From: Willy Tarreau <w@1wt.eu>
Date: Mon, 10 Aug 2026 16:28:38 +0000 (+0200)
Subject: MINOR: debug: make the complain() function start to complete the message
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=53ed9fe86ba42abb275bac8008791303e809fe2b;p=thirdparty%2Fhaproxy.git

MINOR: debug: make the complain() function start to complete the message

The function will be extended to automatically prepend/append some info.
For now all it does is to always prepend/append the "\n" that each message
has at the beggining and at the end.

We're doing this into a locally allocated iovec and emit it at once using
writev(). This will be easy to extend to pass extra info. The \n alone
removed 1.5 kB of code.
---

diff --git a/include/haproxy/bug.h b/include/haproxy/bug.h
index 5b408db23..20e9ae758 100644
--- a/include/haproxy/bug.h
+++ b/include/haproxy/bug.h
@@ -301,7 +301,7 @@ static __attribute__((noinline,noreturn,unused)) void abort_with_line(uint line)
 
 #define __ABORT_NOW(file, line, ...) do {				\
 		if (sizeof("" __VA_ARGS__) > 1)				\
-			complain(DBG_FATL_ABT, "\nABORT at " file ":" #line ": " __VA_ARGS__ "\n"); \
+			complain(DBG_FATL_ABT, "ABORT at " file ":" #line ": " __VA_ARGS__); \
 		ha_backtrace_to_stderr(1);				\
 		abort_with_line(__LINE__);				\
 	} while (0)
@@ -411,9 +411,9 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
 #define __BUG_ON(cond, file, line, details, pfx, sfx, ...) do {		\
 		const char *msg;					\
 		if (sizeof("" __VA_ARGS__) > 1)				\
-			msg ="\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n" __VA_ARGS__ "\n"; \
+			msg = pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n" __VA_ARGS__; \
 		else							\
-			msg = "\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n"; \
+			msg = pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx; \
 		complain(details, msg);					\
 		if (details & DBG_DET_FAT_FATL)				\
 			ABORT_NOW();					\
@@ -437,9 +437,9 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
 		static int __match_count_##line;			\
 		const char *msg;					\
 		if (sizeof("" __VA_ARGS__) > 1)				\
-			msg ="\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n" __VA_ARGS__ "\n"; \
+			msg = pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n" __VA_ARGS__; \
 		else							\
-			msg = "\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n"; \
+			msg = pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx; \
 		if (_HA_ATOMIC_FETCH_ADD(&__match_count_##line, 1))	\
 			break;						\
 		complain(details, msg);					\
diff --git a/src/debug.c b/src/debug.c
index 9c029837a..42f65af6e 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -21,6 +21,7 @@
 #include <sys/resource.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#include <sys/uio.h>
 #include <sys/utsname.h>
 #include <sys/wait.h>
 #include <unistd.h>
@@ -964,13 +965,30 @@ void ha_stuck_warning(void)
 	DISGUISE(write(2, buf.area, buf.data));
 }
 
-/* Complain with message <msg> on stderr. <details> is only
- * checked on DBG_DET_TYP_BUG, and will taint the process either for a
- * bug or warn.
+/* Complain with message <msg> on stderr with a '\n' at the begin and at the
+ * end. Depending on the fatality, and type of the event in <details>, a
+ * different prefix will be appended. Then the event type may result in some
+ * taining of the process to happen.
  */
 void complain(uint details, const char *msg)
 {
-	DISGUISE(write(2, msg, strlen(msg)));
+	struct iovec iovec[10];
+	int vec = 0;
+
+	iovec[vec].iov_base = "\n";
+	iovec[vec].iov_len  = 1;
+	vec++;
+
+	iovec[vec].iov_base = (char *)msg;
+	iovec[vec].iov_len  = strlen(msg);
+	vec++;
+
+	iovec[vec].iov_base = "\n";
+	iovec[vec].iov_len  = 1;
+	vec++;
+
+	DISGUISE(writev(2, iovec, vec));
+
 	if (details & (DBG_DET_TYP_BUG|DBG_DET_TYP_ABT))
 		mark_tainted(TAINTED_BUG);
 	else if (details & DBG_DET_TYP_WRN)