From 8806a21b612d76c8732d0df2ebaf52b62166ce51 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?=C3=81kos=20Uzonyi?= <uzonyi.akos@gmail.com>

Date: Sat, 13 Jun 2020 18:18:31 +0200

Subject: [PATCH 119/138] print_fields.h: add PRINT_FIELD_LEN macro

* print_fields.h (PRINT_FIELD_LEN): New macro.

* net.c: (print_get_linger, print_get_ucred, print_tpacket_stats):

Rewrite using PRINT_FIELD_LEN.

---

 net.c          | 90 ++++++----------------------------------------------------

 print_fields.h | 15 ++++++++++

 2 files changed, 23 insertions(+), 82 deletions(-)

diff --git a/net.c b/net.c

index a58fa92..9ea34b2 100644

--- a/net.c

+++ b/net.c

@@ -579,24 +579,8 @@ print_get_linger(struct tcb *const tcp, const kernel_ulong_t addr,

 	if (umoven_or_printaddr(tcp, addr, len, &linger))

 		return;

-	if (len < sizeof(linger.l_onoff)) {

-		tprints("{l_onoff=");

-		print_quoted_string((void *) &linger.l_onoff,

-				    len, QUOTE_FORCE_HEX);

-	} else {

-		PRINT_FIELD_D("{", linger, l_onoff);

-

-		if (len > offsetof(struct linger, l_linger)) {

-			len -= offsetof(struct linger, l_linger);

-			if (len < sizeof(linger.l_linger)) {

-				tprints(", l_linger=");

-				print_quoted_string((void *) &linger.l_linger,

-						    len, QUOTE_FORCE_HEX);

-			} else {

-				PRINT_FIELD_D(", ", linger, l_linger);

-			}

-		}

-	}

+	PRINT_FIELD_LEN("{", linger, l_onoff, len, PRINT_FIELD_D);

+	PRINT_FIELD_LEN(", ", linger, l_linger, len, PRINT_FIELD_D);

 	tprints("}");

 }

@@ -617,38 +601,9 @@ print_get_ucred(struct tcb *const tcp, const kernel_ulong_t addr,

 	if (umoven_or_printaddr(tcp, addr, len, &uc))

 		return;

-	if (len < sizeof(uc.pid)) {

-		tprints("{pid=");

-		print_quoted_string((void *) &uc.pid,

-				    len, QUOTE_FORCE_HEX);

-	} else {

-		PRINT_FIELD_D("{", uc, pid);

-

-		if (len > offsetof(struct ucred, uid)) {

-			len -= offsetof(struct ucred, uid);

-			if (len < sizeof(uc.uid)) {

-				tprints(", uid=");

-				print_quoted_string((void *) &uc.uid,

-						    len, QUOTE_FORCE_HEX);

-			} else {

-				PRINT_FIELD_UID(", ", uc, uid);

-

-				if (len > offsetof(struct ucred, gid) -

-					  offsetof(struct ucred, uid)) {

-					len -= offsetof(struct ucred, gid) -

-					       offsetof(struct ucred, uid);

-					if (len < sizeof(uc.gid)) {

-						tprints(", gid=");

-						print_quoted_string((void *) &uc.gid,

-								    len,

-								    QUOTE_FORCE_HEX);

-					} else {

-						PRINT_FIELD_UID(", ", uc, gid);

-					}

-				}

-			}

-		}

-	}

+	PRINT_FIELD_LEN("{", uc, pid, len, PRINT_FIELD_D);

+	PRINT_FIELD_LEN(", ", uc, uid, len, PRINT_FIELD_UID);

+	PRINT_FIELD_LEN(", ", uc, gid, len, PRINT_FIELD_UID);

 	tprints("}");

 }

@@ -688,38 +643,9 @@ print_tpacket_stats(struct tcb *const tcp, const kernel_ulong_t addr,

 	if (umoven_or_printaddr(tcp, addr, len, &stats))

 		return;

-	if (len < sizeof(stats.tp_packets)) {

-		tprints("{tp_packets=");

-		print_quoted_string((void *) &stats.tp_packets,

-				    len, QUOTE_FORCE_HEX);

-	} else {

-		PRINT_FIELD_U("{", stats, tp_packets);

-

-		if (len > offsetof(struct tp_stats, tp_drops)) {

-			len -= offsetof(struct tp_stats, tp_drops);

-			if (len < sizeof(stats.tp_drops)) {

-				tprints(", tp_drops=");

-				print_quoted_string((void *) &stats.tp_drops,

-						    len, QUOTE_FORCE_HEX);

-			} else {

-				PRINT_FIELD_U(", ", stats, tp_drops);

-

-				if (len > offsetof(struct tp_stats, tp_freeze_q_cnt) -

-					  offsetof(struct tp_stats, tp_drops)) {

-					len -= offsetof(struct tp_stats, tp_freeze_q_cnt) -

-					       offsetof(struct tp_stats, tp_drops);

-					if (len < sizeof(stats.tp_freeze_q_cnt)) {

-						tprints(", tp_freeze_q_cnt=");

-						print_quoted_string((void *) &stats.tp_freeze_q_cnt,

-								    len,

-								    QUOTE_FORCE_HEX);

-					} else {

-						PRINT_FIELD_U(", ", stats, tp_freeze_q_cnt);

-					}

-				}

-			}

-		}

-	}

+	PRINT_FIELD_LEN("{", stats, tp_packets, len, PRINT_FIELD_U);

+	PRINT_FIELD_LEN(", ", stats, tp_drops, len, PRINT_FIELD_U);

+	PRINT_FIELD_LEN(", ", stats, tp_freeze_q_cnt, len, PRINT_FIELD_U);

 	tprints("}");

 }

 #endif /* PACKET_STATISTICS */

diff --git a/print_fields.h b/print_fields.h

index 02c56bf..70dbbff 100644

--- a/print_fields.h

+++ b/print_fields.h

@@ -277,4 +277,19 @@

 			       (size_), (hwtype_));			\

 	} while (0)

+# define PRINT_FIELD_LEN(prefix_, where_, field_, 			\

+			len_, print_func_, ...)				\

+	do {								\

+		unsigned int start = offsetof(typeof(where_), field_);	\

+		unsigned int end = start + sizeof(where_.field_);	\

+		if (len_ >= end) {					\

+			print_func_(prefix_, where_, field_,		\

+					##__VA_ARGS__);			\

+		} else if (len_ > start) {				\

+			tprintf("%s%s=", prefix_, #field_);		\

+			print_quoted_string((void *)&where_.field_,	\

+					len_ - start, QUOTE_FORCE_HEX);	\

+		}							\

+	} while (0)

+

 #endif /* !STRACE_PRINT_FIELDS_H */

-- 

2.1.4