sbase/split.c
FRIGN 93fd817536 Add estrlcat() and estrlcpy()
It has become a common idiom in sbase to check strlcat() and strlcpy()
using

if (strl{cat, cpy}(dst, src, siz) >= siz)
        eprintf("path too long\n");

However, this was not carried out consistently and to this very day,
some tools employed unchecked calls to these functions, effectively
allowing silent truncations to happen, which in turn may lead to
security issues.
To finally put an end to this, the e*-functions detect truncation
automatically and the caller can lean back and enjoy coding without
trouble. :)
2015-03-17 11:24:49 +01:00

135 lines
2.3 KiB
C

/* See LICENSE file for copyright and license details. */
#include <ctype.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "util.h"
static int base = 26, start = 'a';
static int
itostr(char *str, int x, int n)
{
str[n] = '\0';
while (n-- > 0) {
str[n] = start + (x % base);
x /= base;
}
if (x)
return -1;
return 0;
}
static FILE *
nextfile(FILE *f, char *buf, int plen, int slen)
{
static int filecount = 0;
if (f)
fclose(f);
if (itostr(buf + plen, filecount++, slen) < 0)
return NULL;
if (!(f = fopen(buf, "w")))
eprintf("'%s':", buf);
return f;
}
static void
usage(void)
{
eprintf("usage: %s [-a len] [-b bytes[k|m|g]] [-d] [-l lines] "
"[input [prefix]]\n", argv0);
}
int
main(int argc, char *argv[])
{
FILE *in = stdin, *out = NULL;
char name[NAME_MAX + 1];
char *prefix = "x";
char *file = NULL;
char *tmp, *end;
size_t size = 1000, scale = 1, n;
int ch, plen, slen = 2, always = 0;
long l;
ARGBEGIN {
case 'a':
slen = estrtonum(EARGF(usage()), 0, INT_MAX);
break;
case 'b':
always = 1;
tmp = EARGF(usage());
l = strtol(tmp, &end, 10);
if (l <= 0)
eprintf("invalid number of bytes: %s\n", tmp);
size = (size_t)l;
if (!*end)
break;
switch (toupper((int)*end)) {
case 'K':
scale = 1024;
break;
case 'M':
scale = 1024L * 1024L;
break;
case 'G':
scale = 1024L * 1024L * 1024L;
break;
default:
usage();
}
if (size > (SIZE_MAX / scale))
eprintf("'%s': out of range\n", tmp);
size *= scale;
break;
case 'd':
base = 10;
start = '0';
break;
case 'l':
always = 0;
tmp = EARGF(usage());
size = estrtonum(tmp, 1, MIN(LLONG_MAX, SIZE_MAX));
break;
default:
usage();
} ARGEND;
if (*argv)
file = *argv++;
if (*argv)
prefix = *argv++;
if (*argv)
usage();
plen = strlen(prefix);
if (plen + slen > NAME_MAX)
eprintf("names cannot exceed %d bytes\n", NAME_MAX);
estrlcpy(name, prefix, sizeof(name));
if (file && strcmp(file, "-") != 0) {
if (!(in = fopen(file, "r")))
eprintf("'%s':", file);
}
n = 0;
while ((ch = getc(in)) != EOF) {
if (!out || n >= size) {
if (!(out = nextfile(out, name, plen, slen)))
eprintf("fopen: %s:", name);
n = 0;
}
n += (always || ch == '\n');
putc(ch, out);
}
if (in != stdin)
fclose(in);
if (out)
fclose(out);
return 0;
}