X-Git-Url: https://git.octo.it/?p=git.git;a=blobdiff_plain;f=quote.c;h=06792d47c3e324ee9893a4e52035f0642f38005f;hp=9d5d0bcb0f0e32b95e27d32efe6d725479d28f76;hb=HEAD;hpb=29504118f8528f658fd0bfc02d8d78d4c01dc2cc

diff --git a/quote.c b/quote.c
index 9d5d0bcb..06792d47 100644
--- a/quote.c
+++ b/quote.c
@@ -12,8 +12,14 @@
  *  a'b      ==> a'\''b    ==> 'a'\''b'
  *  a!b      ==> a'\!'b    ==> 'a'\!'b'
  */
+#undef EMIT
 #define EMIT(x) ( (++len < n) && (*bp++ = (x)) )
 
+static inline int need_bs_quote(char c)
+{
+	return (c == '\'' || c == '!');
+}
+
 size_t sq_quote_buf(char *dst, size_t n, const char *src)
 {
 	char c;
@@ -22,7 +28,7 @@ size_t sq_quote_buf(char *dst, size_t n, const char *src)
 
 	EMIT('\'');
 	while ((c = *src++)) {
-		if (c == '\'' || c == '!') {
+		if (need_bs_quote(c)) {
 			EMIT('\'');
 			EMIT('\\');
 			EMIT(c);
@@ -51,3 +57,210 @@ char *sq_quote(const char *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;
+}