#28800 [Ver->Csd]: Strings beginning with "inf" improperly converted

ID: 28800 Updated by: iliaa@php.net Reported By: pmichaud at pobox dot com -Status: Verified +Status: Closed Bug Type: Scripting Engine problem Operating System: Linux PHP Version: 4.3.6, 5.0.0RC2 New Comment: This bug has been fixed in CVS. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. Thank you for the report, and for helping us make PHP better. Previous Comments: ------------------------------------------------------------------------ [2004-06-28 12:35:23] rasmus@php.net Verified that this is indeed the case. Since we are using strtol() internally here, I would actually expect INF for both your "inf" and "infinity" cases. The strtol() spec says that this should be the result. And a quick local check verifies this, but the others definitely shouldn't be returning INF. It looks like we are not checking the end pointer returned from strtol() at all in any of our conversion functions. We need something like this: l = strtol(s, &endp, 0); if (s != endp && *endp == `\0') { ... valid conversion ... } ------------------------------------------------------------------------ [2004-06-20 05:08:46] pmichaud at pobox dot com Changed PHP version number to note bug exists in 5.0.0RC2. ------------------------------------------------------------------------ [2004-06-20 05:05:27] pmichaud at pobox dot com Changed PHP version number to note reports of bug in many versions of PHP. ------------------------------------------------------------------------ [2004-06-20 04:49:31] pmichaud at pobox dot com Changed bug category. ------------------------------------------------------------------------ [2004-06-15 22:26:40] pmichaud at pobox dot com Description: ------------ PHP seems to incorrectly convert strings beginning with "inf" to INF (infinity). This includes converting strings such as "info" and "inflammable". Surprisingly, the strings "inf" and "infinity" do *not* convert to infinity but correctly become zeros. A script that illustrates the problem is given below: This is very annoying because one cannot simply do a test for a positive number with code such as if ($x>0) { echo "$x is positive"; } because if $x is any string beginning with "inf" (but not "inf" or "infinity") it is treated as a positive number. Pm Reproduce code: --------------- Here's a script that illustrates the problem: <?php header("Content-type: text/plain"); $a = "into"; $b = "info"; $c = "inf"; $d = "infinity"; $e = "infin"; $f = "inflammable"; echo "a: $a == ",$a+0,"\n"; # outputs 0 (correct) echo "b: $b == ",$b+0,"\n"; # outputs INF, incorrect! echo "c: $c == ",$c+0,"\n"; # outputs 0 (?!) echo "d: $d == ",$d+0,"\n"; # outputs 0 (?!) echo "e: $e == ",$e+0,"\n"; # outputs INF, incorrect! echo "f: $f == ",$f+0,"\n"; # outputs INF, incorrect! ?> Expected result: ---------------- a: into == 0 b: info == 0 c: inf == 0 d: infinity == 0 e: infin == 0 f: inflammable == 0 Actual result: -------------- a: into == 0 b: info == INF c: inf == 0 d: infinity == 0 e: infin == INF f: inflammable == INF ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=28800&edit=1