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/* Parser generator main program */
#include <stdio.h>
#include "PROTO.h"
#include "grammar.h"
#include "node.h"
#include "parsetok.h"
#include "pgen.h"
int debugging;
#ifdef THINK_C
char *
askfile()
{
char buf[256];
static char name[256];
printf("Input file name: ");
if (fgets(buf, sizeof buf, stdin) == NULL) {
printf("EOF\n");
exit(1);
}
if (sscanf(buf, " %s ", name) != 1) {
printf("No file\n");
exit(1);
}
return name;
}
#endif
grammar *
getgrammar(filename)
char *filename;
{
FILE *fp;
node *n;
grammar *g0, *g;
fp = fopen(filename, "r");
if (fp == NULL) {
perror(filename);
exit(1);
}
g0 = meta_grammar();
n = NULL;
parsefile(fp, g0, g0->g_start, (char *)NULL, (char *)NULL, &n);
fclose(fp);
if (n == NULL) {
fprintf(stderr, "Parsing error.\n");
exit(1);
}
g = pgen(n);
if (g == NULL) {
printf("Bad grammar.\n");
exit(1);
}
return g;
}
main(argc, argv)
int argc;
char **argv;
{
grammar *g;
node *n;
FILE *fp;
char *filename;
#ifdef THINK_C
filename = askfile();
#else
if (argc != 2) {
fprintf(stderr, "usage: %s grammar\n", argv[0]);
exit(2);
}
filename = argv[1];
#endif
g = getgrammar(filename);
fp = fopen("graminit.c", "w");
if (fp == NULL) {
perror("graminit.c");
exit(1);
}
printf("Writing graminit.c ...\n");
printgrammar(g, fp);
fclose(fp);
fp = fopen("graminit.h", "w");
if (fp == NULL) {
perror("graminit.h");
exit(1);
}
printf("Writing graminit.h ...\n");
printnonterminals(g, fp);
fclose(fp);
exit(0);
}
void
fatal(msg)
char *msg;
{
fprintf(stderr, "pgen: FATAL ERROR: %s\n", msg);
exit(1);
}
/* TO DO:
- improve user interface
- check for duplicate definitions of names (instead of fatal err)
*/
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