diff options
| -rw-r--r-- | libc/misc/time/time.c | 33 |
1 files changed, 23 insertions, 10 deletions
diff --git a/libc/misc/time/time.c b/libc/misc/time/time.c index 45ec131b7..168655b00 100644 --- a/libc/misc/time/time.c +++ b/libc/misc/time/time.c @@ -1835,30 +1835,43 @@ static smallint TZ_file_read; /* Let BSS initialization set this to 0. */ static char *read_TZ_file(char *buf) { int fd; - ssize_t r; - size_t todo; char *p = NULL; - if ((fd = open(__UCLIBC_TZ_FILE_PATH__, O_RDONLY)) >= 0) { - todo = TZ_BUFLEN; + fd = open(__UCLIBC_TZ_FILE_PATH__, O_RDONLY); + if (fd >= 0) { + ssize_t r; +#if 0 + /* TZ are small *files*. On files, short reads + * only occur on EOF (unlike, say, pipes). + * The code below is pedanticallly more correct, + * but this way we always read at least twice: + * 1st read is short, 2nd one is zero bytes. + */ + size_t todo = TZ_BUFLEN; p = buf; do { - if ((r = read(fd, p, todo)) < 0) { + r = read(fd, p, todo); + if (r < 0) goto ERROR; - } - if (r == 0) { + if (r == 0) break; - } p += r; todo -= r; } while (todo); +#else + /* Shorter, and does one less read syscall */ + r = read(fd, buf, TZ_BUFLEN); + if (r < 0) + goto ERROR; + p = buf + r; +#endif - if ((p > buf) && (p[-1] == '\n')) { /* Must end with newline. */ + if ((p > buf) && (p[-1] == '\n')) { /* Must end with newline */ p[-1] = 0; p = buf; #ifndef __UCLIBC_HAS_TZ_FILE_READ_MANY__ TZ_file_read = 1; -#endif /* __UCLIBC_HAS_TZ_FILE_READ_MANY__ */ +#endif } else { ERROR: p = NULL; |