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IABSD.fr/src/usr.bin/cvs/rcs.c

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  • Author : deraadt
    Date : 2019-06-28 13:34:58
    Hash : 3aaa63eb
    Message : When system calls indicate an error they return -1, not some arbitrary value < 0. errno is only updated in this case. Change all (most?) callers of syscalls to follow this better, and let's see if this strictness helps us in the future.

  • usr.bin/cvs/rcs.c
  • /*	$OpenBSD: rcs.c,v 1.319 2019/06/28 13:35:00 deraadt Exp $	*/
    /*
     * Copyright (c) 2004 Jean-Francois Brousseau <jfb@openbsd.org>
     * All rights reserved.
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     *
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. The name of the author may not be used to endorse or promote products
     *    derived from this software without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
     * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
     * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
     * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     * EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
     * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
     * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     */
    
    #include <sys/stat.h>
    
    #include <ctype.h>
    #include <errno.h>
    #include <libgen.h>
    #include <pwd.h>
    #include <stdlib.h>
    #include <string.h>
    #include <unistd.h>
    
    #include "atomicio.h"
    #include "cvs.h"
    #include "diff.h"
    #include "rcs.h"
    #include "rcsparse.h"
    
    #define MINIMUM(a, b)	(((a) < (b)) ? (a) : (b))
    
    #define RCS_KWEXP_SIZE  1024
    
    #define ANNOTATE_NEVER	0
    #define ANNOTATE_NOW	1
    #define ANNOTATE_LATER	2
    
    /* invalid characters in RCS symbol names */
    static const char rcs_sym_invch[] = RCS_SYM_INVALCHAR;
    
    /* comment leaders, depending on the file's suffix */
    static const struct rcs_comment {
    	const char	*rc_suffix;
    	const char	*rc_cstr;
    } rcs_comments[] = {
    	{ "1",    ".\\\" " },
    	{ "2",    ".\\\" " },
    	{ "3",    ".\\\" " },
    	{ "4",    ".\\\" " },
    	{ "5",    ".\\\" " },
    	{ "6",    ".\\\" " },
    	{ "7",    ".\\\" " },
    	{ "8",    ".\\\" " },
    	{ "9",    ".\\\" " },
    	{ "a",    "-- "    },	/* Ada		 */
    	{ "ada",  "-- "    },
    	{ "adb",  "-- "    },
    	{ "asm",  ";; "    },	/* assembler (MS-DOS) */
    	{ "ads",  "-- "    },	/* Ada */
    	{ "bat",  ":: "    },	/* batch (MS-DOS) */
    	{ "body", "-- "    },	/* Ada */
    	{ "c",    " * "    },	/* C */
    	{ "c++",  "// "    },	/* C++ */
    	{ "cc",   "// "    },
    	{ "cpp",  "// "    },
    	{ "cxx",  "// "    },
    	{ "m",    "// "    },	/* Objective-C */
    	{ "cl",   ";;; "   },	/* Common Lisp	 */
    	{ "cmd",  ":: "    },	/* command (OS/2) */
    	{ "cmf",  "c "     },	/* CM Fortran	 */
    	{ "csh",  "# "     },	/* shell	 */
    	{ "e",    "# "     },	/* efl		 */
    	{ "epsf", "% "     },	/* encapsulated postscript */
    	{ "epsi", "% "     },	/* encapsulated postscript */
    	{ "el",   "; "     },	/* Emacs Lisp	 */
    	{ "f",    "c "     },	/* Fortran	 */
    	{ "for",  "c "     },
    	{ "h",    " * "    },	/* C-header	 */
    	{ "hh",   "// "    },	/* C++ header	 */
    	{ "hpp",  "// "    },
    	{ "hxx",  "// "    },
    	{ "in",   "# "     },	/* for Makefile.in */
    	{ "l",    " * "    },	/* lex */
    	{ "mac",  ";; "    },	/* macro (DEC-10, MS-DOS, PDP-11, VMS, etc) */
    	{ "mak",  "# "     },	/* makefile, e.g. Visual C++ */
    	{ "me",   ".\\\" " },	/* me-macros	t/nroff	 */
    	{ "ml",   "; "     },	/* mocklisp	 */
    	{ "mm",   ".\\\" " },	/* mm-macros	t/nroff	 */
    	{ "ms",   ".\\\" " },	/* ms-macros	t/nroff	 */
    	{ "man",  ".\\\" " },	/* man-macros	t/nroff	 */
    	{ "p",    " * "    },	/* pascal	 */
    	{ "pas",  " * "    },
    	{ "pl",   "# "     },	/* Perl	(conflict with Prolog) */
    	{ "pm",   "# "     },	/* Perl	module */
    	{ "ps",   "% "     },	/* postscript */
    	{ "psw",  "% "     },	/* postscript wrap */
    	{ "pswm", "% "     },	/* postscript wrap */
    	{ "r",    "# "     },	/* ratfor	 */
    	{ "rc",   " * "    },	/* Microsoft Windows resource file */
    	{ "red",  "% "     },	/* psl/rlisp	 */
    	{ "sh",   "# "     },	/* shell	 */
    	{ "sl",   "% "     },	/* psl		 */
    	{ "spec", "-- "    },	/* Ada		 */
    	{ "tex",  "% "     },	/* tex		 */
    	{ "y",    " * "    },	/* yacc		 */
    	{ "ye",   " * "    },	/* yacc-efl	 */
    	{ "yr",   " * "    },	/* yacc-ratfor	 */
    };
    
    struct rcs_kw rcs_expkw[] =  {
    	{ "Author",	RCS_KW_AUTHOR   },
    	{ "Date",	RCS_KW_DATE     },
    	{ "Header",	RCS_KW_HEADER   },
    	{ "Id",		RCS_KW_ID       },
    	{ "Locker",	RCS_KW_LOCKER	},
    	{ "Log",	RCS_KW_LOG      },
    	{ "Name",	RCS_KW_NAME     },
    	{ "RCSfile",	RCS_KW_RCSFILE  },
    	{ "Revision",	RCS_KW_REVISION },
    	{ "Source",	RCS_KW_SOURCE   },
    	{ "State",	RCS_KW_STATE    },
    	{ "Mdocdate",	RCS_KW_MDOCDATE },
    };
    
    #define NB_COMTYPES	(sizeof(rcs_comments)/sizeof(rcs_comments[0]))
    
    static RCSNUM	*rcs_get_revision(const char *, RCSFILE *);
    int		rcs_patch_lines(struct rcs_lines *, struct rcs_lines *,
    		    struct rcs_line **, struct rcs_delta *);
    static void	rcs_freedelta(struct rcs_delta *);
    static void	rcs_strprint(const u_char *, size_t, FILE *);
    
    static void	rcs_kwexp_line(char *, struct rcs_delta *, struct rcs_lines *,
    		    struct rcs_line *, int mode);
    
    /*
     * Prepare RCSFILE for parsing. The given file descriptor (if any) must be
     * read-only and is closed on rcs_close().
     */
    RCSFILE *
    rcs_open(const char *path, int fd, int flags, ...)
    {
    	int mode;
    	mode_t fmode;
    	RCSFILE *rfp;
    	va_list vap;
    	struct stat st;
    	struct rcs_delta *rdp;
    	struct rcs_lock *lkr;
    
    	fmode = S_IRUSR|S_IRGRP|S_IROTH;
    	flags &= 0xffff;	/* ditch any internal flags */
    
    	if (flags & RCS_CREATE) {
    		va_start(vap, flags);
    		mode = va_arg(vap, int);
    		va_end(vap);
    		fmode = (mode_t)mode;
    	} else {
    		if (fstat(fd, &st) == -1)
    			fatal("rcs_open: %s: fstat: %s", path, strerror(errno));
    		fmode = st.st_mode;
    	}
    
    	fmode &= ~cvs_umask;
    
    	rfp = xcalloc(1, sizeof(*rfp));
    
    	rfp->rf_path = xstrdup(path);
    	rfp->rf_flags = flags | RCS_SLOCK | RCS_SYNCED;
    	rfp->rf_mode = fmode;
    	if (fd == -1)
    		rfp->rf_file = NULL;
    	else if ((rfp->rf_file = fdopen(fd, "r")) == NULL)
    		fatal("rcs_open: %s: fdopen: %s", path, strerror(errno));
    	rfp->rf_dead = 0;
    
    	TAILQ_INIT(&(rfp->rf_delta));
    	TAILQ_INIT(&(rfp->rf_access));
    	TAILQ_INIT(&(rfp->rf_symbols));
    	TAILQ_INIT(&(rfp->rf_locks));
    
    	if (!(rfp->rf_flags & RCS_CREATE)) {
    		if (rcsparse_init(rfp))
    			fatal("could not parse admin data");
    	}
    
    	/* fill in rd_locker */
    	TAILQ_FOREACH(lkr, &(rfp->rf_locks), rl_list) {
    		if ((rdp = rcs_findrev(rfp, lkr->rl_num)) == NULL) {
    			rcs_close(rfp);
    			return (NULL);
    		}
    
    		rdp->rd_locker = xstrdup(lkr->rl_name);
    	}
    
    	return (rfp);
    }
    
    /*
     * rcs_close()
     *
     * Close an RCS file handle.
     */
    void
    rcs_close(RCSFILE *rfp)
    {
    	struct rcs_delta *rdp;
    	struct rcs_access *rap;
    	struct rcs_lock *rlp;
    	struct rcs_sym *rsp;
    
    	if ((rfp->rf_flags & RCS_WRITE) && !(rfp->rf_flags & RCS_SYNCED))
    		rcs_write(rfp);
    
    	while (!TAILQ_EMPTY(&(rfp->rf_delta))) {
    		rdp = TAILQ_FIRST(&(rfp->rf_delta));
    		TAILQ_REMOVE(&(rfp->rf_delta), rdp, rd_list);
    		rcs_freedelta(rdp);
    	}
    
    	while (!TAILQ_EMPTY(&(rfp->rf_access))) {
    		rap = TAILQ_FIRST(&(rfp->rf_access));
    		TAILQ_REMOVE(&(rfp->rf_access), rap, ra_list);
    		free(rap->ra_name);
    		free(rap);
    	}
    
    	while (!TAILQ_EMPTY(&(rfp->rf_symbols))) {
    		rsp = TAILQ_FIRST(&(rfp->rf_symbols));
    		TAILQ_REMOVE(&(rfp->rf_symbols), rsp, rs_list);
    		free(rsp->rs_num);
    		free(rsp->rs_name);
    		free(rsp);
    	}
    
    	while (!TAILQ_EMPTY(&(rfp->rf_locks))) {
    		rlp = TAILQ_FIRST(&(rfp->rf_locks));
    		TAILQ_REMOVE(&(rfp->rf_locks), rlp, rl_list);
    		free(rlp->rl_num);
    		free(rlp->rl_name);
    		free(rlp);
    	}
    
    	free(rfp->rf_head);
    	free(rfp->rf_branch);
    
    	if (rfp->rf_file != NULL)
    		fclose(rfp->rf_file);
    	free(rfp->rf_path);
    	free(rfp->rf_comment);
    	free(rfp->rf_expand);
    	free(rfp->rf_desc);
    	if (rfp->rf_pdata != NULL)
    		rcsparse_free(rfp);
    	free(rfp);
    }
    
    /*
     * rcs_write()
     *
     * Write the contents of the RCS file handle <rfp> to disk in the file whose
     * path is in <rf_path>.
     */
    void
    rcs_write(RCSFILE *rfp)
    {
    	FILE *fp;
    	char   numbuf[CVS_REV_BUFSZ], *fn, tmpdir[PATH_MAX];
    	struct rcs_access *ap;
    	struct rcs_sym *symp;
    	struct rcs_branch *brp;
    	struct rcs_delta *rdp;
    	struct rcs_lock *lkp;
    	size_t len;
    	int fd, saved_errno;
    
    	fd = -1;
    
    	if (rfp->rf_flags & RCS_SYNCED)
    		return;
    
    	if (cvs_noexec == 1)
    		return;
    
    	/* Write operations need the whole file parsed */
    	if (rcsparse_deltatexts(rfp, NULL))
    		fatal("rcs_write: rcsparse_deltatexts");
    
    	if (strlcpy(tmpdir, rfp->rf_path, sizeof(tmpdir)) >= sizeof(tmpdir))
    		fatal("rcs_write: truncation");
    	(void)xasprintf(&fn, "%s/rcs.XXXXXXXXXX", dirname(tmpdir));
    
    	if ((fd = mkstemp(fn)) == -1)
    		fatal("%s", fn);
    
    	if ((fp = fdopen(fd, "w")) == NULL) {
    		saved_errno = errno;
    		(void)unlink(fn);
    		fatal("fdopen %s: %s", fn, strerror(saved_errno));
    	}
    
    	worklist_add(fn, &temp_files);
    
    	if (rfp->rf_head != NULL)
    		rcsnum_tostr(rfp->rf_head, numbuf, sizeof(numbuf));
    	else
    		numbuf[0] = '\0';
    
    	fprintf(fp, "head\t%s;\n", numbuf);
    
    	if (rfp->rf_branch != NULL) {
    		rcsnum_tostr(rfp->rf_branch, numbuf, sizeof(numbuf));
    		fprintf(fp, "branch\t%s;\n", numbuf);
    	}
    
    	fputs("access", fp);
    	TAILQ_FOREACH(ap, &(rfp->rf_access), ra_list) {
    		fprintf(fp, "\n\t%s", ap->ra_name);
    	}
    	fputs(";\n", fp);
    
    	fprintf(fp, "symbols");
    	TAILQ_FOREACH(symp, &(rfp->rf_symbols), rs_list) {
    		if (RCSNUM_ISBRANCH(symp->rs_num))
    			rcsnum_addmagic(symp->rs_num);
    		rcsnum_tostr(symp->rs_num, numbuf, sizeof(numbuf));
    		fprintf(fp, "\n\t%s:%s", symp->rs_name, numbuf);
    	}
    	fprintf(fp, ";\n");
    
    	fprintf(fp, "locks");
    	TAILQ_FOREACH(lkp, &(rfp->rf_locks), rl_list) {
    		rcsnum_tostr(lkp->rl_num, numbuf, sizeof(numbuf));
    		fprintf(fp, "\n\t%s:%s", lkp->rl_name, numbuf);
    	}
    
    	fprintf(fp, ";");
    
    	if (rfp->rf_flags & RCS_SLOCK)
    		fprintf(fp, " strict;");
    	fputc('\n', fp);
    
    	fputs("comment\t@", fp);
    	if (rfp->rf_comment != NULL) {
    		rcs_strprint((const u_char *)rfp->rf_comment,
    		    strlen(rfp->rf_comment), fp);
    		fputs("@;\n", fp);
    	} else
    		fputs("# @;\n", fp);
    
    	if (rfp->rf_expand != NULL) {
    		fputs("expand @", fp);
    		rcs_strprint((const u_char *)rfp->rf_expand,
    		    strlen(rfp->rf_expand), fp);
    		fputs("@;\n", fp);
    	}
    
    	fputs("\n\n", fp);
    
    	TAILQ_FOREACH(rdp, &(rfp->rf_delta), rd_list) {
    		fprintf(fp, "%s\n", rcsnum_tostr(rdp->rd_num, numbuf,
    		    sizeof(numbuf)));
    		fprintf(fp, "date\t%d.%02d.%02d.%02d.%02d.%02d;",
    		    rdp->rd_date.tm_year + 1900, rdp->rd_date.tm_mon + 1,
    		    rdp->rd_date.tm_mday, rdp->rd_date.tm_hour,
    		    rdp->rd_date.tm_min, rdp->rd_date.tm_sec);
    		fprintf(fp, "\tauthor %s;\tstate %s;\n",
    		    rdp->rd_author, rdp->rd_state);
    		fputs("branches", fp);
    		TAILQ_FOREACH(brp, &(rdp->rd_branches), rb_list) {
    			fprintf(fp, "\n\t%s", rcsnum_tostr(brp->rb_num, numbuf,
    			    sizeof(numbuf)));
    		}
    		fputs(";\n", fp);
    		fprintf(fp, "next\t%s;\n\n", rcsnum_tostr(rdp->rd_next,
    		    numbuf, sizeof(numbuf)));
    	}
    
    	fputs("\ndesc\n@", fp);
    	if (rfp->rf_desc != NULL && (len = strlen(rfp->rf_desc)) > 0) {
    		rcs_strprint((const u_char *)rfp->rf_desc, len, fp);
    		if (rfp->rf_desc[len-1] != '\n')
    			fputc('\n', fp);
    	}
    	fputs("@\n", fp);
    
    	/* deltatexts */
    	TAILQ_FOREACH(rdp, &(rfp->rf_delta), rd_list) {
    		fprintf(fp, "\n\n%s\n", rcsnum_tostr(rdp->rd_num, numbuf,
    		    sizeof(numbuf)));
    		fputs("log\n@", fp);
    		if (rdp->rd_log != NULL) {
    			len = strlen(rdp->rd_log);
    			rcs_strprint((const u_char *)rdp->rd_log, len, fp);
    			if (len == 0 || rdp->rd_log[len-1] != '\n')
    				fputc('\n', fp);
    		}
    		fputs("@\ntext\n@", fp);
    		if (rdp->rd_text != NULL)
    			rcs_strprint(rdp->rd_text, rdp->rd_tlen, fp);
    		fputs("@\n", fp);
    	}
    
    	if (fchmod(fd, rfp->rf_mode) == -1) {
    		saved_errno = errno;
    		(void)unlink(fn);
    		fatal("fchmod %s: %s", fn, strerror(saved_errno));
    	}
    
    	(void)fclose(fp);
    
    	if (rename(fn, rfp->rf_path) == -1) {
    		saved_errno = errno;
    		(void)unlink(fn);
    		fatal("rename(%s, %s): %s", fn, rfp->rf_path,
    		    strerror(saved_errno));
    	}
    
    	rfp->rf_flags |= RCS_SYNCED;
    	free(fn);
    }
    
    /*
     * rcs_head_get()
     *
     * Retrieve the revision number of the head revision for the RCS file <file>.
     */
    RCSNUM *
    rcs_head_get(RCSFILE *file)
    {
    	struct rcs_branch *brp;
    	struct rcs_delta *rdp;
    	RCSNUM *rev, *rootrev;
    
    	if (file->rf_head == NULL)
    		return NULL;
    
    	rev = rcsnum_alloc();
    	if (file->rf_branch != NULL) {
    		/* we have a default branch, use that to calculate the
    		 * real HEAD*/
    		rootrev = rcsnum_alloc();
    		rcsnum_cpy(file->rf_branch, rootrev,
    		    file->rf_branch->rn_len - 1);
    		if ((rdp = rcs_findrev(file, rootrev)) == NULL)
    			fatal("rcs_head_get: could not find root revision");
    
    		/* HEAD should be the last revision on the default branch */
    		TAILQ_FOREACH(brp, &(rdp->rd_branches), rb_list) {
    			if (rcsnum_cmp(brp->rb_num, file->rf_branch,
    			    file->rf_branch->rn_len) == 0)
    				break;
    		}
    		free(rootrev);
    
    		if (brp == NULL)
    			fatal("rcs_head_get: could not find first default "
    			    "branch revision");
    
    		if ((rdp = rcs_findrev(file, brp->rb_num)) == NULL)
    			fatal("rcs_head_get: could not find branch revision");
    		while (rdp->rd_next->rn_len != 0)
    			if ((rdp = rcs_findrev(file, rdp->rd_next)) == NULL)
    				fatal("rcs_head_get: could not find "
    				    "next branch revision");
    
    		rcsnum_cpy(rdp->rd_num, rev, 0);
    	} else {
    		rcsnum_cpy(file->rf_head, rev, 0);
    	}
    
    	return (rev);
    }
    
    /*
     * rcs_head_set()
     *
     * Set the revision number of the head revision for the RCS file <file> to
     * <rev>, which must reference a valid revision within the file.
     */
    int
    rcs_head_set(RCSFILE *file, RCSNUM *rev)
    {
    	if (rcs_findrev(file, rev) == NULL)
    		return (-1);
    
    	if (file->rf_head == NULL)
    		file->rf_head = rcsnum_alloc();
    
    	rcsnum_cpy(rev, file->rf_head, 0);
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_branch_new()
     *
     * Create a new branch out of supplied revision for the RCS file <file>.
     */
    RCSNUM *
    rcs_branch_new(RCSFILE *file, RCSNUM *rev)
    {
    	RCSNUM *brev;
    	struct rcs_sym *sym;
    
    	if ((brev = rcsnum_new_branch(rev)) == NULL)
    		return (NULL);
    
    	for (;;) {
    		TAILQ_FOREACH(sym, &(file->rf_symbols), rs_list)
    			if (!rcsnum_cmp(sym->rs_num, brev, 0))
    				break;
    
    		if (sym == NULL)
    			break;
    
    		if (rcsnum_inc(brev) == NULL ||
    		    rcsnum_inc(brev) == NULL) {
    			free(brev);
    			return (NULL);
    		}
    	}
    
    	return (brev);
    }
    
    /*
     * rcs_branch_get()
     *
     * Retrieve the default branch number for the RCS file <file>.
     * Returns the number on success.  If NULL is returned, then there is no
     * default branch for this file.
     */
    const RCSNUM *
    rcs_branch_get(RCSFILE *file)
    {
    	return (file->rf_branch);
    }
    
    /*
     * rcs_branch_set()
     *
     * Set the default branch for the RCS file <file> to <bnum>.
     * Returns 0 on success, -1 on failure.
     */
    int
    rcs_branch_set(RCSFILE *file, const RCSNUM *bnum)
    {
    	if (file->rf_branch == NULL)
    		file->rf_branch = rcsnum_alloc();
    
    	rcsnum_cpy(bnum, file->rf_branch, 0);
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_access_add()
     *
     * Add the login name <login> to the access list for the RCS file <file>.
     * Returns 0 on success, or -1 on failure.
     */
    int
    rcs_access_add(RCSFILE *file, const char *login)
    {
    	struct rcs_access *ap;
    
    	/* first look for duplication */
    	TAILQ_FOREACH(ap, &(file->rf_access), ra_list) {
    		if (strcmp(ap->ra_name, login) == 0)
    			return (-1);
    	}
    
    	ap = xmalloc(sizeof(*ap));
    	ap->ra_name = xstrdup(login);
    	TAILQ_INSERT_TAIL(&(file->rf_access), ap, ra_list);
    
    	/* not synced anymore */
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_access_remove()
     *
     * Remove an entry with login name <login> from the access list of the RCS
     * file <file>.
     * Returns 0 on success, or -1 on failure.
     */
    int
    rcs_access_remove(RCSFILE *file, const char *login)
    {
    	struct rcs_access *ap;
    
    	TAILQ_FOREACH(ap, &(file->rf_access), ra_list)
    		if (strcmp(ap->ra_name, login) == 0)
    			break;
    
    	if (ap == NULL)
    		return (-1);
    
    	TAILQ_REMOVE(&(file->rf_access), ap, ra_list);
    	free(ap->ra_name);
    	free(ap);
    
    	/* not synced anymore */
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_sym_add()
     *
     * Add a symbol to the list of symbols for the RCS file <rfp>.  The new symbol
     * is named <sym> and is bound to the RCS revision <snum>.
     */
    int
    rcs_sym_add(RCSFILE *rfp, const char *sym, RCSNUM *snum)
    {
    	struct rcs_sym *symp;
    
    	if (!rcs_sym_check(sym))
    		return (-1);
    
    	/* first look for duplication */
    	TAILQ_FOREACH(symp, &(rfp->rf_symbols), rs_list) {
    		if (strcmp(symp->rs_name, sym) == 0)
    			return (1);
    	}
    
    	symp = xmalloc(sizeof(*symp));
    	symp->rs_name = xstrdup(sym);
    	symp->rs_num = rcsnum_alloc();
    	rcsnum_cpy(snum, symp->rs_num, 0);
    
    	TAILQ_INSERT_HEAD(&(rfp->rf_symbols), symp, rs_list);
    
    	/* not synced anymore */
    	rfp->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_sym_remove()
     *
     * Remove the symbol with name <sym> from the symbol list for the RCS file
     * <file>.  If no such symbol is found, the call fails and returns with an
     * error.
     * Returns 0 on success, or -1 on failure.
     */
    int
    rcs_sym_remove(RCSFILE *file, const char *sym)
    {
    	struct rcs_sym *symp;
    
    	if (!rcs_sym_check(sym))
    		return (-1);
    
    	TAILQ_FOREACH(symp, &(file->rf_symbols), rs_list)
    		if (strcmp(symp->rs_name, sym) == 0)
    			break;
    
    	if (symp == NULL)
    		return (-1);
    
    	TAILQ_REMOVE(&(file->rf_symbols), symp, rs_list);
    	free(symp->rs_name);
    	free(symp->rs_num);
    	free(symp);
    
    	/* not synced anymore */
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_sym_get()
     *
     * Find a specific symbol <sym> entry in the tree of the RCS file <file>.
     *
     * Returns a pointer to the symbol on success, or NULL on failure.
     */
    struct rcs_sym *
    rcs_sym_get(RCSFILE *file, const char *sym)
    {
    	struct rcs_sym *symp;
    
    	TAILQ_FOREACH(symp, &(file->rf_symbols), rs_list)
    		if (strcmp(symp->rs_name, sym) == 0)
    			return (symp);
    
    	return (NULL);
    }
    
    /*
     * rcs_sym_getrev()
     *
     * Retrieve the RCS revision number associated with the symbol <sym> for the
     * RCS file <file>.  The returned value is a dynamically-allocated copy and
     * should be freed by the caller once they are done with it.
     * Returns the RCSNUM on success, or NULL on failure.
     */
    RCSNUM *
    rcs_sym_getrev(RCSFILE *file, const char *sym)
    {
    	RCSNUM *num;
    	struct rcs_sym *symp;
    
    	if (!rcs_sym_check(sym) || file->rf_head == NULL)
    		return (NULL);
    
    	if (!strcmp(sym, RCS_HEAD_BRANCH)) {
    		num = rcsnum_alloc();
    		rcsnum_cpy(file->rf_head, num, 0);
    		return (num);
    	}
    
    	num = NULL;
    	TAILQ_FOREACH(symp, &(file->rf_symbols), rs_list)
    		if (strcmp(symp->rs_name, sym) == 0)
    			break;
    
    	if (symp != NULL) {
    		num = rcsnum_alloc();
    		rcsnum_cpy(symp->rs_num, num, 0);
    	}
    
    	return (num);
    }
    
    /*
     * rcs_sym_check()
     *
     * Check the RCS symbol name <sym> for any unsupported characters.
     * Returns 1 if the tag is correct, 0 if it isn't valid.
     */
    int
    rcs_sym_check(const char *sym)
    {
    	int ret;
    	const unsigned char *cp;
    
    	ret = 1;
    	cp = sym;
    	if (!isalpha(*cp++))
    		return (0);
    
    	for (; *cp != '\0'; cp++)
    		if (!isgraph(*cp) || (strchr(rcs_sym_invch, *cp) != NULL)) {
    			ret = 0;
    			break;
    		}
    
    	return (ret);
    }
    
    /*
     * rcs_lock_getmode()
     *
     * Retrieve the locking mode of the RCS file <file>.
     */
    int
    rcs_lock_getmode(RCSFILE *file)
    {
    	return (file->rf_flags & RCS_SLOCK) ? RCS_LOCK_STRICT : RCS_LOCK_LOOSE;
    }
    
    /*
     * rcs_lock_setmode()
     *
     * Set the locking mode of the RCS file <file> to <mode>, which must either
     * be RCS_LOCK_LOOSE or RCS_LOCK_STRICT.
     * Returns the previous mode on success, or -1 on failure.
     */
    int
    rcs_lock_setmode(RCSFILE *file, int mode)
    {
    	int pmode;
    	pmode = rcs_lock_getmode(file);
    
    	if (mode == RCS_LOCK_STRICT)
    		file->rf_flags |= RCS_SLOCK;
    	else if (mode == RCS_LOCK_LOOSE)
    		file->rf_flags &= ~RCS_SLOCK;
    	else
    		fatal("rcs_lock_setmode: invalid mode `%d'", mode);
    
    	file->rf_flags &= ~RCS_SYNCED;
    	return (pmode);
    }
    
    /*
     * rcs_lock_add()
     *
     * Add an RCS lock for the user <user> on revision <rev>.
     * Returns 0 on success, or -1 on failure.
     */
    int
    rcs_lock_add(RCSFILE *file, const char *user, RCSNUM *rev)
    {
    	struct rcs_lock *lkp;
    
    	/* first look for duplication */
    	TAILQ_FOREACH(lkp, &(file->rf_locks), rl_list) {
    		if (strcmp(lkp->rl_name, user) == 0 &&
    		    rcsnum_cmp(rev, lkp->rl_num, 0) == 0)
    			return (-1);
    	}
    
    	lkp = xmalloc(sizeof(*lkp));
    	lkp->rl_name = xstrdup(user);
    	lkp->rl_num = rcsnum_alloc();
    	rcsnum_cpy(rev, lkp->rl_num, 0);
    
    	TAILQ_INSERT_TAIL(&(file->rf_locks), lkp, rl_list);
    
    	/* not synced anymore */
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    
    /*
     * rcs_lock_remove()
     *
     * Remove the RCS lock on revision <rev>.
     * Returns 0 on success, or -1 on failure.
     */
    int
    rcs_lock_remove(RCSFILE *file, const char *user, RCSNUM *rev)
    {
    	struct rcs_lock *lkp;
    
    	TAILQ_FOREACH(lkp, &(file->rf_locks), rl_list) {
    		if (strcmp(lkp->rl_name, user) == 0 &&
    		    rcsnum_cmp(lkp->rl_num, rev, 0) == 0)
    			break;
    	}
    
    	if (lkp == NULL)
    		return (-1);
    
    	TAILQ_REMOVE(&(file->rf_locks), lkp, rl_list);
    	free(lkp->rl_num);
    	free(lkp->rl_name);
    	free(lkp);
    
    	/* not synced anymore */
    	file->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    
    /*
     * rcs_desc_get()
     *
     * Retrieve the description for the RCS file <file>.
     */
    const char *
    rcs_desc_get(RCSFILE *file)
    {
    	return (file->rf_desc);
    }
    
    /*
     * rcs_desc_set()
     *
     * Set the description for the RCS file <file>.
     */
    void
    rcs_desc_set(RCSFILE *file, const char *desc)
    {
    	char *tmp;
    
    	tmp = xstrdup(desc);
    	free(file->rf_desc);
    	file->rf_desc = tmp;
    	file->rf_flags &= ~RCS_SYNCED;
    }
    
    /*
     * rcs_comment_lookup()
     *
     * Lookup the assumed comment leader based on a file's suffix.
     * Returns a pointer to the string on success, or NULL on failure.
     */
    const char *
    rcs_comment_lookup(const char *filename)
    {
    	int i;
    	const char *sp;
    
    	if ((sp = strrchr(filename, '.')) == NULL)
    		return (NULL);
    	sp++;
    
    	for (i = 0; i < (int)NB_COMTYPES; i++)
    		if (strcmp(rcs_comments[i].rc_suffix, sp) == 0)
    			return (rcs_comments[i].rc_cstr);
    	return (NULL);
    }
    
    /*
     * rcs_comment_get()
     *
     * Retrieve the comment leader for the RCS file <file>.
     */
    const char *
    rcs_comment_get(RCSFILE *file)
    {
    	return (file->rf_comment);
    }
    
    /*
     * rcs_comment_set()
     *
     * Set the comment leader for the RCS file <file>.
     */
    void
    rcs_comment_set(RCSFILE *file, const char *comment)
    {
    	char *tmp;
    
    	tmp = xstrdup(comment);
    	free(file->rf_comment);
    	file->rf_comment = tmp;
    	file->rf_flags &= ~RCS_SYNCED;
    }
    
    int
    rcs_patch_lines(struct rcs_lines *dlines, struct rcs_lines *plines,
        struct rcs_line **alines, struct rcs_delta *rdp)
    {
    	u_char op;
    	char *ep;
    	struct rcs_line *lp, *dlp, *ndlp;
    	int i, lineno, nbln;
    	u_char tmp;
    
    	dlp = TAILQ_FIRST(&(dlines->l_lines));
    	lp = TAILQ_FIRST(&(plines->l_lines));
    
    	/* skip first bogus line */
    	for (lp = TAILQ_NEXT(lp, l_list); lp != NULL;
    	    lp = TAILQ_NEXT(lp, l_list)) {
    		if (lp->l_len < 2)
    			fatal("line too short, RCS patch seems broken");
    		op = *(lp->l_line);
    		/* NUL-terminate line buffer for strtol() safety. */
    		tmp = lp->l_line[lp->l_len - 1];
    		lp->l_line[lp->l_len - 1] = '\0';
    		lineno = (int)strtol((char*)(lp->l_line + 1), &ep, 10);
    		if (lineno - 1 > dlines->l_nblines || lineno < 0) {
    			fatal("invalid line specification in RCS patch");
    		}
    		ep++;
    		nbln = (int)strtol(ep, &ep, 10);
    		/* Restore the last byte of the buffer */
    		lp->l_line[lp->l_len - 1] = tmp;
    		if (nbln < 0)
    			fatal("invalid line number specification in RCS patch");
    
    		/* find the appropriate line */
    		for (;;) {
    			if (dlp == NULL)
    				break;
    			if (dlp->l_lineno == lineno)
    				break;
    			if (dlp->l_lineno > lineno) {
    				dlp = TAILQ_PREV(dlp, tqh, l_list);
    			} else if (dlp->l_lineno < lineno) {
    				if (((ndlp = TAILQ_NEXT(dlp, l_list)) == NULL) ||
    				    ndlp->l_lineno > lineno)
    					break;
    				dlp = ndlp;
    			}
    		}
    		if (dlp == NULL)
    			fatal("can't find referenced line in RCS patch");
    
    		if (op == 'd') {
    			for (i = 0; (i < nbln) && (dlp != NULL); i++) {
    				ndlp = TAILQ_NEXT(dlp, l_list);
    				TAILQ_REMOVE(&(dlines->l_lines), dlp, l_list);
    				if (alines != NULL && dlp->l_line != NULL) {
    					dlp->l_delta = rdp;
    					alines[dlp->l_lineno_orig - 1] =
    						dlp;
    				} else
    					free(dlp);
    				dlp = ndlp;
    				/* last line is gone - reset dlp */
    				if (dlp == NULL) {
    					ndlp = TAILQ_LAST(&(dlines->l_lines),
    					    tqh);
    					dlp = ndlp;
    				}
    			}
    		} else if (op == 'a') {
    			for (i = 0; i < nbln; i++) {
    				ndlp = lp;
    				lp = TAILQ_NEXT(lp, l_list);
    				if (lp == NULL)
    					fatal("truncated RCS patch");
    				TAILQ_REMOVE(&(plines->l_lines), lp, l_list);
    				if (alines != NULL) {
    					if (lp->l_needsfree == 1)
    						free(lp->l_line);
    					lp->l_line = NULL;
    					lp->l_needsfree = 0;
    				}
    				lp->l_delta = rdp;
    				TAILQ_INSERT_AFTER(&(dlines->l_lines), dlp,
    				    lp, l_list);
    				dlp = lp;
    
    				/* we don't want lookup to block on those */
    				lp->l_lineno = lineno;
    
    				lp = ndlp;
    			}
    		} else
    			fatal("unknown RCS patch operation `%c'", op);
    
    		/* last line of the patch, done */
    		if (lp->l_lineno == plines->l_nblines)
    			break;
    	}
    
    	/* once we're done patching, rebuild the line numbers */
    	lineno = 0;
    	TAILQ_FOREACH(lp, &(dlines->l_lines), l_list)
    		lp->l_lineno = lineno++;
    	dlines->l_nblines = lineno - 1;
    
    	return (0);
    }
    
    void
    rcs_delta_stats(struct rcs_delta *rdp, int *ladded, int *lremoved)
    {
    	struct rcs_lines *plines;
    	struct rcs_line *lp;
    	int added, i, nbln, removed;
    	char op, *ep;
    	u_char tmp;
    
    	added = removed = 0;
    
    	plines = cvs_splitlines(rdp->rd_text, rdp->rd_tlen);
    	lp = TAILQ_FIRST(&(plines->l_lines));
    
    	/* skip first bogus line */
    	for (lp = TAILQ_NEXT(lp, l_list); lp != NULL;
    	    lp = TAILQ_NEXT(lp, l_list)) {
    		if (lp->l_len < 2)
    			fatal("line too short, RCS patch seems broken");
    		op = *(lp->l_line);
    		/* NUL-terminate line buffer for strtol() safety. */
    		tmp = lp->l_line[lp->l_len - 1];
    		lp->l_line[lp->l_len - 1] = '\0';
    		(void)strtol((lp->l_line + 1), &ep, 10);
    		ep++;
    		nbln = (int)strtol(ep, &ep, 10);
    		/* Restore the last byte of the buffer */
    		lp->l_line[lp->l_len - 1] = tmp;
    		if (nbln < 0)
    			fatal("invalid line number specification in RCS patch");
    
    		if (op == 'a') {
    			added += nbln;
    			for (i = 0; i < nbln; i++) {
    				lp = TAILQ_NEXT(lp, l_list);
    				if (lp == NULL)
    					fatal("truncated RCS patch");
    			}
    		}
    		else if (op == 'd')
    			removed += nbln;
    		else
    			fatal("unknown RCS patch operation '%c'", op);
    	}
    
    	cvs_freelines(plines);
    
    	*ladded = added;
    	*lremoved = removed;
    }
    
    /*
     * rcs_rev_add()
     *
     * Add a revision to the RCS file <rf>.  The new revision's number can be
     * specified in <rev> (which can also be RCS_HEAD_REV, in which case the
     * new revision will have a number equal to the previous head revision plus
     * one).  The <msg> argument specifies the log message for that revision, and
     * <date> specifies the revision's date (a value of -1 is
     * equivalent to using the current time).
     * If <author> is NULL, set the author for this revision to the current user.
     * Returns 0 on success, or -1 on failure.
     */
    int
    rcs_rev_add(RCSFILE *rf, RCSNUM *rev, const char *msg, time_t date,
        const char *author)
    {
    	time_t now;
    	RCSNUM *root = NULL;
    	struct passwd *pw;
    	struct rcs_branch *brp, *obrp;
    	struct rcs_delta *ordp, *rdp;
    
    	if (rev == RCS_HEAD_REV) {
    		if (rf->rf_flags & RCS_CREATE) {
    			if ((rev = rcsnum_parse(RCS_HEAD_INIT)) == NULL)
    				return (-1);
    			free(rf->rf_head);
    			rf->rf_head = rev;
    		} else if (rf->rf_head == NULL) {
    			return (-1);
    		} else {
    			rev = rcsnum_inc(rf->rf_head);
    		}
    	} else {
    		if ((rdp = rcs_findrev(rf, rev)) != NULL)
    			return (-1);
    	}
    
    	rdp = xcalloc(1, sizeof(*rdp));
    
    	TAILQ_INIT(&(rdp->rd_branches));
    
    	rdp->rd_num = rcsnum_alloc();
    	rcsnum_cpy(rev, rdp->rd_num, 0);
    
    	rdp->rd_next = rcsnum_alloc();
    
    	if (!author && !(author = getlogin())) {
    		if (!(pw = getpwuid(getuid())))
    			fatal("getpwuid failed");
    		author = pw->pw_name;
    	}
    	rdp->rd_author = xstrdup(author);
    	rdp->rd_state = xstrdup(RCS_STATE_EXP);
    	rdp->rd_log = xstrdup(msg);
    
    	if (date != (time_t)(-1))
    		now = date;
    	else
    		time(&now);
    	gmtime_r(&now, &(rdp->rd_date));
    
    	if (RCSNUM_ISBRANCHREV(rev))
    		TAILQ_INSERT_TAIL(&(rf->rf_delta), rdp, rd_list);
    	else
    		TAILQ_INSERT_HEAD(&(rf->rf_delta), rdp, rd_list);
    	rf->rf_ndelta++;
    
    	if (!(rf->rf_flags & RCS_CREATE)) {
    		if (RCSNUM_ISBRANCHREV(rev)) {
    			if (rev->rn_id[rev->rn_len - 1] == 1) {
    				/* a new branch */
    				root = rcsnum_branch_root(rev);
    				brp = xmalloc(sizeof(*brp));
    				brp->rb_num = rcsnum_alloc();
    				rcsnum_cpy(rdp->rd_num, brp->rb_num, 0);
    
    				if ((ordp = rcs_findrev(rf, root)) == NULL)
    					fatal("root node not found");
    
    				TAILQ_FOREACH(obrp, &(ordp->rd_branches),
    				    rb_list) {
    					if (!rcsnum_cmp(obrp->rb_num,
    					    brp->rb_num,
    					    brp->rb_num->rn_len - 1))
    						break;
    				}
    
    				if (obrp == NULL) {
    					TAILQ_INSERT_TAIL(&(ordp->rd_branches),
    					    brp, rb_list);
    				}
    			} else {
    				root = rcsnum_alloc();
    				rcsnum_cpy(rev, root, 0);
    				rcsnum_dec(root);
    				if ((ordp = rcs_findrev(rf, root)) == NULL)
    					fatal("previous revision not found");
    				rcsnum_cpy(rdp->rd_num, ordp->rd_next, 0);
    			}
    		} else {
    			ordp = TAILQ_NEXT(rdp, rd_list);
    			rcsnum_cpy(ordp->rd_num, rdp->rd_next, 0);
    		}
    	}
    
    	free(root);
    
    	/* not synced anymore */
    	rf->rf_flags &= ~RCS_SYNCED;
    
    	return (0);
    }
    
    /*
     * rcs_rev_remove()
     *
     * Remove the revision whose number is <rev> from the RCS file <rf>.
     */
    int
    rcs_rev_remove(RCSFILE *rf, RCSNUM *rev)
    {
    	int fd1, fd2;
    	char *path_tmp1, *path_tmp2;
    	struct rcs_delta *rdp, *prevrdp, *nextrdp;
    	BUF *prevbuf, *newdiff, *newdeltatext;
    
    	if (rev == RCS_HEAD_REV)
    		rev = rf->rf_head;
    
    	if (rev == NULL)
    		return (-1);
    
    	/* do we actually have that revision? */
    	if ((rdp = rcs_findrev(rf, rev)) == NULL)
    		return (-1);
    
    	/*
    	 * This is confusing, the previous delta is next in the TAILQ list.
    	 * the next delta is the previous one in the TAILQ list.
    	 *
    	 * When the HEAD revision got specified, nextrdp will be NULL.
    	 * When the first revision got specified, prevrdp will be NULL.
    	 */
    	prevrdp = (struct rcs_delta *)TAILQ_NEXT(rdp, rd_list);
    	nextrdp = (struct rcs_delta *)TAILQ_PREV(rdp, tqh, rd_list);
    
    	newdeltatext = NULL;
    	prevbuf = NULL;
    	path_tmp1 = path_tmp2 = NULL;
    
    	if (prevrdp != NULL && nextrdp != NULL) {
    		newdiff = buf_alloc(64);
    
    		/* calculate new diff */
    		(void)xasprintf(&path_tmp1, "%s/diff1.XXXXXXXXXX", cvs_tmpdir);
    		fd1 = rcs_rev_write_stmp(rf, nextrdp->rd_num, path_tmp1, 0);
    
    		(void)xasprintf(&path_tmp2, "%s/diff2.XXXXXXXXXX", cvs_tmpdir);
    		fd2 = rcs_rev_write_stmp(rf, prevrdp->rd_num, path_tmp2, 0);
    
    		diff_format = D_RCSDIFF;
    		if (diffreg(path_tmp1, path_tmp2,
    		    fd1, fd2, newdiff, D_FORCEASCII) == D_ERROR)
    			fatal("rcs_diffreg failed");
    
    		close(fd1);
    		close(fd2);
    
    		newdeltatext = newdiff;
    	} else if (nextrdp == NULL && prevrdp != NULL) {
    		newdeltatext = prevbuf;
    	}
    
    	if (newdeltatext != NULL) {
    		if (rcs_deltatext_set(rf, prevrdp->rd_num, newdeltatext) < 0)
    			fatal("error setting new deltatext");
    	}
    
    	TAILQ_REMOVE(&(rf->rf_delta), rdp, rd_list);
    
    	/* update pointers */
    	if (prevrdp != NULL && nextrdp != NULL) {
    		rcsnum_cpy(prevrdp->rd_num, nextrdp->rd_next, 0);
    	} else if (prevrdp != NULL) {
    		if (rcs_head_set(rf, prevrdp->rd_num) < 0)
    			fatal("rcs_head_set failed");
    	} else if (nextrdp != NULL) {
    		free(nextrdp->rd_next);
    		nextrdp->rd_next = rcsnum_alloc();
    	} else {
    		free(rf->rf_head);
    		rf->rf_head = NULL;
    	}
    
    	rf->rf_ndelta--;
    	rf->rf_flags &= ~RCS_SYNCED;
    
    	rcs_freedelta(rdp);
    	free(newdeltatext);
    	free(path_tmp1);
    	free(path_tmp2);
    
    	return (0);
    }
    
    /*
     * rcs_findrev()
     *
     * Find a specific revision's delta entry in the tree of the RCS file <rfp>.
     * The revision number is given in <rev>.
     *
     * Returns a pointer to the delta on success, or NULL on failure.
     */
    struct rcs_delta *
    rcs_findrev(RCSFILE *rfp, RCSNUM *rev)
    {
    	int isbrev;
    	struct rcs_delta *rdp;
    
    	if (rev == NULL)
    		return NULL;
    
    	isbrev = RCSNUM_ISBRANCHREV(rev);
    
    	/*
    	 * We need to do more parsing if the last revision in the linked list
    	 * is greater than the requested revision.
    	 */
    	rdp = TAILQ_LAST(&(rfp->rf_delta), rcs_dlist);
    	if (rdp == NULL ||
    	    (!isbrev && rcsnum_cmp(rdp->rd_num, rev, 0) == -1) ||
    	    ((isbrev && rdp->rd_num->rn_len < 4) ||
    	    (isbrev && rcsnum_differ(rev, rdp->rd_num)))) {
    		if (rcsparse_deltas(rfp, rev))
    			fatal("error parsing deltas");
    	}
    
    	TAILQ_FOREACH(rdp, &(rfp->rf_delta), rd_list) {
    		if (rcsnum_differ(rdp->rd_num, rev))
    			continue;
    		else
    			return (rdp);
    	}
    
    	return (NULL);
    }
    
    /*
     * rcs_kwexp_set()
     *
     * Set the keyword expansion mode to use on the RCS file <file> to <mode>.
     */
    void
    rcs_kwexp_set(RCSFILE *file, int mode)
    {
    	int i;
    	char *tmp, buf[8] = "";
    
    	if (RCS_KWEXP_INVAL(mode))
    		return;
    
    	i = 0;
    	if (mode == RCS_KWEXP_NONE)
    		buf[0] = 'b';
    	else if (mode == RCS_KWEXP_OLD)
    		buf[0] = 'o';
    	else {
    		if (mode & RCS_KWEXP_NAME)
    			buf[i++] = 'k';
    		if (mode & RCS_KWEXP_VAL)
    			buf[i++] = 'v';
    		if (mode & RCS_KWEXP_LKR)
    			buf[i++] = 'l';
    	}
    
    	tmp = xstrdup(buf);
    	free(file->rf_expand);
    	file->rf_expand = tmp;
    	/* not synced anymore */
    	file->rf_flags &= ~RCS_SYNCED;
    }
    
    /*
     * rcs_kwexp_get()
     *
     * Retrieve the keyword expansion mode to be used for the RCS file <file>.
     */
    int
    rcs_kwexp_get(RCSFILE *file)
    {
    	if (file->rf_expand == NULL)
    		return (RCS_KWEXP_DEFAULT);
    
    	return (rcs_kflag_get(file->rf_expand));
    }
    
    /*
     * rcs_kflag_get()
     *
     * Get the keyword expansion mode from a set of character flags given in
     * <flags> and return the appropriate flag mask.  In case of an error, the
     * returned mask will have the RCS_KWEXP_ERR bit set to 1.
     */
    int
    rcs_kflag_get(const char *flags)
    {
    	int fl;
    	size_t len;
    	const char *fp;
    
    	if (flags == NULL || !(len = strlen(flags)))
    		return (RCS_KWEXP_ERR);
    
    	fl = 0;
    	for (fp = flags; *fp != '\0'; fp++) {
    		if (*fp == 'k')
    			fl |= RCS_KWEXP_NAME;
    		else if (*fp == 'v')
    			fl |= RCS_KWEXP_VAL;
    		else if (*fp == 'l')
    			fl |= RCS_KWEXP_LKR;
    		else if (*fp == 'o') {
    			if (len != 1)
    				fl |= RCS_KWEXP_ERR;
    			fl |= RCS_KWEXP_OLD;
    		} else if (*fp == 'b') {
    			if (len != 1)
    				fl |= RCS_KWEXP_ERR;
    			fl |= RCS_KWEXP_NONE;
    		} else	/* unknown letter */
    			fl |= RCS_KWEXP_ERR;
    	}
    
    	return (fl);
    }
    
    /*
     * rcs_freedelta()
     *
     * Free the contents of a delta structure.
     */
    static void
    rcs_freedelta(struct rcs_delta *rdp)
    {
    	struct rcs_branch *rb;
    
    	free(rdp->rd_num);
    	free(rdp->rd_next);
    	free(rdp->rd_author);
    	free(rdp->rd_locker);
    	free(rdp->rd_state);
    	free(rdp->rd_log);
    	free(rdp->rd_text);
    
    	while ((rb = TAILQ_FIRST(&(rdp->rd_branches))) != NULL) {
    		TAILQ_REMOVE(&(rdp->rd_branches), rb, rb_list);
    		free(rb->rb_num);
    		free(rb);
    	}
    
    	free(rdp);
    }
    
    /*
     * rcs_strprint()
     *
     * Output an RCS string <str> of size <slen> to the stream <stream>.  Any
     * '@' characters are escaped.  Otherwise, the string can contain arbitrary
     * binary data.
     */
    static void
    rcs_strprint(const u_char *str, size_t slen, FILE *stream)
    {
    	const u_char *ap, *ep, *sp;
    
    	if (slen == 0)
    		return;
    
    	ep = str + slen - 1;
    
    	for (sp = str; sp <= ep;)  {
    		ap = memchr(sp, '@', ep - sp);
    		if (ap == NULL)
    			ap = ep;
    		(void)fwrite(sp, sizeof(u_char), ap - sp + 1, stream);
    
    		if (*ap == '@')
    			putc('@', stream);
    		sp = ap + 1;
    	}
    }
    
    /*
     * rcs_deltatext_set()
     *
     * Set deltatext for <rev> in RCS file <rfp> to <dtext>
     * Returns -1 on error, 0 on success.
     */
    int
    rcs_deltatext_set(RCSFILE *rfp, RCSNUM *rev, BUF *bp)
    {
    	size_t len;
    	u_char *dtext;
    	struct rcs_delta *rdp;
    
    	/* Write operations require full parsing */
    	if (rcsparse_deltatexts(rfp, NULL))
    		return (-1);
    
    	if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    		return (-1);
    
    	free(rdp->rd_text);
    
    	len = buf_len(bp);
    	dtext = buf_release(bp);
    	bp = NULL;
    
    	if (len != 0) {
    		rdp->rd_text = xmalloc(len);
    		rdp->rd_tlen = len;
    		(void)memcpy(rdp->rd_text, dtext, len);
    	} else {
    		rdp->rd_text = NULL;
    		rdp->rd_tlen = 0;
    	}
    
    	free(dtext);
    	return (0);
    }
    
    /*
     * rcs_rev_setlog()
     *
     * Sets the log message of revision <rev> to <logtext>.
     */
    int
    rcs_rev_setlog(RCSFILE *rfp, RCSNUM *rev, const char *logtext)
    {
    	struct rcs_delta *rdp;
    
    	if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    		return (-1);
    
    	free(rdp->rd_log);
    
    	rdp->rd_log = xstrdup(logtext);
    	rfp->rf_flags &= ~RCS_SYNCED;
    	return (0);
    }
    /*
     * rcs_rev_getdate()
     *
     * Get the date corresponding to a given revision.
     * Returns the date on success, -1 on failure.
     */
    time_t
    rcs_rev_getdate(RCSFILE *rfp, RCSNUM *rev)
    {
    	struct rcs_delta *rdp;
    
    	if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    		return (-1);
    
    	return (timegm(&rdp->rd_date));
    }
    
    /*
     * rcs_state_set()
     *
     * Sets the state of revision <rev> to <state>
     * NOTE: default state is 'Exp'. States may not contain spaces.
     *
     * Returns -1 on failure, 0 on success.
     */
    int
    rcs_state_set(RCSFILE *rfp, RCSNUM *rev, const char *state)
    {
    	struct rcs_delta *rdp;
    
    	if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    		return (-1);
    
    	free(rdp->rd_state);
    
    	rdp->rd_state = xstrdup(state);
    
    	rfp->rf_flags &= ~RCS_SYNCED;
    
    	return (0);
    }
    
    /*
     * rcs_state_check()
     *
     * Check if string <state> is valid.
     *
     * Returns 0 if the string is valid, -1 otherwise.
     */
    int
    rcs_state_check(const char *state)
    {
    	if (strcmp(state, RCS_STATE_DEAD) && strcmp(state, RCS_STATE_EXP))
    		return (-1);
    
    	return (0);
    }
    
    /*
     * rcs_state_get()
     *
     * Get the state for a given revision of a specified RCSFILE.
     *
     * Returns NULL on failure.
     */
    const char *
    rcs_state_get(RCSFILE *rfp, RCSNUM *rev)
    {
    	struct rcs_delta *rdp;
    
    	if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    		return (NULL);
    
    	return (rdp->rd_state);
    }
    
    /* rcs_get_revision() */
    static RCSNUM *
    rcs_get_revision(const char *revstr, RCSFILE *rfp)
    {
    	RCSNUM *rev, *brev, *frev;
    	struct rcs_branch *brp;
    	struct rcs_delta *rdp;
    	size_t i;
    
    	rdp = NULL;
    
    	if (!strcmp(revstr, RCS_HEAD_BRANCH)) {
    		if (rfp->rf_head == NULL)
    			return (NULL);
    
    		frev = rcsnum_alloc();
    		rcsnum_cpy(rfp->rf_head, frev, 0);
    		return (frev);
    	}
    
    	/* Possibly we could be passed a version number */
    	if ((rev = rcsnum_parse(revstr)) != NULL) {
    		/* Do not return if it is not in RCS file */
    		if ((rdp = rcs_findrev(rfp, rev)) != NULL)
    			return (rev);
    	} else {
    		/* More likely we will be passed a symbol */
    		rev = rcs_sym_getrev(rfp, revstr);
    	}
    
    	if (rev == NULL)
    		return (NULL);
    
    	/*
    	 * If it was not a branch, thats ok the symbolic
    	 * name refered to a revision, so return the resolved
    	 * revision for the given name. */
    	if (!RCSNUM_ISBRANCH(rev)) {
    		/* Sanity check: The first two elements of any
    		 * revision (be it on a branch or on trunk) cannot
    		 * be greater than HEAD.
    		 *
    		 * XXX: To avoid comparing to uninitialized memory,
    		 * the minimum of both revision lengths is taken
    		 * instead of just 2.
    		 */
    		if (rfp->rf_head == NULL || rcsnum_cmp(rev, rfp->rf_head,
    		    MINIMUM(rfp->rf_head->rn_len, rev->rn_len)) < 0) {
    			free(rev);
    			return (NULL);
    		}
    		return (rev);
    	}
    
    	brev = rcsnum_alloc();
    	rcsnum_cpy(rev, brev, rev->rn_len - 1);
    
    	if ((rdp = rcs_findrev(rfp, brev)) == NULL)
    		fatal("rcs_get_revision: tag `%s' does not exist", revstr);
    	free(brev);
    
    	TAILQ_FOREACH(brp, &(rdp->rd_branches), rb_list) {
    		for (i = 0; i < rev->rn_len; i++)
    			if (brp->rb_num->rn_id[i] != rev->rn_id[i])
    				break;
    		if (i != rev->rn_len)
    			continue;
    		break;
    	}
    
    	free(rev);
    	frev = rcsnum_alloc();
    	if (brp == NULL) {
    		rcsnum_cpy(rdp->rd_num, frev, 0);
    		return (frev);
    	} else {
    		/* Fetch the delta with the correct branch num */
    		if ((rdp = rcs_findrev(rfp, brp->rb_num)) == NULL)
    			fatal("rcs_get_revision: could not fetch branch "
    			    "delta");
    		rcsnum_cpy(rdp->rd_num, frev, 0);
    		return (frev);
    	}
    }
    
    /*
     * rcs_rev_getlines()
     *
     * Get the entire contents of revision <frev> from the RCSFILE <rfp> and
     * return it as a pointer to a struct rcs_lines.
     */
    struct rcs_lines *
    rcs_rev_getlines(RCSFILE *rfp, RCSNUM *frev, struct rcs_line ***alines)
    {
    	size_t plen;
    	int annotate, done, i, nextroot;
    	RCSNUM *tnum, *bnum;
    	struct rcs_branch *brp;
    	struct rcs_delta *hrdp, *prdp, *rdp, *trdp;
    	u_char *patch;
    	struct rcs_line *line, *nline;
    	struct rcs_lines *dlines, *plines;
    
    	hrdp = prdp = rdp = trdp = NULL;
    
    	if (rfp->rf_head == NULL ||
    	    (hrdp = rcs_findrev(rfp, rfp->rf_head)) == NULL)
    		fatal("rcs_rev_getlines: no HEAD revision");
    
    	tnum = frev;
    	if (rcsparse_deltatexts(rfp, hrdp->rd_num))
    		fatal("rcs_rev_getlines: rcsparse_deltatexts");
    
    	/* revision on branch, get the branch root */
    	nextroot = 2;
    	bnum = rcsnum_alloc();
    	if (RCSNUM_ISBRANCHREV(tnum))
    		rcsnum_cpy(tnum, bnum, nextroot);
    	else
    		rcsnum_cpy(tnum, bnum, tnum->rn_len);
    
    	if (alines != NULL) {
    		/* start with annotate first at requested revision */
    		annotate = ANNOTATE_LATER;
    		*alines = NULL;
    	} else
    		annotate = ANNOTATE_NEVER;
    
    	dlines = cvs_splitlines(hrdp->rd_text, hrdp->rd_tlen);
    
    	done = 0;
    
    	rdp = hrdp;
    	if (!rcsnum_differ(rdp->rd_num, bnum)) {
    		if (annotate == ANNOTATE_LATER) {
    			/* found requested revision for annotate */
    			i = 0;
    			TAILQ_FOREACH(line, &(dlines->l_lines), l_list) {
    				line->l_lineno_orig = line->l_lineno;
    				i++;
    			}
    
    			*alines = xcalloc(i + 1, sizeof(struct rcs_line *));
    			(*alines)[i] = NULL;
    			annotate = ANNOTATE_NOW;
    
    			/* annotate down to 1.1 from where we are */
    			free(bnum);
    			bnum = rcsnum_parse("1.1");
    			if (!rcsnum_differ(rdp->rd_num, bnum)) {
    				goto next;
    			}
    		} else
    			goto next;
    	}
    
    	prdp = hrdp;
    	if ((rdp = rcs_findrev(rfp, hrdp->rd_next)) == NULL)
    		goto done;
    
    again:
    	while (rdp != NULL) {
    		if (rdp->rd_next->rn_len != 0) {
    			trdp = rcs_findrev(rfp, rdp->rd_next);
    			if (trdp == NULL)
    				fatal("failed to grab next revision");
    		}
    
    		if (rdp->rd_tlen == 0) {
    			if (rcsparse_deltatexts(rfp, rdp->rd_num))
    				fatal("rcs_rev_getlines: rcsparse_deltatexts");
    			if (rdp->rd_tlen == 0) {
    				if (!rcsnum_differ(rdp->rd_num, bnum))
    					break;
    				rdp = trdp;
    				continue;
    			}
    		}
    
    		plen = rdp->rd_tlen;
    		patch = rdp->rd_text;
    		plines = cvs_splitlines(patch, plen);
    		if (annotate == ANNOTATE_NOW)
    			rcs_patch_lines(dlines, plines, *alines, prdp);
    		else
    			rcs_patch_lines(dlines, plines, NULL, NULL);
    		cvs_freelines(plines);
    
    		if (!rcsnum_differ(rdp->rd_num, bnum)) {
    			if (annotate != ANNOTATE_LATER)
    				break;
    
    			/* found requested revision for annotate */
    			i = 0;
    			TAILQ_FOREACH(line, &(dlines->l_lines), l_list) {
    				line->l_lineno_orig = line->l_lineno;
    				i++;
    			}
    
    			*alines = xcalloc(i + 1, sizeof(struct rcs_line *));
    			(*alines)[i] = NULL;
    			annotate = ANNOTATE_NOW;
    
    			/* annotate down to 1.1 from where we are */
    			free(bnum);
    			bnum = rcsnum_parse("1.1");
    
    			if (!rcsnum_differ(rdp->rd_num, bnum))
    				break;
    		}
    
    		prdp = rdp;
    		rdp = trdp;
    	}
    
    next:
    	if (rdp == NULL || !rcsnum_differ(rdp->rd_num, frev))
    		done = 1;
    
    	if (RCSNUM_ISBRANCHREV(frev) && done != 1) {
    		nextroot += 2;
    		rcsnum_cpy(frev, bnum, nextroot);
    
    		TAILQ_FOREACH(brp, &(rdp->rd_branches), rb_list) {
    			for (i = 0; i < nextroot - 1; i++)
    				if (brp->rb_num->rn_id[i] != bnum->rn_id[i])
    					break;
    			if (i == nextroot - 1)
    				break;
    		}
    
    		if (brp == NULL) {
    			if (annotate != ANNOTATE_NEVER) {
    				free(*alines);
    				*alines = NULL;
    				cvs_freelines(dlines);
    				free(bnum);
    				return (NULL);
    			}
    			fatal("expected branch not found on branch list");
    		}
    
    		if ((rdp = rcs_findrev(rfp, brp->rb_num)) == NULL)
    			fatal("rcs_rev_getlines: failed to get delta for target rev");
    
    		goto again;
    	}
    done:
    	/* put remaining lines into annotate buffer */
    	if (annotate == ANNOTATE_NOW) {
    		for (line = TAILQ_FIRST(&(dlines->l_lines));
    		    line != NULL; line = nline) {
    			nline = TAILQ_NEXT(line, l_list);
    			TAILQ_REMOVE(&(dlines->l_lines), line, l_list);
    			if (line->l_line == NULL) {
    				free(line);
    				continue;
    			}
    
    			line->l_delta = rdp;
    			(*alines)[line->l_lineno_orig - 1] = line;
    		}
    
    		cvs_freelines(dlines);
    		dlines = NULL;
    	}
    
    	if (bnum != tnum)
    		free(bnum);
    
    	return (dlines);
    }
    
    void
    rcs_annotate_getlines(RCSFILE *rfp, RCSNUM *frev, struct rcs_line ***alines)
    {
    	size_t plen;
    	int i, nextroot;
    	RCSNUM *bnum;
    	struct rcs_branch *brp;
    	struct rcs_delta *rdp, *trdp;
    	u_char *patch;
    	struct rcs_line *line;
    	struct rcs_lines *dlines, *plines;
    
    	rdp = trdp = NULL;
    
    	if (!RCSNUM_ISBRANCHREV(frev))
    		fatal("rcs_annotate_getlines: branch revision expected");
    
    	/* revision on branch, get the branch root */
    	nextroot = 2;
    	bnum = rcsnum_alloc();
    	rcsnum_cpy(frev, bnum, nextroot);
    
    	/*
    	 * Going from HEAD to 1.1 enables the use of an array, which is
    	 * much faster. Unfortunately this is not possible with branch
    	 * revisions, so copy over our alines (array) into dlines (tailq).
    	 */
    	dlines = xcalloc(1, sizeof(*dlines));
    	TAILQ_INIT(&(dlines->l_lines));
    	line = xcalloc(1, sizeof(*line));
    	TAILQ_INSERT_TAIL(&(dlines->l_lines), line, l_list);
    
    	for (i = 0; (*alines)[i] != NULL; i++) {
    		line = (*alines)[i];
    		line->l_lineno = i + 1;
    		TAILQ_INSERT_TAIL(&(dlines->l_lines), line, l_list);
    	}
    
    	rdp = rcs_findrev(rfp, bnum);
    	if (rdp == NULL)
    		fatal("failed to grab branch root revision");
    
    	do {
    		nextroot += 2;
    		rcsnum_cpy(frev, bnum, nextroot);
    
    		TAILQ_FOREACH(brp, &(rdp->rd_branches), rb_list) {
    			for (i = 0; i < nextroot - 1; i++)
    				if (brp->rb_num->rn_id[i] != bnum->rn_id[i])
    					break;
    			if (i == nextroot - 1)
    				break;
    		}
    
    		if (brp == NULL)
    			fatal("expected branch not found on branch list");
    
    		if ((rdp = rcs_findrev(rfp, brp->rb_num)) == NULL)
    			fatal("failed to get delta for target rev");
    
    		for (;;) {
    			if (rdp->rd_next->rn_len != 0) {
    				trdp = rcs_findrev(rfp, rdp->rd_next);
    				if (trdp == NULL)
    					fatal("failed to grab next revision");
    			}
    
    			if (rdp->rd_tlen == 0) {
    				if (rcsparse_deltatexts(rfp, rdp->rd_num))
    					fatal("rcs_annotate_getlines: "
    					    "rcsparse_deltatexts");
    				if (rdp->rd_tlen == 0) {
    					if (!rcsnum_differ(rdp->rd_num, bnum))
    						break;
    					rdp = trdp;
    					continue;
    				}
    			}
    
    			plen = rdp->rd_tlen;
    			patch = rdp->rd_text;
    			plines = cvs_splitlines(patch, plen);
    			rcs_patch_lines(dlines, plines, NULL, rdp);
    			cvs_freelines(plines);
    
    			if (!rcsnum_differ(rdp->rd_num, bnum))
    				break;
    
    			rdp = trdp;
    		}
    	} while (rcsnum_differ(rdp->rd_num, frev));
    
    	if (bnum != frev)
    		free(bnum);
    
    	/*
    	 * All lines have been parsed, now they must be copied over
    	 * into alines (array) again.
    	 */
    	free(*alines);
    
    	i = 0;
    	TAILQ_FOREACH(line, &(dlines->l_lines), l_list) {
    		if (line->l_line != NULL)
    			i++;
    	}
    	*alines = xcalloc(i + 1, sizeof(struct rcs_line *));
    	(*alines)[i] = NULL;
    
    	i = 0;
    	TAILQ_FOREACH(line, &(dlines->l_lines), l_list) {
    		if (line->l_line != NULL)
    			(*alines)[i++] = line;
    	}
    }
    
    /*
     * rcs_rev_getbuf()
     *
     * XXX: This is really really slow and should be avoided if at all possible!
     *
     * Get the entire contents of revision <rev> from the RCSFILE <rfp> and
     * return it as a BUF pointer.
     */
    BUF *
    rcs_rev_getbuf(RCSFILE *rfp, RCSNUM *rev, int mode)
    {
    	int expmode, expand;
    	struct rcs_delta *rdp;
    	struct rcs_lines *lines;
    	struct rcs_line *lp, *nlp;
    	BUF *bp;
    
    	rdp = NULL;
    	expmode = RCS_KWEXP_NONE;
    	expand = 0;
    	lines = rcs_rev_getlines(rfp, rev, NULL);
    	bp = buf_alloc(1024 * 16);
    
    	if (!(mode & RCS_KWEXP_NONE)) {
    		expmode = rcs_kwexp_get(rfp);
    
    		if (!(expmode & RCS_KWEXP_NONE)) {
    			if ((rdp = rcs_findrev(rfp, rev)) == NULL) {
    				char version[RCSNUM_MAXSTR];
    
    				rcsnum_tostr(rev, version, sizeof(version));
    				fatal("could not find desired version %s in %s",
    				    version, rfp->rf_path);
    			}
    
    			expand = 1;
    		}
    	}
    
    	for (lp = TAILQ_FIRST(&lines->l_lines); lp != NULL;) {
    		nlp = TAILQ_NEXT(lp, l_list);
    
    		if (lp->l_line == NULL) {
    			lp = nlp;
    			continue;
    		}
    
    		if (expand)
    			rcs_kwexp_line(rfp->rf_path, rdp, lines, lp, expmode);
    
    		do {
    			buf_append(bp, lp->l_line, lp->l_len);
    		} while ((lp = TAILQ_NEXT(lp, l_list)) != nlp);
    	}
    
    	cvs_freelines(lines);
    
    	return (bp);
    }
    
    /*
     * rcs_rev_write_fd()
     *
     * Write the entire contents of revision <frev> from the rcsfile <rfp> to
     * file descriptor <fd>.
     */
    void
    rcs_rev_write_fd(RCSFILE *rfp, RCSNUM *rev, int _fd, int mode)
    {
    	int fd;
    	FILE *fp;
    	size_t ret;
    	int expmode, expand;
    	struct rcs_delta *rdp;
    	struct rcs_lines *lines;
    	struct rcs_line *lp, *nlp;
    	extern int print_stdout;
    
    	rdp = NULL;
    	expmode = RCS_KWEXP_NONE;
    	expand = 0;
    	lines = rcs_rev_getlines(rfp, rev, NULL);
    
    	if (!(mode & RCS_KWEXP_NONE)) {
    		expmode = rcs_kwexp_get(rfp);
    
    		if (!(expmode & RCS_KWEXP_NONE)) {
    			if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    				fatal("could not fetch revision");
    			expand = 1;
    		}
    	}
    
    	fd = dup(_fd);
    	if (fd == -1)
    		fatal("rcs_rev_write_fd: dup: %s", strerror(errno));
    
    	if ((fp = fdopen(fd, "w")) == NULL)
    		fatal("rcs_rev_write_fd: fdopen: %s", strerror(errno));
    
    	for (lp = TAILQ_FIRST(&lines->l_lines); lp != NULL;) {
    		nlp = TAILQ_NEXT(lp, l_list);
    
    		if (lp->l_line == NULL) {
    			lp = nlp;
    			continue;
    		}
    
    		if (expand)
    			rcs_kwexp_line(rfp->rf_path, rdp, lines, lp, expmode);
    
    		do {
    			/*
    			 * Solely for the checkout and update -p options.
    			 */
    			if (cvs_server_active == 1 &&
    			    (cvs_cmdop == CVS_OP_CHECKOUT ||
    			    cvs_cmdop == CVS_OP_UPDATE) && print_stdout == 1) {
    				ret = fwrite("M ", 1, 2, fp);
    				if (ret != 2)
    					fatal("rcs_rev_write_fd: %s",
    					    strerror(errno));
    			}
    
    			ret = fwrite(lp->l_line, 1, lp->l_len, fp);
    			if (ret != lp->l_len)
    				fatal("rcs_rev_write_fd: %s", strerror(errno));
    		} while ((lp = TAILQ_NEXT(lp, l_list)) != nlp);
    	}
    
    	cvs_freelines(lines);
    	(void)fclose(fp);
    }
    
    /*
     * rcs_rev_write_stmp()
     *
     * Write the contents of the rev <rev> to a temporary file whose path is
     * specified using <template> (see mkstemp(3)). NB. This function will modify
     * <template>, as per mkstemp.
     */
    int
    rcs_rev_write_stmp(RCSFILE *rfp,  RCSNUM *rev, char *template, int mode)
    {
    	int fd;
    
    	if ((fd = mkstemp(template)) == -1)
    		fatal("mkstemp: `%s': %s", template, strerror(errno));
    
    	worklist_add(template, &temp_files);
    	rcs_rev_write_fd(rfp, rev, fd, mode);
    
    	if (lseek(fd, 0, SEEK_SET) == -1)
    		fatal("rcs_rev_write_stmp: lseek: %s", strerror(errno));
    
    	return (fd);
    }
    
    static void
    rcs_kwexp_line(char *rcsfile, struct rcs_delta *rdp, struct rcs_lines *lines,
        struct rcs_line *line, int mode)
    {
    	BUF *tmpbuf;
    	int kwtype;
    	u_int j, found;
    	const u_char *c, *start, *fin, *end;
    	char *kwstr;
    	char expbuf[256], buf[256];
    	size_t clen, kwlen, len, tlen;
    
    	kwtype = 0;
    	kwstr = NULL;
    
    	if (mode & RCS_KWEXP_OLD)
    		return;
    
    	len = line->l_len;
    	if (len == 0)
    		return;
    
    	c = line->l_line;
    	found = 0;
    	/* Final character in buffer. */
    	fin = c + len - 1;
    
    	/*
    	 * Keyword formats:
    	 * $Keyword$
    	 * $Keyword: value$
    	 */
    	for (; c < fin; c++) {
    		if (*c != '$')
    			continue;
    
    		/* remember start of this possible keyword */
    		start = c;
    
    		/* first following character has to be alphanumeric */
    		c++;
    		if (!isalpha(*c)) {
    			c = start;
    			continue;
    		}
    
    		/* Number of characters between c and fin, inclusive. */
    		clen = fin - c + 1;
    
    		/* look for any matching keywords */
    		found = 0;
    		for (j = 0; j < RCS_NKWORDS; j++) {
    			kwlen = strlen(rcs_expkw[j].kw_str);
    			/*
    			 * kwlen must be less than clen since clen
    			 * includes either a terminating `$' or a `:'.
    			 */
    			if (kwlen < clen &&
    			    memcmp(c, rcs_expkw[j].kw_str, kwlen) == 0 &&
    			    (c[kwlen] == '$' || c[kwlen] == ':')) {
    				found = 1;
    				kwstr = rcs_expkw[j].kw_str;
    				kwtype = rcs_expkw[j].kw_type;
    				c += kwlen;
    				break;
    			}
    		}
    
    		if (found == 0 && cvs_tagname != NULL) {
    			kwlen = strlen(cvs_tagname);
    			if (kwlen < clen &&
    			    memcmp(c, cvs_tagname, kwlen) == 0 &&
    			    (c[kwlen] == '$' || c[kwlen] == ':')) {
    				found = 1;
    				kwstr = cvs_tagname;
    				kwtype = RCS_KW_ID;
    				c += kwlen;
    			}
    		}
    
    		/* unknown keyword, continue looking */
    		if (found == 0) {
    			c = start;
    			continue;
    		}
    
    		/*
    		 * if the next character was ':' we need to look for
    		 * an '$' before the end of the line to be sure it is
    		 * in fact a keyword.
    		 */
    		if (*c == ':') {
    			for (; c <= fin; ++c) {
    				if (*c == '$' || *c == '\n')
    					break;
    			}
    
    			if (*c != '$') {
    				c = start;
    				continue;
    			}
    		}
    		end = c + 1;
    
    		/* start constructing the expansion */
    		expbuf[0] = '\0';
    
    		if (mode & RCS_KWEXP_NAME) {
    			if (strlcat(expbuf, "$", sizeof(expbuf)) >=
    			    sizeof(expbuf) || strlcat(expbuf, kwstr,
    			    sizeof(expbuf)) >= sizeof(expbuf))
    				fatal("rcs_kwexp_line: truncated");
    			if ((mode & RCS_KWEXP_VAL) &&
    			    strlcat(expbuf, ": ", sizeof(expbuf)) >=
    			    sizeof(expbuf))
    				fatal("rcs_kwexp_line: truncated");
    		}
    
    		/*
    		 * order matters because of RCS_KW_ID and
    		 * RCS_KW_HEADER here
    		 */
    		if (mode & RCS_KWEXP_VAL) {
    			if (kwtype & RCS_KW_RCSFILE) {
    				if (!(kwtype & RCS_KW_FULLPATH))
    					(void)strlcat(expbuf, basename(rcsfile),
    					    sizeof(expbuf));
    				else
    					(void)strlcat(expbuf, rcsfile,
    					    sizeof(expbuf));
    				if (strlcat(expbuf, " ", sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: truncated");
    			}
    
    			if (kwtype & RCS_KW_REVISION) {
    				rcsnum_tostr(rdp->rd_num, buf, sizeof(buf));
    				if (strlcat(buf, " ", sizeof(buf)) >=
    				    sizeof(buf) || strlcat(expbuf, buf,
    				    sizeof(expbuf)) >= sizeof(buf))
    					fatal("rcs_kwexp_line: truncated");
    			}
    
    			if (kwtype & RCS_KW_DATE) {
    				if (strftime(buf, sizeof(buf),
    				    "%Y/%m/%d %H:%M:%S ",
    				    &rdp->rd_date) == 0)
    					fatal("rcs_kwexp_line: strftime "
    					    "failure");
    				if (strlcat(expbuf, buf, sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    			}
    
    			if (kwtype & RCS_KW_MDOCDATE) {
    				/*
    				 * Do not prepend ' ' for a single
    				 * digit, %e would do so and there is
    				 * no better format for strftime().
    				 */
    				if (strftime(buf, sizeof(buf),
    				    (rdp->rd_date.tm_mday < 10) ?
    				        "%B%e %Y " : "%B %e %Y ",
    				    &rdp->rd_date) == 0)
    					fatal("rcs_kwexp_line: strftime "
    					    "failure");
    				if (strlcat(expbuf, buf, sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    			}
    
    			if (kwtype & RCS_KW_AUTHOR) {
    				if (strlcat(expbuf, rdp->rd_author,
    				    sizeof(expbuf)) >= sizeof(expbuf) ||
    				    strlcat(expbuf, " ", sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    			}
    
    			if (kwtype & RCS_KW_STATE) {
    				if (strlcat(expbuf, rdp->rd_state,
    				    sizeof(expbuf)) >= sizeof(expbuf) ||
    				    strlcat(expbuf, " ", sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    			}
    
    			/* order does not matter anymore below */
    			if (kwtype & RCS_KW_LOG) {
    				char linebuf[256];
    				struct rcs_line *cur, *lp;
    				char *logp, *l_line, *prefix, *q, *sprefix;
    				size_t i;
    
    				/* Log line */
    				if (!(kwtype & RCS_KW_FULLPATH))
    					(void)strlcat(expbuf,
    					    basename(rcsfile), sizeof(expbuf));
    				else
    					(void)strlcat(expbuf, rcsfile,
    					    sizeof(expbuf));
    
    				if (strlcat(expbuf, " ", sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    
    				cur = line;
    
    				/* copy rdp->rd_log for strsep */
    				logp = xstrdup(rdp->rd_log);
    
    				/* copy our prefix for later processing */
    				prefix = xmalloc(start - line->l_line + 1);
    				memcpy(prefix, line->l_line,
    				    start - line->l_line);
    				prefix[start - line->l_line] = '\0';
    
    				/* copy also prefix without trailing blanks. */
    				sprefix = xstrdup(prefix);
    				for (i = strlen(sprefix); i > 0 &&
    				    sprefix[i - 1] == ' '; i--)
    					sprefix[i - 1] = '\0';
    
    				/* new line: revision + date + author */
    				linebuf[0] = '\0';
    				if (strlcat(linebuf, "Revision ",
    				    sizeof(linebuf)) >= sizeof(linebuf))
    					fatal("rcs_kwexp_line: truncated");
    				rcsnum_tostr(rdp->rd_num, buf, sizeof(buf));
    				if (strlcat(linebuf, buf, sizeof(linebuf))
    				    >= sizeof(buf))
    					fatal("rcs_kwexp_line: truncated");
    				if (strftime(buf, sizeof(buf),
    				    "  %Y/%m/%d %H:%M:%S  ",
    				    &rdp->rd_date) == 0)
    					fatal("rcs_kwexp_line: strftime "
    					    "failure");
    				if (strlcat(linebuf, buf, sizeof(linebuf))
    				    >= sizeof(linebuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    				if (strlcat(linebuf, rdp->rd_author,
    				    sizeof(linebuf)) >= sizeof(linebuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    
    				lp = xcalloc(1, sizeof(*lp));
    				xasprintf((char **)&(lp->l_line), "%s%s\n",
    				    prefix, linebuf);
    				lp->l_len = strlen(lp->l_line);
    				TAILQ_INSERT_AFTER(&(lines->l_lines), cur, lp,
    				    l_list);
    				cur = lp;
    
    				/* Log message */
    				q = logp;
    				while ((l_line = strsep(&q, "\n")) != NULL &&
    				    q != NULL) {
    					lp = xcalloc(1, sizeof(*lp));
    
    					if (l_line[0] == '\0') {
    						xasprintf((char **)&(lp->l_line),
    						    "%s\n", sprefix);
    					} else {
    						xasprintf((char **)&(lp->l_line),
    						    "%s%s\n", prefix, l_line);
    					}
    
    					lp->l_len = strlen(lp->l_line);
    					TAILQ_INSERT_AFTER(&(lines->l_lines),
    					    cur, lp, l_list);
    					cur = lp;
    				}
    				free(logp);
    
    				/*
    				 * This is just another hairy mess, but it must
    				 * be done: All characters behind Log will be
    				 * written in a new line next to log messages.
    				 * But that's not enough, we have to strip all
    				 * trailing whitespaces of our prefix.
    				 */
    				lp = xcalloc(1, sizeof(*lp));
    				xasprintf((char **)&lp->l_line, "%s%s",
    				    sprefix, end);
    				lp->l_len = strlen(lp->l_line);
    				TAILQ_INSERT_AFTER(&(lines->l_lines), cur, lp,
    				    l_list);
    				cur = lp;
    
    				end = line->l_line + line->l_len - 1;
    
    				free(prefix);
    				free(sprefix);
    
    			}
    
    			if (kwtype & RCS_KW_SOURCE) {
    				if (strlcat(expbuf, rcsfile, sizeof(expbuf)) >=
    				    sizeof(expbuf) || strlcat(expbuf, " ",
    				    sizeof(expbuf)) >= sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    			}
    
    			if (kwtype & RCS_KW_NAME)
    				if (strlcat(expbuf, " ", sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    
    			if (kwtype & RCS_KW_LOCKER)
    				if (strlcat(expbuf, " ", sizeof(expbuf)) >=
    				    sizeof(expbuf))
    					fatal("rcs_kwexp_line: string "
    					    "truncated");
    		}
    
    		/* end the expansion */
    		if (mode & RCS_KWEXP_NAME)
    			if (strlcat(expbuf, "$",
    			    sizeof(expbuf)) >= sizeof(expbuf))
    				fatal("rcs_kwexp_line: truncated");
    
    		/* Concatenate everything together. */
    		tmpbuf = buf_alloc(len + strlen(expbuf));
    		/* Append everything before keyword. */
    		buf_append(tmpbuf, line->l_line,
    		    start - line->l_line);
    		/* Append keyword. */
    		buf_puts(tmpbuf, expbuf);
    		/* Point c to end of keyword. */
    		tlen = buf_len(tmpbuf) - 1;
    		/* Append everything after keyword. */
    		buf_append(tmpbuf, end,
    		    line->l_line + line->l_len - end);
    		c = buf_get(tmpbuf) + tlen;
    		/* Point fin to end of data. */
    		fin = buf_get(tmpbuf) + buf_len(tmpbuf) - 1;
    		/* Recalculate new length. */
    		len = buf_len(tmpbuf);
    
    		/* tmpbuf is now ready, convert to string */
    		if (line->l_needsfree)
    			free(line->l_line);
    		line->l_len = len;
    		line->l_line = buf_release(tmpbuf);
    		line->l_needsfree = 1;
    	}
    }
    
    /* rcs_translate_tag() */
    RCSNUM *
    rcs_translate_tag(const char *revstr, RCSFILE *rfp)
    {
    	int follow;
    	time_t deltatime;
    	char branch[CVS_REV_BUFSZ];
    	RCSNUM *brev, *frev, *rev;
    	struct rcs_delta *rdp, *trdp;
    	time_t cdate;
    
    	brev = frev = NULL;
    
    	if (revstr == NULL) {
    		if (rfp->rf_branch != NULL) {
    			rcsnum_tostr(rfp->rf_branch, branch, sizeof(branch));
    			revstr = branch;
    		} else {
    			revstr = RCS_HEAD_BRANCH;
    		}
    	}
    
    	if ((rev = rcs_get_revision(revstr, rfp)) == NULL)
    		return (NULL);
    
    	if ((rdp = rcs_findrev(rfp, rev)) == NULL)
    		return (NULL);
    
    	/* let's see if we must follow a branch */
    	if (!strcmp(revstr, RCS_HEAD_BRANCH))
    		follow = 1;
    	else {
    		frev = rcs_sym_getrev(rfp, revstr);
    		if (frev == NULL)
    			frev = rcsnum_parse(revstr);
    
    		brev = rcsnum_alloc();
    		rcsnum_cpy(rev, brev, rev->rn_len - 1);
    
    		if (frev != NULL && RCSNUM_ISBRANCH(frev) &&
    		    !rcsnum_cmp(frev, brev, 0)) {
    			follow = 1;
    		} else
    			follow = 0;
    
    		free(brev);
    	}
    
    	if (cvs_specified_date != -1)
    		cdate = cvs_specified_date;
    	else
    		cdate = cvs_directory_date;
    
    	if (cdate == -1) {
    		free(frev);
    
    		/* XXX */
    		if (rev->rn_len < 4 || !follow) {
    			return (rev);
    		}
    
    		/* Find the latest delta on that branch */
    		free(rev);
    		for (;;) {
    			if (rdp->rd_next->rn_len == 0)
    				break;
    			if ((rdp = rcs_findrev(rfp, rdp->rd_next)) == NULL)
    				fatal("rcs_translate_tag: could not fetch "
    				    "branch delta");
    		}
    
    		rev = rcsnum_alloc();
    		rcsnum_cpy(rdp->rd_num, rev, 0);
    		return (rev);
    	}
    
    	if (frev != NULL) {
    		brev = rcsnum_revtobr(frev);
    		brev->rn_len = rev->rn_len - 1;
    		free(frev);
    	}
    
    	free(rev);
    
    	do {
    		deltatime = timegm(&(rdp->rd_date));
    
    		if (RCSNUM_ISBRANCHREV(rdp->rd_num)) {
    			if (deltatime > cdate) {
    				trdp = TAILQ_PREV(rdp, rcs_dlist, rd_list);
    				if (trdp == NULL)
    					trdp = rdp;
    
    				if (trdp->rd_num->rn_len != rdp->rd_num->rn_len)
    					return (NULL);
    
    				rev = rcsnum_alloc();
    				rcsnum_cpy(trdp->rd_num, rev, 0);
    				return (rev);
    			}
    
    			if (rdp->rd_next->rn_len == 0) {
    				rev = rcsnum_alloc();
    				rcsnum_cpy(rdp->rd_num, rev, 0);
    				return (rev);
    			}
    		} else {
    			if (deltatime < cdate) {
    				rev = rcsnum_alloc();
    				rcsnum_cpy(rdp->rd_num, rev, 0);
    				return (rev);
    			}
    		}
    
    		if (follow && rdp->rd_next->rn_len != 0) {
    			if (brev != NULL && !rcsnum_cmp(brev, rdp->rd_num, 0))
    				break;
    
    			trdp = rcs_findrev(rfp, rdp->rd_next);
    			if (trdp == NULL)
    				fatal("failed to grab next revision");
    			rdp = trdp;
    		} else
    			follow = 0;
    	} while (follow);
    
    	return (NULL);
    }