xref: /aosp_15_r20/external/cronet/base/process/environment_internal.h (revision 6777b5387eb2ff775bb5750e3f5d96f37fb7352b)
1 // Copyright 2019 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 // This file contains internal routines that are called by other files in
6 // base/process/.
7 
8 #ifndef BASE_PROCESS_ENVIRONMENT_INTERNAL_H_
9 #define BASE_PROCESS_ENVIRONMENT_INTERNAL_H_
10 
11 #include <memory>
12 
13 #include "base/base_export.h"
14 #include "base/environment.h"
15 #include "build/build_config.h"
16 
17 namespace base {
18 namespace internal {
19 
20 #if BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA)
21 // Returns a modified environment vector constructed from the given environment
22 // and the list of changes given in |changes|. Each key in the environment is
23 // matched against the first element of the pairs. In the event of a match, the
24 // value is replaced by the second of the pair, unless the second is empty, in
25 // which case the key-value is removed.
26 //
27 // This POSIX version takes and returns a POSIX-style environment block, which
28 // is a null-terminated list of pointers to null-terminated strings. The
29 // returned array will have appended to it the storage for the array itself so
30 // there is only one pointer to manage, but this means that you can't copy the
31 // array without keeping the original around.
32 BASE_EXPORT std::unique_ptr<char*[]> AlterEnvironment(
33     const char* const* env,
34     const EnvironmentMap& changes);
35 #elif BUILDFLAG(IS_WIN)
36 // Returns a modified environment vector constructed from the given environment
37 // and the list of changes given in |changes|. Each key in the environment is
38 // matched against the first element of the pairs. In the event of a match, the
39 // value is replaced by the second of the pair, unless the second is empty, in
40 // which case the key-value is removed.
41 //
42 // This Windows version takes and returns a Windows-style environment block,
43 // which is a string containing several null-terminated strings followed by an
44 // extra terminating null character. So, e.g., the environment A=1 B=2 is
45 // represented as L"A=1\0B=2\0\0".
46 BASE_EXPORT NativeEnvironmentString
47 AlterEnvironment(const wchar_t* env, const EnvironmentMap& changes);
48 #endif  // OS_*
49 
50 }  // namespace internal
51 }  // namespace base
52 
53 #endif  // BASE_PROCESS_ENVIRONMENT_INTERNAL_H_
54