[PATCH pve-common v2 08/10] tools: add helpers for version comparison

[David Riley <d.riley@proxmox.com>]

Move 'version_cmp' and 'pvecfg_min_version' over from qemu-server, to
make them more accessible.

Originally-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Originally-by: Alexandre Derumier <aderumier@odiso.com>
Signed-off-by: David Riley <d.riley@proxmox.com>
---
 src/PVE/Tools.pm | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/src/PVE/Tools.pm b/src/PVE/Tools.pm
index 0513fe1..7e66546 100644
--- a/src/PVE/Tools.pm
+++ b/src/PVE/Tools.pm
@@ -54,6 +54,8 @@ our @EXPORT_OK = qw(
     extract_sensitive_params
     file_copy
     get_host_arch
+    pvecfg_min_version
+    version_cmp
     O_PATH
     O_CLOEXEC
     O_TMPFILE
@@ -1945,4 +1947,43 @@ sub is_deeply {
     return 1;
 }
 
+sub pvecfg_min_version {
+    my ($verstr, $major, $minor, $release) = @_;
+
+    return 0 if !$verstr;
+
+    if ($verstr =~ m/^(\d+)\.(\d+)(?:[.-](\d+))?/) {
+        return 1 if version_cmp($1, $major, $2, $minor, $3 // 0, $release) >= 0;
+        return 0;
+    }
+
+    die "internal error: cannot check version of invalid string '$verstr'";
+}
+
+# gets in pairs the versions you want to compares, i.e.:
+# ($a-major, $b-major, $a-minor, $b-minor, $a-extra, $b-extra, ...)
+# returns 0 if same, -1 if $a is older than $b, +1 if $a is newer than $b
+sub version_cmp {
+    my @versions = @_;
+
+    my $size = scalar(@versions);
+
+    return 0 if $size == 0;
+
+    if ($size & 1) {
+        my (undef, $fn, $line) = caller(0);
+        die "cannot compare odd count of versions, called from $fn:$line\n";
+    }
+
+    for (my $i = 0; $i < $size; $i += 2) {
+        my ($left, $right) = splice(@versions, 0, 2);
+        $left //= 0;
+        $right //= 0;
+
+        return 1 if $left > $right;
+        return -1 if $left < $right;
+    }
+    return 0;
+}
+
 1;
-- 
2.47.3