
+ existing symbol, either bfd_link_hash_defined or
+ bfd_link_hash_common. If OTYPE is bfd_link_hash_common, OSIZE is
+ the size of the existing symbol. NBFD is the BFD of the new
+ symbol. NTYPE is the type of the new symbol, either
+ bfd_link_hash_defined or bfd_link_hash_common. If NTYPE is
+ bfd_link_hash_common, NSIZE is the size of the new symbol. */
+ boolean (*multiple_common) PARAMS ((struct bfd_link_info *,
+ const char *name,
+ bfd *obfd,
+ enum bfd_link_hash_type otype,
+ bfd_vma osize,
+ bfd *nbfd,
+ enum bfd_link_hash_type ntype,
+ bfd_vma nsize));
+ /* A function which is called to add a symbol to a set. ENTRY is
+ the link hash table entry for the set itself (e.g.,
+ __CTOR_LIST__). RELOC is the relocation to use for an entry in
+ the set when generating a relocateable file, and is also used to
+ get the size of the entry when generating an executable file.
+ ABFD, SEC and VALUE identify the value to add to the set. */
+ boolean (*add_to_set) PARAMS ((struct bfd_link_info *,
+ struct bfd_link_hash_entry *entry,
+ bfd_reloc_code_real_type reloc,
+ bfd *abfd, asection *sec, bfd_vma value));
+ /* A function which is called when the name of a g++ constructor or
+ destructor is found. This is only called by some object file
+ formats. CONSTRUCTOR is true for a constructor, false for a
+ destructor. This will use BFD_RELOC_CTOR when generating a
+ relocateable file. NAME is the name of the symbol found. ABFD,
+ SECTION and VALUE are the value of the symbol. */
+ boolean (*constructor) PARAMS ((struct bfd_link_info *,
+ boolean constructor,
+ const char *name, bfd *abfd, asection *sec,
+ bfd_vma value));
+ /* A function which is called when there is a reference to a warning
+ symbol. WARNING is the warning to be issued. */
+ boolean (*warning) PARAMS ((struct bfd_link_info *,
+ const char *warning));
+ /* A function which is called when a relocation is attempted against
+ an undefined symbol. NAME is the symbol which is undefined.
+ ABFD, SECTION and ADDRESS identify the location from which the
+ reference is made. */
+ boolean (*undefined_symbol) PARAMS ((struct bfd_link_info *,
+ const char *name, bfd *abfd,
+ asection *section, bfd_vma address));
+ /* A function which is called when a reloc overflow occurs. NAME is
+ the name of the symbol or section the reloc is against,
+ RELOC_NAME is the name of the relocation, and ADDEND is any
+ addend that is used. ABFD, SECTION and ADDRESS identify the
+ location at which the overflow occurs; if this is the result of a
+ bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then
+ ABFD will be NULL. */
+ boolean (*reloc_overflow) PARAMS ((struct bfd_link_info *,
+ const char *name,
+ const char *reloc_name, bfd_vma addend,
+ bfd *abfd, asection *section,
+ bfd_vma address));
+ /* A function which is called when a dangerous reloc is performed.
+ The canonical example is an a29k IHCONST reloc which does not
+ follow an IHIHALF reloc. MESSAGE is an appropriate message.
+ ABFD, SECTION and ADDRESS identify the location at which the
+ problem occurred; if this is the result of a
+ bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then
+ ABFD will be NULL. */
+ boolean (*reloc_dangerous) PARAMS ((struct bfd_link_info *,
+ const char *message,
+ bfd *abfd, asection *section,
+ bfd_vma address));
+ /* A function which is called when a reloc is found to be attached
+ to a symbol which is not being written out. NAME is the name of
+ the symbol. ABFD, SECTION and ADDRESS identify the location of
+ the reloc; if this is the result of a
+ bfd_section_reloc_link_order or bfd_symbol_reloc_link_order, then
+ ABFD will be NULL. */
+ boolean (*unattached_reloc) PARAMS ((struct bfd_link_info *,
+ const char *name,
+ bfd *abfd, asection *section,
+ bfd_vma address));
+ /* A function which is called when a symbol in notice_hash is
+ defined or referenced. NAME is the symbol. ABFD, SECTION and
+ ADDRESS are the value of the symbol. If SECTION is
+ bfd_und_section, this is a reference. */
+ boolean (*notice) PARAMS ((struct bfd_link_info *, const char *name,
+ bfd *abfd, asection *section, bfd_vma address));
+};
+\f
+/* The linker builds link_order structures which tell the code how to
+ include input data in the output file. */
+
+/* These are the types of link_order structures. */
+
+enum bfd_link_order_type
+{
+ bfd_undefined_link_order, /* Undefined. */
+ bfd_indirect_link_order, /* Built from a section. */
+ bfd_fill_link_order, /* Fill with a 16 bit constant. */
+ bfd_section_reloc_link_order, /* Relocate against a section. */
+ bfd_symbol_reloc_link_order /* Relocate against a symbol. */
+};
+
+/* This is the link_order structure itself. These form a chain
+ attached to the section whose contents they are describing. */
+
+struct bfd_link_order
+{
+ /* Next link_order in chain. */
+ struct bfd_link_order *next;
+ /* Type of link_order. */
+ enum bfd_link_order_type type;
+ /* Offset within output section. */
+ bfd_vma offset;
+ /* Size within output section. */
+ bfd_size_type size;
+ /* Type specific information. */
+ union
+ {
+ struct
+ {
+ /* Section to include. If this is used, then
+ section->output_section must be the section the
+ link_order is attached to, section->output_offset must
+ equal the link_order offset field, and section->_raw_size
+ must equal the link_order size field. Maybe these
+ restrictions should be relaxed someday. */
+ asection *section;
+ } indirect;
+ struct
+ {
+ /* Value to fill with. */
+ unsigned int value;
+ } fill;
+ struct
+ {
+ /* Description of reloc to generate. Used for
+ bfd_section_reloc_link_order and
+ bfd_symbol_reloc_link_order. */
+ struct bfd_link_order_reloc *p;
+ } reloc;
+ } u;
+};
+
+/* A linker order of type bfd_section_reloc_link_order or
+ bfd_symbol_reloc_link_order means to create a reloc against a
+ section or symbol, respectively. This is used to implement -Ur to
+ generate relocs for the constructor tables. The
+ bfd_link_order_reloc structure describes the reloc that BFD should
+ create. It is similar to a arelent, but I didn't use arelent
+ because the linker does not know anything about most symbols, and
+ any asymbol structure it creates will be partially meaningless.
+ This information could logically be in the bfd_link_order struct,
+ but I didn't want to waste the space since these types of relocs
+ are relatively rare. */
+
+struct bfd_link_order_reloc
+{
+ /* Reloc type. */
+ bfd_reloc_code_real_type reloc;
+
+ union
+ {
+ /* For type bfd_section_reloc_link_order, this is the section
+ the reloc should be against. This must be a section in the
+ output BFD, not any of the input BFDs. */
+ asection *section;
+ /* For type bfd_symbol_reloc_link_order, this is the name of the
+ symbol the reloc should be against. */
+ const char *name;
+ } u;
+
+ /* Addend to use. The object file should contain zero. The BFD
+ backend is responsible for filling in the contents of the object
+ file correctly. For some object file formats (e.g., COFF) the
+ addend must be stored into in the object file, and for some
+ (e.g., SPARC a.out) it is kept in the reloc. */
+ bfd_vma addend;
+};
+
+/* Allocate a new link_order for a section. */
+extern struct bfd_link_order *bfd_new_link_order PARAMS ((bfd *, asection *));
+
+#endif
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