Less ugly debug display of ptrace events

* strace.c (trace): Less ugly debug display of ptrace events.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/strace.c b/strace.c
index 4129a8a00f23deae421e9ebf01e1b482768659a1..4fdf723e45e71d2a9c355907d3328ea3e7fefe03 100644 (file)
--- a/strace.c
+++ b/strace.c
@@ -1816,24 +1816,7 @@ trace(void)
                event = ((unsigned)status >> 16);
                if (debug) {
                        char buf[sizeof("WIFEXITED,exitcode=%u") + sizeof(int)*3 /*paranoia:*/ + 16];
-                       if (event != 0) {
-                               static const char *const event_names[] = {
-                                       [PTRACE_EVENT_CLONE] = "CLONE",
-                                       [PTRACE_EVENT_FORK]  = "FORK",
-                                       [PTRACE_EVENT_VFORK] = "VFORK",
-                                       [PTRACE_EVENT_VFORK_DONE] = "VFORK_DONE",
-                                       [PTRACE_EVENT_EXEC]  = "EXEC",
-                                       [PTRACE_EVENT_EXIT]  = "EXIT",
-                               };
-                               const char *e;
-                               if (event < ARRAY_SIZE(event_names))
-                                       e = event_names[event];
-                               else {
-                                       sprintf(buf, "?? (%u)", event);
-                                       e = buf;
-                               }
-                               fprintf(stderr, " PTRACE_EVENT_%s", e);
-                       }
+                       char evbuf[sizeof(",PTRACE_EVENT_?? (%u)") + sizeof(int)*3 /*paranoia:*/ + 16];
                        strcpy(buf, "???");
                        if (WIFSIGNALED(status))
 #ifdef WCOREDUMP
@@ -1852,7 +1835,26 @@ trace(void)
                        if (WIFCONTINUED(status))
                                strcpy(buf, "WIFCONTINUED");
 #endif
-                       fprintf(stderr, " [wait(0x%04x) = %u] %s\n", status, pid, buf);
+                       evbuf[0] = '\0';
+                       if (event != 0) {
+                               static const char *const event_names[] = {
+                                       [PTRACE_EVENT_CLONE] = "CLONE",
+                                       [PTRACE_EVENT_FORK]  = "FORK",
+                                       [PTRACE_EVENT_VFORK] = "VFORK",
+                                       [PTRACE_EVENT_VFORK_DONE] = "VFORK_DONE",
+                                       [PTRACE_EVENT_EXEC]  = "EXEC",
+                                       [PTRACE_EVENT_EXIT]  = "EXIT",
+                               };
+                               const char *e;
+                               if (event < ARRAY_SIZE(event_names))
+                                       e = event_names[event];
+                               else {
+                                       sprintf(buf, "?? (%u)", event);
+                                       e = buf;
+                               }
+                               sprintf(evbuf, ",PTRACE_EVENT_%s", e);
+                       }
+                       fprintf(stderr, " [wait(0x%04x) = %u] %s%s\n", status, pid, buf, evbuf);
                }
 
                /* Look up 'pid' in our table. */