/* Handle Darwin shared libraries for GDB, the GNU Debugger.
- Copyright (C) 2009-2013 Free Software Foundation, Inc.
+ Copyright (C) 2009-2019 Free Software Foundation, Inc.
This file is part of GDB.
#include "gdbthread.h"
#include "gdb_bfd.h"
-#include "gdb_assert.h"
-
#include "solist.h"
#include "solib.h"
#include "solib-svr4.h"
#include "elf-bfd.h"
#include "exec.h"
#include "auxv.h"
-#include "exceptions.h"
#include "mach-o.h"
#include "mach-o/external.h"
/* Current all_image_infos version. */
#define DYLD_VERSION_MIN 1
-#define DYLD_VERSION_MAX 12
+#define DYLD_VERSION_MAX 15
/* Per PSPACE specific data. */
struct darwin_info
static void
darwin_pspace_data_cleanup (struct program_space *pspace, void *arg)
{
- struct darwin_info *info;
-
- info = program_space_data (pspace, solib_darwin_pspace_data);
- xfree (info);
+ xfree (arg);
}
/* Get the current darwin data. If none is found yet, add it now. This
{
struct darwin_info *info;
- info = program_space_data (current_program_space, solib_darwin_pspace_data);
+ info = (struct darwin_info *) program_space_data (current_program_space,
+ solib_darwin_pspace_data);
if (info != NULL)
return info;
- info = XZALLOC (struct darwin_info);
+ info = XCNEW (struct darwin_info);
set_program_space_data (current_program_space,
solib_darwin_pspace_data, info);
return info;
/* 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 (&info->all_image, 0, sizeof (info->all_image));
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 + ptr_type->length, ptr_type);
+ (buf + 8 + TYPE_LENGTH (ptr_type), ptr_type);
}
/* Link map info to include in an allocated so_list entry. */
-struct lm_info
+struct lm_info_darwin : public lm_info_base
{
/* The target location of lm. */
- CORE_ADDR lm_addr;
-};
-
-struct darwin_so_list
-{
- /* Common field. */
- struct so_list sl;
- /* Darwin specific data. */
- struct lm_info li;
+ CORE_ADDR lm_addr = 0;
};
/* 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;
/* 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)
Note that darwin-nat.c implements pid_to_exec_file. */
static int
-open_symbol_file_object (void *from_ttyp)
+open_symbol_file_object (int from_tty)
{
return 0;
}
CORE_ADDR path_addr;
struct mach_o_header_external hdr;
unsigned long hdr_val;
- char *file_path;
+ gdb::unique_xmalloc_ptr<char> file_path;
int errcode;
- struct darwin_so_list *dnew;
- struct so_list *new;
- struct cleanup *old_chain;
/* Read image info from inferior. */
if (target_read_memory (iinfo, buf, image_info_size))
path_addr = extract_typed_address (buf + ptr_len, ptr_type);
/* Read Mach-O header from memory. */
- if (target_read_memory (load_addr, (char *) &hdr, sizeof (hdr) - 4))
+ 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
break;
/* Create and fill the new so_list element. */
- dnew = XZALLOC (struct darwin_so_list);
- new = &dnew->sl;
- old_chain = make_cleanup (xfree, dnew);
+ gdb::unique_xmalloc_ptr<struct so_list> newobj (XCNEW (struct so_list));
- new->lm_info = &dnew->li;
+ lm_info_darwin *li = new lm_info_darwin;
+ newobj->lm_info = li;
- 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);
- xfree (file_path);
- new->lm_info->lm_addr = load_addr;
+ strncpy (newobj->so_name, file_path.get (), SO_NAME_MAX_PATH_SIZE - 1);
+ newobj->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
+ strcpy (newobj->so_original_name, newobj->so_name);
+ li->lm_addr = load_addr;
if (head == NULL)
- head = new;
+ head = newobj.get ();
else
- tail->next = new;
- tail = new;
-
- discard_cleanups (old_chain);
+ tail->next = newobj.get ();
+ tail = newobj.release ();
}
return head;
}
-/* Get the load address of the executable. We assume that the dyld info are
- correct. */
+/* 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_read_exec_load_addr (struct darwin_info *info)
+darwin_validate_exec_header (CORE_ADDR load_addr)
{
- struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr;
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;
CORE_ADDR iinfo = info->all_image.info + i * image_info_size;
gdb_byte buf[image_info_size];
CORE_ADDR load_addr;
- struct mach_o_header_external hdr;
- unsigned long hdr_val;
/* Read image info from inferior. */
if (target_read_memory (iinfo, buf, image_info_size))
break;
load_addr = extract_typed_address (buf, ptr_type);
-
- /* Read Mach-O header from memory. */
- if (target_read_memory (load_addr, (char *) &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;
- /* Check executable. */
- hdr_val = extract_unsigned_integer
- (hdr.filetype, sizeof (hdr.filetype), byte_order);
- if (hdr_val == BFD_MACH_O_MH_EXECUTE)
+ 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. */
return 0;
}
-
-/* No special symbol handling. */
-
-static void
-darwin_special_symbol_handling (void)
-{
-}
-
/* 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. */
-static bfd *
+static gdb_bfd_ref_ptr
gdb_bfd_mach_o_fat_extract (bfd *abfd, bfd_format format,
const bfd_arch_info_type *arch)
{
else
gdb_bfd_mark_parent (result, abfd);
- return result;
+ return gdb_bfd_ref_ptr (result);
}
-/* Extract dyld_all_image_addr when the process was just created, assuming the
- current PC is at the entry of the dynamic linker. */
+/* Return the BFD for the program interpreter. */
-static void
-darwin_solib_get_all_image_info_addr_at_init (struct darwin_info *info)
+static gdb_bfd_ref_ptr
+darwin_get_dyld_bfd ()
{
- gdb_byte *interp_name;
- CORE_ADDR load_addr = 0;
- bfd *dyld_bfd = NULL;
- struct cleanup *cleanup;
+ char *interp_name;
/* This method doesn't work with an attached process. */
if (current_inferior ()->attach_flag)
- return;
+ return NULL;
/* Find the program interpreter. */
interp_name = find_program_interpreter ();
if (!interp_name)
- return;
-
- cleanup = make_cleanup (null_cleanup, NULL);
+ return NULL;
/* Create a bfd for the interpreter. */
- dyld_bfd = gdb_bfd_open (interp_name, gnutarget, -1);
- if (dyld_bfd)
- {
- bfd *sub;
-
- make_cleanup_bfd_unref (dyld_bfd);
- sub = gdb_bfd_mach_o_fat_extract (dyld_bfd, bfd_object,
- gdbarch_bfd_arch_info (target_gdbarch ()));
- if (sub)
- {
- dyld_bfd = sub;
- make_cleanup_bfd_unref (sub);
- }
- else
- dyld_bfd = NULL;
- }
- if (!dyld_bfd)
+ gdb_bfd_ref_ptr dyld_bfd (gdb_bfd_open (interp_name, gnutarget, -1));
+ if (dyld_bfd != NULL)
{
- do_cleanups (cleanup);
- return;
+ gdb_bfd_ref_ptr sub
+ (gdb_bfd_mach_o_fat_extract (dyld_bfd.get (), bfd_object,
+ gdbarch_bfd_arch_info (target_gdbarch ())));
+ dyld_bfd = sub;
}
+ return dyld_bfd;
+}
+
+/* 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_get_all_image_info_addr_at_init (struct darwin_info *info)
+{
+ CORE_ADDR load_addr = 0;
+ gdb_bfd_ref_ptr dyld_bfd = darwin_get_dyld_bfd ();
+
+ if (dyld_bfd == NULL)
+ return;
/* 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));
+ - 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, "_dyld_all_image_infos");
-
- do_cleanups (cleanup);
+ 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
+/* 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 + 8 + 4];
+ gdb_byte buf[8];
LONGEST len;
- enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
+ struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr;
- len = target_read (¤t_target, TARGET_OBJECT_DARWIN_DYLD_INFO, NULL,
- buf, 0, sizeof (buf));
- if (len != sizeof (buf))
+ /* Sanity check. */
+ if (TYPE_LENGTH (ptr_type) > sizeof (buf))
return;
- info->all_image_addr = extract_unsigned_integer (buf, 8, byte_order);
+ len = target_read (current_top_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. */
darwin_load_image_infos (info);
if (!darwin_dyld_version_ok (info))
- return;
+ {
+ warning (_("unhandled dyld version (%d)"), info->all_image.version);
+ return;
+ }
- create_solib_event_breakpoint (target_gdbarch (), info->all_image.notifier);
+ 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. */
+
+ load_addr = darwin_read_exec_load_addr_at_init (info);
+ }
- /* Possible relocate the main executable (PIE). */
- load_addr = darwin_read_exec_load_addr (info);
if (load_addr != 0 && symfile_objfile != NULL)
{
- CORE_ADDR vmaddr = 0;
- struct mach_o_data_struct *md = bfd_mach_o_get_data (exec_bfd);
- unsigned int i, num;
+ CORE_ADDR vmaddr;
/* Find the base address of the executable. */
- for (i = 0; i < md->header.ncmds; i++)
- {
- struct bfd_mach_o_load_command *cmd = &md->commands[i];
-
- if (cmd->type != BFD_MACH_O_LC_SEGMENT
- && cmd->type != BFD_MACH_O_LC_SEGMENT_64)
- continue;
- if (cmd->command.segment.fileoff == 0
- && cmd->command.segment.vmaddr != 0
- && cmd->command.segment.filesize != 0)
- {
- vmaddr = cmd->command.segment.vmaddr;
- break;
- }
- }
+ vmaddr = bfd_mach_o_get_base_address (exec_bfd);
/* Relocate. */
if (vmaddr != load_addr)
objfile_rebase (symfile_objfile, load_addr - vmaddr);
}
+
+ /* Set solib notifier (to reload list of shared libraries). */
+ CORE_ADDR notifier = info->all_image.notifier;
+
+ if (info->all_image.count == 0)
+ {
+ /* Dyld hasn't yet relocated itself, so the notifier address may
+ be incorrect (as it has to be relocated). */
+ CORE_ADDR start = bfd_get_start_address (exec_bfd);
+ if (start == 0)
+ notifier = 0;
+ else
+ {
+ gdb_bfd_ref_ptr dyld_bfd = darwin_get_dyld_bfd ();
+ if (dyld_bfd != NULL)
+ {
+ CORE_ADDR dyld_bfd_start_address;
+ CORE_ADDR dyld_relocated_base_address;
+ CORE_ADDR pc;
+
+ dyld_bfd_start_address = bfd_get_start_address (dyld_bfd.get());
+
+ /* 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. */
+
+ pc = regcache_read_pc (get_current_regcache ());
+ dyld_relocated_base_address = pc - dyld_bfd_start_address;
+
+ /* We get the proper notifier relocated address by
+ adding the dyld relocated base address to the current
+ notifier offset value. */
+
+ notifier += dyld_relocated_base_address;
+ }
+ }
+ }
+
+ /* Add the breakpoint which is hit by dyld when the list of solib is
+ modified. */
+ if (notifier != 0)
+ create_solib_event_breakpoint (target_gdbarch (), notifier);
}
static void
static void
darwin_free_so (struct so_list *so)
{
+ lm_info_darwin *li = (lm_info_darwin *) so->lm_info;
+
+ delete li;
}
/* The section table is built from bfd sections using bfd VMAs.
darwin_relocate_section_addresses (struct so_list *so,
struct target_section *sec)
{
- sec->addr += so->lm_info->lm_addr;
- sec->endaddr += so->lm_info->lm_addr;
+ lm_info_darwin *li = (lm_info_darwin *) so->lm_info;
+
+ sec->addr += li->lm_addr;
+ sec->endaddr += li->lm_addr;
/* Best effort to set addr_high/addr_low. This is used only by
'info sharedlibary'. */
so->addr_low = sec->addr;
}
\f
-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 domain_enum domain)
{
- return NULL;
+ return {};
}
-static bfd *
-darwin_bfd_open (char *pathname)
+static gdb_bfd_ref_ptr
+darwin_bfd_open (const char *pathname)
{
- char *found_pathname;
int found_file;
- bfd *abfd;
- bfd *res;
/* Search for shared library file. */
- found_pathname = solib_find (pathname, &found_file);
+ gdb::unique_xmalloc_ptr<char> found_pathname
+ = solib_find (pathname, &found_file);
if (found_pathname == NULL)
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.get (), found_file));
- res = gdb_bfd_mach_o_fat_extract (abfd, bfd_object,
- gdbarch_bfd_arch_info (target_gdbarch ()));
- if (!res)
- {
- make_cleanup_bfd_unref (abfd);
- error (_("`%s': not a shared-library: %s"),
- bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ()));
- }
+ 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);
- gdb_bfd_unref (abfd);
return res;
}
struct target_so_ops darwin_so_ops;
-/* -Wmissing-prototypes */
-extern initialize_file_ftype _initialize_darwin_solib;
-
void
_initialize_darwin_solib (void)
{
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;