Create linker_log[_va_list] functions

A later linker CL defines a function that needs to forward a printf format
and argument list to TRACE(), but there is no version of the TRACE macro
that works with a va_list. The CL also needs to check the verbosity level,
using a slow path if tracing is enabled, so define LINKER_VERBOSITY_xxx
macros.

Bug: none
Test: bionic unit tests
Change-Id: I578d36a12dc40f9a651956b4b09adc1a7c644e24

1 files changed, 47 insertions, 0 deletions

diff --git a/linker/linker_debug.cpp b/linker/linker_debug.cpp
new file mode 100644
index 000000000..b0aae79b9
--- /dev/null
+++ b/linker/linker_debug.cpp
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "linker_debug.h"
+
+#include <unistd.h>
+
+void linker_log_va_list(int prio __unused, const char* fmt, va_list ap) {
+#if LINKER_DEBUG_TO_LOG
+  async_safe_format_log_va_list(5 - prio, "linker", fmt, ap);
+#else
+  async_safe_format_fd_va_list(STDOUT_FILENO, fmt, ap);
+  write(STDOUT_FILENO, "\n", 1);
+#endif
+}
+
+void linker_log(int prio, const char* fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  linker_log_va_list(prio, fmt, ap);
+  va_end(ap);
+}