Date: Tue, 6 Dec 2016 19:08:29 +0000 (UTC) From: Ed Schouten <ed@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r309650 - head/lib/libc/gen Message-ID: <201612061908.uB6J8TMS025860@repo.freebsd.org>
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Author: ed Date: Tue Dec 6 19:08:29 2016 New Revision: 309650 URL: https://svnweb.freebsd.org/changeset/base/309650 Log: Properly sign extend the result of jrand48() and mrand48(). These functions are supposed to return a value between [_2^31, 2^31). This doesn't seem to work on 64-bit systems, where we return a value between [0, 3^32). Patch up the function to use proper casts to int32_t. While there, fix some other style bugs. MFC after: 2 weeks Modified: head/lib/libc/gen/jrand48.c head/lib/libc/gen/mrand48.c Modified: head/lib/libc/gen/jrand48.c ============================================================================== --- head/lib/libc/gen/jrand48.c Tue Dec 6 18:58:42 2016 (r309649) +++ head/lib/libc/gen/jrand48.c Tue Dec 6 19:08:29 2016 (r309650) @@ -14,11 +14,14 @@ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); +#include <stdint.h> + #include "rand48.h" long jrand48(unsigned short xseed[3]) { + _dorand48(xseed); - return ((long) xseed[2] << 16) + (long) xseed[1]; + return ((int32_t)(((uint32_t)xseed[2] << 16) | (uint32_t)xseed[1])); } Modified: head/lib/libc/gen/mrand48.c ============================================================================== --- head/lib/libc/gen/mrand48.c Tue Dec 6 18:58:42 2016 (r309649) +++ head/lib/libc/gen/mrand48.c Tue Dec 6 19:08:29 2016 (r309650) @@ -14,6 +14,8 @@ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); +#include <stdint.h> + #include "rand48.h" extern unsigned short _rand48_seed[3]; @@ -21,6 +23,8 @@ extern unsigned short _rand48_seed[3]; long mrand48(void) { + _dorand48(_rand48_seed); - return ((long) _rand48_seed[2] << 16) + (long) _rand48_seed[1]; + return ((int32_t)(((uint32_t)_rand48_seed[2] << 16) | + (uint32_t)_rand48_seed[1])); }
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