Currently we wrap our fd inside a FILE* stream to make use of vfprintf, but the man page leaves the question of errno and signal handling in doubt. It is documented as returning a negative value and setting ferror(), but we have been interpreting errno to handle signal restarting. As that is in doubt, reduce it to a sprintf and reuse our common interrupt handling write() that already returns -errno.
Signed-off-by: Chris Wilson <[email protected]> Cc: Katarzyna Dec <[email protected]> --- lib/igt_sysfs.c | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/lib/igt_sysfs.c b/lib/igt_sysfs.c index 8efe889be..b39da4c2a 100644 --- a/lib/igt_sysfs.c +++ b/lib/igt_sysfs.c @@ -387,22 +387,37 @@ int igt_sysfs_scanf(int dir, const char *attr, const char *fmt, ...) int igt_sysfs_vprintf(int dir, const char *attr, const char *fmt, va_list ap) { - FILE *file; - int fd; - int ret = -1; + char stack[128], *buf = stack; + va_list tmp; + int ret, fd; fd = openat(dir, attr, O_WRONLY); if (fd < 0) - return -1; + return -errno; - file = fdopen(fd, "w"); - if (file) { - do { - ret = vfprintf(file, fmt, ap); - } while (ret == -1 && errno == EINTR); - fclose(file); + va_copy(tmp, ap); + ret = vsnprintf(buf, sizeof(stack), fmt, tmp); + va_end(tmp); + if (ret < 0) + return -EINVAL; + + if (ret > sizeof(stack)) { + int len = ret + 1; + + buf = malloc(len); + if (!buf) + return -ENOMEM; + + ret = vsnprintf(buf, ret, fmt, ap); + if (ret > len) { + free(buf); + return -EINVAL; + } } - close(fd); + + ret = writeN(fd, buf, ret); + if (buf != stack) + free(buf); return ret; } -- 2.19.0.rc1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
