Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

1 files changed, 523 insertions, 0 deletions

diff --git a/quote.c b/quote.c
new file mode 100644
index 000000000000..7f2aa6faa43f
--- /dev/null
+++ b/quote.c
@@ -0,0 +1,523 @@
+#include "cache.h"
+#include "quote.h"
+#include "argv-array.h"
+
+int quote_path_fully = 1;
+
+static inline int need_bs_quote(char c)
+{
+	return (c == '\'' || c == '!');
+}
+
+/* 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
+ * single quote pair.
+ *
+ * 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'
+ */
+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_buf_pretty(struct strbuf *dst, const char *src)
+{
+	static const char ok_punct[] = "+,-./:=@_^";
+	const char *p;
+
+	for (p = src; *p; p++) {
+		if (!isalpha(*p) && !isdigit(*p) && !strchr(ok_punct, *p)) {
+			sq_quote_buf(dst, src);
+			return;
+		}
+	}
+
+	/* if we get here, we did not need quoting */
+	strbuf_addstr(dst, src);
+}
+
+void sq_quotef(struct strbuf *dst, const char *fmt, ...)
+{
+	struct strbuf src = STRBUF_INIT;
+
+	va_list ap;
+	va_start(ap, fmt);
+	strbuf_vaddf(&src, fmt, ap);
+	va_end(ap);
+
+	sq_quote_buf(dst, src.buf);
+	strbuf_release(&src);
+}
+
+void sq_quote_argv(struct strbuf *dst, const char **argv)
+{
+	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]);
+	}
+}
+
+void sq_quote_argv_pretty(struct strbuf *dst, const char **argv)
+{
+	int i;
+
+	for (i = 0; argv[i]; i++) {
+		strbuf_addch(dst, ' ');
+		sq_quote_buf_pretty(dst, argv[i]);
+	}
+}
+
+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 '\\':
+			/*
+			 * Allow backslashed characters outside of
+			 * single-quotes only if they need escaping,
+			 * and only if we resume the single-quoted part
+			 * afterward.
+			 */
+			if (need_bs_quote(src[1]) && src[2] == '\'') {
+				*dst++ = src[1];
+				src += 2;
+				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);
+}
+
+static int sq_dequote_to_argv_internal(char *arg,
+				       const char ***argv, int *nr, int *alloc,
+				       struct argv_array *array)
+{
+	char *next = arg;
+
+	if (!*arg)
+		return 0;
+	do {
+		char *dequoted = sq_dequote_step(next, &next);
+		if (!dequoted)
+			return -1;
+		if (argv) {
+			ALLOC_GROW(*argv, *nr + 1, *alloc);
+			(*argv)[(*nr)++] = dequoted;
+		}
+		if (array)
+			argv_array_push(array, dequoted);
+	} while (next);
+
+	return 0;
+}
+
+int sq_dequote_to_argv(char *arg, const char ***argv, int *nr, int *alloc)
+{
+	return sq_dequote_to_argv_internal(arg, argv, nr, alloc, NULL);
+}
+
+int sq_dequote_to_argv_array(char *arg, struct argv_array *array)
+{
+	return sq_dequote_to_argv_internal(arg, NULL, NULL, NULL, array);
+}
+
+/* 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_quoted_relative(const char *name, const char *prefix,
+				FILE *fp, int terminator)
+{
+	struct strbuf sb = STRBUF_INIT;
+
+	name = relative_path(name, prefix, &sb);
+	write_name_quoted(name, fp, terminator);
+
+	strbuf_release(&sb);
+}
+
+/* quote path as relative to the given prefix */
+char *quote_path_relative(const char *in, const char *prefix,
+			  struct strbuf *out)
+{
+	struct strbuf sb = STRBUF_INIT;
+	const char *rel = relative_path(in, prefix, &sb);
+	strbuf_reset(out);
+	quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
+	strbuf_release(&sb);
+
+	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_buf(struct strbuf *sb, const char *src)
+{
+	const char sq = '\'';
+	const char bq = '\\';
+	char c;
+
+	strbuf_addch(sb, sq);
+	while ((c = *src++)) {
+		if (c == sq || c == bq)
+			strbuf_addch(sb, bq);
+		strbuf_addch(sb, c);
+	}
+	strbuf_addch(sb, sq);
+}
+
+void python_quote_buf(struct strbuf *sb, const char *src)
+{
+	const char sq = '\'';
+	const char bq = '\\';
+	const char nl = '\n';
+	char c;
+
+	strbuf_addch(sb, sq);
+	while ((c = *src++)) {
+		if (c == nl) {
+			strbuf_addch(sb, bq);
+			strbuf_addch(sb, 'n');
+			continue;
+		}
+		if (c == sq || c == bq)
+			strbuf_addch(sb, bq);
+		strbuf_addch(sb, c);
+	}
+	strbuf_addch(sb, sq);
+}
+
+void tcl_quote_buf(struct strbuf *sb, const char *src)
+{
+	char c;
+
+	strbuf_addch(sb, '"');
+	while ((c = *src++)) {
+		switch (c) {
+		case '[': case ']':
+		case '{': case '}':
+		case '$': case '\\': case '"':
+			strbuf_addch(sb, '\\');
+			/* fallthrough */
+		default:
+			strbuf_addch(sb, c);
+			break;
+		case '\f':
+			strbuf_addstr(sb, "\\f");
+			break;
+		case '\r':
+			strbuf_addstr(sb, "\\r");
+			break;
+		case '\n':
+			strbuf_addstr(sb, "\\n");
+			break;
+		case '\t':
+			strbuf_addstr(sb, "\\t");
+			break;
+		case '\v':
+			strbuf_addstr(sb, "\\v");
+			break;
+		}
+	}
+	strbuf_addch(sb, '"');
+}
+
+void basic_regex_quote_buf(struct strbuf *sb, const char *src)
+{
+	char c;
+
+	if (*src == '^') {
+		/* only beginning '^' is special and needs quoting */
+		strbuf_addch(sb, '\\');
+		strbuf_addch(sb, *src++);
+	}
+	if (*src == '*')
+		/* beginning '*' is not special, no quoting */
+		strbuf_addch(sb, *src++);
+
+	while ((c = *src++)) {
+		switch (c) {
+		case '[':
+		case '.':
+		case '\\':
+		case '*':
+			strbuf_addch(sb, '\\');
+			strbuf_addch(sb, c);
+			break;
+
+		case '$':
+			/* only the end '$' is special and needs quoting */
+			if (*src == '\0')
+				strbuf_addch(sb, '\\');
+			strbuf_addch(sb, c);
+			break;
+
+		default:
+			strbuf_addch(sb, c);
+			break;
+		}
+	}
+}