1 files changed, 61 insertions, 0 deletions
diff --git a/xsslog.c b/xsslog.c
new file mode 100644
index 0000000..e6d7a63
--- /dev/null
+++ b/xsslog.c
@@ -0,0 +1,61 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#include "xsslog.h"
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static void StrAppend4(char target[], const char a[], const char b[],
+                       const char c[], const char d[]) {
+  stpcpy(stpcpy(stpcpy(stpcpy(target, a), b), c), d);
+}
+
+void CheckErrnoImpl(const bool condition, const char description[]) {
+  if (condition) {
+    return;
+  }
+  const int e = errno;
+  char buf[128];
+  fprintf(stderr, "%s: check %s failed: %s\n", kProjectName, description,
+          strerror_r(e, buf, 128));
+  _Exit(1);
+}
+
+void CheckRetImpl(const int e, const char description[]) {
+  if (e == 0) {
+    return;
+  }
+  char buf[128];
+  fprintf(stderr, "%s: %s failed: %s\n", kProjectName, description,
+          strerror_r(e, buf, 128));
+  _Exit(1);
+}
+
+void LogDebug(const char* const format, ...) {
+  const char colon_space[] = ": ";
+  char* const prefixed_format =
+      calloc(strlen(kProjectName) + strlen(colon_space) + strlen(format) + 2,
+             sizeof(char));
+  CHECK_ERRNO(prefixed_format != NULL);
+  StrAppend4(prefixed_format, kProjectName, ": ", format, "\n");
+  va_list args;
+  va_start(args, format);
+  vfprintf(stderr, prefixed_format, args);
+  va_end(args);
+  free(prefixed_format);
+}