quote.c

   1 #include "cache.h"
   2 #include "quote.h"
   3
   4 /* Help to copy the thing properly quoted for the shell safety.
   5  * any single quote is replaced with '\'', any exclamation point
   6  * is replaced with '\!', and the whole thing is enclosed in a
   7  *
   8  * E.g.
   9  *  original     sq_quote     result
  10  *  name     ==> name      ==> 'name'
  11  *  a b      ==> a b       ==> 'a b'
  12  *  a'b      ==> a'\''b    ==> 'a'\''b'
  13  *  a!b      ==> a'\!'b    ==> 'a'\!'b'
  14  */
  15 #define EMIT(x) ( (++len < n) && (*bp++ = (x)) )
  16
  17 size_t sq_quote_buf(char *dst, size_t n, const char *src)
  18 {
  19         char c;
  20         char *bp = dst;
  21         size_t len = 0;
  22
  23         EMIT('\'');
  24         while ((c = *src++)) {
  25                 if (c == '\'' || c == '!') {
  26                         EMIT('\'');
  27                         EMIT('\\');
  28                         EMIT(c);
  29                         EMIT('\'');
  30                 } else {
  31                         EMIT(c);
  32                 }
  33         }
  34         EMIT('\'');
  35
  36         if ( n )
  37                 *bp = 0;
  38
  39         return len;
  40 }
  41
  42 char *sq_quote(const char *src)
  43 {
  44         char *buf;
  45         size_t cnt;
  46
  47         cnt = sq_quote_buf(NULL, 0, src) + 1;
  48         buf = xmalloc(cnt);
  49         sq_quote_buf(buf, cnt, src);
  50
  51         return buf;
  52 }
  53