Re: [PATCH] mailsplit and mailinfo: gracefully handle NUL characters
two quibbles of no great importance ...
Johannes Schindelin suggested:
Show 5 quoted lines
> The function fgets() has a big problem with NUL characters: it reads
> them, but nobody will know if the NUL comes from the file stream, or
> was appended at the end of the line.
>
> So implement a custom read_line() function.
^^^^^^^^^^^
read_line_with_nul()
meaning read part or all of one line which may contain NULs.Show 26 quoted lines
>[ ... ]
> diff --git a/builtin-mailsplit.c b/builtin-mailsplit.c
> index 46b27cd..021dc16 100644
> --- a/builtin-mailsplit.c
> +++ b/builtin-mailsplit.c
> @@ -45,6 +45,25 @@ static int is_from_line(const char *line, int len)
> /* Could be as small as 64, enough to hold a Unix "From " line. */
> static char buf[4096];
>
> +/* We cannot use fgets() because our lines can contain NULs */
> +int read_line_with_nul(char *buf, int size, FILE *in)
> +{
> + int len = 0, c;
> +
> + for (;;) {
> + c = fgetc(in);
> + buf[len++] = c;
> + if (c == EOF || c == '\n' || len + 1 >= size)
> + break;
> + }
> +
> + if (c == EOF)
> + len--;
> + buf[len] = '\0';
> +
> + return len; when fgetc(3) — why not use getc(3)? — returns EOF
it is pointlessly stored in buf[] (as a 'char'!),
len's advanced, and then the storage and advancing
are undone. isn't that a bit silly? untested:
assert(2 <= size);
do {
if ((c = getc(in)) == EOF)
break;
} while (((buf[len++] = c) != '\n' && len+1 < size);
buf[len] = '\0' return len;
I'd tend to write this in terms of pointers,
something along the lines (untested):
char *p, *endp;
assert(1 <= size);
p = buf;
endp = p + (size-1);
while (p < endp) {
if ((c = getc(in)) == EOF || (*p++ = c) == '\n')
break;
}
*p = '\0'; return p - buf;
> +
> +}
--
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