commit 4bb831e0873e7e4468a44dbf9e253bcd5df18421 Author: Nick Mathewson nickm@torproject.org Date: Tue Jan 16 12:42:40 2018 -0500
Improve fragile-hardening performance of consensus_split_lines.
For whatever reason, in my testing, using memchr() here improves performance over strchr() by a great deal.
Fixes bug 24826; bugfix on 0.3.1.1-alpha. --- changes/bug24826_031 | 4 ++++ src/or/consdiff.c | 5 ++++- 2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/changes/bug24826_031 b/changes/bug24826_031 new file mode 100644 index 000000000..3d4a66184 --- /dev/null +++ b/changes/bug24826_031 @@ -0,0 +1,4 @@ + o Minor bugfixes (performance, fragile-hardening): + - Improve the performance of our consensus-diff application code when Tor + is built with the --enable-fragile-hardening option set. Fixes bug + 24826; bugfix on 0.3.1.1-alpha. diff --git a/src/or/consdiff.c b/src/or/consdiff.c index 1baa11897..deaf465fe 100644 --- a/src/or/consdiff.c +++ b/src/or/consdiff.c @@ -1285,8 +1285,11 @@ consdiff_apply_diff(const smartlist_t *cons1, STATIC int consensus_split_lines(smartlist_t *out, const char *s, memarea_t *area) { + const char *end_of_str = s + strlen(s); + tor_assert(*end_of_str == '\0'); + while (*s) { - const char *eol = strchr(s, '\n'); + const char *eol = memchr(s, '\n', end_of_str - s); if (!eol) { /* File doesn't end with newline. */ return -1;