Alexandra Petlanova Hajkova 0432ce486d vgdb: implement the extended-remote protocol
Executing vgdb --multi makes vgdb talk the gdb extended-remote
protocol. This means that the gdb run command is supported and
vgdb will start up the program under valgrind. Which means you
don't need to run gdb and valgrind from different terminals.
Also vgdb keeps being connected to gdb after valgrind exits. So
you can easily rerun the program with the same breakpoints in
place.

vgdb now implements a minimal gdbserver that just recognizes
a few extended-remote protocol packets. Once it starts up valgrind
it sets up noack and qsupported then it will forward packets
between gdb and valgrind gdbserver. After valgrind shutsdown it
resumes handling gdb packets itself.

https://bugs.kde.org/show_bug.cgi?id=434057

Co-authored-by: Mark Wielaard <mark@klomp.org>
2023-04-14 00:08:53 +02:00

508 lines
17 KiB
C

/*--------------------------------------------------------------------*/
/*--- Command line options. m_options.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Valgrind, a dynamic binary instrumentation
framework.
Copyright (C) 2000-2017 Nicholas Nethercote
njn@valgrind.org
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>.
The GNU General Public License is contained in the file COPYING.
*/
#include "pub_core_basics.h"
#include "pub_core_vki.h"
#include "pub_core_options.h"
#include "pub_core_libcassert.h"
#include "pub_core_libcbase.h"
#include "pub_core_libcfile.h"
#include "pub_core_libcprint.h"
#include "pub_core_libcproc.h"
#include "pub_core_mallocfree.h"
#include "pub_core_seqmatch.h" // VG_(string_match)
#include "pub_core_aspacemgr.h"
// See pub_{core,tool}_options.h for explanations of all these.
static Clo_Mode clo_mode = cloE;
static Bool clo_recognised = False;
void VG_(set_Clo_Mode) (Clo_Mode mode)
{
clo_mode = mode;
clo_recognised = False;
}
Clo_Mode VG_(Clo_Mode) (void)
{
return clo_mode;
}
void VG_(set_Clo_Recognised) (void)
{
clo_recognised = True;
}
Bool VG_(Clo_Recognised) (void)
{
return clo_recognised;
}
Bool VG_(check_clom) (Clo_Mode modes, const HChar* arg, const HChar* option,
Bool recognised)
{
Bool res = recognised && (modes & VG_(Clo_Mode)());
Bool dynamic = cloD == VG_(Clo_Mode)();
if (recognised) {
VG_(set_Clo_Recognised) ();
if (dynamic && !res)
VG_(umsg)("Cannot change %s option dynamically\n", option);
else if (dynamic && VG_(clo_verbosity) >= 1)
VG_(umsg)("Handling new value %s for option %s\n", arg, option);
}
if (cloH == VG_(Clo_Mode)() && (cloD & modes))
VG_(list_clo)(option);
return res;
}
/* Define, and set defaults. */
const HChar *VG_(clo_toolname) = "memcheck"; // default to Memcheck
VexControl VG_(clo_vex_control);
VexRegisterUpdates VG_(clo_px_file_backed) = VexRegUpd_INVALID;
Bool VG_(clo_error_limit) = True;
Int VG_(clo_error_exitcode) = 0;
HChar *VG_(clo_error_markers)[2] = {NULL, NULL};
Bool VG_(clo_exit_on_first_error) = False;
Bool VG_(clo_show_error_list) = False;
#if defined(VGPV_arm_linux_android) \
|| defined(VGPV_x86_linux_android) \
|| defined(VGPV_mips32_linux_android) \
|| defined(VGPV_arm64_linux_android) \
|| defined(VGP_nanomips_linux)
VgVgdb VG_(clo_vgdb) = Vg_VgdbNo; // currently disabled on Android
#else
VgVgdb VG_(clo_vgdb) = Vg_VgdbYes;
#endif
Int VG_(clo_vgdb_poll) = 5000;
Int VG_(clo_vgdb_error) = 999999999;
Bool VG_(clo_launched_with_multi) = False;
UInt VG_(clo_vgdb_stop_at) = 0;
const HChar *VG_(clo_vgdb_prefix) = NULL;
const HChar *VG_(arg_vgdb_prefix) = NULL;
Bool VG_(clo_vgdb_shadow_registers) = False;
Int VG_(clo_gen_suppressions) = 0;
Int VG_(clo_sanity_level) = 1;
Int VG_(clo_verbosity) = 1;
Bool VG_(clo_stats) = False;
Bool VG_(clo_xml) = False;
const HChar* VG_(clo_xml_user_comment) = NULL;
Bool VG_(clo_demangle) = True;
const HChar* VG_(clo_soname_synonyms) = NULL;
Bool VG_(clo_trace_children) = False;
const HChar* VG_(clo_trace_children_skip) = NULL;
const HChar* VG_(clo_trace_children_skip_by_arg) = NULL;
Bool VG_(clo_child_silent_after_fork) = False;
const HChar *VG_(clo_log_fname_unexpanded) = NULL;
const HChar *VG_(clo_xml_fname_unexpanded) = NULL;
Bool VG_(clo_time_stamp) = False;
Int VG_(clo_input_fd) = 0; /* stdin */
Bool VG_(clo_default_supp) = True;
XArray *VG_(clo_suppressions); // array of strings
XArray *VG_(clo_fullpath_after); // array of strings
const HChar* VG_(clo_extra_debuginfo_path) = NULL;
const HChar* VG_(clo_debuginfo_server) = NULL;
Bool VG_(clo_allow_mismatched_debuginfo) = False;
UChar VG_(clo_trace_flags) = 0; // 00000000b
Bool VG_(clo_profyle_sbs) = False;
UChar VG_(clo_profyle_flags) = 0; // 00000000b
ULong VG_(clo_profyle_interval) = 0;
Int VG_(clo_trace_notbelow) = -1; // unspecified
Int VG_(clo_trace_notabove) = -1; // unspecified
Bool VG_(clo_trace_syscalls) = False;
Bool VG_(clo_trace_signals) = False;
Bool VG_(clo_trace_symtab) = False;
const HChar* VG_(clo_trace_symtab_patt) = "*";
Bool VG_(clo_trace_cfi) = False;
Bool VG_(clo_debug_dump_syms) = False;
Bool VG_(clo_debug_dump_line) = False;
Bool VG_(clo_debug_dump_frames) = False;
Bool VG_(clo_trace_redir) = False;
enum FairSchedType
VG_(clo_fair_sched) = disable_fair_sched;
/* VG_(clo_scheduling_quantum) defines the thread-scheduling timeslice,
in terms of the number of basic blocks we attempt to run each thread for.
Smaller values give finer interleaving but much increased scheduling
overheads. */
Word VG_(clo_scheduling_quantum) = 100000;
Bool VG_(clo_trace_sched) = False;
Bool VG_(clo_profile_heap) = False;
UInt VG_(clo_progress_interval) = 0; /* in seconds, 1 .. 3600,
or 0 == disabled */
Int VG_(clo_core_redzone_size) = CORE_REDZONE_DEFAULT_SZB;
// A value != -1 overrides the tool-specific value
// VG_(needs_malloc_replacement).tool_client_redzone_szB
Int VG_(clo_redzone_size) = -1;
VgXTMemory VG_(clo_xtree_memory) = Vg_XTMemory_None;
const HChar* VG_(clo_xtree_memory_file) = "xtmemory.kcg.%p";
Bool VG_(clo_xtree_compress_strings) = True;
#if defined(VGO_linux)
Bool VG_(clo_enable_debuginfod) = True;
#endif
Int VG_(clo_dump_error) = 0;
Int VG_(clo_backtrace_size) = 12;
Int VG_(clo_merge_recursive_frames) = 0; // default value: no merge
UInt VG_(clo_sim_hints) = 0;
Bool VG_(clo_sym_offsets) = False;
Bool VG_(clo_read_inline_info) = False; // Or should be put it to True by default ???
Bool VG_(clo_read_var_info) = False;
XArray *VG_(clo_req_tsyms); // array of strings
Bool VG_(clo_run_libc_freeres) = True;
Bool VG_(clo_run_cxx_freeres) = True;
UInt VG_(clo_track_fds) = 0;
Bool VG_(clo_show_below_main)= False;
Bool VG_(clo_keep_debuginfo) = False;
Bool VG_(clo_show_emwarns) = False;
Word VG_(clo_max_stackframe) = 2000000;
UInt VG_(clo_max_threads) = MAX_THREADS_DEFAULT;
Word VG_(clo_main_stacksize) = 0; /* use client's rlimit.stack */
Word VG_(clo_valgrind_stacksize) = VG_DEFAULT_STACK_ACTIVE_SZB;
Bool VG_(clo_wait_for_gdb) = False;
UInt VG_(clo_kernel_variant) = 0;
Bool VG_(clo_dsymutil) = True;
Bool VG_(clo_sigill_diag) = True;
UInt VG_(clo_unw_stack_scan_thresh) = 0; /* disabled by default */
UInt VG_(clo_unw_stack_scan_frames) = 5;
// Set clo_smc_check so that it provides transparent self modifying
// code support for "correct" programs at the smallest achievable
// expense for this arch.
#if defined(VGA_x86) || defined(VGA_amd64) || defined(VGA_s390x)
VgSmc VG_(clo_smc_check) = Vg_SmcAllNonFile;
#elif defined(VGA_ppc32) || defined(VGA_ppc64be) || defined(VGA_ppc64le) \
|| defined(VGA_arm) || defined(VGA_arm64) \
|| defined(VGA_mips32) || defined(VGA_mips64) || defined(VGA_nanomips)
VgSmc VG_(clo_smc_check) = Vg_SmcStack;
#else
# error "Unknown arch"
#endif
#if defined(VGO_darwin)
UInt VG_(clo_resync_filter) = 1; /* enabled, but quiet */
#else
UInt VG_(clo_resync_filter) = 0; /* disabled */
#endif
/*====================================================================*/
/*=== File expansion ===*/
/*====================================================================*/
// Copies the string, prepending it with the startup working directory, and
// expanding %p and %q entries. Returns a new, malloc'd string.
HChar* VG_(expand_file_name)(const HChar* option_name, const HChar* format)
{
const HChar *base_dir;
Int len, i = 0, j = 0;
HChar* out;
const HChar *message = NULL;
base_dir = VG_(get_startup_wd)();
if (VG_STREQ(format, "")) {
// Empty name, bad.
message = "No filename given\n";
goto bad;
}
// If 'format' starts with a '~', abort -- the user probably expected the
// shell to expand but it didn't (see bug 195268 for details). This means
// that we don't allow a legitimate filename beginning with '~' but that
// seems very unlikely.
if (format[0] == '~') {
message =
"Filename begins with '~'\n"
"You probably expected the shell to expand the '~', but it\n"
"didn't. The rules for '~'-expansion vary from shell to shell.\n"
"You might have more luck using $HOME instead.\n";
goto bad;
}
len = VG_(strlen)(format) + 1;
out = VG_(malloc)( "options.efn.1", len );
#define ENSURE_THIS_MUCH_SPACE(x) \
if (j + x >= len) { \
len += (10 + x); \
out = VG_(realloc)("options.efn.2(multiple)", out, len); \
}
while (format[i]) {
if (format[i] != '%') {
ENSURE_THIS_MUCH_SPACE(1);
out[j++] = format[i++];
} else {
// We saw a '%'. What's next...
i++;
if ('%' == format[i]) {
// Replace '%%' with '%'.
ENSURE_THIS_MUCH_SPACE(1);
out[j++] = format[i++];
}
else if ('p' == format[i]) {
// Print the PID. Assume that it's not longer than 10 chars --
// reasonable since 'pid' is an Int (ie. 32 bits).
Int pid = VG_(getpid)();
ENSURE_THIS_MUCH_SPACE(10);
j += VG_(sprintf)(&out[j], "%d", pid);
i++;
}
else if ('n' == format[i]) {
// Print a seq nr.
static Int last_pid;
static Int seq_nr;
Int pid = VG_(getpid)();
if (last_pid != pid)
seq_nr = 0;
last_pid = pid;
seq_nr++;
ENSURE_THIS_MUCH_SPACE(10);
j += VG_(sprintf)(&out[j], "%d", seq_nr);
i++;
}
else if ('q' == format[i]) {
i++;
if ('{' == format[i]) {
// Get the env var name, print its contents.
HChar *qual;
Int begin_qualname = ++i;
while (True) {
if (0 == format[i]) {
message = "Missing '}' in %q specifier\n";
goto bad;
} else if ('}' == format[i]) {
Int qualname_len = i - begin_qualname;
HChar qualname[qualname_len + 1];
VG_(strncpy)(qualname, format + begin_qualname,
qualname_len);
qualname[qualname_len] = '\0';
qual = VG_(getenv)(qualname);
if (NULL == qual) {
// This memory will leak, But we don't care because
// VG_(fmsg_bad_option) will terminate the process.
HChar *str = VG_(malloc)("options.efn.3",
100 + qualname_len);
VG_(sprintf)(str,
"Environment variable '%s' is not set\n",
qualname);
message = str;
goto bad;
}
i++;
break;
}
i++;
}
ENSURE_THIS_MUCH_SPACE(VG_(strlen)(qual));
j += VG_(sprintf)(&out[j], "%s", qual);
} else {
message = "Expected '{' after '%q'\n";
goto bad;
}
}
else {
// Something else, abort.
message = "Expected 'p' or 'q' or '%' after '%'\n";
goto bad;
}
}
}
ENSURE_THIS_MUCH_SPACE(1);
out[j++] = 0;
// If 'out' is not an absolute path name, prefix it with the startup dir.
if (out[0] != '/') {
if (base_dir == NULL) {
message = "Current working dir doesn't exist, use absolute path\n";
goto bad;
}
len = VG_(strlen)(base_dir) + 1 + VG_(strlen)(out) + 1;
HChar *absout = VG_(malloc)("options.efn.4", len);
VG_(strcpy)(absout, base_dir);
VG_(strcat)(absout, "/");
VG_(strcat)(absout, out);
VG_(free)(out);
out = absout;
}
return out;
bad: {
vg_assert(message != NULL);
// 2: 1 for the '=', 1 for the NUL.
HChar opt[VG_(strlen)(option_name) + VG_(strlen)(format) + 2];
VG_(sprintf)(opt, "%s=%s", option_name, format);
VG_(fmsg_bad_option)(opt, "%s", message);
VG_(exit)(1); // Cannot continue
/*NOTREACHED*/
}
}
static int col = 0;
void VG_(list_clo)(const HChar *qq_option)
{
int len = VG_(strlen)(qq_option);
if (col + len + 1 > 80) {
VG_(printf)("\n");
col = 0;
}
if (col == 0) {
VG_(printf)(" ");
col += 4;
} else {
VG_(printf)(" ");
col += 1;
}
VG_(printf)("%s", qq_option);
col += len;
}
void VG_(list_dynamic_options) (void)
{
HChar dummy[40];
VG_(sprintf)(dummy, "%s", "<dummy option to trigger help>");
VG_(printf)(" dynamically changeable options:\n");
VG_(process_dynamic_option) (cloH, dummy);
if (col > 0) {
VG_(printf)("\n");
col = 0;
}
}
/*====================================================================*/
/*=== --trace-children= support ===*/
/*====================================================================*/
static HChar const* consume_commas ( HChar const* c ) {
while (*c && *c == ',') {
++c;
}
return c;
}
static HChar const* consume_field ( HChar const* c ) {
while (*c && *c != ',') {
++c;
}
return c;
}
/* Should we trace into this child executable (across execve, spawn etc) ?
This involves considering --trace-children=,
--trace-children-skip=, --trace-children-skip-by-arg=, and the name
of the executable. 'child_argv' must not include the name of the
executable itself; iow child_argv[0] must be the first arg, if any,
for the child. */
Bool VG_(should_we_trace_this_child) ( const HChar* child_exe_name,
const HChar** child_argv )
{
// child_exe_name is pulled out of the guest's space. We
// should be at least marginally cautious with it, lest it
// explode or burst into flames unexpectedly.
if (child_exe_name == NULL || VG_(strlen)(child_exe_name) == 0)
return VG_(clo_trace_children); // we know narfink
// If --trace-children=no, the answer is simply NO.
if (! VG_(clo_trace_children))
return False;
// Otherwise, look for other reasons to say NO. First,
// see if the exe name matches any of the patterns specified
// by --trace-children-skip=.
if (VG_(clo_trace_children_skip)) {
HChar const* last = VG_(clo_trace_children_skip);
HChar const* name = child_exe_name;
while (*last) {
Bool matches;
HChar* patt;
HChar const* first = consume_commas(last);
last = consume_field(first);
if (first == last)
break;
vg_assert(last > first);
/* copy the candidate string into a temporary malloc'd block
so we can use VG_(string_match) on it. */
patt = VG_(calloc)("m_options.swttc.1", last - first + 1, 1);
VG_(memcpy)(patt, first, last - first);
vg_assert(patt[last-first] == 0);
matches = VG_(string_match)(patt, name);
VG_(free)(patt);
if (matches)
return False;
}
}
// Check if any of the args match any of the patterns specified
// by --trace-children-skip-by-arg=.
if (VG_(clo_trace_children_skip_by_arg) && child_argv != NULL) {
HChar const* last = VG_(clo_trace_children_skip_by_arg);
while (*last) {
Int i;
Bool matches;
HChar* patt;
HChar const* first = consume_commas(last);
last = consume_field(first);
if (first == last)
break;
vg_assert(last > first);
/* copy the candidate string into a temporary malloc'd block
so we can use VG_(string_match) on it. */
patt = VG_(calloc)("m_options.swttc.1", last - first + 1, 1);
VG_(memcpy)(patt, first, last - first);
vg_assert(patt[last-first] == 0);
for (i = 0; child_argv[i]; i++) {
matches = VG_(string_match)(patt, child_argv[i]);
if (matches) {
VG_(free)(patt);
return False;
}
}
VG_(free)(patt);
}
}
// --trace-children=yes, and this particular executable isn't
// excluded
return True;
}
/*--------------------------------------------------------------------*/
/*--- end ---*/
/*--------------------------------------------------------------------*/