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author | Stan Shebs <shebs@codesourcery.com> | 1999-04-16 01:35:26 +0000 |
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committer | Stan Shebs <shebs@codesourcery.com> | 1999-04-16 01:35:26 +0000 |
commit | c906108c21474dfb4ed285bcc0ac6fe02cd400cc (patch) | |
tree | a0015aa5cedc19ccbab307251353a41722a3ae13 /gdb/objfiles.c | |
parent | cd946cff9ede3f30935803403f06f6ed30cad136 (diff) | |
download | gdb-c906108c21474dfb4ed285bcc0ac6fe02cd400cc.zip gdb-c906108c21474dfb4ed285bcc0ac6fe02cd400cc.tar.gz gdb-c906108c21474dfb4ed285bcc0ac6fe02cd400cc.tar.bz2 |
Initial creation of sourceware repositorygdb-4_18-branchpoint
Diffstat (limited to 'gdb/objfiles.c')
-rw-r--r-- | gdb/objfiles.c | 988 |
1 files changed, 988 insertions, 0 deletions
diff --git a/gdb/objfiles.c b/gdb/objfiles.c new file mode 100644 index 0000000..971a7d4 --- /dev/null +++ b/gdb/objfiles.c @@ -0,0 +1,988 @@ +/* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* This file contains support routines for creating, manipulating, and + destroying objfile structures. */ + +#include "defs.h" +#include "bfd.h" /* Binary File Description */ +#include "symtab.h" +#include "symfile.h" +#include "objfiles.h" +#include "gdb-stabs.h" +#include "target.h" + +#include <sys/types.h> +#include "gdb_stat.h" +#include <fcntl.h> +#include "obstack.h" +#include "gdb_string.h" + +/* Prototypes for local functions */ + +#if defined(USE_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 PTR +map_to_file PARAMS ((int)); + +#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */ + +static void +add_to_objfile_sections PARAMS ((bfd *, sec_ptr, PTR)); + +/* 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 */ + +/* 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. */ + +#ifndef TARGET_KEEP_SECTION +#define TARGET_KEEP_SECTION(ASECT) 0 +#endif + +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) && !(TARGET_KEEP_SECTION(asect))) + return; + + if (0 == bfd_section_size (abfd, asect)) + return; + section.offset = 0; + section.objfile = objfile; + section.the_bfd_section = asect; + section.ovly_mapped = 0; + section.addr = bfd_section_vma (abfd, asect); + section.endaddr = section.addr + bfd_section_size (abfd, asect); + obstack_grow (&objfile->psymbol_obstack, (char *) §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); +} + +/* 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. + + USER_LOADED is simply recorded in the objfile. This record offers a way for + run_command to remove old objfile entries which are no longer valid (i.e., + are associated with an old inferior), but to preserve ones that the user + explicitly loaded via the add-symbol-file command. + + IS_SOLIB is also simply recorded in the objfile. */ + +struct objfile * +allocate_objfile (abfd, mapped, user_loaded, is_solib) + bfd *abfd; + int mapped; + int user_loaded; + int is_solib; +{ + struct objfile *objfile = NULL; + struct objfile *last_one = NULL; + + mapped |= mapped_symbol_files; + +#if defined(USE_MMALLOC) && defined(HAVE_MMAP) + if (abfd != NULL) + { + + /* 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; + + fd = open_mapped_file (bfd_get_filename (abfd), bfd_get_mtime (abfd), + mapped); + if (fd >= 0) + { + PTR md; + + if ((md = map_to_file (fd)) == 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_cache.cache, xmmalloc); + obstack_freefun (&objfile -> psymbol_cache.cache, mfree); + 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_cache.cache, + 0, 0, xmmalloc, mfree, + objfile -> md); + 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)) + { + warning ("symbol table for '%s' will not be mapped", + bfd_get_filename (abfd)); + } + } +#else /* !defined(USE_MMALLOC) || !defined(HAVE_MMAP) */ + + if (mapped) + { + warning ("mapped symbol tables are not supported on this machine; missing or broken mmap()."); + + /* 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(USE_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) + { + objfile = (struct objfile *) xmalloc (sizeof (struct objfile)); + memset (objfile, 0, sizeof (struct objfile)); + objfile -> md = NULL; + obstack_specify_allocation (&objfile -> psymbol_cache.cache, 0, 0, + xmalloc, free); + 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); + } + + /* 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. */ + + objfile -> obfd = abfd; + if (objfile -> name != NULL) + { + mfree (objfile -> md, objfile -> name); + } + if (abfd != NULL) + { + 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 ())); + } + } + + /* 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; + } + + /* Record whether this objfile was created because the user explicitly + caused it (e.g., used the add-symbol-file command). + */ + objfile -> user_loaded = user_loaded; + + /* Record whether this objfile definitely represents a solib. */ + objfile -> is_solib = is_solib; + + 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. */ + + 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); + } + + /* 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 (); + + /* 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(USE_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(USE_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) + { + 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_cache.cache, 0); + obstack_free (&objfile -> psymbol_obstack, 0); + obstack_free (&objfile -> symbol_obstack, 0); + obstack_free (&objfile -> type_obstack, 0); + mfree (objfile -> md, objfile); + 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_CLASS (sym) == LOC_INDIRECT) + && 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) + { + 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); + } + + { + 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); + } + } + } + + if (objfile->ei.entry_point != ~(CORE_ADDR)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); + } + + /* Relocate breakpoints as necessary, after things are relocated. */ + breakpoint_re_set (); +} + +/* 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; +} + + +/* This operations deletes all objfile entries that represent solibs that + weren't explicitly loaded by the user, via e.g., the add-symbol-file + command. + */ +void +objfile_purge_solibs () +{ + struct objfile * objf; + struct objfile * temp; + + ALL_OBJFILES_SAFE (objf, temp) + { + /* We assume that the solib package has been purged already, or will + be soon. + */ + if (! objf->user_loaded && objf->is_solib) + free_objfile (objf); + } +} + + +/* 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(USE_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); +} + +static PTR +map_to_file (fd) + int fd; +{ + PTR md; + CORE_ADDR mapto; + + md = mmalloc_attach (fd, (PTR) 0); + if (md != NULL) + { + mapto = (CORE_ADDR) mmalloc_getkey (md, 1); + md = mmalloc_detach (md); + if (md != NULL) + { + /* FIXME: should figure out why detach failed */ + md = NULL; + } + else if (mapto != (CORE_ADDR) NULL) + { + /* This mapping file needs to be remapped at "mapto" */ + md = mmalloc_attach (fd, (PTR) mapto); + } + else + { + /* This is a freshly created mapping file. */ + mapto = (CORE_ADDR) mmalloc_findbase (20 * 1024 * 1024); + if (mapto != 0) + { + /* To avoid reusing the freshly created mapping file, at the + address selected by mmap, we must truncate it before trying + to do an attach at the address we want. */ + ftruncate (fd, 0); + md = mmalloc_attach (fd, (PTR) mapto); + if (md != NULL) + { + mmalloc_setkey (md, 1, (PTR) mapto); + } + } + } + } + return (md); +} + +#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */ + +/* Returns a section whose range includes PC and SECTION, + or NULL if none found. Note the distinction between the return type, + struct obj_section (which is defined in gdb), and the input type + struct sec (which is a bfd-defined data type). The obj_section + contains a pointer to the bfd struct sec section. */ + +struct obj_section * +find_pc_sect_section (pc, section) + CORE_ADDR pc; + struct sec *section; +{ + struct obj_section *s; + struct objfile *objfile; + + ALL_OBJFILES (objfile) + for (s = objfile->sections; s < objfile->sections_end; ++s) +#if defined(HPUXHPPA) + if ((section == 0 || section == s->the_bfd_section) && + s->addr <= pc && pc <= s->endaddr) +#else + if ((section == 0 || section == s->the_bfd_section) && + s->addr <= pc && pc < s->endaddr) +#endif + return(s); + + return(NULL); +} + +/* Returns a section whose range includes PC or NULL if none found. + Backward compatibility, no section. */ + +struct obj_section * +find_pc_section(pc) + CORE_ADDR pc; +{ + return find_pc_sect_section (pc, find_pc_mapped_section (pc)); +} + + +/* 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); +} |