Dear Mike Dunn,
Thanks again Marek. A question below...
On 04/14/2013 10:38 AM, Marek Vasut wrote:
[...]
- if (argc != 3) {
printf("usage: %s <image file> <mtd dev node>\n", argv[0]);exit(-1);Use proper errno and "return" as you're returning from main() anyway.
Agreed regarding 'return'. But should I be concerned with setting or preserving errno before all 'return -1' lines? Is it normal practice for a common utility to set errno? errno will have to be saved in many places, since perror() itself can change it. This will add many more lines of code.
Ooops! errno.h, sorry for the confusion :-(
[...]
- blockbuf = malloc(RELIABLE_BLOCKSIZE);
Do you not want to use some calloc() here to make sure the "blockbuf" is zeroed?
Not necessary here; the buffer is always filled or the utility exits with error. But will change to calloc() anyway.
If you're sure it's filled, then it's no problem.
[...]
/* read data for one block from file */while (len != 0 && (read_ret = read(datafd, buf, len)) != 0) {Uh, this really might be a candidate for IOCCC, split this please ...
Well, OK, but... I normally don't embed calls in tests, but I do it here because the read is performed at the start of each loop iteration, and I thought this made it clearer and more concise. Basically it means "loop while there's still more data to write, and read() does not return EOF".
Actually, read() should never return EOF, because earlier I check the file length, so if I'm going to do the sanity check anyway, maybe it should be separate.
I'd say you can loop and break; out if needed, no ?
while (cond.) { if (x) break; if (y) break;
do_useful_stuff here; }
Best regards, Marek Vasut