[php-src] PHP-8.4: Fix wordwrap() ignoring an existing break at the end of the string (#24116)

Author: Nicolas Grekas (nicolas-grekas) Committer: GitHub (web-flow) Pusher: arnaud-lb Date: 2026-10-05T19:44:36+02:00 Commit: https://github.com/php/php-src/commit/f817996280d7dc184a27b93dca29a2e4a8633090 Raw diff: https://github.com/php/php-src/commit/f817996280d7dc184a27b93dca29a2e4a8633090.diff Fix wordwrap() ignoring an existing break at the end of the string (#24116) When a multi-character break or $cut_long_words is used, an existing break was only recognized when at least one character followed it. A trailing break was handled as regular text, so wordwrap("abc\n", 3, "\n", true) returned "abc\n\n" and wordwrap("ab cd\n", 5, "\n", true) returned "ab\ncd\n". The single-character fast path was not affected. Changed paths: A ext/standard/tests/strings/wordwrap_trailing_break.phpt M NEWS M ext/standard/string.c Diff: diff --git a/NEWS b/NEWS index 6134971c6ba6..14b0d0b08db1 100644 --- a/NEWS +++ b/NEWS @@ -219,6 +219,8 @@ PHP NEWS PROCESS_INFORMATION, an indeterminate comspec pointer after a failed lookup, and an unchecked CreateFileA() failure. (Ilia Alshanetsky) . Fix persistent stream context lifetime during shutdown (Levi Morrison) + . Fix wordwrap() ignoring an existing break at the end of the string + (Nicolas Grekas) - Tidy: . Fixed a use-after-free when a tidyNode is used after its document is diff --git a/ext/standard/string.c b/ext/standard/string.c index 34444d80d185..40b05135a8e8 100644 --- a/ext/standard/string.c +++ b/ext/standard/string.c @@ -779,7 +779,7 @@ PHP_FUNCTION(wordwrap) /* when we hit an existing break, copy to new buffer, and * fix up laststart and lastspace */ if (ZSTR_VAL(text)[current] == breakchar[0] - && current + breakchar_len < ZSTR_LEN(text) + && current + breakchar_len <= ZSTR_LEN(text) && !strncmp(ZSTR_VAL(text) + current, breakchar, breakchar_len)) { memcpy(ZSTR_VAL(newtext) + newtextlen, ZSTR_VAL(text) + laststart, current - laststart + breakchar_len); newtextlen += current - laststart + breakchar_len; diff --git a/ext/standard/tests/strings/wordwrap_trailing_break.phpt b/ext/standard/tests/strings/wordwrap_trailing_break.phpt new file mode 100644 index 000000000000..2e57ce176665 --- /dev/null +++ b/ext/standard/tests/strings/wordwrap_trailing_break.phpt @@ -0,0 +1,28 @@ +--TEST-- +wordwrap() recognizes an existing break at the end of the string +--FILE-- +<?php +$tests = [ + ["abc\n", 3, "\n", true], + ["ab cd\n", 5, "\n", true], + ["abcd\n", 3, "\n", true], + ["abc\nabc\n", 3, "\n", true], + ["abc-", 3, "-", true], + ["abc\r\n", 3, "\r\n", true], + ["\r\n", 1, "\r\n", true], + ["ab cd\r\n", 5, "\r\n", false], +]; + +foreach ($tests as [$text, $width, $break, $cut]) { + echo json_encode(wordwrap($text, $width, $break, $cut)), "\n"; +} +?> +--EXPECT-- +"abc\n" +"ab cd\n" +"abc\nd\n" +"abc\nabc\n" +"abc-" +"abc\r\n" +"\r\n" +"ab cd\r\n"