forth-cpu

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#include <stdio.h>
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#include <stdint.h>
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#include <stdbool.h>
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#define MAX_READ (3200)
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#define DEFAULT_ATTRIBUTES (0x3800u)
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static int printer(FILE *o, uint16_t n, bool binary_not_hex)
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{
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	n |= DEFAULT_ATTRIBUTES;
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	if(binary_not_hex) {
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		unsigned i;
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		for(i = 15; i <= 15; i--)
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			fputc(n & (1 << i) ? '1' : '0', o);
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		fputc('\n', o);
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	} else {
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		fprintf(o, "%04x\n", (unsigned)n);
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	}
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	return 0;
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}
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static void usage(const char *arg0)
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{
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	static const char *help = "\
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Generate initial VGA screen text for the H2 CPU project.\n\
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Options:\n\n\
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\t-h print this help message and exit\n\
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\t-g turn on generation mode - generate file full of spaces\n\n\
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This program turns a byte stream into a text file containing\n\
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a single 16-bit (doubling up the input data) ASCII file encoded\n\
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'1' and '0' characters.\n\n";
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	fprintf(stderr, "usage: %s -h -g\n", arg0);
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	fprintf(stderr, "%s", help);
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	fprintf(stderr, "%d characters are read in and converted.\n\n", MAX_READ);
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}
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int main(int argc, char **argv)
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{
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	size_t i;
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	int ia, gen = 0;
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	for(ia = 1; ia < argc && argv[ia][0] == '-'; ia++) {
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		switch(argv[ia][1]) {
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		case '\0': goto done; /* stop processing options */
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		case 'h':  usage(argv[0]);
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			   return -1;
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		case 'g':  gen = 1; break;
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		default:
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			   fprintf(stderr, "unknown option '%s'\n", argv[ia]);
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			   return -1;
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		}
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	}
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done:
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	if(argc != ia) {
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		fprintf(stderr, "too many arguments supplied\n");
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		return -1;
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	}
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	for(i = 0; i < MAX_READ; i++) {
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		int c = gen ? ' ' : fgetc(stdin);
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		if(c == EOF)
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			return 0;
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		if(printer(stdout, c, false) < 0)
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			return -1;
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	}
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	return 0;
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}
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