rcsedit.c

早期freebsd实现

/*
 *                     RCS stream editor
 */
/**********************************************************************************
 *                       edits the input file according to a
 *                       script from stdin, generated by diff -n
 *                       performs keyword expansion
 **********************************************************************************
 */

/* Copyright (C) 1982, 1988, 1989 Walter Tichy
   Copyright 1990, 1991 by Paul Eggert
   Distributed under license by the Free Software Foundation, Inc.

This file is part of RCS.

RCS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

RCS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with RCS; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

Report problems and direct all questions to:

    [e-mail]

*/


/* $Log: rcsedit.c,v $
 * Revision 5.11  1991/11/03  01:11:44  eggert
 * Move the warning about link breaking to where they're actually being broken.
 *
 * Revision 5.10  1991/10/07  17:32:46  eggert
 * Support piece tables even if !has_mmap.  Fix rare NFS bugs.
 *
 * Revision 5.9  1991/09/17  19:07:40  eggert
 * SGI readlink() yields ENXIO, not EINVAL, for nonlinks.
 *
 * Revision 5.8  1991/08/19  03:13:55  eggert
 * Add piece tables, NFS bug workarounds.  Catch odd filenames.  Tune.
 *
 * Revision 5.7  1991/04/21  11:58:21  eggert
 * Fix errno bugs.  Add -x, RCSINIT, MS-DOS support.
 *
 * Revision 5.6  1991/02/25  07:12:40  eggert
 * Fix setuid bug.  Support new link behavior.  Work around broken "w+" fopen.
 *
 * Revision 5.5  1990/12/30  05:07:35  eggert
 * Fix report of busy RCS files when !defined(O_CREAT) | !defined(O_EXCL).
 *
 * Revision 5.4  1990/11/01  05:03:40  eggert
 * Permit arbitrary data in comment leaders.
 *
 * Revision 5.3  1990/09/11  02:41:13  eggert
 * Tune expandline().
 *
 * Revision 5.2  1990/09/04  08:02:21  eggert
 * Count RCS lines better.  Improve incomplete line handling.
 *
 * Revision 5.1  1990/08/29  07:13:56  eggert
 * Add -kkvl.
 * Fix bug when getting revisions to files ending in incomplete lines.
 * Fix bug in comment leader expansion.
 *
 * Revision 5.0  1990/08/22  08:12:47  eggert
 * Don't require final newline.
 * Don't append "checked in with -k by " to logs,
 * so that checking in a program with -k doesn't change it.
 * Don't generate trailing white space for empty comment leader.
 * Remove compile-time limits; use malloc instead.  Add -k, -V.
 * Permit dates past 1999/12/31.  Make lock and temp files faster and safer.
 * Ansify and Posixate.  Check diff's output.
 *
 * Revision 4.8  89/05/01  15:12:35  narten
 * changed copyright header to reflect current distribution rules
 * 
 * Revision 4.7  88/11/08  13:54:14  narten
 * misplaced semicolon caused infinite loop
 * 
 * Revision 4.6  88/08/09  19:12:45  eggert
 * Shrink stdio code size; allow cc -R.
 * 
 * Revision 4.5  87/12/18  11:38:46  narten
 * Changes from the 43. version. Don't know the significance of the
 * first change involving "rewind". Also, additional "lint" cleanup.
 * (Guy Harris)
 * 
 * Revision 4.4  87/10/18  10:32:21  narten
 * Updating version numbers. Changes relative to version 1.1 actually
 * relative to 4.1
 * 
 * Revision 1.4  87/09/24  13:59:29  narten
 * Sources now pass through lint (if you ignore printf/sprintf/fprintf 
 * warnings)
 * 
 * Revision 1.3  87/09/15  16:39:39  shepler
 * added an initializatin of the variables editline and linecorr
 * this will be done each time a file is processed.
 * (there was an obscure bug where if co was used to retrieve multiple files
 *  it would dump)
 * fix attributed to  Roy Morris @FileNet Corp ...!felix!roy
 * 
 * Revision 1.2  87/03/27  14:22:17  jenkins
 * Port to suns
 * 
 * Revision 4.1  83/05/12  13:10:30  wft
 * Added new markers Id and RCSfile; added locker to Header and Id.
 * Overhauled expandline completely() (problem with $01234567890123456789@).
 * Moved trymatch() and marker table to rcskeys.c.
 * 
 * Revision 3.7  83/05/12  13:04:39  wft
 * Added retry to expandline to resume after failed match which ended in $.
 * Fixed truncation problem for $19chars followed by@@.
 * Log no longer expands full path of RCS file.
 * 
 * Revision 3.6  83/05/11  16:06:30  wft
 * added retry to expandline to resume after failed match which ended in $.
 * Fixed truncation problem for $19chars followed by@@.
 * 
 * Revision 3.5  82/12/04  13:20:56  wft
 * Added expansion of keyword Locker.
 *
 * Revision 3.4  82/12/03  12:26:54  wft
 * Added line number correction in case editing does not start at the
 * beginning of the file.
 * Changed keyword expansion to always print a space before closing KDELIM;
 * Expansion for Header shortened.
 *
 * Revision 3.3  82/11/14  14:49:30  wft
 * removed Suffix from keyword expansion. Replaced fclose with ffclose.
 * keyreplace() gets log message from delta, not from curlogmsg.
 * fixed expression overflow in while(c=putc(GETC....
 * checked nil printing.
 *
 * Revision 3.2  82/10/18  21:13:39  wft
 * I added checks for write errors during the co process, and renamed
 * expandstring() to xpandstring().
 *
 * Revision 3.1  82/10/13  15:52:55  wft
 * changed type of result of getc() from char to int.
 * made keyword expansion loop in expandline() portable to machines
 * without sign-extension.
 */


#include "rcsbase.h"

libId(editId, "$Id: rcsedit.c,v 5.11 1991/11/03 01:11:44 eggert Exp $")

static void keyreplace P((enum markers,struct hshentry const*,FILE*));


FILE *fcopy;		 /* result file descriptor			    */
char const *resultfile;  /* result file name				    */
int locker_expansion;	 /* should the locker name be appended to Id val?   */
#if !large_memory
	static RILE *fedit; /* edit file descriptor */
	static char const *editfile; /* edit pathname */
#endif
static unsigned long editline; /* edit line counter; #lines before cursor   */
static long linecorr; /* #adds - #deletes in each edit run.		    */
               /*used to correct editline in case file is not rewound after */
               /* applying one delta                                        */

#define DIRTEMPNAMES 2
enum maker {notmade, real, effective};
struct buf dirtfname[DIRTEMPNAMES];		/* unlink these when done */
static enum maker volatile dirtfmaker[DIRTEMPNAMES];	/* if these are set */


#if has_NFS || bad_unlink
	int
un_link(s)
	char const *s;
/*
 * Remove S, even if it is unwritable.
 * Ignore unlink() ENOENT failures; NFS generates bogus ones.
 */
{
#	if bad_unlink
		int e;
		if (unlink(s) == 0)
			return 0;
		e = errno;
#		if has_NFS
			if (e == ENOENT)
				return 0;
#		endif
		if (chmod(s, S_IWUSR) != 0) {
			errno = e;
			return -1;
		}
#	endif
#	if has_NFS
		return unlink(s)==0 || errno==ENOENT  ?  0  :  -1;
#	else
		return unlink(s);
#	endif
}
#endif

#if !has_rename
#  if !has_NFS
#	define do_link(s,t) link(s,t)
#  else
	static int
do_link(s, t)
	char const *s, *t;
/* Link S to T, ignoring bogus EEXIST problems due to NFS failures.  */
{
	struct stat sb, tb;

	if (link(s,t) == 0)
		return 0;
	if (errno != EEXIST)
		return -1;
	if (
	    stat(s, &sb) == 0  &&
	    stat(t, &tb) == 0  &&
	    sb.st_ino == tb.st_ino  &&
	    sb.st_dev == tb.st_dev
	)
		return 0;
	errno = EEXIST;
	return -1;
}
#  endif
#endif


	static exiting void
editEndsPrematurely()
{
	fatserror("edit script ends prematurely");
}

	static exiting void
editLineNumberOverflow()
{
	fatserror("edit script refers to line past end of file");
}


#if large_memory

#if has_memmove
#	define movelines(s1, s2, n) VOID memmove(s1, s2, (n)*sizeof(Iptr_type))
#else
	static void
movelines(s1, s2, n)
	register Iptr_type *s1;
	register Iptr_type const *s2;
	register unsigned long n;
{
	if (s1 < s2)
		do {
			*s1++ = *s2++;
		} while (--n);
	else {
		s1 += n;
		s2 += n;
		do {
			*--s1 = *--s2;
		} while (--n);
	}
}
#endif

/*
 * `line' contains pointers to the lines in the currently `edited' file.
 * It is a 0-origin array that represents linelim-gapsize lines.
 * line[0..gap-1] and line[gap+gapsize..linelim-1] contain pointers to lines.
 * line[gap..gap+gapsize-1] contains garbage.
 *
 * Any @s in lines are duplicated.
 * Lines are terminated by \n, or (for a last partial line only) by single @.
 */
static Iptr_type *line;
static unsigned long gap, gapsize, linelim;


	static void
insertline(n, l)
	unsigned long n;
	Iptr_type l;
/* Before line N, insert line L.  N is 0-origin.  */
{
	if (linelim-gapsize < n)
	    editLineNumberOverflow();
	if (!gapsize)
	    line =
		!linelim ?
			tnalloc(Iptr_type, linelim = gapsize = 1024)
		: (
			gap = gapsize = linelim,
			trealloc(Iptr_type, line, linelim <<= 1)
		);
	if (n < gap)
	    movelines(line+n+gapsize, line+n, gap-n);
	else if (gap < n)
	    movelines(line+gap, line+gap+gapsize, n-gap);

	line[n] = l;
	gap = n + 1;
	gapsize--;
}

	static void
deletelines(n, nlines)
	unsigned long n, nlines;
/* Delete lines N through N+NLINES-1.  N is 0-origin.  */
{
	unsigned long l = n + nlines;
	if (linelim-gapsize < l  ||  l < n)
	    editLineNumberOverflow();
	if (l < gap)
	    movelines(line+l+gapsize, line+l, gap-l);
	else if (gap < n)
	    movelines(line+gap, line+gap+gapsize, n-gap);

	gap = n;
	gapsize += nlines;
}

	static void
snapshotline(f, l)
	register FILE *f;
	register Iptr_type l;
{
	register int c;
	do {
		if ((c = *l++) == SDELIM  &&  *l++ != SDELIM)
			return;
		aputc(c, f);
	} while (c != '\n');
}

	void
snapshotedit(f)
	FILE *f;
/* Copy the current state of the edits to F.  */
{
	register Iptr_type *p, *lim, *l=line;
	for (p=l, lim=l+gap;  p<lim;  )
		snapshotline(f, *p++);
	for (p+=gapsize, lim=l+linelim;  p<lim;  )
		snapshotline(f, *p++);
}

	static void
finisheditline(fin, fout, l, delta)
	RILE *fin;
	FILE *fout;
	Iptr_type l;
	struct hshentry const *delta;
{
	Iseek(fin, l);
	if (expandline(fin, fout, delta, true, (FILE*)0)  <  0)
		faterror("finisheditline internal error");
}

	void
finishedit(delta, outfile, done)
	struct hshentry const *delta;
	FILE *outfile;
	int done;
/*
 * Doing expansion if DELTA is set, output the state of the edits to OUTFILE.
 * But do nothing unless DONE is set (which means we are on the last pass).
 */
{
	if (done) {
		openfcopy(outfile);
		outfile = fcopy;
		if (!delta)
			snapshotedit(outfile);
		else {
			register Iptr_type *p, *lim, *l = line;
			register RILE *fin = finptr;
			Iptr_type here = Itell(fin);
			for (p=l, lim=l+gap;  p<lim;  )
				finisheditline(fin, outfile, *p++, delta);
			for (p+=gapsize, lim=l+linelim;  p<lim;  )
				finisheditline(fin, outfile, *p++, delta);
			Iseek(fin, here);
		}
	}
}

/* Open a temporary FILENAME for output, truncating any previous contents.  */
#   define fopen_update_truncate(filename) fopen(filename, FOPEN_W_WORK)
#else /* !large_memory */
    static FILE *
fopen_update_truncate(filename)
    char const *filename;
{
#	if bad_fopen_wplus
		if (un_link(filename) != 0)
			efaterror(filename);
#	endif
	return fopen(filename, FOPEN_WPLUS_WORK);
}
#endif


	void
openfcopy(f)
	FILE *f;
{
	if (!(fcopy = f)) {
		if (!resultfile)
			resultfile = maketemp(2);
		if (!(fcopy = fopen_update_truncate(resultfile)))
			efaterror(resultfile);
	}
}


#if !large_memory

	static void
swapeditfiles(outfile)
	FILE *outfile;
/* Function: swaps resultfile and editfile, assigns fedit=fcopy,
 * and rewinds fedit for reading.  Set fcopy to outfile if nonnull;
 * otherwise, set fcopy to be resultfile opened for reading and writing.
 */
{
	char const *tmpptr;

	editline = 0;  linecorr = 0;
	if (fseek(fcopy, 0L, SEEK_SET) != 0)
		Oerror();
	fedit = fcopy;
        tmpptr=editfile; editfile=resultfile; resultfile=tmpptr;
	openfcopy(outfile);
}

	void
snapshotedit(f)
	FILE *f;
/* Copy the current state of the edits to F.  */
{
	finishedit((struct hshentry *)nil, (FILE*)0, false);
	fastcopy(fedit, f);
	Irewind(fedit);
}

	void
finishedit(delta, outfile, done)
	struct hshentry const *delta;
	FILE *outfile;
	int done;
/* copy the rest of the edit file and close it (if it exists).
 * if delta!=nil, perform keyword substitution at the same time.
 * If DONE is set, we are finishing the last pass.
 */
{
	register RILE *fe;
	register FILE *fc;

	fe = fedit;
	if (fe) {
		fc = fcopy;
                if (delta!=nil) {
			while (1 < expandline(fe,fc,delta,false,(FILE*)0))
				;
                } else {
			fastcopy(fe,fc);
                }
		Ifclose(fe);
        }
	if (!done)
		swapeditfiles(outfile);
}
#endif



#if large_memory
#	define copylines(upto,delta) (editline = (upto))
#else
	static void
copylines(upto,delta)
	register unsigned long upto;
	struct hshentry const *delta;
/*
 * Copy input lines editline+1..upto from fedit to fcopy.
 * If delta != nil, keyword expansion is done simultaneously.
 * editline is updated. Rewinds a file only if necessary.
 */
{
	register int c;
	declarecache;
	register FILE *fc;
	register RILE *fe;

	if (upto < editline) {
                /* swap files */
		finishedit((struct hshentry *)nil, (FILE*)0, false);
                /* assumes edit only during last pass, from the beginning*/
        }
	fe = fedit;
	fc = fcopy;
	if (editline < upto)
	    if (delta)
		do {
			if (expandline(fe,fc,delta,false,(FILE*)0) <= 1)
				editLineNumberOverflow();
		} while (++editline < upto);
	    else {
		setupcache(fe); cache(fe);
		do {
			do {
				cachegeteof(c, editLineNumberOverflow(););
				aputc(c, fc);
			} while (c != '\n');
		} while (++editline < upto);
		uncache(fe);
	    }
}
#endif



	void
xpandstring(delta)
	struct hshentry const *delta;
/* Function: Reads a string terminated by SDELIM from finptr and writes it
 * to fcopy. Double SDELIM is replaced with single SDELIM.
 * Keyword expansion is performed with data from delta.
 * If foutptr is nonnull, the string is also copied unchanged to foutptr.
 */
{
	while (1 < expandline(finptr,fcopy,delta,true,foutptr))
		;
}


	void
copystring()
/* Function: copies a string terminated with a single SDELIM from finptr to
 * fcopy, replacing all double SDELIM with a single SDELIM.
 * If foutptr is nonnull, the string also copied unchanged to foutptr.