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/* GDB routines for manipulating objfiles. Copyright 1992, 1993, 1994, 1995 Free Software Foundation, Inc. Contributed by Cygnus Support, using pieces from other GDB modules. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* This file contains support routines for creating, manipulating, and destroying objfile structures. */ #include "defs.h" #ifdef NeXT #include <SegmentManager.h> #import <objc/zone.h> #else #include "bfd.h" /* Binary File Description */ #endif /* NeXT */ #include "symtab.h" #include "symfile.h" #include "objfiles.h" #include "gdb-stabs.h" #include "target.h" #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <obstack.h> /* Prototypes for local functions */ #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) static int open_existing_mapped_file PARAMS ((char *, long, int)); static int open_mapped_file PARAMS ((char *filename, long mtime, int mapped)); static CORE_ADDR map_to_address PARAMS ((void)); #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ /* Message to be printed before the error message, when an error occurs. */ extern char *error_pre_print; /* Externally visible variables that are owned by this module. See declarations in objfile.h for more info. */ struct objfile *object_files; /* Linked list of all objfiles */ struct objfile *current_objfile; /* For symbol file being read in */ struct objfile *symfile_objfile; /* Main symbol table loaded from */ struct objfile *rt_common_objfile; /* For runtime common symbols */ int mapped_symbol_files; /* Try to use mapped symbol files */ #ifndef DONT_USE_BFD /* Locate all mappable sections of a BFD file. objfile_p_char is a char * to get it through bfd_map_over_sections; we cast it back to its proper type. */ static void add_to_objfile_sections (abfd, asect, objfile_p_char) bfd *abfd; sec_ptr asect; PTR objfile_p_char; { struct objfile *objfile = (struct objfile *) objfile_p_char; struct obj_section section; flagword aflag; aflag = bfd_get_section_flags (abfd, asect); if (!(aflag & SEC_ALLOC)) return; if (0 == bfd_section_size (abfd, asect)) return; section.offset = 0; section.objfile = objfile; section.the_bfd_section = asect; section.addr = bfd_section_vma (abfd, asect); section.endaddr = section.addr + bfd_section_size (abfd, asect); obstack_grow (&objfile->psymbol_obstack, §ion, sizeof(section)); objfile->sections_end = (struct obj_section *) (((unsigned long) objfile->sections_end) + 1); } /* Builds a section table for OBJFILE. Returns 0 if OK, 1 on error (in which case bfd_error contains the error). */ int build_objfile_section_table (objfile) struct objfile *objfile; { /* objfile->sections can be already set when reading a mapped symbol file. I believe that we do need to rebuild the section table in this case (we rebuild other things derived from the bfd), but we can't free the old one (it's in the psymbol_obstack). So we just waste some memory. */ objfile->sections_end = 0; bfd_map_over_sections (objfile->obfd, add_to_objfile_sections, (char *)objfile); objfile->sections = (struct obj_section *) obstack_finish (&objfile->psymbol_obstack); objfile->sections_end = objfile->sections + (unsigned long) objfile->sections_end; return(0); } #endif /* DONT_USE_BFD */ /* Given a pointer to an initialized bfd (ABFD) and a flag that indicates whether or not an objfile is to be mapped (MAPPED), allocate a new objfile struct, fill it in as best we can, link it into the list of all known objfiles, and return a pointer to the new objfile struct. */ #ifdef NeXT struct objfile *allocate_objfile(void *manager, int mapped) #else struct objfile * allocate_objfile (abfd, mapped) bfd *abfd; int mapped; #endif /* NeXT */ { struct objfile *objfile = NULL; struct objfile *last_one = NULL; mapped |= mapped_symbol_files; #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) { /* If we can support mapped symbol files, try to open/reopen the mapped file that corresponds to the file from which we wish to read symbols. If the objfile is to be mapped, we must malloc the structure itself using the mmap version, and arrange that all memory allocation for the objfile uses the mmap routines. If we are reusing an existing mapped file, from which we get our objfile pointer, we have to make sure that we update the pointers to the alloc/free functions in the obstack, in case these functions have moved within the current gdb. */ int fd; #ifdef NeXT fd = open_mapped_file ([(SegmentManager *)manager executableName], [(SegmentManager *)manager mtime], mapped); #else fd = open_mapped_file (bfd_get_filename (abfd), bfd_get_mtime (abfd), mapped); #endif /* NeXT */ if (fd >= 0) { CORE_ADDR mapto; PTR md; if (((mapto = map_to_address ()) == 0) || ((md = mmalloc_attach (fd, (PTR) mapto)) == NULL)) { close (fd); } else if ((objfile = (struct objfile *) mmalloc_getkey (md, 0)) != NULL) { /* Update memory corruption handler function addresses. */ init_malloc (md); objfile -> md = md; objfile -> mmfd = fd; /* Update pointers to functions to *our* copies */ obstack_chunkfun (&objfile -> psymbol_obstack, xmmalloc); obstack_freefun (&objfile -> psymbol_obstack, mfree); obstack_chunkfun (&objfile -> symbol_obstack, xmmalloc); obstack_freefun (&objfile -> symbol_obstack, mfree); obstack_chunkfun (&objfile -> type_obstack, xmmalloc); obstack_freefun (&objfile -> type_obstack, mfree); /* If already in objfile list, unlink it. */ unlink_objfile (objfile); /* Forget things specific to a particular gdb, may have changed. */ objfile -> sf = NULL; } else { /* Set up to detect internal memory corruption. MUST be done before the first malloc. See comments in init_malloc() and mmcheck(). */ init_malloc (md); objfile = (struct objfile *) xmmalloc (md, sizeof (struct objfile)); memset (objfile, 0, sizeof (struct objfile)); objfile -> md = md; objfile -> mmfd = fd; objfile -> flags |= OBJF_MAPPED; mmalloc_setkey (objfile -> md, 0, objfile); obstack_specify_allocation_with_arg (&objfile -> psymbol_obstack, 0, 0, xmmalloc, mfree, objfile -> md); obstack_specify_allocation_with_arg (&objfile -> symbol_obstack, 0, 0, xmmalloc, mfree, objfile -> md); obstack_specify_allocation_with_arg (&objfile -> type_obstack, 0, 0, xmmalloc, mfree, objfile -> md); } } if (mapped && (objfile == NULL)) { #ifdef NeXT warning ("symbol table for '%s' will not be mapped", [(SegmentManager *)manager executableName]); #else warning ("symbol table for '%s' will not be mapped", bfd_get_filename (abfd)); #endif /* NeXT */ } } #else /* defined(NO_MMALLOC) || !defined(HAVE_MMAP) */ if (mapped) { warning ("this version of gdb does not support mapped symbol tables."); /* Turn off the global flag so we don't try to do mapped symbol tables any more, which shuts up gdb unless the user specifically gives the "mapped" keyword again. */ mapped_symbol_files = 0; } #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ /* If we don't support mapped symbol files, didn't ask for the file to be mapped, or failed to open the mapped file for some reason, then revert back to an unmapped objfile. */ if (objfile == NULL) { #ifdef NeXT NXZone *zone = NXCreateZone(vm_page_size, vm_page_size, 1); objfile = (struct objfile *)NXZoneMalloc(zone, sizeof (struct objfile)); memset (objfile, 0, sizeof (struct objfile)); objfile -> md = zone; obstack_specify_allocation_with_arg (&objfile -> psymbol_obstack, 0, 0, zone->malloc, zone->free, zone); obstack_specify_allocation_with_arg (&objfile -> symbol_obstack, 0, 0, zone->malloc, zone->free, zone); obstack_specify_allocation_with_arg (&objfile -> type_obstack, 0, 0, zone->malloc, zone->free, zone); #else objfile = (struct objfile *) xmalloc (sizeof (struct objfile)); memset (objfile, 0, sizeof (struct objfile)); objfile -> md = NULL; obstack_specify_allocation (&objfile -> psymbol_obstack, 0, 0, xmalloc, free); obstack_specify_allocation (&objfile -> symbol_obstack, 0, 0, xmalloc, free); obstack_specify_allocation (&objfile -> type_obstack, 0, 0, xmalloc, free); #endif /* NeXT */ } /* Update the per-objfile information that comes from the bfd, ensuring that any data that is reference is saved in the per-objfile data region. */ #ifdef NeXT objfile->manager = manager; objfile->start = (CORE_ADDR)[(SegmentManager *)manager originalPointerFor: [(SegmentManager *)manager getMachHeader]] ; objfile->end = (CORE_ADDR)[(SegmentManager *)manager getMaximumTextAddress]; #else objfile -> obfd = abfd; #endif /* NeXT */ if (objfile -> name != NULL) { mfree (objfile -> md, objfile -> name); } #ifdef NeXT objfile -> name = mstrsave (objfile -> md, [(SegmentManager *)manager executableName]); objfile -> mtime = [(SegmentManager *)manager mtime]; #else objfile -> name = mstrsave (objfile -> md, bfd_get_filename (abfd)); objfile -> mtime = bfd_get_mtime (abfd); /* Build section table. */ if (build_objfile_section_table (objfile)) { error ("Can't find the file sections in `%s': %s", objfile -> name, bfd_errmsg (bfd_get_error ())); } #endif /* NeXT */ /* Add this file onto the tail of the linked list of other such files. */ objfile -> next = NULL; if (object_files == NULL) object_files = objfile; else { for (last_one = object_files; last_one -> next; last_one = last_one -> next); last_one -> next = objfile; } return (objfile); } /* Put OBJFILE at the front of the list. */ void objfile_to_front (objfile) struct objfile *objfile; { struct objfile **objp; for (objp = &object_files; *objp != NULL; objp = &((*objp)->next)) { if (*objp == objfile) { /* Unhook it from where it is. */ *objp = objfile->next; /* Put it in the front. */ objfile->next = object_files; object_files = objfile; break; } } } /* Unlink OBJFILE from the list of known objfiles, if it is found in the list. It is not a bug, or error, to call this function if OBJFILE is not known to be in the current list. This is done in the case of mapped objfiles, for example, just to ensure that the mapped objfile doesn't appear twice in the list. Since the list is threaded, linking in a mapped objfile twice would create a circular list. If OBJFILE turns out to be in the list, we zap it's NEXT pointer after unlinking it, just to ensure that we have completely severed any linkages between the OBJFILE and the list. */ void unlink_objfile (objfile) struct objfile *objfile; { struct objfile** objpp; for (objpp = &object_files; *objpp != NULL; objpp = &((*objpp) -> next)) { if (*objpp == objfile) { *objpp = (*objpp) -> next; objfile -> next = NULL; break; } } } /* Destroy an objfile and all the symtabs and psymtabs under it. Note that as much as possible is allocated on the symbol_obstack and psymbol_obstack, so that the memory can be efficiently freed. Things which we do NOT free because they are not in malloc'd memory or not in memory specific to the objfile include: objfile -> sf FIXME: If the objfile is using reusable symbol information (via mmalloc), then we need to take into account the fact that more than one process may be using the symbol information at the same time (when mmalloc is extended to support cooperative locking). When more than one process is using the mapped symbol info, we need to be more careful about when we free objects in the reusable area. */ void free_objfile (objfile) struct objfile *objfile; { /* First do any symbol file specific actions required when we are finished with a particular symbol file. Note that if the objfile is using reusable symbol information (via mmalloc) then each of these routines is responsible for doing the correct thing, either freeing things which are valid only during this particular gdb execution, or leaving them to be reused during the next one. */ if (objfile -> sf != NULL) { (*objfile -> sf -> sym_finish) (objfile); } /* We always close the bfd. */ #ifndef NeXT if (objfile -> obfd != NULL) { char *name = bfd_get_filename (objfile->obfd); if (!bfd_close (objfile -> obfd)) warning ("cannot close \"%s\": %s", name, bfd_errmsg (bfd_get_error ())); free (name); } #endif /* NeXT */ /* Remove it from the chain of all objfiles. */ unlink_objfile (objfile); /* If we are going to free the runtime common objfile, mark it as unallocated. */ if (objfile == rt_common_objfile) rt_common_objfile = NULL; /* Before the symbol table code was redone to make it easier to selectively load and remove information particular to a specific linkage unit, gdb used to do these things whenever the monolithic symbol table was blown away. How much still needs to be done is unknown, but we play it safe for now and keep each action until it is shown to be no longer needed. */ #if defined (CLEAR_SOLIB) CLEAR_SOLIB (); /* CLEAR_SOLIB closes the bfd's for any shared libraries. But the to_sections for a core file might refer to those bfd's. So detach any core file. */ { struct target_ops *t = find_core_target (); if (t != NULL) (t->to_detach) (NULL, 0); } #endif /* I *think* all our callers call clear_symtab_users. If so, no need to call this here. */ clear_pc_function_cache (); #ifdef NeXT /* This hash contains references to symbols that may be in this objfile */ clear_stabsread_hash (); #endif /* NeXT */ /* The last thing we do is free the objfile struct itself for the non-reusable case, or detach from the mapped file for the reusable case. Note that the mmalloc_detach or the mfree is the last thing we can do with this objfile. */ #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) if (objfile -> flags & OBJF_MAPPED) { /* Remember the fd so we can close it. We can't close it before doing the detach, and after the detach the objfile is gone. */ int mmfd; mmfd = objfile -> mmfd; mmalloc_detach (objfile -> md); objfile = NULL; close (mmfd); } #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ /* If we still have an objfile, then either we don't support reusable objfiles or this one was not reusable. So free it normally. */ if (objfile != NULL) { #ifdef NeXT NXDestroyZone((NXZone *)objfile->md); #else if (objfile -> name != NULL) { mfree (objfile -> md, objfile -> name); } if (objfile->global_psymbols.list) mfree (objfile->md, objfile->global_psymbols.list); if (objfile->static_psymbols.list) mfree (objfile->md, objfile->static_psymbols.list); /* Free the obstacks for non-reusable objfiles */ obstack_free (&objfile -> psymbol_obstack, 0); obstack_free (&objfile -> symbol_obstack, 0); obstack_free (&objfile -> type_obstack, 0); mfree (objfile -> md, objfile); #endif /* NeXT */ objfile = NULL; } } /* Free all the object files at once and clean up their users. */ void free_all_objfiles () { struct objfile *objfile, *temp; ALL_OBJFILES_SAFE (objfile, temp) { free_objfile (objfile); } clear_symtab_users (); } /* Relocate OBJFILE to NEW_OFFSETS. There should be OBJFILE->NUM_SECTIONS entries in new_offsets. */ void objfile_relocate (objfile, new_offsets) struct objfile *objfile; struct section_offsets *new_offsets; { struct section_offsets *delta = (struct section_offsets *) alloca (sizeof (struct section_offsets) + objfile->num_sections * sizeof (delta->offsets)); { int i; int something_changed = 0; for (i = 0; i < objfile->num_sections; ++i) { ANOFFSET (delta, i) = ANOFFSET (new_offsets, i) - ANOFFSET (objfile->section_offsets, i); if (ANOFFSET (delta, i) != 0) something_changed = 1; } if (!something_changed) return; } /* OK, get all the symtabs. */ { struct symtab *s; ALL_OBJFILE_SYMTABS (objfile, s) { struct linetable *l; struct blockvector *bv; int i; /* First the line table. */ l = LINETABLE (s); if (l) { for (i = 0; i < l->nitems; ++i) l->item[i].pc += ANOFFSET (delta, s->block_line_section); } /* Don't relocate a shared blockvector more than once. */ if (!s->primary) continue; bv = BLOCKVECTOR (s); for (i = 0; i < BLOCKVECTOR_NBLOCKS (bv); ++i) { struct block *b; int j; b = BLOCKVECTOR_BLOCK (bv, i); BLOCK_START (b) += ANOFFSET (delta, s->block_line_section); BLOCK_END (b) += ANOFFSET (delta, s->block_line_section); for (j = 0; j < BLOCK_NSYMS (b); ++j) { struct symbol *sym = BLOCK_SYM (b, j); /* The RS6000 code from which this was taken skipped any symbols in STRUCT_NAMESPACE or UNDEF_NAMESPACE. But I'm leaving out that test, on the theory that they can't possibly pass the tests below. */ if ((SYMBOL_CLASS (sym) == LOC_LABEL || SYMBOL_CLASS (sym) == LOC_STATIC) && SYMBOL_SECTION (sym) >= 0) { SYMBOL_VALUE_ADDRESS (sym) += ANOFFSET (delta, SYMBOL_SECTION (sym)); } #ifdef MIPS_EFI_SYMBOL_NAME /* Relocate Extra Function Info for ecoff. */ else if (SYMBOL_CLASS (sym) == LOC_CONST && SYMBOL_NAMESPACE (sym) == LABEL_NAMESPACE && STRCMP (SYMBOL_NAME (sym), MIPS_EFI_SYMBOL_NAME) == 0) ecoff_relocate_efi (sym, ANOFFSET (delta, s->block_line_section)); #endif } } } } { struct partial_symtab *p; ALL_OBJFILE_PSYMTABS (objfile, p) { /* FIXME: specific to symbol readers which use gdb-stabs.h. We can only get away with it since objfile_relocate is only used on XCOFF, which lacks psymtabs, and for gdb-stabs.h targets. */ p->textlow += ANOFFSET (delta, SECT_OFF_TEXT); p->texthigh += ANOFFSET (delta, SECT_OFF_TEXT); } } { struct partial_symbol *psym; for (psym = objfile->global_psymbols.list; psym < objfile->global_psymbols.next; psym++) if (SYMBOL_SECTION (psym) >= 0) SYMBOL_VALUE_ADDRESS (psym) += ANOFFSET (delta, SYMBOL_SECTION (psym)); for (psym = objfile->static_psymbols.list; psym < objfile->static_psymbols.next; psym++) if (SYMBOL_SECTION (psym) >= 0) SYMBOL_VALUE_ADDRESS (psym) += ANOFFSET (delta, SYMBOL_SECTION (psym)); } { struct minimal_symbol *msym; ALL_OBJFILE_MSYMBOLS (objfile, msym) if (SYMBOL_SECTION (msym) >= 0) SYMBOL_VALUE_ADDRESS (msym) += ANOFFSET (delta, SYMBOL_SECTION (msym)); } /* Relocating different sections by different amounts may cause the symbols to be out of order. */ msymbols_sort (objfile); { int i; for (i = 0; i < objfile->num_sections; ++i) ANOFFSET (objfile->section_offsets, i) = ANOFFSET (new_offsets, i); } #ifndef DONT_USE_BFD { struct obj_section *s; bfd *abfd; abfd = objfile->obfd; for (s = objfile->sections; s < objfile->sections_end; ++s) { flagword flags; flags = bfd_get_section_flags (abfd, s->the_bfd_section); if (flags & SEC_CODE) { s->addr += ANOFFSET (delta, SECT_OFF_TEXT); s->endaddr += ANOFFSET (delta, SECT_OFF_TEXT); } else if (flags & (SEC_DATA | SEC_LOAD)) { s->addr += ANOFFSET (delta, SECT_OFF_DATA); s->endaddr += ANOFFSET (delta, SECT_OFF_DATA); } else if (flags & SEC_ALLOC) { s->addr += ANOFFSET (delta, SECT_OFF_BSS); s->endaddr += ANOFFSET (delta, SECT_OFF_BSS); } } } #endif /* DONT_USE_BFD */ if (objfile->ei.entry_point != ~0) objfile->ei.entry_point += ANOFFSET (delta, SECT_OFF_TEXT); if (objfile->ei.entry_func_lowpc != INVALID_ENTRY_LOWPC) { objfile->ei.entry_func_lowpc += ANOFFSET (delta, SECT_OFF_TEXT); objfile->ei.entry_func_highpc += ANOFFSET (delta, SECT_OFF_TEXT); } if (objfile->ei.entry_file_lowpc != INVALID_ENTRY_LOWPC) { objfile->ei.entry_file_lowpc += ANOFFSET (delta, SECT_OFF_TEXT); objfile->ei.entry_file_highpc += ANOFFSET (delta, SECT_OFF_TEXT); } if (objfile->ei.main_func_lowpc != INVALID_ENTRY_LOWPC) { objfile->ei.main_func_lowpc += ANOFFSET (delta, SECT_OFF_TEXT); objfile->ei.main_func_highpc += ANOFFSET (delta, SECT_OFF_TEXT); } } /* Many places in gdb want to test just to see if we have any partial symbols available. This function returns zero if none are currently available, nonzero otherwise. */ int have_partial_symbols () { struct objfile *ofp; ALL_OBJFILES (ofp) { if (ofp -> psymtabs != NULL) { return 1; } } return 0; } /* Many places in gdb want to test just to see if we have any full symbols available. This function returns zero if none are currently available, nonzero otherwise. */ int have_full_symbols () { struct objfile *ofp; ALL_OBJFILES (ofp) { if (ofp -> symtabs != NULL) { return 1; } } return 0; } /* Many places in gdb want to test just to see if we have any minimal symbols available. This function returns zero if none are currently available, nonzero otherwise. */ int have_minimal_symbols () { struct objfile *ofp; ALL_OBJFILES (ofp) { if (ofp -> msymbols != NULL) { return 1; } } return 0; } #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) /* Given the name of a mapped symbol file in SYMSFILENAME, and the timestamp of the corresponding symbol file in MTIME, try to open an existing file with the name SYMSFILENAME and verify it is more recent than the base file by checking it's timestamp against MTIME. If SYMSFILENAME does not exist (or can't be stat'd), simply returns -1. If SYMSFILENAME does exist, but is out of date, we check to see if the user has specified creation of a mapped file. If so, we don't issue any warning message because we will be creating a new mapped file anyway, overwriting the old one. If not, then we issue a warning message so that the user will know why we aren't using this existing mapped symbol file. In either case, we return -1. If SYMSFILENAME does exist and is not out of date, but can't be opened for some reason, then prints an appropriate system error message and returns -1. Otherwise, returns the open file descriptor. */ static int open_existing_mapped_file (symsfilename, mtime, mapped) char *symsfilename; long mtime; int mapped; { int fd = -1; struct stat sbuf; if (stat (symsfilename, &sbuf) == 0) { if (sbuf.st_mtime < mtime) { if (!mapped) { warning ("mapped symbol file `%s' is out of date, ignored it", symsfilename); } } else if ((fd = open (symsfilename, O_RDWR)) < 0) { if (error_pre_print) { printf_unfiltered (error_pre_print); } print_sys_errmsg (symsfilename, errno); } } return (fd); } /* Look for a mapped symbol file that corresponds to FILENAME and is more recent than MTIME. If MAPPED is nonzero, the user has asked that gdb use a mapped symbol file for this file, so create a new one if one does not currently exist. If found, then return an open file descriptor for the file, otherwise return -1. This routine is responsible for implementing the policy that generates the name of the mapped symbol file from the name of a file containing symbols that gdb would like to read. Currently this policy is to append ".syms" to the name of the file. This routine is also responsible for implementing the policy that determines where the mapped symbol file is found (the search path). This policy is that when reading an existing mapped file, a file of the correct name in the current directory takes precedence over a file of the correct name in the same directory as the symbol file. When creating a new mapped file, it is always created in the current directory. This helps to minimize the chances of a user unknowingly creating big mapped files in places like /bin and /usr/local/bin, and allows a local copy to override a manually installed global copy (in /bin for example). */ static int open_mapped_file (filename, mtime, mapped) char *filename; long mtime; int mapped; { int fd; char *symsfilename; /* First try to open an existing file in the current directory, and then try the directory where the symbol file is located. */ symsfilename = concat ("./", basename (filename), ".syms", (char *) NULL); if ((fd = open_existing_mapped_file (symsfilename, mtime, mapped)) < 0) { free (symsfilename); symsfilename = concat (filename, ".syms", (char *) NULL); fd = open_existing_mapped_file (symsfilename, mtime, mapped); } /* If we don't have an open file by now, then either the file does not already exist, or the base file has changed since it was created. In either case, if the user has specified use of a mapped file, then create a new mapped file, truncating any existing one. If we can't create one, print a system error message saying why we can't. By default the file is rw for everyone, with the user's umask taking care of turning off the permissions the user wants off. */ if ((fd < 0) && mapped) { free (symsfilename); symsfilename = concat ("./", basename (filename), ".syms", (char *) NULL); if ((fd = open (symsfilename, O_RDWR | O_CREAT | O_TRUNC, 0666)) < 0) { if (error_pre_print) { printf_unfiltered (error_pre_print); } print_sys_errmsg (symsfilename, errno); } } free (symsfilename); return (fd); } /* Return the base address at which we would like the next objfile's mapped data to start. For now, we use the kludge that the configuration specifies a base address to which it is safe to map the first mmalloc heap, and an increment to add to this address for each successive heap. There are a lot of issues to deal with here to make this work reasonably, including: Avoid memory collisions with existing mapped address spaces Reclaim address spaces when their mmalloc heaps are unmapped When mmalloc heaps are shared between processes they have to be mapped at the same addresses in each Once created, a mmalloc heap that is to be mapped back in must be mapped at the original address. I.E. each objfile will expect to be remapped at it's original address. This becomes a problem if the desired address is already in use. etc, etc, etc. */ static CORE_ADDR map_to_address () { #if defined(MMAP_BASE_ADDRESS) && defined (MMAP_INCREMENT) static CORE_ADDR next = MMAP_BASE_ADDRESS; CORE_ADDR mapto = next; next += MMAP_INCREMENT; return (mapto); #else return (0); #endif } #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ #ifndef DONT_USE_BFD /* Returns a section whose range includes PC or NULL if none found. */ struct obj_section * find_pc_section(pc) CORE_ADDR pc; { struct obj_section *s; struct objfile *objfile; ALL_OBJFILES (objfile) for (s = objfile->sections; s < objfile->sections_end; ++s) if (s->addr <= pc && pc < s->endaddr) return(s); return(NULL); } /* In SVR4, we recognize a trampoline by it's section name. That is, if the pc is in a section named ".plt" then we are in a trampoline. */ int in_plt_section(pc, name) CORE_ADDR pc; char *name; { struct obj_section *s; int retval = 0; s = find_pc_section(pc); retval = (s != NULL && s->the_bfd_section->name != NULL && STREQ (s->the_bfd_section->name, ".plt")); return(retval); } #endif /* DONT_USE_BFD */
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.