X-Git-Url: https://git.octo.it/?p=git.git;a=blobdiff_plain;f=quote.c;h=06792d47c3e324ee9893a4e52035f0642f38005f;hp=5e6fda311c5f5fdaa20b7e9d64e46c13b7d9cce8;hb=HEAD;hpb=98e031f0bb6e857c684e6db24d03d22cfc1a532a

diff --git a/quote.c b/quote.c
index 5e6fda31..06792d47 100644
--- a/quote.c
+++ b/quote.c
@@ -2,40 +2,265 @@
 #include "quote.h"
 
 /* Help to copy the thing properly quoted for the shell safety.
- * any single quote is replaced with '\'', and the caller is
- * expected to enclose the result within a single quote pair.
+ * 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'
  */
-char *sq_quote(const char *src)
+#undef EMIT
+#define EMIT(x) ( (++len < n) && (*bp++ = (x)) )
+
+static inline int need_bs_quote(char c)
 {
-	static char *buf = NULL;
-	int cnt, c;
-	const char *cp;
-	char *bp;
+	return (c == '\'' || c == '!');
+}
 
-	/* count bytes needed to store the quoted string. */
-	for (cnt = 3, cp = src; *cp; cnt++, cp++)
-		if (*cp == '\'')
-			cnt += 3;
+size_t sq_quote_buf(char *dst, size_t n, const char *src)
+{
+	char c;
+	char *bp = dst;
+	size_t len = 0;
 
-	buf = xmalloc(cnt);
-	bp = buf;
-	*bp++ = '\'';
+	EMIT('\'');
 	while ((c = *src++)) {
-		if (c != '\'')
-			*bp++ = c;
-		else {
-			bp = strcpy(bp, "'\\''");
-			bp += 4;
+		if (need_bs_quote(c)) {
+			EMIT('\'');
+			EMIT('\\');
+			EMIT(c);
+			EMIT('\'');
+		} else {
+			EMIT(c);
 		}
 	}
-	*bp++ = '\'';
-	*bp = 0;
+	EMIT('\'');
+
+	if ( n )
+		*bp = 0;
+
+	return len;
+}
+
+char *sq_quote(const char *src)
+{
+	char *buf;
+	size_t cnt;
+
+	cnt = sq_quote_buf(NULL, 0, src) + 1;
+	buf = xmalloc(cnt);
+	sq_quote_buf(buf, cnt, src);
+
 	return buf;
 }
 
+char *sq_dequote(char *arg)
+{
+	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;
+			return arg;
+		case '\\':
+			c = *++src;
+			if (need_bs_quote(c) && *++src == '\'') {
+				*dst++ = c;
+				continue;
+			}
+		/* Fallthrough */
+		default:
+			return NULL;
+		}
+	}
+}
+
+/*
+ * C-style name quoting.
+ *
+ * Does one of three things:
+ *
+ * (1) if outbuf and outfp 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 outbuf is not NULL, it must point at a buffer large enough
+ *     to hold the c_style quoted version of name, enclosing double
+ *     quotes, and terminating NUL.  Fills outbuf with c_style quoted
+ *     version of name enclosed in double-quote pair.  Return value
+ *     is undefined.
+ *
+ * (3) if outfp is not NULL, outputs c_style quoted version of name,
+ *     but not enclosed in double-quote pair.  Return value is undefined.
+ */
+
+static int quote_c_style_counted(const char *name, int namelen,
+				 char *outbuf, FILE *outfp, int no_dq)
+{
+#undef EMIT
+#define EMIT(c) \
+	(outbuf ? (*outbuf++ = (c)) : outfp ? fputc(c, outfp) : (count++))
+
+#define EMITQ() EMIT('\\')
+
+	const char *sp;
+	int ch, count = 0, needquote = 0;
+
+	if (!no_dq)
+		EMIT('"');
+	for (sp = name; sp < name + namelen; sp++) {
+		ch = *sp;
+		if (!ch)
+			break;
+		if ((ch < ' ') || (ch == '"') || (ch == '\\') ||
+		    (ch == 0177)) {
+			needquote = 1;
+			switch (ch) {
+			case '\a': EMITQ(); ch = 'a'; break;
+			case '\b': EMITQ(); ch = 'b'; break;
+			case '\f': EMITQ(); ch = 'f'; break;
+			case '\n': EMITQ(); ch = 'n'; break;
+			case '\r': EMITQ(); ch = 'r'; break;
+			case '\t': EMITQ(); ch = 't'; break;
+			case '\v': EMITQ(); ch = 'v'; break;
+
+			case '\\': /* fallthru */
+			case '"': EMITQ(); break;
+			default:
+				/* octal */
+				EMITQ();
+				EMIT(((ch >> 6) & 03) + '0');
+				EMIT(((ch >> 3) & 07) + '0');
+				ch = (ch & 07) + '0';
+				break;
+			}
+		}
+		EMIT(ch);
+	}
+	if (!no_dq)
+		EMIT('"');
+	if (outbuf)
+		*outbuf = 0;
+
+	return needquote ? count : 0;
+}
+
+int quote_c_style(const char *name, char *outbuf, FILE *outfp, int no_dq)
+{
+	int cnt = strlen(name);
+	return quote_c_style_counted(name, cnt, outbuf, outfp, no_dq);
+}
+
+/*
+ * C-style name unquoting.
+ *
+ * Quoted should point at the opening double quote.  Returns
+ * an allocated memory that holds unquoted name, which the caller
+ * should free when done.  Updates endp pointer to point at
+ * one past the ending double quote if given.
+ */
+
+char *unquote_c_style(const char *quoted, const char **endp)
+{
+	const char *sp;
+	char *name = NULL, *outp = NULL;
+	int count = 0, ch, ac;
+
+#undef EMIT
+#define EMIT(c) (outp ? (*outp++ = (c)) : (count++))
+
+	if (*quoted++ != '"')
+		return NULL;
+
+	while (1) {
+		/* first pass counts and allocates, second pass fills */
+		for (sp = quoted; (ch = *sp++) != '"'; ) {
+			if (ch == '\\') {
+				switch (ch = *sp++) {
+				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 */
+
+				case '0'...'7':
+					/* octal */
+					ac = ((ch - '0') << 6);
+					if ((ch = *sp++) < '0' || '7' < ch)
+						return NULL;
+					ac |= ((ch - '0') << 3);
+					if ((ch = *sp++) < '0' || '7' < ch)
+						return NULL;
+					ac |= (ch - '0');
+					ch = ac;
+					break;
+				default:
+					return NULL; /* malformed */
+				}
+			}
+			EMIT(ch);
+		}
+
+		if (name) {
+			*outp = 0;
+			if (endp)
+				*endp = sp;
+			return name;
+		}
+		outp = name = xmalloc(count + 1);
+	}
+}
+
+void write_name_quoted(const char *prefix, int prefix_len,
+		       const char *name, int quote, FILE *out)
+{
+	int needquote;
+
+	if (!quote) {
+	no_quote:
+		if (prefix_len)
+			fprintf(out, "%.*s", prefix_len, prefix);
+		fputs(name, out);
+		return;
+	}
+
+	needquote = 0;
+	if (prefix_len)
+		needquote = quote_c_style_counted(prefix, prefix_len,
+						  NULL, NULL, 0);
+	if (!needquote)
+		needquote = quote_c_style(name, NULL, NULL, 0);
+	if (needquote) {
+		fputc('"', out);
+		if (prefix_len)
+			quote_c_style_counted(prefix, prefix_len,
+					      NULL, out, 1);
+		quote_c_style(name, NULL, out, 1);
+		fputc('"', out);
+	}
+	else
+		goto no_quote;
+}