Fix copyright lines

[folly.git] / folly / portability / Stdlib.cpp

diff --git a/folly/portability/Stdlib.cpp b/folly/portability/Stdlib.cpp
index 85cbe0b042523264be8fb57fc038fdae0e50f30c..7b78c3da75dab571fe60d2bba1285466181d49f5 100644 (file)
--- a/folly/portability/Stdlib.cpp
+++ b/folly/portability/Stdlib.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2016-present Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,7 +17,9 @@
 #include <folly/portability/Stdlib.h>
 
 #ifdef _WIN32
+
 #include <cstring>
+
 #include <errno.h>
 
 #include <folly/portability/Fcntl.h>
@@ -25,7 +27,9 @@
 #include <folly/portability/Windows.h>
 
 extern "C" {
-char* mktemp(char* tn) { return _mktemp(tn); }
+char* mktemp(char* tn) {
+  return _mktemp(tn);
+}
 
 // While yes, this is for a directory, due to this being windows,
 // a file and directory can't have the same name, resulting in this
@@ -70,5 +74,99 @@ char* realpath(const char* path, char* resolved_path) {
   // I sure hope the caller gave us _MAX_PATH space in the buffer....
   return _fullpath(resolved_path, path, _MAX_PATH);
 }
+
+int setenv(const char* name, const char* value, int overwrite) {
+  if (overwrite == 0 && getenv(name) != nullptr) {
+    return 0;
+  }
+
+  if (*value != '\0') {
+    auto e = _putenv_s(name, value);
+    if (e != 0) {
+      errno = e;
+      return -1;
+    }
+    return 0;
+  }
+
+  // We are trying to set the value to an empty string, but
+  // _putenv_s deletes entries if the value is an empty string,
+  // and just calling SetEnvironmentVariableA doesn't update
+  // _environ, so we have to do these terrible things.
+  if (_putenv_s(name, "  ") != 0) {
+    errno = EINVAL;
+    return -1;
+  }
+
+  // Here lies the documentation we blatently ignore to make
+  // this work >_>...
+  *getenv(name) = '\0';
+  // This would result in a double null termination, which
+  // normally signifies the end of the environment variable
+  // list, so we stick a completely empty environment variable
+  // into the list instead.
+  *(getenv(name) + 1) = '=';
+
+  // If _wenviron is null, the wide environment has not been initialized
+  // yet, and we don't need to try to update it.
+  // We have to do this otherwise we'd be forcing the initialization and
+  // maintenance of the wide environment even though it's never actually
+  // used in most programs.
+  if (_wenviron != nullptr) {
+    wchar_t buf[_MAX_ENV + 1];
+    size_t len;
+    if (mbstowcs_s(&len, buf, _MAX_ENV + 1, name, _MAX_ENV) != 0) {
+      errno = EINVAL;
+      return -1;
+    }
+    *_wgetenv(buf) = u'\0';
+    *(_wgetenv(buf) + 1) = u'=';
+  }
+
+  // And now, we have to update the outer environment to have
+  // a proper empty value.
+  if (!SetEnvironmentVariableA(name, value)) {
+    errno = EINVAL;
+    return -1;
+  }
+  return 0;
 }
+
+int unsetenv(const char* name) {
+  if (_putenv_s(name, "") != 0) {
+    return -1;
+  }
+  return 0;
+}
+}
+
+#endif
+
+#if !__linux__ && !FOLLY_MOBILE
+
+#include <string>
+#include <vector>
+
+extern "C" int clearenv() {
+  std::vector<std::string> data;
+  for (auto it = environ; it && *it; ++it) {
+    std::string entry(*it);
+    auto equalsPosition = entry.find('=');
+    if (equalsPosition == std::string::npos || equalsPosition == 0) {
+      // It's either a drive setting (if on Windows), or something clowny is
+      // going on in the environment.
+      continue;
+    } else {
+      data.emplace_back(entry.substr(0, equalsPosition));
+    }
+  }
+
+  for (auto s : data) {
+    if (unsetenv(s.c_str()) != 0)
+      return -1;
+  }
+
+  return 0;
+}
+
 #endif