Message ID | cover.1553202340.git.steadmon@google.com (mailing list archive) |
---|---|
Headers | show |
Series | Write trace2 output to directories | expand |
On 3/21/2019 5:09 PM, Josh Steadmon wrote: > Persistently enabling trace2 output is difficult because it requires > specifying a full filename. This series teaches tr2_dst_get_trace_fd() > to create files underneath a given directory provided as the target of > the GIT_TR2_* envvars. > > Changes since V2: > * No longer appends a suffix to filenames on the first creation attempt. > * Renamed function & constant now that randomization is no longer used. > * Simplified strbuf usage. > > Changes since V1: > * No longer supports timestamp templates. > * No longer supports filename prefixes. > * Always creates filenames based on the final component of the trace2 > SID. > > Josh Steadmon (1): > trace2: write to directory targets > > Documentation/technical/api-trace2.txt | 5 ++ > t/t0210-trace2-normal.sh | 15 ++++++ > trace2/tr2_dst.c | 63 +++++++++++++++++++++++++- > 3 files changed, 81 insertions(+), 2 deletions(-) > > Range-diff against v2: > 1: 59d8c6511b ! 1: ce5258610f trace2: write to directory targets > @@ -23,8 +23,8 @@ > > + 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 followed by a > -+ counter to avoid potential collisions. > ++ 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>`:: > > @@ -37,7 +37,7 @@ > test_cmp expect actual > ' > > -+test_expect_success 'randomized filename' ' > ++test_expect_success 'automatic filename' ' > + test_when_finished "rm -r traces actual expect" && > + mkdir traces && > + GIT_TR2="$(pwd)/traces" test-tool trace2 001return 0 && > @@ -71,9 +71,9 @@ > #define TR2_ENVVAR_DST_DEBUG "GIT_TR2_DST_DEBUG" > > +/* > -+ * How many attempts we will make at creating a random trace output path. > ++ * How many attempts we will make at creating an automatically-named trace file. > + */ > -+#define MAX_RANDOM_ATTEMPTS 10 > ++#define MAX_AUTO_ATTEMPTS 10 > + > static int tr2_dst_want_warning(void) > { > @@ -82,45 +82,47 @@ > dst->need_close = 0; > } > > -+static int tr2_dst_try_random_path(struct tr2_dst *dst, const char *tgt_prefix) > ++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 base_path = STRBUF_INIT, final_path = STRBUF_INIT; > ++ 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(&base_path, tgt_prefix); > -+ if (!is_dir_sep(base_path.buf[base_path.len - 1])) > -+ strbuf_addch(&base_path, '/'); > -+ strbuf_addstr(&base_path, sid); > ++ 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_RANDOM_ATTEMPTS; attempt_count++) { > -+ strbuf_reset(&final_path); > -+ strbuf_addbuf(&final_path, &base_path); > -+ strbuf_addf(&final_path, ".%d", attempt_count); > ++ 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(final_path.buf, O_WRONLY | O_CREAT | O_EXCL, 0666); > ++ 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", > -+ base_path.buf, dst->env_var_name, strerror(errno)); > ++ 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(&base_path); > -+ strbuf_release(&final_path); > ++ strbuf_release(&path); > + return 0; > + } > + > -+ strbuf_release(&base_path); > -+ strbuf_release(&final_path); > ++ strbuf_release(&path); > + > + dst->fd = fd; > + dst->need_close = 1; > @@ -140,7 +142,7 @@ > - return tr2_dst_try_path(dst, tgt_value); > + if (is_absolute_path(tgt_value)) { > + if (is_directory(tgt_value)) > -+ return tr2_dst_try_random_path(dst, tgt_value); > ++ return tr2_dst_try_auto_path(dst, tgt_value); > + else > + return tr2_dst_try_path(dst, tgt_value); > + } > Looks good. Thanks. Jeff
Jeff Hostetler <git@jeffhostetler.com> writes: > On 3/21/2019 5:09 PM, Josh Steadmon wrote: >> Persistently enabling trace2 output is difficult because it requires >> specifying a full filename. This series teaches tr2_dst_get_trace_fd() >> to create files underneath a given directory provided as the target of >> the GIT_TR2_* envvars. > ... > Looks good. Thanks. > Jeff Thanks, both. Will queue.