diff options
Diffstat (limited to 'gdb/solib-svr4.c')
| -rw-r--r-- | gdb/solib-svr4.c | 88 |
1 files changed, 74 insertions, 14 deletions
diff --git a/gdb/solib-svr4.c b/gdb/solib-svr4.c index 8ef400d75a5..c71f26b7578 100644 --- a/gdb/solib-svr4.c +++ b/gdb/solib-svr4.c @@ -548,6 +548,17 @@ solib_svr4_r_map (void) builtin_type_void_data_ptr); } +/* Find r_brk from the inferior's debug base. */ + +static CORE_ADDR +solib_svr4_r_brk (void) +{ + struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); + + return read_memory_typed_address (debug_base + lmo->r_brk_offset, + builtin_type_void_data_ptr); +} + /* Find the link map for the dynamic linker (if it is not in the normal list of loaded shared objects). */ @@ -606,7 +617,9 @@ open_symbol_file_object (void *from_ttyp) if (!query ("Attempt to reload symbols from process? ")) return 0; - if ((debug_base = locate_base ()) == 0) + /* Always locate the debug struct, in case it has moved. */ + debug_base = 0; + if (locate_base () == 0) return 0; /* failed somehow... */ /* First link map member should be the executable. */ @@ -701,17 +714,14 @@ svr4_current_sos (void) struct so_list **link_ptr = &head; CORE_ADDR ldsomap = 0; - /* Make sure we've looked up the inferior's dynamic linker's base - structure. */ - if (! debug_base) - { - debug_base = locate_base (); + /* Always locate the debug struct, in case it has moved. */ + debug_base = 0; + locate_base (); - /* If we can't find the dynamic linker's base structure, this - must not be a dynamically linked executable. Hmm. */ - if (! debug_base) - return svr4_default_sos (); - } + /* If we can't find the dynamic linker's base structure, this + must not be a dynamically linked executable. Hmm. */ + if (! debug_base) + return svr4_default_sos (); /* Walk the inferior's link map list, and build our list of `struct so_list' nodes. */ @@ -800,7 +810,7 @@ svr4_fetch_objfile_link_map (struct objfile *objfile) { CORE_ADDR lm; - if ((debug_base = locate_base ()) == 0) + if (locate_base () == 0) return 0; /* failed somehow... */ /* Position ourselves on the first link map. */ @@ -965,6 +975,7 @@ enable_break (void) struct minimal_symbol *msymbol; char **bkpt_namep; asection *interp_sect; + CORE_ADDR sym_addr; /* First, remove all the solib event breakpoints. Their addresses may have changed since the last time we ran the program. */ @@ -973,6 +984,54 @@ enable_break (void) interp_text_sect_low = interp_text_sect_high = 0; interp_plt_sect_low = interp_plt_sect_high = 0; + /* If we already have a shared library list in the target, and + r_debug contains r_brk, set the breakpoint there - this should + mean r_brk has already been relocated. Assume the dynamic linker + is the object containing r_brk. */ + + solib_add (NULL, 0, ¤t_target, auto_solib_add); + sym_addr = 0; + if (debug_base && solib_svr4_r_map () != 0) + sym_addr = solib_svr4_r_brk (); + + if (sym_addr != 0) + { + struct obj_section *os; + + os = find_pc_section (sym_addr); + if (os != NULL) + { + /* Record the relocated start and end address of the dynamic linker + text and plt section for svr4_in_dynsym_resolve_code. */ + bfd *tmp_bfd; + CORE_ADDR load_addr; + + tmp_bfd = os->objfile->obfd; + load_addr = ANOFFSET (os->objfile->section_offsets, + os->objfile->sect_index_text); + + interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); + if (interp_sect) + { + interp_text_sect_low = + bfd_section_vma (tmp_bfd, interp_sect) + load_addr; + interp_text_sect_high = + interp_text_sect_low + bfd_section_size (tmp_bfd, interp_sect); + } + interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); + if (interp_sect) + { + interp_plt_sect_low = + bfd_section_vma (tmp_bfd, interp_sect) + load_addr; + interp_plt_sect_high = + interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect); + } + + create_solib_event_breakpoint (sym_addr); + return 1; + } + } + /* Find the .interp section; if not found, warn the user and drop into the old breakpoint at symbol code. */ interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); @@ -988,10 +1047,10 @@ enable_break (void) struct target_ops *tmp_bfd_target; int tmp_fd = -1; char *tmp_pathname = NULL; - CORE_ADDR sym_addr = 0; /* Read the contents of the .interp section into a local buffer; the contents specify the dynamic linker this program uses. */ + sym_addr = 0; interp_sect_size = bfd_section_size (exec_bfd, interp_sect); buf = alloca (interp_sect_size); bfd_get_section_contents (exec_bfd, interp_sect, @@ -1028,7 +1087,6 @@ enable_break (void) /* On a running target, we can get the dynamic linker's base address from the shared library table. */ - solib_add (NULL, 0, ¤t_target, auto_solib_add); so = master_so_list (); while (so) { @@ -1504,6 +1562,7 @@ svr4_ilp32_fetch_link_map_offsets (void) lmo.r_version_offset = 0; lmo.r_version_size = 4; lmo.r_map_offset = 4; + lmo.r_brk_offset = 8; lmo.r_ldsomap_offset = 20; /* Everything we need is in the first 20 bytes. */ @@ -1534,6 +1593,7 @@ svr4_lp64_fetch_link_map_offsets (void) lmo.r_version_offset = 0; lmo.r_version_size = 4; lmo.r_map_offset = 8; + lmo.r_brk_offset = 16; lmo.r_ldsomap_offset = 40; /* Everything we need is in the first 40 bytes. */ |