Move printpidfd from kcmp.c to util.c

And rename it to print_pid_fd in an attempt to minimise confusion with
the kernel's pidfd concept.

* kcmp (PRINT_FIELD_PIDFD, SYS_FUNC(kcmp)): Change printpidfd calls to
print_pid_fd.
(printpidfd): Move it...
* util.c (print_pid_fd): ...here. Drop the static qualifier, update
the comment describing why this is a stub.
* defs.h (print_pid_fd): New declaration.

3 files changed, 20 insertions, 14 deletions

diff --git a/defs.h b/defs.h
index 6e2d0f261..be1f0254e 100644
--- a/defs.h
+++ b/defs.h
@@ -1028,6 +1028,11 @@ printpath(struct tcb *, kernel_ulong_t addr);
 # define TIMESPEC_TEXT_BUFSIZE \
 		(sizeof(long long) * 3 * 2 + sizeof("{tv_sec=-, tv_nsec=}"))
 extern void printfd(struct tcb *, int);
+/**
+ * Print file descriptor fd owned by process with ID pid (from the PID NS
+ * of the tracee the descriptor tcp).  This is a stub.
+ */
+extern void print_pid_fd(struct tcb *tcp, pid_t pid, int fd);
 extern void print_sockaddr(const void *sa, int len);
 extern bool
 print_inet_addr(int af, const void *addr, unsigned int len, const char *var_name);
diff --git a/kcmp.c b/kcmp.c
index 6722d7742..2fc81dc63 100644
--- a/kcmp.c
+++ b/kcmp.c
@@ -16,20 +16,10 @@ struct strace_kcmp_epoll_slot {
 	uint32_t toff;
 };
 
-static void
-printpidfd(struct tcb *tcp, pid_t pid, int fd)
-{
-	/*
-	 * XXX We want to use printfd here, but we should figure out which
-	 *     process in strace's PID NS is referred to first.
-	 */
-	tprintf("%d", fd);
-}
-
 #define PRINT_FIELD_PIDFD(prefix_, where_, field_, tcp_, pid_)		\
 	do {								\
 		STRACE_PRINTF("%s%s=", (prefix_), #field_);		\
-		printpidfd((tcp_), (pid_), (where_).field_);		\
+		print_pid_fd((tcp_), (pid_), (where_).field_);		\
 	} while (0)
 
 SYS_FUNC(kcmp)
@@ -46,9 +36,9 @@ SYS_FUNC(kcmp)
 	switch (type) {
 		case KCMP_FILE:
 			tprints(", ");
-			printpidfd(tcp, pid1, idx1);
+			print_pid_fd(tcp, pid1, idx1);
 			tprints(", ");
-			printpidfd(tcp, pid1, idx2);
+			print_pid_fd(tcp, pid1, idx2);
 
 			break;
 
@@ -56,7 +46,7 @@ SYS_FUNC(kcmp)
 			struct strace_kcmp_epoll_slot slot;
 
 			tprints(", ");
-			printpidfd(tcp, pid1, idx1);
+			print_pid_fd(tcp, pid1, idx1);
 			tprints(", ");
 
 			if (umove_or_printaddr(tcp, idx2, &slot))
diff --git a/util.c b/util.c
index 1cb767d05..a76865304 100644
--- a/util.c
+++ b/util.c
@@ -590,6 +590,17 @@ printed:
 	}
 }
 
+void
+print_pid_fd(struct tcb *tcp, pid_t pid, int fd)
+{
+	/*
+	 * TODO: We want to have the same formatting as printfd here,
+	 *       but we should figure out first which process in strace's
+	 *       PID NS is referred to by pid in tracee's PID NS.
+	 */
+	tprintf("%d", fd);
+}
+
 /*
  * Quote string `instr' of length `size'
  * Write up to (3 + `size' * 4) bytes to `outstr' buffer.