miller/c/parsing/mlr_dsl_wrapper.c
2017-04-08 00:35:36 -04:00

92 lines
2.9 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include "mlr_dsl_wrapper.h"
#include "mlr_dsl_lexer.h"
#include "mlr_dsl_parse.h"
#include "../lib/mlrutil.h"
#include "../dsl/mlr_dsl_ast.h"
#include "../containers/sllv.h"
// These prototypes are copied out manually from mlr_dsl_parse.c. With some
// more work I could have Lemon autogenerate these prototypes into
// mlr_dsl_parse.h.
void *mlr_dsl_lemon_parser_alloc(void *(*mallocProc)(size_t));
int mlr_dsl_lemon_parser_parse_token(
void *pvparser, /* The parser */
int yymajor, /* The major token code number */
mlr_dsl_ast_node_t* yyminor, /* The value for the token */
mlr_dsl_ast_t* past); /* Optional %extra_argument parameter */
void mlr_dsl_lemon_parser_free(
void *pvparser, /* The parser to be deleted */
void (*freeProc)(void*)); /* Function used to reclaim memory */
void mlr_dsl_ParseTrace(FILE *TraceFILE, char *zTracePrompt);
// ----------------------------------------------------------------
// http://flex.sourceforge.net/manual/Init-and-Destroy-Functions.html
// http://flex.sourceforge.net/manual/Extra-Data.html
// Returns linked list of mlr_dsl_ast_node_t*.
static mlr_dsl_ast_t* mlr_dsl_parse_inner(yyscan_t scanner, void* pvparser, mlr_dsl_ast_node_t** ppnode,
int trace_parse)
{
int lex_code;
int parse_code;
mlr_dsl_ast_t* past = mlr_dsl_ast_alloc();
if (trace_parse)
mlr_dsl_ParseTrace(stderr, "[DSLTRACE] ");
do {
lex_code = mlr_dsl_lexer_lex(scanner);
if (lex_code == -1) {
return NULL;
}
mlr_dsl_ast_node_t* plexed_node = *ppnode;
parse_code = mlr_dsl_lemon_parser_parse_token(pvparser, lex_code, plexed_node, past);
if (parse_code == 0) {
//mlr_dsl_ast_node_print(plexed_node);
return NULL;
}
} while (lex_code > 0);
if (-1 == lex_code) {
fprintf(stderr, "The scanner encountered an error.\n");
return NULL;
}
parse_code = mlr_dsl_lemon_parser_parse_token(pvparser, 0, NULL, past);
if (parse_code == 0)
return NULL;
return past;
}
// ----------------------------------------------------------------
// Returns linked list of mlr_dsl_ast_node_t*.
mlr_dsl_ast_t* mlr_dsl_parse(char* string, int trace_parse) {
mlr_dsl_ast_node_t* pnode = NULL;
yyscan_t scanner;
mlr_dsl_lexer_lex_init_extra(&pnode, &scanner);
void* pvparser = mlr_dsl_lemon_parser_alloc(malloc);
YY_BUFFER_STATE buf = NULL;
if (string == NULL) {
mlr_dsl_lexer_set_in(stdin, scanner);
} else {
YY_BUFFER_STATE buf = mlr_dsl_lexer__scan_string(string, scanner);
mlr_dsl_lexer__switch_to_buffer (buf, scanner);
}
mlr_dsl_ast_t* past = mlr_dsl_parse_inner(scanner, pvparser, &pnode, trace_parse);
if (buf != NULL)
mlr_dsl_lexer__delete_buffer(buf, scanner);
mlr_dsl_lexer_lex_destroy(scanner);
mlr_dsl_lemon_parser_free(pvparser, free);
return past;
}
// ----------------------------------------------------------------
void yytestcase(int ignored) {
}