Add drutil_expand_rep_string to instrace_*.c samples #4138

CMakeLists.txt

# **********************************************************
# Copyright (c) 2010-2020 Google, Inc.    All rights reserved.
# Copyright (c) 2009-2010 VMware, Inc.    All rights reserved.
# **********************************************************

# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice,
#   this list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright notice,
#   this list of conditions and the following disclaimer in the documentation
#   and/or other materials provided with the distribution.
#
# * Neither the name of VMware, Inc. nor the names of its contributors may be
#   used to endorse or promote products derived from this software without
#   specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
# DAMAGE.

cmake_minimum_required(VERSION 3.7)

if ("${CMAKE_BUILD_TYPE}" MATCHES "Debug")
  set(DEBUG ON)
endif ("${CMAKE_BUILD_TYPE}" MATCHES "Debug")

# To match Makefiles and have just one build type per configured build
# dir, we collapse VS generator configs to a single choice.
# This must be done prior to the project() command and the var
# must be set in the cache.
if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
  if (DEBUG)
    set(CMAKE_CONFIGURATION_TYPES "Debug" CACHE STRING "" FORCE)
  else ()
    # Go w/ debug info (i#1392)
    set(CMAKE_CONFIGURATION_TYPES "RelWithDebInfo" CACHE STRING "" FORCE)
  endif ()
  # we want to use the <VAR>_<config> variants of config-dependent properties
  string(TOUPPER "${CMAKE_CONFIGURATION_TYPES}" upper)
  set(location_suffix "_${upper}")
else ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
  set(location_suffix "")
endif ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")

project(DynamoRIO_samples)

if ("${CMAKE_VERSION}" VERSION_EQUAL "3.9" OR
   "${CMAKE_VERSION}" VERSION_GREATER "3.9")
  # i#1375: We are ok w/ the new policy of SKIP_BUILD_RPATH not affecting install names.
  cmake_policy(SET CMP0068 NEW)
endif ()

set(output_dir "${PROJECT_BINARY_DIR}/bin")
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${output_dir}")
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_LIBRARY_OUTPUT_DIRECTORY}")
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${output_dir}")
if ("${CMAKE_GENERATOR}" MATCHES "Visual Studio")
  # we don't support the Debug and Release subdirs
  foreach (config ${CMAKE_CONFIGURATION_TYPES})
    string(TOUPPER "${config}" config_upper)
    set(CMAKE_RUNTIME_OUTPUT_DIRECTORY_${config_upper}
      "${CMAKE_RUNTIME_OUTPUT_DIRECTORY}")
    set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY_${config_upper}
      "${CMAKE_ARCHIVE_OUTPUT_DIRECTORY}")
    set(CMAKE_LIBRARY_OUTPUT_DIRECTORY_${config_upper}
      "${CMAKE_LIBRARY_OUTPUT_DIRECTORY}")
  endforeach ()
endif ()

if (BUILD_TESTS)
  # For automated sanity tests we can't have msgboxes or output
  set(SHOW_RESULTS_DEFAULT OFF)
else (BUILD_TESTS)
  set(SHOW_RESULTS_DEFAULT ON)
endif (BUILD_TESTS)

option(SHOW_RESULTS
  "Display client results in pop-up (Windows) or console message (Linux)"
  ${SHOW_RESULTS_DEFAULT})
if (SHOW_RESULTS)
  add_definitions(-DSHOW_RESULTS)
endif (SHOW_RESULTS)

option(SHOW_SYMBOLS "Use symbol lookup in clients that support it" ON)
if (SHOW_SYMBOLS)
  add_definitions(-DSHOW_SYMBOLS)
endif (SHOW_SYMBOLS)
if (NOT DEFINED GENERATE_PDBS)
  # support running tests over ssh where pdb building is problematic
  set(GENERATE_PDBS ON)
endif (NOT DEFINED GENERATE_PDBS)

# i#379: We usually want to build the samples with optimizations to improve the
# chances of inlining, but it's nice to be able to turn that off easily.  A
# release build should already have optimizations, so this should only really
# affect debug builds.
option(OPTIMIZE_SAMPLES
  "Build samples with optimizations to increase the chances of clean call inlining (overrides debug flags)"
  ON)
if (WIN32)
  set(OPT_CFLAGS "/O2")
else (WIN32)
  set(OPT_CFLAGS "-O2")
endif (WIN32)

if (DEBUG)
  set(OPT_CFLAGS "${OPT_CFLAGS} -DDEBUG")
endif (DEBUG)

# For C clients that only rely on the DR API and not on any 3rd party
# library routines, we could shrink the size of the client binary
# by disabling libc via "set(DynamoRIO_USE_LIBC OFF)".

if (NOT DEFINED DynamoRIO_DIR)
  set(DynamoRIO_DIR "${PROJECT_SOURCE_DIR}/../cmake" CACHE PATH
    "DynamoRIO installation's cmake directory")
endif (NOT DEFINED DynamoRIO_DIR)

find_package(DynamoRIO 8.0)
if (NOT DynamoRIO_FOUND)
  message(FATAL_ERROR "DynamoRIO package required to build")
endif(NOT DynamoRIO_FOUND)

if (WIN32)
  # disable stack protection: "unresolved external symbol ___security_cookie"
  # disable the warning "unreferenced formal parameter" #4100
  # disable the warning "conditional expression is constant" #4127
  # disable the warning "cast from function pointer to data pointer" #4054
  set(CL_CFLAGS "/GS- /wd4100 /wd4127 /wd4054")
  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${CL_CFLAGS}")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CL_CFLAGS}")
  add_definitions(-D_CRT_SECURE_NO_WARNINGS)
endif (WIN32)

if (OPTIMIZE_SAMPLES)
  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OPT_CFLAGS}")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OPT_CFLAGS}")
endif ()

function (add_sample_client name source_file_list extension_list)
  add_library(${name} SHARED ${source_file_list})
  configure_DynamoRIO_client(${name})
  foreach (ext ${extension_list})
    use_DynamoRIO_extension(${name} ${ext})
  endforeach (ext)

  # Provide a hint for how to use the client
  if (NOT DynamoRIO_INTERNAL OR NOT "${CMAKE_GENERATOR}" MATCHES "Ninja")
    DynamoRIO_get_full_path(path ${name} "${location_suffix}")
    add_custom_command(TARGET ${name}
      POST_BUILD
      COMMAND ${CMAKE_COMMAND}
      ARGS -E echo "Usage: pass to drconfig or drrun: -c ${path}"
      VERBATIM)
  endif ()


endfunction (add_sample_client)

function (add_sample_standalone name source_file_list)
  add_executable(${name} ${source_file_list})

  configure_DynamoRIO_standalone(${name})

  # Provide a hint for running
  if (NOT DynamoRIO_INTERNAL OR NOT "${CMAKE_GENERATOR}" MATCHES "Ninja")
    if (UNIX)
      set(FIND_MSG "(set LD_LIBRARY_PATH)")
    else (UNIX)
      set(FIND_MSG "(set PATH or copy to same directory)")
    endif (UNIX)
    add_custom_command(TARGET ${name}
      POST_BUILD
      COMMAND ${CMAKE_COMMAND}
      ARGS -E echo "Make sure the loader finds the dynamorio library ${FIND_MSG}"
      VERBATIM)
  endif ()
endfunction (add_sample_standalone)

###########################################################################

# As we'll be calling configure_DynamoRIO_{client,standalone} from within
# a function scope, we must set the global vars ahead of time:
configure_DynamoRIO_global(OFF ON)

# Use ;-separated lists for source files and extensions.

add_sample_client(bbbuf       "bbbuf.c"         "drmgr;drreg;drx")
add_sample_client(bbcount     "bbcount.c"       "drmgr;drreg;drx")
add_sample_client(bbsize      "bbsize.c"        "drmgr;drx")
add_sample_client(div         "div.c"           "drmgr")
add_sample_client(empty       "empty.c"         "")
add_sample_client(memtrace_simple "memtrace_simple.c;utils.c" "drmgr;drreg;drutil;drx")
add_sample_client(memval_simple   "memval_simple.c;utils.c"   "drmgr;drreg;drutil;drx")
add_sample_client(instrace_simple "instrace_simple.c;utils.c" "drmgr;drreg;drx")
add_sample_client(instrace_simple_expand_rep "instrace_simple_expand_rep.c;utils.c" "drmgr;drreg;drx;drutil")
add_sample_client(opcode_count    "opcode_count.cpp"    "drmgr;drreg;drx;droption")
if (X86) # FIXME i#1551, i#1569: port to ARM and AArch64
  add_sample_client(cbr         "cbr.c"           "drmgr")
  add_sample_client(countcalls  "countcalls.c"    "drmgr;drreg")
  add_sample_client(inc2add     "inc2add.c"       "drmgr;drreg")
  add_sample_client(memtrace_x86_binary "memtrace_x86.c;utils.c"
    "drcontainers;drmgr;drreg;drutil;drx")
  add_sample_client(memtrace_x86_text   "memtrace_x86.c;utils.c"
    "drcontainers;drmgr;drreg;drutil;drx")
  _DR_append_property_list(TARGET memtrace_x86_text COMPILE_DEFINITIONS "OUTPUT_TEXT")
  add_sample_client(instrace_x86_binary "instrace_x86.c;utils.c"
    "drcontainers;drmgr;drreg;drx")
  add_sample_client(instrace_x86_text   "instrace_x86.c;utils.c"
    "drcontainers;drmgr;drreg;drx")
  _DR_append_property_list(TARGET instrace_x86_text COMPILE_DEFINITIONS "OUTPUT_TEXT")
  add_sample_client(prefetch    "prefetch.c"      "drmgr")
  if (NOT WIN32)
    add_sample_client(ssljack     "ssljack.c"       "drmgr;drwrap")
  endif (NOT WIN32)
  # dr_insert_mbr_instrumentation is NYI
  add_sample_client(modxfer     "modxfer.c;utils.c"     "drmgr;drreg;drx")
  add_sample_client(modxfer_app2lib "modxfer_app2lib.c" "drmgr")
  add_sample_client(instrcalls  "instrcalls.c;utils.c"  "drmgr;drsyms;drx")
  # dr_insert_cbr_instrument_ex is NYI
  add_sample_client(cbrtrace    "cbrtrace.c;utils.c"    "drmgr;drx")
  add_sample_client(hot_bbcount "hot_bbcount.c"         "drmgr;drreg;drbbdup;drx")
endif (X86)
add_sample_client(wrap        "wrap.c"          "drmgr;drwrap")
add_sample_client(signal      "signal.c"        "drmgr")
add_sample_client(syscall     "syscall.c"       "drmgr")
add_sample_client(inline      "inline.c"        "drmgr;drcontainers")
add_sample_client(inscount    "inscount.cpp"    "drmgr;droption")
add_sample_client(opcodes     "opcodes.c"       "drmgr;drreg;drx")
add_sample_client(stl_test    "stl_test.cpp"    "")

# Customized code
add_sample_client(mywrap        "mywrap.c"          "drmgr;drwrap;drsyms")
add_sample_client(trace_target_func_usage "trace_target_func_usage.c;utils.c" "drmgr;drreg;drutil;drx;drwrap;drsyms")

if (WIN32)
  # This client is Windows-only.
  add_sample_client(stats     "stats.c;utils.c"         "drmgr;drreg;drx")

  # XXX i#893: drwrap's asm isn't SEH compliant.
  _DR_append_property_string(TARGET wrap LINK_FLAGS "/safeseh:no")
endif ()

add_sample_standalone(tracedump   "tracedump.c")

instrace_simple_expand_rep.c

/* ******************************************************************************
 * Copyright (c) 2011-2018 Google, Inc.  All rights reserved.
 * Copyright (c) 2010 Massachusetts Institute of Technology  All rights reserved.
 * ******************************************************************************/

/*
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * * Neither the name of VMware, Inc. nor the names of its contributors may be
 *   used to endorse or promote products derived from this software without
 *   specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

/* Code Manipulation API Sample:
 * instrace_simple.c
 *
 * Collects a dynamic instruction trace and dumps it to a text file.
 * This is a simpler (and slower) version of instrace_x86.c.
 *
 * (1) It fills a per-thread-buffer from inlined instrumentation.
 * (2) It calls a clean call to dump the buffer into a file.
 *
 * The trace is a simple text file with each line containing the PC and
 * the opcode of the instruction.
 *
 * This client is a simple implementation of an instruction tracing tool
 * without instrumentation optimization.  It also uses simple absolute PC
 * values and does not separate them into library offsets.
 * Additionally, dumping as text is much slower than dumping as
 * binary.  See instrace_x86.c for a higher-performance sample.
 */

#include <stdio.h>
#include <stddef.h> /* for offsetof */
#include "dr_api.h"
#include "drmgr.h"
#include "drreg.h"
#include "drutil.h"
#include "utils.h"

/* Each ins_ref_t describes an executed instruction. */
typedef struct _ins_ref_t {
    app_pc pc;
    int opcode;
} ins_ref_t;

/* Max number of ins_ref a buffer can have. It should be big enough
 * to hold all entries between clean calls.
 */
#define MAX_NUM_INS_REFS 8192
/* The maximum size of buffer for holding ins_refs. */
#define MEM_BUF_SIZE (sizeof(ins_ref_t) * MAX_NUM_INS_REFS)

/* thread private log file and counter */
typedef struct {
    byte *seg_base;
    ins_ref_t *buf_base;
    file_t log;
    FILE *logf;
    uint64 num_refs;
} per_thread_t;

static client_id_t client_id;
static void *mutex;     /* for multithread support */
static uint64 num_refs; /* keep a global instruction reference count */

/* Allocated TLS slot offsets */
enum {
    INSTRACE_TLS_OFFS_BUF_PTR,
    INSTRACE_TLS_COUNT, /* total number of TLS slots allocated */
};
static reg_id_t tls_seg;
static uint tls_offs;
static int tls_idx;
#define TLS_SLOT(tls_base, enum_val) (void **)((byte *)(tls_base) + tls_offs + (enum_val))
#define BUF_PTR(tls_base) *(ins_ref_t **)TLS_SLOT(tls_base, INSTRACE_TLS_OFFS_BUF_PTR)

#define MINSERT instrlist_meta_preinsert

static void
instrace(void *drcontext)
{
    per_thread_t *data;
    ins_ref_t *ins_ref, *buf_ptr;

    data = drmgr_get_tls_field(drcontext, tls_idx);
    buf_ptr = BUF_PTR(data->seg_base);
    /* Example of dumped file content:
     *   0x7f59c2d002d3: call
     *   0x7ffeacab0ec8: mov
     */
    /* We use libc's fprintf as it is buffered and much faster than dr_fprintf
     * for repeated printing that dominates performance, as the printing does here.
     */
    for (ins_ref = (ins_ref_t *)data->buf_base; ins_ref < buf_ptr; ins_ref++) {
        /* We use PIFX to avoid leading zeroes and shrink the resulting file. */
        fprintf(data->logf, PIFX ",%s\n", (ptr_uint_t)ins_ref->pc,
                decode_opcode_name(ins_ref->opcode));
        data->num_refs++;
    }
    BUF_PTR(data->seg_base) = data->buf_base;
}

/* clean_call dumps the memory reference info to the log file */
static void
clean_call(void)
{
    void *drcontext = dr_get_current_drcontext();
    instrace(drcontext);
}

static void
insert_load_buf_ptr(void *drcontext, instrlist_t *ilist, instr_t *where, reg_id_t reg_ptr)
{
    dr_insert_read_raw_tls(drcontext, ilist, where, tls_seg,
                           tls_offs + INSTRACE_TLS_OFFS_BUF_PTR, reg_ptr);
}

static void
insert_update_buf_ptr(void *drcontext, instrlist_t *ilist, instr_t *where,
                      reg_id_t reg_ptr, int adjust)
{
    MINSERT(
        ilist, where,
        XINST_CREATE_add(drcontext, opnd_create_reg(reg_ptr), OPND_CREATE_INT16(adjust)));
    dr_insert_write_raw_tls(drcontext, ilist, where, tls_seg,
                            tls_offs + INSTRACE_TLS_OFFS_BUF_PTR, reg_ptr);
}

static void
insert_save_opcode(void *drcontext, instrlist_t *ilist, instr_t *where, reg_id_t base,
                   reg_id_t scratch, int opcode)
{
    scratch = reg_resize_to_opsz(scratch, OPSZ_2);
    MINSERT(ilist, where,
            XINST_CREATE_load_int(drcontext, opnd_create_reg(scratch),
                                  OPND_CREATE_INT16(opcode)));
    MINSERT(ilist, where,
            XINST_CREATE_store_2bytes(
                drcontext, OPND_CREATE_MEM16(base, offsetof(ins_ref_t, opcode)),
                opnd_create_reg(scratch)));
}

static void
insert_save_pc(void *drcontext, instrlist_t *ilist, instr_t *where, reg_id_t base,
               reg_id_t scratch, app_pc pc)
{
    instrlist_insert_mov_immed_ptrsz(drcontext, (ptr_int_t)pc, opnd_create_reg(scratch),
                                     ilist, where, NULL, NULL);
    MINSERT(ilist, where,
            XINST_CREATE_store(drcontext,
                               OPND_CREATE_MEMPTR(base, offsetof(ins_ref_t, pc)),
                               opnd_create_reg(scratch)));
}

/* insert inline code to add an instruction entry into the buffer */
static void
instrument_instr(void *drcontext, instrlist_t *ilist, instr_t *where)
{
    /* We need two scratch registers */
    reg_id_t reg_ptr, reg_tmp;
    if (drreg_reserve_register(drcontext, ilist, where, NULL, &reg_ptr) !=
            DRREG_SUCCESS ||
        drreg_reserve_register(drcontext, ilist, where, NULL, &reg_tmp) !=
            DRREG_SUCCESS) {
        DR_ASSERT(false); /* cannot recover */
        return;
    }

    insert_load_buf_ptr(drcontext, ilist, where, reg_ptr);
    insert_save_pc(drcontext, ilist, where, reg_ptr, reg_tmp, instr_get_app_pc(where));
    insert_save_opcode(drcontext, ilist, where, reg_ptr, reg_tmp,
                       instr_get_opcode(where));
    insert_update_buf_ptr(drcontext, ilist, where, reg_ptr, sizeof(ins_ref_t));

    /* Restore scratch registers */
    if (drreg_unreserve_register(drcontext, ilist, where, reg_ptr) != DRREG_SUCCESS ||
        drreg_unreserve_register(drcontext, ilist, where, reg_tmp) != DRREG_SUCCESS)
        DR_ASSERT(false);
}

/* For each app instr, we insert inline code to fill the buffer. */
static dr_emit_flags_t
event_app_instruction(void *drcontext, void *tag, instrlist_t *bb, instr_t *instr,
                      bool for_trace, bool translating, void *user_data)
{
    /* we don't want to auto-predicate any instrumentation */
    drmgr_disable_auto_predication(drcontext, bb);

    if (!instr_is_app(instr))
        return DR_EMIT_DEFAULT;

    /* insert code to add an entry to the buffer */
    instrument_instr(drcontext, bb, instr);

    /* insert code once per bb to call clean_call for processing the buffer */
    if (drmgr_is_first_instr(drcontext, instr)
        /* XXX i#1698: there are constraints for code between ldrex/strex pairs,
         * so we minimize the instrumentation in between by skipping the clean call.
         * We're relying a bit on the typical code sequence with either ldrex..strex
         * in the same bb, in which case our call at the start of the bb is fine,
         * or with a branch in between and the strex at the start of the next bb.
         * However, there is still a chance that the instrumentation code may clear the
         * exclusive monitor state.
         * Using a fault to handle a full buffer should be more robust, and the
         * forthcoming buffer filling API (i#513) will provide that.
         */
        IF_AARCHXX(&&!instr_is_exclusive_store(instr)))
        dr_insert_clean_call(drcontext, bb, instr, (void *)clean_call, false, 0);

    return DR_EMIT_DEFAULT;
}

static void
event_thread_init(void *drcontext)
{
    per_thread_t *data = dr_thread_alloc(drcontext, sizeof(per_thread_t));
    DR_ASSERT(data != NULL);
    drmgr_set_tls_field(drcontext, tls_idx, data);

    /* Keep seg_base in a per-thread data structure so we can get the TLS
     * slot and find where the pointer points to in the buffer.
     */
    data->seg_base = dr_get_dr_segment_base(tls_seg);
    data->buf_base =
        dr_raw_mem_alloc(MEM_BUF_SIZE, DR_MEMPROT_READ | DR_MEMPROT_WRITE, NULL);
    DR_ASSERT(data->seg_base != NULL && data->buf_base != NULL);
    /* put buf_base to TLS as starting buf_ptr */
    BUF_PTR(data->seg_base) = data->buf_base;

    data->num_refs = 0;

    /* We're going to dump our data to a per-thread file.
     * On Windows we need an absolute path so we place it in
     * the same directory as our library. We could also pass
     * in a path as a client argument.
     */
    data->log =
        log_file_open(client_id, drcontext, NULL /* using client lib path */, "instrace",
#ifndef WINDOWS
                      DR_FILE_CLOSE_ON_FORK |
#endif
                          DR_FILE_ALLOW_LARGE);
    data->logf = log_stream_from_file(data->log);
    fprintf(data->logf, "Format: <instr address>,<opcode>\n");
}

static void
event_thread_exit(void *drcontext)
{
    per_thread_t *data;
    instrace(drcontext); /* dump any remaining buffer entries */
    data = drmgr_get_tls_field(drcontext, tls_idx);
    dr_mutex_lock(mutex);
    num_refs += data->num_refs;
    dr_mutex_unlock(mutex);
    log_stream_close(data->logf); /* closes fd too */
    dr_raw_mem_free(data->buf_base, MEM_BUF_SIZE);
    dr_thread_free(drcontext, data, sizeof(per_thread_t));
}

static dr_emit_flags_t
event_bb_app2app(void *drcontext, void *tag, instrlist_t *bb, bool for_trace,
                 bool translating)
{
    if (!drutil_expand_rep_string(drcontext, bb)) {
        DR_ASSERT(false);
        /* in release build, carry on: we'll just miss per-iter refs */
    }
    return DR_EMIT_DEFAULT;
}

static void
event_exit(void)
{
    dr_log(NULL, DR_LOG_ALL, 1, "Client 'instrace' num refs seen: " SZFMT "\n", num_refs);
    if (!dr_raw_tls_cfree(tls_offs, INSTRACE_TLS_COUNT))
        DR_ASSERT(false);

    if (!drmgr_unregister_tls_field(tls_idx) ||
        !drmgr_unregister_bb_app2app_event(event_bb_app2app) ||
        !drmgr_unregister_thread_init_event(event_thread_init) ||
        !drmgr_unregister_thread_exit_event(event_thread_exit) ||
        !drmgr_unregister_bb_insertion_event(event_app_instruction) ||
        drreg_exit() != DRREG_SUCCESS)
        DR_ASSERT(false);

    dr_mutex_destroy(mutex);
    drmgr_exit();
    drutil_exit();
}

DR_EXPORT void
dr_client_main(client_id_t id, int argc, const char *argv[])
{
    /* We need 2 reg slots beyond drreg's eflags slots => 3 slots */
    drreg_options_t ops = { sizeof(ops), 3, false };
    dr_set_client_name("DynamoRIO Sample Client 'instrace'",
                       "http://dynamorio.org/issues");
    if (!drmgr_init() || drreg_init(&ops) != DRREG_SUCCESS || !drutil_init())
        DR_ASSERT(false);

    /* register events */
    dr_register_exit_event(event_exit);
    if (!drmgr_register_thread_init_event(event_thread_init) ||
        !drmgr_register_bb_app2app_event(event_bb_app2app, NULL) ||
        !drmgr_register_thread_exit_event(event_thread_exit) ||
        !drmgr_register_bb_instrumentation_event(NULL /*analysis_func*/,
                                                 event_app_instruction, NULL))
        DR_ASSERT(false);

    client_id = id;
    mutex = dr_mutex_create();

    tls_idx = drmgr_register_tls_field();
    DR_ASSERT(tls_idx != -1);
    /* The TLS field provided by DR cannot be directly accessed from the code cache.
     * For better performance, we allocate raw TLS so that we can directly
     * access and update it with a single instruction.
     */
    if (!dr_raw_tls_calloc(&tls_seg, &tls_offs, INSTRACE_TLS_COUNT, 0))
        DR_ASSERT(false);

    dr_log(NULL, DR_LOG_ALL, 1, "Client 'instrace' initializing\n");
}