[PATCH 1/7] trace: handle NULL argument in trace_disable()
- From
Jeff King <peff@peff.net>
- Date
- Aug 3, 2016, 22:56 UTC
- Message-ID
- <20160803225657.vdjih5mzvdmilx4d@sigill.intra.peff.net>
- In-Reply-To
- <20160803225600.fgm23bdacunmrw44@sigill.intra.peff.net>
All of the trace functions treat a NULL key as a synonym for the default GIT_TRACE key. Except for trace_disable(), which will segfault.
Fortunately, this can't cause any bugs, as the function has no callers. But rather than drop it, let's fix the bug, as I plan to add a caller.
Signed-off-by: Jeff King <peff@peff.net> --- trace.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/trace.c b/trace.c index 4aeea60..f204a7d 100644 --- a/trace.c +++ b/trace.c @@ -25,15 +25,25 @@ #include "cache.h" #include "quote.h" +/* + * "Normalize" a key argument by converting NULL to our trace_default, + * and otherwise passing through the value. All caller-facing functions + * should normalize their inputs in this way, though most get it + * for free by calling get_trace_fd() (directly or indirectly). + */ +static void normalize_trace_key(struct trace_key **key) +{ + static struct trace_key trace_default = { "GIT_TRACE" }; + if (!*key) + *key = &trace_default; +} + /* Get a trace file descriptor from "key" env variable. */ static int get_trace_fd(struct trace_key *key) { - static struct trace_key trace_default = { "GIT_TRACE" }; const char *trace; - /* use default "GIT_TRACE" if NULL */ - if (!key) - key = &trace_default; + normalize_trace_key(&key); /* don't open twice */ if (key->initialized) @@ -75,6 +85,8 @@ static int get_trace_fd(struct trace_key *key) void trace_disable(struct trace_key *key) { + normalize_trace_key(&key); + if (key->need_close) close(key->fd); key->fd = 0;
-- 2.9.2.670.g42e63de