filetype.c

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C语言 代码 · 共 943 行 · 第 1/2 页

#ifndef lint
static char *sccsid = "@(#)filetype.c	4.1    (ULTRIX)        7/17/90";
#endif	lint

/****************************************************************
 *								*
 *			Copyright (c) 1985 by			*
 *		Digital Equipment Corporation, Maynard, MA	*
 *			All rights reserved.			*
 *								*
 *   This software is furnished under a license and may be used *
 *   and copied  only  in accordance with the terms of such	*
 *   license and with the  inclusion  of  the  above  copyright *
 *   notice. This software  or  any  other copies thereof may	*
 *   not be provided or otherwise made available to any other	*
 *   person.  No title to and ownership of the software is	*
 *   hereby transferred.					*
 *								*
 *   The information in this software is subject to change	*
 *   without  notice  and should not be construed as a		*
 *   commitment by Digital  Equipment Corporation.		*
 *								*
 *   Digital assumes  no responsibility   for  the use  or	*
 *   reliability of its software on equipment which is not	*
 *   supplied by Digital.					*
 *								*
 ****************************************************************/
/**/
/*
 *
 *	File name:
 *
 *	    filetype.c
 *
 *	Source file description:
 *
 *		This file contains logic to determine the
 *		general type of file specified by the caller.
 *		ie. Is it binary, text, library, etc..
 *
 *		(further documentation below)
 *
 *		It is used by the Labeled Tape Facility (LTF)
 *		in order to determine the type that the Unix
 *		file should take on whence it becomes an
 *		ANSI tape file.
 *
 *
 *	Functions:
 *
 *	ascom()		...
 *	ccom()		...
 *	english()	...
 *	Filetype()	Top level logic to determine file type.
 *	lookupe()	...
 *	troffint()	Check for  troff intermediate file
 *
 *
 *	Compile:
 *
 *	    cc -O -c filetype.c		 <- For Ultrix-32/32m
 *
 *	    cc CFLAGS=-DU11-O filetype.c <- For Ultrix-11
 *
 *
 *	Modification history:
 *	~~~~~~~~~~~~~~~~~~~~
 *
 *	revision			comments
 *	--------	-----------------------------------------------
 *	  01.1		23-August-89	Sam Lambert
 *			Modified Filetype() to handle non-null terminated
 *			"ascii" files (U32_SPR #00095).
 *
 *	  01.0		09-April-85	Ray Glaser
 *			Create orginal version.
 *	
 */
/**/
/*
 * ->	Local includes
 */

#include "ltfdefs.h"	/* Common LTF definitions */

/*
 * ->	Local defines  "required for / defined by"  this module
 */

#define	MBUFSIZ	1024	/* Chunk of file to read for "typing" */
#define NL	012	/* Newline character */
#define	NLM	123	/* Used to check for 'c' code */

/*
 * ->	Globals for this module only
 */

char	*as[] = {
	"globl","byte","align","text","data","comm",0};

char	*asc[] = {
	"chmk","mov","tst","clr","jmp",0};

char	buf[MBUFSIZ];

char	*c[] = {
	"int","char","float","double","struct","extern",0};

char	*com[] = { "alias",
	"date","cc","xref","pr","pr50","CFLAGS","lpr","rm","FILES",
	"tar","mdtar","sync","make","/etc","/bin","for","case",
	"echo","do","umask","set","stty","setenv",
	00 };

int	errno;
char	*fort[] = {
	"function","subroutine","common","dimension","block","integer",
	"real","data","double",0};

int	i  = 0;
FILE	*ifile;
int	in;
char	*troff[] = {	/* new troff intermediate lang */
	"x","T","res","init","font","202","V0","p1",0};

int	Type;	/* Tentative file type value */
/**/
/*
 *
 * Function:
 *
 *	Filetype
 *
 * Function Description:
 *
 *	This function attempts to determine the type of Unix disk file.
 *	It returns a generalized file type indication as defined in
 *	the include file "filetypes.h".
 *
 * Arguments:
 *
 *
 *	char	*file		Points to a null terminated string
 *				assumed to be the desired file name
 *				to be typed.
 *
 *	char	*caller		Points to a string defining the desired
 *				routine name for messages to stderr.
 *
 * Return value(s):
 *
 *	int	value
 *
 *	Zero if the file type could not be determined, else:
 *	one of the file types defined in "filetypes.h".
 *	Additionally, the character string variables "Tftypes"
 *	is filled with a 3 character representation of the
 *	true Ultrix disk file type. (see README.1 file).
 *	
 * 
 * Side Effects:
 *
 *	This function outputs error messages to stderr if any problems
 *	occur during the attempt to access/type the given file.
 *
 */

/**/
/*
 *	FILETYPE	Determination thereof..
 */

Filetype(file,caller)

	char	*caller;
	char	*file;

{
/*
 * ->	Local variables
 */

int	nl;
struct stat	mbuf;

/*------*\
   Code
\*------*/

strcpy(Tftypes,"???");	/* Assume we can't determine file type */
mbuf = Inode;
/* Check if this is a file that should not be open
*/
switch (mbuf.st_mode & S_IFMT) {
	case S_IFCHR:	/* Charater special */
		strcpy(Tftypes,"csp");
		return(CHCTRSP);

	case S_IFBLK:	/* Block special */
		strcpy(Tftypes,"bsp");
		return(BLKSP);

	case S_IFIFO:	/* Fifo - pipe */
		strcpy(Tftypes,"pip");
		return(CHCTRSP);
#ifndef U11
	case S_IFSOCK:	/* Socket ! */
		strcpy(Tftypes,"soc");
		return(SOCKET);
#endif
}/*E switch mbuf.st_mode & S_IFMT */
if((ifile = fopen(file, "r")) == NULL) {
	PERROR "\n%s: %s %s\n", caller, CANTOPW, file);
	perror(caller);
	return(EOF);
}
switch (mbuf.st_mode & S_IFMT) {

	case S_IFLNK:	/* Symbolic link */
		strcpy(Tftypes,"sym");
		fclose(ifile);
		return(SYMLNK);

	case S_IFDIR:	/* Directory */
		strcpy(Tftypes,"dir");
		fclose(ifile);
		return(DIRECT);

}/*E switch mbuf.st_mode & S_IFMT */

/*
 *	Read in a MBUFSIZ amount of data from the file for
 *	further examination.
 */
if ((in = read(fileno(ifile), buf, MBUFSIZ)) <= 0)
    if (in < 0) {
	PERROR "\n%s: %s %s\n", caller, CANTRD, file);
	perror(caller);
	exit(FAIL);
    }
    else { 
	fclose(ifile);
	strcpy(Tftypes,"nul");
	return(EMPTY);	/* File appears to be empty */
    }
/*
 *	This check is looking for files that are used as output
 *	of ltf instead of using tape.  NOTE:  This is bogus as
 *	the rest of all these checks are.  This is the bare 
 *	minimum of checking.  Should check not only for VOL1,
 *	but also HDR1, etc., tape mark, then EOF1, etc., tape
 *	mark.  Thus this checks for VOL1 in the first 4 characters,
 *	and makes the file type binary.
 */
if (!strncmp(buf, "VOL1", 4)) {
	fclose(ifile);
	strcpy(Tftypes,"bin");
	return(BINARY);	/* Data file of some type */
}
switch(*(int *)buf) {

	case 0407:	/* Old impure Format on Ultrix-11 should
			 * be PDP-11 normal (I space only).
			 * On Ultrix-32 - seems to indicate
			 * a  .o  (object) file. */

		fclose(ifile);
#ifdef U11
		/* check to see if relocation info is stripped */
		if (((int *)buf)[7])
		    strcpy(Tftypes,"exe");
		else
#endif
		    strcpy(Tftypes,"bin");
		return(BINARY);

	case 0410:	/* Read-only/shared text */
	case 0413:	/* Demand Load Format */
#ifdef U11
	case 0401:	/* PDP-11 Standalone executable */
	case 0411:	/* PDP-11 Separated I & D */
	case 0430:	/* PDP-11 7 Overlays */
	case 0431:	/* PDP-11 7 Overlays */
	case 0450:	/* PDP-11 15 Overlays */
	case 0451:	/* PDP-11 15 Overlays */
#endif
		fclose(ifile);
		strcpy(Tftypes,"exe");
		return(BINARY);	

	case 0177555:	/* Very old archive */
	case 0177545:	/* Old archive */
		fclose(ifile);
		strcpy(Tftypes,"oar");
		return(BINARY);	

	case 070707:	/* CPIO data */
		fclose(ifile);
		strcpy(Tftypes,"cpi");
		return(CPIO);

}/*E switch(*(int *)buf) */

if(strncmp(buf, "!<arch>\n__.SYMDEF", 17) == 0 ) {

	fclose(ifile);
	strcpy(Tftypes,"arl");
	return(BINARY);	/* Archive Random Library */
}
if (strncmp(buf, "!<arch>\n", 8)==0) {

	fclose(ifile);
	strcpy(Tftypes,"arc");
	return(BINARY);	/* Archive */
}
if (mbuf.st_size % 512 == 0) {	/* it may be a PRESS file */
	lseek(fileno(ifile), -512L, 2);	/* last block */
	if ((in = read(fileno(ifile), buf, MBUFSIZ)) <= 0) {
	    if (in < 0) {
		PERROR "\n%s: %s %s\n", caller, CANTRD, file);
		perror(caller);
		exit(FAIL);
	    }
	} 
	if (in > 0 && *(int *)buf == 12138) {
		fclose(ifile);
		strcpy(Tftypes,"cmp");
		return(BINARY);	/* Press file ..*/
	}
}/*E if mbuf.st_size ..*/

/*
 * See if it looks like a command file.
 */
i = 0;
while(buf[i] == ' ' || buf[i] == '#' || buf[i] == '!') {
	while(buf[i++] != '\n')
		if(i >= in)	goto notcom;

}/*E while buf[i] ..*/

#if 0 /*for debugging*/
printf("\ngoing to lookupe \n");
for (x=i;x<i+80;x++)
  printf("%c",buf[x]);
#endif 0

if (lookupe(com)==1) {
	Type = TEXT;
	strcpy(Tftypes,"com");
	goto outa;
}

notcom:
i = 0;
if (!ccom()) {
	goto notc;
}

while(buf[i] == '#') {
	j = i;
	while(buf[i++] != '\n') {
		if(i - j > 255) {
			fclose(ifile);
			strcpy(Tftypes,"adf");
			return(BINARY);	/* Data file of some type */
		}
		if(i >= in) {
			goto notc;
		}
	}/* while buf[i++] ...*/

	if(!ccom()) {
		goto notc;
	}
}/*E while buf[i] ..*/

/*
 */
check:

if(lookupe(c) == 1) {
	while((ch = buf[i++]) != ';' && ch != '{') if(i >= in) {
		goto notc;
	}
	strcpy(Tftypes,"cc ");
	Type = TEXT;	/* 'C' program text */
	goto outa;

}/*E if lookupe(c) */

/* Look for newline or null character */
if (!strchr(buf, '\n')) {
	lseek(fileno(ifile), -512L, L_XTND);  /* last block */
	if ((in = read(fileno(ifile), buf, MBUFSIZ)) < 0) {
		PERROR "\n%s: %s %s\n", caller, CANTRD, file);
		perror(caller);
		exit(FAIL);
	} 
	if ((!strchr(buf, '\n')) || (!strchr(buf, '\0'))) {
		fclose(ifile);
		strcpy(Tftypes,"bin");
		return(BINARY);
	}
	else {
		/* Re-read the first bit of the file for the following tests */
		lseek(fileno(ifile), 0L, L_SET);  /* beginning of file */
		if ((in = read(fileno(ifile), buf, MBUFSIZ)) < 0) {
			PERROR "\n%s: %s %s\n", caller, CANTRD, file);
			perror(caller);
			exit(FAIL);
		}
	}
	
}

nl = 0;

while(buf[i] != '(') {
	if(buf[i] <= 0)
		goto notas;
	if(buf[i] == ';') {
		i++; 
		goto check; 
	}
	if(buf[i++] == '\n') {
		if(nl++ > NLM) {
			goto notc;
		}
		if(i >= in) {
			goto notc;
		}
 	}
}/*E while(buf[i] ..*/

while(buf[i] != ')') {
	if(buf[i++] == '\n')
		if(nl++ > NLM) {
			goto notc;
		}
		if(i >= in) {
			goto notc;
		}

}/*E while buf[i] ..*/

while(buf[i] != '{') {
	if(buf[i++] == '\n')
		if(nl++ > NLM) {
			goto notc;
		}
		if(i >= in) {
			goto notc;
		}

}/*E while buf[i] ..*/

strcpy(Tftypes,"cc ");
Type = TEXT;	/* 'C' program text */
goto outa;

/*
 */
notc:

i = 0;
while(buf[i] == 'c' || buf[i] == '#') {

	while(buf[i++] != '\n')
		if(i >= in)	goto notfort;

}/*E while buf[i] ..*/