Commit e588c116 authored by Wang Yufen's avatar Wang Yufen Committed by Andrii Nakryiko
Browse files

libbpf: Add pathname_concat() helper 



Move snprintf and len check to common helper pathname_concat() to make the
code simpler.

Signed-off-by: default avatarWang Yufen <wangyufen@huawei.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1663828124-10437-1-git-send-email-wangyufen@huawei.com
parent e0401dce

tools/lib/bpf/libbpf.c

+29 −47
Original line number Diff line number Diff line
@@ -2097,19 +2097,30 @@ static bool get_map_field_int(const char *map_name, const struct btf *btf, 
	return true;

}



static int pathname_concat(char *buf, size_t buf_sz, const char *path, const char *name)

{

	int len;



	len = snprintf(buf, buf_sz, "%s/%s", path, name);

	if (len < 0)

		return -EINVAL;

	if (len >= buf_sz)

		return -ENAMETOOLONG;



	return 0;

}



static int build_map_pin_path(struct bpf_map *map, const char *path)

{

	char buf[PATH_MAX];

	int len;

	int err;



	if (!path)

		path = "/sys/fs/bpf";



	len = snprintf(buf, PATH_MAX, "%s/%s", path, bpf_map__name(map));

	if (len < 0)

		return -EINVAL;

	else if (len >= PATH_MAX)

		return -ENAMETOOLONG;

	err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));

	if (err)

		return err;



	return bpf_map__set_pin_path(map, buf);

}
@@ -7968,17 +7979,9 @@ int bpf_object__pin_maps(struct bpf_object *obj, const char *path) 
			continue;



		if (path) {

			int len;



			len = snprintf(buf, PATH_MAX, "%s/%s", path,

				       bpf_map__name(map));

			if (len < 0) {

				err = -EINVAL;

				goto err_unpin_maps;

			} else if (len >= PATH_MAX) {

				err = -ENAMETOOLONG;

			err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));

			if (err)

				goto err_unpin_maps;

			}

			sanitize_pin_path(buf);

			pin_path = buf;

		} else if (!map->pin_path) {
@@ -8016,14 +8019,9 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path) 
		char buf[PATH_MAX];



		if (path) {

			int len;



			len = snprintf(buf, PATH_MAX, "%s/%s", path,

				       bpf_map__name(map));

			if (len < 0)

				return libbpf_err(-EINVAL);

			else if (len >= PATH_MAX)

				return libbpf_err(-ENAMETOOLONG);

			err = pathname_concat(buf, sizeof(buf), path, bpf_map__name(map));

			if (err)

				return libbpf_err(err);

			sanitize_pin_path(buf);

			pin_path = buf;

		} else if (!map->pin_path) {
@@ -8041,6 +8039,7 @@ int bpf_object__unpin_maps(struct bpf_object *obj, const char *path) 
int bpf_object__pin_programs(struct bpf_object *obj, const char *path)

{

	struct bpf_program *prog;

	char buf[PATH_MAX];

	int err;



	if (!obj)
@@ -8052,17 +8051,9 @@ int bpf_object__pin_programs(struct bpf_object *obj, const char *path) 
	}



	bpf_object__for_each_program(prog, obj) {

		char buf[PATH_MAX];

		int len;



		len = snprintf(buf, PATH_MAX, "%s/%s", path, prog->name);

		if (len < 0) {

			err = -EINVAL;

			goto err_unpin_programs;

		} else if (len >= PATH_MAX) {

			err = -ENAMETOOLONG;

		err = pathname_concat(buf, sizeof(buf), path, prog->name);

		if (err)

			goto err_unpin_programs;

		}



		err = bpf_program__pin(prog, buf);

		if (err)
@@ -8073,13 +8064,7 @@ int bpf_object__pin_programs(struct bpf_object *obj, const char *path) 


err_unpin_programs:

	while ((prog = bpf_object__prev_program(obj, prog))) {

		char buf[PATH_MAX];

		int len;



		len = snprintf(buf, PATH_MAX, "%s/%s", path, prog->name);

		if (len < 0)

			continue;

		else if (len >= PATH_MAX)

		if (pathname_concat(buf, sizeof(buf), path, prog->name))

			continue;



		bpf_program__unpin(prog, buf);
@@ -8098,13 +8083,10 @@ int bpf_object__unpin_programs(struct bpf_object *obj, const char *path) 


	bpf_object__for_each_program(prog, obj) {

		char buf[PATH_MAX];

		int len;



		len = snprintf(buf, PATH_MAX, "%s/%s", path, prog->name);

		if (len < 0)

			return libbpf_err(-EINVAL);

		else if (len >= PATH_MAX)

			return libbpf_err(-ENAMETOOLONG);

		err = pathname_concat(buf, sizeof(buf), path, prog->name);

		if (err)

			return libbpf_err(err);



		err = bpf_program__unpin(prog, buf);

		if (err)