selftests/bpf: consolidate and improve file/prog filtering in veristat

Slightly change rules of specifying file/prog glob filters. In practice
it's quite often inconvenient to do `*/<prog-glob>` if that program glob
is unique enough and won't accidentally match any file names.

This patch changes the rules so that `-f <glob>` will apply specified
glob to both file and program names. User still has all the control by
doing '*/<prog-only-glob>' or '<file-only-glob/*'. We also now allow
'/<prog-glob>' and '<file-glob/' (all matching wildcard is assumed if
missing).

Also, internally unify file-only and file+prog checks
(should_process_file and should_process_prog are now
should_process_file_prog that can handle prog name as optional). This
makes maintaining and extending this code easier.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20221103055304.2904589-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/veristat.c b/tools/testing/selftests/bpf/veristat.c
index d553f38..f6f6a24 100644 (file)
--- a/tools/testing/selftests/bpf/veristat.c
+++ b/tools/testing/selftests/bpf/veristat.c
@@ -55,6 +55,7 @@ enum resfmt {
 };
 
 struct filter {
+       char *any_glob;
        char *file_glob;
        char *prog_glob;
 };
@@ -231,28 +232,6 @@ static bool glob_matches(const char *str, const char *pat)
        return !*str && !*pat;
 }
 
-static bool should_process_file(const char *filename)
-{
-       int i;
-
-       if (env.deny_filter_cnt > 0) {
-               for (i = 0; i < env.deny_filter_cnt; i++) {
-                       if (glob_matches(filename, env.deny_filters[i].file_glob))
-                               return false;
-               }
-       }
-
-       if (env.allow_filter_cnt == 0)
-               return true;
-
-       for (i = 0; i < env.allow_filter_cnt; i++) {
-               if (glob_matches(filename, env.allow_filters[i].file_glob))
-                       return true;
-       }
-
-       return false;
-}
-
 static bool is_bpf_obj_file(const char *path) {
        Elf64_Ehdr *ehdr;
        int fd, err = -EINVAL;
@@ -285,38 +264,46 @@ cleanup:
        return err == 0;
 }
 
-static bool should_process_prog(const char *path, const char *prog_name)
+static bool should_process_file_prog(const char *filename, const char *prog_name)
 {
-       const char *filename = basename(path);
-       int i;
+       struct filter *f;
+       int i, allow_cnt = 0;
 
-       if (env.deny_filter_cnt > 0) {
-               for (i = 0; i < env.deny_filter_cnt; i++) {
-                       if (glob_matches(filename, env.deny_filters[i].file_glob))
-                               return false;
-                       if (!env.deny_filters[i].prog_glob)
-                               continue;
-                       if (glob_matches(prog_name, env.deny_filters[i].prog_glob))
-                               return false;
-               }
-       }
+       for (i = 0; i < env.deny_filter_cnt; i++) {
+               f = &env.deny_filters[i];
 
-       if (env.allow_filter_cnt == 0)
-               return true;
+               if (f->any_glob && glob_matches(filename, f->any_glob))
+                       return false;
+               if (f->any_glob && prog_name && glob_matches(prog_name, f->any_glob))
+                       return false;
+               if (f->file_glob && glob_matches(filename, f->file_glob))
+                       return false;
+               if (f->prog_glob && prog_name && glob_matches(prog_name, f->prog_glob))
+                       return false;
+       }
 
        for (i = 0; i < env.allow_filter_cnt; i++) {
-               if (!glob_matches(filename, env.allow_filters[i].file_glob))
-                       continue;
-               /* if filter specifies only filename glob part, it implicitly
-                * allows all progs within that file
-                */
-               if (!env.allow_filters[i].prog_glob)
-                       return true;
-               if (glob_matches(prog_name, env.allow_filters[i].prog_glob))
+               f = &env.allow_filters[i];
+               allow_cnt++;
+
+               if (f->any_glob) {
+                       if (glob_matches(filename, f->any_glob))
+                               return true;
+                       if (prog_name && glob_matches(prog_name, f->any_glob))
+                               return true;
+               } else {
+                       if (f->file_glob && !glob_matches(filename, f->file_glob))
+                               continue;
+                       if (f->prog_glob && prog_name && !glob_matches(prog_name, f->prog_glob))
+                               continue;
                        return true;
+               }
        }
 
-       return false;
+       /* if there are no file/prog name allow filters, allow all progs,
+        * unless they are denied earlier explicitly
+        */
+       return allow_cnt == 0;
 }
 
 static int append_filter(struct filter **filters, int *cnt, const char *str)
@@ -331,26 +318,40 @@ static int append_filter(struct filter **filters, int *cnt, const char *str)
        *filters = tmp;
 
        f = &(*filters)[*cnt];
-       f->file_glob = f->prog_glob = NULL;
-
-       /* filter can be specified either as "<obj-glob>" or "<obj-glob>/<prog-glob>" */
+       memset(f, 0, sizeof(*f));
+
+       /* File/prog filter can be specified either as '<glob>' or
+        * '<file-glob>/<prog-glob>'. In the former case <glob> is applied to
+        * both file and program names. This seems to be way more useful in
+        * practice. If user needs full control, they can use '/<prog-glob>'
+        * form to glob just program name, or '<file-glob>/' to glob only file
+        * name. But usually common <glob> seems to be the most useful and
+        * ergonomic way.
+        */
        p = strchr(str, '/');
        if (!p) {
-               f->file_glob = strdup(str);
-               if (!f->file_glob)
+               f->any_glob = strdup(str);
+               if (!f->any_glob)
                        return -ENOMEM;
        } else {
-               f->file_glob = strndup(str, p - str);
-               f->prog_glob = strdup(p + 1);
-               if (!f->file_glob || !f->prog_glob) {
-                       free(f->file_glob);
-                       free(f->prog_glob);
-                       f->file_glob = f->prog_glob = NULL;
-                       return -ENOMEM;
+               if (str != p) {
+                       /* non-empty file glob */
+                       f->file_glob = strndup(str, p - str);
+                       if (!f->file_glob)
+                               return -ENOMEM;
+               }
+               if (strlen(p + 1) > 0) {
+                       /* non-empty prog glob */
+                       f->prog_glob = strdup(p + 1);
+                       if (!f->prog_glob) {
+                               free(f->file_glob);
+                               f->file_glob = NULL;
+                               return -ENOMEM;
+                       }
                }
        }
 
-       *cnt = *cnt + 1;
+       *cnt += 1;
        return 0;
 }
 
@@ -546,7 +547,7 @@ static int process_prog(const char *filename, struct bpf_object *obj, struct bpf
        int err = 0;
        void *tmp;
 
-       if (!should_process_prog(filename, bpf_program__name(prog))) {
+       if (!should_process_file_prog(basename(filename), bpf_program__name(prog))) {
                env.progs_skipped++;
                return 0;
        }
@@ -602,7 +603,7 @@ static int process_obj(const char *filename)
        LIBBPF_OPTS(bpf_object_open_opts, opts);
        int err = 0, prog_cnt = 0;
 
-       if (!should_process_file(basename(filename))) {
+       if (!should_process_file_prog(basename(filename), NULL)) {
                if (env.verbose)
                        printf("Skipping '%s' due to filters...\n", filename);
                env.files_skipped++;
@@ -980,7 +981,7 @@ static int parse_stats_csv(const char *filename, struct stat_specs *specs,
                 * parsed entire line; if row should be ignored we pretend we
                 * never parsed it
                 */
-               if (!should_process_prog(st->file_name, st->prog_name)) {
+               if (!should_process_file_prog(st->file_name, st->prog_name)) {
                        free(st->file_name);
                        free(st->prog_name);
                        *stat_cntp -= 1;
@@ -1391,11 +1392,13 @@ int main(int argc, char **argv)
                free(env.filenames[i]);
        free(env.filenames);
        for (i = 0; i < env.allow_filter_cnt; i++) {
+               free(env.allow_filters[i].any_glob);
                free(env.allow_filters[i].file_glob);
                free(env.allow_filters[i].prog_glob);
        }
        free(env.allow_filters);
        for (i = 0; i < env.deny_filter_cnt; i++) {
+               free(env.deny_filters[i].any_glob);
                free(env.deny_filters[i].file_glob);
                free(env.deny_filters[i].prog_glob);
        }