extern void __stack_logging_fork_prepare();
extern void __stack_logging_fork_parent();
extern void __stack_logging_fork_child();
+extern void __stack_logging_early_finished();
// support for gdb and others checking for stack_logging locks
__private_extern__ boolean_t __stack_logging_locked();
static const char *stack_log_file_suffix = ".index";
static const char *stack_log_link_suffix = ".link";
-static char stack_log_location[PATH_MAX];
-static char stack_log_reference_file[PATH_MAX];
-static char index_file_path[PATH_MAX];
+static void *stack_log_path_buffers = NULL;
+static char *stack_log_location = NULL;
+static char *stack_log_reference_file = NULL;
+char *__stack_log_file_path__ = NULL;
static int index_file_descriptor = -1;
// for accessing remote log files
return uniquing_table;
}
+static void
+__destroy_uniquing_table(backtrace_uniquing_table* table)
+{
+ deallocate_pages(table->table, table->tableSize);
+ deallocate_pages(table, sizeof(backtrace_uniquing_table));
+}
+
static void
__expand_uniquing_table(backtrace_uniquing_table *uniquing_table)
{
static int
__enter_frames_in_table(backtrace_uniquing_table *uniquing_table, uint64_t *foundIndex, mach_vm_address_t *frames, int32_t count)
{
+ // The hash values need to be the same size as the addresses (because we use the value -1), for clarity, define a new type
+ typedef mach_vm_address_t hash_index_t;
+
mach_vm_address_t thisPC;
- uint64_t hash, uParent = (uint64_t)(-1ll), modulus = (uniquing_table->numNodes-uniquing_table->untouchableNodes-1);
+ hash_index_t hash, uParent = (hash_index_t)(-1ll), modulus = (uniquing_table->numNodes-uniquing_table->untouchableNodes-1);
int32_t collisions, lcopy = count, returnVal = 1;
- uint64_t hash_multiplier = ((uniquing_table->numNodes - uniquing_table->untouchableNodes)/(uniquing_table->max_collide*2+1));
+ hash_index_t hash_multiplier = ((uniquing_table->numNodes - uniquing_table->untouchableNodes)/(uniquing_table->max_collide*2+1));
mach_vm_address_t *node;
while (--lcopy >= 0) {
thisPC = frames[lcopy];
}
}
-// If successful, returns path to log file that was created. Otherwise returns NULL.
+/*
+ * <rdar://problem/11128080> if we needed to call confstr during init then setting this
+ * flag will postpone stack logging until after Libsystem's initialiser has run.
+ */
+static void
+postpone_stack_logging(void)
+{
+ _malloc_printf(ASL_LEVEL_INFO, "stack logging postponed until after initialization.\n");
+ stack_logging_postponed = 1;
+}
+
+/*
+ * Check various temporary directory options starting with _PATH_TMP and use confstr.
+ * Allocating and releasing target buffer is the caller's responsibility.
+ */
+static bool
+get_writeable_temp_dir(char* target)
+{
+ if (!target) return false;
+ if (-1 != access(_PATH_TMP, W_OK)) {
+ strlcpy(target, _PATH_TMP, (size_t)PATH_MAX);
+ return true;
+ }
+ if (getenv("TMPDIR") && (-1 != access(getenv("TMPDIR"), W_OK))) {
+ strlcpy(target, getenv("TMPDIR"), (size_t)PATH_MAX);
+ return true;
+ }
+ if (stack_logging_finished_init) {
+ size_t n = confstr(_CS_DARWIN_USER_TEMP_DIR, target, (size_t) PATH_MAX);
+ if ((n > 0) && (n < PATH_MAX)) return true;
+ n = confstr(_CS_DARWIN_USER_CACHE_DIR, target, (size_t) PATH_MAX);
+ if ((n > 0) && (n < PATH_MAX)) return true;
+ } else {
+ /* <rdar://problem/11128080> Can't call confstr during init, so postpone
+ logging till after */
+ postpone_stack_logging();
+ }
+ /* No writeable tmp directory found. Maybe shd try /private/var/tmp for device here ... */
+ *target = '\0';
+ return false;
+}
+
+/*
+ * If successful, returns path to log file that was created, otherwise NULL.
+ *
+ * The log could be in one of 3 places (in decreasing order of preference)
+ *
+ * 1) value of environment variable MallocStackLoggingDirectory
+ * 2) the temp directory /tmp for desktop apps and internal apps on devices, or
+ * 3) the sandbox location + tmp/ in case of 3rd party apps on the device.
+ *
+ * For 1 and 3, we create a .link file with the path of the file. We prefer to
+ * create this file in /tmp, but if we are unable to (device 3rd party case),
+ * we create it in the same location as the .index file and issue a message
+ * in syslog asking for it to be copied to /tmp to enable tools.
+ *
+ */
static char *
create_log_file(void)
{
const char *progname = getprogname();
char *created_log_location = NULL;
+ if (stack_log_path_buffers == NULL) {
+ /*
+ * on first use, allocate buffers directly from the OS without
+ * using malloc
+ */
+
+ stack_log_path_buffers = allocate_pages((uint64_t)round_page(3*PATH_MAX));
+ if (stack_log_path_buffers == NULL) {
+ _malloc_printf(ASL_LEVEL_INFO, "unable to allocate memory for path buffers\n");
+ return NULL;
+ }
+
+ stack_log_location = &((char *)stack_log_path_buffers)[0*PATH_MAX];
+ stack_log_reference_file = &((char *)stack_log_path_buffers)[1*PATH_MAX];
+ __stack_log_file_path__ = &((char *)stack_log_path_buffers)[2*PATH_MAX];
+ }
+
// WARNING! use of snprintf can induce malloc() calls
bool use_alternate_location = false;
char *evn_log_directory = getenv("MallocStackLoggingDirectory");
+ size_t stack_log_len;
if (evn_log_directory && *evn_log_directory) {
use_alternate_location = true;
strlcpy(stack_log_location, evn_log_directory, (size_t)PATH_MAX);
- size_t evn_log_len = strlen(stack_log_location);
- // add the '/' only if it's not already there.
- if (evn_log_directory[evn_log_len-1] != '/') {
- strlcat(stack_log_location, "/", (size_t)PATH_MAX);
+ }
+ if (!use_alternate_location || (access(stack_log_location, W_OK) == -1)) {
+ if (!get_writeable_temp_dir(stack_log_location)) {
+ if (!stack_logging_postponed) {
+ _malloc_printf(ASL_LEVEL_INFO, "No writeable tmp dir\n");
+ }
+ return NULL;
}
- } else {
- strlcpy(stack_log_location, _PATH_TMP, (size_t)PATH_MAX);
+ if (0 != strcmp(stack_log_location, _PATH_TMP))
+ use_alternate_location = true;
+ }
+ stack_log_len = strlen(stack_log_location);
+ // add the '/' only if it's not already there.
+ if (stack_log_location[stack_log_len-1] != '/') {
+ strlcat(stack_log_location, "/", (size_t)PATH_MAX);
+ ++stack_log_len;
}
- strlcat(stack_log_location, stack_log_file_base_name, (size_t)PATH_MAX);
- append_int(stack_log_location, pid, (size_t)PATH_MAX);
+ strlcpy(__stack_log_file_path__, stack_log_location, (size_t)PATH_MAX);
+
+ strlcat(__stack_log_file_path__, stack_log_file_base_name, (size_t)PATH_MAX);
+ append_int(__stack_log_file_path__, pid, (size_t)PATH_MAX);
if (progname && progname[0] != '\0') {
- strlcat(stack_log_location, ".", (size_t)PATH_MAX);
- strlcat(stack_log_location, progname, (size_t)PATH_MAX);
+ strlcat(__stack_log_file_path__, ".", (size_t)PATH_MAX);
+ strlcat(__stack_log_file_path__, progname, (size_t)PATH_MAX);
+ }
+ if (!use_alternate_location) strlcat(__stack_log_file_path__, ".XXXXXX", (size_t)PATH_MAX);
+ strlcat(__stack_log_file_path__, stack_log_file_suffix, (size_t)PATH_MAX);
+
+ // Securely create the log file.
+ if ((index_file_descriptor = mkstemps(__stack_log_file_path__, (int)strlen(stack_log_file_suffix))) != -1) {
+ _malloc_printf(ASL_LEVEL_INFO, "stack logs being written into %s\n", __stack_log_file_path__);
+ created_log_location = __stack_log_file_path__;
+ } else {
+ _malloc_printf(ASL_LEVEL_INFO, "unable to create stack logs at %s\n", stack_log_location);
+ if (use_alternate_location) delete_logging_file(stack_log_reference_file);
+ stack_log_reference_file[0] = '\0';
+ stack_log_location[0] = '\0';
+ __stack_log_file_path__[0] = '\0';
+ created_log_location = NULL;
+ return created_log_location;
}
- if (!use_alternate_location) strlcat(stack_log_location, ".XXXXXX", (size_t)PATH_MAX);
- strlcat(stack_log_location, stack_log_file_suffix, (size_t)PATH_MAX);
// in the case where the user has specified an alternate location, drop a reference file
// in /tmp with the suffix 'stack_log_link_suffix' (".link") and save the path of the
// stack logging file there.
+ bool use_alternate_link_location = false;
if (use_alternate_location) {
strlcpy(stack_log_reference_file, _PATH_TMP, (size_t)PATH_MAX);
+ if (access(stack_log_reference_file, W_OK) == -1) {
+ strlcpy(stack_log_reference_file, stack_log_location, (size_t)PATH_MAX);
+ use_alternate_link_location = true;
+ }
strlcat(stack_log_reference_file, stack_log_file_base_name, (size_t)PATH_MAX);
append_int(stack_log_reference_file, pid, (size_t)PATH_MAX);
if (progname && progname[0] != '\0') {
strlcat(stack_log_reference_file, ".", (size_t)PATH_MAX);
strlcat(stack_log_reference_file, progname, (size_t)PATH_MAX);
}
+ if (!use_alternate_link_location)
+ strlcat(stack_log_reference_file, ".XXXXXX", (size_t)PATH_MAX);
strlcat(stack_log_reference_file, ".XXXXXX", (size_t)PATH_MAX);
strlcat(stack_log_reference_file, stack_log_link_suffix, (size_t)PATH_MAX);
int link_file_descriptor = mkstemps(stack_log_reference_file, (int)strlen(stack_log_link_suffix));
if (link_file_descriptor == -1) {
- _malloc_printf(ASL_LEVEL_INFO, "unable to create stack reference file at %s\n", stack_log_location);
- return NULL;
+ _malloc_printf(ASL_LEVEL_INFO, "unable to create stack reference file %s at %s\n",
+ stack_log_reference_file, stack_log_location);
+ } else {
+ ssize_t written = write(link_file_descriptor, __stack_log_file_path__, strlen(__stack_log_file_path__));
+ if (written < (ssize_t)strlen(__stack_log_file_path__)) {
+ _malloc_printf(ASL_LEVEL_INFO, "unable to write to stack reference file %s at %s\n",
+ stack_log_reference_file, stack_log_location);
+ } else {
+ const char *description_string = "\n(This is a reference file to the stack logs at the path above.)\n";
+ write(link_file_descriptor, description_string, strlen(description_string));
}
- ssize_t written = write(link_file_descriptor, stack_log_location, strlen(stack_log_location));
- if (written < (ssize_t)strlen(stack_log_location)) {
- _malloc_printf(ASL_LEVEL_INFO, "unable to write to stack reference file at %s\n", stack_log_location);
- return NULL;
}
- const char *description_string = "\n(This is a reference file to the stack logs at the path above.)\n";
- write(link_file_descriptor, description_string, strlen(description_string));
close(link_file_descriptor);
}
-
- // Securely create the log file.
- if ((index_file_descriptor = mkstemps(stack_log_location, (int)strlen(stack_log_file_suffix))) != -1) {
- _malloc_printf(ASL_LEVEL_INFO, "stack logs being written into %s\n", stack_log_location);
- created_log_location = stack_log_location;
- } else {
- _malloc_printf(ASL_LEVEL_INFO, "unable to create stack logs at %s\n", stack_log_location);
- if (use_alternate_location) delete_logging_file(stack_log_reference_file);
- stack_log_reference_file[0] = '\0';
- stack_log_location[0] = '\0';
- created_log_location = NULL;
+ if (use_alternate_link_location) {
+ _malloc_printf(ASL_LEVEL_INFO, "Please issue: cp %s %s\n", stack_log_reference_file, _PATH_TMP);
}
return created_log_location;
}
static void
delete_log_files(void)
{
- if (stack_log_location && stack_log_location[0]) {
- if (delete_logging_file(stack_log_location) == 0) {
- _malloc_printf(ASL_LEVEL_INFO, "stack logs deleted from %s\n", stack_log_location);
- index_file_path[0] = '\0';
+ if (__stack_log_file_path__ && __stack_log_file_path__[0]) {
+ if (delete_logging_file(__stack_log_file_path__) == 0) {
+ _malloc_printf(ASL_LEVEL_INFO, "stack logs deleted from %s\n", __stack_log_file_path__);
+ __stack_log_file_path__[0] = '\0';
} else {
- _malloc_printf(ASL_LEVEL_INFO, "unable to delete stack logs from %s\n", stack_log_location);
+ _malloc_printf(ASL_LEVEL_INFO, "unable to delete stack logs from %s\n", __stack_log_file_path__);
}
}
if (stack_log_reference_file && stack_log_reference_file[0]) {
// descriptor was closed on us. We need to reopen it
if (fd == index_file_descriptor) {
- file_to_reopen = index_file_path;
+ file_to_reopen = __stack_log_file_path__;
fd_to_reset = &index_file_descriptor;
} else {
// We don't know about this file. Return (and abort()).
while (remaining > 0) {
written = robust_write(index_file_descriptor, p, remaining);
if (written == -1) {
- _malloc_printf(ASL_LEVEL_INFO, "Unable to write to stack logging file %s (%s)\n", index_file_path, strerror(errno));
+ _malloc_printf(ASL_LEVEL_INFO, "Unable to write to stack logging file %s (%s)\n",
+ __stack_log_file_path__, strerror(errno));
disable_stack_logging();
return;
}
pre_write_buffers = (stack_buffer_shared_memory*)mmap(0, full_shared_mem_size, PROT_READ | PROT_WRITE, MAP_SHARED, shmid, (off_t)0);
close(shmid);
- if (!pre_write_buffers) {
+ if (MAP_FAILED == pre_write_buffers) {
_malloc_printf(ASL_LEVEL_INFO, "error mapping in shared memory for disk-based stack logging output buffers\n");
disable_stack_logging();
return;
}
-
+
// Store and use the buffer offsets in shared memory so that they can be accessed remotely
pre_write_buffers->start_index_offset = 0ull;
pre_write_buffers->next_free_index_buffer_offset = 0;
disable_stack_logging();
return;
}
-
- stack_buffer = (vm_address_t*)allocate_pages((uint64_t)round_page(sizeof(vm_address_t) * STACK_LOGGING_MAX_STACK_SIZE));
+
+ uint64_t stack_buffer_sz = (uint64_t)round_page(sizeof(vm_address_t) * STACK_LOGGING_MAX_STACK_SIZE);
+ stack_buffer = (vm_address_t*)allocate_pages(stack_buffer_sz);
if (!stack_buffer) {
_malloc_printf(ASL_LEVEL_INFO, "error while allocating stack trace buffer\n");
disable_stack_logging();
// malloc() can be called by the following, so these need to be done outside the stack_logging_lock but after the buffers have been set up.
atexit(delete_log_files); // atexit() can call malloc()
reap_orphaned_log_files(true); // this calls opendir() which calls malloc()
-
+
// this call ensures that the log files exist; analyzing processes will rely on this assumption.
if (create_log_file() == NULL) {
- disable_stack_logging();
+ /* postponement support requires cleaning up these structures now */
+ __destroy_uniquing_table(pre_write_buffers->uniquing_table);
+ deallocate_pages(stack_buffer, stack_buffer_sz);
+ stack_buffer = NULL;
+
+ munmap(pre_write_buffers, full_shared_mem_size);
+ pre_write_buffers = NULL;
+
+ if (!stack_logging_postponed) {
+ disable_stack_logging();
+ }
return;
}
}
void
__disk_stack_logging_log_stack(uint32_t type_flags, uintptr_t zone_ptr, uintptr_t size, uintptr_t ptr_arg, uintptr_t return_val, uint32_t num_hot_to_skip)
{
- if (!stack_logging_enable_logging) return;
+ if (!stack_logging_enable_logging || stack_logging_postponed) return;
// check incoming data
if (type_flags & stack_logging_type_alloc && type_flags & stack_logging_type_dealloc) {
prepare_to_log_stacks();
// since there could have been a fatal (to stack logging) error such as the log files not being created, check this variable before continuing
- if (!stack_logging_enable_logging) return;
+ if (!stack_logging_enable_logging || stack_logging_postponed) return;
+
vm_address_t self_thread = (vm_address_t)pthread_self(); // use pthread_self() rather than mach_thread_self() to avoid system call
// lock and enter
OSSpinLockUnlock(&stack_logging_lock);
}
+void
+__stack_logging_early_finished() {
+ stack_logging_finished_init = 1;
+ stack_logging_postponed = 0;
+}
+
boolean_t
-__stack_logging_locked()
+__stack_logging_locked()
{
bool acquired_lock = OSSpinLockTry(&stack_logging_lock);
if (acquired_lock) OSSpinLockUnlock(&stack_logging_lock);
close(shmid);
}
- if (shmid < 0 || cache->shmem == NULL) {
+ if (shmid < 0 || cache->shmem == MAP_FAILED) {
// failed to connect to the shared memory region; warn and continue.
_malloc_printf(ASL_LEVEL_INFO, "warning: unable to connect to remote process' shared memory; allocation histories may not be up-to-date.\n");
}
}
// if a snapshot is necessary, memcpy from remote frozen process' memory
- // note: there were two ways to do this – spin lock or suspend. suspend allows us to
+ // note: there were two ways to do this - spin lock or suspend. suspend allows us to
// analyze processes even if they were artificially suspended. with a lock, there'd be
// worry that the target was suspended with the lock taken.
if (update_snapshot) {
// In the stack log analysis process, find the stack logging files for target process <pid>
// by scanning the temporary directory for directory entries with names of the form "stack-logs.<pid>."
// If we find such a directory then open the stack logging files in there.
+// We might also have been passed the file path if the client first read it from __stack_log_file_path__
+// global variable in the target task, as will be needed if the .link cannot be put in /tmp.
static void
-open_log_files(pid_t pid, remote_task_file_streams *this_task_streams)
+open_log_files(pid_t pid, char* file_path, remote_task_file_streams *this_task_streams)
{
DIR *dp;
struct dirent *entry;
reap_orphaned_log_files(false); // reap any left-over log files (for non-existant processes, but not for this analysis process)
+ if (file_path != NULL) {
+ this_task_streams->index_file_stream = fopen(file_path, "r");
+ return;
+ }
+
if ((dp = opendir(_PATH_TMP)) == NULL) {
return;
}
}
static remote_task_file_streams*
-retain_file_streams_for_task(task_t task)
+retain_file_streams_for_task(task_t task, char* file_path)
{
if (task == MACH_PORT_NULL) return NULL;
remote_task_file_streams *this_task_streams = &remote_fds[next_remote_task_fd];
- open_log_files(pid, this_task_streams);
+ open_log_files(pid, file_path, this_task_streams);
// check if opens failed
if (this_task_streams->index_file_stream == NULL) {
#pragma mark - extern
+//
+// The following is used by client tools like malloc_history and Instruments to pass along the path
+// of the index file as read from the target task's __stack_log_file_path__ variable (set in this file)
+// Eventually, at a suitable point, this additional argument should just be added to the other APIs below.
+//
+kern_return_t
+__mach_stack_logging_set_file_path(task_t task, char* file_path)
+{
+ remote_task_file_streams *remote_fd = retain_file_streams_for_task(task, file_path);
+ if (remote_fd == NULL) {
+ return KERN_FAILURE;
+ }
+ return KERN_SUCCESS;
+}
+
kern_return_t
__mach_stack_logging_get_frames(task_t task, mach_vm_address_t address, mach_vm_address_t *stack_frames_buffer, uint32_t max_stack_frames, uint32_t *count)
{
- remote_task_file_streams *remote_fd = retain_file_streams_for_task(task);
+ remote_task_file_streams *remote_fd = retain_file_streams_for_task(task, NULL);
if (remote_fd == NULL) {
return KERN_FAILURE;
}
kern_return_t
__mach_stack_logging_enumerate_records(task_t task, mach_vm_address_t address, void enumerator(mach_stack_logging_record_t, void *), void *context)
{
- remote_task_file_streams *remote_fd = retain_file_streams_for_task(task);
+ remote_task_file_streams *remote_fd = retain_file_streams_for_task(task, NULL);
if (remote_fd == NULL) {
return KERN_FAILURE;
}
kern_return_t
__mach_stack_logging_frames_for_uniqued_stack(task_t task, uint64_t stack_identifier, mach_vm_address_t *stack_frames_buffer, uint32_t max_stack_frames, uint32_t *count)
{
- remote_task_file_streams *remote_fd = retain_file_streams_for_task(task);
+ remote_task_file_streams *remote_fd = retain_file_streams_for_task(task, NULL);
if (remote_fd == NULL) return KERN_FAILURE;
__unwind_stack_from_table_index(&remote_fd->cache->uniquing_table, stack_identifier, stack_frames_buffer, count, max_stack_frames);
fprintf(stderr, "sizeof stack_log_file_base_name: %lu\n", sizeof(stack_log_file_base_name)); total_globals += sizeof(stack_log_file_base_name);
fprintf(stderr, "sizeof stack_log_file_suffix: %lu\n", sizeof(stack_log_file_suffix)); total_globals += sizeof(stack_log_file_suffix);
fprintf(stderr, "sizeof stack_log_link_suffix: %lu\n", sizeof(stack_log_link_suffix)); total_globals += sizeof(stack_log_link_suffix);
- fprintf(stderr, "sizeof stack_log_location: %lu\n", sizeof(stack_log_location)); total_globals += sizeof(stack_log_location);
- fprintf(stderr, "sizeof stack_log_reference_file: %lu\n", sizeof(stack_log_reference_file)); total_globals += sizeof(stack_log_reference_file);
- fprintf(stderr, "sizeof index_file_path: %lu\n", sizeof(index_file_path)); total_globals += sizeof(index_file_path);
+ fprintf(stderr, "sizeof stack_log_location: %lu\n", (size_t)PATH_MAX); total_globals += (size_t)PATH_MAX;
+ fprintf(stderr, "sizeof stack_log_reference_file: %lu\n", (size_t)PATH_MAX); total_globals += (size_t)PATH_MAX;
+ fprintf(stderr, "sizeof __stack_log_file_path__ (index_file_path): %lu\n", (size_t)PATH_MAX); total_globals += (size_t)PATH_MAX;
fprintf(stderr, "sizeof index_file_descriptor: %lu\n", sizeof(index_file_descriptor)); total_globals += sizeof(index_file_descriptor);
fprintf(stderr, "sizeof remote_fds: %lu\n", sizeof(remote_fds)); total_globals += sizeof(remote_fds);
fprintf(stderr, "sizeof next_remote_task_fd: %lu\n", sizeof(next_remote_task_fd)); total_globals += sizeof(next_remote_task_fd);
projects / apple / libc.git / blobdiff