GIT 0.99.9e

[git.git] / quote.c

diff --git a/quote.c b/quote.c
index 92e07f0..e662a7d 100644 (file)
--- a/quote.c
+++ b/quote.c
@@ -2,43 +2,95 @@
 #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.
  *