Hide startup syscalls.

Tested with "./strace [-D] [-q] [-bexecve] env true",
all cases seem to work.

* defs.h: Declare new variable: bool hide_log_until_execve.
* strace.c: Define hide_log_until_execve.
Rename skip_startup_execve to skip_one_b_execve.
(startup_child): Do not set skip_one_b_execve = 1 here.
(init): If "strace PROG" case (as opposed to "strace -pPID"),
set skip_one_b_execve and hide_log_until_execve to 1.
(trace): Don't print signal messages if hide_log_until_execve == 1.
* syscall.c (trace_syscall_entering):
Skip syscall printing if hide_log_until_execve == 1.
Reset hide_log_until_execve if we enter execve syscall.
(trace_syscall_exiting): Skip syscall printing if hide_log_until_execve == 1.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/syscall.c b/syscall.c
index 833dacd..7efee0e 100644
--- a/syscall.c
+++ b/syscall.c
@@ -1985,6 +1985,14 @@ trace_syscall_entering(struct tcb *tcp)
 		goto ret;
 	}
 
+	if (   sys_execve == tcp->s_ent->sys_func
+# if defined(SPARC) || defined(SPARC64)
+	    || sys_execv == tcp->s_ent->sys_func
+# endif
+	   ) {
+		hide_log_until_execve = 0;
+	}
+
 #if defined(SYS_socket_subcall) || defined(SYS_ipc_subcall)
 	while (1) {
 # ifdef SYS_socket_subcall
@@ -2015,7 +2023,7 @@ trace_syscall_entering(struct tcb *tcp)
 
 	tcp->flags &= ~TCB_FILTERED;
 
-	if (cflag == CFLAG_ONLY_STATS) {
+	if (cflag == CFLAG_ONLY_STATS || hide_log_until_execve) {
 		res = 0;
 		goto ret;
 	}
@@ -2503,7 +2511,7 @@ trace_syscall_exiting(struct tcb *tcp)
 		get_error(tcp); /* never fails */
 		if (need_fork_exec_workarounds)
 			syscall_fixup_for_fork_exec(tcp);
-		if (filtered(tcp))
+		if (filtered(tcp) || hide_log_until_execve)
 			goto ret;
 	}