1// SPDX-License-Identifier: GPL-2.0
 2#include <errno.h>
 3#include <stdlib.h>
 4#include "strbuf.h"
 5#include "quote.h"
 6#include "util.h"
 7
 8/* Help to copy the thing properly quoted for the shell safety.
 9 * any single quote is replaced with '\'', any exclamation point
10 * is replaced with '\!', and the whole thing is enclosed in a
11 *
12 * E.g.
13 *  original     sq_quote     result
14 *  name     ==> name      ==> 'name'
15 *  a b      ==> a b       ==> 'a b'
16 *  a'b      ==> a'\''b    ==> 'a'\''b'
17 *  a!b      ==> a'\!'b    ==> 'a'\!'b'
18 */
19static inline int need_bs_quote(char c)
20{
21	return (c == '\'' || c == '!');
22}
23
24static int sq_quote_buf(struct strbuf *dst, const char *src)
25{
26	char *to_free = NULL;
27	int ret;
28
29	if (dst->buf == src)
30		to_free = strbuf_detach(dst, NULL);
31
32	ret = strbuf_addch(dst, '\'');
33	while (!ret && *src) {
34		size_t len = strcspn(src, "'!");
35		ret = strbuf_add(dst, src, len);
36		src += len;
37		while (!ret && need_bs_quote(*src))
38			ret = strbuf_addf(dst, "'\\%c\'", *src++);
39	}
40	if (!ret)
41		ret = strbuf_addch(dst, '\'');
42	free(to_free);
43
44	return ret;
45}
46
47int sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
48{
49	int i, ret;
50
51	/* Copy into destination buffer. */
52	ret = strbuf_grow(dst, 255);
53	for (i = 0; !ret && argv[i]; ++i) {
54		ret = strbuf_addch(dst, ' ');
55		if (ret)
56			break;
57		ret = sq_quote_buf(dst, argv[i]);
58		if (maxlen && dst->len > maxlen)
59			return -ENOSPC;
60	}
61	return ret;
62}