source: MondoRescue/branches/stable/mindi-busybox/findutils/find.c@ 1770

/* vi: set sw=4 ts=4: */
/*
 * Mini find implementation for busybox
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 *
 * Reworked by David Douthitt <n9ubh@callsign.net> and
 *  Matt Kraai <kraai@alumni.carnegiemellon.edu>.
 *
 * Licensed under the GPL version 2, see the file LICENSE in this tarball.
 */

/* findutils-4.1.20:
 *
 * # find file.txt -exec 'echo {}' '{}  {}' ';'
 * find: echo file.txt: No such file or directory
 * # find file.txt -exec 'echo' '{}  {}' '; '
 * find: missing argument to `-exec'
 * # find file.txt -exec 'echo {}' '{}  {}' ';' junk
 * find: paths must precede expression
 * # find file.txt -exec 'echo {}' '{}  {}' ';' junk ';'
 * find: paths must precede expression
 * # find file.txt -exec 'echo' '{}  {}' ';'
 * file.txt  file.txt
 * (strace: execve("/bin/echo", ["echo", "file.txt  file.txt"], [ 30 vars ]))
 * # find file.txt -exec 'echo' '{}  {}' ';' -print -exec pwd ';'
 * file.txt  file.txt
 * file.txt
 * /tmp
 * # find -name '*.c' -o -name '*.h'
 * [shows files, *.c and *.h intermixed]
 * # find file.txt -name '*f*' -o -name '*t*'
 * file.txt
 * # find file.txt -name '*z*' -o -name '*t*'
 * file.txt
 * # find file.txt -name '*f*' -o -name '*z*'
 * file.txt
 *
 * # find t z -name '*t*' -print -o -name '*z*'
 * t
 * # find t z t z -name '*t*' -o -name '*z*' -print
 * z
 * z
 * # find t z t z '(' -name '*t*' -o -name '*z*' ')' -o -print
 * (no output)
 */

/* Testing script
 * ./busybox find "$@" | tee /tmp/bb_find
 * echo ==================
 * /path/to/gnu/find "$@" | tee /tmp/std_find
 * echo ==================
 * diff -u /tmp/std_find /tmp/bb_find && echo Identical
 */

#include <fnmatch.h>
#include "libbb.h"
#if ENABLE_FEATURE_FIND_REGEX
#include "xregex.h"
#endif

/* This is a NOEXEC applet. Be very careful! */


USE_FEATURE_FIND_XDEV(static dev_t *xdev_dev;)
USE_FEATURE_FIND_XDEV(static int xdev_count;)

typedef int (*action_fp)(const char *fileName, struct stat *statbuf, void *);

typedef struct {
    action_fp f;
#if ENABLE_FEATURE_FIND_NOT
    bool invert;
#endif
} action;
#define ACTS(name, arg...) typedef struct { action a; arg; } action_##name;
#define ACTF(name)         static int func_##name(const char *fileName, struct stat *statbuf, action_##name* ap)
                         ACTS(print)
                         ACTS(name,  const char *pattern;)
USE_FEATURE_FIND_PATH(   ACTS(path,  const char *pattern;))
USE_FEATURE_FIND_REGEX(  ACTS(regex, regex_t compiled_pattern;))
USE_FEATURE_FIND_PRINT0( ACTS(print0))
USE_FEATURE_FIND_TYPE(   ACTS(type,  int type_mask;))
USE_FEATURE_FIND_PERM(   ACTS(perm,  char perm_char; mode_t perm_mask;))
USE_FEATURE_FIND_MTIME(  ACTS(mtime, char mtime_char; unsigned mtime_days;))
USE_FEATURE_FIND_MMIN(   ACTS(mmin,  char mmin_char; unsigned mmin_mins;))
USE_FEATURE_FIND_NEWER(  ACTS(newer, time_t newer_mtime;))
USE_FEATURE_FIND_INUM(   ACTS(inum,  ino_t inode_num;))
USE_FEATURE_FIND_USER(   ACTS(user,  uid_t uid;))
USE_FEATURE_FIND_SIZE(   ACTS(size,  char size_char; off_t size;))
USE_FEATURE_FIND_CONTEXT(ACTS(context, security_context_t context;))
USE_FEATURE_FIND_PAREN(  ACTS(paren, action ***subexpr;))
USE_FEATURE_FIND_PRUNE(  ACTS(prune))
USE_FEATURE_FIND_DELETE( ACTS(delete))
USE_FEATURE_FIND_EXEC(   ACTS(exec,  char **exec_argv; unsigned *subst_count; int exec_argc;))
USE_FEATURE_FIND_GROUP(  ACTS(group, gid_t gid;))

static action ***actions;
static bool need_print = 1;
static int recurse_flags = ACTION_RECURSE;

#if ENABLE_FEATURE_FIND_EXEC
static unsigned count_subst(const char *str)
{
    unsigned count = 0;
    while ((str = strstr(str, "{}")) != NULL) {
        count++;
        str++;
    }
    return count;
}


static char* subst(const char *src, unsigned count, const char* filename)
{
    char *buf, *dst, *end;
    size_t flen = strlen(filename);
    /* we replace each '{}' with filename: growth by strlen-2 */
    buf = dst = xmalloc(strlen(src) + count*(flen-2) + 1);
    while ((end = strstr(src, "{}"))) {
        memcpy(dst, src, end - src);
        dst += end - src;
        src = end + 2;
        memcpy(dst, filename, flen);
        dst += flen;
    }
    strcpy(dst, src);
    return buf;
}
#endif

/* Return values of ACTFs ('action functions') are a bit mask:
 * bit 1=1: prune (use SKIP constant for setting it)
 * bit 0=1: matched successfully (TRUE)
 */

static int exec_actions(action ***appp, const char *fileName, struct stat *statbuf)
{
    int cur_group;
    int cur_action;
    int rc = 0;
    action **app, *ap;

    /* "action group" is a set of actions ANDed together.
     * groups are ORed together.
     * We simply evaluate each group until we find one in which all actions
     * succeed. */

    /* -prune is special: if it is encountered, then we won't
     * descend into current directory. It doesn't matter whether
     * action group (in which -prune sits) will succeed or not:
     * find * -prune -name 'f*' -o -name 'm*' -- prunes every dir
     * find * -name 'f*' -o -prune -name 'm*' -- prunes all dirs
     *     not starting with 'f' */

    /* We invert TRUE bit (bit 0). Now 1 there means 'failure'.
     * and bitwise OR in "rc |= TRUE ^ ap->f()" will:
     * (1) make SKIP (-prune) bit stick; and (2) detect 'failure'.
     * On return, bit is restored.  */

    cur_group = -1;
    while ((app = appp[++cur_group])) {
        rc &= ~TRUE; /* 'success' so far, clear TRUE bit */
        cur_action = -1;
        while (1) {
            ap = app[++cur_action];
            if (!ap) /* all actions in group were successful */
                return rc ^ TRUE; /* restore TRUE bit */
            rc |= TRUE ^ ap->f(fileName, statbuf, ap);
#if ENABLE_FEATURE_FIND_NOT
            if (ap->invert) rc ^= TRUE;
#endif
            if (rc & TRUE) /* current group failed, try next */
                break;
        }
    }
    return rc ^ TRUE; /* restore TRUE bit */
}


ACTF(name)
{
    const char *tmp = bb_basename(fileName);
    if (tmp != fileName && !*tmp) { /* "foo/bar/". Oh no... go back to 'b' */
        tmp--;
        while (tmp != fileName && *--tmp != '/')
            continue;
        if (*tmp == '/')
            tmp++;
    }
    return fnmatch(ap->pattern, tmp, FNM_PERIOD) == 0;
}
#if ENABLE_FEATURE_FIND_PATH
ACTF(path)
{
    return fnmatch(ap->pattern, fileName, 0) == 0;
}
#endif
#if ENABLE_FEATURE_FIND_REGEX
ACTF(regex)
{
    regmatch_t match;
    if (regexec(&ap->compiled_pattern, fileName, 1, &match, 0 /*eflags*/))
        return 0; /* no match */
    if (match.rm_so)
        return 0; /* match doesn't start at pos 0 */
    if (fileName[match.rm_eo])
        return 0; /* match doesn't end exactly at end of pathname */
    return 1;
}
#endif
#if ENABLE_FEATURE_FIND_TYPE
ACTF(type)
{
    return ((statbuf->st_mode & S_IFMT) == ap->type_mask);
}
#endif
#if ENABLE_FEATURE_FIND_PERM
ACTF(perm)
{
    /* -perm +mode: at least one of perm_mask bits are set */
    if (ap->perm_char == '+')
        return (statbuf->st_mode & ap->perm_mask) != 0;
    /* -perm -mode: all of perm_mask are set */
    if (ap->perm_char == '-')
        return (statbuf->st_mode & ap->perm_mask) == ap->perm_mask;
    /* -perm mode: file mode must match perm_mask */
    return (statbuf->st_mode & 07777) == ap->perm_mask;
}
#endif
#if ENABLE_FEATURE_FIND_MTIME
ACTF(mtime)
{
    time_t file_age = time(NULL) - statbuf->st_mtime;
    time_t mtime_secs = ap->mtime_days * 24*60*60;
    if (ap->mtime_char == '+')
        return file_age >= mtime_secs + 24*60*60;
    if (ap->mtime_char == '-')
        return file_age < mtime_secs;
    /* just numeric mtime */
    return file_age >= mtime_secs && file_age < (mtime_secs + 24*60*60);
}
#endif
#if ENABLE_FEATURE_FIND_MMIN
ACTF(mmin)
{
    time_t file_age = time(NULL) - statbuf->st_mtime;
    time_t mmin_secs = ap->mmin_mins * 60;
    if (ap->mmin_char == '+')
        return file_age >= mmin_secs + 60;
    if (ap->mmin_char == '-')
        return file_age < mmin_secs;
    /* just numeric mmin */
    return file_age >= mmin_secs && file_age < (mmin_secs + 60);
}
#endif
#if ENABLE_FEATURE_FIND_NEWER
ACTF(newer)
{
    return (ap->newer_mtime < statbuf->st_mtime);
}
#endif
#if ENABLE_FEATURE_FIND_INUM
ACTF(inum)
{
    return (statbuf->st_ino == ap->inode_num);
}
#endif
#if ENABLE_FEATURE_FIND_EXEC
ACTF(exec)
{
    int i, rc;
    char *argv[ap->exec_argc + 1];
    for (i = 0; i < ap->exec_argc; i++)
        argv[i] = subst(ap->exec_argv[i], ap->subst_count[i], fileName);
    argv[i] = NULL; /* terminate the list */

    rc = spawn_and_wait(argv);
    if (rc < 0)
        bb_perror_msg("%s", argv[0]);

    i = 0;
    while (argv[i])
        free(argv[i++]);
    return rc == 0; /* return 1 if exitcode 0 */
}
#endif
#if ENABLE_FEATURE_FIND_USER
ACTF(user)
{
    return (statbuf->st_uid == ap->uid);
}
#endif
#if ENABLE_FEATURE_FIND_GROUP
ACTF(group)
{
    return (statbuf->st_gid == ap->gid);
}
#endif
#if ENABLE_FEATURE_FIND_PRINT0
ACTF(print0)
{
    printf("%s%c", fileName, '\0');
    return TRUE;
}
#endif
ACTF(print)
{
    puts(fileName);
    return TRUE;
}
#if ENABLE_FEATURE_FIND_PAREN
ACTF(paren)
{
    return exec_actions(ap->subexpr, fileName, statbuf);
}
#endif
#if ENABLE_FEATURE_FIND_SIZE
ACTF(size)
{
    if (ap->size_char == '+')
        return statbuf->st_size > ap->size;
    if (ap->size_char == '-')
        return statbuf->st_size < ap->size;
    return statbuf->st_size == ap->size;
}
#endif
#if ENABLE_FEATURE_FIND_PRUNE
/*
 * -prune: if -depth is not given, return true and do not descend
 * current dir; if -depth is given, return false with no effect.
 * Example:
 * find dir -name 'asm-*' -prune -o -name '*.[chS]' -print
 */
ACTF(prune)
{
    return SKIP + TRUE;
}
#endif
#if ENABLE_FEATURE_FIND_DELETE
ACTF(delete)
{
    int rc;
    if (S_ISDIR(statbuf->st_mode)) {
        rc = rmdir(fileName);
    } else {
        rc = unlink(fileName);
    }
    if (rc < 0)
        bb_perror_msg("%s", fileName);
    return TRUE;
}
#endif
#if ENABLE_FEATURE_FIND_CONTEXT
ACTF(context)
{
    security_context_t con;
    int rc;

    if (recurse_flags & ACTION_FOLLOWLINKS) {
        rc = getfilecon(fileName, &con);
    } else {
        rc = lgetfilecon(fileName, &con);
    }
    if (rc < 0)
        return FALSE;
    rc = strcmp(ap->context, con);
    freecon(con);
    return rc == 0;
}
#endif


static int fileAction(const char *fileName, struct stat *statbuf, void *userData, int depth)
{
    int i;
#if ENABLE_FEATURE_FIND_MAXDEPTH
    int maxdepth = (int)(ptrdiff_t)userData;

    if (depth > maxdepth) return SKIP;
#endif

#if ENABLE_FEATURE_FIND_XDEV
    if (S_ISDIR(statbuf->st_mode) && xdev_count) {
        for (i = 0; i < xdev_count; i++) {
            if (xdev_dev[i] == statbuf->st_dev)
                break;
        }
        if (i == xdev_count)
            return SKIP;
    }
#endif
    i = exec_actions(actions, fileName, statbuf);
    /* Had no explicit -print[0] or -exec? then print */
    if ((i & TRUE) && need_print)
        puts(fileName);
    /* Cannot return 0: our caller, recursive_action(),
     * will perror() and skip dirs (if called on dir) */
    return (i & SKIP) ? SKIP : TRUE;
}


#if ENABLE_FEATURE_FIND_TYPE
static int find_type(const char *type)
{
    int mask = 0;

    if (*type == 'b')
        mask = S_IFBLK;
    else if (*type == 'c')
        mask = S_IFCHR;
    else if (*type == 'd')
        mask = S_IFDIR;
    else if (*type == 'p')
        mask = S_IFIFO;
    else if (*type == 'f')
        mask = S_IFREG;
    else if (*type == 'l')
        mask = S_IFLNK;
    else if (*type == 's')
        mask = S_IFSOCK;

    if (mask == 0 || *(type + 1) != '\0')
        bb_error_msg_and_die(bb_msg_invalid_arg, type, "-type");

    return mask;
}
#endif

#if ENABLE_FEATURE_FIND_PERM \
 || ENABLE_FEATURE_FIND_MTIME || ENABLE_FEATURE_FIND_MMIN \
 || ENABLE_FEATURE_FIND_SIZE
static const char* plus_minus_num(const char* str)
{
    if (*str == '-' || *str == '+')
        str++;
    return str;
}
#endif

static action*** parse_params(char **argv)
{
    enum {
                             PARM_a         ,
                             PARM_o         ,
    USE_FEATURE_FIND_NOT(    PARM_char_not  ,)
#if ENABLE_DESKTOP
                             PARM_and       ,
                             PARM_or        ,
    USE_FEATURE_FIND_NOT(    PARM_not       ,)
#endif
                             PARM_print     ,
    USE_FEATURE_FIND_PRINT0( PARM_print0    ,)
    USE_FEATURE_FIND_DEPTH(  PARM_depth     ,)
    USE_FEATURE_FIND_PRUNE(  PARM_prune     ,)
    USE_FEATURE_FIND_DELETE( PARM_delete    ,)
    USE_FEATURE_FIND_EXEC(   PARM_exec      ,)
    USE_FEATURE_FIND_PAREN(  PARM_char_brace,)
    /* All options starting from here require argument */
                             PARM_name      ,
    USE_FEATURE_FIND_PATH(   PARM_path      ,)
    USE_FEATURE_FIND_REGEX(  PARM_regex     ,)
    USE_FEATURE_FIND_TYPE(   PARM_type      ,)
    USE_FEATURE_FIND_PERM(   PARM_perm      ,)
    USE_FEATURE_FIND_MTIME(  PARM_mtime     ,)
    USE_FEATURE_FIND_MMIN(   PARM_mmin      ,)
    USE_FEATURE_FIND_NEWER(  PARM_newer     ,)
    USE_FEATURE_FIND_INUM(   PARM_inum      ,)
    USE_FEATURE_FIND_USER(   PARM_user      ,)
    USE_FEATURE_FIND_GROUP(  PARM_group     ,)
    USE_FEATURE_FIND_SIZE(   PARM_size      ,)
    USE_FEATURE_FIND_CONTEXT(PARM_context   ,)
    };

    static const char params[] ALIGN1 =
                             "-a\0"
                             "-o\0"
    USE_FEATURE_FIND_NOT(    "!\0"       )
#if ENABLE_DESKTOP
                             "-and\0"
                             "-or\0"
    USE_FEATURE_FIND_NOT(    "-not\0"    )
#endif
                             "-print\0"
    USE_FEATURE_FIND_PRINT0( "-print0\0" )
    USE_FEATURE_FIND_DEPTH(  "-depth\0"  )
    USE_FEATURE_FIND_PRUNE(  "-prune\0"  )
    USE_FEATURE_FIND_DELETE( "-delete\0" )
    USE_FEATURE_FIND_EXEC(   "-exec\0"   )
    USE_FEATURE_FIND_PAREN(  "(\0"       )
    /* All options starting from here require argument */
                             "-name\0"
    USE_FEATURE_FIND_PATH(   "-path\0"   )
    USE_FEATURE_FIND_REGEX(  "-regex\0"  )
    USE_FEATURE_FIND_TYPE(   "-type\0"   )
    USE_FEATURE_FIND_PERM(   "-perm\0"   )
    USE_FEATURE_FIND_MTIME(  "-mtime\0"  )
    USE_FEATURE_FIND_MMIN(   "-mmin\0"   )
    USE_FEATURE_FIND_NEWER(  "-newer\0"  )
    USE_FEATURE_FIND_INUM(   "-inum\0"   )
    USE_FEATURE_FIND_USER(   "-user\0"   )
    USE_FEATURE_FIND_GROUP(  "-group\0"  )
    USE_FEATURE_FIND_SIZE(   "-size\0"   )
    USE_FEATURE_FIND_CONTEXT("-context\0")
                             ;

    action*** appp;
    unsigned cur_group = 0;
    unsigned cur_action = 0;
    USE_FEATURE_FIND_NOT( bool invert_flag = 0; )

    /* 'static' doesn't work here! (gcc 4.1.2) */
    action* alloc_action(int sizeof_struct, action_fp f)
    {
        action *ap;
        appp[cur_group] = xrealloc(appp[cur_group], (cur_action+2) * sizeof(*appp));
        appp[cur_group][cur_action++] = ap = xmalloc(sizeof_struct);
        appp[cur_group][cur_action] = NULL;
        ap->f = f;
        USE_FEATURE_FIND_NOT( ap->invert = invert_flag; )
        USE_FEATURE_FIND_NOT( invert_flag = 0; )
        return ap;
    }

#define ALLOC_ACTION(name) (action_##name*)alloc_action(sizeof(action_##name), (action_fp) func_##name)

    appp = xzalloc(2 * sizeof(appp[0])); /* appp[0],[1] == NULL */

/* Actions have side effects and return a true or false value
 * We implement: -print, -print0, -exec
 *
 * The rest are tests.
 *
 * Tests and actions are grouped by operators
 * ( expr )              Force precedence
 * ! expr                True if expr is false
 * -not expr             Same as ! expr
 * expr1 [-a[nd]] expr2  And; expr2 is not evaluated if expr1 is false
 * expr1 -o[r] expr2     Or; expr2 is not evaluated if expr1 is true
 * expr1 , expr2         List; both expr1 and expr2 are always evaluated
 * We implement: (), -a, -o
 */
    while (*argv) {
        const char *arg = argv[0];
        int parm = index_in_strings(params, arg);
        const char *arg1 = argv[1];

        if (parm >= PARM_name) {
            /* All options starting from -name require argument */
            if (!arg1)
                bb_error_msg_and_die(bb_msg_requires_arg, arg);
            argv++;
        }

        /* We can use big switch() here, but on i386
         * it doesn't give smaller code. Other arches? */

    /* --- Operators --- */
        if (parm == PARM_a USE_DESKTOP(|| parm == PARM_and)) {
            /* no further special handling required */
        }
        else if (parm == PARM_o USE_DESKTOP(|| parm == PARM_or)) {
            /* start new OR group */
            cur_group++;
            appp = xrealloc(appp, (cur_group+2) * sizeof(*appp));
            /*appp[cur_group] = NULL; - already NULL */
            appp[cur_group+1] = NULL;
            cur_action = 0;
        }
#if ENABLE_FEATURE_FIND_NOT
        else if (parm == PARM_char_not USE_DESKTOP(|| parm == PARM_not)) {
            /* also handles "find ! ! -name 'foo*'" */
            invert_flag ^= 1;
        }
#endif

    /* --- Tests and actions --- */
        else if (parm == PARM_print) {
            need_print = 0;
            /* GNU find ignores '!' here: "find ! -print" */
            USE_FEATURE_FIND_NOT( invert_flag = 0; )
            (void) ALLOC_ACTION(print);
        }
#if ENABLE_FEATURE_FIND_PRINT0
        else if (parm == PARM_print0) {
            need_print = 0;
            USE_FEATURE_FIND_NOT( invert_flag = 0; )
            (void) ALLOC_ACTION(print0);
        }
#endif
#if ENABLE_FEATURE_FIND_DEPTH
        else if (parm == PARM_depth) {
            recurse_flags |= ACTION_DEPTHFIRST;
        }
#endif
#if ENABLE_FEATURE_FIND_PRUNE
        else if (parm == PARM_prune) {
            USE_FEATURE_FIND_NOT( invert_flag = 0; )
            (void) ALLOC_ACTION(prune);
        }
#endif
#if ENABLE_FEATURE_FIND_DELETE
        else if (parm == PARM_delete) {
            need_print = 0;
            recurse_flags |= ACTION_DEPTHFIRST;
            (void) ALLOC_ACTION(delete);
        }
#endif
#if ENABLE_FEATURE_FIND_EXEC
        else if (parm == PARM_exec) {
            int i;
            action_exec *ap;
            need_print = 0;
            USE_FEATURE_FIND_NOT( invert_flag = 0; )
            ap = ALLOC_ACTION(exec);
            ap->exec_argv = ++argv; /* first arg after -exec */
            ap->exec_argc = 0;
            while (1) {
                if (!*argv) /* did not see ';' until end */
                    bb_error_msg_and_die("-exec CMD must end by ';'");
                if (LONE_CHAR(argv[0], ';'))
                    break;
                argv++;
                ap->exec_argc++;
            }
            if (ap->exec_argc == 0)
                bb_error_msg_and_die(bb_msg_requires_arg, arg);
            ap->subst_count = xmalloc(ap->exec_argc * sizeof(int));
            i = ap->exec_argc;
            while (i--)
                ap->subst_count[i] = count_subst(ap->exec_argv[i]);
        }
#endif
#if ENABLE_FEATURE_FIND_PAREN
        else if (parm == PARM_char_brace) {
            action_paren *ap;
            char **endarg;
            unsigned nested = 1;

            endarg = argv;
            while (1) {
                if (!*++endarg)
                    bb_error_msg_and_die("unpaired '('");
                if (LONE_CHAR(*endarg, '('))
                    nested++;
                else if (LONE_CHAR(*endarg, ')') && !--nested) {
                    *endarg = NULL;
                    break;
                }
            }
            ap = ALLOC_ACTION(paren);
            ap->subexpr = parse_params(argv + 1);
            *endarg = (char*) ")"; /* restore NULLed parameter */
            argv = endarg;
        }
#endif
        else if (parm == PARM_name) {
            action_name *ap;
            ap = ALLOC_ACTION(name);
            ap->pattern = arg1;
        }
#if ENABLE_FEATURE_FIND_PATH
        else if (parm == PARM_path) {
            action_path *ap;
            ap = ALLOC_ACTION(path);
            ap->pattern = arg1;
        }
#endif
#if ENABLE_FEATURE_FIND_REGEX
        else if (parm == PARM_regex) {
            action_regex *ap;
            ap = ALLOC_ACTION(regex);
            xregcomp(&ap->compiled_pattern, arg1, 0 /*cflags*/);
        }
#endif
#if ENABLE_FEATURE_FIND_TYPE
        else if (parm == PARM_type) {
            action_type *ap;
            ap = ALLOC_ACTION(type);
            ap->type_mask = find_type(arg1);
        }
#endif
#if ENABLE_FEATURE_FIND_PERM
/* -perm mode   File's permission bits are exactly mode (octal or symbolic).
 *              Symbolic modes use mode 0 as a point of departure.
 * -perm -mode  All of the permission bits mode are set for the file.
 * -perm +mode  Any of the permission bits mode are set for the file.
 */
        else if (parm == PARM_perm) {
            action_perm *ap;
            ap = ALLOC_ACTION(perm);
            ap->perm_char = arg1[0];
            arg1 = plus_minus_num(arg1);
            ap->perm_mask = 0;
            if (!bb_parse_mode(arg1, &ap->perm_mask))
                bb_error_msg_and_die("invalid mode: %s", arg1);
        }
#endif
#if ENABLE_FEATURE_FIND_MTIME
        else if (parm == PARM_mtime) {
            action_mtime *ap;
            ap = ALLOC_ACTION(mtime);
            ap->mtime_char = arg1[0];
            ap->mtime_days = xatoul(plus_minus_num(arg1));
        }
#endif
#if ENABLE_FEATURE_FIND_MMIN
        else if (parm == PARM_mmin) {
            action_mmin *ap;
            ap = ALLOC_ACTION(mmin);
            ap->mmin_char = arg1[0];
            ap->mmin_mins = xatoul(plus_minus_num(arg1));
        }
#endif
#if ENABLE_FEATURE_FIND_NEWER
        else if (parm == PARM_newer) {
            struct stat stat_newer;
            action_newer *ap;
            ap = ALLOC_ACTION(newer);
            xstat(arg1, &stat_newer);
            ap->newer_mtime = stat_newer.st_mtime;
        }
#endif
#if ENABLE_FEATURE_FIND_INUM
        else if (parm == PARM_inum) {
            action_inum *ap;
            ap = ALLOC_ACTION(inum);
            ap->inode_num = xatoul(arg1);
        }
#endif
#if ENABLE_FEATURE_FIND_USER
        else if (parm == PARM_user) {
            action_user *ap;
            ap = ALLOC_ACTION(user);
            ap->uid = bb_strtou(arg1, NULL, 10);
            if (errno)
                ap->uid = xuname2uid(arg1);
        }
#endif
#if ENABLE_FEATURE_FIND_GROUP
        else if (parm == PARM_group) {
            action_group *ap;
            ap = ALLOC_ACTION(group);
            ap->gid = bb_strtou(arg1, NULL, 10);
            if (errno)
                ap->gid = xgroup2gid(arg1);
        }
#endif
#if ENABLE_FEATURE_FIND_SIZE
        else if (parm == PARM_size) {
/* -size n[bckw]: file uses n units of space
 * b (default): units are 512-byte blocks
 * c: 1 byte
 * k: kilobytes
 * w: 2-byte words
 */
#if ENABLE_LFS
#define XATOU_SFX xatoull_sfx
#else
#define XATOU_SFX xatoul_sfx
#endif
            static const struct suffix_mult find_suffixes[] = {
                { "c", 1 },
                { "w", 2 },
                { "", 512 },
                { "b", 512 },
                { "k", 1024 },
                { }
            };
            action_size *ap;
            ap = ALLOC_ACTION(size);
            ap->size_char = arg1[0];
            ap->size = XATOU_SFX(plus_minus_num(arg1), find_suffixes);
        }
#endif
#if ENABLE_FEATURE_FIND_CONTEXT
        else if (parm == PARM_context) {
            action_context *ap;
            ap = ALLOC_ACTION(context);
            ap->context = NULL;
            /* SELinux headers erroneously declare non-const parameter */
            if (selinux_raw_to_trans_context((char*)arg1, &ap->context))
                bb_perror_msg("%s", arg1);
        }
#endif
        else {
            bb_error_msg("unrecognized: %s", arg);
            bb_show_usage();
        }
        argv++;
    }
    return appp;
#undef ALLOC_ACTION
}


int find_main(int argc, char **argv);
int find_main(int argc, char **argv)
{
    static const char options[] ALIGN1 =
                      "-follow\0"
USE_FEATURE_FIND_XDEV(    "-xdev\0"    )
USE_FEATURE_FIND_MAXDEPTH("-maxdepth\0")
                      ;
    enum {
                      OPT_FOLLOW,
USE_FEATURE_FIND_XDEV(    OPT_XDEV    ,)
USE_FEATURE_FIND_MAXDEPTH(OPT_MAXDEPTH,)
    };

    char *arg;
    char **argp;
    int i, firstopt, status = EXIT_SUCCESS;
#if ENABLE_FEATURE_FIND_MAXDEPTH
    int maxdepth = INT_MAX;
#endif

    for (firstopt = 1; firstopt < argc; firstopt++) {
        if (argv[firstopt][0] == '-')
            break;
        if (ENABLE_FEATURE_FIND_NOT && LONE_CHAR(argv[firstopt], '!'))
            break;
#if ENABLE_FEATURE_FIND_PAREN
        if (LONE_CHAR(argv[firstopt], '('))
            break;
#endif
    }
    if (firstopt == 1) {
        argv[0] = (char*)".";
        argv--;
        firstopt++;
    }

/* All options always return true. They always take effect
 * rather than being processed only when their place in the
 * expression is reached.
 * We implement: -follow, -xdev, -maxdepth
 */
    /* Process options, and replace then with -a */
    /* (-a will be ignored by recursive parser later) */
    argp = &argv[firstopt];
    while ((arg = argp[0])) {
        int opt = index_in_strings(options, arg);
        if (opt == OPT_FOLLOW) {
            recurse_flags |= ACTION_FOLLOWLINKS;
            argp[0] = (char*)"-a";
        }
#if ENABLE_FEATURE_FIND_XDEV
        if (opt == OPT_XDEV) {
            struct stat stbuf;
            if (!xdev_count) {
                xdev_count = firstopt - 1;
                xdev_dev = xmalloc(xdev_count * sizeof(dev_t));
                for (i = 1; i < firstopt; i++) {
                    /* not xstat(): shouldn't bomb out on
                     * "find not_exist exist -xdev" */
                    if (stat(argv[i], &stbuf))
                        stbuf.st_dev = -1L;
                    xdev_dev[i-1] = stbuf.st_dev;
                }
            }
            argp[0] = (char*)"-a";
        }
#endif
#if ENABLE_FEATURE_FIND_MAXDEPTH
        if (opt == OPT_MAXDEPTH) {
            if (!argp[1])
                bb_show_usage();
            maxdepth = xatoi_u(argp[1]);
            argp[0] = (char*)"-a";
            argp[1] = (char*)"-a";
            argp++;
        }
#endif
        argp++;
    }

    actions = parse_params(&argv[firstopt]);

    for (i = 1; i < firstopt; i++) {
        if (!recursive_action(argv[i],
                recurse_flags,  /* flags */
                fileAction,     /* file action */
                fileAction,     /* dir action */
#if ENABLE_FEATURE_FIND_MAXDEPTH
                /* double cast suppresses
                 * "cast to ptr from int of different size" */
                (void*)(ptrdiff_t)maxdepth,/* user data */
#else
                NULL,           /* user data */
#endif
                0))             /* depth */
            status = EXIT_FAILURE;
    }
    return status;
}