tr: fix overflow in expand and complement, fix stop after [:class:],

fix order of [:xdigit:], make tr require one param at least.

function                                             old     new   delta
expand                                              1743    1849    +106
tr_main                                              463     518     +55
complement                                            72      75      +3
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 3/0 up/down: 164/0)             Total: 164 bytes
This commit is contained in:
Denis Vlasenko 2009-03-02 12:05:57 +00:00
parent 1bfcc8b08e
commit 491d6e3b56

View File

@ -16,24 +16,31 @@
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* http://www.opengroup.org/onlinepubs/009695399/utilities/tr.html
* TODO: xdigit, graph, print
* TODO: graph, print
*/
#include "libbb.h"
#define ASCII 0377
enum {
ASCII = 256,
/* string buffer needs to be at least as big as the whole "alphabet".
* BUFSIZ == ASCII is ok, but we will realloc in expand
* even for smallest patterns, let's avoid that by using *2:
*/
TR_BUFSIZ = (BUFSIZ > ASCII*2) ? BUFSIZ : ASCII*2,
};
static void map(char *pvector,
unsigned char *string1, unsigned string1_len,
unsigned char *string2, unsigned string2_len)
char *string1, unsigned string1_len,
char *string2, unsigned string2_len)
{
char last = '0';
unsigned i, j;
for (j = 0, i = 0; i < string1_len; i++) {
if (string2_len <= j)
pvector[string1[i]] = last;
pvector[(unsigned char)(string1[i])] = last;
else
pvector[string1[i]] = last = string2[j++];
pvector[(unsigned char)(string1[i])] = last = string2[j++];
}
}
@ -43,139 +50,155 @@ static void map(char *pvector,
* Character classes, e.g. [:upper:] ==> A...Z
* Equiv classess, e.g. [=A=] ==> A (hmmmmmmm?)
*/
static unsigned expand(const char *arg, char *buffer)
static unsigned expand(const char *arg, char **buffer_p)
{
char *buffer_start = buffer;
char *buffer = *buffer_p;
unsigned pos = 0;
unsigned size = TR_BUFSIZ;
unsigned i; /* can't be unsigned char: must be able to hold 256 */
unsigned char ac;
while (*arg) {
if (pos + ASCII > size) {
size += ASCII;
*buffer_p = buffer = xrealloc(buffer, size);
}
if (*arg == '\\') {
arg++;
*buffer++ = bb_process_escape_sequence(&arg);
buffer[pos++] = bb_process_escape_sequence(&arg);
continue;
}
if (arg[1] == '-') { /* "0-9..." */
ac = arg[2];
if (ac == '\0') { /* "0-": copy verbatim */
*buffer++ = *arg++; /* copy '0' */
buffer[pos++] = *arg++; /* copy '0' */
continue; /* next iter will copy '-' and stop */
}
i = *arg;
i = (unsigned char) *arg;
while (i <= ac) /* ok: i is unsigned _int_ */
*buffer++ = i++;
buffer[pos++] = i++;
arg += 3; /* skip 0-9 */
continue;
}
if (*arg == '[') { /* "[xyz..." */
if ((ENABLE_FEATURE_TR_CLASSES || ENABLE_FEATURE_TR_EQUIV)
&& *arg == '['
) {
arg++;
i = *arg++;
/* "[xyz...", i=x, arg points to y */
if (ENABLE_FEATURE_TR_CLASSES && i == ':') {
i = (unsigned char) *arg++;
/* "[xyz...". i=x, arg points to y */
if (ENABLE_FEATURE_TR_CLASSES && i == ':') { /* [:class:] */
#define CLO ":]\0"
static const char classes[] ALIGN1 =
"alpha"CLO "alnum"CLO "digit"CLO
"lower"CLO "upper"CLO "space"CLO
"blank"CLO "punct"CLO "cntrl"CLO
"xdigit"CLO;
#define CLASS_invalid 0 /* we increment the retval */
#define CLASS_alpha 1
#define CLASS_alnum 2
#define CLASS_digit 3
#define CLASS_lower 4
#define CLASS_upper 5
#define CLASS_space 6
#define CLASS_blank 7
#define CLASS_punct 8
#define CLASS_cntrl 9
#define CLASS_xdigit 10
//#define CLASS_graph 11
//#define CLASS_print 12
enum {
CLASS_invalid = 0, /* we increment the retval */
CLASS_alpha = 1,
CLASS_alnum = 2,
CLASS_digit = 3,
CLASS_lower = 4,
CLASS_upper = 5,
CLASS_space = 6,
CLASS_blank = 7,
CLASS_punct = 8,
CLASS_cntrl = 9,
CLASS_xdigit = 10,
//CLASS_graph = 11,
//CLASS_print = 12,
};
smalluint j;
{
char *tmp;
/* xdigit needs 8, not 7 */
char *tmp = xstrndup(arg, 7 + (arg[0]=='x'));
i = 7 + (arg[0] == 'x');
tmp = xstrndup(arg, i);
j = index_in_strings(classes, tmp) + 1;
free(tmp);
}
if (j == CLASS_invalid)
goto skip_bracket;
arg += i;
if (j == CLASS_alnum || j == CLASS_digit || j == CLASS_xdigit) {
for (i = '0'; i <= '9'; i++)
*buffer++ = i;
buffer[pos++] = i;
}
if (j == CLASS_alpha || j == CLASS_alnum || j == CLASS_upper) {
for (i = 'A'; i <= 'Z'; i++)
*buffer++ = i;
buffer[pos++] = i;
}
if (j == CLASS_alpha || j == CLASS_alnum || j == CLASS_lower) {
for (i = 'a'; i <= 'z'; i++)
*buffer++ = i;
buffer[pos++] = i;
}
if (j == CLASS_space || j == CLASS_blank) {
*buffer++ = '\t';
buffer[pos++] = '\t';
if (j == CLASS_space) {
*buffer++ = '\n';
*buffer++ = '\v';
*buffer++ = '\f';
*buffer++ = '\r';
buffer[pos++] = '\n';
buffer[pos++] = '\v';
buffer[pos++] = '\f';
buffer[pos++] = '\r';
}
*buffer++ = ' ';
buffer[pos++] = ' ';
}
if (j == CLASS_punct || j == CLASS_cntrl) {
for (i = '\0'; i <= ASCII; i++)
for (i = '\0'; i < ASCII; i++) {
if ((j == CLASS_punct && isprint(i) && !isalnum(i) && !isspace(i))
|| (j == CLASS_cntrl && iscntrl(i)))
*buffer++ = i;
|| (j == CLASS_cntrl && iscntrl(i))
) {
buffer[pos++] = i;
}
}
}
if (j == CLASS_xdigit) {
for (i = 'A'; i <= 'F'; i++) {
*buffer++ = i;
*buffer++ = i | 0x20;
buffer[pos + 6] = i | 0x20;
buffer[pos++] = i;
}
pos += 6;
}
if (j == CLASS_invalid) {
*buffer++ = '[';
*buffer++ = ':';
continue;
}
break;
}
/* "[xyz...", i=x, arg points to y */
if (ENABLE_FEATURE_TR_EQUIV && i == '=') { /* [=CHAR=] */
*buffer++ = *arg; /* copy CHAR */
if (!*arg || arg[1] != '=' || arg[2] != ']')
buffer[pos++] = *arg; /* copy CHAR */
if (!arg[0] || arg[1] != '=' || arg[2] != ']')
bb_show_usage();
arg += 3; /* skip CHAR=] */
continue;
}
/* The rest of [xyz... cases is treated as normal
* string, '[' has no special meaning here:
/* The rest of "[xyz..." cases is treated as normal
* string, "[" has no special meaning here:
* tr "[a-z]" "[A-Z]" can be written as tr "a-z" "A-Z",
* also try tr "[a-z]" "_A-Z+" and you'll see that
* [] is not special here.
*/
*buffer++ = '[';
arg--; /* points to x */
continue;
skip_bracket:
arg -= 2; /* points to "[" in "[xyz..." */
}
*buffer++ = *arg++;
buffer[pos++] = *arg++;
}
return (buffer - buffer_start);
return pos;
}
/* NB: buffer is guaranteed to be at least TR_BUFSIZE
* (which is >= ASCII) big.
*/
static int complement(char *buffer, int buffer_len)
{
int ch, j, len;
char conv[ASCII + 2];
int len;
char conv[ASCII];
unsigned char ch;
len = 0;
for (ch = '\0'; ch <= ASCII; ch++) {
for (j = 0; j < buffer_len; j++)
if (buffer[j] == ch)
goto next_ch;
/* Didn't find it */
conv[len++] = (char) ch;
next_ch:
continue;
ch = '\0';
while (1) {
if (memchr(buffer, ch, buffer_len) == NULL)
conv[len++] = ch;
if (++ch == '\0')
break;
}
memcpy(buffer, conv, len);
return len;
@ -190,54 +213,56 @@ int tr_main(int argc UNUSED_PARAM, char **argv)
size_t in_index, out_index;
unsigned last = UCHAR_MAX + 1; /* not equal to any char */
unsigned char coded, c;
unsigned char *output = xmalloc(BUFSIZ);
char *vector = xzalloc((ASCII+1) * 3);
char *invec = vector + (ASCII+1);
char *outvec = vector + (ASCII+1) * 2;
char *str1 = xmalloc(TR_BUFSIZ);
char *str2 = xmalloc(TR_BUFSIZ);
int str2_length;
int str1_length;
char *vector = xzalloc(ASCII * 3);
char *invec = vector + ASCII;
char *outvec = vector + ASCII * 2;
#define TR_OPT_complement (1 << 0)
#define TR_OPT_delete (1 << 1)
#define TR_OPT_squeeze_reps (1 << 2)
flags = getopt32(argv, "+cds"); /* '+': stop at first non-option */
argv += optind;
for (i = 0; i <= ASCII; i++) {
for (i = 0; i < ASCII; i++) {
vector[i] = i;
/*invec[i] = outvec[i] = FALSE; - done by xzalloc */
}
#define tr_buf bb_common_bufsiz1
if (*argv != NULL) {
int output_length = 0;
int input_length;
opt_complementary = "-1";
flags = getopt32(argv, "+cds"); /* '+': stop at first non-option */
argv += optind;
input_length = expand(*argv++, tr_buf);
str1_length = expand(*argv++, &str1);
str2_length = 0;
if (flags & TR_OPT_complement)
input_length = complement(tr_buf, input_length);
str1_length = complement(str1, str1_length);
if (*argv) {
if (argv[0][0] == '\0')
bb_error_msg_and_die("STRING2 cannot be empty");
output_length = expand(*argv, (char *)output);
map(vector, (unsigned char *)tr_buf, input_length, output, output_length);
}
for (i = 0; i < input_length; i++)
invec[(unsigned char)tr_buf[i]] = TRUE;
for (i = 0; i < output_length; i++)
outvec[output[i]] = TRUE;
str2_length = expand(*argv, &str2);
map(vector, str1, str1_length,
str2, str2_length);
}
for (i = 0; i < str1_length; i++)
invec[(unsigned char)(str1[i])] = TRUE;
for (i = 0; i < str2_length; i++)
outvec[(unsigned char)(str2[i])] = TRUE;
goto start_from;
/* In this loop, str1 space is reused as input buffer,
* str2 - as output one. */
for (;;) {
/* If we're out of input, flush output and read more input. */
if ((ssize_t)in_index == read_chars) {
if (out_index) {
xwrite(STDOUT_FILENO, (char *)output, out_index);
xwrite(STDOUT_FILENO, str2, out_index);
start_from:
out_index = 0;
}
read_chars = safe_read(STDIN_FILENO, tr_buf, BUFSIZ);
read_chars = safe_read(STDIN_FILENO, str1, TR_BUFSIZ);
if (read_chars <= 0) {
if (read_chars < 0)
bb_perror_msg_and_die(bb_msg_read_error);
@ -245,14 +270,16 @@ int tr_main(int argc UNUSED_PARAM, char **argv)
}
in_index = 0;
}
c = tr_buf[in_index++];
c = str1[in_index++];
if ((flags & TR_OPT_delete) && invec[c])
continue;
coded = vector[c];
if ((flags & TR_OPT_squeeze_reps) && last == coded
&& (invec[c] || outvec[coded]))
&& (invec[c] || outvec[coded])
) {
continue;
output[out_index++] = last = coded;
}
str2[out_index++] = last = coded;
}
return EXIT_SUCCESS;