#ifdef HAVE_PRCTL
# include <sys/prctl.h>
#endif
+#include <asm/unistd.h>
+#include "scno.h"
#include "ptrace.h"
#include "printsiginfo.h"
bool stack_trace_enabled = false;
#endif
-#if defined __NR_tkill
-# define my_tkill(tid, sig) syscall(__NR_tkill, (tid), (sig))
-#else
- /* kill() may choose arbitrarily the target task of the process group
- while we later wait on a that specific TID. PID process waits become
- TID task specific waits for a process under ptrace(2). */
-# warning "tkill(2) not available, risk of strace hangs!"
-# define my_tkill(tid, sig) kill((tid), (sig))
-#endif
+#define my_tkill(tid, sig) syscall(__NR_tkill, (tid), (sig))
/* Glue for systems without a MMU that cannot provide fork() */
#if !defined(HAVE_FORK)
cflag_t cflag = CFLAG_NONE;
unsigned int followfork = 0;
-unsigned int ptrace_setoptions = PTRACE_O_TRACESYSGOOD | PTRACE_O_TRACEEXEC;
+unsigned int ptrace_setoptions = PTRACE_O_TRACESYSGOOD | PTRACE_O_TRACEEXEC
+ | PTRACE_O_TRACEEXIT;
unsigned int xflag = 0;
bool debug_flag = 0;
bool Tflag = 0;
unsigned int show_fd_path = 0;
static bool detach_on_execve = 0;
-/* Are we "strace PROG" and need to skip detach on first execve? */
-static bool skip_one_b_execve = 0;
-/* Are we "strace PROG" and need to hide everything until execve? */
-bool hide_log_until_execve = 0;
-static int exit_code = 0;
+static int exit_code;
static int strace_child = 0;
static int strace_tracer_pid = 0;
#endif /* HAVE_STERRROR */
static void
-usage(FILE *ofp, int exitval)
+print_version(void)
+{
+ printf("%s -- version %s\n"
+ "Copyright (C) %s The strace developers <%s>.\n"
+ "This is free software; see the source for copying conditions. There is NO\n"
+ "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n",
+ PACKAGE_NAME, PACKAGE_VERSION, "1991-2017", PACKAGE_URL);
+}
+
+static void
+usage(void)
{
- fprintf(ofp, "\
-usage: strace [-CdffhiqrtttTvVxxy] [-I n] [-e expr]...\n\
+ printf("\
+usage: strace [-CdffhiqrtttTvVwxxy] [-I n] [-e expr]...\n\
[-a column] [-o file] [-s strsize] [-P path]...\n\
-p pid... / [-D] [-E var=val]... [-u username] PROG [ARGS]\n\
- or: strace -c[df] [-I n] [-e expr]... [-O overhead] [-S sortby]\n\
+ or: strace -c[dfw] [-I n] [-e expr]... [-O overhead] [-S sortby]\n\
-p pid... / [-D] [-E var=val]... [-u username] PROG [ARGS]\n\
--c -- count time, calls, and errors for each syscall and report summary\n\
--C -- like -c but also print regular output\n\
--w -- summarise syscall latency (default is system time)\n\
--d -- enable debug output to stderr\n\
--D -- run tracer process as a detached grandchild, not as parent\n\
--f -- follow forks, -ff -- with output into separate files\n\
--i -- print instruction pointer at time of syscall\n\
--q -- suppress messages about attaching, detaching, etc.\n\
--r -- print relative timestamp, -t -- absolute timestamp, -tt -- with usecs\n\
--T -- print time spent in each syscall\n\
--v -- verbose mode: print unabbreviated argv, stat, termios, etc. args\n\
--x -- print non-ascii strings in hex, -xx -- print all strings in hex\n\
--y -- print paths associated with file descriptor arguments\n\
--yy -- print ip:port pairs associated with socket file descriptors\n\
--h -- print help message, -V -- print version\n\
--a column -- alignment COLUMN for printing syscall results (default %d)\n\
--b execve -- detach on this syscall\n\
--e expr -- a qualifying expression: option=[!]all or option=[!]val1[,val2]...\n\
- options: trace, abbrev, verbose, raw, signal, read, write\n\
--I interruptible --\n\
- 1: no signals are blocked\n\
- 2: fatal signals are blocked while decoding syscall (default)\n\
- 3: fatal signals are always blocked (default if '-o FILE PROG')\n\
- 4: fatal signals and SIGTSTP (^Z) are always blocked\n\
- (useful to make 'strace -o FILE PROG' not stop on ^Z)\n\
--o file -- send trace output to FILE instead of stderr\n\
--O overhead -- set overhead for tracing syscalls to OVERHEAD usecs\n\
--p pid -- trace process with process id PID, may be repeated\n\
--s strsize -- limit length of print strings to STRSIZE chars (default %d)\n\
--S sortby -- sort syscall counts by: time, calls, name, nothing (default %s)\n\
--u username -- run command as username handling setuid and/or setgid\n\
--E var=val -- put var=val in the environment for command\n\
--E var -- remove var from the environment for command\n\
--P path -- trace accesses to path\n\
+\n\
+Output format:\n\
+ -a column alignment COLUMN for printing syscall results (default %d)\n\
+ -i print instruction pointer at time of syscall\n\
"
#ifdef USE_LIBUNWIND
-"-k obtain stack trace between each syscall (experimental)\n\
+"\
+ -k obtain stack trace between each syscall (experimental)\n\
"
#endif
+"\
+ -o file send trace output to FILE instead of stderr\n\
+ -q suppress messages about attaching, detaching, etc.\n\
+ -r print relative timestamp\n\
+ -s strsize limit length of print strings to STRSIZE chars (default %d)\n\
+ -t print absolute timestamp\n\
+ -tt print absolute timestamp with usecs\n\
+ -T print time spent in each syscall\n\
+ -x print non-ascii strings in hex\n\
+ -xx print all strings in hex\n\
+ -y print paths associated with file descriptor arguments\n\
+ -yy print protocol specific information associated with socket file descriptors\n\
+\n\
+Statistics:\n\
+ -c count time, calls, and errors for each syscall and report summary\n\
+ -C like -c but also print regular output\n\
+ -O overhead set overhead for tracing syscalls to OVERHEAD usecs\n\
+ -S sortby sort syscall counts by: time, calls, name, nothing (default %s)\n\
+ -w summarise syscall latency (default is system time)\n\
+\n\
+Filtering:\n\
+ -e expr a qualifying expression: option=[!]all or option=[!]val1[,val2]...\n\
+ options: trace, abbrev, verbose, raw, signal, read, write, fault\n\
+ -P path trace accesses to path\n\
+\n\
+Tracing:\n\
+ -b execve detach on execve syscall\n\
+ -D run tracer process as a detached grandchild, not as parent\n\
+ -f follow forks\n\
+ -ff follow forks with output into separate files\n\
+ -I interruptible\n\
+ 1: no signals are blocked\n\
+ 2: fatal signals are blocked while decoding syscall (default)\n\
+ 3: fatal signals are always blocked (default if '-o FILE PROG')\n\
+ 4: fatal signals and SIGTSTP (^Z) are always blocked\n\
+ (useful to make 'strace -o FILE PROG' not stop on ^Z)\n\
+\n\
+Startup:\n\
+ -E var remove var from the environment for command\n\
+ -E var=val put var=val in the environment for command\n\
+ -p pid trace process with process id PID, may be repeated\n\
+ -u username run command as username handling setuid and/or setgid\n\
+\n\
+Miscellaneous:\n\
+ -d enable debug output to stderr\n\
+ -v verbose mode: print unabbreviated argv, stat, termios, etc. args\n\
+ -h print help message\n\
+ -V print version\n\
+"
/* ancient, no one should use it
-F -- attempt to follow vforks (deprecated, use -f)\n\
*/
-z -- print only succeeding syscalls\n\
*/
, DEFAULT_ACOLUMN, DEFAULT_STRLEN, DEFAULT_SORTBY);
- exit(exitval);
+ exit(0);
}
static void ATTRIBUTE_NORETURN
die();
}
+void error_msg_and_help(const char *fmt, ...)
+{
+ if (fmt != NULL) {
+ va_list p;
+ va_start(p, fmt);
+ verror_msg(0, fmt, p);
+ }
+ fprintf(stderr, "Try '%s -h' for more information.\n", progname);
+ die();
+}
+
void perror_msg(const char *fmt, ...)
{
va_list p;
static void
error_opt_arg(int opt, const char *arg)
{
- error_msg_and_die("Invalid -%c argument: '%s'", opt, arg);
+ error_msg_and_help("invalid -%c argument: '%s'", opt, arg);
}
-#if USE_SEIZE
+static const char *ptrace_attach_cmd;
+
static int
ptrace_attach_or_seize(int pid)
{
+#if USE_SEIZE
int r;
if (!use_seize)
- return ptrace(PTRACE_ATTACH, pid, 0L, 0L);
+ return ptrace_attach_cmd = "PTRACE_ATTACH",
+ ptrace(PTRACE_ATTACH, pid, 0L, 0L);
r = ptrace(PTRACE_SEIZE, pid, 0L, (unsigned long) ptrace_setoptions);
if (r)
- return r;
+ return ptrace_attach_cmd = "PTRACE_SEIZE", r;
r = ptrace(PTRACE_INTERRUPT, pid, 0L, 0L);
- return r;
-}
+ return ptrace_attach_cmd = "PTRACE_INTERRUPT", r;
#else
-# define ptrace_attach_or_seize(pid) ptrace(PTRACE_ATTACH, (pid), 0, 0)
+ return ptrace_attach_cmd = "PTRACE_ATTACH",
+ ptrace(PTRACE_ATTACH, pid, 0L, 0L);
#endif
+}
/*
* Used when we want to unblock stopped traced process.
* Otherwise prints error message and returns -1.
*/
static int
-ptrace_restart(int op, struct tcb *tcp, int sig)
+ptrace_restart(const unsigned int op, struct tcb *const tcp, unsigned int sig)
{
int err;
const char *msg;
errno = 0;
- ptrace(op, tcp->pid, (void *) 0, (long) sig);
+ ptrace(op, tcp->pid, 0L, (unsigned long) sig);
err = errno;
if (!err)
return 0;
- msg = "SYSCALL";
- if (op == PTRACE_CONT)
- msg = "CONT";
- if (op == PTRACE_DETACH)
- msg = "DETACH";
-#ifdef PTRACE_LISTEN
- if (op == PTRACE_LISTEN)
- msg = "LISTEN";
-#endif
+ switch (op) {
+ case PTRACE_CONT:
+ msg = "CONT";
+ break;
+ case PTRACE_DETACH:
+ msg = "DETACH";
+ break;
+ case PTRACE_LISTEN:
+ msg = "LISTEN";
+ break;
+ default:
+ msg = "SYSCALL";
+ }
+
/*
* Why curcol != 0? Otherwise sometimes we get this:
*
if (err == ESRCH)
return 0;
errno = err;
- perror_msg("ptrace(PTRACE_%s,pid:%d,sig:%d)", msg, tcp->pid, sig);
+ perror_msg("ptrace(PTRACE_%s,pid:%d,sig:%u)", msg, tcp->pid, sig);
return -1;
}
fcntl(fd, F_SETFD, newflags); /* never fails */
}
-static void kill_save_errno(pid_t pid, int sig)
+static void
+kill_save_errno(pid_t pid, int sig)
{
int saved_errno = errno;
va_start(args, fmt);
if (current_tcp) {
- int n = strace_vfprintf(current_tcp->outf, fmt, args);
+ int n = vfprintf(current_tcp->outf, fmt, args);
if (n < 0) {
if (current_tcp->outf != stderr)
perror_msg("%s", outfname);
static void
expand_tcbtab(void)
{
- /* Allocate some more TCBs and expand the table.
+ /* Allocate some (more) TCBs (and expand the table).
We don't want to relocate the TCBs because our
callers have pointers and it would be a pain.
So tcbtab is a table of pointers. Since we never
free the TCBs, we allocate a single chunk of many. */
- unsigned int i = tcbtabsize;
- struct tcb *newtcbs = xcalloc(tcbtabsize, sizeof(newtcbs[0]));
- struct tcb **newtab = xreallocarray(tcbtab, tcbtabsize * 2,
- sizeof(tcbtab[0]));
- tcbtabsize *= 2;
- tcbtab = newtab;
- while (i < tcbtabsize)
- tcbtab[i++] = newtcbs++;
+ unsigned int new_tcbtabsize, alloc_tcbtabsize;
+ struct tcb *newtcbs;
+
+ if (tcbtabsize) {
+ alloc_tcbtabsize = tcbtabsize;
+ new_tcbtabsize = tcbtabsize * 2;
+ } else {
+ new_tcbtabsize = alloc_tcbtabsize = 1;
+ }
+
+ newtcbs = xcalloc(alloc_tcbtabsize, sizeof(newtcbs[0]));
+ tcbtab = xreallocarray(tcbtab, new_tcbtabsize, sizeof(tcbtab[0]));
+ while (tcbtabsize < new_tcbtabsize)
+ tcbtab[tcbtabsize++] = newtcbs++;
}
static struct tcb *
error_msg_and_die("bug in alloctcb");
}
+void *
+get_tcb_priv_data(const struct tcb *tcp)
+{
+ return tcp->_priv_data;
+}
+
+int
+set_tcb_priv_data(struct tcb *tcp, void *const priv_data,
+ void (*const free_priv_data)(void *))
+{
+ if (tcp->_priv_data)
+ return -1;
+
+ tcp->_free_priv_data = free_priv_data;
+ tcp->_priv_data = priv_data;
+
+ return 0;
+}
+
+void
+free_tcb_priv_data(struct tcb *tcp)
+{
+ if (tcp->_priv_data) {
+ if (tcp->_free_priv_data) {
+ tcp->_free_priv_data(tcp->_priv_data);
+ tcp->_free_priv_data = NULL;
+ }
+ tcp->_priv_data = NULL;
+ }
+}
+
static void
droptcb(struct tcb *tcp)
{
if (tcp->pid == 0)
return;
+ int p;
+ for (p = 0; p < SUPPORTED_PERSONALITIES; ++p)
+ free(tcp->inject_vec[p]);
+
+ free_tcb_priv_data(tcp);
+
#ifdef USE_LIBUNWIND
if (stack_trace_enabled) {
unwind_tcb_fin(tcp);
* before detaching. Arghh. We go through hoops
* to make a clean break of things.
*/
-#if defined(SPARC)
-# undef PTRACE_DETACH
-# define PTRACE_DETACH PTRACE_SUNDETACH
-#endif
if (!(tcp->flags & TCB_ATTACHED))
goto drop;
}
}
+static void
+attach_tcb(struct tcb *const tcp)
+{
+ if (ptrace_attach_or_seize(tcp->pid) < 0) {
+ perror_msg("attach: ptrace(%s, %d)",
+ ptrace_attach_cmd, tcp->pid);
+ droptcb(tcp);
+ return;
+ }
+
+ tcp->flags |= TCB_ATTACHED | TCB_STARTUP | post_attach_sigstop;
+ newoutf(tcp);
+ if (debug_flag)
+ error_msg("attach to pid %d (main) succeeded", tcp->pid);
+
+ char procdir[sizeof("/proc/%d/task") + sizeof(int) * 3];
+ DIR *dir;
+ unsigned int ntid = 0, nerr = 0;
+
+ if (followfork && tcp->pid != strace_child &&
+ sprintf(procdir, "/proc/%d/task", tcp->pid) > 0 &&
+ (dir = opendir(procdir)) != NULL) {
+ struct_dirent *de;
+
+ while ((de = read_dir(dir)) != NULL) {
+ if (de->d_fileno == 0)
+ continue;
+
+ int tid = string_to_uint(de->d_name);
+ if (tid <= 0 || tid == tcp->pid)
+ continue;
+
+ ++ntid;
+ if (ptrace_attach_or_seize(tid) < 0) {
+ ++nerr;
+ if (debug_flag)
+ perror_msg("attach: ptrace(%s, %d)",
+ ptrace_attach_cmd, tid);
+ continue;
+ }
+ if (debug_flag)
+ error_msg("attach to pid %d succeeded", tid);
+
+ struct tcb *tid_tcp = alloctcb(tid);
+ tid_tcp->flags |= TCB_ATTACHED | TCB_STARTUP |
+ post_attach_sigstop;
+ newoutf(tid_tcp);
+ }
+
+ closedir(dir);
+ }
+
+ if (!qflag) {
+ if (ntid > nerr)
+ error_msg("Process %u attached"
+ " with %u threads",
+ tcp->pid, ntid - nerr + 1);
+ else
+ error_msg("Process %u attached",
+ tcp->pid);
+ }
+}
+
static void
startup_attach(void)
{
+ pid_t parent_pid = strace_tracer_pid;
unsigned int tcbi;
struct tcb *tcp;
if (tcp->flags & TCB_ATTACHED)
continue; /* no, we already attached it */
- if (followfork && !daemonized_tracer) {
- char procdir[sizeof("/proc/%d/task") + sizeof(int) * 3];
- DIR *dir;
-
- sprintf(procdir, "/proc/%d/task", tcp->pid);
- dir = opendir(procdir);
- if (dir != NULL) {
- unsigned int ntid = 0, nerr = 0;
- struct_dirent *de;
-
- while ((de = read_dir(dir)) != NULL) {
- struct tcb *cur_tcp;
- int tid;
-
- if (de->d_fileno == 0)
- continue;
- /* we trust /proc filesystem */
- tid = atoi(de->d_name);
- if (tid <= 0)
- continue;
- ++ntid;
- if (ptrace_attach_or_seize(tid) < 0) {
- ++nerr;
- if (debug_flag)
- error_msg("attach to pid %d failed", tid);
- continue;
- }
- if (debug_flag)
- error_msg("attach to pid %d succeeded", tid);
- cur_tcp = tcp;
- if (tid != tcp->pid)
- cur_tcp = alloctcb(tid);
- cur_tcp->flags |= TCB_ATTACHED | TCB_STARTUP | post_attach_sigstop;
- newoutf(cur_tcp);
- }
- closedir(dir);
- if (interactive) {
- sigprocmask(SIG_SETMASK, &empty_set, NULL);
- if (interrupted)
- goto ret;
- sigprocmask(SIG_BLOCK, &blocked_set, NULL);
- }
- ntid -= nerr;
- if (ntid == 0) {
- perror_msg("attach: ptrace(PTRACE_ATTACH, ...)");
- droptcb(tcp);
- continue;
- }
- if (!qflag) {
- error_msg(ntid > 1
-? "Process %u attached with %u threads"
-: "Process %u attached",
- tcp->pid, ntid);
- }
- if (!(tcp->flags & TCB_ATTACHED)) {
- /* -p PID, we failed to attach to PID itself
- * but did attach to some of its sibling threads.
- * Drop PID's tcp.
- */
- droptcb(tcp);
- }
- continue;
- } /* if (opendir worked) */
- } /* if (-f) */
- if (ptrace_attach_or_seize(tcp->pid) < 0) {
- perror_msg("attach: ptrace(PTRACE_ATTACH, ...)");
+ if (tcp->pid == parent_pid || tcp->pid == strace_tracer_pid) {
+ errno = EPERM;
+ perror_msg("attach: pid %d", tcp->pid);
droptcb(tcp);
continue;
}
- tcp->flags |= TCB_ATTACHED | TCB_STARTUP | post_attach_sigstop;
- newoutf(tcp);
- if (debug_flag)
- error_msg("attach to pid %d (main) succeeded", tcp->pid);
- if (daemonized_tracer) {
- /*
- * Make parent go away.
- * Also makes grandparent's wait() unblock.
- */
- kill(getppid(), SIGKILL);
- }
+ attach_tcb(tcp);
- if (!qflag)
- error_msg("Process %u attached", tcp->pid);
+ if (interactive) {
+ sigprocmask(SIG_SETMASK, &empty_set, NULL);
+ if (interrupted)
+ goto ret;
+ sigprocmask(SIG_BLOCK, &blocked_set, NULL);
+ }
} /* for each tcbtab[] */
+ if (daemonized_tracer) {
+ /*
+ * Make parent go away.
+ * Also makes grandparent's wait() unblock.
+ */
+ kill(parent_pid, SIGKILL);
+ strace_child = 0;
+ }
+
ret:
if (interactive)
sigprocmask(SIG_SETMASK, &empty_set, NULL);
perror_msg_and_die("exec");
}
+/*
+ * Open a dummy descriptor for use as a placeholder.
+ * The descriptor is O_RDONLY with FD_CLOEXEC flag set.
+ * A read attempt from such descriptor ends with EOF,
+ * a write attempt is rejected with EBADF.
+ */
+static int
+open_dummy_desc(void)
+{
+ int fds[2];
+
+ if (pipe(fds))
+ perror_msg_and_die("pipe");
+ close(fds[1]);
+ set_cloexec_flag(fds[0]);
+ return fds[0];
+}
+
+/* placeholder fds status for stdin and stdout */
+static bool fd_is_placeholder[2];
+
+/*
+ * Ensure that all standard file descriptors are open by opening placeholder
+ * file descriptors for those standard file descriptors that are not open.
+ *
+ * The information which descriptors have been made open is saved
+ * in fd_is_placeholder for later use.
+ */
+static void
+ensure_standard_fds_opened(void)
+{
+ int fd;
+
+ while ((fd = open_dummy_desc()) <= 2) {
+ if (fd == 2)
+ break;
+ fd_is_placeholder[fd] = true;
+ }
+
+ if (fd > 2)
+ close(fd);
+}
+
+/*
+ * Redirect stdin and stdout unless they have been opened earlier
+ * by ensure_standard_fds_opened as placeholders.
+ */
+static void
+redirect_standard_fds(void)
+{
+ int i;
+
+ /*
+ * It might be a good idea to redirect stderr as well,
+ * but we sometimes need to print error messages.
+ */
+ for (i = 0; i <= 1; ++i) {
+ if (!fd_is_placeholder[i]) {
+ close(i);
+ open_dummy_desc();
+ }
+ }
+}
+
static void
startup_child(char **argv)
{
}
if (!WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP) {
kill_save_errno(pid, SIGKILL);
- perror_msg_and_die("Unexpected wait status %x", status);
+ perror_msg_and_die("Unexpected wait status %#x",
+ status);
}
}
/* Else: NOMMU case, we have no way to sync.
if (ptrace_attach_or_seize(pid)) {
kill_save_errno(pid, SIGKILL);
- perror_msg_and_die("Can't attach to %d", pid);
+ perror_msg_and_die("attach: ptrace(%s, %d)",
+ ptrace_attach_cmd, pid);
}
if (!NOMMU_SYSTEM)
kill(pid, SIGCONT);
}
tcp = alloctcb(pid);
- if (!NOMMU_SYSTEM)
- tcp->flags |= TCB_ATTACHED | TCB_STARTUP | post_attach_sigstop;
- else
- tcp->flags |= TCB_ATTACHED | TCB_STARTUP;
+ tcp->flags |= TCB_ATTACHED | TCB_STARTUP
+ | TCB_SKIP_DETACH_ON_FIRST_EXEC
+ | (NOMMU_SYSTEM ? 0 : (TCB_HIDE_LOG | post_attach_sigstop));
newoutf(tcp);
}
else {
- /* With -D, we are *child* here, IOW: different pid. Fetch it: */
+ /* With -D, we are *child* here, the tracee is our parent. */
+ strace_child = strace_tracer_pid;
strace_tracer_pid = getpid();
- /* The tracee is our parent: */
- pid = getppid();
- alloctcb(pid);
+ tcp = alloctcb(strace_child);
+ tcp->flags |= TCB_SKIP_DETACH_ON_FIRST_EXEC | TCB_HIDE_LOG;
/* attaching will be done later, by startup_attach */
/* note: we don't do newoutf(tcp) here either! */
* to create a genuine separate stack and execute on it.
*/
}
+ /*
+ * A case where straced process is part of a pipe:
+ * { sleep 1; yes | head -n99999; } | strace -o/dev/null sh -c 'exec <&-; sleep 9'
+ * If strace won't close its fd#0, closing it in tracee is not enough:
+ * the pipe is still open, it has a reader. Thus, "head" will not get its
+ * SIGPIPE at once, on the first write.
+ *
+ * Preventing it by redirecting strace's stdin/out.
+ * (Don't leave fds 0 and 1 closed, this is bad practice: future opens
+ * will reuse them, unexpectedly making a newly opened object "stdin").
+ */
+ redirect_standard_fds();
}
#if USE_SEIZE
if (WIFSIGNALED(status)) {
return;
}
- error_msg_and_die("%s: unexpected wait status %x",
- __func__, status);
+ error_msg_and_die("%s: unexpected wait status %#x",
+ __func__, status);
}
}
#else /* !USE_SEIZE */
static void ATTRIBUTE_NOINLINE
init(int argc, char *argv[])
{
- struct tcb *tcp;
int c, i;
int optF = 0;
- unsigned int tcbi;
struct sigaction sa;
progname = argv[0] ? argv[0] : "strace";
os_release = get_os_release();
- /* Allocate the initial tcbtab. */
- tcbtabsize = argc; /* Surely enough for all -p args. */
- tcbtab = xcalloc(tcbtabsize, sizeof(tcbtab[0]));
- tcp = xcalloc(tcbtabsize, sizeof(*tcp));
- for (tcbi = 0; tcbi < tcbtabsize; tcbi++)
- tcbtab[tcbi] = tcp++;
-
shared_log = stderr;
set_sortby(DEFAULT_SORTBY);
set_personality(DEFAULT_PERSONALITY);
break;
case 'c':
if (cflag == CFLAG_BOTH) {
- error_msg_and_die("-c and -C are mutually exclusive");
+ error_msg_and_help("-c and -C are mutually exclusive");
}
cflag = CFLAG_ONLY_STATS;
break;
case 'C':
if (cflag == CFLAG_ONLY_STATS) {
- error_msg_and_die("-c and -C are mutually exclusive");
+ error_msg_and_help("-c and -C are mutually exclusive");
}
cflag = CFLAG_BOTH;
break;
followfork++;
break;
case 'h':
- usage(stdout, 0);
+ usage();
break;
case 'i':
iflag = 1;
break;
case 'r':
rflag = 1;
- /* fall through to tflag++ */
+ break;
case 't':
tflag++;
break;
qualify("abbrev=none");
break;
case 'V':
- printf("%s -- version %s\n", PACKAGE_NAME, VERSION);
+ print_version();
exit(0);
break;
case 'z':
die_out_of_memory();
break;
case 'I':
- opt_intr = string_to_uint(optarg);
- if (opt_intr <= 0 || opt_intr >= NUM_INTR_OPTS)
+ opt_intr = string_to_uint_upto(optarg, NUM_INTR_OPTS - 1);
+ if (opt_intr <= 0)
error_opt_arg(c, optarg);
break;
default:
- usage(stderr, 1);
+ error_msg_and_help(NULL);
break;
}
}
memset(acolumn_spaces, ' ', acolumn);
acolumn_spaces[acolumn] = '\0';
- /* Must have PROG [ARGS], or -p PID. Not both. */
- if (!argv[0] == !nprocs)
- usage(stderr, 1);
+ if (!argv[0] && !nprocs) {
+ error_msg_and_help("must have PROG [ARGS] or -p PID");
+ }
- if (nprocs != 0 && daemonized_tracer) {
- error_msg_and_die("-D and -p are mutually exclusive");
+ if (!argv[0] && daemonized_tracer) {
+ error_msg_and_help("PROG [ARGS] must be specified with -D");
}
if (!followfork)
followfork = optF;
if (followfork >= 2 && cflag) {
- error_msg_and_die("(-c or -C) and -ff are mutually exclusive");
+ error_msg_and_help("(-c or -C) and -ff are mutually exclusive");
}
if (count_wallclock && !cflag) {
- error_msg_and_die("-w must be given with (-c or -C)");
+ error_msg_and_help("-w must be given with (-c or -C)");
}
if (cflag == CFLAG_ONLY_STATS) {
error_msg("-%c has no effect with -c", 'y');
}
+ if (rflag) {
+ if (tflag > 1)
+ error_msg("-tt has no effect with -r");
+ tflag = 1;
+ }
+
#ifdef USE_LIBUNWIND
- if (stack_trace_enabled)
+ if (stack_trace_enabled) {
+ unsigned int tcbi;
+
unwind_init();
+ for (tcbi = 0; tcbi < tcbtabsize; ++tcbi) {
+ unwind_tcb_init(tcbtab[tcbi]);
+ }
+ }
#endif
/* See if they want to run as another user. */
error_msg("ptrace_setoptions = %#x", ptrace_setoptions);
test_ptrace_seize();
+ /*
+ * Is something weird with our stdin and/or stdout -
+ * for example, may they be not open? In this case,
+ * ensure that none of the future opens uses them.
+ *
+ * This was seen in the wild when /proc/sys/kernel/core_pattern
+ * was set to "|/bin/strace -o/tmp/LOG PROG":
+ * kernel runs coredump helper with fd#0 open but fd#1 closed (!),
+ * therefore LOG gets opened to fd#1, and fd#1 is closed by
+ * "don't hold up stdin/out open" code soon after.
+ */
+ ensure_standard_fds_opened();
+
/* Check if they want to redirect the output. */
if (outfname) {
/* See if they want to pipe the output. */
* when using popen, so prohibit it.
*/
if (followfork >= 2)
- error_msg_and_die("Piping the output and -ff are mutually exclusive");
+ error_msg_and_help("piping the output and -ff are mutually exclusive");
shared_log = strace_popen(outfname + 1);
}
else if (followfork < 2)
}
if (!outfname || outfname[0] == '|' || outfname[0] == '!') {
- char *buf = xmalloc(BUFSIZ);
- setvbuf(shared_log, buf, _IOLBF, BUFSIZ);
+ setvbuf(shared_log, NULL, _IOLBF, 0);
}
if (outfname && argv[0]) {
if (!opt_intr)
opt_intr = INTR_WHILE_WAIT;
/* argv[0] -pPID -oFILE Default interactive setting
- * yes 0 0 INTR_WHILE_WAIT
+ * yes * 0 INTR_WHILE_WAIT
* no 1 0 INTR_WHILE_WAIT
- * yes 0 1 INTR_NEVER
+ * yes * 1 INTR_NEVER
* no 1 1 INTR_WHILE_WAIT
*/
* in the startup_child() mode we kill the spawned process anyway.
*/
if (argv[0]) {
- if (!NOMMU_SYSTEM || daemonized_tracer)
- hide_log_until_execve = 1;
- skip_one_b_execve = 1;
startup_child(argv);
}
/* This can happen if a clone call used
* CLONE_PTRACE itself.
*/
- ptrace(PTRACE_CONT, pid, (char *) 0, 0);
+ ptrace(PTRACE_CONT, pid, NULL, 0);
error_msg("Stop of unknown pid %u seen, PTRACE_CONTed it", pid);
return NULL;
}
struct tcb *execve_thread;
long old_pid = 0;
- if (ptrace(PTRACE_GETEVENTMSG, pid, NULL, (long) &old_pid) < 0)
+ if (ptrace(PTRACE_GETEVENTMSG, pid, NULL, &old_pid) < 0)
return tcp;
/* Avoid truncation in pid2tcb() param passing */
if (old_pid <= 0 || old_pid == pid)
}
if (cflag != CFLAG_ONLY_STATS
- && (qual_flags[WTERMSIG(status)] & QUAL_SIGNAL)
- ) {
+ && is_number_in_set(WTERMSIG(status), &signal_set)) {
printleader(tcp);
#ifdef WCOREDUMP
tprintf("+++ killed by %s %s+++\n",
print_stopped(struct tcb *tcp, const siginfo_t *si, const unsigned int sig)
{
if (cflag != CFLAG_ONLY_STATS
- && !hide_log_until_execve
- && (qual_flags[sig] & QUAL_SIGNAL)
- ) {
+ && !hide_log(tcp)
+ && is_number_in_set(sig, &signal_set)) {
printleader(tcp);
if (si) {
tprintf("--- %s ", signame(sig));
- printsiginfo(si, verbose(tcp));
+ printsiginfo(si);
tprints(" ---\n");
} else
tprintf("--- stopped by %s ---\n", signame(sig));
}
}
+static void
+print_event_exit(struct tcb *tcp)
+{
+ if (entering(tcp) || filtered(tcp) || hide_log(tcp)
+ || cflag == CFLAG_ONLY_STATS) {
+ return;
+ }
+
+ if (followfork < 2 && printing_tcp && printing_tcp != tcp
+ && printing_tcp->curcol != 0) {
+ current_tcp = printing_tcp;
+ tprints(" <unfinished ...>\n");
+ fflush(printing_tcp->outf);
+ printing_tcp->curcol = 0;
+ current_tcp = tcp;
+ }
+
+ if ((followfork < 2 && printing_tcp != tcp)
+ || (tcp->flags & TCB_REPRINT)) {
+ tcp->flags &= ~TCB_REPRINT;
+ printleader(tcp);
+ tprintf("<... %s resumed>", tcp->s_ent->sys_name);
+ }
+
+ if (!(tcp->sys_func_rval & RVAL_DECODED)) {
+ /*
+ * The decoder has probably decided to print something
+ * on exiting syscall which is not going to happen.
+ */
+ tprints(" <unfinished ...>");
+ }
+ tprints(") ");
+ tabto();
+ tprints("= ?\n");
+ line_ended();
+}
+
/* Returns true iff the main trace loop has to continue. */
static bool
trace(void)
if (os_release >= KERNEL_VERSION(3,0,0))
tcp = maybe_switch_tcbs(tcp, pid);
- if (detach_on_execve && !skip_one_b_execve) {
- detach(tcp); /* do "-b execve" thingy */
- return true;
+ if (detach_on_execve) {
+ if (tcp->flags & TCB_SKIP_DETACH_ON_FIRST_EXEC) {
+ tcp->flags &= ~TCB_SKIP_DETACH_ON_FIRST_EXEC;
+ } else {
+ detach(tcp); /* do "-b execve" thingy */
+ return true;
+ }
}
- skip_one_b_execve = 0;
}
/* Set current output file */
sig = WSTOPSIG(status);
- if (event != 0) {
- /* Ptrace event */
+ switch (event) {
+ case 0:
+ break;
+ case PTRACE_EVENT_EXIT:
+ print_event_exit(tcp);
+ goto restart_tracee_with_sig_0;
#if USE_SEIZE
- if (event == PTRACE_EVENT_STOP) {
+ case PTRACE_EVENT_STOP:
/*
* PTRACE_INTERRUPT-stop or group-stop.
* PTRACE_INTERRUPT-stop has sig == SIGTRAP here.
stopped = true;
goto show_stopsig;
}
- }
+ /* fall through */
#endif
- goto restart_tracee_with_sig_0;
+ default:
+ goto restart_tracee_with_sig_0;
}
/*
}
if (sig != syscall_trap_sig) {
- siginfo_t si;
+ siginfo_t si = {};
/*
* True if tracee is stopped by signal
* TODO: shouldn't we check for errno == EINVAL too?
* We can get ESRCH instead, you know...
*/
- stopped = ptrace(PTRACE_GETSIGINFO, pid, 0, (long) &si) < 0;
+ stopped = ptrace(PTRACE_GETSIGINFO, pid, 0, &si) < 0;
#if USE_SEIZE
show_stopsig:
#endif
* This should be syscall entry or exit.
* Handle it.
*/
- if (trace_syscall(tcp) < 0) {
+ sig = 0;
+ if (trace_syscall(tcp, &sig) < 0) {
/*
* ptrace() failed in trace_syscall().
* Likely a result of process disappearing mid-flight.
*/
return true;
}
+ goto restart_tracee;
restart_tracee_with_sig_0:
sig = 0;
{
init(argc, argv);
+ exit_code = !nprocs;
+
while (trace())
;
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