fbt/sbase
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Add \e, \", \' and hex-escapes (\xH[H]) to unescape()

Browse Source 
So the users control the program, and the program doesn't
control the users.
This commit is contained in:
FRIGN 2015-02-14 22:54:18 +01:00
parent bf518929b9
commit d7a438b2f8
1 changed files with 24 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
libutil/unescape.c
View File

@ -17,13 +17,37 @@ unescape(char *s)
switch (s[i + 1]) {
case '\\': s[i] = '\\'; off++; break;
case '\'': s[i] = '\'', off++; break;
case '"': s[i] = '"', off++; break;
case 'a': s[i] = '\a'; off++; break;
case 'b': s[i] = '\b'; off++; break;
case 'e': s[i] = 033; off++; break;
case 'f': s[i] = '\f'; off++; break;
case 'n': s[i] = '\n'; off++; break;
case 'r': s[i] = '\r'; off++; break;
case 't': s[i] = '\t'; off++; break;
case 'v': s[i] = '\v'; off++; break;
case 'x':
/* "\xH[H]" hexadecimal escape */
for (m = i + 2; m < i + 1 + 3 && m < len; m++)
if ((s[m] < '0' && s[m] > '9') &&
(s[m] < 'A' && s[m] > 'F') &&
(s[m] < 'a' && s[m] > 'f'))
break;
if (m == i + 2)
eprintf("%s: invalid escape sequence '\\%c'\n", argv0, s[i + 1]);
off += m - i - 1;
for (--m, q = 0, factor = 1; m > i + 1; m--) {
if (s[m] >= '0' && s[m] <= '9')
q += (s[m] - '0') * factor;
else if (s[m] >= 'A' && s[m] <= 'F')
q += ((s[m] - 'A') + 10) * factor;
else if (s[m] >= 'a' && s[m] <= 'f')
q += ((s[m] - 'a') + 10) * factor;
factor *= 16;
}
s[i] = q;
break;
case '\0':
eprintf("%s: null escape sequence\n", argv0);
default: