libsandbox: avoid mixing stderr & output pipes

The various debug helpers were changed to write out to a dedicated message
path, but some of the trace code still uses stderr directly.  When mixing
these methods, the direct prints would sometimes be lost.  Convert the few
users to a new raw print function so they all route through the same file.

We might want to extract this a bit more out in the future so it's easier
to write to them, but this should be fine for now.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

4 files changed, 18 insertions, 5 deletions

diff --git a/libsandbox/trace.c b/libsandbox/trace.c
index d424389..5ccda2a 100644
--- a/libsandbox/trace.c
+++ b/libsandbox/trace.c
@@ -18,7 +18,7 @@ static long _do_ptrace(enum __ptrace_request request, const char *srequest, void
 #else
 # define SBDEBUG 0
 #endif
-#define __sb_debug(fmt, args...) do { if (SBDEBUG) sb_printf(fmt, ## args); } while (0)
+#define __sb_debug(fmt, args...) do { if (SBDEBUG) sb_eraw(fmt, ## args); } while (0)
 #define _sb_debug(fmt, args...)  do { if (SBDEBUG) sb_ewarn("TRACE (pid=%i):%s: " fmt, getpid(), __func__, ## args); } while (0)
 #define sb_debug(fmt, args...)   _sb_debug(fmt "\n", ## args)
 
diff --git a/libsandbox/trace/linux/x86_64.c b/libsandbox/trace/linux/x86_64.c
index 82c492d..aff1edb 100644
--- a/libsandbox/trace/linux/x86_64.c
+++ b/libsandbox/trace/linux/x86_64.c
@@ -129,8 +129,8 @@ static unsigned long trace_arg(void *vregs, int num)
 static void trace_dump_regs(void *vregs)
 {
 	trace_regs *regs = vregs;
-	sb_printf("{ ");
-#define D(r) sb_printf(#r":%"PRIu64" ", regs->r)
+	__sb_debug("{ ");
+#define D(r) __sb_debug(#r":%"PRIu64" ", regs->r)
 	D(rax);
 	D(rdi);
 	D(rsi);
@@ -139,6 +139,6 @@ static void trace_dump_regs(void *vregs)
 	D(r8);
 	D(r9);
 #undef D
-	sb_printf("}");
+	__sb_debug("}");
 }
 #endif
diff --git a/libsbutil/sb_efuncs.c b/libsbutil/sb_efuncs.c
index 2de3116..7ded90d 100644
--- a/libsbutil/sb_efuncs.c
+++ b/libsbutil/sb_efuncs.c
@@ -48,7 +48,8 @@ static void sb_vefunc(const char *prog, const char *color, const char *format, v
 	if (fd == -1)
 		fd = fileno(stderr);
 
-	sb_fdprintf(fd, " %s*%s ", color, COLOR_NORMAL);
+	if (color)
+		sb_fdprintf(fd, " %s*%s ", color, COLOR_NORMAL);
 	sb_vfdprintf(fd, format, args);
 
 	if (opened)
@@ -98,6 +99,17 @@ void sb_eqawarn(const char *format, ...)
 	va_end(args);
 }
 
+/* This is a bit of a hack to expose the same file logic to generic printers.
+ * Probably want to revisit sb_vefunc and move the guts there to a new func.
+ */
+void sb_eraw(const char *format, ...)
+{
+	va_list args;
+	va_start(args, format);
+	sb_vefunc(NULL, NULL, format, args);
+	va_end(args);
+}
+
 void sb_dump_backtrace(void)
 {
 #ifdef HAVE_BACKTRACE
diff --git a/libsbutil/sbutil.h b/libsbutil/sbutil.h
index 15979da..66c6f73 100644
--- a/libsbutil/sbutil.h
+++ b/libsbutil/sbutil.h
@@ -112,6 +112,7 @@ __printf(1, 2) void sb_ewarn(const char *format, ...);
 __printf(1, 2) void sb_eerror(const char *format, ...);
 __printf(1, 2) void sb_eqawarn(const char *format, ...);
 __printf(1, 2) void sb_debug_dyn(const char *format, ...);
+__printf(1, 2) void sb_eraw(const char *format, ...);
 __printf(4, 5) void __sb_ebort(const char *file, const char *func, size_t line_num, const char *format, ...) __noreturn;
 #define sb_ebort(format, ...) __sb_ebort(__FILE__, __func__, __LINE__, format, ## __VA_ARGS__)
 void sb_dump_backtrace(void);