diff options
| -rw-r--r-- | gdb/corelow.c | 11 | ||||
| -rw-r--r-- | gdb/linux-tdep.c | 24 | ||||
| -rw-r--r-- | gdb/solib.c | 87 | ||||
| -rw-r--r-- | gdb/solib.h | 20 |
4 files changed, 141 insertions, 1 deletions
diff --git a/gdb/corelow.c b/gdb/corelow.c index 001c4f1..c114828 100644 --- a/gdb/corelow.c +++ b/gdb/corelow.c @@ -282,6 +282,17 @@ core_target::build_file_mappings () /* Set target_section fields. */ m_core_file_mappings.emplace_back (start, end, sec); + + /* If this is a bfd of a shared library, record its soname + and build id. */ + if (build_id != nullptr) + { + gdb::unique_xmalloc_ptr<char> soname + = gdb_bfd_read_elf_soname (bfd->filename); + if (soname != nullptr) + set_cbfd_soname_build_id (current_program_space->cbfd, + soname.get (), build_id); + } }); normalize_mem_ranges (&m_core_unavailable_mappings); diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c index d486890..52cdaae 100644 --- a/gdb/linux-tdep.c +++ b/gdb/linux-tdep.c @@ -44,6 +44,7 @@ #include "solib-svr4.h" #include <ctype.h> +#include <unordered_map> /* This enum represents the values that the user can choose when informing the Linux kernel about which memory mappings will be @@ -1185,6 +1186,22 @@ linux_read_core_file_mappings if (f != descend) warning (_("malformed note - filename area is too big")); + const bfd_build_id *orig_build_id = cbfd->build_id; + std::unordered_map<ULONGEST, const bfd_build_id *> vma_map; + + /* Search for solib build-ids in the core file. Each time one is found, + map the start vma of the corresponding elf header to the build-id. */ + for (bfd_section *sec = cbfd->sections; sec != nullptr; sec = sec->next) + { + cbfd->build_id = nullptr; + + if (sec->flags & SEC_LOAD + && (get_elf_backend_data (cbfd)->elf_backend_core_find_build_id + (cbfd, (bfd_vma) sec->filepos))) + vma_map[sec->vma] = cbfd->build_id; + } + + cbfd->build_id = orig_build_id; pre_loop_cb (count); for (int i = 0; i < count; i++) @@ -1198,8 +1215,13 @@ linux_read_core_file_mappings descdata += addr_size; char * filename = filenames; filenames += strlen ((char *) filenames) + 1; + const bfd_build_id *build_id = nullptr; + auto vma_map_it = vma_map.find (start); + + if (vma_map_it != vma_map.end ()) + build_id = vma_map_it->second; - loop_cb (i, start, end, file_ofs, filename, nullptr); + loop_cb (i, start, end, file_ofs, filename, build_id); } } diff --git a/gdb/solib.c b/gdb/solib.c index 8bcbfa2..00e6c79 100644 --- a/gdb/solib.c +++ b/gdb/solib.c @@ -23,6 +23,7 @@ #include <fcntl.h> #include "symtab.h" #include "bfd.h" +#include "build-id.h" #include "symfile.h" #include "objfiles.h" #include "gdbcore.h" @@ -519,6 +520,55 @@ solib_bfd_open (const char *pathname) return abfd; } +/* Mapping of a core file's shared library sonames to their respective + build-ids. Added to the registries of core file bfds. */ + +typedef std::unordered_map<std::string, std::string> soname_build_id_map; + +/* Key used to associate a soname_build_id_map to a core file bfd. */ + +static const struct bfd_key<soname_build_id_map> cbfd_soname_build_id_data_key; + +/* See solib.h. */ + +void +set_cbfd_soname_build_id (gdb_bfd_ref_ptr abfd, + const char *soname, + const bfd_build_id *build_id) +{ + gdb_assert (abfd.get () != nullptr); + gdb_assert (soname != nullptr); + gdb_assert (build_id != nullptr); + + soname_build_id_map *mapptr = cbfd_soname_build_id_data_key.get (abfd.get ()); + + if (mapptr == nullptr) + mapptr = cbfd_soname_build_id_data_key.emplace (abfd.get ()); + + (*mapptr)[soname] = build_id_to_string (build_id); +} + +/* See solib.h. */ + +gdb::unique_xmalloc_ptr<char> +get_cbfd_soname_build_id (gdb_bfd_ref_ptr abfd, const char *soname) +{ + if (abfd.get () == nullptr || soname == nullptr) + return {}; + + soname_build_id_map *mapptr + = cbfd_soname_build_id_data_key.get (abfd.get ()); + + if (mapptr == nullptr) + return {}; + + auto it = mapptr->find (lbasename (soname)); + if (it == mapptr->end ()) + return {}; + + return make_unique_xstrdup (it->second.c_str ()); +} + /* Given a pointer to one of the shared objects in our list of mapped objects, use the recorded name to open a bfd descriptor for the object, build a section table, relocate all the section addresses @@ -1586,6 +1636,43 @@ gdb_bfd_scan_elf_dyntag (const int desired_dyntag, bfd *abfd, CORE_ADDR *ptr, return 0; } +/* See solib.h. */ + +gdb::unique_xmalloc_ptr<char> +gdb_bfd_read_elf_soname (const char *filename) +{ + gdb_bfd_ref_ptr abfd = gdb_bfd_open (filename, gnutarget); + + if (abfd == nullptr) + return {}; + + /* Check that ABFD is an ET_DYN ELF file. */ + if (!bfd_check_format (abfd.get (), bfd_object) + || !(bfd_get_file_flags (abfd.get ()) & DYNAMIC)) + return {}; + + CORE_ADDR idx; + if (!gdb_bfd_scan_elf_dyntag (DT_SONAME, abfd.get (), &idx, nullptr)) + return {}; + + struct bfd_section *dynstr = bfd_get_section_by_name (abfd.get (), ".dynstr"); + int sect_size = bfd_section_size (dynstr); + if (dynstr == nullptr || sect_size <= idx) + return {}; + + /* Read soname from the string table. */ + gdb::byte_vector dynstr_buf; + if (!gdb_bfd_get_full_section_contents (abfd.get (), dynstr, &dynstr_buf)) + return {}; + + /* Ensure soname is null-terminated before returning a copy. */ + char *soname = (char *) dynstr_buf.data () + idx; + if (strnlen (soname, sect_size - idx) == sect_size - idx) + return {}; + + return make_unique_xstrdup (soname); +} + /* Lookup the value for a specific symbol from symbol table. Look up symbol from ABFD. MATCH_SYM is a callback function to determine whether to pick up a symbol. DATA is the input of this callback function. Return NULL diff --git a/gdb/solib.h b/gdb/solib.h index 2258b0b..cd6c8a8 100644 --- a/gdb/solib.h +++ b/gdb/solib.h @@ -118,6 +118,12 @@ extern CORE_ADDR gdb_bfd_lookup_symbol_from_symtab (bfd *abfd, extern int gdb_bfd_scan_elf_dyntag (const int desired_dyntag, bfd *abfd, CORE_ADDR *ptr, CORE_ADDR *ptr_addr); +/* If FILENAME refers to an ELF shared object then attempt to return the + string referred to by its DT_SONAME tag. */ + +extern gdb::unique_xmalloc_ptr<char> gdb_bfd_read_elf_soname + (const char *filename); + /* Enable or disable optional solib event breakpoints as appropriate. */ extern void update_solib_breakpoints (void); @@ -126,4 +132,18 @@ extern void update_solib_breakpoints (void); extern void handle_solib_event (void); +/* Associate SONAME with BUILD_ID in ABFD's registry so that it can be + retrieved with get_cbfd_soname_build_id. */ + +extern void set_cbfd_soname_build_id (gdb_bfd_ref_ptr abfd, + const char *soname, + const bfd_build_id *build_id); + +/* If SONAME had a build-id associated with it in ABFD's registry by a + previous call to set_cbfd_soname_build_id then return the build-id + as a NULL-terminated hex string. */ + +extern gdb::unique_xmalloc_ptr<char> get_cbfd_soname_build_id + (gdb_bfd_ref_ptr abfd, const char *soname); + #endif /* SOLIB_H */ |