Merge branch 'js/trace2-to-directory'
The trace2 tracing facility learned to auto-generate a filename
when told to log to a directory.
* js/trace2-to-directory:
trace2: write to directory targets
diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt
index 2de565f..d0948ba 100644
--- a/Documentation/technical/api-trace2.txt
+++ b/Documentation/technical/api-trace2.txt
@@ -109,6 +109,11 @@
Enables the target, opens and writes to the file in append mode.
+ If the target already exists and is a directory, the traces will be
+ written to files (one per process) underneath the given directory. They
+ will be named according to the last component of the SID (optionally
+ followed by a counter to avoid filename collisions).
+
`af_unix:[<socket_type>:]<absolute-pathname>`::
Enables the target, opens and writes to a Unix Domain Socket
diff --git a/t/t0210-trace2-normal.sh b/t/t0210-trace2-normal.sh
index 03a0aed..8194306 100755
--- a/t/t0210-trace2-normal.sh
+++ b/t/t0210-trace2-normal.sh
@@ -80,6 +80,21 @@
test_cmp expect actual
'
+test_expect_success 'automatic filename' '
+ test_when_finished "rm -r traces actual expect" &&
+ mkdir traces &&
+ GIT_TR2="$(pwd)/traces" test-tool trace2 001return 0 &&
+ perl "$TEST_DIRECTORY/t0210/scrub_normal.perl" <"$(ls traces/*)" >actual &&
+ cat >expect <<-EOF &&
+ version $V
+ start _EXE_ trace2 001return 0
+ cmd_name trace2 (trace2)
+ exit elapsed:_TIME_ code:0
+ atexit elapsed:_TIME_ code:0
+ EOF
+ test_cmp expect actual
+'
+
# Verb 002exit
#
# Explicit exit(code) from within cmd_<verb> propagates <code>.
diff --git a/trace2/tr2_dst.c b/trace2/tr2_dst.c
index fd490a4..c3d82ca 100644
--- a/trace2/tr2_dst.c
+++ b/trace2/tr2_dst.c
@@ -1,5 +1,6 @@
#include "cache.h"
#include "trace2/tr2_dst.h"
+#include "trace2/tr2_sid.h"
/*
* If a Trace2 target cannot be opened for writing, we should issue a
@@ -12,6 +13,11 @@
*/
#define TR2_ENVVAR_DST_DEBUG "GIT_TR2_DST_DEBUG"
+/*
+ * How many attempts we will make at creating an automatically-named trace file.
+ */
+#define MAX_AUTO_ATTEMPTS 10
+
static int tr2_dst_want_warning(void)
{
static int tr2env_dst_debug = -1;
@@ -36,6 +42,55 @@
dst->need_close = 0;
}
+static int tr2_dst_try_auto_path(struct tr2_dst *dst, const char *tgt_prefix)
+{
+ int fd;
+ const char *last_slash, *sid = tr2_sid_get();
+ struct strbuf path = STRBUF_INIT;
+ size_t base_path_len;
+ unsigned attempt_count;
+
+ last_slash = strrchr(sid, '/');
+ if (last_slash)
+ sid = last_slash + 1;
+
+ strbuf_addstr(&path, tgt_prefix);
+ if (!is_dir_sep(path.buf[path.len - 1]))
+ strbuf_addch(&path, '/');
+ strbuf_addstr(&path, sid);
+ base_path_len = path.len;
+
+ for (attempt_count = 0; attempt_count < MAX_AUTO_ATTEMPTS; attempt_count++) {
+ if (attempt_count > 0) {
+ strbuf_setlen(&path, base_path_len);
+ strbuf_addf(&path, ".%d", attempt_count);
+ }
+
+ fd = open(path.buf, O_WRONLY | O_CREAT | O_EXCL, 0666);
+ if (fd != -1)
+ break;
+ }
+
+ if (fd == -1) {
+ if (tr2_dst_want_warning())
+ warning("trace2: could not open '%.*s' for '%s' tracing: %s",
+ (int) base_path_len, path.buf,
+ dst->env_var_name, strerror(errno));
+
+ tr2_dst_trace_disable(dst);
+ strbuf_release(&path);
+ return 0;
+ }
+
+ strbuf_release(&path);
+
+ dst->fd = fd;
+ dst->need_close = 1;
+ dst->initialized = 1;
+
+ return dst->fd;
+}
+
static int tr2_dst_try_path(struct tr2_dst *dst, const char *tgt_value)
{
int fd = open(tgt_value, O_WRONLY | O_APPEND | O_CREAT, 0666);
@@ -202,8 +257,12 @@
return dst->fd;
}
- if (is_absolute_path(tgt_value))
- return tr2_dst_try_path(dst, tgt_value);
+ if (is_absolute_path(tgt_value)) {
+ if (is_directory(tgt_value))
+ return tr2_dst_try_auto_path(dst, tgt_value);
+ else
+ return tr2_dst_try_path(dst, tgt_value);
+ }
#ifndef NO_UNIX_SOCKETS
if (starts_with(tgt_value, PREFIX_AF_UNIX))
