From ba8920d51c60e1f2bbe50aa9c8504207cf86bf9b Mon Sep 17 00:00:00 2001 From: ache Date: Sun, 22 May 2016 06:18:59 +0000 Subject: 1) POSIX prohibits printing errors to stderr here and require returning NULL: "Upon successful completion, initstate() and setstate() shall return a pointer to the previous state array; otherwise, a null pointer shall be returned. Although some implementations of random() have written messages to standard error, such implementations do not conform to POSIX.1-2008." 2) Move error detections earlier to prevent state modifying. MFC after: 1 week --- lib/libc/stdlib/random.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) (limited to 'lib') diff --git a/lib/libc/stdlib/random.c b/lib/libc/stdlib/random.c index 580f26e3..f7b745e 100644 --- a/lib/libc/stdlib/random.c +++ b/lib/libc/stdlib/random.c @@ -37,7 +37,6 @@ __FBSDID("$FreeBSD$"); #include #include #include -#include #include #include "un-namespace.h" @@ -341,15 +340,12 @@ initstate(unsigned long seed, char *arg_state, long n) char *ostate = (char *)(&state[-1]); uint32_t *int_arg_state = (uint32_t *)arg_state; + if (n < BREAK_0) + return (NULL); if (rand_type == TYPE_0) state[-1] = rand_type; else state[-1] = MAX_TYPES * (rptr - state) + rand_type; - if (n < BREAK_0) { - (void)fprintf(stderr, - "random: not enough state (%ld bytes); ignored.\n", n); - return (0); - } if (n < BREAK_1) { rand_type = TYPE_0; rand_deg = DEG_0; @@ -408,24 +404,23 @@ setstate(char *arg_state) uint32_t rear = new_state[0] / MAX_TYPES; char *ostate = (char *)(&state[-1]); - if (rand_type == TYPE_0) - state[-1] = rand_type; - else - state[-1] = MAX_TYPES * (rptr - state) + rand_type; switch(type) { case TYPE_0: case TYPE_1: case TYPE_2: case TYPE_3: case TYPE_4: - rand_type = type; - rand_deg = degrees[type]; - rand_sep = seps[type]; break; default: - (void)fprintf(stderr, - "random: state info corrupted; not changed.\n"); + return (NULL); } + if (rand_type == TYPE_0) + state[-1] = rand_type; + else + state[-1] = MAX_TYPES * (rptr - state) + rand_type; + rand_type = type; + rand_deg = degrees[type]; + rand_sep = seps[type]; state = new_state + 1; if (rand_type != TYPE_0) { rptr = &state[rear]; -- cgit v1.1