filefuncs.c

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/*
 * filefuncs.c - Builtin functions that provide initial minimal iterface
 *               to the file system.
 *
 * Arnold Robbins, update for 3.1, Mon Nov 23 12:53:39 EST 1998
 */

/*
 * Copyright (C) 2001 the Free Software Foundation, Inc.
 * 
 * This file is part of GAWK, the GNU implementation of the
 * AWK Programming Language.
 * 
 * GAWK is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * GAWK is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
 */

#include "awk.h"

#include <sys/sysmacros.h>

/*  do_chdir --- provide dynamically loaded chdir() builtin for gawk */

static NODE *
do_chdir(tree)
NODE *tree;
{
        NODE *newdir;
        int ret = -1;

        if  (do_lint && tree->param_cnt > 1)
                lintwarn("chdir: called with too many arguments");

        newdir = get_argument(tree, 0);
        if (newdir != NULL) {
                (void) force_string(newdir);
                ret = chdir(newdir->stptr);
                if (ret < 0)
                        update_ERRNO();

                free_temp(newdir);
        } else if (do_lint)
                lintwarn("chdir: called with no arguments");


        /* Set the return value */
        set_value(tmp_number((AWKNUM) ret));

        /* Just to make the interpreter happy */
        return tmp_number((AWKNUM) 0);
}

/* format_mode --- turn a stat mode field into something readable */

static char *
format_mode(fmode)
unsigned long fmode;
{
        static char outbuf[12];
        int i;

        strcpy(outbuf, "----------");
        /* first, get the file type */
        i = 0;
        switch (fmode & S_IFMT) {
#ifdef S_IFSOCK
        case S_IFSOCK:
                outbuf[i] = 's';
                break;
#endif
#ifdef S_IFLNK
        case S_IFLNK:
                outbuf[i] = 'l';
                break;
#endif
        case S_IFREG:
                outbuf[i] = '-';        /* redundant */
                break;
        case S_IFBLK:
                outbuf[i] = 'b';
                break;
        case S_IFDIR:
                outbuf[i] = 'd';
                break;
#ifdef S_IFDOOR /* Solaris weirdness */
        case S_IFDOOR:
                outbuf[i] = 'D';
                break;
#endif /* S_IFDOOR */
        case S_IFCHR:
                outbuf[i] = 'c';
                break;
#ifdef S_IFIFO
        case S_IFIFO:
                outbuf[i] = 'p';
                break;
#endif
        }

        i++;
        if ((fmode & S_IRUSR) != 0)
                outbuf[i] = 'r';
        i++;
        if ((fmode & S_IWUSR) != 0)
                outbuf[i] = 'w';
        i++;
        if ((fmode & S_IXUSR) != 0)
                outbuf[i] = 'x';
        i++;

        if ((fmode & S_IRGRP) != 0)
                outbuf[i] = 'r';
        i++;
        if ((fmode & S_IWGRP) != 0)
                outbuf[i] = 'w';
        i++;
        if ((fmode & S_IXGRP) != 0)
                outbuf[i] = 'x';
        i++;

        if ((fmode & S_IROTH) != 0)
                outbuf[i] = 'r';
        i++;
        if ((fmode & S_IWOTH) != 0)
                outbuf[i] = 'w';
        i++;
        if ((fmode & S_IXOTH) != 0)
                outbuf[i] = 'x';
        i++;

        outbuf[i] = '\0';

        if ((fmode & S_ISUID) != 0) {
                if (outbuf[3] == 'x')
                        outbuf[3] = 's';
                else
                        outbuf[3] = 'S';
        }

        /* setgid without execute == locking */
        if ((fmode & S_ISGID) != 0) {
                if (outbuf[6] == 'x')
                        outbuf[6] = 's';
                else
                        outbuf[6] = 'l';
        }

        if ((fmode & S_ISVTX) != 0) {
                if (outbuf[9] == 'x')
                        outbuf[9] = 't';
                else
                        outbuf[9] = 'T';
        }

        return outbuf;
}

/* do_stat --- provide a stat() function for gawk */

static NODE *
do_stat(tree)
NODE *tree;
{
        NODE *file, *array;
        struct stat sbuf;
        int ret;
        NODE **aptr;
        char *pmode;    /* printable mode */
        char *type = "unknown";

        /* check arg count */
        if (tree->param_cnt != 2)
                fatal(
        "stat: called with incorrect number of arguments (%d), should be 2",
                        tree->param_cnt);

        /* directory is first arg, array to hold results is second */
        file = get_argument(tree, 0);
        array = get_argument(tree, 1);

        array = get_array(array);

        /* empty out the array */
        assoc_clear(array);

        /* lstat the file, if error, set ERRNO and return */
        (void) force_string(file);
        ret = lstat(file->stptr, & sbuf);
        if (ret < 0) {
                update_ERRNO();

                set_value(tmp_number((AWKNUM) ret));

                free_temp(file);
                return tmp_number((AWKNUM) 0);
        }

        /* fill in the array */
        aptr = assoc_lookup(array, tmp_string("name", 4), FALSE);
        *aptr = dupnode(file);

        aptr = assoc_lookup(array, tmp_string("dev", 3), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_dev);

        aptr = assoc_lookup(array, tmp_string("ino", 3), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_ino);

        aptr = assoc_lookup(array, tmp_string("mode", 4), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_mode);

        aptr = assoc_lookup(array, tmp_string("nlink", 5), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_nlink);

        aptr = assoc_lookup(array, tmp_string("uid", 3), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_uid);

        aptr = assoc_lookup(array, tmp_string("gid", 3), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_gid);

        aptr = assoc_lookup(array, tmp_string("size", 4), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_size);

        aptr = assoc_lookup(array, tmp_string("blocks", 6), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_blocks);

        aptr = assoc_lookup(array, tmp_string("atime", 5), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_atime);

        aptr = assoc_lookup(array, tmp_string("mtime", 5), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_mtime);

        aptr = assoc_lookup(array, tmp_string("ctime", 5), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_ctime);

        /* for block and character devices, add rdev, major and minor numbers */
        if (S_ISBLK(sbuf.st_mode) || S_ISCHR(sbuf.st_mode)) {
                aptr = assoc_lookup(array, tmp_string("rdev", 4), FALSE);
                *aptr = make_number((AWKNUM) sbuf.st_rdev);

                aptr = assoc_lookup(array, tmp_string("major", 5), FALSE);
                *aptr = make_number((AWKNUM) major(sbuf.st_rdev));

                aptr = assoc_lookup(array, tmp_string("minor", 5), FALSE);
                *aptr = make_number((AWKNUM) minor(sbuf.st_rdev));
        }

#ifdef HAVE_ST_BLKSIZE
        aptr = assoc_lookup(array, tmp_string("blksize", 7), FALSE);
        *aptr = make_number((AWKNUM) sbuf.st_blksize);
#endif /* HAVE_ST_BLKSIZE */

        aptr = assoc_lookup(array, tmp_string("pmode", 5), FALSE);
        pmode = format_mode(sbuf.st_mode);
        *aptr = make_string(pmode, strlen(pmode));

        /* for symbolic links, add a linkval field */
        if (S_ISLNK(sbuf.st_mode)) {
                char buf[BUFSIZ*2];
                int linksize;

                linksize = readlink(file->stptr, buf, sizeof buf);
                /* should make this smarter */
                if (linksize == sizeof(buf))
                        fatal("size of symbolic link too big");
                buf[linksize] = '\0';

                aptr = assoc_lookup(array, tmp_string("linkval", 7), FALSE);
                *aptr = make_string(buf, linksize);
        }

        /* add a type field */
        switch (sbuf.st_mode & S_IFMT) {
#ifdef S_IFSOCK
        case S_IFSOCK:
                type = "socket";
                break;
#endif
#ifdef S_IFLNK
        case S_IFLNK:
                type = "symlink";
                break;
#endif
        case S_IFREG:
                type = "file";
                break;
        case S_IFBLK:
                type = "blockdev";
                break;
        case S_IFDIR:
                type = "directory";
                break;
#ifdef S_IFDOOR
        case S_IFDOOR:
                type = "door";
                break;
#endif
        case S_IFCHR:
                type = "chardev";
                break;
#ifdef S_IFIFO
        case S_IFIFO:
                type = "fifo";
                break;
#endif
        }

        aptr = assoc_lookup(array, tmp_string("type", 4), FALSE);
        *aptr = make_string(type, strlen(type));

        free_temp(file);

        /* Set the return value */
        set_value(tmp_number((AWKNUM) ret));

        /* Just to make the interpreter happy */
        return tmp_number((AWKNUM) 0);
}

/* dlload --- load new builtins in this library */

NODE *
dlload(tree, dl)
NODE *tree;
void *dl;
{
        make_builtin("chdir", do_chdir, 1);
        make_builtin("stat", do_stat, 2);

        return tmp_number((AWKNUM) 0);
}

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