X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Fsolib-darwin.c;h=c507e13caf7437783adb66b09e3aa22264e18ce1;hb=434a40239548115cf04a80410e4f570f35c361c1;hp=3c700899d40db3177a45b87b43a425c9eb643d1b;hpb=268a4a75bdc5271819e657da07b868c8bddc500f;p=deliverable%2Fbinutils-gdb.git diff --git a/gdb/solib-darwin.c b/gdb/solib-darwin.c index 3c700899d4..c507e13caf 100644 --- a/gdb/solib-darwin.c +++ b/gdb/solib-darwin.c @@ -1,6 +1,6 @@ /* Handle Darwin shared libraries for GDB, the GNU Debugger. - Copyright (C) 2009, 2010 Free Software Foundation, Inc. + Copyright (C) 2009-2017 Free Software Foundation, Inc. This file is part of GDB. @@ -28,8 +28,7 @@ #include "inferior.h" #include "regcache.h" #include "gdbthread.h" - -#include "gdb_assert.h" +#include "gdb_bfd.h" #include "solist.h" #include "solib.h" @@ -39,8 +38,8 @@ #include "elf-bfd.h" #include "exec.h" #include "auxv.h" -#include "exceptions.h" #include "mach-o.h" +#include "mach-o/external.h" struct gdb_dyld_image_info { @@ -68,56 +67,88 @@ struct gdb_dyld_all_image_infos /* Current all_image_infos version. */ #define DYLD_VERSION_MIN 1 -#define DYLD_VERSION_MAX 7 +#define DYLD_VERSION_MAX 14 + +/* Per PSPACE specific data. */ +struct darwin_info +{ + /* Address of structure dyld_all_image_infos in inferior. */ + CORE_ADDR all_image_addr; + + /* Gdb copy of dyld_all_info_infos. */ + struct gdb_dyld_all_image_infos all_image; +}; -/* Address of structure dyld_all_image_infos in inferior. */ -static CORE_ADDR dyld_all_image_addr; +/* Per-program-space data key. */ +static const struct program_space_data *solib_darwin_pspace_data; -/* Gdb copy of dyld_all_info_infos. */ -static struct gdb_dyld_all_image_infos dyld_all_image; +static void +darwin_pspace_data_cleanup (struct program_space *pspace, void *arg) +{ + xfree (arg); +} + +/* Get the current darwin data. If none is found yet, add it now. This + function always returns a valid object. */ + +static struct darwin_info * +get_darwin_info (void) +{ + struct darwin_info *info; + + info = (struct darwin_info *) program_space_data (current_program_space, + solib_darwin_pspace_data); + if (info != NULL) + return info; + + info = XCNEW (struct darwin_info); + set_program_space_data (current_program_space, + solib_darwin_pspace_data, info); + return info; +} /* Return non-zero if the version in dyld_all_image is known. */ static int -darwin_dyld_version_ok (void) +darwin_dyld_version_ok (const struct darwin_info *info) { - return dyld_all_image.version >= DYLD_VERSION_MIN - && dyld_all_image.version <= DYLD_VERSION_MAX; + return info->all_image.version >= DYLD_VERSION_MIN + && info->all_image.version <= DYLD_VERSION_MAX; } /* Read dyld_all_image from inferior. */ static void -darwin_load_image_infos (void) +darwin_load_image_infos (struct darwin_info *info) { gdb_byte buf[24]; - enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch); - struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr; + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; int len; /* If the structure address is not known, don't continue. */ - if (dyld_all_image_addr == 0) + if (info->all_image_addr == 0) return; /* The structure has 4 fields: version (4 bytes), count (4 bytes), info (pointer) and notifier (pointer). */ - len = 4 + 4 + 2 * ptr_type->length; + len = 4 + 4 + 2 * TYPE_LENGTH (ptr_type); gdb_assert (len <= sizeof (buf)); - memset (&dyld_all_image, 0, sizeof (dyld_all_image)); + memset (&info->all_image, 0, sizeof (info->all_image)); /* Read structure raw bytes from target. */ - if (target_read_memory (dyld_all_image_addr, buf, len)) + if (target_read_memory (info->all_image_addr, buf, len)) return; /* Extract the fields. */ - dyld_all_image.version = extract_unsigned_integer (buf, 4, byte_order); - if (!darwin_dyld_version_ok ()) + info->all_image.version = extract_unsigned_integer (buf, 4, byte_order); + if (!darwin_dyld_version_ok (info)) return; - dyld_all_image.count = extract_unsigned_integer (buf + 4, 4, byte_order); - dyld_all_image.info = extract_typed_address (buf + 8, ptr_type); - dyld_all_image.notifier = extract_typed_address - (buf + 8 + ptr_type->length, ptr_type); + info->all_image.count = extract_unsigned_integer (buf + 4, 4, byte_order); + info->all_image.info = extract_typed_address (buf + 8, ptr_type); + info->all_image.notifier = extract_typed_address + (buf + 8 + TYPE_LENGTH (ptr_type), ptr_type); } /* Link map info to include in an allocated so_list entry. */ @@ -128,18 +159,10 @@ struct lm_info CORE_ADDR lm_addr; }; -struct darwin_so_list -{ - /* Common field. */ - struct so_list sl; - /* Darwin specific data. */ - struct lm_info li; -}; - /* Lookup the value for a specific symbol. */ static CORE_ADDR -lookup_symbol_from_bfd (bfd *abfd, char *symname) +lookup_symbol_from_bfd (bfd *abfd, const char *symname) { long storage_needed; asymbol **symbol_table; @@ -158,6 +181,7 @@ lookup_symbol_from_bfd (bfd *abfd, char *symname) for (i = 0; i < number_of_symbols; i++) { asymbol *sym = symbol_table[i]; + if (strcmp (sym->name, symname) == 0 && (sym->section->flags & (SEC_CODE | SEC_DATA)) != 0) { @@ -173,10 +197,10 @@ lookup_symbol_from_bfd (bfd *abfd, char *symname) /* Return program interpreter string. */ -static gdb_byte * +static char * find_program_interpreter (void) { - gdb_byte *buf = NULL; + char *buf = NULL; /* If we have an exec_bfd, get the interpreter from the load commands. */ if (exec_bfd) @@ -203,71 +227,88 @@ open_symbol_file_object (void *from_ttyp) return 0; } -/* Build a list of currently loaded shared objects. See solib-svr4.c */ +/* Build a list of currently loaded shared objects. See solib-svr4.c. */ static struct so_list * darwin_current_sos (void) { - struct type *ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr; + struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); int ptr_len = TYPE_LENGTH (ptr_type); unsigned int image_info_size; - CORE_ADDR lm; struct so_list *head = NULL; struct so_list *tail = NULL; int i; + struct darwin_info *info = get_darwin_info (); /* Be sure image infos are loaded. */ - darwin_load_image_infos (); + darwin_load_image_infos (info); - if (!darwin_dyld_version_ok ()) + if (!darwin_dyld_version_ok (info)) return NULL; image_info_size = ptr_len * 3; /* Read infos for each solib. - This first entry is ignored as this is the executable itself. */ - for (i = 1; i < dyld_all_image.count; i++) + The first entry was rumored to be the executable itself, but this is not + true when a large number of shared libraries are used (table expanded ?). + We now check all entries, but discard executable images. */ + for (i = 0; i < info->all_image.count; i++) { - CORE_ADDR info = dyld_all_image.info + i * image_info_size; - char buf[image_info_size]; + CORE_ADDR iinfo = info->all_image.info + i * image_info_size; + gdb_byte buf[image_info_size]; CORE_ADDR load_addr; CORE_ADDR path_addr; + struct mach_o_header_external hdr; + unsigned long hdr_val; char *file_path; int errcode; - struct darwin_so_list *dnew; - struct so_list *new; + struct so_list *newobj; struct cleanup *old_chain; /* Read image info from inferior. */ - if (target_read_memory (info, buf, image_info_size)) + if (target_read_memory (iinfo, buf, image_info_size)) break; load_addr = extract_typed_address (buf, ptr_type); path_addr = extract_typed_address (buf + ptr_len, ptr_type); + /* Read Mach-O header from memory. */ + if (target_read_memory (load_addr, (gdb_byte *) &hdr, sizeof (hdr) - 4)) + break; + /* Discard wrong magic numbers. Shouldn't happen. */ + hdr_val = extract_unsigned_integer + (hdr.magic, sizeof (hdr.magic), byte_order); + if (hdr_val != BFD_MACH_O_MH_MAGIC && hdr_val != BFD_MACH_O_MH_MAGIC_64) + continue; + /* Discard executable. Should happen only once. */ + hdr_val = extract_unsigned_integer + (hdr.filetype, sizeof (hdr.filetype), byte_order); + if (hdr_val == BFD_MACH_O_MH_EXECUTE) + continue; + target_read_string (path_addr, &file_path, SO_NAME_MAX_PATH_SIZE - 1, &errcode); if (errcode) break; /* Create and fill the new so_list element. */ - dnew = XZALLOC (struct darwin_so_list); - new = &dnew->sl; - old_chain = make_cleanup (xfree, dnew); + newobj = XCNEW (struct so_list); + old_chain = make_cleanup (xfree, newobj); - new->lm_info = &dnew->li; + newobj->lm_info = XCNEW (struct lm_info); - strncpy (new->so_name, file_path, SO_NAME_MAX_PATH_SIZE - 1); - new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; - strcpy (new->so_original_name, new->so_name); + strncpy (newobj->so_name, file_path, SO_NAME_MAX_PATH_SIZE - 1); + newobj->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; + strcpy (newobj->so_original_name, newobj->so_name); xfree (file_path); - new->lm_info->lm_addr = load_addr; + newobj->lm_info->lm_addr = load_addr; if (head == NULL) - head = new; + head = newobj; else - tail->next = new; - tail = new; + tail->next = newobj; + tail = newobj; discard_cleanups (old_chain); } @@ -275,43 +316,136 @@ darwin_current_sos (void) return head; } +/* Check LOAD_ADDR points to a Mach-O executable header. Return LOAD_ADDR + in case of success, 0 in case of failure. */ + +static CORE_ADDR +darwin_validate_exec_header (CORE_ADDR load_addr) +{ + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + struct mach_o_header_external hdr; + unsigned long hdr_val; + + /* Read Mach-O header from memory. */ + if (target_read_memory (load_addr, (gdb_byte *) &hdr, sizeof (hdr) - 4)) + return 0; + + /* Discard wrong magic numbers. Shouldn't happen. */ + hdr_val = extract_unsigned_integer + (hdr.magic, sizeof (hdr.magic), byte_order); + if (hdr_val != BFD_MACH_O_MH_MAGIC && hdr_val != BFD_MACH_O_MH_MAGIC_64) + return 0; + + /* Check executable. */ + hdr_val = extract_unsigned_integer + (hdr.filetype, sizeof (hdr.filetype), byte_order); + if (hdr_val == BFD_MACH_O_MH_EXECUTE) + return load_addr; + + return 0; +} + +/* Get the load address of the executable using dyld list of images. + We assume that the dyld info are correct (which is wrong if the target + is stopped at the first instruction). */ + +static CORE_ADDR +darwin_read_exec_load_addr_from_dyld (struct darwin_info *info) +{ + struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; + int ptr_len = TYPE_LENGTH (ptr_type); + unsigned int image_info_size = ptr_len * 3; + int i; + + /* Read infos for each solib. One of them should be the executable. */ + for (i = 0; i < info->all_image.count; i++) + { + CORE_ADDR iinfo = info->all_image.info + i * image_info_size; + gdb_byte buf[image_info_size]; + CORE_ADDR load_addr; + + /* Read image info from inferior. */ + if (target_read_memory (iinfo, buf, image_info_size)) + break; + + load_addr = extract_typed_address (buf, ptr_type); + if (darwin_validate_exec_header (load_addr) == load_addr) + return load_addr; + } + + return 0; +} + +/* Get the load address of the executable when the PC is at the dyld + entry point using parameter passed by the kernel (at SP). */ + +static CORE_ADDR +darwin_read_exec_load_addr_at_init (struct darwin_info *info) +{ + struct gdbarch *gdbarch = target_gdbarch (); + enum bfd_endian byte_order = gdbarch_byte_order (gdbarch); + int addr_size = gdbarch_addr_bit (gdbarch) / 8; + ULONGEST load_ptr_addr; + ULONGEST load_addr; + gdb_byte buf[8]; + + /* Get SP. */ + if (regcache_cooked_read_unsigned (get_current_regcache (), + gdbarch_sp_regnum (gdbarch), + &load_ptr_addr) != REG_VALID) + return 0; + + /* Read value at SP (image load address). */ + if (target_read_memory (load_ptr_addr, buf, addr_size)) + return 0; + + load_addr = extract_unsigned_integer (buf, addr_size, byte_order); + + return darwin_validate_exec_header (load_addr); +} + /* Return 1 if PC lies in the dynamic symbol resolution code of the run time loader. */ -int +static int darwin_in_dynsym_resolve_code (CORE_ADDR pc) { return 0; } +/* A wrapper for bfd_mach_o_fat_extract that handles reference + counting properly. This will either return NULL, or return a new + reference to a BFD. */ -/* No special symbol handling. */ - -static void -darwin_special_symbol_handling (void) +static gdb_bfd_ref_ptr +gdb_bfd_mach_o_fat_extract (bfd *abfd, bfd_format format, + const bfd_arch_info_type *arch) { + bfd *result = bfd_mach_o_fat_extract (abfd, format, arch); + + if (result == NULL) + return NULL; + + if (result == abfd) + gdb_bfd_ref (result); + else + gdb_bfd_mark_parent (result, abfd); + + return gdb_bfd_ref_ptr (result); } -/* Shared library startup support. See documentation in solib-svr4.c */ +/* Extract dyld_all_image_addr when the process was just created, assuming the + current PC is at the entry of the dynamic linker. */ static void -darwin_solib_create_inferior_hook (int from_tty) +darwin_solib_get_all_image_info_addr_at_init (struct darwin_info *info) { - struct minimal_symbol *msymbol; - char **bkpt_namep; - asection *interp_sect; - gdb_byte *interp_name; - CORE_ADDR sym_addr; + char *interp_name; CORE_ADDR load_addr = 0; - int load_addr_found = 0; - int loader_found_in_list = 0; - struct so_list *so; - bfd *dyld_bfd = NULL; - struct inferior *inf = current_inferior (); - /* First, remove all the solib event breakpoints. Their addresses - may have changed since the last time we ran the program. */ - remove_solib_event_breakpoints (); + /* This method doesn't work with an attached process. */ + if (current_inferior ()->attach_flag) + return; /* Find the program interpreter. */ interp_name = find_program_interpreter (); @@ -319,67 +453,131 @@ darwin_solib_create_inferior_hook (int from_tty) return; /* Create a bfd for the interpreter. */ - sym_addr = 0; - dyld_bfd = bfd_openr (interp_name, gnutarget); - if (dyld_bfd) + gdb_bfd_ref_ptr dyld_bfd (gdb_bfd_open (interp_name, gnutarget, -1)); + if (dyld_bfd != NULL) { - bfd *sub; - sub = bfd_mach_o_fat_extract (dyld_bfd, bfd_object, - gdbarch_bfd_arch_info (target_gdbarch)); - if (sub) + gdb_bfd_ref_ptr sub + (gdb_bfd_mach_o_fat_extract (dyld_bfd.get (), bfd_object, + gdbarch_bfd_arch_info (target_gdbarch ()))); + if (sub != NULL) dyld_bfd = sub; else - { - bfd_close (dyld_bfd); - dyld_bfd = NULL; - } + dyld_bfd.release (); } - if (!dyld_bfd) + if (dyld_bfd == NULL) return; - if (!inf->attach_flag) - { - /* We find the dynamic linker's base address by examining - the current pc (which should point at the entry point for the - dynamic linker) and subtracting the offset of the entry point. */ - load_addr = (regcache_read_pc (get_current_regcache ()) - - bfd_get_start_address (dyld_bfd)); - } - else + /* We find the dynamic linker's base address by examining + the current pc (which should point at the entry point for the + dynamic linker) and subtracting the offset of the entry point. */ + load_addr = (regcache_read_pc (get_current_regcache ()) + - bfd_get_start_address (dyld_bfd.get ())); + + /* Now try to set a breakpoint in the dynamic linker. */ + info->all_image_addr = + lookup_symbol_from_bfd (dyld_bfd.get (), "_dyld_all_image_infos"); + + if (info->all_image_addr == 0) + return; + + info->all_image_addr += load_addr; +} + +/* Extract dyld_all_image_addr reading it from + TARGET_OBJECT_DARWIN_DYLD_INFO. */ + +static void +darwin_solib_read_all_image_info_addr (struct darwin_info *info) +{ + gdb_byte buf[8]; + LONGEST len; + struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; + + /* Sanity check. */ + if (TYPE_LENGTH (ptr_type) > sizeof (buf)) + return; + + len = target_read (¤t_target, TARGET_OBJECT_DARWIN_DYLD_INFO, NULL, + buf, 0, TYPE_LENGTH (ptr_type)); + if (len <= 0) + return; + + /* The use of BIG endian is intended, as BUF is a raw stream of bytes. This + makes the support of remote protocol easier. */ + info->all_image_addr = extract_unsigned_integer (buf, len, BFD_ENDIAN_BIG); +} + +/* Shared library startup support. See documentation in solib-svr4.c. */ + +static void +darwin_solib_create_inferior_hook (int from_tty) +{ + struct darwin_info *info = get_darwin_info (); + CORE_ADDR load_addr; + + info->all_image_addr = 0; + + darwin_solib_read_all_image_info_addr (info); + + if (info->all_image_addr == 0) + darwin_solib_get_all_image_info_addr_at_init (info); + + if (info->all_image_addr == 0) + return; + + darwin_load_image_infos (info); + + if (!darwin_dyld_version_ok (info)) { - /* FIXME: todo. - Get address of __DATA.__dyld in exec_bfd, read address at offset 0. - */ + warning (_("unhandled dyld version (%d)"), info->all_image.version); return; } - /* Now try to set a breakpoint in the dynamic linker. */ - dyld_all_image_addr = - lookup_symbol_from_bfd (dyld_bfd, "_dyld_all_image_infos"); + /* Add the breakpoint which is hit by dyld when the list of solib is + modified. */ + create_solib_event_breakpoint (target_gdbarch (), info->all_image.notifier); - bfd_close (dyld_bfd); + if (info->all_image.count != 0) + { + /* Possible relocate the main executable (PIE). */ + load_addr = darwin_read_exec_load_addr_from_dyld (info); + } + else + { + /* Possible issue: + Do not break on the notifier if dyld is not initialized (deduced from + count == 0). In that case, dyld hasn't relocated itself and the + notifier may point to a wrong address. */ - if (dyld_all_image_addr == 0) - return; + load_addr = darwin_read_exec_load_addr_at_init (info); + } - dyld_all_image_addr += load_addr; + if (load_addr != 0 && symfile_objfile != NULL) + { + CORE_ADDR vmaddr; - darwin_load_image_infos (); + /* Find the base address of the executable. */ + vmaddr = bfd_mach_o_get_base_address (exec_bfd); - if (darwin_dyld_version_ok ()) - create_solib_event_breakpoint (target_gdbarch, dyld_all_image.notifier); + /* Relocate. */ + if (vmaddr != load_addr) + objfile_rebase (symfile_objfile, load_addr - vmaddr); + } } static void darwin_clear_solib (void) { - dyld_all_image_addr = 0; - dyld_all_image.version = 0; + struct darwin_info *info = get_darwin_info (); + + info->all_image_addr = 0; + info->all_image.version = 0; } static void darwin_free_so (struct so_list *so) { + xfree (so->lm_info); } /* The section table is built from bfd sections using bfd VMAs. @@ -405,22 +603,19 @@ darwin_relocate_section_addresses (struct so_list *so, so->addr_low = sec->addr; } -static struct symbol * -darwin_lookup_lib_symbol (const struct objfile *objfile, +static struct block_symbol +darwin_lookup_lib_symbol (struct objfile *objfile, const char *name, - const char *linkage_name, const domain_enum domain) { - return NULL; + return (struct block_symbol) {NULL, NULL}; } -static bfd * +static gdb_bfd_ref_ptr darwin_bfd_open (char *pathname) { char *found_pathname; int found_file; - bfd *abfd; - bfd *res; /* Search for shared library file. */ found_pathname = solib_find (pathname, &found_file); @@ -428,30 +623,40 @@ darwin_bfd_open (char *pathname) perror_with_name (pathname); /* Open bfd for shared library. */ - abfd = solib_bfd_fopen (found_pathname, found_file); + gdb_bfd_ref_ptr abfd (solib_bfd_fopen (found_pathname, found_file)); + + gdb_bfd_ref_ptr res + (gdb_bfd_mach_o_fat_extract (abfd.get (), bfd_object, + gdbarch_bfd_arch_info (target_gdbarch ()))); + if (res == NULL) + error (_("`%s': not a shared-library: %s"), + bfd_get_filename (abfd.get ()), bfd_errmsg (bfd_get_error ())); + + /* The current filename for fat-binary BFDs is a name generated + by BFD, usually a string containing the name of the architecture. + Reset its value to the actual filename. */ + xfree (bfd_get_filename (res.get ())); + res->filename = xstrdup (pathname); - res = bfd_mach_o_fat_extract (abfd, bfd_object, - gdbarch_bfd_arch_info (target_gdbarch)); - if (!res) - { - bfd_close (abfd); - make_cleanup (xfree, found_pathname); - error (_("`%s': not a shared-library: %s"), - found_pathname, bfd_errmsg (bfd_get_error ())); - } return res; } struct target_so_ops darwin_so_ops; +/* -Wmissing-prototypes */ +extern initialize_file_ftype _initialize_darwin_solib; + void _initialize_darwin_solib (void) { + solib_darwin_pspace_data + = register_program_space_data_with_cleanup (NULL, + darwin_pspace_data_cleanup); + darwin_so_ops.relocate_section_addresses = darwin_relocate_section_addresses; darwin_so_ops.free_so = darwin_free_so; darwin_so_ops.clear_solib = darwin_clear_solib; darwin_so_ops.solib_create_inferior_hook = darwin_solib_create_inferior_hook; - darwin_so_ops.special_symbol_handling = darwin_special_symbol_handling; darwin_so_ops.current_sos = darwin_current_sos; darwin_so_ops.open_symbol_file_object = open_symbol_file_object; darwin_so_ops.in_dynsym_resolve_code = darwin_in_dynsym_resolve_code;