[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");
	}
}

static 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 || (maxlen < 0 && !p[len]))
			break;

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

		EMITBUF(p, len);
		EMIT('\\');
		p += len;
		ch = (unsigned char)*p++;
		if (maxlen >= 0)
			maxlen -= len + 1;
		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);
}

static const char *path_relative(const char *in, int len,
				 struct strbuf *sb, const char *prefix,
				 int prefix_len);

void write_name_quoted_relative(const char *name, size_t len,
				const char *prefix, size_t prefix_len,
				FILE *fp, int terminator)
{
	struct strbuf sb = STRBUF_INIT;

	name = path_relative(name, len, &sb, prefix, prefix_len);
	write_name_quoted(name, fp, terminator);

	strbuf_release(&sb);
}

/*
 * Give path as relative to prefix.
 *
 * The strbuf may or may not be used, so do not assume it contains the
 * returned path.
 */
static const char *path_relative(const char *in, int len,
				 struct strbuf *sb, const char *prefix,
				 int prefix_len)
{
	int off, i;

	if (len < 0)
		len = strlen(in);
	if (prefix && prefix_len < 0)
		prefix_len = strlen(prefix);

	off = 0;
	i = 0;
	while (i < prefix_len && i < len && prefix[i] == in[i]) {
		if (prefix[i] == '/')
			off = i + 1;
		i++;
	}
	in += off;
	len -= off;

	if (i >= prefix_len)
		return in;

	strbuf_reset(sb);
	strbuf_grow(sb, len);

	while (i < prefix_len) {
		if (prefix[i] == '/')
			strbuf_addstr(sb, "../");
		i++;
	}
	strbuf_add(sb, in, len);

	return sb->buf;
}

/* quote path as relative to the given prefix */
char *quote_path_relative(const char *in, int len,
			  struct strbuf *out, const char *prefix)
{
	struct strbuf sb = STRBUF_INIT;
	const char *rel = path_relative(in, len, &sb, prefix, -1);
	strbuf_reset(out);
	quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
	strbuf_release(&sb);

	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
758e915b	75	static 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	215	len = next_quote_pos(p, maxlen);
84249819	216	if (len == maxlen \|\| (maxlen < 0 && !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++;
84249819 JK	226	if (maxlen >= 0)
84249819 JK	227	maxlen -= len + 1;
663af342 PH	228	if (sq_lookup[ch] >= ' ') {
	229	EMIT(sq_lookup[ch]);
	230	} else {
	231	EMIT(((ch >> 6) & 03) + '0');
	232	EMIT(((ch >> 3) & 07) + '0');
	233	EMIT(((ch >> 0) & 07) + '0');
4f6fbcdc	234	}
4f6fbcdc	235	}
663af342 PH	236
	237	EMITBUF(p, len);
	238	if (p == name) /* no ending quote needed */
	239	return 0;
	240
4f6fbcdc JH	241	if (!no_dq)
4f6fbcdc JH	242	EMIT('"');
663af342 PH	243	return count;
663af342 PH	244	}
4f6fbcdc	245
663af342 PH	246	size_t quote_c_style(const char name, struct strbuf sb, FILE *fp, int nodq)
	247	{
	248	return quote_c_style_counted(name, -1, sb, fp, nodq);
4f6fbcdc JH	249	}
4f6fbcdc JH	250
d5625091 JH	251	void quote_two_c_style(struct strbuf sb, const char prefix, const char *path, int nodq)
	252	{
	253	if (quote_c_style(prefix, NULL, NULL, 0) \|\|
	254	quote_c_style(path, NULL, NULL, 0)) {
	255	if (!nodq)
	256	strbuf_addch(sb, '"');
	257	quote_c_style(prefix, sb, NULL, 1);
	258	quote_c_style(path, sb, NULL, 1);
	259	if (!nodq)
	260	strbuf_addch(sb, '"');
	261	} else {
	262	strbuf_addstr(sb, prefix);
	263	strbuf_addstr(sb, path);
	264	}
	265	}
	266
663af342	267	void write_name_quoted(const char name, FILE fp, int terminator)
9ef2b3cb	268	{
663af342 PH	269	if (terminator) {
	270	quote_c_style(name, NULL, fp, 0);
	271	} else {
	272	fputs(name, fp);
	273	}
	274	fputc(terminator, fp);
	275	}
	276
2af202be LT	277	void write_name_quotedpfx(const char *pfx, size_t pfxlen,
2af202be LT	278	const char name, FILE fp, int terminator)
663af342 PH	279	{
	280	int needquote = 0;
	281
	282	if (terminator) {
	283	needquote = next_quote_pos(pfx, pfxlen) < pfxlen
	284	\|\| name[next_quote_pos(name, -1)];
	285	}
	286	if (needquote) {
	287	fputc('"', fp);
	288	quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
	289	quote_c_style(name, NULL, fp, 1);
	290	fputc('"', fp);
	291	} else {
	292	fwrite(pfx, pfxlen, 1, fp);
	293	fputs(name, fp);
	294	}
	295	fputc(terminator, fp);
9ef2b3cb JH	296	}
9ef2b3cb JH	297
b167cffb CB	298	static const char path_relative(const char in, int len,
	299	struct strbuf sb, const char prefix,
	300	int prefix_len);
	301
	302	void write_name_quoted_relative(const char *name, size_t len,
	303	const char *prefix, size_t prefix_len,
	304	FILE *fp, int terminator)
a734d0b1	305	{
b167cffb CB	306	struct strbuf sb = STRBUF_INIT;
	307
	308	name = path_relative(name, len, &sb, prefix, prefix_len);
	309	write_name_quoted(name, fp, terminator);
	310
	311	strbuf_release(&sb);
	312	}
	313
	314	/*
	315	* Give path as relative to prefix.
	316	*
	317	* The strbuf may or may not be used, so do not assume it contains the
	318	* returned path.
	319	*/
	320	static const char path_relative(const char in, int len,
	321	struct strbuf sb, const char prefix,
	322	int prefix_len)
	323	{
	324	int off, i;
a734d0b1 DP	325
	326	if (len < 0)
	327	len = strlen(in);
b167cffb CB	328	if (prefix && prefix_len < 0)
	329	prefix_len = strlen(prefix);
	330
	331	off = 0;
	332	i = 0;
	333	while (i < prefix_len && i < len && prefix[i] == in[i]) {
	334	if (prefix[i] == '/')
	335	off = i + 1;
	336	i++;
	337	}
	338	in += off;
	339	len -= off;
	340
	341	if (i >= prefix_len)
	342	return in;
a734d0b1	343
b167cffb CB	344	strbuf_reset(sb);
	345	strbuf_grow(sb, len);
	346
	347	while (i < prefix_len) {
	348	if (prefix[i] == '/')
	349	strbuf_addstr(sb, "../");
	350	i++;
a734d0b1	351	}
b167cffb CB	352	strbuf_add(sb, in, len);
	353
	354	return sb->buf;
	355	}
a734d0b1	356
b167cffb CB	357	/* quote path as relative to the given prefix */
	358	char quote_path_relative(const char in, int len,
	359	struct strbuf out, const char prefix)
	360	{
	361	struct strbuf sb = STRBUF_INIT;
	362	const char *rel = path_relative(in, len, &sb, prefix, -1);
	363	strbuf_reset(out);
	364	quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
	365	strbuf_release(&sb);
a734d0b1	366
a734d0b1 DP	367	if (!out->len)
	368	strbuf_addstr(out, "./");
	369
	370	return out->buf;
	371	}
	372
4f6fbcdc JH	373	/*
	374	* C-style name unquoting.
	375	*
7fb1011e PH	376	* Quoted should point at the opening double quote.
	377	* + Returns 0 if it was able to unquote the string properly, and appends the
	378	* result in the strbuf `sb'.
	379	* + Returns -1 in case of error, and doesn't touch the strbuf. Though note
	380	* that this function will allocate memory in the strbuf, so calling
	381	* strbuf_release is mandatory whichever result unquote_c_style returns.
	382	*
	383	* Updates endp pointer to point at one past the ending double quote if given.
4f6fbcdc	384	*/
7fb1011e	385	int unquote_c_style(struct strbuf sb, const char quoted, const char **endp)
4f6fbcdc	386	{
7fb1011e PH	387	size_t oldlen = sb->len, len;
7fb1011e PH	388	int ch, ac;
4f6fbcdc JH	389
4f6fbcdc JH	390	if (*quoted++ != '"')
7fb1011e PH	391	return -1;
	392
	393	for (;;) {
	394	len = strcspn(quoted, "\"\\");
	395	strbuf_add(sb, quoted, len);
	396	quoted += len;
4f6fbcdc	397
7fb1011e PH	398	switch (*quoted++) {
	399	case '"':
	400	if (endp)
c8744d6a	401	*endp = quoted;
7fb1011e PH	402	return 0;
	403	case '\\':
	404	break;
	405	default:
	406	goto error;
	407	}
	408
	409	switch ((ch = *quoted++)) {
	410	case 'a': ch = '\a'; break;
	411	case 'b': ch = '\b'; break;
	412	case 'f': ch = '\f'; break;
	413	case 'n': ch = '\n'; break;
	414	case 'r': ch = '\r'; break;
	415	case 't': ch = '\t'; break;
	416	case 'v': ch = '\v'; break;
	417
	418	case '\\': case '"':
	419	break; /* verbatim */
	420
	421	/* octal values with first digit over 4 overflow */
	422	case '0': case '1': case '2': case '3':
4f6fbcdc	423	ac = ((ch - '0') << 6);
7fb1011e PH	424	if ((ch = *quoted++) < '0' \|\| '7' < ch)
7fb1011e PH	425	goto error;
4f6fbcdc	426	ac \|= ((ch - '0') << 3);
7fb1011e PH	427	if ((ch = *quoted++) < '0' \|\| '7' < ch)
7fb1011e PH	428	goto error;
4f6fbcdc JH	429	ac \|= (ch - '0');
	430	ch = ac;
	431	break;
	432	default:
7fb1011e	433	goto error;
4f6fbcdc	434	}
7fb1011e	435	strbuf_addch(sb, ch);
4f6fbcdc JH	436	}
4f6fbcdc JH	437
7fb1011e PH	438	error:
	439	strbuf_setlen(sb, oldlen);
	440	return -1;
4f6fbcdc JH	441	}
4f6fbcdc JH	442
9f613ddd JH	443	/* quoting as a string literal for other languages */
	444
	445	void perl_quote_print(FILE stream, const char src)
	446	{
	447	const char sq = '\'';
	448	const char bq = '\\';
	449	char c;
	450
	451	fputc(sq, stream);
	452	while ((c = *src++)) {
	453	if (c == sq \|\| c == bq)
	454	fputc(bq, stream);
	455	fputc(c, stream);
	456	}
	457	fputc(sq, stream);
	458	}
	459
	460	void python_quote_print(FILE stream, const char src)
	461	{
	462	const char sq = '\'';
	463	const char bq = '\\';
	464	const char nl = '\n';
	465	char c;
	466
	467	fputc(sq, stream);
	468	while ((c = *src++)) {
	469	if (c == nl) {
	470	fputc(bq, stream);
	471	fputc('n', stream);
	472	continue;
	473	}
	474	if (c == sq \|\| c == bq)
	475	fputc(bq, stream);
	476	fputc(c, stream);
	477	}
	478	fputc(sq, stream);
	479	}
5558e55c SP	480
	481	void tcl_quote_print(FILE stream, const char src)
	482	{
	483	char c;
	484
	485	fputc('"', stream);
	486	while ((c = *src++)) {
	487	switch (c) {
	488	case '[': case ']':
	489	case '{': case '}':
	490	case '$': case '\\': case '"':
	491	fputc('\\', stream);
	492	default:
	493	fputc(c, stream);
	494	break;
	495	case '\f':
	496	fputs("\\f", stream);
	497	break;
	498	case '\r':
	499	fputs("\\r", stream);
	500	break;
	501	case '\n':
	502	fputs("\\n", stream);
	503	break;
	504	case '\t':
	505	fputs("\\t", stream);
	506	break;
	507	case '\v':
	508	fputs("\\v", stream);
	509	break;
	510	}
	511	}
	512	fputc('"', stream);
	513	}