X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=bfd%2Fsection.c;h=3b9c095ac6d3c5c6f2ad566c7b27b1b8d0b92a27;hb=c188b0bec3b;hp=ab3bb51627e8999440868ca6602d213f42ab0510;hpb=4a96bc044aadaa2cfc17ba5149c8599dddd0a9ae;p=deliverable%2Fbinutils-gdb.git diff --git a/bfd/section.c b/bfd/section.c index ab3bb51627..3b9c095ac6 100644 --- a/bfd/section.c +++ b/bfd/section.c @@ -1,5 +1,5 @@ /* Object file "section" support for the BFD library. - Copyright (C) 1990-1991 Free Software Foundation, Inc. + Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc. Written by Cygnus Support. This file is part of BFD, the Binary File Descriptor library. @@ -22,23 +22,22 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ SECTION Sections - Sections are supported in BFD in <>. - The raw data contained within a BFD is maintained through the section abstraction. A single BFD may have any number of - sections, and keeps hold of them by pointing to the first, + 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 <>. + @menu -* Section Input:: -* Section Output:: -* typedef asection:: -* section prototypes:: +@* Section Input:: +@* Section Output:: +@* typedef asection:: +@* section prototypes:: @end menu INODE - Section Input, Section Output, Sections, Sections - +Section Input, Section Output, Sections, Sections SUBSECTION Section Input @@ -46,52 +45,60 @@ SUBSECTION created and attached to the BFD. Each section has a name which describes the section in the - outside world - for example, <> would contain at least + outside world---for example, <> would contain at least three sections, called <<.text>>, <<.data>> and <<.bss>>. - Sometimes a BFD will contain more than the 'natural' number of + 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 a supernumary section + <>) to the sections attached to an already open + BFD. For example, the linker creates an extra section <> for each input file's BFD to hold information about common storage. - The raw data is not necessarily read in at the same time as + The raw data is not necessarily read in when the section descriptor is created. Some targets may leave the data in place until a <> 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 + 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 +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 + the same way as input sections; data is written to the sections using <>. - The linker uses the fields <> and - <> to create an output file. + Any program that creates or combines sections (e.g., the assembler + and linker) must use the <> fields <> and + <> to indicate the file sections to which each + section must be written. (If the section is being created from + scratch, <> should probably point to the section + itself and <> should probably be zero.) - The data to be written comes from input sections attached to + The data to be written comes from input sections attached + (via <> pointers) to the output sections. The output section structure can be - considered a filter for the input section, the output section + 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. - Eg to create a section "O", starting at 0x100, 0x123 long, - containing two subsections, "A" at offset 0x0 (ie at vma - 0x100) and "B" at offset 0x20 (ie at vma 0x120) the structures - would look like: + 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 <> + structures would look like: | section name "A" | output_offset 0x00 @@ -104,6 +111,25 @@ SUBSECTION | output_section --------| +SUBSECTION + Seclets + + The data within a section is stored in a <>. These + are much like the fixups in <>. The seclet abstraction + allows a section to grow and shrink within itself. + + A seclet knows how big it is, and which is the next seclet and + where the raw data for it is; it also points to a list of + relocations which apply to it. + + The seclet 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 seclet by seclet basis. + */ @@ -111,31 +137,34 @@ SUBSECTION #include "sysdep.h" #include "libbfd.h" + /* +DOCDD INODE - typedef asection, section prototypes, Section Output, Sections -SUBSECTION - typedef asection - +typedef asection, section prototypes, Section Output, Sections SUBSECTION typedef asection - The shape of a section struct: + Here is the section structure: CODE_FRAGMENT . .typedef struct sec .{ -. {* The name of the section, the name isn't a copy, the pointer is +. {* 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; . +. {* Which section is it; 0..nth. *} +. +. 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 of +. {* The field flags contains attributes of the section. Some . flags are read in from the object file, and some are . synthesized from other information. *} . @@ -143,91 +172,114 @@ CODE_FRAGMENT . .#define SEC_NO_FLAGS 0x000 . -. {* Tells the OS to allocate space for this section when loaded. -. This would clear for a section containing debug information +. {* 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 would be clear for a .bss section *} -. +. This is clear for a .bss section. *} .#define SEC_LOAD 0x002 -. {* The section contains data still to be relocated, so there will -. be some relocation information too. *} . +. {* The section contains data still to be relocated, so there is +. some relocation information too. *} .#define SEC_RELOC 0x004 . -. {* Obsolete ? *} -. +.#if 0 {* Obsolete ? *} .#define SEC_BALIGN 0x008 +.#endif . . {* 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 +.#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 <>. 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 (eg <<__CTOR_LIST__>>), attaches -. the symbol to it and builds a relocation. To build the lists -. of constructors, all the linker has to to is catenate all the -. sections called <<__CTOR_LIST__>> and relocte the data +. 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 is a constuctor, and should be placed at the -. end of the . *} -. -. +. end of the text, data, or bss section(?). *} .#define SEC_CONSTRUCTOR_TEXT 0x1100 -. .#define SEC_CONSTRUCTOR_DATA 0x2100 -. .#define SEC_CONSTRUCTOR_BSS 0x3100 . -. -. {* The section has contents - a bss section could be -. <> | <>, a debug section could be +. {* The section has contents - a data section could be +. <> | <>; a debug section could be . <> *} -. .#define SEC_HAS_CONTENTS 0x200 . -. {* An instruction to the linker not to output sections -. containing this flag even if they have information which -. would normally be written. *} -. +. {* 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 base address of the section in the address space of the -. target. *} -. +. {* The section is a shared library section. The linker must leave +. these completely alone, as the vma and size are used when +. the executable is loaded. *} +.#define SEC_SHARED_LIBRARY 0x800 +. +. {* The section is a common section (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), 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 +. +. {* End of section flags. *} +. +. {* 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 <>, where +. the default address for <<.data>> is dependent on the specific +. target and various flags). *} +. . bfd_vma vma; +. boolean user_set_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 bytes, 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 *} . -. {* The size of the section in bytes of the loaded section. This -. contains a value even if the section has no contents (eg, the -. size of <<.bss>>). *} +. bfd_size_type _cooked_size; . -. bfd_size_type size; +. {* The original size on disk of the section, in bytes. 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 into the output section of the first byte in the input -. section. Eg, if this was going to start at the 100th byte in +. section. E.g., if this was going to start at the 100th byte in . the output section, this value would be 100. *} . . bfd_vma output_offset; @@ -236,8 +288,8 @@ CODE_FRAGMENT . . struct sec *output_section; . -. {* The alignment requirement of the section, as an exponent - eg -. 3 aligns to 2^3 (or 8) *} +. {* The alignment requirement of the section, as an exponent of 2 - +. e.g., 3 aligns to 2^3 (or 8). *} . . unsigned int alignment_power; . @@ -255,14 +307,10 @@ CODE_FRAGMENT . . unsigned reloc_count; . -. {* Which section is it 0.nth *} -. -. int index; -. . {* Information below is back end specific - and not always used -. or updated +. or updated. *} . -. File position of section data *} +. {* File position of section data *} . . file_ptr filepos; . @@ -293,9 +341,9 @@ CODE_FRAGMENT . . file_ptr moving_line_filepos; . -. {* what the section number is in the target world *} +. {* What the section number is in the target world *} . -. unsigned int target_index; +. int target_index; . . PTR used_by_bfd; . @@ -308,18 +356,74 @@ CODE_FRAGMENT . . bfd *owner; . +. boolean reloc_done; +. {* A symbol which points at this section only *} +. struct symbol_cache_entry *symbol; +. struct symbol_cache_entry **symbol_ptr_ptr; +. +. struct bfd_seclet *seclets_head; +. struct bfd_seclet *seclets_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. *} +.#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 asection bfd_abs_section; +. {* Pointer to the undefined section *} +.extern asection bfd_und_section; +. {* Pointer to the common section *} +.extern asection bfd_com_section; +. {* Pointer to the indirect section *} +.extern asection bfd_ind_section; +. +.extern struct symbol_cache_entry *bfd_abs_symbol; +.extern struct symbol_cache_entry *bfd_com_symbol; +.extern struct symbol_cache_entry *bfd_und_symbol; +.extern struct symbol_cache_entry *bfd_ind_symbol; +.#define bfd_get_section_size_before_reloc(section) \ +. (section->reloc_done ? (abort(),1): (section)->_raw_size) +.#define bfd_get_section_size_after_reloc(section) \ +. ((section->reloc_done) ? (section)->_cooked_size: (abort(),1)) */ +/* 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[] = { + /* the_bfd, name, value, attr, section [, udata] */ + { 0, BFD_COM_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_com_section }, + { 0, BFD_UND_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_und_section }, + { 0, BFD_ABS_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_abs_section }, + { 0, BFD_IND_SECTION_NAME, 0, BSF_SECTION_SYM, &bfd_ind_section }, +}; + +#define STD_SECTION(SEC, FLAGS, SYM, NAME, IDX) \ + asymbol *SYM = (asymbol *) &global_syms[IDX]; \ + asection SEC = { NAME, 0, 0, FLAGS, 0, 0, (boolean) 0, 0, 0, 0, &SEC,\ + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (boolean) 0, \ + (asymbol *) &global_syms[IDX], &SYM, } + +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 + /* +DOCDD INODE - section prototypes, , typedef asection, Sections - +section prototypes, , typedef asection, Sections SUBSECTION section prototypes These are the functions exported by the section handling part of -<. +<>. */ /* @@ -330,10 +434,14 @@ SYNOPSIS asection *bfd_get_section_by_name(bfd *abfd, CONST char *name); DESCRIPTION - Runs through the provided @var{abfd} and returns the - <> who's name matches that provided, otherwise NULL. + Run through the provided @var{abfd} and return the one of the + <>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 * @@ -354,22 +462,22 @@ FUNCTION bfd_make_section_old_way SYNOPSIS - asection *bfd_make_section_old_way(bfd *, CONST char *name); + asection *bfd_make_section_old_way(bfd *abfd, CONST char *name); DESCRIPTION - This function creates a new empty section called @var{name} - and attaches it to the end of the chain of sections for the - BFD supplied. An attempt to create a section with a name which + 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 is was rewritten... + before it was rewritten.... Possible errors are: - o invalid_operation + o invalid_operation - If output has already started for this BFD. - o no_memory + o no_memory - If obstack alloc fails. */ @@ -388,44 +496,39 @@ DEFUN(bfd_make_section_old_way,(abfd, name), return sec; } - /* FUNCTION - bfd_make_section + bfd_make_section_anyway SYNOPSIS - asection * bfd_make_section(bfd *, CONST char *name); + asection *bfd_make_section_anyway(bfd *abfd, CONST char *name); DESCRIPTION - This function creates a new empty section called @var{name} - and attaches it to the end of the chain of sections for the - BFD supplied. An attempt to create a section with a name which - is already in use, returns NULL without changing the section - chain. + 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. - Possible errors are: - o invalid_operation - If output has already started for this BFD. - o no_memory - If obstack alloc fails. + Returns NULL and sets bfd_error on error; possible errors are: + o invalid_operation - If output has already started for @var{abfd}. + o no_memory - If obstack alloc fails. */ - - sec_ptr -DEFUN(bfd_make_section,(abfd, name), - bfd *abfd AND - CONST char * name) +bfd_make_section_anyway (abfd, name) + bfd *abfd; + CONST char *name; { - asection *newsect; - asection ** prev = &abfd->sections; + asection *newsect; + asection **prev = &abfd->sections; asection * sect = abfd->sections; - - if (abfd->output_has_begun) { - bfd_error = invalid_operation; - return NULL; - } + + if (abfd->output_has_begun) + { + bfd_error = invalid_operation; + return NULL; + } while (sect) { - if (!strcmp(sect->name, name)) return NULL; prev = §->next; sect = sect->next; } @@ -446,6 +549,18 @@ DEFUN(bfd_make_section,(abfd, name), newsect->reloc_count = 0; newsect->line_filepos =0; newsect->owner = abfd; + + /* Create a symbol whos 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); + newsect->symbol->name = 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)) != true) { free (newsect); return NULL; @@ -455,20 +570,68 @@ DEFUN(bfd_make_section,(abfd, name), return newsect; } +/* +FUNCTION + bfd_make_section + +SYNOPSIS + asection *bfd_make_section(bfd *, CONST char *name); + +DESCRIPTION + Like <>, but return NULL (without setting + bfd_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. +*/ + +sec_ptr +DEFUN(bfd_make_section,(abfd, name), + bfd *abfd AND + CONST char * name) +{ + asection * sect = abfd->sections; + + if (strcmp(name, BFD_ABS_SECTION_NAME) == 0) + { + return &bfd_abs_section; + } + if (strcmp(name, BFD_COM_SECTION_NAME) == 0) + { + return &bfd_com_section; + } + if (strcmp(name, BFD_UND_SECTION_NAME) == 0) + { + return &bfd_und_section; + } + + if (strcmp(name, BFD_IND_SECTION_NAME) == 0) + { + return &bfd_ind_section; + } + + while (sect) { + if (!strcmp(sect->name, name)) return NULL; + sect = sect->next; + } + + /* The name is not already used; go ahead and make a new section. */ + return bfd_make_section_anyway (abfd, name); +} + /* FUNCTION bfd_set_section_flags SYNOPSIS - boolean bfd_set_section_flags(bfd *, asection *, flagword); + boolean bfd_set_section_flags(bfd *abfd, asection *sec, flagword flags); DESCRIPTION - Attempts to set the attributes of the section named in the BFD - supplied to the value. Returns true on success, false on - error. Possible error returns are: + Set the attributes of the section @var{sec} in the BFD + @var{abfd} to the value @var{flags}. Returns <> on success, + <> on error. Possible error returns are: - o invalid operation + o invalid operation - The section cannot have one or more of the attributes requested. For example, a .bss section in <> may not have the <> field set. @@ -481,10 +644,17 @@ DEFUN(bfd_set_section_flags,(abfd, section, flags), sec_ptr section AND 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_error = invalid_operation; return false; } +#endif section->flags = flags; return true; @@ -496,16 +666,20 @@ FUNCTION bfd_map_over_sections SYNOPSIS - void bfd_map_over_sections(bfd *abfd, void (*func)(), PTR obj); + void bfd_map_over_sections(bfd *abfd, + void (*func)(bfd *abfd, + asection *sect, + PTR obj), + PTR obj); DESCRIPTION - Calls the provided function @var{func} for each section + 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 + This is the prefered method for iterating over sections; an alternative would be to use a loop: | section *p; @@ -519,7 +693,7 @@ DESCRIPTION void DEFUN(bfd_map_over_sections,(abfd, operation, user_storage), bfd *abfd AND - void (*operation)() AND + void (*operation) PARAMS ((bfd *abfd, asection *sect, PTR obj)) AND PTR user_storage) { asection *sect; @@ -538,14 +712,14 @@ FUNCTION bfd_set_section_size SYNOPSIS - boolean bfd_set_section_size(bfd *, asection *, bfd_size_type val); + boolean bfd_set_section_size(bfd *abfd, asection *sec, bfd_size_type val); DESCRIPTION - Sets @var{section} to the size @var{val}. If the operation is + Set @var{sec} to the size @var{val}. If the operation is ok, then <> is returned, else <>. Possible error returns: - o invalid_operation + o invalid_operation - Writing has started to the BFD, so setting the size is invalid */ @@ -564,7 +738,8 @@ DEFUN(bfd_set_section_size,(abfd, ptr, val), return false; } - ptr->size = val; + ptr->_cooked_size = val; + ptr->_raw_size = val; return true; } @@ -588,9 +763,11 @@ DESCRIPTION data is written to the output section starting at offset @var{offset} for @var{count} bytes. + + Normally <> is returned, else <>. Possible error returns are: - o no_contents + o no_contents - The output section does not have the <> attribute, so nothing can be written to it. o and some more too @@ -601,6 +778,11 @@ DESCRIPTION */ +#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)) + boolean DEFUN(bfd_set_section_contents,(abfd, section, location, offset, count), bfd *abfd AND @@ -609,11 +791,43 @@ DEFUN(bfd_set_section_contents,(abfd, section, location, offset, count), file_ptr offset AND bfd_size_type count) { - if (!(bfd_get_section_flags(abfd, section) & SEC_HAS_CONTENTS)) + bfd_size_type sz; + + if (!bfd_get_section_flags(abfd, section) & SEC_HAS_CONTENTS) { bfd_error = no_contents; return(false); - } + } + + if (offset < 0) + { + bad_val: + bfd_error = bad_value; + return false; + } + sz = bfd_get_section_size_now (abfd, section); + if (offset > sz + || count > sz + || offset + count > sz) + goto bad_val; + + switch (abfd->direction) + { + case read_direction: + case no_direction: + 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; + } if (BFD_SEND (abfd, _bfd_set_section_contents, (abfd, section, location, offset, count))) @@ -635,7 +849,7 @@ SYNOPSIS file_ptr offset, bfd_size_type count); DESCRIPTION - This function reads data from @var{section} in BFD @var{abfd} + 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. @@ -656,15 +870,30 @@ DEFUN(bfd_get_section_contents,(abfd, section, location, offset, count), file_ptr offset AND bfd_size_type count) { + bfd_size_type sz; + if (section->flags & SEC_CONSTRUCTOR) - { - memset(location, 0, (unsigned)count); - return true; - } - else - { - return (BFD_SEND (abfd, _bfd_get_section_contents, - (abfd, section, location, offset, count))); - } -} + { + memset(location, 0, (unsigned)count); + return true; + } + if (offset < 0) + { + bad_val: + bfd_error = bad_value; + return false; + } + sz = bfd_get_section_size_now (abfd, section); + if (offset > sz + || count > sz + || offset + count > sz) + goto bad_val; + + if (count == 0) + /* Don't bother. */ + return true; + + return BFD_SEND (abfd, _bfd_get_section_contents, + (abfd, section, location, offset, count)); +}