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Diffstat (limited to 'binutils-2.25/bfd/section.c')
| -rw-r--r-- | binutils-2.25/bfd/section.c | 1633 |
1 files changed, 1633 insertions, 0 deletions
diff --git a/binutils-2.25/bfd/section.c b/binutils-2.25/bfd/section.c new file mode 100644 index 00000000..fb19d8cc --- /dev/null +++ b/binutils-2.25/bfd/section.c @@ -0,0 +1,1633 @@ +/* Object file "section" support for the BFD library. + Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, + 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, + 2012, 2013 + 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 3 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., 51 Franklin Street - Fifth Floor, Boston, + MA 02110-1301, 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 "sysdep.h" +#include "bfd.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 +. +.typedef struct bfd_section +.{ +. {* 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 bfd_section *next; +. +. {* The previous section in the list belonging to the BFD, or NULL. *} +. struct bfd_section *prev; +. +. {* 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 +. +. {* A signal to the OS that the section contains read only data. *} +.#define SEC_READONLY 0x008 +. +. {* The section contains code only. *} +.#define SEC_CODE 0x010 +. +. {* The section contains data only. *} +.#define SEC_DATA 0x020 +. +. {* The section will reside in ROM. *} +.#define SEC_ROM 0x040 +. +. {* 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 0x080 +. +. {* 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 0x100 +. +. {* An instruction to the linker to not output the section +. even if it has information which would normally be written. *} +.#define SEC_NEVER_LOAD 0x200 +. +. {* The section contains thread local data. *} +.#define SEC_THREAD_LOCAL 0x400 +. +. {* 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 0x800 +. +. {* 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 0x1000 +. +. {* 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 0x2000 +. +. {* 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 0x4000 +. +. {* 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 0x8000 +. +. {* 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 0x10000 +. +. {* 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 0x20000 +. +. {* If SEC_LINK_ONCE is set, this bitfield describes how the linker +. should handle duplicate sections. *} +.#define SEC_LINK_DUPLICATES 0xc0000 +. +. {* 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 0x40000 +. +. {* 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 0x80000 +. +. {* 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 \ +. (SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE) +. +. {* 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 0x100000 +. +. {* This section should not be subject to garbage collection. +. Also set to inform the linker that this section should not be +. listed in the link map as discarded. *} +.#define SEC_KEEP 0x200000 +. +. {* This section contains "short" data, and should be placed +. "near" the GP. *} +.#define SEC_SMALL_DATA 0x400000 +. +. {* Attempt to merge identical entities in the section. +. Entity size is given in the entsize field. *} +.#define SEC_MERGE 0x800000 +. +. {* 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 0x1000000 +. +. {* This section contains data about section groups. *} +.#define SEC_GROUP 0x2000000 +. +. {* 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 0x4000000 +. +. {* This input section should be copied to output in reverse order +. as an array of pointers. This is for ELF linker internal use +. only. *} +.#define SEC_ELF_REVERSE_COPY 0x4000000 +. +. {* This section contains data which may be shared with other +. executables or shared objects. This is for COFF only. *} +.#define SEC_COFF_SHARED 0x8000000 +. +. {* 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. This is for TI +. TMS320C54X only. *} +.#define SEC_TIC54X_BLOCK 0x10000000 +. +. {* Conditionally link this section; do not link if there are no +. references found to any symbol in the section. This is for TI +. TMS320C54X only. *} +.#define SEC_TIC54X_CLINK 0x20000000 +. +. {* Indicate that section has the no read flag set. This happens +. when memory read flag isn't set. *} +.#define SEC_COFF_NOREAD 0x40000000 +. +. {* End of section flags. *} +. +. {* Some internal packed boolean fields. *} +. +. {* See the vma field. *} +. unsigned int user_set_vma : 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; +. +. {* Mark flag used by some linker backends for garbage collection. *} +. unsigned int gc_mark : 1; +. +. {* Section compression status. *} +. unsigned int compress_status : 2; +.#define COMPRESS_SECTION_NONE 0 +.#define COMPRESS_SECTION_DONE 1 +.#define DECOMPRESS_SECTION_SIZED 2 +. +. {* The following flags are used by the ELF linker. *} +. +. {* Mark sections which have been allocated to segments. *} +. unsigned int segment_mark : 1; +. +. {* Type of sec_info information. *} +. unsigned int sec_info_type:3; +.#define SEC_INFO_TYPE_NONE 0 +.#define SEC_INFO_TYPE_STABS 1 +.#define SEC_INFO_TYPE_MERGE 2 +.#define SEC_INFO_TYPE_EH_FRAME 3 +.#define SEC_INFO_TYPE_JUST_SYMS 4 +. +. {* Nonzero if this section uses RELA relocations, rather than REL. *} +. unsigned int use_rela_p:1; +. +. {* Bits used by various backends. The generic code doesn't touch +. these fields. *} +. +. unsigned int sec_flg0:1; +. unsigned int sec_flg1:1; +. unsigned int sec_flg2:1; +. unsigned int sec_flg3:1; +. unsigned int sec_flg4:1; +. unsigned int sec_flg5:1; +. +. {* 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>>). *} +. bfd_size_type size; +. +. {* For input sections, the original size on disk of the section, in +. octets. This field should be set for any section whose size is +. changed by linker relaxation. It is required for sections where +. the linker relaxation scheme doesn't cache altered section and +. reloc contents (stabs, eh_frame, SEC_MERGE, some coff relaxing +. targets), and thus the original size needs to be kept to read the +. section multiple times. For output sections, rawsize holds the +. section size calculated on a previous linker relaxation pass. *} +. bfd_size_type rawsize; +. +. {* The compressed size of the section in octets. *} +. bfd_size_type compressed_size; +. +. {* Relaxation table. *} +. struct relax_table *relax; +. +. {* Count of used relaxation table entries. *} +. int relax_count; +. +. +. {* 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 bfd_section *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. *} +. void *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; +. +. {* Points to the kept section if this section is a link-once section, +. and is discarded. *} +. struct bfd_section *kept_section; +. +. {* 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; +. +. void *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 bfd_symbol *symbol; +. struct bfd_symbol **symbol_ptr_ptr; +. +. {* Early in the link process, map_head and map_tail are used to build +. a list of input sections attached to an output section. Later, +. output sections use these fields for a list of bfd_link_order +. structs. *} +. union { +. struct bfd_link_order *link_order; +. struct bfd_section *s; +. } map_head, map_tail; +.} asection; +. +.{* Relax table contains information about instructions which can +. be removed by relaxation -- replacing a long address with a +. short address. *} +.struct relax_table { +. {* Address where bytes may be deleted. *} +. bfd_vma addr; +. +. {* Number of bytes to be deleted. *} +. int size; +.}; +. +.{* 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. *} +.extern asection _bfd_std_section[4]; +. +.#define BFD_ABS_SECTION_NAME "*ABS*" +.#define BFD_UND_SECTION_NAME "*UND*" +.#define BFD_COM_SECTION_NAME "*COM*" +.#define BFD_IND_SECTION_NAME "*IND*" +. +.{* Pointer to the common section. *} +.#define bfd_com_section_ptr (&_bfd_std_section[0]) +.{* Pointer to the undefined section. *} +.#define bfd_und_section_ptr (&_bfd_std_section[1]) +.{* Pointer to the absolute section. *} +.#define bfd_abs_section_ptr (&_bfd_std_section[2]) +.{* Pointer to the indirect section. *} +.#define bfd_ind_section_ptr (&_bfd_std_section[3]) +. +.#define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr) +.#define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr) +.#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)) +. +.{* 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, S) \ +. do \ +. { \ +. asection *_s = S; \ +. asection *_next = _s->next; \ +. asection *_prev = _s->prev; \ +. if (_prev) \ +. _prev->next = _next; \ +. else \ +. (ABFD)->sections = _next; \ +. if (_next) \ +. _next->prev = _prev; \ +. else \ +. (ABFD)->section_last = _prev; \ +. } \ +. while (0) +.#define bfd_section_list_append(ABFD, S) \ +. do \ +. { \ +. asection *_s = S; \ +. bfd *_abfd = ABFD; \ +. _s->next = NULL; \ +. if (_abfd->section_last) \ +. { \ +. _s->prev = _abfd->section_last; \ +. _abfd->section_last->next = _s; \ +. } \ +. else \ +. { \ +. _s->prev = NULL; \ +. _abfd->sections = _s; \ +. } \ +. _abfd->section_last = _s; \ +. } \ +. while (0) +.#define bfd_section_list_prepend(ABFD, S) \ +. do \ +. { \ +. asection *_s = S; \ +. bfd *_abfd = ABFD; \ +. _s->prev = NULL; \ +. if (_abfd->sections) \ +. { \ +. _s->next = _abfd->sections; \ +. _abfd->sections->prev = _s; \ +. } \ +. else \ +. { \ +. _s->next = NULL; \ +. _abfd->section_last = _s; \ +. } \ +. _abfd->sections = _s; \ +. } \ +. while (0) +.#define bfd_section_list_insert_after(ABFD, A, S) \ +. do \ +. { \ +. asection *_a = A; \ +. asection *_s = S; \ +. asection *_next = _a->next; \ +. _s->next = _next; \ +. _s->prev = _a; \ +. _a->next = _s; \ +. if (_next) \ +. _next->prev = _s; \ +. else \ +. (ABFD)->section_last = _s; \ +. } \ +. while (0) +.#define bfd_section_list_insert_before(ABFD, B, S) \ +. do \ +. { \ +. asection *_b = B; \ +. asection *_s = S; \ +. asection *_prev = _b->prev; \ +. _s->prev = _prev; \ +. _s->next = _b; \ +. _b->prev = _s; \ +. if (_prev) \ +. _prev->next = _s; \ +. else \ +. (ABFD)->sections = _s; \ +. } \ +. while (0) +.#define bfd_section_removed_from_list(ABFD, S) \ +. ((S)->next == NULL ? (ABFD)->section_last != (S) : (S)->next->prev != (S)) +. +.#define BFD_FAKE_SECTION(SEC, FLAGS, SYM, NAME, IDX) \ +. {* name, id, index, next, prev, flags, user_set_vma, *} \ +. { NAME, IDX, 0, NULL, NULL, FLAGS, 0, \ +. \ +. {* linker_mark, linker_has_input, gc_mark, decompress_status, *} \ +. 0, 0, 1, 0, \ +. \ +. {* segment_mark, sec_info_type, use_rela_p, *} \ +. 0, 0, 0, \ +. \ +. {* sec_flg0, sec_flg1, sec_flg2, sec_flg3, sec_flg4, sec_flg5, *} \ +. 0, 0, 0, 0, 0, 0, \ +. \ +. {* vma, lma, size, rawsize, compressed_size, relax, relax_count, *} \ +. 0, 0, 0, 0, 0, 0, 0, \ +. \ +. {* output_offset, output_section, alignment_power, *} \ +. 0, &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, kept_section, moving_line_filepos, *} \ +. 0, NULL, 0, \ +. \ +. {* target_index, used_by_bfd, constructor_chain, owner, *} \ +. 0, NULL, NULL, NULL, \ +. \ +. {* symbol, symbol_ptr_ptr, *} \ +. (struct bfd_symbol *) SYM, &SEC.symbol, \ +. \ +. {* map_head, map_tail *} \ +. { NULL }, { NULL } \ +. } +. +*/ + +/* 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, SECTION, { 0 }} +#else +#define GLOBAL_SYM_INIT(NAME, SECTION) \ + { 0, NAME, 0, BSF_SECTION_SYM, 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_ptr), + GLOBAL_SYM_INIT (BFD_UND_SECTION_NAME, bfd_und_section_ptr), + GLOBAL_SYM_INIT (BFD_ABS_SECTION_NAME, bfd_abs_section_ptr), + GLOBAL_SYM_INIT (BFD_IND_SECTION_NAME, bfd_ind_section_ptr) +}; + +#define STD_SECTION(NAME, IDX, FLAGS) \ + BFD_FAKE_SECTION(_bfd_std_section[IDX], FLAGS, &global_syms[IDX], NAME, IDX) + +asection _bfd_std_section[] = { + STD_SECTION (BFD_COM_SECTION_NAME, 0, SEC_IS_COMMON), + STD_SECTION (BFD_UND_SECTION_NAME, 1, 0), + STD_SECTION (BFD_ABS_SECTION_NAME, 2, 0), + STD_SECTION (BFD_IND_SECTION_NAME, 3, 0) +}; +#undef STD_SECTION + +/* Initialize an entry in the section hash table. */ + +struct bfd_hash_entry * +bfd_section_hash_newfunc (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 (&((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))) + +/* 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. */ + +bfd_boolean +_bfd_generic_new_section_hook (bfd *abfd, asection *newsect) +{ + newsect->symbol = bfd_make_empty_symbol (abfd); + if (newsect->symbol == NULL) + return FALSE; + + 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; + return TRUE; +} + +/* Initializes a new section. NEWSECT->NAME is already set. */ + +static asection * +bfd_section_init (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; + + if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect))) + return NULL; + + section_id++; + abfd->section_count++; + bfd_section_list_append (abfd, newsect); + 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 (bfd *abfd) +{ + abfd->sections = NULL; + abfd->section_last = NULL; + abfd->section_count = 0; + memset (abfd->section_htab.table, 0, + abfd->section_htab.size * sizeof (struct bfd_hash_entry *)); + abfd->section_htab.count = 0; +} + +/* +FUNCTION + bfd_get_section_by_name + +SYNOPSIS + asection *bfd_get_section_by_name (bfd *abfd, const char *name); + +DESCRIPTION + Return the most recently created section attached to @var{abfd} + named @var{name}. Return NULL if no such section exists. +*/ + +asection * +bfd_get_section_by_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_next_section_by_name + +SYNOPSIS + asection *bfd_get_next_section_by_name (asection *sec); + +DESCRIPTION + Given @var{sec} is a section returned by @code{bfd_get_section_by_name}, + return the next most recently created section attached to the same + BFD with the same name. Return NULL if no such section exists. +*/ + +asection * +bfd_get_next_section_by_name (asection *sec) +{ + struct section_hash_entry *sh; + const char *name; + unsigned long hash; + + sh = ((struct section_hash_entry *) + ((char *) sec - offsetof (struct section_hash_entry, section))); + + hash = sh->root.hash; + name = sec->name; + for (sh = (struct section_hash_entry *) sh->root.next; + sh != NULL; + sh = (struct section_hash_entry *) sh->root.next) + if (sh->root.hash == hash + && strcmp (sh->root.string, name) == 0) + return &sh->section; + + return NULL; +} + +/* +FUNCTION + bfd_get_linker_section + +SYNOPSIS + asection *bfd_get_linker_section (bfd *abfd, const char *name); + +DESCRIPTION + Return the linker created section attached to @var{abfd} + named @var{name}. Return NULL if no such section exists. +*/ + +asection * +bfd_get_linker_section (bfd *abfd, const char *name) +{ + asection *sec = bfd_get_section_by_name (abfd, name); + + while (sec != NULL && (sec->flags & SEC_LINKER_CREATED) == 0) + sec = bfd_get_next_section_by_name (sec); + return sec; +} + +/* +FUNCTION + bfd_get_section_by_name_if + +SYNOPSIS + asection *bfd_get_section_by_name_if + (bfd *abfd, + const char *name, + bfd_boolean (*func) (bfd *abfd, asection *sect, void *obj), + void *obj); + +DESCRIPTION + Call the provided function @var{func} for each section + attached to the BFD @var{abfd} whose name matches @var{name}, + passing @var{obj} as an argument. The function will be called + as if by + +| func (abfd, the_section, obj); + + It returns the first section for which @var{func} returns true, + otherwise <<NULL>>. + +*/ + +asection * +bfd_get_section_by_name_if (bfd *abfd, const char *name, + bfd_boolean (*operation) (bfd *, + asection *, + void *), + void *user_storage) +{ + struct section_hash_entry *sh; + unsigned long hash; + + sh = section_hash_lookup (&abfd->section_htab, name, FALSE, FALSE); + if (sh == NULL) + return NULL; + + hash = sh->root.hash; + do + { + if ((*operation) (abfd, &sh->section, user_storage)) + return &sh->section; + sh = (struct section_hash_entry *) sh->root.next; + } + while (sh != NULL && sh->root.hash == hash + && strcmp (sh->root.string, name) == 0); + + 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 (bfd *abfd, const char *templat, int *count) +{ + int num; + unsigned int len; + char *sname; + + len = strlen (templat); + sname = (char *) bfd_malloc (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 (bfd *abfd, const char *name) +{ + asection *newsect; + + if (abfd->output_has_begun) + { + bfd_set_error (bfd_error_invalid_operation); + return NULL; + } + + if (strcmp (name, BFD_ABS_SECTION_NAME) == 0) + newsect = bfd_abs_section_ptr; + else if (strcmp (name, BFD_COM_SECTION_NAME) == 0) + newsect = bfd_com_section_ptr; + else if (strcmp (name, BFD_UND_SECTION_NAME) == 0) + newsect = bfd_und_section_ptr; + else if (strcmp (name, BFD_IND_SECTION_NAME) == 0) + newsect = bfd_ind_section_ptr; + else + { + struct section_hash_entry *sh; + + 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); + } + + /* Call new_section_hook when "creating" the standard abs, com, und + and ind sections to tack on format specific section data. + Also, create a proper section symbol. */ + if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect))) + return NULL; + return newsect; +} + +/* +FUNCTION + bfd_make_section_anyway_with_flags + +SYNOPSIS + asection *bfd_make_section_anyway_with_flags + (bfd *abfd, const char *name, flagword flags); + +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. Also set the attributes of the + new section to the value @var{flags}. + + 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_with_flags (bfd *abfd, const char *name, + flagword flags) +{ + 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. Put it in the + section hash table. Even though we can't find it directly by a + hash lookup, we'll be able to find the section by traversing + sh->root.next quicker than looking at all the bfd sections. */ + struct section_hash_entry *new_sh; + new_sh = (struct section_hash_entry *) + bfd_section_hash_newfunc (NULL, &abfd->section_htab, name); + if (new_sh == NULL) + return NULL; + + new_sh->root = sh->root; + sh->root.next = &new_sh->root; + newsect = &new_sh->section; + } + + newsect->flags = flags; + 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 (bfd *abfd, const char *name) +{ + return bfd_make_section_anyway_with_flags (abfd, name, 0); +} + +/* +FUNCTION + bfd_make_section_with_flags + +SYNOPSIS + asection *bfd_make_section_with_flags + (bfd *, const char *name, flagword flags); + +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}. Also set the attributes of the new section to + the value @var{flags}. If there is an error, return <<NULL>> and set + <<bfd_error>>. +*/ + +asection * +bfd_make_section_with_flags (bfd *abfd, const char *name, + flagword flags) +{ + 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 NULL; + } + + newsect->name = name; + newsect->flags = flags; + 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 (bfd *abfd, const char *name) +{ + return bfd_make_section_with_flags (abfd, name, 0); +} + +/* +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. + +*/ + +bfd_boolean +bfd_set_section_flags (bfd *abfd ATTRIBUTE_UNUSED, + sec_ptr section, + flagword flags) +{ + section->flags = flags; + return TRUE; +} + +/* +FUNCTION + bfd_rename_section + +SYNOPSIS + void bfd_rename_section + (bfd *abfd, asection *sec, const char *newname); + +DESCRIPTION + Rename section @var{sec} in @var{abfd} to @var{newname}. +*/ + +void +bfd_rename_section (bfd *abfd, sec_ptr sec, const char *newname) +{ + struct section_hash_entry *sh; + + sh = (struct section_hash_entry *) + ((char *) sec - offsetof (struct section_hash_entry, section)); + sh->section.name = newname; + bfd_hash_rename (&abfd->section_htab, newname, &sh->root); +} + +/* +FUNCTION + bfd_map_over_sections + +SYNOPSIS + void bfd_map_over_sections + (bfd *abfd, + void (*func) (bfd *abfd, asection *sect, void *obj), + void *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 preferred method for iterating over sections; an + alternative would be to use a loop: + +| asection *p; +| for (p = abfd->sections; p != NULL; p = p->next) +| func (abfd, p, ...) + +*/ + +void +bfd_map_over_sections (bfd *abfd, + void (*operation) (bfd *, asection *, void *), + void *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_sections_find_if + +SYNOPSIS + asection *bfd_sections_find_if + (bfd *abfd, + bfd_boolean (*operation) (bfd *abfd, asection *sect, void *obj), + void *obj); + +DESCRIPTION + Call the provided function @var{operation} for each section + attached to the BFD @var{abfd}, passing @var{obj} as an + argument. The function will be called as if by + +| operation (abfd, the_section, obj); + + It returns the first section for which @var{operation} returns true. + +*/ + +asection * +bfd_sections_find_if (bfd *abfd, + bfd_boolean (*operation) (bfd *, asection *, void *), + void *user_storage) +{ + asection *sect; + + for (sect = abfd->sections; sect != NULL; sect = sect->next) + if ((*operation) (abfd, sect, user_storage)) + break; + + return sect; +} + +/* +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 (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->size = val; + return TRUE; +} + +/* +FUNCTION + bfd_set_section_contents + +SYNOPSIS + bfd_boolean bfd_set_section_contents + (bfd *abfd, asection *section, const void *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>>. + +*/ + +bfd_boolean +bfd_set_section_contents (bfd *abfd, + sec_ptr section, + const void *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 = section->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 (!bfd_write_p (abfd)) + { + bfd_set_error (bfd_error_invalid_operation); + return FALSE; + } + + /* Record a copy of the data in memory if desired. */ + if (section->contents + && location != 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, void *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 (bfd *abfd, + sec_ptr section, + void *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; + } + + if (abfd->direction != write_direction && section->rawsize != 0) + sz = section->rawsize; + else + sz = section->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) + { + if (section->contents == NULL) + { + /* This can happen because of errors earlier on in the linking process. + We do not want to seg-fault here, so clear the flag and return an + error code. */ + section->flags &= ~ SEC_IN_MEMORY; + bfd_set_error (bfd_error_invalid_operation); + return FALSE; + } + + memmove (location, section->contents + offset, (size_t) count); + return TRUE; + } + + return BFD_SEND (abfd, _bfd_get_section_contents, + (abfd, section, location, offset, count)); +} + +/* +FUNCTION + bfd_malloc_and_get_section + +SYNOPSIS + bfd_boolean bfd_malloc_and_get_section + (bfd *abfd, asection *section, bfd_byte **buf); + +DESCRIPTION + Read all data from @var{section} in BFD @var{abfd} + into a buffer, *@var{buf}, malloc'd by this function. +*/ + +bfd_boolean +bfd_malloc_and_get_section (bfd *abfd, sec_ptr sec, bfd_byte **buf) +{ + *buf = NULL; + return bfd_get_full_section_contents (abfd, sec, buf); +} +/* +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_generic_is_group_section + +SYNOPSIS + bfd_boolean bfd_generic_is_group_section (bfd *, const asection *sec); + +DESCRIPTION + Returns TRUE if @var{sec} is a member of a group. +*/ + +bfd_boolean +bfd_generic_is_group_section (bfd *abfd ATTRIBUTE_UNUSED, + const asection *sec ATTRIBUTE_UNUSED) +{ + return FALSE; +} + +/* +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 (bfd *abfd ATTRIBUTE_UNUSED, + asection *group ATTRIBUTE_UNUSED) +{ + return TRUE; +} |