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Diffstat (limited to 'gdb/objfiles.c')
-rw-r--r-- | gdb/objfiles.c | 1011 |
1 files changed, 1011 insertions, 0 deletions
diff --git a/gdb/objfiles.c b/gdb/objfiles.c new file mode 100644 index 0000000..9c5e49f --- /dev/null +++ b/gdb/objfiles.c @@ -0,0 +1,1011 @@ +/* GDB routines for manipulating objfiles. + + Copyright 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, + 2001, 2002 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 "bcache.h" + +#include <sys/types.h> +#include "gdb_stat.h" +#include <fcntl.h> +#include "gdb_obstack.h" +#include "gdb_string.h" + +#include "breakpoint.h" + +/* Prototypes for local functions */ + +#if defined(USE_MMALLOC) && defined(HAVE_MMAP) + +#include "mmalloc.h" + +static int open_existing_mapped_file (char *, long, int); + +static int open_mapped_file (char *filename, long mtime, int flags); + +static PTR map_to_file (int); + +#endif /* defined(USE_MMALLOC) && defined(HAVE_MMAP) */ + +static void add_to_objfile_sections (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 + +/* Called via bfd_map_over_sections to build up the section table that + the objfile references. The objfile contains pointers to the start + of the table (objfile->sections) and to the first location after + the end of the table (objfile->sections_end). */ + +static void +add_to_objfile_sections (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). + + Note that while we are building the table, which goes into the + psymbol obstack, we hijack the sections_end pointer to instead hold + a count of the number of sections. When bfd_map_over_sections + returns, this count is used to compute the pointer to the end of + the sections table, which then overwrites the count. + + Also note that the OFFSET and OVLY_MAPPED in each table entry + are initialized to zero. + + Also note that if anything else writes to the psymbol obstack while + we are building the table, we're pretty much hosed. */ + +int +build_objfile_section_table (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 some flag bits + 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. + + The FLAGS word contains various bits (OBJF_*) that can be taken as + requests for specific operations, like trying to open a mapped + version of the objfile (OBJF_MAPPED). Other bits like + OBJF_SHARED are simply copied through to the new objfile flags + member. */ + +struct objfile * +allocate_objfile (bfd *abfd, int flags) +{ + struct objfile *objfile = NULL; + struct objfile *last_one = NULL; + + if (mapped_symbol_files) + flags |= OBJF_MAPPED; + +#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), + flags); + 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, xmfree); + obstack_chunkfun (&objfile->macro_cache.cache, xmmalloc); + obstack_freefun (&objfile->macro_cache.cache, xmfree); + obstack_chunkfun (&objfile->psymbol_obstack, xmmalloc); + obstack_freefun (&objfile->psymbol_obstack, xmfree); + obstack_chunkfun (&objfile->symbol_obstack, xmmalloc); + obstack_freefun (&objfile->symbol_obstack, xmfree); + obstack_chunkfun (&objfile->type_obstack, xmmalloc); + obstack_freefun (&objfile->type_obstack, xmfree); + /* 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, xmfree, + objfile->md); + obstack_specify_allocation_with_arg (&objfile->macro_cache.cache, + 0, 0, xmmalloc, xmfree, + objfile->md); + obstack_specify_allocation_with_arg (&objfile->psymbol_obstack, + 0, 0, xmmalloc, xmfree, + objfile->md); + obstack_specify_allocation_with_arg (&objfile->symbol_obstack, + 0, 0, xmmalloc, xmfree, + objfile->md); + obstack_specify_allocation_with_arg (&objfile->type_obstack, + 0, 0, xmmalloc, xmfree, + objfile->md); + } + } + + if ((flags & OBJF_MAPPED) && (objfile == NULL)) + { + warning ("symbol table for '%s' will not be mapped", + bfd_get_filename (abfd)); + flags &= ~OBJF_MAPPED; + } + } +#else /* !defined(USE_MMALLOC) || !defined(HAVE_MMAP) */ + + if (flags & OBJF_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; + flags &= ~OBJF_MAPPED; + } + +#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; + objfile->psymbol_cache = bcache_xmalloc (); + objfile->macro_cache = bcache_xmalloc (); + obstack_specify_allocation (&objfile->psymbol_obstack, 0, 0, xmalloc, + xfree); + obstack_specify_allocation (&objfile->symbol_obstack, 0, 0, xmalloc, + xfree); + obstack_specify_allocation (&objfile->type_obstack, 0, 0, xmalloc, + xfree); + flags &= ~OBJF_MAPPED; + } + + /* 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) + { + xmfree (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 ())); + } + } + + /* Initialize the section indexes for this objfile, so that we can + later detect if they are used w/o being properly assigned to. */ + + objfile->sect_index_text = -1; + objfile->sect_index_data = -1; + objfile->sect_index_bss = -1; + objfile->sect_index_rodata = -1; + + /* 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; + } + + /* Save passed in flag bits. */ + objfile->flags |= flags; + + return (objfile); +} + +/* Put OBJFILE at the front of the list. */ + +void +objfile_to_front (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 (struct objfile *objfile) +{ + struct objfile **objpp; + + for (objpp = &object_files; *objpp != NULL; objpp = &((*objpp)->next)) + { + if (*objpp == objfile) + { + *objpp = (*objpp)->next; + objfile->next = NULL; + return; + } + } + + internal_error (__FILE__, __LINE__, + "unlink_objfile: objfile already unlinked"); +} + + +/* 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 (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 ())); + xfree (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. */ + + /* 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 xmfree() 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) + { + xmfree (objfile->md, objfile->name); + } + if (objfile->global_psymbols.list) + xmfree (objfile->md, objfile->global_psymbols.list); + if (objfile->static_psymbols.list) + xmfree (objfile->md, objfile->static_psymbols.list); + /* Free the obstacks for non-reusable objfiles */ + bcache_xfree (objfile->psymbol_cache); + bcache_xfree (objfile->macro_cache); + obstack_free (&objfile->psymbol_obstack, 0); + obstack_free (&objfile->symbol_obstack, 0); + obstack_free (&objfile->type_obstack, 0); + xmfree (objfile->md, objfile); + objfile = NULL; + } +} + +static void +do_free_objfile_cleanup (void *obj) +{ + free_objfile (obj); +} + +struct cleanup * +make_cleanup_free_objfile (struct objfile *obj) +{ + return make_cleanup (do_free_objfile_cleanup, obj); +} + +/* Free all the object files at once and clean up their users. */ + +void +free_all_objfiles (void) +{ + 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 (struct objfile *objfile, struct section_offsets *new_offsets) +{ + struct section_offsets *delta = + (struct section_offsets *) alloca (SIZEOF_SECTION_OFFSETS); + + { + int i; + int something_changed = 0; + for (i = 0; i < objfile->num_sections; ++i) + { + delta->offsets[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; + struct symbol *sym; + 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); + + ALL_BLOCK_SYMBOLS (b, j, sym) + { + fixup_symbol_section (sym, objfile); + + /* 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 (objfile)); + p->texthigh += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + } + } + + { + struct partial_symbol **psym; + + for (psym = objfile->global_psymbols.list; + psym < objfile->global_psymbols.next; + psym++) + { + fixup_psymbol_section (*psym, objfile); + 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++) + { + fixup_psymbol_section (*psym, objfile); + 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) + (objfile->section_offsets)->offsets[i] = ANOFFSET (new_offsets, i); + } + + if (objfile->ei.entry_point != ~(CORE_ADDR) 0) + { + /* Relocate ei.entry_point with its section offset, use SECT_OFF_TEXT + only as a fallback. */ + struct obj_section *s; + s = find_pc_section (objfile->ei.entry_point); + if (s) + objfile->ei.entry_point += ANOFFSET (delta, s->the_bfd_section->index); + else + objfile->ei.entry_point += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + } + + { + struct obj_section *s; + bfd *abfd; + + abfd = objfile->obfd; + + ALL_OBJFILE_OSECTIONS (objfile, s) + { + int idx = s->the_bfd_section->index; + + s->addr += ANOFFSET (delta, idx); + s->endaddr += ANOFFSET (delta, idx); + } + } + + if (objfile->ei.entry_func_lowpc != INVALID_ENTRY_LOWPC) + { + objfile->ei.entry_func_lowpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + objfile->ei.entry_func_highpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + } + + if (objfile->ei.entry_file_lowpc != INVALID_ENTRY_LOWPC) + { + objfile->ei.entry_file_lowpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + objfile->ei.entry_file_highpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + } + + if (objfile->ei.main_func_lowpc != INVALID_ENTRY_LOWPC) + { + objfile->ei.main_func_lowpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + objfile->ei.main_func_highpc += ANOFFSET (delta, SECT_OFF_TEXT (objfile)); + } + + /* 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 (void) +{ + 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 (void) +{ + 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 (void) +{ + 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->flags & OBJF_USERLOADED) && (objf->flags & OBJF_SHARED)) + 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 (void) +{ + 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 (char *symsfilename, long mtime, int flags) +{ + int fd = -1; + struct stat sbuf; + + if (stat (symsfilename, &sbuf) == 0) + { + if (sbuf.st_mtime < mtime) + { + if (!(flags & OBJF_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 (char *filename, long mtime, int flags) +{ + 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 ("./", lbasename (filename), ".syms", (char *) NULL); + if ((fd = open_existing_mapped_file (symsfilename, mtime, flags)) < 0) + { + xfree (symsfilename); + symsfilename = concat (filename, ".syms", (char *) NULL); + fd = open_existing_mapped_file (symsfilename, mtime, flags); + } + + /* 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) && (flags & OBJF_MAPPED)) + { + xfree (symsfilename); + symsfilename = concat ("./", lbasename (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); + } + } + + xfree (symsfilename); + return (fd); +} + +static PTR +map_to_file (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 (CORE_ADDR pc, struct sec *section) +{ + struct obj_section *s; + struct objfile *objfile; + + ALL_OBJSECTIONS (objfile, s) + if ((section == 0 || section == s->the_bfd_section) && + s->addr <= pc && pc < s->endaddr) + 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 (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 (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); +} + +/* Return nonzero if NAME is in the import list of OBJFILE. Else + return zero. */ + +int +is_in_import_list (char *name, struct objfile *objfile) +{ + register int i; + + if (!objfile || !name || !*name) + return 0; + + for (i = 0; i < objfile->import_list_size; i++) + if (objfile->import_list[i] && STREQ (name, objfile->import_list[i])) + return 1; + return 0; +} + |