xfstests, weird looking code in src/resvtest.c

scameron
2014-06-17T16:21:44Z

This code in xfstests src/resvtest.c looks pretty strange:

...
32 char *readbuffer, *writebuffer;
...
70 readbuffer = memalign(psize, bsize);
71 writebuffer = memalign(psize, bsize);
72 if (!readbuffer || !writebuffer) {
73 perror("open");
74 exit(1);
75 }
76 memset(writebuffer, 'A', sizeof(writebuffer));

^^^ writebuffer is a pointer, so using sizeof(writebuffer) here is
odd. Is it intentional to put either 4 or 8 A's into writebuffer
depending on sizeof a pointer? Seems unlikely.

110 while (++n < iterations) {
111 char *p;
112 int numerrors;
113
114 if (write(writefd, writebuffer, sizeof(writebuffer)) < 0) {
115 perror("write");
116 exit(1);
117 }

So that write will write sizeof a pointer's worth of whatever's in writebuffer.
Intentional? Again, seems unlikely.

This seems like maybe somebody initially declared writebuffer as an array, but
later went back and changed it to a pointer, but forgot to fixup everywhere that
referred to sizeof(writebuffer).

I would have sent a patch but I'm not sure what this code is trying to do.

gcc 4.4.7 (what comes with RHEL6u5) doesn't warn about this, but 4.8.3 does.

-- steve

_______________________________________________
xfs mailing list
xfs@oss.sgi.com