AUSAM/source/S/file.c

/*
 *
 *	file -- guess the type of file
 *
 *	file now knows about:	pascal objects
 *				pascal programs
 *				spitbol programs	('E.' format only)
 *				packed files
 *				dec object files (absolute loader)
 *				shared data a.outs
 *				new ar format
 */ 

int in;
int i 0;
char buf[512];
int *wd
{
	&buf[0]
};
char *fort[]
{
	"function", "subroutine", "common", "dimension", "block",
	"integer", "real", "data", "double", 0
};
char *asc[]
{
	"sys", "mov", "tst", "clr", "jmp", 0
};
char *c[]
{
	"int", "char", "float", "double", "struct", "extern",
	"unsigned", "static", 0
};
char *as[]
{
	"globl", "byte", "even", "text", "data", "bss", "comm", 0
};
char *pas[]
{
	"program", "begin", "procedure", "type", "var", "const", "end",
	"writeln", "function", 0
};
int ibuf[260];
main(argc, argv)
char **argv;
{
	extern fout;

	fout = dup(1);

	while(argc > 1)
	{
		printf("%s:	", argv[1]);
		type(argv[1]);
		flush();
		argc--;
		argv++;
	}
}

type(file)
char *file;
{
	int j, nl;
	char ch;
	int mbuf[20];


	if(stat(file, mbuf) == -1)
	{
		printf("can't stat\n");
		return;
	}
	switch(mbuf[2]&060000)
	{

	case 020000:
		printf("character");
		goto spcl;

	case 040000:
		printf("directory\n");
		return;

	case 060000:
		printf("block");
	spcl:
		printf(" special (%d/%d)\n", (mbuf[6]>>8)&0377, mbuf[6]&0377);
		return;
	}

	ibuf[0] = open(file, 0);
	if(ibuf[0] == -1)
	{
		printf("can't open\n");
		return;
	}
	in = read(ibuf[0], buf, 512);
	switch(*wd)
	{

	case 0407:
		printf("executable\n");
		goto out;

	case 0410:
		printf("pure executable\n");
		goto out;

	case 0411:
		printf("separate executable\n");
		goto out;

	case 0412:
		printf("shared data\n");
		goto out;

	case 0177555:
		printf("archive (old format)\n");
		goto out;
	case 0177545:
		printf("archive\n");
		goto out;

	case 01:
		printf("absolute loader (dec)\n");
		goto out;

	case 0404:
		printf("pascal object\n");
		goto out;

	case 017437:
		printf("packed\n");
		goto out;

	case 027105:
		printf("spitbol program\n");
		goto out;

	}

	i = 0;
	if(ccom() == 0)
		goto notc;
	while(buf[i] == '#')
	{
		j = i;
		while(buf[i++] != '\n')
		{
			if(i-j > 255)
			{
				printf("data\n");
				goto out;
			}
			if(i >= in)
				goto notc;
		}
		if(ccom() == 0)
			goto notc;
	}
check:
	if(lookup(c) == 1)
	{
		while((ch = buf[i++]) != ';' && ch != '{')
			if(i >= in)
				goto notc;
		printf("c program");
		goto outa;
	}
	nl = 0;
	while(buf[i] != '(')
	{
		if(buf[i] <= 0)
		{
			printf("data\n");
			goto out;
		}
		if(buf[i] == ';')
		{
			i++;
			goto check;
		}
		if(buf[i++] == '\n')
			if(nl++ > 6)
				goto notc;
		if(i >= in)
			goto notc;
	}
	while(buf[i] != ')')
	{
		if(buf[i++] == '\n')
			if(nl++ > 6)
				goto notc;
		if(i >= in)
			goto notc;
	}
	while(buf[i] != '{')
	{
		if(buf[i++] == '\n')
			if(nl++ > 6)
				goto notc;
		if(i >= in)
			goto notc;
	}
	printf("c program");
	goto outa;
notc:
	i = 0;
	while(buf[i] == '{')
	{
		while(buf[i++] != '}')
			if(i >= in)
				goto notpas;
	}
	if(lookup(pas) == 1)
	{
		printf("pascal program");
		goto outa;
	}
notpas:
	i = 0;
	while(buf[i] == 'c' || buf[i] == '#')
	{
		while(buf[i++] != '\n')
			if(i >= in)
				goto notfort;
	}
	if(lookup(fort) == 1)
	{
		printf("fortran");
		goto outa;
	}
notfort:
	i = 0;
	if(ascom() == 0)
		goto notas;
	j = i-1;
	if(buf[i] == '.')
	{
		i++;
		if(lookup(as) == 1)
		{
			printf("assembler program");
			goto outa;
		}
		else if(buf[j] == '\n')
		{
			printf("roff, nroff, or eqn input");
			goto outa;
		}
	}
	while(lookup(asc) == 0)
	{
		if(ascom() == 0)
			goto notas;
		while(buf[i] != '\n' && buf[i++] != ':')
			if(i >= in)
				goto notas;
		while(buf[i] == '\n' || buf[i] == ' ' || buf[i] == '\t')
			if(i++ >= in)
				goto notas;
		j = i-1;
		if(buf[i] == '.')
		{
			i++;
			if(lookup(as) == 1)
			{
				printf("assembler program");
				goto outa;
			}
			else if(buf[j] == '\n')
			{
				printf("roff, nroff, or eqn input");
				goto outa;
			}
		}
	}
	printf("assembler program");
	goto outa;
notas:
	for(i = 0; i < in; i++)
		if(buf[i] <= 0)
		{
			printf("data\n");
			goto out;
		}
	if((mbuf[2]&00111) != 0)
		printf("commands");
	else
		printf("probably text");
outa:
	while(i < in)
		if(buf[i++] <= 0)
		{
			printf(" with garbage\n");
			goto out;
		}
	while((in = read(ibuf[0], buf, 512)) > 0)
		for(i = 0; i < in; i++)
			if(buf[i] <= 0)
			{
				printf(" with garbage\n");
				goto out;
			}
	printf("\n");
out:
	close(ibuf[0]);
}
lookup(tab)
char *tab[];
{
	char r;
	int k, j, l;

	while(buf[i] == ' ' || buf[i] == '\t' || buf[i] == '\n')
		i++;
	for(j = 0; tab[j] != 0; j++)
	{
		l = 0;
		for(k = i; ((r = tab[j][l++]) == buf[k] && r != '\0'); k++);
		if(r == '\0')
			if(buf[k] == ' ' || buf[k] == '\n' || buf[k] == '\t' || buf[k] == '{' || buf[k] == '/')
			{
				i = k;
				return(1);
			}
	}
	return(0);
}
ccom()
{
	char cc;

	while((cc = buf[i]) == ' ' || cc == '\t' || cc == '\n')
		if(i++ >= in)
			return(0);
	if(buf[i] == '/' && buf[i+1] == '*')
	{
		i =+ 2;
		while(buf[i] != '*' || buf[i+1] != '/')
		{
			if(buf[i] == '\\')
				i =+ 2;
			else
				i++;
			if(i >= in)
				return(0);
		}
		if((i =+ 2) >= in)
			return(0);
	}
	if(buf[i] == '\n')
		if(ccom() == 0)
			return(0);
	return(1);
}
ascom()
{
	while(buf[i] == '/')
	{
		i++;
		while(buf[i++] != '\n')
			if(i >= in)
				return(0);
		while(buf[i] == '\n')
			if(i++ >= in)
				return(0);
	}
	return(1);
}