Fix PID prefix printing in "strace -oLOG -ff -p1 -p2 -p3" case

In this case we were printing PIDs to LOG.* files
even though it is not necessary.

The fix is in the addition of "&& followfork < 2" condition.

* strace.c: Remove pflag_seen variable, add print_pid_pfx one.
(process_opt_p_list): Do not pflag_seen++.
(main): Use "nprocs != 0" condition instead of "pflag_seen != 0".
Set print_pid_pfx before entering main tracing loop.
(printleader): Use print_pid_pfx to decide whether to print pid prefix.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2012-03-09 13:03:41 +01:00
parent e8172b79e3
commit fd88338067

View File

@ -72,7 +72,8 @@ unsigned int ptrace_setoptions = 0;
static unsigned int syscall_trap_sig = SIGTRAP;
int dtime = 0, xflag = 0, qflag = 0;
cflag_t cflag = CFLAG_NONE;
static int iflag = 0, pflag_seen = 0, rflag = 0, tflag = 0;
static int iflag = 0, rflag = 0, tflag = 0;
static int print_pid_pfx = 0;
/* -I n */
enum {
@ -447,12 +448,6 @@ static void process_opt_p_list(char *opt)
*delim = c;
tcp = alloc_tcb(pid, 0);
tcp->flags |= TCB_ATTACHED;
/*
* pflag_seen says how many PIDs we handled,
* not how many -p opts there were.
* Used to decide whether to print pid prefix in logs.
*/
pflag_seen++;
if (c == '\0')
break;
opt = delim + 1;
@ -1210,10 +1205,10 @@ main(int argc, char *argv[])
acolumn_spaces[acolumn] = '\0';
/* Must have PROG [ARGS], or -p PID. Not both. */
if (!argv[0] == !pflag_seen)
if (!argv[0] == !nprocs)
usage(stderr, 1);
if (pflag_seen && daemonized_tracer) {
if (nprocs != 0 && daemonized_tracer) {
error_msg_and_die("-D and -p are mutually exclusive options");
}
@ -1331,9 +1326,16 @@ main(int argc, char *argv[])
sa.sa_handler = SIG_DFL;
sigaction(SIGCHLD, &sa, NULL);
if (pflag_seen || daemonized_tracer)
if (nprocs != 0 || daemonized_tracer)
startup_attach();
/* Do we want pids printed in our -o OUTFILE?
* -ff: no (every pid has its own file); or
* -f: yes (there can be more pids in the future); or
* -p PID1,PID2: yes (there are already more than one pid)
*/
print_pid_pfx = (outfname && followfork < 2 && (followfork == 1 || nprocs > 1));
if (trace() < 0)
exit(1);
@ -2094,10 +2096,12 @@ printleader(struct tcb *tcp)
printing_tcp = tcp;
curcol = 0;
if ((followfork == 1 || pflag_seen > 1) && outfname)
if (print_pid_pfx)
tprintf("%-5d ", tcp->pid);
else if (nprocs > 1 && !outfname)
tprintf("[pid %5u] ", tcp->pid);
if (tflag) {
char str[sizeof("HH:MM:SS")];
struct timeval tv, dtv;