diff options
Diffstat (limited to 'tools/perf/util/util.c')
| -rw-r--r-- | tools/perf/util/util.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c index 9440481e9092..6ea0b4ae9569 100644 --- a/tools/perf/util/util.c +++ b/tools/perf/util/util.c @@ -6,6 +6,7 @@ #endif #include <stdio.h> #include <stdlib.h> +#include <linux/kernel.h> /* * XXX We need to find a better place for these things... @@ -151,21 +152,26 @@ unsigned long convert_unit(unsigned long value, char *unit) return value; } +/* + * Read exactly 'n' bytes or return an error. + */ ssize_t readn(int fd, void *buf, size_t n) { void *buf_start = buf; + size_t left = n; - while (n) { - ssize_t ret = read(fd, buf, n); + while (left) { + ssize_t ret = read(fd, buf, left); if (ret <= 0) return ret; - n -= ret; - buf += ret; + left -= ret; + buf += ret; } - return buf - buf_start; + BUG_ON((size_t)(buf - buf_start) != n); + return n; } size_t hex_width(u64 v) |