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return string_views from forceString*

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once a string has been forced we already have dynamic storage allocated for it,
so we can easily reuse that storage instead of copying.
This commit is contained in:
pennae 2022-01-21 14:44:00 +01:00
parent 0d7fae6a57
commit 41d70a2fc8
19 changed files with 94 additions and 87 deletions
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24
src/libstore/names.cc
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@ -56,8 +56,8 @@ bool DrvName::matches(const DrvName & n)
}
string nextComponent(string::const_iterator & p,
const string::const_iterator end)
std::string_view nextComponent(std::string_view::const_iterator & p,
const std::string_view::const_iterator end)
{
/* Skip any dots and dashes (component separators). */
while (p != end && (*p == '.' || *p == '-')) ++p;
@ -67,18 +67,18 @@ string nextComponent(string::const_iterator & p,
/* If the first character is a digit, consume the longest sequence
of digits. Otherwise, consume the longest sequence of
non-digit, non-separator characters. */
string s;
auto s = p;
if (isdigit(*p))
while (p != end && isdigit(*p)) s += *p++;
while (p != end && isdigit(*p)) p++;
else
while (p != end && (!isdigit(*p) && *p != '.' && *p != '-'))
s += *p++;
p++;
return s;
return {s, size_t(p - s)};
}
static bool componentsLT(const string & c1, const string & c2)
static bool componentsLT(const std::string_view c1, const std::string_view c2)
{
auto n1 = string2Int<int>(c1);
auto n2 = string2Int<int>(c2);
@ -94,14 +94,14 @@ static bool componentsLT(const string & c1, const string & c2)
}
int compareVersions(const string & v1, const string & v2)
int compareVersions(const std::string_view v1, const std::string_view v2)
{
string::const_iterator p1 = v1.begin();
string::const_iterator p2 = v2.begin();
auto p1 = v1.begin();
auto p2 = v2.begin();
while (p1 != v1.end() || p2 != v2.end()) {
string c1 = nextComponent(p1, v1.end());
string c2 = nextComponent(p2, v2.end());
auto c1 = nextComponent(p1, v1.end());
auto c2 = nextComponent(p2, v2.end());
if (componentsLT(c1, c2)) return -1;
else if (componentsLT(c2, c1)) return 1;
}