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/* MIX simulator, copyright 1994 by Darius Bacon */
#include "mix.h"
#include "asm.h"
#include "driver.h"
#include "parse.h"
#include "run.h"
#include "symbol.h"
#include <assert.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
static const char *current_file = NULL;
static unsigned line_number;
static unsigned num_errors = 0;
void fatal_error(const char *message, ...)
{
va_list args;
if (current_file) /*** of course, the error may not have anything to do with the file... */
fprintf(stderr, "FATAL ERROR (%s, line %u): ", current_file, line_number);
else
fprintf(stderr, "FATAL ERROR: ");
va_start(args, message);
vfprintf(stderr, message, args);
va_end(args);
fprintf(stderr, "\n");
exit(1);
}
static void (*error_handler)(const char *, va_list) = NULL;
void install_error_handler(void (*handler)(const char *, va_list))
{
error_handler = handler;
}
void error(const char *message, ...)
{
va_list args;
++num_errors;
va_start(args, message);
if (error_handler)
error_handler(message, args);
else
fatal_error("No error handler installed");
va_end(args);
}
void warn(const char *message, ...)
{
va_list args;
if (current_file)
fprintf(stderr, "WARNING (%s, line %u): ", current_file, line_number);
else
fprintf(stderr, "WARNING: ");
va_start(args, message);
vfprintf(stderr, message, args);
va_end(args);
fprintf(stderr, "\n");
}
/* --- Miscellany --- */
static FILE *open_file(const char *filename, const char *mode)
{
if (strcmp(filename, "-") == 0) {
assert(mode[0] == 'r' || mode[0] == 'w');
return mode[0] == 'w' ? stdout : stdin;
} else {
FILE *result = fopen(filename, mode);
if (!result)
fatal_error("%s: %s", filename, strerror(errno));
return result;
}
}
/* --- Main program --- */
static void assembler_error(const char *message, va_list args)
{
if (current_file)
fprintf(stderr, "ERROR (%s, line %u): ", current_file, line_number);
else
fprintf(stderr, "ERROR: ");
vfprintf(stderr, message, args);
fprintf(stderr, "\n");
}
static void assemble_file(const char *filename)
{
FILE *infile = open_file(filename, "r");
char line[257];
current_file = filename, line_number = 0;
while (fgets(line, sizeof line, infile)) {
++line_number;
assemble_line(line);
if (line[strlen(line) - 1] != '\n') {
if (!fgets(line, sizeof line, infile))
break; /* the file's last line had no '\n' */
else {
error("Line length exceeds 256 characters");
/* Skip the rest of the line */
while (line[strlen(line) - 1] != '\n')
if (!fgets(line, sizeof line, infile))
break;
}
}
}
if (ferror(infile))
error("%s: %s", filename, strerror(errno));
fclose(infile);
current_file = NULL;
}
int main(int argc, char **argv)
{
precompute_field_data();
/* Assemble the input: */
install_error_handler(assembler_error);
if (argc == 1)
assemble_file("-");
else {
int i;
for (i = 1; i < argc; ++i)
assemble_file(argv[i]);
}
resolve_generated_futures();
if (num_errors != 0) {
fprintf(stderr, "%u errors found\n", num_errors);
exit(1);
}
/* Now run it: */
set_initial_state();
{
clock_t finish, start = clock();
run();
finish = clock();
fprintf(stderr, "%g seconds elapsed\n",
(float)(finish - start) / CLOCKS_PER_SEC);
}
print_CPU_state();
return 0;
}
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