1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
|
/* Distributed under the OSI-approved BSD 3-Clause License. See accompanying
file Copyright.txt or https://cmake.org/licensing for details. */
#include "cmPlaceholderExpander.h"
#include <cctype>
std::string& cmPlaceholderExpander::ExpandVariables(std::string& s)
{
std::string::size_type start = s.find('<');
// no variables to expand
if (start == std::string::npos) {
return s;
}
std::string::size_type pos = 0;
std::string expandedInput;
while (start != std::string::npos && start < s.size() - 2) {
std::string::size_type end = s.find('>', start);
// if we find a < with no > we are done
if (end == std::string::npos) {
s = expandedInput;
return s;
}
char c = s[start + 1];
// if the next char after the < is not A-Za-z then
// skip it and try to find the next < in the string
if (!isalpha(c)) {
start = s.find('<', start + 1);
} else {
// extract the var
std::string var = s.substr(start + 1, end - start - 1);
std::string replace = this->ExpandVariable(var);
expandedInput += s.substr(pos, start - pos);
// Prevent consecutive whitespace in the output if the rule variable
// expands to an empty string.
bool consecutive = replace.empty() && start > 0 && s[start - 1] == ' ' &&
end + 1 < s.size() && s[end + 1] == ' ';
if (consecutive) {
expandedInput.pop_back();
}
expandedInput += replace;
// move to next one
start = s.find('<', start + var.size() + 2);
pos = end + 1;
}
}
// add the rest of the input
expandedInput += s.substr(pos, s.size() - pos);
// remove trailing whitespace
if (!expandedInput.empty() && expandedInput.back() == ' ') {
expandedInput.pop_back();
}
s = expandedInput;
return s;
}
|
