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Reactos
1/***
2*wincmdln.c - process command line for WinMain
3*
4* Copyright (c) Microsoft Corporation. All rights reserved.
5*
6*Purpose:
7* Prepare command line to be passed to [w]WinMain.
8*
9*******************************************************************************/
10
11#include <corecrt_internal.h>
12#include <mbstring.h>
13
14
15
16// In the function below, we need to ensure that we've initialized the mbc table
17// before we start performing character transformations.
18static void do_locale_initialization(unsigned char) throw() { __acrt_initialize_multibyte(); }
19static void do_locale_initialization(wchar_t) throw() { /* no-op */ }
20
21static unsigned char* get_command_line(unsigned char) throw()
22{
23 return reinterpret_cast<unsigned char *>(_acmdln);
24}
25
26static wchar_t* get_command_line(wchar_t) throw() { return _wcmdln; }
27
28
29// should_copy_another_character is *ONLY* checking for DBCS lead bytes to see if there
30// might be a following trail byte. This works because the callers are only concerned
31// about escaped quote sequences and other codepages aren't using those quotes.
32static bool __cdecl should_copy_another_character(unsigned char const c) throw()
33{
34 // This is OK for UTF-8 as a quote is never a trail byte.
35 return _ismbblead(c) != 0;
36}
37
38static bool __cdecl should_copy_another_character(wchar_t) throw()
39{
40 // This is OK for UTF-16 as a quote is never part of a surrogate pair.
41 return false;
42}
43
44
45
46/***
47*_[w]wincmdln
48*
49*Purpose:
50* Extract the command line tail to be passed to WinMain.
51*
52* Be warned! This code was originally implemented by the NT group and
53* has remained pretty much unchanged since 12-91. It should be changed
54* only with extreme care since there are undoubtedly many apps which
55* depend on its historical behavior.
56*
57*Entry:
58* The global variable _[a|w]cmdln is set to point at the complete
59* command line.
60*
61*Exit:
62* Returns a pointer to the command line tail.
63*
64*Exceptions:
65*
66*******************************************************************************/
67template <typename Character>
68static Character* __cdecl common_wincmdln() throw()
69{
70 do_locale_initialization(Character());
71
72 static Character empty_string[] = { '\0' };
73
74 Character* command_line = get_command_line(Character()) == nullptr
75 ? empty_string
76 : get_command_line(Character());
77
78 // Skip past the program name (the first token in the command line) and
79 // check for and handle a quoted program name:
80 bool in_double_quotes = false;
81 while (*command_line > ' ' || (*command_line != '\0' && in_double_quotes))
82 {
83 // Toggle the in_double_quotes flag if the current character is '"'
84 if (*command_line == '"')
85 in_double_quotes = !in_double_quotes;
86
87 if (should_copy_another_character(*command_line))
88 ++command_line;
89
90 ++command_line;
91 }
92
93 // Skip past any whitespace preceding the next token:
94 while (*command_line != '\0' && *command_line <= ' ')
95 ++command_line;
96
97 return command_line;
98}
99
100
101
102extern "C" char* __cdecl _get_narrow_winmain_command_line()
103{ // Need to use unsigned char so that we correctly handle ASCII characters
104 // above 127, in particular the comparison to ' ' (space - 0x20).
105 return reinterpret_cast<char *>(common_wincmdln<unsigned char>());
106}
107
108extern "C" wchar_t* __cdecl _get_wide_winmain_command_line()
109{
110 return common_wincmdln<wchar_t>();
111}