Currently, cg_read()/cg_write() returns 0 on success and -1 on failure. Modify them to return the -errno on failure.
Signed-off-by: Yosry Ahmed yosryahmed@google.com --- tools/testing/selftests/cgroup/cgroup_util.c | 44 +++++++++----------- 1 file changed, 19 insertions(+), 25 deletions(-)
diff --git a/tools/testing/selftests/cgroup/cgroup_util.c b/tools/testing/selftests/cgroup/cgroup_util.c index dbaa7aabbb4a..e6f3679cdcc0 100644 --- a/tools/testing/selftests/cgroup/cgroup_util.c +++ b/tools/testing/selftests/cgroup/cgroup_util.c @@ -19,6 +19,7 @@ #include "cgroup_util.h" #include "../clone3/clone3_selftests.h"
+/* Returns read len on success, or -errno on failure. */ static ssize_t read_text(const char *path, char *buf, size_t max_len) { ssize_t len; @@ -26,35 +27,29 @@ static ssize_t read_text(const char *path, char *buf, size_t max_len)
fd = open(path, O_RDONLY); if (fd < 0) - return fd; + return -errno;
len = read(fd, buf, max_len - 1); - if (len < 0) - goto out;
- buf[len] = 0; -out: + if (len >= 0) + buf[len] = 0; + close(fd); - return len; + return len < 0 ? -errno : len; }
+/* Returns written len on success, or -errno on failure. */ static ssize_t write_text(const char *path, char *buf, ssize_t len) { int fd;
fd = open(path, O_WRONLY | O_APPEND); if (fd < 0) - return fd; + return -errno;
len = write(fd, buf, len); - if (len < 0) { - close(fd); - return len; - } - close(fd); - - return len; + return len < 0 ? -errno : len; }
char *cg_name(const char *root, const char *name) @@ -87,16 +82,16 @@ char *cg_control(const char *cgroup, const char *control) return ret; }
+/* Returns 0 on success, or -errno on failure. */ int cg_read(const char *cgroup, const char *control, char *buf, size_t len) { char path[PATH_MAX]; + ssize_t ret;
snprintf(path, sizeof(path), "%s/%s", cgroup, control);
- if (read_text(path, buf, len) >= 0) - return 0; - - return -1; + ret = read_text(path, buf, len); + return ret >= 0 ? 0 : ret; }
int cg_read_strcmp(const char *cgroup, const char *control, @@ -177,17 +172,15 @@ long cg_read_lc(const char *cgroup, const char *control) return cnt; }
+/* Returns 0 on success, or -errno on failure. */ int cg_write(const char *cgroup, const char *control, char *buf) { char path[PATH_MAX]; - ssize_t len = strlen(buf); + ssize_t len = strlen(buf), ret;
snprintf(path, sizeof(path), "%s/%s", cgroup, control); - - if (write_text(path, buf, len) == len) - return 0; - - return -1; + ret = write_text(path, buf, len); + return ret == len ? 0 : ret; }
int cg_find_unified_root(char *root, size_t len) @@ -545,7 +538,8 @@ ssize_t proc_read_text(int pid, bool thread, const char *item, char *buf, size_t else snprintf(path, sizeof(path), "/proc/%d/%s", pid, item);
- return read_text(path, buf, size); + size = read_text(path, buf, size); + return size < 0 ? -1 : size; }
int proc_read_strstr(int pid, bool thread, const char *item, const char *needle)