static int re_do_compile_fastmap(unsigned char *buffer, int used, int pos,
unsigned char *can_be_null,
unsigned char *fastmap)
{
unsigned char small_visited[512], *visited;
if (used <= sizeof(small_visited))
visited = small_visited;
else
{
visited = malloc(used);
if (!visited)
return 0;
}
*can_be_null = 0;
memset(fastmap, 0, 256);
memset(visited, 0, used);
re_compile_fastmap_aux(buffer, pos, visited, can_be_null, fastmap);
if (visited != small_visited)
free(visited);
return 1;
}
static void re_compile_fastmap_aux(unsigned char *code, int pos,
unsigned char *visited,
unsigned char *can_be_null,
unsigned char *fastmap)
{
int a;
int b;
int syntaxcode;
if (visited[pos])
return; /* we have already been here */
visited[pos] = 1;
for (;;)
switch (code[pos++]) {
case Cend:
{
*can_be_null = 1;
return;
}
case Cbol:
case Cbegbuf:
case Cendbuf:
case Cwordbeg:
case Cwordend:
case Cwordbound:
case Cnotwordbound:
{
for (a = 0; a < 256; a++)
fastmap[a] = 1;
break;
}
case Csyntaxspec:
{
syntaxcode = code[pos++];
for (a = 0; a < 256; a++)
if (SYNTAX(a) & syntaxcode)
fastmap[a] = 1;
return;
}
case Cnotsyntaxspec:
{
syntaxcode = code[pos++];
for (a = 0; a < 256; a++)
if (!(SYNTAX(a) & syntaxcode) )
fastmap[a] = 1;
return;
}
case Ceol:
{
fastmap['\n'] = 1;
if (*can_be_null == 0)
*can_be_null = 2; /* can match null, but only at end of buffer*/
return;
}
case Cset:
{
for (a = 0; a < 256/8; a++)
if (code[pos + a] != 0)
for (b = 0; b < 8; b++)
if (code[pos + a] & (1 << b))
fastmap[(a << 3) + b] = 1;
pos += 256/8;
return;
}
case Cexact:
{
fastmap[(unsigned char)code[pos]] = 1;
return;
}
case Canychar:
{
for (a = 0; a < 256; a++)
if (a != '\n')
fastmap[a] = 1;
return;
}
case Cstart_memory:
case Cend_memory:
{
pos++;
break;
}
case Cmatch_memory:
{
for (a = 0; a < 256; a++)
fastmap[a] = 1;
*can_be_null = 1;
return;
}
case Cjump:
case Cdummy_failure_jump:
case Cupdate_failure_jump:
case Cstar_jump:
{
a = (unsigned char)code[pos++];
a |= (unsigned char)code[pos++] << 8;
pos += (int)SHORT(a);
if (visited[pos])
{
/* argh... the regexp contains empty loops. This is not
good, as this may cause a failure stack overflow when
matching. Oh well. */
/* this path leads nowhere; pursue other paths. */
return;
}
visited[pos] = 1;
break;
}
case Cfailure_jump:
{
a = (unsigned char)code[pos++];
a |= (unsigned char)code[pos++] << 8;
a = pos + (int)SHORT(a);
re_compile_fastmap_aux(code, a, visited, can_be_null, fastmap);
break;
}
case Crepeat1:
{
pos += 2;
break;
}
default:
{
PyErr_SetString(PyExc_SystemError, "Unknown regex opcode: memory corrupted?");
return;
/*NOTREACHED*/
}
}
}
