/*
- * Copyright 2013 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* limitations under the License.
*/
-#ifndef FOLLY_EXCEPTION_H_
-#define FOLLY_EXCEPTION_H_
+#pragma once
#include <errno.h>
+#include <cstdio>
#include <stdexcept>
#include <system_error>
-#include "folly/Likely.h"
+#include <folly/Conv.h>
+#include <folly/FBString.h>
+#include <folly/Likely.h>
+#include <folly/Portability.h>
namespace folly {
+// Various helpers to throw appropriate std::system_error exceptions from C
+// library errors (returned in errno, as positive return values (many POSIX
+// functions), or as negative return values (Linux syscalls))
+//
+// The *Explicit functions take an explicit value for errno.
+
// Helper to throw std::system_error
-void throwSystemError(int err, const char* msg) __attribute__((noreturn));
-inline void throwSystemError(int err, const char* msg) {
+[[noreturn]] inline void throwSystemErrorExplicit(int err, const char* msg) {
throw std::system_error(err, std::system_category(), msg);
}
-// Helper to throw std::system_error from errno
-void throwSystemError(const char* msg) __attribute__((noreturn));
-inline void throwSystemError(const char* msg) {
- throwSystemError(errno, msg);
+template <class... Args>
+[[noreturn]] void throwSystemErrorExplicit(int err, Args&&... args) {
+ throwSystemErrorExplicit(
+ err, to<fbstring>(std::forward<Args>(args)...).c_str());
+}
+
+// Helper to throw std::system_error from errno and components of a string
+template <class... Args>
+[[noreturn]] void throwSystemError(Args&&... args) {
+ throwSystemErrorExplicit(errno, std::forward<Args>(args)...);
}
// Check a Posix return code (0 on success, error number on error), throw
// on error.
-inline void checkPosixError(int err, const char* msg) {
+template <class... Args>
+void checkPosixError(int err, Args&&... args) {
if (UNLIKELY(err != 0)) {
- throwSystemError(err, msg);
+ throwSystemErrorExplicit(err, std::forward<Args>(args)...);
}
}
// Check a Linux kernel-style return code (>= 0 on success, negative error
// number on error), throw on error.
-inline void checkKernelError(ssize_t ret, const char* msg) {
+template <class... Args>
+void checkKernelError(ssize_t ret, Args&&... args) {
if (UNLIKELY(ret < 0)) {
- throwSystemError(-ret, msg);
+ throwSystemErrorExplicit(int(-ret), std::forward<Args>(args)...);
}
}
-// Check a traditional Uinx return code (-1 and sets errno on error), throw
+// Check a traditional Unix return code (-1 and sets errno on error), throw
// on error.
-inline void checkUnixError(ssize_t ret, const char* msg) {
+template <class... Args>
+void checkUnixError(ssize_t ret, Args&&... args) {
if (UNLIKELY(ret == -1)) {
- throwSystemError(msg);
+ throwSystemError(std::forward<Args>(args)...);
}
}
-inline void checkUnixError(ssize_t ret, int savedErrno, const char* msg) {
+
+template <class... Args>
+void checkUnixErrorExplicit(ssize_t ret, int savedErrno, Args&&... args) {
if (UNLIKELY(ret == -1)) {
- throwSystemError(savedErrno, msg);
+ throwSystemErrorExplicit(savedErrno, std::forward<Args>(args)...);
+ }
+}
+
+// Check the return code from a fopen-style function (returns a non-nullptr
+// FILE* on success, nullptr on error, sets errno). Works with fopen, fdopen,
+// freopen, tmpfile, etc.
+template <class... Args>
+void checkFopenError(FILE* fp, Args&&... args) {
+ if (UNLIKELY(!fp)) {
+ throwSystemError(std::forward<Args>(args)...);
}
}
-} // namespace folly
+template <class... Args>
+void checkFopenErrorExplicit(FILE* fp, int savedErrno, Args&&... args) {
+ if (UNLIKELY(!fp)) {
+ throwSystemErrorExplicit(savedErrno, std::forward<Args>(args)...);
+ }
+}
-#endif /* FOLLY_EXCEPTION_H_ */
+/**
+ * If cond is not true, raise an exception of type E. E must have a ctor that
+ * works with const char* (a description of the failure).
+ */
+#define CHECK_THROW(cond, E) \
+ do { \
+ if (!(cond)) { \
+ throw E("Check failed: " #cond); \
+ } \
+ } while (0)
+} // namespace folly