diff options
| -rw-r--r-- | libbb/process_escape_sequence.c | 64 |
1 files changed, 43 insertions, 21 deletions
diff --git a/libbb/process_escape_sequence.c b/libbb/process_escape_sequence.c index 9b57ff99e..28b1e3697 100644 --- a/libbb/process_escape_sequence.c +++ b/libbb/process_escape_sequence.c @@ -22,48 +22,69 @@ * */ -#include <string.h> #include <stdio.h> #include <limits.h> #include <ctype.h> #include "libbb.h" -#define isodigit(c) ((c) >= '0' && (c) <= '7') -#define hextobin(c) ((c)>='a'&&(c)<='f' ? (c)-'a'+10 : (c)>='A'&&(c)<='F' ? (c)-'A'+10 : (c)-'0') -#define octtobin(c) ((c) - '0') +#define WANT_HEX_ESCAPES 1 + +/* Usual "this only works for ascii compatible encodings" disclaimer. */ +#undef _tolower +#define _tolower(X) ((X)|((char) 0x20)) + char bb_process_escape_sequence(const char **ptr) { - const char *p, *q; - unsigned int num_digits, r, n, hexescape; static const char charmap[] = { 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', 0, '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' }; - n = r = hexescape = num_digits = 0; + const char *p; + const char *q; + unsigned int num_digits; + unsigned int r; + unsigned int n; + unsigned int d; + unsigned int base; + + num_digits = n = 0; + base = 8; q = *ptr; +#ifdef WANT_HEX_ESCAPES if (*q == 'x') { - hexescape++; ++q; + base = 16; + ++num_digits; } +#endif do { - if (hexescape && isxdigit(*q)) { - r = n * 16 + hextobin(*q); - } else if (isodigit(*q)) { - r = n * 8 + octtobin(*q); - } else { - break; + d = (unsigned int)(*q - '0'); +#ifdef WANT_HEX_ESCAPES + if (d >= 10) { + d = ((unsigned int)(_tolower(*q) - 'a')) + 10; } - if (r <= UCHAR_MAX) { - n = r; - ++q; - if (++num_digits < 3) { - continue; +#endif + + if (d >= base) { +#ifdef WANT_HEX_ESCAPES + if ((base == 16) && (!--num_digits)) { +/* return '\\'; */ + --q; } +#endif + break; } - break; - } while (1); + + r = n * base + d; + if (r > UCHAR_MAX) { + break; + } + + n = r; + ++q; + } while (++num_digits < 3); if (num_digits == 0) { /* mnemonic escape sequence? */ p = charmap; @@ -77,6 +98,7 @@ char bb_process_escape_sequence(const char **ptr) } *ptr = q; + return (char) n; } |