brlcad_path.c

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/*                   B R L C A D _ P A T H . C
 * BRL-CAD
 *
 * Copyright (c) 2004-2006 United States Government as represented by
 * the U.S. Army Research Laboratory.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this file; see the file named COPYING for more
 * information.
 */

/** @addtogroup bu_log */
/*@{*/
/**  @file brlcad_path.c
 * @brief
 *  A support routine to provide the executable code with the path
 *  to where the BRL-CAD programs and libraries are installed.
 *
 *  @author     Christopher Sean Morrison
 *  @author     Michael John Muuss
 *
 *  @par Source
 *      The U. S. Army Research Laboratory                      @n
 *      Aberdeen Proving Ground, Maryland  21005-5068  USA
 */
static const char RCSbrlcad_path[] = "@(#)$Header: /cvsroot/brlcad/brlcad/src/libbu/brlcad_path.c,v 14.29 2006/08/31 23:16:38 lbutler Exp $ (BRL)";

#include "common.h"

#include <stdlib.h>
#include <stdio.h>
#ifdef HAVE_STRING_H
#  include <string.h>
#else
#  include <strings.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#  include <sys/param.h>
#endif

#include "machine.h"
#include "bu.h"


/** 
 *      b u _ i p w d
 * @brief
 * set/return the path to the initial working directory.
 * bu_setprogname() must be called on app startup for the correct pwd to
 * be acquired/set.
 */
static const char *
bu_ipwd()
{
    static const char *pwd = NULL;

    if (pwd) {
        return pwd;
    }

#ifdef HAVE_GETENV
    pwd = getenv("PWD");
#else
    pwd = (char *)NULL;
#endif

    return pwd;
}


/** 
 *              b u _ a r g v 0
 *
 * set the location of argv[0], used by the brlcad-path-finding
 * routines when attempting to locate binaries, libraries, and
 * resources.  This routine may only be called once to set argv0.
 */
static const char *
bu_argv0(const char *path)
{
    static const char *argv0 = NULL;

    /* set our initial pwd if we have not already */
    (void)bu_ipwd();

    if (path) {
        argv0 = path;
    }

    if (argv0) {
        return (argv0);
    }

    /* we were called without a bu_setprogname() so fallback to
     * getprogname() before returning NULL.
     */
#ifdef HAVE_GETPROGNAME
    argv0 = getprogname();
#endif

    return argv0;
}


/** b u _ g e t p r o g n a m e
 *
 * get the name of the running application if they ran
 * bu_setprogname() first or if we know what it's supposed to be
 * anyways.
 */
const char *
bu_getprogname(void) {
    return bu_argv0(NULL);
}



/** b u _ s e t p r o g n a m e
 *
 * Set the name of the running application.  This isn't necessary on
 * modern systems that support getprogname() and call setprogname()
 * before main() for you, but necessary otherwise for portability.
 */
void
bu_setprogname(const char *progname) {
#ifdef HAVE_SETPROGNAME
    setprogname(progname);
#endif
    (void)bu_argv0(progname);
    return;
}


/** b u _ r o o t _ m i s s i n g
 *
 *print out an error/warning message if we cannot find the specified
 * BRLCAD_ROOT (compile-time install path)
 */
static void
bu_root_missing(const char *paths)
{
    bu_log("\
Unable to locate where BRL-CAD %s is installed while searching:\n\
%s\n\
This version of BRL-CAD was compiled to be installed at:\n\
        %s\n\n", BRLCAD_VERSION, paths, BRLCAD_ROOT);

#ifndef _WIN32
    bu_log("\
You may specify where to locate BRL-CAD by setting the BRLCAD_ROOT\n\
environment variable.  For example:\n\
\n\
for csh/tcsh users:\n\
        setenv BRLCAD_ROOT /path/to/brlcad\n\
for sh/bash users:\n\
        BRLCAD_ROOT=/path/to/brlcad ; export BRLCAD_ROOT\n\n");
#endif

    return;
}


/** b u _ d a t a _ m i s s i n g
 *
 * print out an error/warning message if we cannot find the specified
 * BRLCAD_DATA (compile-time install path)
 */
static void
bu_data_missing(const char *paths)
{
    bu_log("\
Unable to locate where BRL-CAD %s data resources are installed\n\
while searching:\n\
%s\n\
This release of BRL-CAD expects data resources to be at:\n\
        %s\n\n", BRLCAD_VERSION, paths, BRLCAD_DATA);

#ifndef _WIN32
    bu_log("\
You may specify where to locate BRL-CAD data resources by setting\n\
the BRLCAD_DATA environment variable.  For example:\n\
\n\
for csh/tcsh users:\n\
        setenv BRLCAD_DATA /path/to/brlcad/data\n\
for sh/bash users:\n\
        BRLCAD_DATA=/path/to/brlcad/data ; export BRLCAD_DATA\n\n");
#endif

    return;
}


/**
 * put a left-hand and right-hand path together and test whether they
 * exist or not.  
 *
 * @return boolean on whether a match was found.
 */
static int
bu_find_path(char result[MAXPATHLEN], const char *lhs, const char *rhs, struct bu_vls *searched, const char *where)
{
    int llen,rlen;
    static const char *currdir=".";

    /* swap right with left if there is no left so logic is simplified
     * later on.
     */
    if (lhs == NULL && rhs != NULL) {
        lhs = rhs;
        rhs = NULL;
    }

    if (lhs == NULL) {
        if (searched && where) {
            bu_vls_strcat(searched, where);
        }
        return 0;
    }

    rlen = llen = 0;
    if (rhs) {
        rlen = strlen(rhs);
    }

    /* be safe */
    if (rlen + 2 > MAXPATHLEN) {
        bu_log("Warning: path is way too long (%d characters > %d)\n", rlen+2, MAXPATHLEN);
        if (searched && where) {
            bu_vls_strcat(searched, where);
        }
        return 0;
    }

    /* an empty left hand implies current directory (plus a slash is appended later) */
    if (lhs[0] == '\0') {
        lhs = currdir;
    }

    /* left-hand path should exist independent of right-hand path */
    if (!bu_file_exists(lhs)) {
        if (searched && where) {
            bu_vls_strcat(searched, where);
        }
        return 0;
    }

    /* start fresh */
    memset(result, 0, MAXPATHLEN);
    strncpy(result, lhs, MAXPATHLEN);

    /* nothing to add, so just return what we have */
    if (!rhs || (rlen == 0)) {
        return 1;
    }

    /* be safe again */
    llen = strlen(result);
    if (llen + rlen + 3 > MAXPATHLEN) {
        bu_log("Warning: path is way too long (%d characters > %d)\n", llen+rlen+3, MAXPATHLEN);
        if (searched && where) {
            bu_vls_strcat(searched, where);
        }
        return 0;
    }

    if ( (*(result+llen-1) != BU_DIR_SEPARATOR) && (rhs[0] != BU_DIR_SEPARATOR) ) {
        /* let the caller give "/usr/brlcad" and "bin" and get "/usr/brlcad/bin" */
        *(result+llen) = BU_DIR_SEPARATOR;
        llen++;
    } else if ( (*(result+llen-1) == BU_DIR_SEPARATOR) && (rhs[0] == BU_DIR_SEPARATOR) ) {
        /* let the caller give "/usr/brlcad/" and "/bin" and get "/usr/brlcad/bin"*/
        rhs++;
        rlen--;
    }

    /* found a match */
    strncpy(result+llen, rhs, MAXPATHLEN - llen);
    if (bu_file_exists(result)) {
        return 1;
    }

    /* close, but no match */
    if (searched && where) {
        bu_vls_strcat(searched, where);
    }
    return 0;
}


/**     B U _ B R L C A D _ R O O T
 *@brief
 * Locate where the BRL-CAD applications and libraries are installed.
 *
 * The BRL-CAD root is searched for in the following order of
 * precedence by testing for the rhs existence if provided or the
 * directory existence otherwise:
 *
 *   BRLCAD_ROOT environment variable if set
 *   BRLCAD_ROOT compile-time path
 *   run-time path identification
 *   /usr/brlcad static path
 *   current directory
 *
 * @return
 * A STATIC buffer is returned.
 * It is the caller's responsibility to call bu_strdup() or make
 * other provisions to save the returned string, before calling again.
 */
char *
bu_brlcad_root(const char *rhs, int fail_quietly)
{
    static char result[MAXPATHLEN] = {0};
    const char *lhs;
    struct bu_vls searched;
    char where[MAXPATHLEN + 64] = {0};

    /* !!!   bu_debug=1; */

    bu_vls_init(&searched);

    if (bu_debug) {
        bu_log("bu_brlcad_root: searching for [%s]\n", rhs);
    }

    /* BRLCAD_ROOT environment variable if set */
    lhs = getenv("BRLCAD_ROOT");
    if (lhs) {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT environment variable [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_ROOT environment variable [%s]\n", result);
            }
            return result;
        }
    } else {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT environment variable\n");
        bu_vls_strcat(&searched, where);
    }

    /* BRLCAD_ROOT compile-time path */
    lhs = BRLCAD_ROOT;
    if (lhs) {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT compile-time path [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_ROOT compile-time path [%s]\n", result);
            }
            return result;
        }
    } else {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT compile-time path [UNKNOWN]\n");
        bu_vls_strcat(&searched, where);
    }

    /* run-time path identification */
    lhs = bu_getprogname();
    if (lhs) {
        char argv0[MAXPATHLEN + 64] = {0};
        int len = strlen(lhs);
        snprintf(argv0, MAXPATHLEN + 64, "%s", lhs);

        /* need to trim off the trailing binary */
        while (len-1 > 0) {
            if (argv0[len-1] == BU_DIR_SEPARATOR) {
                argv0[len] = '.';
                argv0[len+1] = '.';
                argv0[len+2] = '\0';
                break;
            }
            len--;
        }

        snprintf(where, MAXPATHLEN + 64, "\trun-time path identification [%s]\n", argv0);
        if (bu_find_path(result, argv0, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: Run-time path identification [%s]\n", result);
            }
            return result;
        }
    } else {
        snprintf(where, MAXPATHLEN + 64, "\trun-time path identification [UNKNOWN]\n");
        bu_vls_strcat(&searched, where);
    }

    /* /usr/brlcad static path */
    if (strncmp("/usr/brlcad", BRLCAD_ROOT, 12) != 0) {
        if (bu_find_path(result, "/usr/brlcad", rhs, &searched, "\t/usr/brlcad default path\n")) {
            if (bu_debug) {
                bu_log("Found: /usr/brlcad default path [%s]\n", result);
            }
            return result;
        }
    }

    /* current directory */
    if (bu_find_path(result, ".", rhs, &searched, "\tcurrent directory\n")) {
        if (bu_debug) {
            bu_log("Found: current directory [%s]\n", result);
        }
        return result;
    }

    if (!fail_quietly) {
        bu_root_missing(bu_vls_addr(&searched));
        if (rhs) {
            bu_log("Unable to find '%s' within the BRL-CAD software installation.\nThis copy of BRL-CAD may not be properly installed.\n\n", rhs);
        } else {
            bu_log("Unable to find the BRL-CAD software installation.\nThis copy of BRL-CAD may not be properly installed.\n\n");
        }
    }
    return NULL;
}


/**
 *      B U _ B R L C A D _ D A T A
 *
 * @brief
 * Locate where the BRL-CAD data resources are installed.
 *
 * The BRL-CAD data resources are searched for in the following order
 * of precedence by testing for the existence of rhs if provided or
 * the directory existence otherwise:
 *
 *   BRLCAD_DATA environment variable if set
 *   BRLCAD_DATA compile-time path
 *   bu_brlcad_root/share/brlcad/VERSION path
 *   bu_brlcad_root path
 *   current directory
 *
 * A STATIC buffer is returned.
 * It is the caller's responsibility to call bu_strdup() or make
 * other provisions to save the returned string, before calling again.
 */
char *
bu_brlcad_data(const char *rhs, int fail_quietly)
{
    static char result[MAXPATHLEN] = {0};
    const char *lhs;
    struct bu_vls searched;
    char where[MAXPATHLEN + 64] = {0};
    char path[64] = {0};

    /* !!!   bu_debug=1; */

    bu_vls_init(&searched);

    if (bu_debug) {
        bu_log("bu_brlcad_data: looking for [%s]\n", rhs);
    }

    /* BRLCAD_DATA environment variable if set */
    lhs = getenv("BRLCAD_DATA");
    if (lhs) {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_DATA environment variable [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_DATA environment variable [%s]\n", result);
            }
            return result;
        }
    } else {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_DATA environment variable\n");
        bu_vls_strcat(&searched, where);
    }

    /* BRLCAD_DATA compile-time path */
    lhs = BRLCAD_DATA;
    if (lhs) {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_DATA compile-time path [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_DATA compile-time path [%s]\n", result);
            }
            return result;
        }
    } else {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_DATA compile-time path [UNKNOWN]\n");
        bu_vls_strcat(&searched, where);
    }

    /* bu_brlcad_root/share/brlcad/VERSION path */
    snprintf(path, MAXPATHLEN, "share/brlcad/%s", BRLCAD_VERSION);
    lhs = bu_brlcad_root(path, 1);
    if (lhs) {
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT common data path  [%s]\n", path);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_ROOT common data path [%s]\n", result);
            }
            return result;
        }
    }

    /* bu_brlcad_root/share/brlcad path */
    lhs = bu_brlcad_root("share/brlcad", 1);
    if (lhs) {  
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT common data path  [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_ROOT common data path [%s]\n", result);
            }
            return result;
        }
    }

    /* bu_brlcad_root/share path */
    lhs = bu_brlcad_root("share", 1);
    if (lhs) {  
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT common data path  [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_ROOT common data path [%s]\n", result);
            }
            return result;
        }
    }

    /* bu_brlcad_root path */
    lhs = bu_brlcad_root("", 1);
    if (lhs) {  
        snprintf(where, MAXPATHLEN + 64, "\tBRLCAD_ROOT common data path  [%s]\n", lhs);
        if (bu_find_path(result, lhs, rhs, &searched, where)) {
            if (bu_debug) {
                bu_log("Found: BRLCAD_ROOT common data path [%s]\n", result);
            }
            return result;
        }
    }

    /* current directory (running from uninstalled source distribution) */
    if (bu_find_path(result, ".", rhs, &searched, "\tcurrent directory\n")) {
        if (bu_debug) {
            bu_log("Found: current directory [%s]\n", result);
        }
        return result;
    }

    if (!fail_quietly) {
        bu_data_missing(bu_vls_addr(&searched));
        if (rhs) {
            bu_log("Unable to find '%s' within the BRL-CAD software installation.\nThis copy of BRL-CAD may not be properly installed.\n\n", rhs);
        } else {
            bu_log("Unable to find the BRL-CAD software installation.\nThis copy of BRL-CAD may not be properly installed.\n\n");
        }
    }
    return NULL;
}

/**
 *      B U _ B R L C A D _ P A T H
 *
 *  @deprecated
 *  Do not use.  Locate where the BRL-CAD programs and
 *  libraries are located, contatenate on the rest of the string
 *  provided by the caller, and return a pointer to a STATIC buffer
 *  with the full path.  It is the caller's responsibility to call
 *  bu_strdup() or make other provisions to save the returned string,
 *  before calling again.  bu_bomb() if unable to find the base path.
 *
 */
char *
bu_brlcad_path(const char *rhs, int fail_quietly)
{
        bu_log("\
WARNING: bu_brlcad_path is deprecated and will likely disappear in\n\
a future release of BRL-CAD.  Programs and scripts should utilize\n\
bu_brlcad_root and bu_brlcad_data instead.\n\
\n\
Use bu_brlcad_root for the path of applications and libraries.\n\
Use bu_brlcad_data for the path to the data resources.\n\n");

        return bu_brlcad_root(rhs, fail_quietly);
}
/*@}*/
/*
 * Local Variables:
 * mode: C
 * tab-width: 8
 * c-basic-offset: 4
 * indent-tabs-mode: t
 * End:
 * ex: shiftwidth=4 tabstop=8
 */

---