From f9797c91e190fc53ce997beb1e7c2a140abfd665 Mon Sep 17 00:00:00 2001
From: Peter Jones <pjones@redhat.com>
Date: Tue, 15 Oct 2019 16:27:39 -0400
Subject: [PATCH 51/63] debug(): don't write newlines to memfd

If we know our log will only be seen by strace, the newlines don't add
anything to the strings but clutter.

Signed-off-by: Peter Jones <pjones@redhat.com>
---
 src/error.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/error.c b/src/error.c
index 083de15e984..8ceba31dd55 100644
--- a/src/error.c
+++ b/src/error.c
@@ -27,6 +27,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <sys/mman.h>
+#include <sys/random.h>
 #include <unistd.h>
 
 #include "efiboot.h"
@@ -166,6 +167,7 @@ efi_error_pop(void)
 static int efi_verbose;
 static FILE *efi_errlog, *efi_dbglog;
 static int efi_dbglog_fd = -1;
+static intptr_t efi_dbglog_cookie;
 static int log_level;
 static char efi_dbglog_buf[4096];
 
@@ -176,7 +178,7 @@ efi_set_loglevel(int level)
 }
 
 static ssize_t
-dbglog_write(void *cookie UNUSED, const char *buf, size_t size)
+dbglog_write(void *cookie, const char *buf, size_t size)
 {
 	FILE *log = efi_errlog ? efi_errlog : stderr;
 	ssize_t ret = size;
@@ -185,6 +187,11 @@ dbglog_write(void *cookie UNUSED, const char *buf, size_t size)
 		ret = fwrite(buf, 1, size, log);
 	} else if (efi_dbglog_fd >= 0) {
 		lseek(efi_dbglog_fd, 0, SEEK_SET);
+		if ((intptr_t)cookie != 0 &&
+		    (intptr_t)cookie == efi_dbglog_cookie &&
+		    size > 0 &&
+		    buf[size-1] == '\n')
+			size -= 1;
 		ret = write(efi_dbglog_fd, buf, size);
 	}
 	return ret;
@@ -248,6 +255,7 @@ efi_error_fini(void)
 static void CONSTRUCTOR
 efi_error_init(void)
 {
+	ssize_t bytes;
 	cookie_io_functions_t io_funcs = {
 		.write = dbglog_write,
 		.seek = dbglog_seek,
@@ -258,7 +266,11 @@ efi_error_init(void)
 	if (efi_dbglog_fd == -1)
 		return;
 
-	efi_dbglog = fopencookie(NULL, "a", io_funcs);
+	bytes = getrandom(&efi_dbglog_cookie, sizeof(efi_dbglog_cookie), 0);
+	if (bytes < (ssize_t)sizeof(efi_dbglog_cookie))
+		efi_dbglog_cookie = 0;
+
+	efi_dbglog = fopencookie((void *)efi_dbglog_cookie, "a", io_funcs);
 	if (efi_dbglog)
 		setvbuf(efi_dbglog, efi_dbglog_buf, _IOLBF,
 			sizeof(efi_dbglog_buf));
-- 
2.26.2