| /* Object file "section" support for the BFD library. |
| Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, |
| 2000, 2001, 2002 |
| Free Software Foundation, Inc. |
| Written by 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| |
| /* |
| SECTION |
| Sections |
| |
| The raw data contained within a BFD is maintained through the |
| section abstraction. A single BFD may have any number of |
| sections. It keeps hold of them by pointing to the first; |
| each one points to the next in the list. |
| |
| Sections are supported in BFD in <<section.c>>. |
| |
| @menu |
| @* Section Input:: |
| @* Section Output:: |
| @* typedef asection:: |
| @* section prototypes:: |
| @end menu |
| |
| INODE |
| Section Input, Section Output, Sections, Sections |
| SUBSECTION |
| Section input |
| |
| When a BFD is opened for reading, the section structures are |
| created and attached to the BFD. |
| |
| Each section has a name which describes the section in the |
| outside world---for example, <<a.out>> would contain at least |
| three sections, called <<.text>>, <<.data>> and <<.bss>>. |
| |
| Names need not be unique; for example a COFF file may have several |
| sections named <<.data>>. |
| |
| Sometimes a BFD will contain more than the ``natural'' number of |
| sections. A back end may attach other sections containing |
| constructor data, or an application may add a section (using |
| <<bfd_make_section>>) to the sections attached to an already open |
| BFD. For example, the linker creates an extra section |
| <<COMMON>> for each input file's BFD to hold information about |
| common storage. |
| |
| The raw data is not necessarily read in when |
| the section descriptor is created. Some targets may leave the |
| data in place until a <<bfd_get_section_contents>> call is |
| made. Other back ends may read in all the data at once. For |
| example, an S-record file has to be read once to determine the |
| size of the data. An IEEE-695 file doesn't contain raw data in |
| sections, but data and relocation expressions intermixed, so |
| the data area has to be parsed to get out the data and |
| relocations. |
| |
| INODE |
| Section Output, typedef asection, Section Input, Sections |
| |
| SUBSECTION |
| Section output |
| |
| To write a new object style BFD, the various sections to be |
| written have to be created. They are attached to the BFD in |
| the same way as input sections; data is written to the |
| sections using <<bfd_set_section_contents>>. |
| |
| Any program that creates or combines sections (e.g., the assembler |
| and linker) must use the <<asection>> fields <<output_section>> and |
| <<output_offset>> to indicate the file sections to which each |
| section must be written. (If the section is being created from |
| scratch, <<output_section>> should probably point to the section |
| itself and <<output_offset>> should probably be zero.) |
| |
| The data to be written comes from input sections attached |
| (via <<output_section>> pointers) to |
| the output sections. The output section structure can be |
| considered a filter for the input section: the output section |
| determines the vma of the output data and the name, but the |
| input section determines the offset into the output section of |
| the data to be written. |
| |
| E.g., to create a section "O", starting at 0x100, 0x123 long, |
| containing two subsections, "A" at offset 0x0 (i.e., at vma |
| 0x100) and "B" at offset 0x20 (i.e., at vma 0x120) the <<asection>> |
| structures would look like: |
| |
| | section name "A" |
| | output_offset 0x00 |
| | size 0x20 |
| | output_section -----------> section name "O" |
| | | vma 0x100 |
| | section name "B" | size 0x123 |
| | output_offset 0x20 | |
| | size 0x103 | |
| | output_section --------| |
| |
| SUBSECTION |
| Link orders |
| |
| The data within a section is stored in a @dfn{link_order}. |
| These are much like the fixups in <<gas>>. The link_order |
| abstraction allows a section to grow and shrink within itself. |
| |
| A link_order knows how big it is, and which is the next |
| link_order and where the raw data for it is; it also points to |
| a list of relocations which apply to it. |
| |
| The link_order is used by the linker to perform relaxing on |
| final code. The compiler creates code which is as big as |
| necessary to make it work without relaxing, and the user can |
| select whether to relax. Sometimes relaxing takes a lot of |
| time. The linker runs around the relocations to see if any |
| are attached to data which can be shrunk, if so it does it on |
| a link_order by link_order basis. |
| |
| */ |
| |
| #include "bfd.h" |
| #include "sysdep.h" |
| #include "libbfd.h" |
| #include "bfdlink.h" |
| |
| /* |
| DOCDD |
| INODE |
| typedef asection, section prototypes, Section Output, Sections |
| SUBSECTION |
| typedef asection |
| |
| Here is the section structure: |
| |
| CODE_FRAGMENT |
| . |
| .{* This structure is used for a comdat section, as in PE. A comdat |
| . section is associated with a particular symbol. When the linker |
| . sees a comdat section, it keeps only one of the sections with a |
| . given name and associated with a given symbol. *} |
| . |
| .struct bfd_comdat_info |
| .{ |
| . {* The name of the symbol associated with a comdat section. *} |
| . const char *name; |
| . |
| . {* The local symbol table index of the symbol associated with a |
| . comdat section. This is only meaningful to the object file format |
| . specific code; it is not an index into the list returned by |
| . bfd_canonicalize_symtab. *} |
| . long symbol; |
| .}; |
| . |
| .typedef struct sec |
| .{ |
| . {* The name of the section; the name isn't a copy, the pointer is |
| . the same as that passed to bfd_make_section. *} |
| . const char *name; |
| . |
| . {* A unique sequence number. *} |
| . int id; |
| . |
| . {* Which section in the bfd; 0..n-1 as sections are created in a bfd. *} |
| . int index; |
| . |
| . {* The next section in the list belonging to the BFD, or NULL. *} |
| . struct sec *next; |
| . |
| . {* The field flags contains attributes of the section. Some |
| . flags are read in from the object file, and some are |
| . synthesized from other information. *} |
| . flagword flags; |
| . |
| .#define SEC_NO_FLAGS 0x000 |
| . |
| . {* Tells the OS to allocate space for this section when loading. |
| . This is clear for a section containing debug information only. *} |
| .#define SEC_ALLOC 0x001 |
| . |
| . {* Tells the OS to load the section from the file when loading. |
| . This is clear for a .bss section. *} |
| .#define SEC_LOAD 0x002 |
| . |
| . {* The section contains data still to be relocated, so there is |
| . some relocation information too. *} |
| .#define SEC_RELOC 0x004 |
| . |
| . {* ELF reserves 4 processor specific bits and 8 operating system |
| . specific bits in sh_flags; at present we can get away with just |
| . one in communicating between the assembler and BFD, but this |
| . isn't a good long-term solution. *} |
| .#define SEC_ARCH_BIT_0 0x008 |
| . |
| . {* A signal to the OS that the section contains read only data. *} |
| .#define SEC_READONLY 0x010 |
| . |
| . {* The section contains code only. *} |
| .#define SEC_CODE 0x020 |
| . |
| . {* The section contains data only. *} |
| .#define SEC_DATA 0x040 |
| . |
| . {* The section will reside in ROM. *} |
| .#define SEC_ROM 0x080 |
| . |
| . {* The section contains constructor information. This section |
| . type is used by the linker to create lists of constructors and |
| . destructors used by <<g++>>. When a back end sees a symbol |
| . which should be used in a constructor list, it creates a new |
| . section for the type of name (e.g., <<__CTOR_LIST__>>), attaches |
| . the symbol to it, and builds a relocation. To build the lists |
| . of constructors, all the linker has to do is catenate all the |
| . sections called <<__CTOR_LIST__>> and relocate the data |
| . contained within - exactly the operations it would peform on |
| . standard data. *} |
| .#define SEC_CONSTRUCTOR 0x100 |
| . |
| . {* The section has contents - a data section could be |
| . <<SEC_ALLOC>> | <<SEC_HAS_CONTENTS>>; a debug section could be |
| . <<SEC_HAS_CONTENTS>> *} |
| .#define SEC_HAS_CONTENTS 0x200 |
| . |
| . {* An instruction to the linker to not output the section |
| . even if it has information which would normally be written. *} |
| .#define SEC_NEVER_LOAD 0x400 |
| . |
| . {* The section is a COFF shared library section. This flag is |
| . only for the linker. If this type of section appears in |
| . the input file, the linker must copy it to the output file |
| . without changing the vma or size. FIXME: Although this |
| . was originally intended to be general, it really is COFF |
| . specific (and the flag was renamed to indicate this). It |
| . might be cleaner to have some more general mechanism to |
| . allow the back end to control what the linker does with |
| . sections. *} |
| .#define SEC_COFF_SHARED_LIBRARY 0x800 |
| . |
| . {* The section contains thread local data. *} |
| .#define SEC_THREAD_LOCAL 0x1000 |
| . |
| . {* The section has GOT references. This flag is only for the |
| . linker, and is currently only used by the elf32-hppa back end. |
| . It will be set if global offset table references were detected |
| . in this section, which indicate to the linker that the section |
| . contains PIC code, and must be handled specially when doing a |
| . static link. *} |
| .#define SEC_HAS_GOT_REF 0x4000 |
| . |
| . {* The section contains common symbols (symbols may be defined |
| . multiple times, the value of a symbol is the amount of |
| . space it requires, and the largest symbol value is the one |
| . used). Most targets have exactly one of these (which we |
| . translate to bfd_com_section_ptr), but ECOFF has two. *} |
| .#define SEC_IS_COMMON 0x8000 |
| . |
| . {* The section contains only debugging information. For |
| . example, this is set for ELF .debug and .stab sections. |
| . strip tests this flag to see if a section can be |
| . discarded. *} |
| .#define SEC_DEBUGGING 0x10000 |
| . |
| . {* The contents of this section are held in memory pointed to |
| . by the contents field. This is checked by bfd_get_section_contents, |
| . and the data is retrieved from memory if appropriate. *} |
| .#define SEC_IN_MEMORY 0x20000 |
| . |
| . {* The contents of this section are to be excluded by the |
| . linker for executable and shared objects unless those |
| . objects are to be further relocated. *} |
| .#define SEC_EXCLUDE 0x40000 |
| . |
| . {* The contents of this section are to be sorted based on the sum of |
| . the symbol and addend values specified by the associated relocation |
| . entries. Entries without associated relocation entries will be |
| . appended to the end of the section in an unspecified order. *} |
| .#define SEC_SORT_ENTRIES 0x80000 |
| . |
| . {* When linking, duplicate sections of the same name should be |
| . discarded, rather than being combined into a single section as |
| . is usually done. This is similar to how common symbols are |
| . handled. See SEC_LINK_DUPLICATES below. *} |
| .#define SEC_LINK_ONCE 0x100000 |
| . |
| . {* If SEC_LINK_ONCE is set, this bitfield describes how the linker |
| . should handle duplicate sections. *} |
| .#define SEC_LINK_DUPLICATES 0x600000 |
| . |
| . {* This value for SEC_LINK_DUPLICATES means that duplicate |
| . sections with the same name should simply be discarded. *} |
| .#define SEC_LINK_DUPLICATES_DISCARD 0x0 |
| . |
| . {* This value for SEC_LINK_DUPLICATES means that the linker |
| . should warn if there are any duplicate sections, although |
| . it should still only link one copy. *} |
| .#define SEC_LINK_DUPLICATES_ONE_ONLY 0x200000 |
| . |
| . {* This value for SEC_LINK_DUPLICATES means that the linker |
| . should warn if any duplicate sections are a different size. *} |
| .#define SEC_LINK_DUPLICATES_SAME_SIZE 0x400000 |
| . |
| . {* This value for SEC_LINK_DUPLICATES means that the linker |
| . should warn if any duplicate sections contain different |
| . contents. *} |
| .#define SEC_LINK_DUPLICATES_SAME_CONTENTS 0x600000 |
| . |
| . {* This section was created by the linker as part of dynamic |
| . relocation or other arcane processing. It is skipped when |
| . going through the first-pass output, trusting that someone |
| . else up the line will take care of it later. *} |
| .#define SEC_LINKER_CREATED 0x800000 |
| . |
| . {* This section should not be subject to garbage collection. *} |
| .#define SEC_KEEP 0x1000000 |
| . |
| . {* This section contains "short" data, and should be placed |
| . "near" the GP. *} |
| .#define SEC_SMALL_DATA 0x2000000 |
| . |
| . {* This section contains data which may be shared with other |
| . executables or shared objects. *} |
| .#define SEC_SHARED 0x4000000 |
| . |
| . {* When a section with this flag is being linked, then if the size of |
| . the input section is less than a page, it should not cross a page |
| . boundary. If the size of the input section is one page or more, it |
| . should be aligned on a page boundary. *} |
| .#define SEC_BLOCK 0x8000000 |
| . |
| . {* Conditionally link this section; do not link if there are no |
| . references found to any symbol in the section. *} |
| .#define SEC_CLINK 0x10000000 |
| . |
| . {* Attempt to merge identical entities in the section. |
| . Entity size is given in the entsize field. *} |
| .#define SEC_MERGE 0x20000000 |
| . |
| . {* If given with SEC_MERGE, entities to merge are zero terminated |
| . strings where entsize specifies character size instead of fixed |
| . size entries. *} |
| .#define SEC_STRINGS 0x40000000 |
| . |
| . {* This section contains data about section groups. *} |
| .#define SEC_GROUP 0x80000000 |
| . |
| . {* End of section flags. *} |
| . |
| . {* Some internal packed boolean fields. *} |
| . |
| . {* See the vma field. *} |
| . unsigned int user_set_vma : 1; |
| . |
| . {* Whether relocations have been processed. *} |
| . unsigned int reloc_done : 1; |
| . |
| . {* A mark flag used by some of the linker backends. *} |
| . unsigned int linker_mark : 1; |
| . |
| . {* Another mark flag used by some of the linker backends. Set for |
| . output sections that have an input section. *} |
| . unsigned int linker_has_input : 1; |
| . |
| . {* A mark flag used by some linker backends for garbage collection. *} |
| . unsigned int gc_mark : 1; |
| . |
| . {* Used by the ELF code to mark sections which have been allocated |
| . to segments. *} |
| . unsigned int segment_mark : 1; |
| . |
| . {* End of internal packed boolean fields. *} |
| . |
| . {* The virtual memory address of the section - where it will be |
| . at run time. The symbols are relocated against this. The |
| . user_set_vma flag is maintained by bfd; if it's not set, the |
| . backend can assign addresses (for example, in <<a.out>>, where |
| . the default address for <<.data>> is dependent on the specific |
| . target and various flags). *} |
| . bfd_vma vma; |
| . |
| . {* The load address of the section - where it would be in a |
| . rom image; really only used for writing section header |
| . information. *} |
| . bfd_vma lma; |
| . |
| . {* The size of the section in octets, as it will be output. |
| . Contains a value even if the section has no contents (e.g., the |
| . size of <<.bss>>). This will be filled in after relocation. *} |
| . bfd_size_type _cooked_size; |
| . |
| . {* The original size on disk of the section, in octets. Normally this |
| . value is the same as the size, but if some relaxing has |
| . been done, then this value will be bigger. *} |
| . bfd_size_type _raw_size; |
| . |
| . {* If this section is going to be output, then this value is the |
| . offset in *bytes* into the output section of the first byte in the |
| . input section (byte ==> smallest addressable unit on the |
| . target). In most cases, if this was going to start at the |
| . 100th octet (8-bit quantity) in the output section, this value |
| . would be 100. However, if the target byte size is 16 bits |
| . (bfd_octets_per_byte is "2"), this value would be 50. *} |
| . bfd_vma output_offset; |
| . |
| . {* The output section through which to map on output. *} |
| . struct sec *output_section; |
| . |
| . {* The alignment requirement of the section, as an exponent of 2 - |
| . e.g., 3 aligns to 2^3 (or 8). *} |
| . unsigned int alignment_power; |
| . |
| . {* If an input section, a pointer to a vector of relocation |
| . records for the data in this section. *} |
| . struct reloc_cache_entry *relocation; |
| . |
| . {* If an output section, a pointer to a vector of pointers to |
| . relocation records for the data in this section. *} |
| . struct reloc_cache_entry **orelocation; |
| . |
| . {* The number of relocation records in one of the above. *} |
| . unsigned reloc_count; |
| . |
| . {* Information below is back end specific - and not always used |
| . or updated. *} |
| . |
| . {* File position of section data. *} |
| . file_ptr filepos; |
| . |
| . {* File position of relocation info. *} |
| . file_ptr rel_filepos; |
| . |
| . {* File position of line data. *} |
| . file_ptr line_filepos; |
| . |
| . {* Pointer to data for applications. *} |
| . PTR userdata; |
| . |
| . {* If the SEC_IN_MEMORY flag is set, this points to the actual |
| . contents. *} |
| . unsigned char *contents; |
| . |
| . {* Attached line number information. *} |
| . alent *lineno; |
| . |
| . {* Number of line number records. *} |
| . unsigned int lineno_count; |
| . |
| . {* Entity size for merging purposes. *} |
| . unsigned int entsize; |
| . |
| . {* Optional information about a COMDAT entry; NULL if not COMDAT. *} |
| . struct bfd_comdat_info *comdat; |
| . |
| . {* When a section is being output, this value changes as more |
| . linenumbers are written out. *} |
| . file_ptr moving_line_filepos; |
| . |
| . {* What the section number is in the target world. *} |
| . int target_index; |
| . |
| . PTR used_by_bfd; |
| . |
| . {* If this is a constructor section then here is a list of the |
| . relocations created to relocate items within it. *} |
| . struct relent_chain *constructor_chain; |
| . |
| . {* The BFD which owns the section. *} |
| . bfd *owner; |
| . |
| . {* A symbol which points at this section only. *} |
| . struct symbol_cache_entry *symbol; |
| . struct symbol_cache_entry **symbol_ptr_ptr; |
| . |
| . struct bfd_link_order *link_order_head; |
| . struct bfd_link_order *link_order_tail; |
| .} asection; |
| . |
| .{* These sections are global, and are managed by BFD. The application |
| . and target back end are not permitted to change the values in |
| . these sections. New code should use the section_ptr macros rather |
| . than referring directly to the const sections. The const sections |
| . may eventually vanish. *} |
| .#define BFD_ABS_SECTION_NAME "*ABS*" |
| .#define BFD_UND_SECTION_NAME "*UND*" |
| .#define BFD_COM_SECTION_NAME "*COM*" |
| .#define BFD_IND_SECTION_NAME "*IND*" |
| . |
| .{* The absolute section. *} |
| .extern const asection bfd_abs_section; |
| .#define bfd_abs_section_ptr ((asection *) &bfd_abs_section) |
| .#define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr) |
| .{* Pointer to the undefined section. *} |
| .extern const asection bfd_und_section; |
| .#define bfd_und_section_ptr ((asection *) &bfd_und_section) |
| .#define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr) |
| .{* Pointer to the common section. *} |
| .extern const asection bfd_com_section; |
| .#define bfd_com_section_ptr ((asection *) &bfd_com_section) |
| .{* Pointer to the indirect section. *} |
| .extern const asection bfd_ind_section; |
| .#define bfd_ind_section_ptr ((asection *) &bfd_ind_section) |
| .#define bfd_is_ind_section(sec) ((sec) == bfd_ind_section_ptr) |
| . |
| .#define bfd_is_const_section(SEC) \ |
| . ( ((SEC) == bfd_abs_section_ptr) \ |
| . || ((SEC) == bfd_und_section_ptr) \ |
| . || ((SEC) == bfd_com_section_ptr) \ |
| . || ((SEC) == bfd_ind_section_ptr)) |
| . |
| .extern const struct symbol_cache_entry * const bfd_abs_symbol; |
| .extern const struct symbol_cache_entry * const bfd_com_symbol; |
| .extern const struct symbol_cache_entry * const bfd_und_symbol; |
| .extern const struct symbol_cache_entry * const bfd_ind_symbol; |
| .#define bfd_get_section_size_before_reloc(section) \ |
| . ((section)->reloc_done ? (abort (), (bfd_size_type) 1) \ |
| . : (section)->_raw_size) |
| .#define bfd_get_section_size_after_reloc(section) \ |
| . ((section)->reloc_done ? (section)->_cooked_size \ |
| . : (abort (), (bfd_size_type) 1)) |
| . |
| .{* Macros to handle insertion and deletion of a bfd's sections. These |
| . only handle the list pointers, ie. do not adjust section_count, |
| . target_index etc. *} |
| .#define bfd_section_list_remove(ABFD, PS) \ |
| . do \ |
| . { \ |
| . asection **_ps = PS; \ |
| . asection *_s = *_ps; \ |
| . *_ps = _s->next; \ |
| . if (_s->next == NULL) \ |
| . (ABFD)->section_tail = _ps; \ |
| . } \ |
| . while (0) |
| .#define bfd_section_list_insert(ABFD, PS, S) \ |
| . do \ |
| . { \ |
| . asection **_ps = PS; \ |
| . asection *_s = S; \ |
| . _s->next = *_ps; \ |
| . *_ps = _s; \ |
| . if (_s->next == NULL) \ |
| . (ABFD)->section_tail = &_s->next; \ |
| . } \ |
| . while (0) |
| . |
| */ |
| |
| /* We use a macro to initialize the static asymbol structures because |
| traditional C does not permit us to initialize a union member while |
| gcc warns if we don't initialize it. */ |
| /* the_bfd, name, value, attr, section [, udata] */ |
| #ifdef __STDC__ |
| #define GLOBAL_SYM_INIT(NAME, SECTION) \ |
| { 0, NAME, 0, BSF_SECTION_SYM, (asection *) SECTION, { 0 }} |
| #else |
| #define GLOBAL_SYM_INIT(NAME, SECTION) \ |
| { 0, NAME, 0, BSF_SECTION_SYM, (asection *) SECTION } |
| #endif |
| |
| /* These symbols are global, not specific to any BFD. Therefore, anything |
| that tries to change them is broken, and should be repaired. */ |
| |
| static const asymbol global_syms[] = |
| { |
| GLOBAL_SYM_INIT (BFD_COM_SECTION_NAME, &bfd_com_section), |
| GLOBAL_SYM_INIT (BFD_UND_SECTION_NAME, &bfd_und_section), |
| GLOBAL_SYM_INIT (BFD_ABS_SECTION_NAME, &bfd_abs_section), |
| GLOBAL_SYM_INIT (BFD_IND_SECTION_NAME, &bfd_ind_section) |
| }; |
| |
| #define STD_SECTION(SEC, FLAGS, SYM, NAME, IDX) \ |
| const asymbol * const SYM = (asymbol *) &global_syms[IDX]; \ |
| const asection SEC = \ |
| /* name, id, index, next, flags, user_set_vma, reloc_done, */ \ |
| { NAME, IDX, 0, NULL, FLAGS, 0, 0, \ |
| \ |
| /* linker_mark, linker_has_input, gc_mark, segment_mark, */ \ |
| 0, 0, 1, 0, \ |
| \ |
| /* vma, lma, _cooked_size, _raw_size, */ \ |
| 0, 0, 0, 0, \ |
| \ |
| /* output_offset, output_section, alignment_power, */ \ |
| 0, (struct sec *) &SEC, 0, \ |
| \ |
| /* relocation, orelocation, reloc_count, filepos, rel_filepos, */ \ |
| NULL, NULL, 0, 0, 0, \ |
| \ |
| /* line_filepos, userdata, contents, lineno, lineno_count, */ \ |
| 0, NULL, NULL, NULL, 0, \ |
| \ |
| /* entsize, comdat, moving_line_filepos, */ \ |
| 0, NULL, 0, \ |
| \ |
| /* target_index, used_by_bfd, constructor_chain, owner, */ \ |
| 0, NULL, NULL, NULL, \ |
| \ |
| /* symbol, */ \ |
| (struct symbol_cache_entry *) &global_syms[IDX], \ |
| \ |
| /* symbol_ptr_ptr, */ \ |
| (struct symbol_cache_entry **) &SYM, \ |
| \ |
| /* link_order_head, link_order_tail */ \ |
| NULL, NULL \ |
| } |
| |
| STD_SECTION (bfd_com_section, SEC_IS_COMMON, bfd_com_symbol, |
| BFD_COM_SECTION_NAME, 0); |
| STD_SECTION (bfd_und_section, 0, bfd_und_symbol, BFD_UND_SECTION_NAME, 1); |
| STD_SECTION (bfd_abs_section, 0, bfd_abs_symbol, BFD_ABS_SECTION_NAME, 2); |
| STD_SECTION (bfd_ind_section, 0, bfd_ind_symbol, BFD_IND_SECTION_NAME, 3); |
| #undef STD_SECTION |
| |
| struct section_hash_entry |
| { |
| struct bfd_hash_entry root; |
| asection section; |
| }; |
| |
| /* Initialize an entry in the section hash table. */ |
| |
| struct bfd_hash_entry * |
| bfd_section_hash_newfunc (entry, table, string) |
| struct bfd_hash_entry *entry; |
| struct bfd_hash_table *table; |
| const char *string; |
| { |
| /* Allocate the structure if it has not already been allocated by a |
| subclass. */ |
| if (entry == NULL) |
| { |
| entry = (struct bfd_hash_entry *) |
| bfd_hash_allocate (table, sizeof (struct section_hash_entry)); |
| if (entry == NULL) |
| return entry; |
| } |
| |
| /* Call the allocation method of the superclass. */ |
| entry = bfd_hash_newfunc (entry, table, string); |
| if (entry != NULL) |
| { |
| memset ((PTR) &((struct section_hash_entry *) entry)->section, |
| 0, sizeof (asection)); |
| } |
| |
| return entry; |
| } |
| |
| #define section_hash_lookup(table, string, create, copy) \ |
| ((struct section_hash_entry *) \ |
| bfd_hash_lookup ((table), (string), (create), (copy))) |
| |
| /* Initializes a new section. NEWSECT->NAME is already set. */ |
| |
| static asection *bfd_section_init PARAMS ((bfd *, asection *)); |
| |
| static asection * |
| bfd_section_init (abfd, newsect) |
| bfd *abfd; |
| asection *newsect; |
| { |
| static int section_id = 0x10; /* id 0 to 3 used by STD_SECTION. */ |
| |
| newsect->id = section_id; |
| newsect->index = abfd->section_count; |
| newsect->owner = abfd; |
| |
| /* Create a symbol whose only job is to point to this section. This |
| is useful for things like relocs which are relative to the base |
| of a section. */ |
| newsect->symbol = bfd_make_empty_symbol (abfd); |
| if (newsect->symbol == NULL) |
| return NULL; |
| |
| newsect->symbol->name = newsect->name; |
| newsect->symbol->value = 0; |
| newsect->symbol->section = newsect; |
| newsect->symbol->flags = BSF_SECTION_SYM; |
| |
| newsect->symbol_ptr_ptr = &newsect->symbol; |
| |
| if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect))) |
| return NULL; |
| |
| section_id++; |
| abfd->section_count++; |
| *abfd->section_tail = newsect; |
| abfd->section_tail = &newsect->next; |
| return newsect; |
| } |
| |
| /* |
| DOCDD |
| INODE |
| section prototypes, , typedef asection, Sections |
| SUBSECTION |
| Section prototypes |
| |
| These are the functions exported by the section handling part of BFD. |
| */ |
| |
| /* |
| FUNCTION |
| bfd_section_list_clear |
| |
| SYNOPSIS |
| void bfd_section_list_clear (bfd *); |
| |
| DESCRIPTION |
| Clears the section list, and also resets the section count and |
| hash table entries. |
| */ |
| |
| void |
| bfd_section_list_clear (abfd) |
| bfd *abfd; |
| { |
| abfd->sections = NULL; |
| abfd->section_tail = &abfd->sections; |
| abfd->section_count = 0; |
| memset ((PTR) abfd->section_htab.table, 0, |
| abfd->section_htab.size * sizeof (struct bfd_hash_entry *)); |
| } |
| |
| /* |
| FUNCTION |
| bfd_get_section_by_name |
| |
| SYNOPSIS |
| asection *bfd_get_section_by_name(bfd *abfd, const char *name); |
| |
| DESCRIPTION |
| Run through @var{abfd} and return the one of the |
| <<asection>>s whose name matches @var{name}, otherwise <<NULL>>. |
| @xref{Sections}, for more information. |
| |
| This should only be used in special cases; the normal way to process |
| all sections of a given name is to use <<bfd_map_over_sections>> and |
| <<strcmp>> on the name (or better yet, base it on the section flags |
| or something else) for each section. |
| */ |
| |
| asection * |
| bfd_get_section_by_name (abfd, name) |
| bfd *abfd; |
| const char *name; |
| { |
| struct section_hash_entry *sh; |
| |
| sh = section_hash_lookup (&abfd->section_htab, name, FALSE, FALSE); |
| if (sh != NULL) |
| return &sh->section; |
| |
| return NULL; |
| } |
| |
| /* |
| FUNCTION |
| bfd_get_unique_section_name |
| |
| SYNOPSIS |
| char *bfd_get_unique_section_name(bfd *abfd, |
| const char *templat, |
| int *count); |
| |
| DESCRIPTION |
| Invent a section name that is unique in @var{abfd} by tacking |
| a dot and a digit suffix onto the original @var{templat}. If |
| @var{count} is non-NULL, then it specifies the first number |
| tried as a suffix to generate a unique name. The value |
| pointed to by @var{count} will be incremented in this case. |
| */ |
| |
| char * |
| bfd_get_unique_section_name (abfd, templat, count) |
| bfd *abfd; |
| const char *templat; |
| int *count; |
| { |
| int num; |
| unsigned int len; |
| char *sname; |
| |
| len = strlen (templat); |
| sname = bfd_malloc ((bfd_size_type) len + 8); |
| if (sname == NULL) |
| return NULL; |
| memcpy (sname, templat, len); |
| num = 1; |
| if (count != NULL) |
| num = *count; |
| |
| do |
| { |
| /* If we have a million sections, something is badly wrong. */ |
| if (num > 999999) |
| abort (); |
| sprintf (sname + len, ".%d", num++); |
| } |
| while (section_hash_lookup (&abfd->section_htab, sname, FALSE, FALSE)); |
| |
| if (count != NULL) |
| *count = num; |
| return sname; |
| } |
| |
| /* |
| FUNCTION |
| bfd_make_section_old_way |
| |
| SYNOPSIS |
| asection *bfd_make_section_old_way(bfd *abfd, const char *name); |
| |
| DESCRIPTION |
| Create a new empty section called @var{name} |
| and attach it to the end of the chain of sections for the |
| BFD @var{abfd}. An attempt to create a section with a name which |
| is already in use returns its pointer without changing the |
| section chain. |
| |
| It has the funny name since this is the way it used to be |
| before it was rewritten.... |
| |
| Possible errors are: |
| o <<bfd_error_invalid_operation>> - |
| If output has already started for this BFD. |
| o <<bfd_error_no_memory>> - |
| If memory allocation fails. |
| |
| */ |
| |
| asection * |
| bfd_make_section_old_way (abfd, name) |
| bfd *abfd; |
| const char *name; |
| { |
| struct section_hash_entry *sh; |
| asection *newsect; |
| |
| if (abfd->output_has_begun) |
| { |
| bfd_set_error (bfd_error_invalid_operation); |
| return NULL; |
| } |
| |
| if (strcmp (name, BFD_ABS_SECTION_NAME) == 0) |
| return bfd_abs_section_ptr; |
| |
| if (strcmp (name, BFD_COM_SECTION_NAME) == 0) |
| return bfd_com_section_ptr; |
| |
| if (strcmp (name, BFD_UND_SECTION_NAME) == 0) |
| return bfd_und_section_ptr; |
| |
| if (strcmp (name, BFD_IND_SECTION_NAME) == 0) |
| return bfd_ind_section_ptr; |
| |
| sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE); |
| if (sh == NULL) |
| return NULL; |
| |
| newsect = &sh->section; |
| if (newsect->name != NULL) |
| { |
| /* Section already exists. */ |
| return newsect; |
| } |
| |
| newsect->name = name; |
| return bfd_section_init (abfd, newsect); |
| } |
| |
| /* |
| FUNCTION |
| bfd_make_section_anyway |
| |
| SYNOPSIS |
| asection *bfd_make_section_anyway(bfd *abfd, const char *name); |
| |
| DESCRIPTION |
| Create a new empty section called @var{name} and attach it to the end of |
| the chain of sections for @var{abfd}. Create a new section even if there |
| is already a section with that name. |
| |
| Return <<NULL>> and set <<bfd_error>> on error; possible errors are: |
| o <<bfd_error_invalid_operation>> - If output has already started for @var{abfd}. |
| o <<bfd_error_no_memory>> - If memory allocation fails. |
| */ |
| |
| sec_ptr |
| bfd_make_section_anyway (abfd, name) |
| bfd *abfd; |
| const char *name; |
| { |
| struct section_hash_entry *sh; |
| asection *newsect; |
| |
| if (abfd->output_has_begun) |
| { |
| bfd_set_error (bfd_error_invalid_operation); |
| return NULL; |
| } |
| |
| sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE); |
| if (sh == NULL) |
| return NULL; |
| |
| newsect = &sh->section; |
| if (newsect->name != NULL) |
| { |
| /* We are making a section of the same name. It can't go in |
| section_htab without generating a unique section name and |
| that would be pointless; We don't need to traverse the |
| hash table. */ |
| newsect = (asection *) bfd_zalloc (abfd, sizeof (asection)); |
| if (newsect == NULL) |
| return NULL; |
| } |
| |
| newsect->name = name; |
| return bfd_section_init (abfd, newsect); |
| } |
| |
| /* |
| FUNCTION |
| bfd_make_section |
| |
| SYNOPSIS |
| asection *bfd_make_section(bfd *, const char *name); |
| |
| DESCRIPTION |
| Like <<bfd_make_section_anyway>>, but return <<NULL>> (without calling |
| bfd_set_error ()) without changing the section chain if there is already a |
| section named @var{name}. If there is an error, return <<NULL>> and set |
| <<bfd_error>>. |
| */ |
| |
| asection * |
| bfd_make_section (abfd, name) |
| bfd *abfd; |
| const char *name; |
| { |
| struct section_hash_entry *sh; |
| asection *newsect; |
| |
| if (abfd->output_has_begun) |
| { |
| bfd_set_error (bfd_error_invalid_operation); |
| return NULL; |
| } |
| |
| if (strcmp (name, BFD_ABS_SECTION_NAME) == 0 |
| || strcmp (name, BFD_COM_SECTION_NAME) == 0 |
| || strcmp (name, BFD_UND_SECTION_NAME) == 0 |
| || strcmp (name, BFD_IND_SECTION_NAME) == 0) |
| return NULL; |
| |
| sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE); |
| if (sh == NULL) |
| return NULL; |
| |
| newsect = &sh->section; |
| if (newsect->name != NULL) |
| { |
| /* Section already exists. */ |
| return newsect; |
| } |
| |
| newsect->name = name; |
| return bfd_section_init (abfd, newsect); |
| } |
| |
| /* |
| FUNCTION |
| bfd_set_section_flags |
| |
| SYNOPSIS |
| bfd_boolean bfd_set_section_flags (bfd *abfd, asection *sec, flagword flags); |
| |
| DESCRIPTION |
| Set the attributes of the section @var{sec} in the BFD |
| @var{abfd} to the value @var{flags}. Return <<TRUE>> on success, |
| <<FALSE>> on error. Possible error returns are: |
| |
| o <<bfd_error_invalid_operation>> - |
| The section cannot have one or more of the attributes |
| requested. For example, a .bss section in <<a.out>> may not |
| have the <<SEC_HAS_CONTENTS>> field set. |
| |
| */ |
| |
| /*ARGSUSED*/ |
| bfd_boolean |
| bfd_set_section_flags (abfd, section, flags) |
| bfd *abfd ATTRIBUTE_UNUSED; |
| sec_ptr section; |
| flagword flags; |
| { |
| #if 0 |
| /* If you try to copy a text section from an input file (where it |
| has the SEC_CODE flag set) to an output file, this loses big if |
| the bfd_applicable_section_flags (abfd) doesn't have the SEC_CODE |
| set - which it doesn't, at least not for a.out. FIXME */ |
| |
| if ((flags & bfd_applicable_section_flags (abfd)) != flags) |
| { |
| bfd_set_error (bfd_error_invalid_operation); |
| return FALSE; |
| } |
| #endif |
| |
| section->flags = flags; |
| return TRUE; |
| } |
| |
| /* |
| FUNCTION |
| bfd_map_over_sections |
| |
| SYNOPSIS |
| void bfd_map_over_sections(bfd *abfd, |
| void (*func) (bfd *abfd, |
| asection *sect, |
| PTR obj), |
| PTR obj); |
| |
| DESCRIPTION |
| Call the provided function @var{func} for each section |
| attached to the BFD @var{abfd}, passing @var{obj} as an |
| argument. The function will be called as if by |
| |
| | func(abfd, the_section, obj); |
| |
| This is the prefered method for iterating over sections; an |
| alternative would be to use a loop: |
| |
| | section *p; |
| | for (p = abfd->sections; p != NULL; p = p->next) |
| | func(abfd, p, ...) |
| |
| */ |
| |
| /*VARARGS2*/ |
| void |
| bfd_map_over_sections (abfd, operation, user_storage) |
| bfd *abfd; |
| void (*operation) PARAMS ((bfd * abfd, asection * sect, PTR obj)); |
| PTR user_storage; |
| { |
| asection *sect; |
| unsigned int i = 0; |
| |
| for (sect = abfd->sections; sect != NULL; i++, sect = sect->next) |
| (*operation) (abfd, sect, user_storage); |
| |
| if (i != abfd->section_count) /* Debugging */ |
| abort (); |
| } |
| |
| /* |
| FUNCTION |
| bfd_set_section_size |
| |
| SYNOPSIS |
| bfd_boolean bfd_set_section_size (bfd *abfd, asection *sec, bfd_size_type val); |
| |
| DESCRIPTION |
| Set @var{sec} to the size @var{val}. If the operation is |
| ok, then <<TRUE>> is returned, else <<FALSE>>. |
| |
| Possible error returns: |
| o <<bfd_error_invalid_operation>> - |
| Writing has started to the BFD, so setting the size is invalid. |
| |
| */ |
| |
| bfd_boolean |
| bfd_set_section_size (abfd, ptr, val) |
| bfd *abfd; |
| sec_ptr ptr; |
| bfd_size_type val; |
| { |
| /* Once you've started writing to any section you cannot create or change |
| the size of any others. */ |
| |
| if (abfd->output_has_begun) |
| { |
| bfd_set_error (bfd_error_invalid_operation); |
| return FALSE; |
| } |
| |
| ptr->_cooked_size = val; |
| ptr->_raw_size = val; |
| |
| return TRUE; |
| } |
| |
| /* |
| FUNCTION |
| bfd_set_section_contents |
| |
| SYNOPSIS |
| bfd_boolean bfd_set_section_contents (bfd *abfd, asection *section, |
| PTR data, file_ptr offset, |
| bfd_size_type count); |
| |
| DESCRIPTION |
| Sets the contents of the section @var{section} in BFD |
| @var{abfd} to the data starting in memory at @var{data}. The |
| data is written to the output section starting at offset |
| @var{offset} for @var{count} octets. |
| |
| Normally <<TRUE>> is returned, else <<FALSE>>. Possible error |
| returns are: |
| o <<bfd_error_no_contents>> - |
| The output section does not have the <<SEC_HAS_CONTENTS>> |
| attribute, so nothing can be written to it. |
| o and some more too |
| |
| This routine is front end to the back end function |
| <<_bfd_set_section_contents>>. |
| |
| */ |
| |
| #define bfd_get_section_size_now(abfd,sec) \ |
| (sec->reloc_done \ |
| ? bfd_get_section_size_after_reloc (sec) \ |
| : bfd_get_section_size_before_reloc (sec)) |
| |
| bfd_boolean |
| bfd_set_section_contents (abfd, section, location, offset, count) |
| bfd *abfd; |
| sec_ptr section; |
| PTR location; |
| file_ptr offset; |
| bfd_size_type count; |
| { |
| bfd_size_type sz; |
| |
| if (!(bfd_get_section_flags (abfd, section) & SEC_HAS_CONTENTS)) |
| { |
| bfd_set_error (bfd_error_no_contents); |
| return FALSE; |
| } |
| |
| sz = bfd_get_section_size_now (abfd, section); |
| if ((bfd_size_type) offset > sz |
| || count > sz |
| || offset + count > sz |
| || count != (size_t) count) |
| { |
| bfd_set_error (bfd_error_bad_value); |
| return FALSE; |
| } |
| |
| switch (abfd->direction) |
| { |
| case read_direction: |
| case no_direction: |
| bfd_set_error (bfd_error_invalid_operation); |
| return FALSE; |
| |
| case write_direction: |
| break; |
| |
| case both_direction: |
| /* File is opened for update. `output_has_begun' some time ago when |
| the file was created. Do not recompute sections sizes or alignments |
| in _bfd_set_section_content. */ |
| abfd->output_has_begun = TRUE; |
| break; |
| } |
| |
| /* Record a copy of the data in memory if desired. */ |
| if (section->contents |
| && location != (PTR) (section->contents + offset)) |
| memcpy (section->contents + offset, location, (size_t) count); |
| |
| if (BFD_SEND (abfd, _bfd_set_section_contents, |
| (abfd, section, location, offset, count))) |
| { |
| abfd->output_has_begun = TRUE; |
| return TRUE; |
| } |
| |
| return FALSE; |
| } |
| |
| /* |
| FUNCTION |
| bfd_get_section_contents |
| |
| SYNOPSIS |
| bfd_boolean bfd_get_section_contents (bfd *abfd, asection *section, |
| PTR location, file_ptr offset, |
| bfd_size_type count); |
| |
| DESCRIPTION |
| Read data from @var{section} in BFD @var{abfd} |
| into memory starting at @var{location}. The data is read at an |
| offset of @var{offset} from the start of the input section, |
| and is read for @var{count} bytes. |
| |
| If the contents of a constructor with the <<SEC_CONSTRUCTOR>> |
| flag set are requested or if the section does not have the |
| <<SEC_HAS_CONTENTS>> flag set, then the @var{location} is filled |
| with zeroes. If no errors occur, <<TRUE>> is returned, else |
| <<FALSE>>. |
| |
| */ |
| bfd_boolean |
| bfd_get_section_contents (abfd, section, location, offset, count) |
| bfd *abfd; |
| sec_ptr section; |
| PTR location; |
| file_ptr offset; |
| bfd_size_type count; |
| { |
| bfd_size_type sz; |
| |
| if (section->flags & SEC_CONSTRUCTOR) |
| { |
| memset (location, 0, (size_t) count); |
| return TRUE; |
| } |
| |
| /* Even if reloc_done is TRUE, this function reads unrelocated |
| contents, so we want the raw size. */ |
| sz = section->_raw_size; |
| if ((bfd_size_type) offset > sz |
| || count > sz |
| || offset + count > sz |
| || count != (size_t) count) |
| { |
| bfd_set_error (bfd_error_bad_value); |
| return FALSE; |
| } |
| |
| if (count == 0) |
| /* Don't bother. */ |
| return TRUE; |
| |
| if ((section->flags & SEC_HAS_CONTENTS) == 0) |
| { |
| memset (location, 0, (size_t) count); |
| return TRUE; |
| } |
| |
| if ((section->flags & SEC_IN_MEMORY) != 0) |
| { |
| memcpy (location, section->contents + offset, (size_t) count); |
| return TRUE; |
| } |
| |
| return BFD_SEND (abfd, _bfd_get_section_contents, |
| (abfd, section, location, offset, count)); |
| } |
| |
| /* |
| FUNCTION |
| bfd_copy_private_section_data |
| |
| SYNOPSIS |
| bfd_boolean bfd_copy_private_section_data (bfd *ibfd, asection *isec, |
| bfd *obfd, asection *osec); |
| |
| DESCRIPTION |
| Copy private section information from @var{isec} in the BFD |
| @var{ibfd} to the section @var{osec} in the BFD @var{obfd}. |
| Return <<TRUE>> on success, <<FALSE>> on error. Possible error |
| returns are: |
| |
| o <<bfd_error_no_memory>> - |
| Not enough memory exists to create private data for @var{osec}. |
| |
| .#define bfd_copy_private_section_data(ibfd, isection, obfd, osection) \ |
| . BFD_SEND (obfd, _bfd_copy_private_section_data, \ |
| . (ibfd, isection, obfd, osection)) |
| */ |
| |
| /* |
| FUNCTION |
| _bfd_strip_section_from_output |
| |
| SYNOPSIS |
| void _bfd_strip_section_from_output |
| (struct bfd_link_info *info, asection *section); |
| |
| DESCRIPTION |
| Remove @var{section} from the output. If the output section |
| becomes empty, remove it from the output bfd. |
| |
| This function won't actually do anything except twiddle flags |
| if called too late in the linking process, when it's not safe |
| to remove sections. |
| */ |
| void |
| _bfd_strip_section_from_output (info, s) |
| struct bfd_link_info *info; |
| asection *s; |
| { |
| asection *os; |
| asection *is; |
| bfd *abfd; |
| |
| s->flags |= SEC_EXCLUDE; |
| |
| /* If the section wasn't assigned to an output section, or the |
| section has been discarded by the linker script, there's nothing |
| more to do. */ |
| os = s->output_section; |
| if (os == NULL || os->owner == NULL) |
| return; |
| |
| /* If the output section has other (non-excluded) input sections, we |
| can't remove it. */ |
| for (abfd = info->input_bfds; abfd != NULL; abfd = abfd->link_next) |
| for (is = abfd->sections; is != NULL; is = is->next) |
| if (is->output_section == os && (is->flags & SEC_EXCLUDE) == 0) |
| return; |
| |
| /* If the output section is empty, flag it for removal too. |
| See ldlang.c:strip_excluded_output_sections for the action. */ |
| os->flags |= SEC_EXCLUDE; |
| } |
| |
| /* |
| FUNCTION |
| bfd_generic_discard_group |
| |
| SYNOPSIS |
| bfd_boolean bfd_generic_discard_group (bfd *abfd, asection *group); |
| |
| DESCRIPTION |
| Remove all members of @var{group} from the output. |
| */ |
| |
| bfd_boolean |
| bfd_generic_discard_group (abfd, group) |
| bfd *abfd ATTRIBUTE_UNUSED; |
| asection *group ATTRIBUTE_UNUSED; |
| { |
| return TRUE; |
| } |