/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1985, 1993
 *      The Regents of the University of California.  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. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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/param.h>
#include <sys/stat.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/dir.h>
#include <protocols/dumprestore.h>

#include <ctype.h>
#include <glob.h>
#include <limits.h>
#include <setjmp.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "restore.h"
#include "extern.h"

/*
 * Things to handle interruptions.
 */
static int runshell;
static jmp_buf reset;
static char *nextarg = NULL;

/*
 * Structure and routines associated with listing directories.
 */
struct afile {
        ino_t   fnum;           /* inode number of file */
        char    *fname;         /* file name */
        short   len;            /* name length */
        char    prefix;         /* prefix character */
        char    postfix;        /* postfix character */
};
struct arglist {
        int     freeglob;       /* glob structure needs to be freed */
        int     argcnt;         /* next globbed argument to return */
        glob_t  glob;           /* globbing information */
        char    *cmd;           /* the current command */
};

static char     *copynext(char *, char *);
static int       fcmp(const void *, const void *);
static void      formatf(struct afile *, int);
static void      getcmd(char *, char *, char *, size_t, struct arglist *);
struct dirent   *glob_readdir(void *);
static int       glob_stat(const char *, struct stat *);
static void      mkentry(char *, struct direct *, struct afile *);
static void      printlist(char *, char *);

/*
 * Read and execute commands from the terminal.
 */
void
runcmdshell(void)
{
        struct entry *np;
        ino_t ino;
        struct arglist arglist;
        char curdir[MAXPATHLEN];
        char name[MAXPATHLEN];
        char cmd[BUFSIZ];

        arglist.freeglob = 0;
        arglist.argcnt = 0;
        arglist.glob.gl_flags = GLOB_ALTDIRFUNC;
        arglist.glob.gl_opendir = rst_opendir;
        arglist.glob.gl_readdir = glob_readdir;
        arglist.glob.gl_closedir = rst_closedir;
        arglist.glob.gl_lstat = glob_stat;
        arglist.glob.gl_stat = glob_stat;
        canon("/", curdir, sizeof(curdir));
loop:
        if (setjmp(reset) != 0) {
                if (arglist.freeglob != 0) {
                        arglist.freeglob = 0;
                        arglist.argcnt = 0;
                        globfree(&arglist.glob);
                }
                nextarg = NULL;
                volno = 0;
        }
        runshell = 1;
        getcmd(curdir, cmd, name, sizeof(name), &arglist);
        switch (cmd[0]) {
        /*
         * Add elements to the extraction list.
         */
        case 'a':
                if (strncmp(cmd, "add", strlen(cmd)) != 0)
                        goto bad;
                ino = dirlookup(name);
                if (ino == 0)
                        break;
                if (mflag)
                        pathcheck(name);
                treescan(name, ino, addfile);
                break;
        /*
         * Change working directory.
         */
        case 'c':
                if (strncmp(cmd, "cd", strlen(cmd)) != 0)
                        goto bad;
                ino = dirlookup(name);
                if (ino == 0)
                        break;
                if (inodetype(ino) == LEAF) {
                        fprintf(stderr, "%s: not a directory\n", name);
                        break;
                }
                (void) strcpy(curdir, name);
                break;
        /*
         * Delete elements from the extraction list.
         */
        case 'd':
                if (strncmp(cmd, "delete", strlen(cmd)) != 0)
                        goto bad;
                np = lookupname(name);
                if (np == NULL || (np->e_flags & NEW) == 0) {
                        fprintf(stderr, "%s: not on extraction list\n", name);
                        break;
                }
                treescan(name, np->e_ino, deletefile);
                break;
        /*
         * Extract the requested list.
         */
        case 'e':
                if (strncmp(cmd, "extract", strlen(cmd)) != 0)
                        goto bad;
                createfiles();
                createlinks();
                setdirmodes(0);
                if (dflag)
                        checkrestore();
                volno = 0;
                break;
        /*
         * List available commands.
         */
        case 'h':
                if (strncmp(cmd, "help", strlen(cmd)) != 0)
                        goto bad;
        case '?':
                fprintf(stderr, "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s",
                        "Available commands are:\n",
                        "\tls [arg] - list directory\n",
                        "\tcd arg - change directory\n",
                        "\tpwd - print current directory\n",
                        "\tadd [arg] - add `arg' to list of",
                        " files to be extracted\n",
                        "\tdelete [arg] - delete `arg' from",
                        " list of files to be extracted\n",
                        "\textract - extract requested files\n",
                        "\tsetmodes - set modes of requested directories\n",
                        "\tquit - immediately exit program\n",
                        "\twhat - list dump header information\n",
                        "\tverbose - toggle verbose flag",
                        " (useful with ``ls'')\n",
                        "\thelp or `?' - print this list\n",
                        "If no `arg' is supplied, the current",
                        " directory is used\n");
                break;
        /*
         * List a directory.
         */
        case 'l':
                if (strncmp(cmd, "ls", strlen(cmd)) != 0)
                        goto bad;
                printlist(name, curdir);
                break;
        /*
         * Print current directory.
         */
        case 'p':
                if (strncmp(cmd, "pwd", strlen(cmd)) != 0)
                        goto bad;
                if (curdir[1] == '\0')
                        fprintf(stderr, "/\n");
                else
                        fprintf(stderr, "%s\n", &curdir[1]);
                break;
        /*
         * Quit.
         */
        case 'q':
                if (strncmp(cmd, "quit", strlen(cmd)) != 0)
                        goto bad;
                return;
        case 'x':
                if (strncmp(cmd, "xit", strlen(cmd)) != 0)
                        goto bad;
                return;
        /*
         * Toggle verbose mode.
         */
        case 'v':
                if (strncmp(cmd, "verbose", strlen(cmd)) != 0)
                        goto bad;
                if (vflag) {
                        fprintf(stderr, "verbose mode off\n");
                        vflag = 0;
                        break;
                }
                fprintf(stderr, "verbose mode on\n");
                vflag++;
                break;
        /*
         * Just restore requested directory modes.
         */
        case 's':
                if (strncmp(cmd, "setmodes", strlen(cmd)) != 0)
                        goto bad;
                setdirmodes(FORCE);
                break;
        /*
         * Print out dump header information.
         */
        case 'w':
                if (strncmp(cmd, "what", strlen(cmd)) != 0)
                        goto bad;
                printdumpinfo();
                break;
        /*
         * Turn on debugging.
         */
        case 'D':
                if (strncmp(cmd, "Debug", strlen(cmd)) != 0)
                        goto bad;
                if (dflag) {
                        fprintf(stderr, "debugging mode off\n");
                        dflag = 0;
                        break;
                }
                fprintf(stderr, "debugging mode on\n");
                dflag++;
                break;
        /*
         * Unknown command.
         */
        default:
        bad:
                fprintf(stderr, "%s: unknown command; type ? for help\n", cmd);
                break;
        }
        goto loop;
}

/*
 * Read and parse an interactive command.
 * The first word on the line is assigned to "cmd". If
 * there are no arguments on the command line, then "curdir"
 * is returned as the argument. If there are arguments
 * on the line they are returned one at a time on each
 * successive call to getcmd. Each argument is first assigned
 * to "name". If it does not start with "/" the pathname in
 * "curdir" is prepended to it. Finally "canon" is called to
 * eliminate any embedded ".." components.
 */
static void
getcmd(char *curdir, char *cmd, char *name, size_t size, struct arglist *ap)
{
        char *cp;
        static char input[BUFSIZ];
        char output[BUFSIZ];
#       define rawname input    /* save space by reusing input buffer */

        /*
         * Check to see if still processing arguments.
         */
        if (ap->argcnt > 0)
                goto retnext;
        if (nextarg != NULL)
                goto getnext;
        /*
         * Read a command line and trim off trailing white space.
         */
        do      {
                fprintf(stderr, "restore > ");
                (void) fflush(stderr);
                if (fgets(input, BUFSIZ, terminal) == NULL) {
                        strcpy(cmd, "quit");
                        return;
                }
        } while (input[0] == '\n');
        for (cp = &input[strlen(input) - 2]; *cp == ' ' || *cp == '\t'; cp--)
                /* trim off trailing white space and newline */;
        *++cp = '\0';
        /*
         * Copy the command into "cmd".
         */
        cp = copynext(input, cmd);
        ap->cmd = cmd;
        /*
         * If no argument, use curdir as the default.
         */
        if (*cp == '\0') {
                (void) strncpy(name, curdir, size);
                name[size - 1] = '\0';
                return;
        }
        nextarg = cp;
        /*
         * Find the next argument.
         */
getnext:
        cp = copynext(nextarg, rawname);
        if (*cp == '\0')
                nextarg = NULL;
        else
                nextarg = cp;
        /*
         * If it is an absolute pathname, canonicalize it and return it.
         */
        if (rawname[0] == '/') {
                canon(rawname, name, size);
        } else {
                /*
                 * For relative pathnames, prepend the current directory to
                 * it then canonicalize and return it.
                 */
                snprintf(output, sizeof(output), "%s/%s", curdir, rawname);
                canon(output, name, size);
        }
        switch (glob(name, GLOB_ALTDIRFUNC, NULL, &ap->glob)) {
        case GLOB_NOSPACE:
                fprintf(stderr, "%s: out of memory\n", ap->cmd);
                break;
        case GLOB_NOMATCH:
                fprintf(stderr, "%s %s: no such file or directory\n", ap->cmd, name);
                break;
        }
        if (ap->glob.gl_pathc == 0)
                return;
        ap->freeglob = 1;
        ap->argcnt = ap->glob.gl_pathc;

retnext:
        strncpy(name, ap->glob.gl_pathv[ap->glob.gl_pathc - ap->argcnt], size);
        name[size - 1] = '\0';
        if (--ap->argcnt == 0) {
                ap->freeglob = 0;
                globfree(&ap->glob);
        }
#       undef rawname
}

/*
 * Strip off the next token of the input.
 */
static char *
copynext(char *input, char *output)
{
        char *cp, *bp;
        char quote;

        for (cp = input; *cp == ' ' || *cp == '\t'; cp++)
                /* skip to argument */;
        bp = output;
        while (*cp != ' ' && *cp != '\t' && *cp != '\0') {
                /*
                 * Handle back slashes.
                 */
                if (*cp == '\\') {
                        if (*++cp == '\0') {
                                fprintf(stderr,
                                        "command lines cannot be continued\n");
                                continue;
                        }
                        *bp++ = *cp++;
                        continue;
                }
                /*
                 * The usual unquoted case.
                 */
                if (*cp != '\'' && *cp != '"') {
                        *bp++ = *cp++;
                        continue;
                }
                /*
                 * Handle single and double quotes.
                 */
                quote = *cp++;
                while (*cp != quote && *cp != '\0')
                        *bp++ = *cp++;
                if (*cp++ == '\0') {
                        fprintf(stderr, "missing %c\n", quote);
                        cp--;
                        continue;
                }
        }
        *bp = '\0';
        return (cp);
}

/*
 * Canonicalize file names to always start with ``./'' and
 * remove any embedded "." and ".." components.
 */
void
canon(char *rawname, char *canonname, size_t len)
{
        char *cp, *np;

        if (strcmp(rawname, ".") == 0 || strncmp(rawname, "./", 2) == 0)
                (void) strcpy(canonname, "");
        else if (rawname[0] == '/')
                (void) strcpy(canonname, ".");
        else
                (void) strcpy(canonname, "./");
        if (strlen(canonname) + strlen(rawname) >= len) {
                fprintf(stderr, "canonname: not enough buffer space\n");
                done(1);
        }
                
        (void) strcat(canonname, rawname);
        /*
         * Eliminate multiple and trailing '/'s
         */
        for (cp = np = canonname; *np != '\0'; cp++) {
                *cp = *np++;
                while (*cp == '/' && *np == '/')
                        np++;
        }
        *cp = '\0';
        if (*--cp == '/')
                *cp = '\0';
        /*
         * Eliminate extraneous "." and ".." from pathnames.
         */
        for (np = canonname; *np != '\0'; ) {
                np++;
                cp = np;
                while (*np != '/' && *np != '\0')
                        np++;
                if (np - cp == 1 && *cp == '.') {
                        cp--;
                        (void) strcpy(cp, np);
                        np = cp;
                }
                if (np - cp == 2 && strncmp(cp, "..", 2) == 0) {
                        cp--;
                        while (cp > &canonname[1] && *--cp != '/')
                                /* find beginning of name */;
                        (void) strcpy(cp, np);
                        np = cp;
                }
        }
}

/*
 * Do an "ls" style listing of a directory
 */
static void
printlist(char *name, char *basename)
{
        struct afile *fp, *list, *listp;
        struct direct *dp;
        struct afile single;
        RST_DIR *dirp;
        int entries, len, namelen;
        char locname[MAXPATHLEN];

        dp = pathsearch(name);
        if (dp == NULL || (!dflag && TSTINO(dp->d_ino, dumpmap) == 0) ||
            (!vflag && dp->d_ino == UFS_WINO))
                return;
        if ((dirp = rst_opendir(name)) == NULL) {
                entries = 1;
                list = &single;
                mkentry(name, dp, list);
                len = strlen(basename) + 1;
                if (strlen(name) - len > single.len) {
                        freename(single.fname);
                        single.fname = savename(&name[len]);
                        single.len = strlen(single.fname);
                }
        } else {
                entries = 0;
                while ((dp = rst_readdir(dirp)))
                        entries++;
                rst_closedir(dirp);
                list = (struct afile *)malloc(entries * sizeof(struct afile));
                if (list == NULL) {
                        fprintf(stderr, "ls: out of memory\n");
                        return;
                }
                if ((dirp = rst_opendir(name)) == NULL)
                        panic("directory reopen failed\n");
                fprintf(stderr, "%s:\n", name);
                entries = 0;
                listp = list;
                (void)strlcpy(locname, name, MAXPATHLEN);
                (void)strlcat(locname, "/", MAXPATHLEN);
                namelen = strlen(locname);
                while ((dp = rst_readdir(dirp))) {
                        if (dp == NULL)
                                break;
                        if (!dflag && TSTINO(dp->d_ino, dumpmap) == 0)
                                continue;
                        if (!vflag && (dp->d_ino == UFS_WINO ||
                             strcmp(dp->d_name, ".") == 0 ||
                             strcmp(dp->d_name, "..") == 0))
                                continue;
                        locname[namelen] = '\0';
                        if (namelen + dp->d_namlen >= MAXPATHLEN) {
                                fprintf(stderr, "%s%s: name exceeds %d char\n",
                                        locname, dp->d_name, MAXPATHLEN);
                        } else {
                                (void)strlcat(locname, dp->d_name, MAXPATHLEN);
                                mkentry(locname, dp, listp++);
                                entries++;
                        }
                }
                rst_closedir(dirp);
                if (entries == 0) {
                        fprintf(stderr, "\n");
                        free(list);
                        return;
                }
                qsort((char *)list, entries, sizeof(struct afile), fcmp);
        }
        formatf(list, entries);
        if (dirp != NULL) {
                for (fp = listp - 1; fp >= list; fp--)
                        freename(fp->fname);
                fprintf(stderr, "\n");
                free(list);
        }
}

/*
 * Read the contents of a directory.
 */
static void
mkentry(char *name, struct direct *dp, struct afile *fp)
{
        char *cp;
        struct entry *np;

        fp->fnum = dp->d_ino;
        fp->fname = savename(dp->d_name);
        for (cp = fp->fname; *cp; cp++)
                if (!vflag && !isprint((unsigned char)*cp))
                        *cp = '?';
        fp->len = cp - fp->fname;
        if (dflag && TSTINO(fp->fnum, dumpmap) == 0)
                fp->prefix = '^';
        else if ((np = lookupname(name)) != NULL && (np->e_flags & NEW))
                fp->prefix = '*';
        else
                fp->prefix = ' ';
        switch(dp->d_type) {

        default:
                fprintf(stderr, "Warning: undefined file type %d\n",
                    dp->d_type);
                /* FALLTHROUGH */
        case DT_REG:
                fp->postfix = ' ';
                break;

        case DT_LNK:
                fp->postfix = '@';
                break;

        case DT_FIFO:
        case DT_SOCK:
                fp->postfix = '=';
                break;

        case DT_CHR:
        case DT_BLK:
                fp->postfix = '#';
                break;

        case DT_WHT:
                fp->postfix = '%';
                break;

        case DT_UNKNOWN:
        case DT_DIR:
                if (inodetype(dp->d_ino) == NODE)
                        fp->postfix = '/';
                else
                        fp->postfix = ' ';
                break;
        }
        return;
}

/*
 * Print out a pretty listing of a directory
 */
static void
formatf(struct afile *list, int nentry)
{
        struct afile *fp, *endlist;
        int width, bigino, haveprefix, havepostfix;
        int i, j, w, precision, columns, lines;

        width = 0;
        haveprefix = 0;
        havepostfix = 0;
        bigino = UFS_ROOTINO;
        endlist = &list[nentry];
        for (fp = &list[0]; fp < endlist; fp++) {
                if (bigino < fp->fnum)
                        bigino = fp->fnum;
                if (width < fp->len)
                        width = fp->len;
                if (fp->prefix != ' ')
                        haveprefix = 1;
                if (fp->postfix != ' ')
                        havepostfix = 1;
        }
        if (haveprefix)
                width++;
        if (havepostfix)
                width++;
        if (vflag) {
                for (precision = 0, i = bigino; i > 0; i /= 10)
                        precision++;
                width += precision + 1;
        }
        width++;
        columns = 81 / width;
        if (columns == 0)
                columns = 1;
        lines = howmany(nentry, columns);
        for (i = 0; i < lines; i++) {
                for (j = 0; j < columns; j++) {
                        fp = &list[j * lines + i];
                        if (vflag) {
                                fprintf(stderr, "%*ju ",
                                    precision, (uintmax_t)fp->fnum);
                                fp->len += precision + 1;
                        }
                        if (haveprefix) {
                                putc(fp->prefix, stderr);
                                fp->len++;
                        }
                        fprintf(stderr, "%s", fp->fname);
                        if (havepostfix) {
                                putc(fp->postfix, stderr);
                                fp->len++;
                        }
                        if (fp + lines >= endlist) {
                                fprintf(stderr, "\n");
                                break;
                        }
                        for (w = fp->len; w < width; w++)
                                putc(' ', stderr);
                }
        }
}

/*
 * Skip over directory entries that are not on the tape
 *
 * First have to get definition of a dirent.
 */
#undef DIRBLKSIZ
#include <dirent.h>
#undef d_ino

struct dirent *
glob_readdir(void *dirp)
{
        struct direct *dp;
        static struct dirent adirent;

        while ((dp = rst_readdir(dirp)) != NULL) {
                if (!vflag && dp->d_ino == UFS_WINO)
                        continue;
                if (dflag || TSTINO(dp->d_ino, dumpmap))
                        break;
        }
        if (dp == NULL)
                return (NULL);
        adirent.d_fileno = dp->d_ino;
        adirent.d_namlen = dp->d_namlen;
        memmove(adirent.d_name, dp->d_name, dp->d_namlen + 1);
        return (&adirent);
}

/*
 * Return st_mode information in response to stat or lstat calls
 */
static int
glob_stat(const char *name, struct stat *stp)
{
        struct direct *dp;

        dp = pathsearch(name);
        if (dp == NULL || (!dflag && TSTINO(dp->d_ino, dumpmap) == 0) ||
            (!vflag && dp->d_ino == UFS_WINO))
                return (-1);
        if (inodetype(dp->d_ino) == NODE)
                stp->st_mode = IFDIR;
        else
                stp->st_mode = IFREG;
        return (0);
}

/*
 * Comparison routine for qsort.
 */
static int
fcmp(const void *f1, const void *f2)
{
        return (strcoll(((struct afile *)f1)->fname,
            ((struct afile *)f2)->fname));
}

/*
 * respond to interrupts
 */
void
onintr(int signo __unused)
{
        if (command == 'i' && runshell)
                longjmp(reset, 1);
        if (reply("restore interrupted, continue") == FAIL)
                done(1);
}