Staging
v0.5.1
v0.5.1
https://github.com/python/cpython
Tip revision: 1da43e5e916949c8e849e656d9d05fa4b9d6836c authored by Benjamin Peterson on 26 June 2009, 13:21:52 UTC
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
Tip revision: 1da43e5
grammar.c
/* Grammar implementation */
#include "Python.h"
#include "pgenheaders.h"
#include <ctype.h>
#include "token.h"
#include "grammar.h"
extern int Py_DebugFlag;
grammar *
newgrammar(int start)
{
grammar *g;
g = (grammar *)PyObject_MALLOC(sizeof(grammar));
if (g == NULL)
Py_FatalError("no mem for new grammar");
g->g_ndfas = 0;
g->g_dfa = NULL;
g->g_start = start;
g->g_ll.ll_nlabels = 0;
g->g_ll.ll_label = NULL;
g->g_accel = 0;
return g;
}
dfa *
adddfa(grammar *g, int type, char *name)
{
dfa *d;
g->g_dfa = (dfa *)PyObject_REALLOC(g->g_dfa,
sizeof(dfa) * (g->g_ndfas + 1));
if (g->g_dfa == NULL)
Py_FatalError("no mem to resize dfa in adddfa");
d = &g->g_dfa[g->g_ndfas++];
d->d_type = type;
d->d_name = strdup(name);
d->d_nstates = 0;
d->d_state = NULL;
d->d_initial = -1;
d->d_first = NULL;
return d; /* Only use while fresh! */
}
int
addstate(dfa *d)
{
state *s;
d->d_state = (state *)PyObject_REALLOC(d->d_state,
sizeof(state) * (d->d_nstates + 1));
if (d->d_state == NULL)
Py_FatalError("no mem to resize state in addstate");
s = &d->d_state[d->d_nstates++];
s->s_narcs = 0;
s->s_arc = NULL;
s->s_lower = 0;
s->s_upper = 0;
s->s_accel = NULL;
s->s_accept = 0;
return s - d->d_state;
}
void
addarc(dfa *d, int from, int to, int lbl)
{
state *s;
arc *a;
assert(0 <= from && from < d->d_nstates);
assert(0 <= to && to < d->d_nstates);
s = &d->d_state[from];
s->s_arc = (arc *)PyObject_REALLOC(s->s_arc, sizeof(arc) * (s->s_narcs + 1));
if (s->s_arc == NULL)
Py_FatalError("no mem to resize arc list in addarc");
a = &s->s_arc[s->s_narcs++];
a->a_lbl = lbl;
a->a_arrow = to;
}
int
addlabel(labellist *ll, int type, char *str)
{
int i;
label *lb;
for (i = 0; i < ll->ll_nlabels; i++) {
if (ll->ll_label[i].lb_type == type &&
strcmp(ll->ll_label[i].lb_str, str) == 0)
return i;
}
ll->ll_label = (label *)PyObject_REALLOC(ll->ll_label,
sizeof(label) * (ll->ll_nlabels + 1));
if (ll->ll_label == NULL)
Py_FatalError("no mem to resize labellist in addlabel");
lb = &ll->ll_label[ll->ll_nlabels++];
lb->lb_type = type;
lb->lb_str = strdup(str);
if (Py_DebugFlag)
printf("Label @ %8p, %d: %s\n", ll, ll->ll_nlabels,
PyGrammar_LabelRepr(lb));
return lb - ll->ll_label;
}
/* Same, but rather dies than adds */
int
findlabel(labellist *ll, int type, char *str)
{
int i;
for (i = 0; i < ll->ll_nlabels; i++) {
if (ll->ll_label[i].lb_type == type /*&&
strcmp(ll->ll_label[i].lb_str, str) == 0*/)
return i;
}
fprintf(stderr, "Label %d/'%s' not found\n", type, str);
Py_FatalError("grammar.c:findlabel()");
return 0; /* Make gcc -Wall happy */
}
/* Forward */
static void translabel(grammar *, label *);
void
translatelabels(grammar *g)
{
int i;
#ifdef Py_DEBUG
printf("Translating labels ...\n");
#endif
/* Don't translate EMPTY */
for (i = EMPTY+1; i < g->g_ll.ll_nlabels; i++)
translabel(g, &g->g_ll.ll_label[i]);
}
static void
translabel(grammar *g, label *lb)
{
int i;
if (Py_DebugFlag)
printf("Translating label %s ...\n", PyGrammar_LabelRepr(lb));
if (lb->lb_type == NAME) {
for (i = 0; i < g->g_ndfas; i++) {
if (strcmp(lb->lb_str, g->g_dfa[i].d_name) == 0) {
if (Py_DebugFlag)
printf(
"Label %s is non-terminal %d.\n",
lb->lb_str,
g->g_dfa[i].d_type);
lb->lb_type = g->g_dfa[i].d_type;
free(lb->lb_str);
lb->lb_str = NULL;
return;
}
}
for (i = 0; i < (int)N_TOKENS; i++) {
if (strcmp(lb->lb_str, _PyParser_TokenNames[i]) == 0) {
if (Py_DebugFlag)
printf("Label %s is terminal %d.\n",
lb->lb_str, i);
lb->lb_type = i;
free(lb->lb_str);
lb->lb_str = NULL;
return;
}
}
printf("Can't translate NAME label '%s'\n", lb->lb_str);
return;
}
if (lb->lb_type == STRING) {
if (isalpha(Py_CHARMASK(lb->lb_str[1])) ||
lb->lb_str[1] == '_') {
char *p;
char *src;
char *dest;
size_t name_len;
if (Py_DebugFlag)
printf("Label %s is a keyword\n", lb->lb_str);
lb->lb_type = NAME;
src = lb->lb_str + 1;
p = strchr(src, '\'');
if (p)
name_len = p - src;
else
name_len = strlen(src);
dest = (char *)malloc(name_len + 1);
if (!dest) {
printf("Can't alloc dest '%s'\n", src);
return;
}
strncpy(dest, src, name_len);
dest[name_len] = '\0';
free(lb->lb_str);
lb->lb_str = dest;
}
else if (lb->lb_str[2] == lb->lb_str[0]) {
int type = (int) PyToken_OneChar(lb->lb_str[1]);
if (type != OP) {
lb->lb_type = type;
free(lb->lb_str);
lb->lb_str = NULL;
}
else
printf("Unknown OP label %s\n",
lb->lb_str);
}
else if (lb->lb_str[2] && lb->lb_str[3] == lb->lb_str[0]) {
int type = (int) PyToken_TwoChars(lb->lb_str[1],
lb->lb_str[2]);
if (type != OP) {
lb->lb_type = type;
free(lb->lb_str);
lb->lb_str = NULL;
}
else
printf("Unknown OP label %s\n",
lb->lb_str);
}
else if (lb->lb_str[2] && lb->lb_str[3] && lb->lb_str[4] == lb->lb_str[0]) {
int type = (int) PyToken_ThreeChars(lb->lb_str[1],
lb->lb_str[2],
lb->lb_str[3]);
if (type != OP) {
lb->lb_type = type;
free(lb->lb_str);
lb->lb_str = NULL;
}
else
printf("Unknown OP label %s\n",
lb->lb_str);
}
else
printf("Can't translate STRING label %s\n",
lb->lb_str);
}
else
printf("Can't translate label '%s'\n",
PyGrammar_LabelRepr(lb));
}