added pgf-service.c in the robust parser'

This commit is contained in:
kr.angelov
2012-05-25 07:27:29 +00:00
parent 723421fba3
commit fdcd0de336

View File

@@ -0,0 +1,309 @@
#include <stdarg.h>
#include <gu/map.h>
#include <gu/dump.h>
#include <gu/log.h>
#include <gu/enum.h>
#include <gu/file.h>
#include <pgf/pgf.h>
#include <pgf/data.h>
#include <pgf/parser.h>
#include <pgf/lexer.h>
#include <pgf/literals.h>
#include <pgf/linearize.h>
#include <pgf/expr.h>
#define NO_FCGI_DEFINES
#include <fcgi_stdio.h>
#include <unistd.h>
#include <stdlib.h>
#define ISXDIGIT(c) ( \
(c >= 48 && c <= 57) || \
((c & ~0x20) >= 65 && (c & ~0x20) <= 70) \
)
void
url_escape(char *str)
{
char *pr = str, *pw = str;
size_t len = strlen(str);
for (;;) {
if ((pr - str) >= len)
break;
if (*pr == '%' &&
((pr - str)+2) < len &&
ISXDIGIT(*(pr+1)) &&
ISXDIGIT(*(pr+2)))
{
pr++;
char hexstr[3];
hexstr[0] = *pr++;
hexstr[1] = *pr++;
hexstr[2] = 0;
char *ptr;
int ch = strtoul(hexstr, &ptr, 16);
*pw++ = (char) (ch & 0x7f);
}
else if(*pr == '+') {
*pw++ = ' ';
}
else {
*pw++ = *pr++;
}
}
*pw++ = 0;
}
static int
generate_graphviz_expr(PgfExpr expr, int *pid,
GuWriter* wtr, GuExn* err, GuPool* pool)
{
int id;
GuVariantInfo ei = gu_variant_open(expr);
switch (ei.tag) {
case PGF_EXPR_FUN: {
PgfExprFun* fun = ei.data;
id = (*pid)++;
gu_printf(wtr, err, "n%d[label = \"", id);
gu_string_write(fun->fun, wtr, err);
gu_puts("\", style = \"solid\", shape = \"plaintext\"]\n", wtr, err);
break;
}
case PGF_EXPR_APP: {
PgfExprApp* app = ei.data;
id = generate_graphviz_expr(app->fun, pid, wtr, err, pool);
int arg_id = generate_graphviz_expr(app->arg, pid, wtr, err, pool);
gu_printf(wtr, err, "n%d -- n%d [style = \"solid\"]\n", id, arg_id);
break;
}
case PGF_EXPR_ABS:
case PGF_EXPR_LIT: {
PgfExprLit* lit = ei.data;
id = (*pid)++;
gu_printf(wtr, err, "n%d[label = \"", id);
GuVariantInfo ei = gu_variant_open(lit->lit);
switch (ei.tag) {
case PGF_LITERAL_STR: {
PgfLiteralStr* lit = ei.data;
gu_puts("\\\"", wtr, err);
gu_string_write(lit->val, wtr, err);
gu_puts("\\\"", wtr, err);
break;
}
case PGF_LITERAL_INT: {
PgfLiteralInt* lit = ei.data;
gu_printf(wtr, err, "%d", lit->val);
break;
}
case PGF_LITERAL_FLT: {
PgfLiteralFlt* lit = ei.data;
gu_printf(wtr, err, "%lf", lit->val);
break;
}
default:
gu_impossible();
}
gu_puts("\", style = \"solid\", shape = \"plaintext\"]\n", wtr, err);
break;
}
case PGF_EXPR_META:
id = (*pid)++;
gu_printf(wtr, err, "n%d[label = \"?\", style = \"solid\", shape = \"plaintext\"]\n", id);
break;
case PGF_EXPR_VAR:
case PGF_EXPR_TYPED:
case PGF_EXPR_IMPL_ARG:
gu_impossible();
break;
default:
gu_impossible();
}
return id;
}
static void
generate_graphviz(PgfExpr expr, GuWriter* wtr, GuExn* err, GuPool* pool)
{
int id = 0;
gu_puts("graph {\n", wtr, err);
generate_graphviz_expr(expr, &id, wtr, err, pool);
gu_puts("}", wtr, err);
}
static int
render(PgfExpr expr, GuPool* pool)
{
int pid;
int pc[2]; /* Parent to child pipe */
int cp[2]; /* Child to parent pipe */
char ch;
/* Make pipes */
if (pipe(pc) < 0)
return 0;
if (pipe(cp) < 0)
return 0;
/* Create a child to run command. */
switch (pid = fork())
{
case -1:
return 0;
case 0:
/* Child. */
dup2(cp[1], 1); /* Make stdout go to write
end of pipe. */
dup2(pc[0], 0); /* Make stdin come from read
end of pipe. */
close(pc[1]);
close(cp[0]);
char *args[] = {"dot", "-Tsvg", NULL};
execvp(args[0], args);
exit(1);
default: {
/* Parent. */
FILE* fstream = fdopen(pc[1], "w");
GuOut* out = gu_file_out(fstream, pool);
GuWriter* wtr = gu_new_utf8_writer(out, pool);
GuExn* err = gu_new_exn(NULL, gu_kind(type), pool);
generate_graphviz(expr, wtr, err, pool);
fclose(fstream);
close(cp[1]);
while (read(cp[0], &ch, 1) == 1)
{
FCGI_putchar(ch);
}
return 1;
}
}
}
int main ()
{
// Create the pool that is used to allocate everything
GuPool* pool = gu_new_pool();
int status = EXIT_SUCCESS;
FILE* infile = fopen("/home/krasimir/www.grammaticalframework.org/examples/PennTreebank/ParseEngAbs.pgf", "r");
if (infile == NULL) {
fprintf(stderr, "couldn't open the grammar\n");
status = EXIT_FAILURE;
goto fail;
}
// Create an input stream from the input file
GuIn* in = gu_file_in(infile, pool);
// Create an exception frame that catches all errors.
GuExn* err = gu_new_exn(NULL, gu_kind(type), pool);
// Read the PGF grammar.
PgfPGF* pgf = pgf_read(in, pool, err);
// If an error occured, it shows in the exception frame
if (!gu_ok(err)) {
fprintf(stderr, "Reading PGF failed\n");
status = EXIT_FAILURE;
goto fail_read;
}
GuString cat = gu_str_string("Utt", pool);
GuString lang = gu_str_string("ParseEng", pool);
PgfConcr* concr =
gu_map_get(pgf->concretes, &lang, PgfConcr*);
if (!concr) {
status = EXIT_FAILURE;
goto fail;
}
// Register a callback for the literal category Symbol
pgf_parser_add_literal(concr, gu_str_string("Symb", pool),
&pgf_nerc_literal_callback);
while (FCGI_Accept() >= 0) {
char* sentence = getenv("QUERY_STRING");
if (sentence == NULL ||
(sentence = strchr(sentence, '=')) == NULL) {
FCGI_printf("Content-type: text/html\r\n"
"\r\n"
"<body>Please specify a sentence to parse</body>\r\n");
} else {
sentence++;
// We create a temporary pool for translating a single
// sentence, so our memory usage doesn't increase over time.
GuPool* ppool = gu_new_pool();
char* tmp = gu_malloc(ppool, strlen(sentence)+2);
strcpy(tmp, sentence);
url_escape(tmp);
int len = strlen(tmp);
tmp[len] = '\n';
tmp[len+1] = '\0';
sentence = tmp;
// Begin parsing a sentence of the specified category
PgfParseState* state =
pgf_parser_init_state(concr, cat, 0, pool);
if (state == NULL) {
FCGI_printf("Content-type: text/html\r\n"
"\r\n"
"<body>Couldn't begin parsing</body>");
goto fail_request;
}
GuReader *rdr =
gu_string_reader(gu_str_string(sentence, ppool), ppool);
PgfLexer *lexer =
pgf_new_lexer(rdr, ppool);
// Tokenization
GuExn* lex_err = gu_new_exn(NULL, gu_kind(type), ppool);
PgfToken tok = pgf_lexer_next_token(lexer, lex_err, ppool);
while (!gu_exn_is_raised(lex_err)) {
// feed the token to get a new parse state
state = pgf_parser_next_state(state, tok, ppool);
if (!state) {
FCGI_printf("Content-type: text/html\r\n"
"\r\n"
"<body>Unexpected token</body>");
goto fail_request;
}
tok = pgf_lexer_next_token(lexer, lex_err, ppool);
}
// Now begin enumerating the resulting syntax trees
GuEnum* result = pgf_parse_result(state, ppool);
PgfExprProb* ep = gu_next(result, PgfExprProb*, ppool);
FCGI_printf("Content-type: image/svg+xml\r\n\r\n");
render(ep->expr, ppool);
fail_request:
gu_pool_free(ppool);
}
}
fail_read:
fclose(infile);
fail:
gu_pool_free(pool);
return status;
}