[thirdparty/git.git] / quote.c

#include "cache.h"
#include "quote.h"

int quote_path_fully = 1;

/* Help to copy the thing properly quoted for the shell safety.
 * any single quote is replaced with '\'', any exclamation point
 * is replaced with '\!', and the whole thing is enclosed in a
 *
 * E.g.
 *  original     sq_quote     result
 *  name     ==> name      ==> 'name'
 *  a b      ==> a b       ==> 'a b'
 *  a'b      ==> a'\''b    ==> 'a'\''b'
 *  a!b      ==> a'\!'b    ==> 'a'\!'b'
 */
static inline int need_bs_quote(char c)
{
	return (c == '\'' || c == '!');
}

void sq_quote_buf(struct strbuf *dst, const char *src)
{
	char *to_free = NULL;

	if (dst->buf == src)
		to_free = strbuf_detach(dst, NULL);

	strbuf_addch(dst, '\'');
	while (*src) {
		size_t len = strcspn(src, "'!");
		strbuf_add(dst, src, len);
		src += len;
		while (need_bs_quote(*src)) {
			strbuf_addstr(dst, "'\\");
			strbuf_addch(dst, *src++);
			strbuf_addch(dst, '\'');
		}
	}
	strbuf_addch(dst, '\'');
	free(to_free);
}

void sq_quote_print(FILE *stream, const char *src)
{
	char c;

	fputc('\'', stream);
	while ((c = *src++)) {
		if (need_bs_quote(c)) {
			fputs("'\\", stream);
			fputc(c, stream);
			fputc('\'', stream);
		} else {
			fputc(c, stream);
		}
	}
	fputc('\'', stream);
}

void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
{
	int i;

	/* Copy into destination buffer. */
	strbuf_grow(dst, 255);
	for (i = 0; argv[i]; ++i) {
		strbuf_addch(dst, ' ');
		sq_quote_buf(dst, argv[i]);
		if (maxlen && dst->len > maxlen)
			die("Too many or long arguments");
	}
}

char *sq_dequote_step(char *arg, char **next)
{
	char *dst = arg;
	char *src = arg;
	char c;

	if (*src != '\'')
		return NULL;
	for (;;) {
		c = *++src;
		if (!c)
			return NULL;
		if (c != '\'') {
			*dst++ = c;
			continue;
		}
		/* We stepped out of sq */
		switch (*++src) {
		case '\0':
			*dst = 0;
			if (next)
				*next = NULL;
			return arg;
		case '\\':
			c = *++src;
			if (need_bs_quote(c) && *++src == '\'') {
				*dst++ = c;
				continue;
			}
		/* Fallthrough */
		default:
			if (!next || !isspace(*src))
				return NULL;
			do {
				c = *++src;
			} while (isspace(c));
			*dst = 0;
			*next = src;
			return arg;
		}
	}
}

char *sq_dequote(char *arg)
{
	return sq_dequote_step(arg, NULL);
}

int sq_dequote_to_argv(char *arg, const char ***argv, int *nr, int *alloc)
{
	char *next = arg;

	if (!*arg)
		return 0;
	do {
		char *dequoted = sq_dequote_step(next, &next);
		if (!dequoted)
			return -1;
		ALLOC_GROW(*argv, *nr + 1, *alloc);
		(*argv)[(*nr)++] = dequoted;
	} while (next);

	return 0;
}

/* 1 means: quote as octal
 * 0 means: quote as octal if (quote_path_fully)
 * -1 means: never quote
 * c: quote as "\\c"
 */
#define X8(x)   x, x, x, x, x, x, x, x
#define X16(x)  X8(x), X8(x)
static signed char const sq_lookup[256] = {
	/*           0    1    2    3    4    5    6    7 */
	/* 0x00 */   1,   1,   1,   1,   1,   1,   1, 'a',
	/* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r',   1,   1,
	/* 0x10 */ X16(1),
	/* 0x20 */  -1,  -1, '"',  -1,  -1,  -1,  -1,  -1,
	/* 0x28 */ X16(-1), X16(-1), X16(-1),
	/* 0x58 */  -1,  -1,  -1,  -1,'\\',  -1,  -1,  -1,
	/* 0x60 */ X16(-1), X8(-1),
	/* 0x78 */  -1,  -1,  -1,  -1,  -1,  -1,  -1,   1,
	/* 0x80 */ /* set to 0 */
};

static inline int sq_must_quote(char c)
{
	return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
}

/* returns the longest prefix not needing a quote up to maxlen if positive.
   This stops at the first \0 because it's marked as a character needing an
   escape */
static size_t next_quote_pos(const char *s, ssize_t maxlen)
{
	size_t len;
	if (maxlen < 0) {
		for (len = 0; !sq_must_quote(s[len]); len++);
	} else {
		for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
	}
	return len;
}

/*
 * C-style name quoting.
 *
 * (1) if sb and fp are both NULL, inspect the input name and counts the
 *     number of bytes that are needed to hold c_style quoted version of name,
 *     counting the double quotes around it but not terminating NUL, and
 *     returns it.
 *     However, if name does not need c_style quoting, it returns 0.
 *
 * (2) if sb or fp are not NULL, it emits the c_style quoted version
 *     of name, enclosed with double quotes if asked and needed only.
 *     Return value is the same as in (1).
 */
static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
                                    struct strbuf *sb, FILE *fp, int no_dq)
{
#undef EMIT
#define EMIT(c)                                 \
	do {                                        \
		if (sb) strbuf_addch(sb, (c));          \
		if (fp) fputc((c), fp);                 \
		count++;                                \
	} while (0)
#define EMITBUF(s, l)                           \
	do {                                        \
		if (sb) strbuf_add(sb, (s), (l));       \
		if (fp) fwrite((s), (l), 1, fp);        \
		count += (l);                           \
	} while (0)

	size_t len, count = 0;
	const char *p = name;

	for (;;) {
		int ch;

		len = next_quote_pos(p, maxlen);
		if (len == maxlen || !p[len])
			break;

		if (!no_dq && p == name)
			EMIT('"');

		EMITBUF(p, len);
		EMIT('\\');
		p += len;
		ch = (unsigned char)*p++;
		if (sq_lookup[ch] >= ' ') {
			EMIT(sq_lookup[ch]);
		} else {
			EMIT(((ch >> 6) & 03) + '0');
			EMIT(((ch >> 3) & 07) + '0');
			EMIT(((ch >> 0) & 07) + '0');
		}
	}

	EMITBUF(p, len);
	if (p == name)   /* no ending quote needed */
		return 0;

	if (!no_dq)
		EMIT('"');
	return count;
}

size_t quote_c_style(const char *name, struct strbuf *sb, FILE *fp, int nodq)
{
	return quote_c_style_counted(name, -1, sb, fp, nodq);
}

void quote_two_c_style(struct strbuf *sb, const char *prefix, const char *path, int nodq)
{
	if (quote_c_style(prefix, NULL, NULL, 0) ||
	    quote_c_style(path, NULL, NULL, 0)) {
		if (!nodq)
			strbuf_addch(sb, '"');
		quote_c_style(prefix, sb, NULL, 1);
		quote_c_style(path, sb, NULL, 1);
		if (!nodq)
			strbuf_addch(sb, '"');
	} else {
		strbuf_addstr(sb, prefix);
		strbuf_addstr(sb, path);
	}
}

void write_name_quoted(const char *name, FILE *fp, int terminator)
{
	if (terminator) {
		quote_c_style(name, NULL, fp, 0);
	} else {
		fputs(name, fp);
	}
	fputc(terminator, fp);
}

void write_name_quotedpfx(const char *pfx, size_t pfxlen,
			  const char *name, FILE *fp, int terminator)
{
	int needquote = 0;

	if (terminator) {
		needquote = next_quote_pos(pfx, pfxlen) < pfxlen
			|| name[next_quote_pos(name, -1)];
	}
	if (needquote) {
		fputc('"', fp);
		quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
		quote_c_style(name, NULL, fp, 1);
		fputc('"', fp);
	} else {
		fwrite(pfx, pfxlen, 1, fp);
		fputs(name, fp);
	}
	fputc(terminator, fp);
}

/* quote path as relative to the given prefix */
char *quote_path_relative(const char *in, int len,
			  struct strbuf *out, const char *prefix)
{
	int needquote;

	if (len < 0)
		len = strlen(in);

	/* "../" prefix itself does not need quoting, but "in" might. */
	needquote = next_quote_pos(in, len) < len;
	strbuf_setlen(out, 0);
	strbuf_grow(out, len);

	if (needquote)
		strbuf_addch(out, '"');
	if (prefix) {
		int off = 0;
		while (prefix[off] && off < len && prefix[off] == in[off])
			if (prefix[off] == '/') {
				prefix += off + 1;
				in += off + 1;
				len -= off + 1;
				off = 0;
			} else
				off++;

		for (; *prefix; prefix++)
			if (*prefix == '/')
				strbuf_addstr(out, "../");
	}

	quote_c_style_counted (in, len, out, NULL, 1);

	if (needquote)
		strbuf_addch(out, '"');
	if (!out->len)
		strbuf_addstr(out, "./");

	return out->buf;
}

/*
 * C-style name unquoting.
 *
 * Quoted should point at the opening double quote.
 * + Returns 0 if it was able to unquote the string properly, and appends the
 *   result in the strbuf `sb'.
 * + Returns -1 in case of error, and doesn't touch the strbuf. Though note
 *   that this function will allocate memory in the strbuf, so calling
 *   strbuf_release is mandatory whichever result unquote_c_style returns.
 *
 * Updates endp pointer to point at one past the ending double quote if given.
 */
int unquote_c_style(struct strbuf *sb, const char *quoted, const char **endp)
{
	size_t oldlen = sb->len, len;
	int ch, ac;

	if (*quoted++ != '"')
		return -1;

	for (;;) {
		len = strcspn(quoted, "\"\\");
		strbuf_add(sb, quoted, len);
		quoted += len;

		switch (*quoted++) {
		  case '"':
			if (endp)
				*endp = quoted;
			return 0;
		  case '\\':
			break;
		  default:
			goto error;
		}

		switch ((ch = *quoted++)) {
		case 'a': ch = '\a'; break;
		case 'b': ch = '\b'; break;
		case 'f': ch = '\f'; break;
		case 'n': ch = '\n'; break;
		case 'r': ch = '\r'; break;
		case 't': ch = '\t'; break;
		case 'v': ch = '\v'; break;

		case '\\': case '"':
			break; /* verbatim */

		/* octal values with first digit over 4 overflow */
		case '0': case '1': case '2': case '3':
					ac = ((ch - '0') << 6);
			if ((ch = *quoted++) < '0' || '7' < ch)
				goto error;
					ac |= ((ch - '0') << 3);
			if ((ch = *quoted++) < '0' || '7' < ch)
				goto error;
					ac |= (ch - '0');
					ch = ac;
					break;
				default:
			goto error;
			}
		strbuf_addch(sb, ch);
		}

  error:
	strbuf_setlen(sb, oldlen);
	return -1;
}

/* quoting as a string literal for other languages */

void perl_quote_print(FILE *stream, const char *src)
{
	const char sq = '\'';
	const char bq = '\\';
	char c;

	fputc(sq, stream);
	while ((c = *src++)) {
		if (c == sq || c == bq)
			fputc(bq, stream);
		fputc(c, stream);
	}
	fputc(sq, stream);
}

void python_quote_print(FILE *stream, const char *src)
{
	const char sq = '\'';
	const char bq = '\\';
	const char nl = '\n';
	char c;

	fputc(sq, stream);
	while ((c = *src++)) {
		if (c == nl) {
			fputc(bq, stream);
			fputc('n', stream);
			continue;
		}
		if (c == sq || c == bq)
			fputc(bq, stream);
		fputc(c, stream);
	}
	fputc(sq, stream);
}

void tcl_quote_print(FILE *stream, const char *src)
{
	char c;

	fputc('"', stream);
	while ((c = *src++)) {
		switch (c) {
		case '[': case ']':
		case '{': case '}':
		case '$': case '\\': case '"':
			fputc('\\', stream);
		default:
			fputc(c, stream);
			break;
		case '\f':
			fputs("\\f", stream);
			break;
		case '\r':
			fputs("\\r", stream);
			break;
		case '\n':
			fputs("\\n", stream);
			break;
		case '\t':
			fputs("\\t", stream);
			break;
		case '\v':
			fputs("\\v", stream);
			break;
		}
	}
	fputc('"', stream);
}
Commit	Line	Data
6fb737be JH	1	#include "cache.h"
	2	#include "quote.h"
	3
5b8e6f85 DP	4	int quote_path_fully = 1;
5b8e6f85 DP	5
6fb737be	6	/* Help to copy the thing properly quoted for the shell safety.
77d604c3 PA	7	* any single quote is replaced with '\'', any exclamation point
77d604c3 PA	8	* is replaced with '\!', and the whole thing is enclosed in a
6fb737be JH	9	*
	10	* E.g.
	11	* original sq_quote result
	12	* name ==> name ==> 'name'
	13	* a b ==> a b ==> 'a b'
	14	* a'b ==> a'\''b ==> 'a'\''b'
77d604c3	15	* a!b ==> a'\!'b ==> 'a'\!'b'
6fb737be	16	*/
35eb2d36 LT	17	static inline int need_bs_quote(char c)
	18	{
	19	return (c == '\'' \|\| c == '!');
	20	}
	21
7a33bcbe	22	void sq_quote_buf(struct strbuf dst, const char src)
77d604c3	23	{
7a33bcbe PH	24	char *to_free = NULL;
	25
	26	if (dst->buf == src)
b315c5c0	27	to_free = strbuf_detach(dst, NULL);
7a33bcbe PH	28
	29	strbuf_addch(dst, '\'');
	30	while (*src) {
c2015b3a	31	size_t len = strcspn(src, "'!");
7a33bcbe PH	32	strbuf_add(dst, src, len);
	33	src += len;
	34	while (need_bs_quote(*src)) {
	35	strbuf_addstr(dst, "'\\");
	36	strbuf_addch(dst, *src++);
	37	strbuf_addch(dst, '\'');
6fb737be JH	38	}
6fb737be JH	39	}
7a33bcbe PH	40	strbuf_addch(dst, '\'');
7a33bcbe PH	41	free(to_free);
77d604c3 PA	42	}
77d604c3 PA	43
575ba9d6 ML	44	void sq_quote_print(FILE stream, const char src)
	45	{
	46	char c;
	47
	48	fputc('\'', stream);
	49	while ((c = *src++)) {
	50	if (need_bs_quote(c)) {
	51	fputs("'\\", stream);
	52	fputc(c, stream);
	53	fputc('\'', stream);
	54	} else {
	55	fputc(c, stream);
	56	}
	57	}
	58	fputc('\'', stream);
	59	}
	60
b319ce4c	61	void sq_quote_argv(struct strbuf dst, const char* argv, size_t maxlen)
7cf67205	62	{
7cf67205	63	int i;
7cf67205	64
7cf67205	65	/* Copy into destination buffer. */
b319ce4c CC	66	strbuf_grow(dst, 255);
b319ce4c CC	67	for (i = 0; argv[i]; ++i) {
7a33bcbe PH	68	strbuf_addch(dst, ' ');
	69	sq_quote_buf(dst, argv[i]);
	70	if (maxlen && dst->len > maxlen)
	71	die("Too many or long arguments");
7cf67205	72	}
86257aa3 CC	73	}
86257aa3 CC	74
ebbc088e	75	char sq_dequote_step(char arg, char **next)
35eb2d36 LT	76	{
	77	char *dst = arg;
	78	char *src = arg;
	79	char c;
	80
	81	if (*src != '\'')
	82	return NULL;
	83	for (;;) {
	84	c = *++src;
	85	if (!c)
	86	return NULL;
	87	if (c != '\'') {
	88	*dst++ = c;
	89	continue;
	90	}
	91	/* We stepped out of sq */
	92	switch (*++src) {
	93	case '\0':
	94	*dst = 0;
ebbc088e CC	95	if (next)
ebbc088e CC	96	*next = NULL;
35eb2d36 LT	97	return arg;
	98	case '\\':
	99	c = *++src;
	100	if (need_bs_quote(c) && *++src == '\'') {
	101	*dst++ = c;
	102	continue;
	103	}
	104	/* Fallthrough */
	105	default:
ebbc088e CC	106	if (!next \|\| !isspace(*src))
	107	return NULL;
	108	do {
	109	c = *++src;
	110	} while (isspace(c));
	111	*dst = 0;
	112	*next = src;
	113	return arg;
35eb2d36 LT	114	}
	115	}
	116	}
	117
ebbc088e CC	118	char sq_dequote(char arg)
	119	{
	120	return sq_dequote_step(arg, NULL);
	121	}
	122
eaa759b9 CC	123	int sq_dequote_to_argv(char arg, const char *argv, int nr, int *alloc)
	124	{
	125	char *next = arg;
	126
	127	if (!*arg)
	128	return 0;
	129	do {
	130	char *dequoted = sq_dequote_step(next, &next);
	131	if (!dequoted)
	132	return -1;
	133	ALLOC_GROW(argv, nr + 1, *alloc);
	134	(argv)[(nr)++] = dequoted;
	135	} while (next);
	136
	137	return 0;
	138	}
	139
663af342 PH	140	/* 1 means: quote as octal
	141	* 0 means: quote as octal if (quote_path_fully)
	142	* -1 means: never quote
	143	* c: quote as "\\c"
	144	*/
	145	#define X8(x) x, x, x, x, x, x, x, x
	146	#define X16(x) X8(x), X8(x)
	147	static signed char const sq_lookup[256] = {
	148	/* 0 1 2 3 4 5 6 7 */
	149	/* 0x00 */ 1, 1, 1, 1, 1, 1, 1, 'a',
	150	/* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r', 1, 1,
	151	/* 0x10 */ X16(1),
	152	/* 0x20 */ -1, -1, '"', -1, -1, -1, -1, -1,
	153	/* 0x28 */ X16(-1), X16(-1), X16(-1),
	154	/* 0x58 */ -1, -1, -1, -1,'\\', -1, -1, -1,
	155	/* 0x60 */ X16(-1), X8(-1),
	156	/* 0x78 */ -1, -1, -1, -1, -1, -1, -1, 1,
	157	/* 0x80 / / set to 0 */
	158	};
	159
f3fa1838 JH	160	static inline int sq_must_quote(char c)
f3fa1838 JH	161	{
663af342 PH	162	return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
	163	}
	164
	165	/* returns the longest prefix not needing a quote up to maxlen if positive.
	166	This stops at the first \0 because it's marked as a character needing an
	167	escape */
	168	static size_t next_quote_pos(const char *s, ssize_t maxlen)
	169	{
	170	size_t len;
	171	if (maxlen < 0) {
	172	for (len = 0; !sq_must_quote(s[len]); len++);
	173	} else {
	174	for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
	175	}
	176	return len;
	177	}
	178
4f6fbcdc JH	179	/*
	180	* C-style name quoting.
	181	*
663af342 PH	182	* (1) if sb and fp are both NULL, inspect the input name and counts the
	183	* number of bytes that are needed to hold c_style quoted version of name,
	184	* counting the double quotes around it but not terminating NUL, and
	185	* returns it.
	186	* However, if name does not need c_style quoting, it returns 0.
4f6fbcdc	187	*
663af342 PH	188	* (2) if sb or fp are not NULL, it emits the c_style quoted version
	189	* of name, enclosed with double quotes if asked and needed only.
	190	* Return value is the same as in (1).
4f6fbcdc	191	*/
663af342 PH	192	static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
663af342 PH	193	struct strbuf sb, FILE fp, int no_dq)
4f6fbcdc JH	194	{
4f6fbcdc JH	195	#undef EMIT
663af342 PH	196	#define EMIT(c) \
	197	do { \
	198	if (sb) strbuf_addch(sb, (c)); \
	199	if (fp) fputc((c), fp); \
	200	count++; \
	201	} while (0)
	202	#define EMITBUF(s, l) \
	203	do { \
	204	if (sb) strbuf_add(sb, (s), (l)); \
	205	if (fp) fwrite((s), (l), 1, fp); \
	206	count += (l); \
	207	} while (0)
	208
	209	size_t len, count = 0;
	210	const char *p = name;
4f6fbcdc	211
663af342 PH	212	for (;;) {
663af342 PH	213	int ch;
4f6fbcdc	214
663af342 PH	215	len = next_quote_pos(p, maxlen);
663af342 PH	216	if (len == maxlen \|\| !p[len])
50e7b067	217	break;
663af342 PH	218
	219	if (!no_dq && p == name)
	220	EMIT('"');
	221
	222	EMITBUF(p, len);
	223	EMIT('\\');
	224	p += len;
	225	ch = (unsigned char)*p++;
	226	if (sq_lookup[ch] >= ' ') {
	227	EMIT(sq_lookup[ch]);
	228	} else {
	229	EMIT(((ch >> 6) & 03) + '0');
	230	EMIT(((ch >> 3) & 07) + '0');
	231	EMIT(((ch >> 0) & 07) + '0');
4f6fbcdc	232	}
4f6fbcdc	233	}
663af342 PH	234
	235	EMITBUF(p, len);
	236	if (p == name) /* no ending quote needed */
	237	return 0;
	238
4f6fbcdc JH	239	if (!no_dq)
4f6fbcdc JH	240	EMIT('"');
663af342 PH	241	return count;
663af342 PH	242	}
4f6fbcdc	243
663af342 PH	244	size_t quote_c_style(const char name, struct strbuf sb, FILE *fp, int nodq)
	245	{
	246	return quote_c_style_counted(name, -1, sb, fp, nodq);
4f6fbcdc JH	247	}
4f6fbcdc JH	248
d5625091 JH	249	void quote_two_c_style(struct strbuf sb, const char prefix, const char *path, int nodq)
	250	{
	251	if (quote_c_style(prefix, NULL, NULL, 0) \|\|
	252	quote_c_style(path, NULL, NULL, 0)) {
	253	if (!nodq)
	254	strbuf_addch(sb, '"');
	255	quote_c_style(prefix, sb, NULL, 1);
	256	quote_c_style(path, sb, NULL, 1);
	257	if (!nodq)
	258	strbuf_addch(sb, '"');
	259	} else {
	260	strbuf_addstr(sb, prefix);
	261	strbuf_addstr(sb, path);
	262	}
	263	}
	264
663af342	265	void write_name_quoted(const char name, FILE fp, int terminator)
9ef2b3cb	266	{
663af342 PH	267	if (terminator) {
	268	quote_c_style(name, NULL, fp, 0);
	269	} else {
	270	fputs(name, fp);
	271	}
	272	fputc(terminator, fp);
	273	}
	274
2af202be LT	275	void write_name_quotedpfx(const char *pfx, size_t pfxlen,
2af202be LT	276	const char name, FILE fp, int terminator)
663af342 PH	277	{
	278	int needquote = 0;
	279
	280	if (terminator) {
	281	needquote = next_quote_pos(pfx, pfxlen) < pfxlen
	282	\|\| name[next_quote_pos(name, -1)];
	283	}
	284	if (needquote) {
	285	fputc('"', fp);
	286	quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
	287	quote_c_style(name, NULL, fp, 1);
	288	fputc('"', fp);
	289	} else {
	290	fwrite(pfx, pfxlen, 1, fp);
	291	fputs(name, fp);
	292	}
	293	fputc(terminator, fp);
9ef2b3cb JH	294	}
9ef2b3cb JH	295
a734d0b1 DP	296	/* quote path as relative to the given prefix */
	297	char quote_path_relative(const char in, int len,
	298	struct strbuf out, const char prefix)
	299	{
	300	int needquote;
	301
	302	if (len < 0)
	303	len = strlen(in);
	304
	305	/* "../" prefix itself does not need quoting, but "in" might. */
	306	needquote = next_quote_pos(in, len) < len;
	307	strbuf_setlen(out, 0);
	308	strbuf_grow(out, len);
	309
	310	if (needquote)
	311	strbuf_addch(out, '"');
	312	if (prefix) {
	313	int off = 0;
	314	while (prefix[off] && off < len && prefix[off] == in[off])
	315	if (prefix[off] == '/') {
	316	prefix += off + 1;
	317	in += off + 1;
	318	len -= off + 1;
	319	off = 0;
	320	} else
	321	off++;
	322
	323	for (; *prefix; prefix++)
	324	if (*prefix == '/')
	325	strbuf_addstr(out, "../");
	326	}
	327
	328	quote_c_style_counted (in, len, out, NULL, 1);
	329
	330	if (needquote)
	331	strbuf_addch(out, '"');
	332	if (!out->len)
	333	strbuf_addstr(out, "./");
	334
	335	return out->buf;
	336	}
	337
4f6fbcdc JH	338	/*
	339	* C-style name unquoting.
	340	*
7fb1011e PH	341	* Quoted should point at the opening double quote.
	342	* + Returns 0 if it was able to unquote the string properly, and appends the
	343	* result in the strbuf `sb'.
	344	* + Returns -1 in case of error, and doesn't touch the strbuf. Though note
	345	* that this function will allocate memory in the strbuf, so calling
	346	* strbuf_release is mandatory whichever result unquote_c_style returns.
	347	*
	348	* Updates endp pointer to point at one past the ending double quote if given.
4f6fbcdc	349	*/
7fb1011e	350	int unquote_c_style(struct strbuf sb, const char quoted, const char **endp)
4f6fbcdc	351	{
7fb1011e PH	352	size_t oldlen = sb->len, len;
7fb1011e PH	353	int ch, ac;
4f6fbcdc JH	354
4f6fbcdc JH	355	if (*quoted++ != '"')
7fb1011e PH	356	return -1;
	357
	358	for (;;) {
	359	len = strcspn(quoted, "\"\\");
	360	strbuf_add(sb, quoted, len);
	361	quoted += len;
4f6fbcdc	362
7fb1011e PH	363	switch (*quoted++) {
	364	case '"':
	365	if (endp)
c8744d6a	366	*endp = quoted;
7fb1011e PH	367	return 0;
	368	case '\\':
	369	break;
	370	default:
	371	goto error;
	372	}
	373
	374	switch ((ch = *quoted++)) {
	375	case 'a': ch = '\a'; break;
	376	case 'b': ch = '\b'; break;
	377	case 'f': ch = '\f'; break;
	378	case 'n': ch = '\n'; break;
	379	case 'r': ch = '\r'; break;
	380	case 't': ch = '\t'; break;
	381	case 'v': ch = '\v'; break;
	382
	383	case '\\': case '"':
	384	break; /* verbatim */
	385
	386	/* octal values with first digit over 4 overflow */
	387	case '0': case '1': case '2': case '3':
4f6fbcdc	388	ac = ((ch - '0') << 6);
7fb1011e PH	389	if ((ch = *quoted++) < '0' \|\| '7' < ch)
7fb1011e PH	390	goto error;
4f6fbcdc	391	ac \|= ((ch - '0') << 3);
7fb1011e PH	392	if ((ch = *quoted++) < '0' \|\| '7' < ch)
7fb1011e PH	393	goto error;
4f6fbcdc JH	394	ac \|= (ch - '0');
	395	ch = ac;
	396	break;
	397	default:
7fb1011e	398	goto error;
4f6fbcdc	399	}
7fb1011e	400	strbuf_addch(sb, ch);
4f6fbcdc JH	401	}
4f6fbcdc JH	402
7fb1011e PH	403	error:
	404	strbuf_setlen(sb, oldlen);
	405	return -1;
4f6fbcdc JH	406	}
4f6fbcdc JH	407
9f613ddd JH	408	/* quoting as a string literal for other languages */
	409
	410	void perl_quote_print(FILE stream, const char src)
	411	{
	412	const char sq = '\'';
	413	const char bq = '\\';
	414	char c;
	415
	416	fputc(sq, stream);
	417	while ((c = *src++)) {
	418	if (c == sq \|\| c == bq)
	419	fputc(bq, stream);
	420	fputc(c, stream);
	421	}
	422	fputc(sq, stream);
	423	}
	424
	425	void python_quote_print(FILE stream, const char src)
	426	{
	427	const char sq = '\'';
	428	const char bq = '\\';
	429	const char nl = '\n';
	430	char c;
	431
	432	fputc(sq, stream);
	433	while ((c = *src++)) {
	434	if (c == nl) {
	435	fputc(bq, stream);
	436	fputc('n', stream);
	437	continue;
	438	}
	439	if (c == sq \|\| c == bq)
	440	fputc(bq, stream);
	441	fputc(c, stream);
	442	}
	443	fputc(sq, stream);
	444	}
5558e55c SP	445
	446	void tcl_quote_print(FILE stream, const char src)
	447	{
	448	char c;
	449
	450	fputc('"', stream);
	451	while ((c = *src++)) {
	452	switch (c) {
	453	case '[': case ']':
	454	case '{': case '}':
	455	case '$': case '\\': case '"':
	456	fputc('\\', stream);
	457	default:
	458	fputc(c, stream);
	459	break;
	460	case '\f':
	461	fputs("\\f", stream);
	462	break;
	463	case '\r':
	464	fputs("\\r", stream);
	465	break;
	466	case '\n':
	467	fputs("\\n", stream);
	468	break;
	469	case '\t':
	470	fputs("\\t", stream);
	471	break;
	472	case '\v':
	473	fputs("\\v", stream);
	474	break;
	475	}
	476	}
	477	fputc('"', stream);
	478	}