/* Core dump and executable file functions below target vector, for GDB.
- Copyright (C) 1986-2018 Free Software Foundation, Inc.
+ Copyright (C) 1986-2021 Free Software Foundation, Inc.
This file is part of GDB.
#include "arch-utils.h"
#include <signal.h>
#include <fcntl.h>
-#ifdef HAVE_SYS_FILE_H
-#include <sys/file.h> /* needed for F_OK and friends */
-#endif
#include "frame.h" /* required by inferior.h */
#include "inferior.h"
#include "infrun.h"
#include "command.h"
#include "bfd.h"
#include "target.h"
+#include "process-stratum-target.h"
#include "gdbcore.h"
#include "gdbthread.h"
#include "regcache.h"
#include "regset.h"
#include "symfile.h"
#include "exec.h"
-#include "readline/readline.h"
+#include "readline/tilde.h"
#include "solib.h"
+#include "solist.h"
#include "filenames.h"
#include "progspace.h"
#include "objfiles.h"
#include "gdb_bfd.h"
#include "completer.h"
-#include "filestuff.h"
+#include "gdbsupport/filestuff.h"
+#include "build-id.h"
+#include "gdbsupport/pathstuff.h"
+#include <unordered_map>
+#include <unordered_set>
+#include "gdbcmd.h"
+#include "xml-tdesc.h"
#ifndef O_LARGEFILE
#define O_LARGEFILE 0
#endif
-static core_fns *sniff_core_bfd (gdbarch *core_gdbarch,
- bfd *abfd);
-
/* The core file target. */
static const target_info core_target_info = {
"core",
N_("Local core dump file"),
- N_("Use a core file as a target. Specify the filename of the core file.")
+ N_("Use a core file as a target.\n\
+Specify the filename of the core file.")
};
-class core_target final : public target_ops
+class core_target final : public process_stratum_target
{
public:
core_target ();
- ~core_target () override;
const target_info &info () const override
{ return core_target_info; }
bool thread_alive (ptid_t ptid) override;
const struct target_desc *read_description () override;
- const char *pid_to_str (ptid_t) override;
+ std::string pid_to_str (ptid_t) override;
const char *thread_name (struct thread_info *) override;
+ bool has_all_memory () override { return true; }
bool has_memory () override;
bool has_stack () override;
bool has_registers () override;
+ bool has_execution (inferior *inf) override { return false; }
+
bool info_proc (const char *, enum info_proc_what) override;
/* A few helpers. */
void get_core_register_section (struct regcache *regcache,
const struct regset *regset,
const char *name,
- int min_size,
- int which,
+ int section_min_size,
const char *human_name,
bool required);
+ /* See definition. */
+ void info_proc_mappings (struct gdbarch *gdbarch);
+
private: /* per-core data */
/* The core's section table. Note that these target sections are
shared library bfds. The core bfd sections are an implementation
detail of the core target, just like ptrace is for unix child
targets. */
- target_section_table m_core_section_table {};
+ target_section_table m_core_section_table;
+
+ /* File-backed address space mappings: some core files include
+ information about memory mapped files. */
+ target_section_table m_core_file_mappings;
- /* The core_fns for a core file handler that is prepared to read the
- core file currently open on core_bfd. */
- core_fns *m_core_vec = NULL;
+ /* Unavailable mappings. These correspond to pathnames which either
+ weren't found or could not be opened. Knowing these addresses can
+ still be useful. */
+ std::vector<mem_range> m_core_unavailable_mappings;
+
+ /* Build m_core_file_mappings. Called from the constructor. */
+ void build_file_mappings ();
+
+ /* Helper method for xfer_partial. */
+ enum target_xfer_status xfer_memory_via_mappings (gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset,
+ ULONGEST len,
+ ULONGEST *xfered_len);
/* FIXME: kettenis/20031023: Eventually this field should
disappear. */
core_target::core_target ()
{
- to_stratum = process_stratum;
-
+ /* Find a first arch based on the BFD. We need the initial gdbarch so
+ we can setup the hooks to find a target description. */
m_core_gdbarch = gdbarch_from_bfd (core_bfd);
- /* Find a suitable core file handler to munch on core_bfd */
- m_core_vec = sniff_core_bfd (m_core_gdbarch, core_bfd);
+ /* If the arch is able to read a target description from the core, it
+ could yield a more specific gdbarch. */
+ const struct target_desc *tdesc = read_description ();
- /* Find the data section */
- if (build_section_table (core_bfd,
- &m_core_section_table.sections,
- &m_core_section_table.sections_end))
- error (_("\"%s\": Can't find sections: %s"),
- bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ()));
-}
-
-core_target::~core_target ()
-{
- xfree (m_core_section_table.sections);
-}
-
-/* List of all available core_fns. On gdb startup, each core file
- register reader calls deprecated_add_core_fns() to register
- information on each core format it is prepared to read. */
-
-static struct core_fns *core_file_fns = NULL;
-
-static int gdb_check_format (bfd *);
-
-static void add_to_thread_list (bfd *, asection *, void *);
-
-/* An arbitrary identifier for the core inferior. */
-#define CORELOW_PID 1
-
-/* Link a new core_fns into the global core_file_fns list. Called on
- gdb startup by the _initialize routine in each core file register
- reader, to register information about each format the reader is
- prepared to handle. */
-
-void
-deprecated_add_core_fns (struct core_fns *cf)
-{
- cf->next = core_file_fns;
- core_file_fns = cf;
-}
+ if (tdesc != nullptr)
+ {
+ struct gdbarch_info info;
+ info.abfd = core_bfd;
+ info.target_desc = tdesc;
+ m_core_gdbarch = gdbarch_find_by_info (info);
+ }
-/* The default function that core file handlers can use to examine a
- core file BFD and decide whether or not to accept the job of
- reading the core file. */
+ if (!m_core_gdbarch
+ || !gdbarch_iterate_over_regset_sections_p (m_core_gdbarch))
+ error (_("\"%s\": Core file format not supported"),
+ bfd_get_filename (core_bfd));
-int
-default_core_sniffer (struct core_fns *our_fns, bfd *abfd)
-{
- int result;
+ /* Find the data section */
+ m_core_section_table = build_section_table (core_bfd);
- result = (bfd_get_flavour (abfd) == our_fns -> core_flavour);
- return (result);
+ build_file_mappings ();
}
-/* Walk through the list of core functions to find a set that can
- handle the core file open on ABFD. Returns pointer to set that is
- selected. */
-
-static struct core_fns *
-sniff_core_bfd (struct gdbarch *core_gdbarch, bfd *abfd)
-{
- struct core_fns *cf;
- struct core_fns *yummy = NULL;
- int matches = 0;
-
- /* Don't sniff if we have support for register sets in
- CORE_GDBARCH. */
- if (core_gdbarch && gdbarch_iterate_over_regset_sections_p (core_gdbarch))
- return NULL;
-
- for (cf = core_file_fns; cf != NULL; cf = cf->next)
- {
- if (cf->core_sniffer (cf, abfd))
- {
- yummy = cf;
- matches++;
- }
- }
- if (matches > 1)
- {
- warning (_("\"%s\": ambiguous core format, %d handlers match"),
- bfd_get_filename (abfd), matches);
- }
- else if (matches == 0)
- error (_("\"%s\": no core file handler recognizes format"),
- bfd_get_filename (abfd));
+/* Construct the target_section_table for file-backed mappings if
+ they exist.
- return (yummy);
-}
+ For each unique path in the note, we'll open a BFD with a bfd
+ target of "binary". This is an unstructured bfd target upon which
+ we'll impose a structure from the mappings in the architecture-specific
+ mappings note. A BFD section is allocated and initialized for each
+ file-backed mapping.
-/* The default is to reject every core file format we see. Either
- BFD has to recognize it, or we have to provide a function in the
- core file handler that recognizes it. */
+ We take care to not share already open bfds with other parts of
+ GDB; in particular, we don't want to add new sections to existing
+ BFDs. We do, however, ensure that the BFDs that we allocate here
+ will go away (be deallocated) when the core target is detached. */
-int
-default_check_format (bfd *abfd)
+void
+core_target::build_file_mappings ()
{
- return (0);
+ std::unordered_map<std::string, struct bfd *> bfd_map;
+ std::unordered_set<std::string> unavailable_paths;
+
+ /* See linux_read_core_file_mappings() in linux-tdep.c for an example
+ read_core_file_mappings method. */
+ gdbarch_read_core_file_mappings (m_core_gdbarch, core_bfd,
+
+ /* After determining the number of mappings, read_core_file_mappings
+ will invoke this lambda. */
+ [&] (ULONGEST)
+ {
+ },
+
+ /* read_core_file_mappings will invoke this lambda for each mapping
+ that it finds. */
+ [&] (int num, ULONGEST start, ULONGEST end, ULONGEST file_ofs,
+ const char *filename)
+ {
+ /* Architecture-specific read_core_mapping methods are expected to
+ weed out non-file-backed mappings. */
+ gdb_assert (filename != nullptr);
+
+ struct bfd *bfd = bfd_map[filename];
+ if (bfd == nullptr)
+ {
+ /* Use exec_file_find() to do sysroot expansion. It'll
+ also strip the potential sysroot "target:" prefix. If
+ there is no sysroot, an equivalent (possibly more
+ canonical) pathname will be provided. */
+ gdb::unique_xmalloc_ptr<char> expanded_fname
+ = exec_file_find (filename, NULL);
+ if (expanded_fname == nullptr)
+ {
+ m_core_unavailable_mappings.emplace_back (start, end - start);
+ /* Print just one warning per path. */
+ if (unavailable_paths.insert (filename).second)
+ warning (_("Can't open file %s during file-backed mapping "
+ "note processing"),
+ filename);
+ return;
+ }
+
+ bfd = bfd_map[filename] = bfd_openr (expanded_fname.get (),
+ "binary");
+
+ if (bfd == nullptr || !bfd_check_format (bfd, bfd_object))
+ {
+ m_core_unavailable_mappings.emplace_back (start, end - start);
+ /* If we get here, there's a good chance that it's due to
+ an internal error. We issue a warning instead of an
+ internal error because of the possibility that the
+ file was removed in between checking for its
+ existence during the expansion in exec_file_find()
+ and the calls to bfd_openr() / bfd_check_format().
+ Output both the path from the core file note along
+ with its expansion to make debugging this problem
+ easier. */
+ warning (_("Can't open file %s which was expanded to %s "
+ "during file-backed mapping note processing"),
+ filename, expanded_fname.get ());
+ if (bfd != nullptr)
+ bfd_close (bfd);
+ return;
+ }
+ /* Ensure that the bfd will be closed when core_bfd is closed.
+ This can be checked before/after a core file detach via
+ "maint info bfds". */
+ gdb_bfd_record_inclusion (core_bfd, bfd);
+ }
+
+ /* Make new BFD section. All sections have the same name,
+ which is permitted by bfd_make_section_anyway(). */
+ asection *sec = bfd_make_section_anyway (bfd, "load");
+ if (sec == nullptr)
+ error (_("Can't make section"));
+ sec->filepos = file_ofs;
+ bfd_set_section_flags (sec, SEC_READONLY | SEC_HAS_CONTENTS);
+ bfd_set_section_size (sec, end - start);
+ bfd_set_section_vma (sec, start);
+ bfd_set_section_lma (sec, start);
+ bfd_set_section_alignment (sec, 2);
+
+ /* Set target_section fields. */
+ m_core_file_mappings.emplace_back (start, end, sec);
+ });
+
+ normalize_mem_ranges (&m_core_unavailable_mappings);
}
-/* Attempt to recognize core file formats that BFD rejects. */
-
-static int
-gdb_check_format (bfd *abfd)
-{
- struct core_fns *cf;
-
- for (cf = core_file_fns; cf != NULL; cf = cf->next)
- {
- if (cf->check_format (abfd))
- {
- return (1);
- }
- }
- return (0);
-}
+/* An arbitrary identifier for the core inferior. */
+#define CORELOW_PID 1
/* Close the core target. */
{
if (core_bfd)
{
- int pid = ptid_get_pid (inferior_ptid);
- inferior_ptid = null_ptid; /* Avoid confusion from thread
- stuff. */
- if (pid != 0)
- exit_inferior_silent (pid);
+ switch_to_no_thread (); /* Avoid confusion from thread
+ stuff. */
+ exit_inferior_silent (current_inferior ());
/* Clear out solib state while the bfd is still open. See
- comments in clear_solib in solib.c. */
+ comments in clear_solib in solib.c. */
clear_solib ();
current_program_space->cbfd.reset (nullptr);
extract the list of threads in a core file. */
static void
-add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
+add_to_thread_list (asection *asect, asection *reg_sect)
{
- ptid_t ptid;
int core_tid;
int pid, lwpid;
- asection *reg_sect = (asection *) reg_sect_arg;
- int fake_pid_p = 0;
+ bool fake_pid_p = false;
struct inferior *inf;
- if (!startswith (bfd_section_name (abfd, asect), ".reg/"))
+ if (!startswith (bfd_section_name (asect), ".reg/"))
return;
- core_tid = atoi (bfd_section_name (abfd, asect) + 5);
+ core_tid = atoi (bfd_section_name (asect) + 5);
pid = bfd_core_file_pid (core_bfd);
if (pid == 0)
{
- fake_pid_p = 1;
+ fake_pid_p = true;
pid = CORELOW_PID;
}
inf->fake_pid_p = fake_pid_p;
}
- ptid = ptid_build (pid, lwpid, 0);
+ ptid_t ptid (pid, lwpid);
- add_thread (ptid);
+ thread_info *thr = add_thread (inf->process_target (), ptid);
/* Warning, Will Robinson, looking at BFD private data! */
if (reg_sect != NULL
&& asect->filepos == reg_sect->filepos) /* Did we find .reg? */
- inferior_ptid = ptid; /* Yes, make it current. */
+ switch_to_thread (thr); /* Yes, make it current. */
}
/* Issue a message saying we have no core to debug, if FROM_TTY. */
printf_filtered (_("No core file now.\n"));
}
-/* Backward compatability with old way of specifying core files. */
+/* Backward compatibility with old way of specifying core files. */
void
core_file_command (const char *filename, int from_tty)
core_target_open (filename, from_tty);
}
+/* Locate (and load) an executable file (and symbols) given the core file
+ BFD ABFD. */
+
+static void
+locate_exec_from_corefile_build_id (bfd *abfd, int from_tty)
+{
+ const bfd_build_id *build_id = build_id_bfd_get (abfd);
+ if (build_id == nullptr)
+ return;
+
+ gdb_bfd_ref_ptr execbfd
+ = build_id_to_exec_bfd (build_id->size, build_id->data);
+
+ if (execbfd != nullptr)
+ {
+ exec_file_attach (bfd_get_filename (execbfd.get ()), from_tty);
+ symbol_file_add_main (bfd_get_filename (execbfd.get ()),
+ symfile_add_flag (from_tty ? SYMFILE_VERBOSE : 0));
+ }
+}
+
/* See gdbcore.h. */
void
{
const char *p;
int siggy;
- struct cleanup *old_chain;
int scratch_chan;
int flags;
gdb::unique_xmalloc_ptr<char> filename (tilde_expand (arg));
if (!IS_ABSOLUTE_PATH (filename.get ()))
- filename.reset (concat (current_directory, "/",
- filename.get (), (char *) NULL));
+ filename = gdb_abspath (filename.get ());
flags = O_BINARY | O_LARGEFILE;
if (write_files)
if (temp_bfd == NULL)
perror_with_name (filename.get ());
- if (!bfd_check_format (temp_bfd.get (), bfd_core)
- && !gdb_check_format (temp_bfd.get ()))
+ if (!bfd_check_format (temp_bfd.get (), bfd_core))
{
/* Do it after the err msg */
/* FIXME: should be checking for errors from bfd_close (for one
- thing, on error it does not free all the storage associated
- with the bfd). */
+ thing, on error it does not free all the storage associated
+ with the bfd). */
error (_("\"%s\" is not a core dump: %s"),
filename.get (), bfd_errmsg (bfd_get_error ()));
}
core file. We don't do this unconditionally since an exec file
typically contains more information that helps us determine the
architecture than a core file. */
- if (!exec_bfd)
+ if (!current_program_space->exec_bfd ())
set_gdbarch_from_file (core_bfd);
- push_target (target);
- target_holder.release ();
+ current_inferior ()->push_target (std::move (target_holder));
- /* Do this before acknowledging the inferior, so if
- post_create_inferior throws (can happen easilly if you're loading
- a core file with the wrong exec), we aren't left with threads
- from the previous inferior. */
- init_thread_list ();
-
- inferior_ptid = null_ptid;
+ switch_to_no_thread ();
/* Need to flush the register cache (and the frame cache) from a
previous debug session. If inferior_ptid ends up the same as the
/* Build up thread list from BFD sections, and possibly set the
current thread to the .reg/NN section matching the .reg
section. */
- bfd_map_over_sections (core_bfd, add_to_thread_list,
- bfd_get_section_by_name (core_bfd, ".reg"));
+ asection *reg_sect = bfd_get_section_by_name (core_bfd, ".reg");
+ for (asection *sect : gdb_bfd_sections (core_bfd))
+ add_to_thread_list (sect, reg_sect);
- if (ptid_equal (inferior_ptid, null_ptid))
+ if (inferior_ptid == null_ptid)
{
/* Either we found no .reg/NN section, and hence we have a
non-threaded core (single-threaded, from gdb's perspective),
which was the "main" thread. The latter case shouldn't
usually happen, but we're dealing with input here, which can
always be broken in different ways. */
- struct thread_info *thread = first_thread_of_process (-1);
+ thread_info *thread = first_thread_of_inferior (current_inferior ());
if (thread == NULL)
{
inferior_appeared (current_inferior (), CORELOW_PID);
- inferior_ptid = pid_to_ptid (CORELOW_PID);
- add_thread_silent (inferior_ptid);
+ thread = add_thread_silent (target, ptid_t (CORELOW_PID));
}
- else
- switch_to_thread (thread->ptid);
+
+ switch_to_thread (thread);
}
- post_create_inferior (target, from_tty);
+ if (current_program_space->exec_bfd () == nullptr)
+ locate_exec_from_corefile_build_id (core_bfd, from_tty);
+
+ post_create_inferior (from_tty);
/* Now go through the target stack looking for threads since there
may be a thread_stratum target loaded on top of target core by
now. The layer above should claim threads found in the BFD
sections. */
- TRY
+ try
{
target_update_thread_list ();
}
- CATCH (except, RETURN_MASK_ERROR)
+ catch (const gdb_exception_error &except)
{
exception_print (gdb_stderr, except);
}
- END_CATCH
p = bfd_core_file_failing_command (core_bfd);
if (p)
siggy)
: gdb_signal_from_host (siggy));
- printf_filtered (_("Program terminated with signal %s, %s.\n"),
+ printf_filtered (_("Program terminated with signal %s, %s"),
gdb_signal_to_name (sig), gdb_signal_to_string (sig));
+ if (gdbarch_report_signal_info_p (core_gdbarch))
+ gdbarch_report_signal_info (core_gdbarch, current_uiout, sig);
+ printf_filtered (_(".\n"));
/* Set the value of the internal variable $_exitsignal,
which holds the signal uncaught by the inferior. */
/* Current thread should be NUM 1 but the user does not know that.
If a program is single threaded gdb in general does not mention
anything about threads. That is why the test is >= 2. */
- if (thread_count () >= 2)
+ if (thread_count (target) >= 2)
{
- TRY
+ try
{
thread_command (NULL, from_tty);
}
- CATCH (except, RETURN_MASK_ERROR)
+ catch (const gdb_exception_error &except)
{
exception_print (gdb_stderr, except);
}
- END_CATCH
}
}
/* Note that 'this' is dangling after this call. unpush_target
closes the target, and our close implementation deletes
'this'. */
- unpush_target (this);
+ inf->unpush_target (this);
+ /* Clear the register cache and the frame cache. */
+ registers_changed ();
reinit_frame_cache ();
maybe_say_no_core_file_now (from_tty);
}
/* Try to retrieve registers from a section in core_bfd, and supply
- them to m_core_vec->core_read_registers, as the register set
- numbered WHICH.
+ them to REGSET.
If ptid's lwp member is zero, do the single-threaded
thing: look for a section named NAME. If ptid's lwp
core_target::get_core_register_section (struct regcache *regcache,
const struct regset *regset,
const char *name,
- int min_size,
- int which,
+ int section_min_size,
const char *human_name,
bool required)
{
+ gdb_assert (regset != nullptr);
+
struct bfd_section *section;
bfd_size_type size;
- char *contents;
- bool variable_size_section = (regset != NULL
- && regset->flags & REGSET_VARIABLE_SIZE);
+ bool variable_size_section = (regset->flags & REGSET_VARIABLE_SIZE);
thread_section_name section_name (name, regcache->ptid ());
return;
}
- size = bfd_section_size (core_bfd, section);
- if (size < min_size)
+ size = bfd_section_size (section);
+ if (size < section_min_size)
{
warning (_("Section `%s' in core file too small."),
section_name.c_str ());
return;
}
- if (size != min_size && !variable_size_section)
+ if (size != section_min_size && !variable_size_section)
{
warning (_("Unexpected size of section `%s' in core file."),
section_name.c_str ());
}
- contents = (char *) alloca (size);
- if (! bfd_get_section_contents (core_bfd, section, contents,
- (file_ptr) 0, size))
+ gdb::byte_vector contents (size);
+ if (!bfd_get_section_contents (core_bfd, section, contents.data (),
+ (file_ptr) 0, size))
{
warning (_("Couldn't read %s registers from `%s' section in core file."),
human_name, section_name.c_str ());
return;
}
- if (regset != NULL)
- {
- regset->supply_regset (regset, regcache, -1, contents, size);
- return;
- }
-
- gdb_assert (m_core_vec != nullptr);
- m_core_vec->core_read_registers (regcache, contents, size, which,
- ((CORE_ADDR)
- bfd_section_vma (core_bfd, section)));
+ regset->supply_regset (regset, regcache, -1, contents.data (), size);
}
/* Data passed to gdbarch_iterate_over_regset_sections's callback. */
register note section. */
static void
-get_core_registers_cb (const char *sect_name, int size,
+get_core_registers_cb (const char *sect_name, int supply_size, int collect_size,
const struct regset *regset,
const char *human_name, void *cb_data)
{
+ gdb_assert (regset != nullptr);
+
auto *data = (get_core_registers_cb_data *) cb_data;
bool required = false;
+ bool variable_size_section = (regset->flags & REGSET_VARIABLE_SIZE);
+
+ if (!variable_size_section)
+ gdb_assert (supply_size == collect_size);
if (strcmp (sect_name, ".reg") == 0)
{
human_name = "floating-point";
}
- /* The 'which' parameter is only used when no regset is provided.
- Thus we just set it to -1. */
data->target->get_core_register_section (data->regcache, regset, sect_name,
- size, -1, human_name, required);
+ supply_size, human_name, required);
}
/* Get the registers out of a core file. This is the machine-
void
core_target::fetch_registers (struct regcache *regcache, int regno)
{
- int i;
- struct gdbarch *gdbarch;
-
if (!(m_core_gdbarch != nullptr
- && gdbarch_iterate_over_regset_sections_p (m_core_gdbarch))
- && (m_core_vec == NULL || m_core_vec->core_read_registers == NULL))
+ && gdbarch_iterate_over_regset_sections_p (m_core_gdbarch)))
{
fprintf_filtered (gdb_stderr,
"Can't fetch registers from this type of core file\n");
return;
}
- gdbarch = regcache->arch ();
- if (gdbarch_iterate_over_regset_sections_p (gdbarch))
- {
- get_core_registers_cb_data data = { this, regcache };
- gdbarch_iterate_over_regset_sections (gdbarch,
- get_core_registers_cb,
- (void *) &data, NULL);
- }
- else
- {
- get_core_register_section (regcache, NULL,
- ".reg", 0, 0, "general-purpose", 1);
- get_core_register_section (regcache, NULL,
- ".reg2", 0, 2, "floating-point", 0);
- }
+ struct gdbarch *gdbarch = regcache->arch ();
+ get_core_registers_cb_data data = { this, regcache };
+ gdbarch_iterate_over_regset_sections (gdbarch,
+ get_core_registers_cb,
+ (void *) &data, NULL);
/* Mark all registers not found in the core as unavailable. */
- for (i = 0; i < gdbarch_num_regs (regcache->arch ()); i++)
+ for (int i = 0; i < gdbarch_num_regs (regcache->arch ()); i++)
if (regcache->get_register_status (i) == REG_UNKNOWN)
regcache->raw_supply (i, NULL);
}
print_section_info (&m_core_section_table, core_bfd);
}
\f
-struct spuid_list
-{
- gdb_byte *buf;
- ULONGEST offset;
- LONGEST len;
- ULONGEST pos;
- ULONGEST written;
-};
+/* Helper method for core_target::xfer_partial. */
-static void
-add_to_spuid_list (bfd *abfd, asection *asect, void *list_p)
+enum target_xfer_status
+core_target::xfer_memory_via_mappings (gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, ULONGEST len,
+ ULONGEST *xfered_len)
{
- struct spuid_list *list = (struct spuid_list *) list_p;
- enum bfd_endian byte_order
- = bfd_big_endian (abfd) ? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE;
- int fd, pos = 0;
+ enum target_xfer_status xfer_status;
- sscanf (bfd_section_name (abfd, asect), "SPU/%d/regs%n", &fd, &pos);
- if (pos == 0)
- return;
+ xfer_status = (section_table_xfer_memory_partial
+ (readbuf, writebuf,
+ offset, len, xfered_len,
+ m_core_file_mappings));
+
+ if (xfer_status == TARGET_XFER_OK || m_core_unavailable_mappings.empty ())
+ return xfer_status;
+
+ /* There are instances - e.g. when debugging within a docker
+ container using the AUFS storage driver - where the pathnames
+ obtained from the note section are incorrect. Despite the path
+ being wrong, just knowing the start and end addresses of the
+ mappings is still useful; we can attempt an access of the file
+ stratum constrained to the address ranges corresponding to the
+ unavailable mappings. */
+
+ ULONGEST memaddr = offset;
+ ULONGEST memend = offset + len;
- if (list->pos >= list->offset && list->pos + 4 <= list->offset + list->len)
+ for (const auto &mr : m_core_unavailable_mappings)
{
- store_unsigned_integer (list->buf + list->pos - list->offset,
- 4, byte_order, fd);
- list->written += 4;
+ if (address_in_mem_range (memaddr, &mr))
+ {
+ if (!address_in_mem_range (memend, &mr))
+ len = mr.start + mr.length - memaddr;
+
+ xfer_status = this->beneath ()->xfer_partial (TARGET_OBJECT_MEMORY,
+ NULL,
+ readbuf,
+ writebuf,
+ offset,
+ len,
+ xfered_len);
+ break;
+ }
}
- list->pos += 4;
+
+ return xfer_status;
}
enum target_xfer_status
switch (object)
{
case TARGET_OBJECT_MEMORY:
- return (section_table_xfer_memory_partial
- (readbuf, writebuf,
- offset, len, xfered_len,
- m_core_section_table.sections,
- m_core_section_table.sections_end,
- NULL));
+ {
+ enum target_xfer_status xfer_status;
+
+ /* Try accessing memory contents from core file data,
+ restricting consideration to those sections for which
+ the BFD section flag SEC_HAS_CONTENTS is set. */
+ auto has_contents_cb = [] (const struct target_section *s)
+ {
+ return ((s->the_bfd_section->flags & SEC_HAS_CONTENTS) != 0);
+ };
+ xfer_status = section_table_xfer_memory_partial
+ (readbuf, writebuf,
+ offset, len, xfered_len,
+ m_core_section_table,
+ has_contents_cb);
+ if (xfer_status == TARGET_XFER_OK)
+ return TARGET_XFER_OK;
+ /* Check file backed mappings. If they're available, use
+ core file provided mappings (e.g. from .note.linuxcore.file
+ or the like) as this should provide a more accurate
+ result. If not, check the stratum beneath us, which should
+ be the file stratum.
+
+ We also check unavailable mappings due to Docker/AUFS driver
+ issues. */
+ if (!m_core_file_mappings.empty ()
+ || !m_core_unavailable_mappings.empty ())
+ {
+ xfer_status = xfer_memory_via_mappings (readbuf, writebuf, offset,
+ len, xfered_len);
+ }
+ else
+ xfer_status = this->beneath ()->xfer_partial (object, annex, readbuf,
+ writebuf, offset, len,
+ xfered_len);
+ if (xfer_status == TARGET_XFER_OK)
+ return TARGET_XFER_OK;
+
+ /* Finally, attempt to access data in core file sections with
+ no contents. These will typically read as all zero. */
+ auto no_contents_cb = [&] (const struct target_section *s)
+ {
+ return !has_contents_cb (s);
+ };
+ xfer_status = section_table_xfer_memory_partial
+ (readbuf, writebuf,
+ offset, len, xfered_len,
+ m_core_section_table,
+ no_contents_cb);
+
+ return xfer_status;
+ }
case TARGET_OBJECT_AUXV:
if (readbuf)
{
if (section == NULL)
return TARGET_XFER_E_IO;
- size = bfd_section_size (core_bfd, section);
+ size = bfd_section_size (section);
if (offset >= size)
return TARGET_XFER_EOF;
size -= offset;
if (section == NULL)
return TARGET_XFER_E_IO;
- size = bfd_section_size (core_bfd, section);
+ size = bfd_section_size (section);
if (offset >= size)
return TARGET_XFER_EOF;
size -= offset;
}
/* FALL THROUGH */
- case TARGET_OBJECT_SPU:
- if (readbuf && annex)
- {
- /* When the SPU contexts are stored in a core file, BFD
- represents this with a fake section called
- "SPU/<annex>". */
-
- struct bfd_section *section;
- bfd_size_type size;
- char sectionstr[100];
-
- xsnprintf (sectionstr, sizeof sectionstr, "SPU/%s", annex);
-
- section = bfd_get_section_by_name (core_bfd, sectionstr);
- if (section == NULL)
- return TARGET_XFER_E_IO;
-
- size = bfd_section_size (core_bfd, section);
- if (offset >= size)
- return TARGET_XFER_EOF;
- size -= offset;
- if (size > len)
- size = len;
-
- if (size == 0)
- return TARGET_XFER_EOF;
- if (!bfd_get_section_contents (core_bfd, section, readbuf,
- (file_ptr) offset, size))
- {
- warning (_("Couldn't read SPU section in core file."));
- return TARGET_XFER_E_IO;
- }
-
- *xfered_len = (ULONGEST) size;
- return TARGET_XFER_OK;
- }
- else if (readbuf)
- {
- /* NULL annex requests list of all present spuids. */
- struct spuid_list list;
-
- list.buf = readbuf;
- list.offset = offset;
- list.len = len;
- list.pos = 0;
- list.written = 0;
- bfd_map_over_sections (core_bfd, add_to_spuid_list, &list);
-
- if (list.written == 0)
- return TARGET_XFER_EOF;
- else
- {
- *xfered_len = (ULONGEST) list.written;
- return TARGET_XFER_OK;
- }
- }
- return TARGET_XFER_E_IO;
-
case TARGET_OBJECT_SIGNAL_INFO:
if (readbuf)
{
return TARGET_XFER_E_IO;
default:
- return this->beneath->xfer_partial (object, annex, readbuf,
- writebuf, offset, len,
- xfered_len);
+ return this->beneath ()->xfer_partial (object, annex, readbuf,
+ writebuf, offset, len,
+ xfered_len);
}
}
const struct target_desc *
core_target::read_description ()
{
+ /* If the core file contains a target description note then we will use
+ that in preference to anything else. */
+ bfd_size_type tdesc_note_size = 0;
+ struct bfd_section *tdesc_note_section
+ = bfd_get_section_by_name (core_bfd, ".gdb-tdesc");
+ if (tdesc_note_section != nullptr)
+ tdesc_note_size = bfd_section_size (tdesc_note_section);
+ if (tdesc_note_size > 0)
+ {
+ gdb::char_vector contents (tdesc_note_size + 1);
+ if (bfd_get_section_contents (core_bfd, tdesc_note_section,
+ contents.data (), (file_ptr) 0,
+ tdesc_note_size))
+ {
+ /* Ensure we have a null terminator. */
+ contents[tdesc_note_size] = '\0';
+ const struct target_desc *result
+ = string_read_description_xml (contents.data ());
+ if (result != nullptr)
+ return result;
+ }
+ }
+
if (m_core_gdbarch && gdbarch_core_read_description_p (m_core_gdbarch))
{
const struct target_desc *result;
return result;
}
- return this->beneath->read_description ();
+ return this->beneath ()->read_description ();
}
-const char *
+std::string
core_target::pid_to_str (ptid_t ptid)
{
- static char buf[64];
struct inferior *inf;
int pid;
"process", with normal_pid_to_str. */
/* Try the LWPID field first. */
- pid = ptid_get_lwp (ptid);
+ pid = ptid.lwp ();
if (pid != 0)
- return normal_pid_to_str (pid_to_ptid (pid));
+ return normal_pid_to_str (ptid_t (pid));
/* Otherwise, this isn't a "threaded" core -- use the PID field, but
only if it isn't a fake PID. */
- inf = find_inferior_ptid (ptid);
+ inf = find_inferior_ptid (this, ptid);
if (inf != NULL && !inf->fake_pid_p)
return normal_pid_to_str (ptid);
/* No luck. We simply don't have a valid PID to print. */
- xsnprintf (buf, sizeof buf, "<main task>");
- return buf;
+ return "<main task>";
}
const char *
return true;
}
+/* Get a pointer to the current core target. If not connected to a
+ core target, return NULL. */
+
+static core_target *
+get_current_core_target ()
+{
+ target_ops *proc_target = current_inferior ()->process_target ();
+ return dynamic_cast<core_target *> (proc_target);
+}
+
+/* Display file backed mappings from core file. */
+
+void
+core_target::info_proc_mappings (struct gdbarch *gdbarch)
+{
+ if (!m_core_file_mappings.empty ())
+ {
+ printf_filtered (_("Mapped address spaces:\n\n"));
+ if (gdbarch_addr_bit (gdbarch) == 32)
+ {
+ printf_filtered ("\t%10s %10s %10s %10s %s\n",
+ "Start Addr",
+ " End Addr",
+ " Size", " Offset", "objfile");
+ }
+ else
+ {
+ printf_filtered (" %18s %18s %10s %10s %s\n",
+ "Start Addr",
+ " End Addr",
+ " Size", " Offset", "objfile");
+ }
+ }
+
+ for (const target_section &tsp : m_core_file_mappings)
+ {
+ ULONGEST start = tsp.addr;
+ ULONGEST end = tsp.endaddr;
+ ULONGEST file_ofs = tsp.the_bfd_section->filepos;
+ const char *filename = bfd_get_filename (tsp.the_bfd_section->owner);
+
+ if (gdbarch_addr_bit (gdbarch) == 32)
+ printf_filtered ("\t%10s %10s %10s %10s %s\n",
+ paddress (gdbarch, start),
+ paddress (gdbarch, end),
+ hex_string (end - start),
+ hex_string (file_ofs),
+ filename);
+ else
+ printf_filtered (" %18s %18s %10s %10s %s\n",
+ paddress (gdbarch, start),
+ paddress (gdbarch, end),
+ hex_string (end - start),
+ hex_string (file_ofs),
+ filename);
+ }
+}
+
+/* Implement "maintenance print core-file-backed-mappings" command.
+
+ If mappings are loaded, the results should be similar to the
+ mappings shown by "info proc mappings". This command is mainly a
+ debugging tool for GDB developers to make sure that the expected
+ mappings are present after loading a core file. For Linux, the
+ output provided by this command will be very similar (if not
+ identical) to that provided by "info proc mappings". This is not
+ necessarily the case for other OSes which might provide
+ more/different information in the "info proc mappings" output. */
+
+static void
+maintenance_print_core_file_backed_mappings (const char *args, int from_tty)
+{
+ core_target *targ = get_current_core_target ();
+ if (targ != nullptr)
+ targ->info_proc_mappings (targ->core_gdbarch ());
+}
+
+void _initialize_corelow ();
void
-_initialize_corelow (void)
+_initialize_corelow ()
{
add_target (core_target_info, core_target_open, filename_completer);
+ add_cmd ("core-file-backed-mappings", class_maintenance,
+ maintenance_print_core_file_backed_mappings,
+ _("Print core file's file-backed mappings."),
+ &maintenanceprintlist);
}