lix/src/nix-env/names.cc
Eelco Dolstra 618aa69b01 * In --upgrade': added flags --lt', --leq', --always' to specify
whether we want to upgrade if the current version is less than the
  available version (default), when it is less or equal, or always.
  
* Added a flag `--dry-run' to show what would happen in `--install',
  `--uninstall', and `--upgrade', without actually performing the
  operation.
2004-02-09 11:59:39 +00:00

128 lines
3.2 KiB
C++

#include "names.hh"
DrvName::DrvName()
{
name = "";
}
/* Parse a derivation name. The `name' part of a derivation name is
everything up to but not including the first dash *not* followed by
a letter. The `version' part is the rest (excluding the separating
dash). E.g., `apache-httpd-2.0.48' is parsed to (`apache-httpd',
'2.0.48'). */
DrvName::DrvName(const string & s) : hits(0)
{
name = fullName = s;
for (unsigned int i = 0; i < s.size(); ++i) {
/* !!! isalpha/isdigit are affected by the locale. */
if (s[i] == '-' && i + 1 < s.size() && !isalpha(s[i + 1])) {
name = string(s, 0, i);
version = string(s, i + 1);
break;
}
}
}
bool DrvName::matches(DrvName & n)
{
if (name != "*" && name != n.name) return false;
if (version != "" && version != n.version) return false;
return true;
}
static string nextComponent(string::const_iterator & p,
const string::const_iterator end)
{
/* Skip any dots and dashes (component separators). */
while (p != end && (*p == '.' || *p == '-')) ++p;
if (p == end) return "";
/* 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;
if (isdigit(*p))
while (p != end && isdigit(*p)) s += *p++;
else
while (p != end && (!isdigit(*p) && *p != '.' && *p != '-'))
s += *p++;
return s;
}
#include <fstream>
static bool parseInt(const string & s, int & n)
{
istringstream st(s);
st >> n;
return !st.fail();
}
static bool componentsLT(const string & c1, const string & c2)
{
int n1, n2;
bool c1Num = parseInt(c1, n1), c2Num = parseInt(c2, n2);
if (c1Num && c2Num) return n1 < n2;
else if (c1 == "" && c2Num) return true;
else if (c1 == "pre" && c2 != "pre") return true;
else if (c2 == "pre") return false;
/* Assume that `2.3a' < `2.3.1'. */
else if (c2Num) return true;
else if (c1Num) return false;
else return c1 < c2;
}
int compareVersions(const string & v1, const string & v2)
{
string::const_iterator p1 = v1.begin();
string::const_iterator p2 = v2.begin();
while (p1 != v1.end() || p2 != v2.end()) {
string c1 = nextComponent(p1, v1.end());
string c2 = nextComponent(p2, v2.end());
if (componentsLT(c1, c2)) return -1;
else if (componentsLT(c2, c1)) return 1;
}
return 0;
}
static void testCompareVersions()
{
#define TEST(v1, v2, n) assert( \
compareVersions(v1, v2) == n && compareVersions(v2, v1) == -n)
TEST("1.0", "2.3", -1);
TEST("2.1", "2.3", -1);
TEST("2.3", "2.3", 0);
TEST("2.5", "2.3", 1);
TEST("3.1", "2.3", 1);
TEST("2.3.1", "2.3", 1);
TEST("2.3.1", "2.3a", 1);
TEST("2.3pre1", "2.3", -1);
TEST("2.3pre3", "2.3pre12", -1);
TEST("2.3a", "2.3c", -1);
TEST("2.3pre1", "2.3c", -1);
TEST("2.3pre1", "2.3q", -1);
}
DrvNames drvNamesFromArgs(const Strings & opArgs)
{
DrvNames result;
for (Strings::const_iterator i = opArgs.begin();
i != opArgs.end(); ++i)
result.push_back(DrvName(*i));
return result;
}