svr4pkg/pkginstall/cppath.c

	cppath.c revision 5c51f1241dbbdf2656d0e10011981411ed0c9673
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * CDDL HEADER START
66448911ac89c254e89afc52e114402115a497e3David Höppner *
66448911ac89c254e89afc52e114402115a497e3David Höppner * The contents of this file are subject to the terms of the
66448911ac89c254e89afc52e114402115a497e3David Höppner * Common Development and Distribution License (the "License").
66448911ac89c254e89afc52e114402115a497e3David Höppner * You may not use this file except in compliance with the License.
66448911ac89c254e89afc52e114402115a497e3David Höppner *
66448911ac89c254e89afc52e114402115a497e3David Höppner * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
66448911ac89c254e89afc52e114402115a497e3David Höppner * or http://www.opensolaris.org/os/licensing.
66448911ac89c254e89afc52e114402115a497e3David Höppner * See the License for the specific language governing permissions
66448911ac89c254e89afc52e114402115a497e3David Höppner * and limitations under the License.
66448911ac89c254e89afc52e114402115a497e3David Höppner *
66448911ac89c254e89afc52e114402115a497e3David Höppner * When distributing Covered Code, include this CDDL HEADER in each
66448911ac89c254e89afc52e114402115a497e3David Höppner * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
66448911ac89c254e89afc52e114402115a497e3David Höppner * If applicable, add the following below this CDDL HEADER, with the
66448911ac89c254e89afc52e114402115a497e3David Höppner * fields enclosed by brackets "[]" replaced with your own identifying
66448911ac89c254e89afc52e114402115a497e3David Höppner * information: Portions Copyright [yyyy] [name of copyright owner]
66448911ac89c254e89afc52e114402115a497e3David Höppner *
66448911ac89c254e89afc52e114402115a497e3David Höppner * CDDL HEADER END
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
66448911ac89c254e89afc52e114402115a497e3David Höppner * Use is subject to license terms.
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
66448911ac89c254e89afc52e114402115a497e3David Höppner/* All Rights Reserved */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * System includes
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <stdio.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <string.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <stdlib.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <unistd.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <utime.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <locale.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <libintl.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <pkglocs.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <errno.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <fcntl.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <sys/types.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <sys/stat.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * consolidation pkg command library includes
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner#include <pkglib.h>
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * local pkg command library includes
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner#include "libadm.h"
66448911ac89c254e89afc52e114402115a497e3David Höppner#include "libinst.h"
66448911ac89c254e89afc52e114402115a497e3David Höppner#include "install.h"
66448911ac89c254e89afc52e114402115a497e3David Höppner#include "messages.h"
66448911ac89c254e89afc52e114402115a497e3David Höppner#include "pkginstall.h"
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * forward declarations
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppnerstatic int  write_file(char **r_linknam, int a_ctrl, mode_t a_mode,
66448911ac89c254e89afc52e114402115a497e3David Höppner            char *a_file);
66448911ac89c254e89afc52e114402115a497e3David Höppnerstatic int  create_path(int a_ctrl, char *a_file);
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * Name:    cppath
66448911ac89c254e89afc52e114402115a497e3David Höppner * Description: copy a path object (install new file on system)
66448911ac89c254e89afc52e114402115a497e3David Höppner * Arguments:
66448911ac89c254e89afc52e114402115a497e3David Höppner *    - a_cntrl - determine how the destination file mode is set:
66448911ac89c254e89afc52e114402115a497e3David Höppner *  |= MODE_0666 - force mode to 0666
66448911ac89c254e89afc52e114402115a497e3David Höppner *      |= MODE_SET - mode is a_mode (no mask SET?ID bits)
66448911ac89c254e89afc52e114402115a497e3David Höppner *      |= MODE_SRC - mode from source file (mask SET?ID bits)
66448911ac89c254e89afc52e114402115a497e3David Höppner *      |= DIR_DISPLAY - display "%s <implied directory>" if directory created
66448911ac89c254e89afc52e114402115a497e3David Höppner *    - a_srcPath - path to source to copy
66448911ac89c254e89afc52e114402115a497e3David Höppner *    - a_dstPath - path to copy source to
66448911ac89c254e89afc52e114402115a497e3David Höppner *    - a_mode - mode to set a_dstpath to (mode controlled by a_ctrl)
66448911ac89c254e89afc52e114402115a497e3David Höppner * Returns: int
66448911ac89c254e89afc52e114402115a497e3David Höppner *  == 0 - success
66448911ac89c254e89afc52e114402115a497e3David Höppner *  != 0 - failure
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppnerint
66448911ac89c254e89afc52e114402115a497e3David Höppnercppath(int a_ctrl, char *a_srcPath, char *a_dstPath, mode_t a_mode)
66448911ac89c254e89afc52e114402115a497e3David Höppner{
66448911ac89c254e89afc52e114402115a497e3David Höppner    char        *linknam = (char *)NULL;
66448911ac89c254e89afc52e114402115a497e3David Höppner    int     dstFd;
66448911ac89c254e89afc52e114402115a497e3David Höppner    int     len;
66448911ac89c254e89afc52e114402115a497e3David Höppner    int     srcFd;
66448911ac89c254e89afc52e114402115a497e3David Höppner    long        status;
66448911ac89c254e89afc52e114402115a497e3David Höppner    struct stat srcStatbuf;
66448911ac89c254e89afc52e114402115a497e3David Höppner    struct utimbuf  times;
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /* entry debugging info */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    echoDebug(DBG_CPPATH_ENTRY, a_ctrl, a_mode, a_srcPath, a_dstPath);
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /* open source file for reading */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    srcFd = open(a_srcPath, O_RDONLY);
66448911ac89c254e89afc52e114402115a497e3David Höppner    if (srcFd < 0) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        progerr(ERR_OPEN_READ, a_srcPath,
66448911ac89c254e89afc52e114402115a497e3David Höppner                errno, strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner        return (1);
66448911ac89c254e89afc52e114402115a497e3David Höppner    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /* obtain file status of source file */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    if (fstat(srcFd, &srcStatbuf) != 0) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        progerr(ERR_FSTAT, srcFd, a_srcPath, errno, strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner        (void) close(srcFd);
66448911ac89c254e89afc52e114402115a497e3David Höppner        return (1);
66448911ac89c254e89afc52e114402115a497e3David Höppner    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /*
66448911ac89c254e89afc52e114402115a497e3David Höppner     * Determine the permissions mode for the destination:
66448911ac89c254e89afc52e114402115a497e3David Höppner     * - if MODE_SET is specified:
66448911ac89c254e89afc52e114402115a497e3David Höppner     * --> use a_mode (do not mask off any portion)
66448911ac89c254e89afc52e114402115a497e3David Höppner     * --> If a_mode is unknown (? in the pkgmap), then the file gets
66448911ac89c254e89afc52e114402115a497e3David Höppner     * --> installed with the default 0644 mode
66448911ac89c254e89afc52e114402115a497e3David Höppner     * - if MODE_SRC is specified:
66448911ac89c254e89afc52e114402115a497e3David Höppner     * --> use the mode of the source (srcStatbuf.st_mode) but mask off all
66448911ac89c254e89afc52e114402115a497e3David Höppner     * --> non-access mode bits (remove SET?UID bits)
66448911ac89c254e89afc52e114402115a497e3David Höppner     * - otherwise:
66448911ac89c254e89afc52e114402115a497e3David Höppner     * --> use 0666
66448911ac89c254e89afc52e114402115a497e3David Höppner     */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    if (a_ctrl & MODE_SET) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        mode_t  usemode;
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        usemode = (a_mode ^ BADMODE) ? a_mode : 0644;
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (a_mode != usemode && usemode == 0644) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            logerr(WRN_DEF_MODE, a_dstPath);
66448911ac89c254e89afc52e114402115a497e3David Höppner            a_mode = usemode;
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner    } else if (a_ctrl & MODE_SRC) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        a_mode = (srcStatbuf.st_mode & S_IAMB);
66448911ac89c254e89afc52e114402115a497e3David Höppner    } else {
66448911ac89c254e89afc52e114402115a497e3David Höppner        a_mode = 0666;
861bfc8941f2c557f1bcb7a6d7f62f9da98ee4dbTheo Schlossnagle    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /*
66448911ac89c254e89afc52e114402115a497e3David Höppner     * Get fd of newly created destination file or, if this
66448911ac89c254e89afc52e114402115a497e3David Höppner     * is an overwrite,  a temporary file (linknam).
66448911ac89c254e89afc52e114402115a497e3David Höppner     */
66448911ac89c254e89afc52e114402115a497e3David Höppner
e633f2d79475b51f0a4d46972282225abf851733Richard Lowe    dstFd = write_file(&linknam, a_ctrl, a_mode, a_dstPath);
66448911ac89c254e89afc52e114402115a497e3David Höppner    if (dstFd < 0) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        (void) close(srcFd);
66448911ac89c254e89afc52e114402115a497e3David Höppner        return (1);
66448911ac89c254e89afc52e114402115a497e3David Höppner    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /*
66448911ac89c254e89afc52e114402115a497e3David Höppner     * source and target files are open: copy data
66448911ac89c254e89afc52e114402115a497e3David Höppner     */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    status = copyFile(srcFd, dstFd, a_srcPath, a_dstPath, &srcStatbuf, 0);
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    (void) close(srcFd);
66448911ac89c254e89afc52e114402115a497e3David Höppner    (void) close(dstFd);
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    if (status != 0) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        progerr(ERR_INPUT, a_srcPath, errno, strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (linknam) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            (void) remove(linknam);
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner        return (1);
66448911ac89c254e89afc52e114402115a497e3David Höppner    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /*
66448911ac89c254e89afc52e114402115a497e3David Höppner     * If this is an overwrite, rename temp over original
66448911ac89c254e89afc52e114402115a497e3David Höppner     */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    if ((linknam != (char *)NULL) && (rename(linknam, a_dstPath) != 0)) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        FILE    *logfp = (FILE *)NULL;
66448911ac89c254e89afc52e114402115a497e3David Höppner        char    busylog[PATH_MAX];
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* output log message if busy else program error */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (errno == ETXTBSY) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            logerr(MSG_PROCMV, linknam);
66448911ac89c254e89afc52e114402115a497e3David Höppner        } else {
66448911ac89c254e89afc52e114402115a497e3David Höppner            progerr(ERR_OUTPUT_WRITING, a_dstPath, errno,
66448911ac89c254e89afc52e114402115a497e3David Höppner                strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        (void) remove(linknam);
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* open the log file and append log entry */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        len = snprintf(busylog, sizeof (busylog),
66448911ac89c254e89afc52e114402115a497e3David Höppner                "%s/textbusy", get_PKGADM());
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (len > sizeof (busylog)) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            progerr(ERR_CREATE_PATH_2, get_PKGADM(),
66448911ac89c254e89afc52e114402115a497e3David Höppner                "textbusy");
66448911ac89c254e89afc52e114402115a497e3David Höppner        } else {
66448911ac89c254e89afc52e114402115a497e3David Höppner            logfp = fopen(busylog, "a");
66448911ac89c254e89afc52e114402115a497e3David Höppner            if (logfp == NULL) {
66448911ac89c254e89afc52e114402115a497e3David Höppner                progerr(ERR_LOG, busylog, errno,
66448911ac89c254e89afc52e114402115a497e3David Höppner                    strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner            } else {
66448911ac89c254e89afc52e114402115a497e3David Höppner                (void) fprintf(logfp, "%s\n", linknam);
66448911ac89c254e89afc52e114402115a497e3David Höppner                (void) fclose(logfp);
66448911ac89c254e89afc52e114402115a497e3David Höppner            }
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /* set access/modification times for target */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    times.actime = srcStatbuf.st_atime;
66448911ac89c254e89afc52e114402115a497e3David Höppner    times.modtime = srcStatbuf.st_mtime;
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    if (utime(a_dstPath, &times) != 0) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        progerr(ERR_MODTIM, a_dstPath, errno, strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner        return (1);
66448911ac89c254e89afc52e114402115a497e3David Höppner    }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    /* success! */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    return (0);
66448911ac89c254e89afc52e114402115a497e3David Höppner}
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner/*
66448911ac89c254e89afc52e114402115a497e3David Höppner * This function creates all of the directory components of the specified path.
66448911ac89c254e89afc52e114402115a497e3David Höppner */
66448911ac89c254e89afc52e114402115a497e3David Höppnerstatic int
66448911ac89c254e89afc52e114402115a497e3David Höppnercreate_path(int a_ctrl, char *a_file)
66448911ac89c254e89afc52e114402115a497e3David Höppner{
66448911ac89c254e89afc52e114402115a497e3David Höppner    char    *pt;
66448911ac89c254e89afc52e114402115a497e3David Höppner    int found = 0;
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner    for (pt = a_file; *pt; pt++) {
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* continue if not at path separator or at start of path */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        if ((*pt != '/') || (pt == a_file)) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            continue;
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* at '/' - terminate path at current entry */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        *pt = '\0';
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* continue if path element exists */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (access(a_file, F_OK) == 0) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            *pt = '/';
66448911ac89c254e89afc52e114402115a497e3David Höppner            continue;
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* create directory in path */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (mkdir(a_file, 0755)) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            progerr(ERR_MAKE_DIR, a_file, errno, strerror(errno));
66448911ac89c254e89afc52e114402115a497e3David Höppner            *pt = '/';
66448911ac89c254e89afc52e114402115a497e3David Höppner            return (1);
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        /* display 'implied directory created' message */
66448911ac89c254e89afc52e114402115a497e3David Höppner
66448911ac89c254e89afc52e114402115a497e3David Höppner        if (a_ctrl & DIR_DISPLAY) {
66448911ac89c254e89afc52e114402115a497e3David Höppner            echo(MSG_IMPDIR, a_file);
66448911ac89c254e89afc52e114402115a497e3David Höppner        }
66448911ac89c254e89afc52e114402115a497e3David Höppner
        found++;

        *pt = '/';
    }

    return (!found);
}

/*
 * Name:    write_file
 * Description: creates a new destination file if the file does not already
 *      exist; otherwise, creates a temporary file and places a
 *      pointer to the temporary file name in 'r_linknam'.
 * Arguments:   r_linknam - pointer to (char*) where name of temporary file
 *          created is returned
 *      a_ctrl - determine if the destination file name is displayed:
 *           |= DIR_DISPLAY - display "%s <implied directory>"
 *          if directory created
 *      a_mode - permissions mode to set a_file to
 *      a_file - name of destination file to open
 * Returns: int
 *          success - file descriptor of the file it opened.
 *          failure - returns -1
 */

static int
write_file(char **r_linknam, int a_ctrl, mode_t a_mode, char *a_file)
{
    int     len;
    int     fd = -1;
    static char loc_link[PATH_MAX];

    /* entry debugging */

    echoDebug(DBG_WRITEFILE_ENTRY, a_ctrl, a_mode, a_file);

    /* reset pointer to returned 'temporary file name' */

    *r_linknam = (char *)NULL;

    /*
     * If we are overwriting an existing file, arrange to replace
     * it transparently.
     */

    if (access(a_file, F_OK) == 0) {
        /*
         * link the file to be copied to a temporary name in case
         * it is executing or it is being written/used (e.g., a shell
         * script currently being executed
         */

        if (!RELATIVE(a_file)) {
            len = snprintf(loc_link, sizeof (loc_link),
                    "%sXXXXXX", a_file);
            if (len > sizeof (loc_link)) {
                progerr(ERR_CREATE_PATH_2, a_file, "XXXXXX");
            }
        } else {
            logerr(WRN_RELATIVE, a_file);
            len = snprintf(loc_link, sizeof (loc_link),
                    "./%sXXXXXX", a_file);
            if (len > sizeof (loc_link)) {
                progerr(ERR_CREATE_PATH_3, "./", a_file,
                    "XXXXXX");
            }
        }

        /* create and open temporary file */

        fd = mkstemp(loc_link);
        if (fd == -1) {
            progerr(ERR_MKTEMP, loc_link, errno, strerror(errno));
            return (-1);
        }

        /* remember name of temporary file */

        *r_linknam = loc_link;

        /* make sure temporary file has correct mode */

        if (fchmod(fd, a_mode) < 0) {
            progerr(ERR_FCHMOD, loc_link, a_mode, errno,
                strerror(errno));
        }

        return (fd);
    }

    /*
     * We are not overwriting an existing file, create a new one directly.
     */

    fd = open(a_file, O_WRONLY | O_CREAT | O_TRUNC, a_mode);
    if (fd == -1) {
        if (create_path(a_ctrl, a_file) == 0) {
            fd = open(a_file, O_WRONLY | O_CREAT | O_TRUNC, a_mode);
        }
    }

    if (fd == -1) {
        progerr(ERR_OPEN_WRITE, a_file, errno, strerror(errno));
    }

    return (fd);
}