linux-imx

/*

 *  linux/fs/binfmt_script.c

 *

 *  Copyright (C) 1996  Martin von Löwis

 *  original #!-checking implemented by tytso.

 */

​

#include <linux/module.h>

#include <linux/string.h>

#include <linux/stat.h>

#include <linux/binfmts.h>

#include <linux/init.h>

#include <linux/file.h>

#include <linux/err.h>

#include <linux/fs.h>

​

static inline bool spacetab(char c) { return c == ' ' || c == '\t'; }

static inline char *next_non_spacetab(char *first, const char *last)

{

    for (; first <= last; first++)

        if (!spacetab(*first))

            return first;

    return NULL;

}

static inline char *next_terminator(char *first, const char *last)

{

    for (; first <= last; first++)

        if (spacetab(*first) || !*first)

            return first;

    return NULL;

}

​

static int load_script(struct linux_binprm *bprm)

{

    const char *i_arg, *i_name;

    char *cp, *buf_end;

    struct file *file;

    int retval;

​

    /* Not ours to exec if we don't start with "#!". */

    if ((bprm->buf[0] != '#') || (bprm->buf[1] != '!'))

        return -ENOEXEC;

​

    /*

     * If the script filename will be inaccessible after exec, typically

     * because it is a "/dev/fd/<fd>/.." path against an O_CLOEXEC fd, give

     * up now (on the assumption that the interpreter will want to load

     * this file).

     */

    if (bprm->interp_flags & BINPRM_FLAGS_PATH_INACCESSIBLE)

        return -ENOENT;

​

    /* Release since we are not mapping a binary into memory. */

    allow_write_access(bprm->file);

    fput(bprm->file);

    bprm->file = NULL;

​

    /*

     * This section handles parsing the #! line into separate

     * interpreter path and argument strings. We must be careful

     * because bprm->buf is not yet guaranteed to be NUL-terminated

     * (though the buffer will have trailing NUL padding when the

     * file size was smaller than the buffer size).