/**

 * \file file.c

 *

 * Handle options that have file names for arguments.

 *

 * @addtogroup autoopts

 * @{

 */

/*

 *  This file is part of AutoOpts, a companion to AutoGen.

 *  AutoOpts is free software.

 *  AutoOpts is Copyright (C) 1992-2015 by Bruce Korb - all rights reserved

 *

 *  AutoOpts is available under any one of two licenses.  The license

 *  in use must be one of these two and the choice is under the control

 *  of the user of the license.

 *

 *   The GNU Lesser General Public License, version 3 or later

 *      See the files "COPYING.lgplv3" and "COPYING.gplv3"

 *

 *   The Modified Berkeley Software Distribution License

 *      See the file "COPYING.mbsd"

 *

 *  These files have the following sha256 sums:

 *

 *  8584710e9b04216a394078dc156b781d0b47e1729104d666658aecef8ee32e95  COPYING.gplv3

 *  4379e7444a0e2ce2b12dd6f5a52a27a4d02d39d247901d3285c88cf0d37f477b  COPYING.lgplv3

 *  13aa749a5b0a454917a944ed8fffc530b784f5ead522b1aacaf4ec8aa55a6239  COPYING.mbsd

 */

/**

 *  Make sure the directory containing the subject file exists and that

 *  the file exists or does not exist, per the option requirements.

 *

 * @param ftype file existence type flags

 * @param pOpts program option descriptor

 * @param pOD   the option descriptor

 */

static void

check_existence(teOptFileType ftype, tOptions * pOpts, tOptDesc * pOD)

{

    char const * fname = pOD->optArg.argString;

    struct stat sb;

    errno = 0;

    switch (ftype & FTYPE_MODE_EXIST_MASK) {

    case FTYPE_MODE_MUST_NOT_EXIST:

        if ((stat(fname, &sb) == 0) || (errno != ENOENT)) {

            if (errno == 0)

                errno = EINVAL;

            fserr_exit(pOpts->pzProgName, "stat", fname);

            /* NOTREACHED */

        }

        /* FALLTHROUGH */

    default:

    case FTYPE_MODE_MAY_EXIST:

    {

        char * p = strrchr(fname, DIRCH);

        size_t l;

        if (p == NULL)

            /*

             *  The file may or may not exist and its directory is ".".

             *  Assume that "." exists.

             */

            break;

        l = (size_t)(p - fname);

        p = AGALOC(l + 1, "fname");

        memcpy(p, fname, l);

        p[l] = NUL;

        if ((stat(p, &sb) != 0) || (errno = EINVAL, ! S_ISDIR(sb.st_mode)))

            fserr_exit(pOpts->pzProgName, "stat", p);

            /* NOTREACHED */

        AGFREE(p);

        break;

    }

    case FTYPE_MODE_MUST_EXIST:

        if (  (stat(fname, &sb) != 0)

           || (errno = EINVAL, ! S_ISREG(sb.st_mode))  )

            fserr_exit(pOpts->pzProgName, "stat", fname);

            /* NOTREACHED */

        break;

    }

}

/**

 *  Open the specified file with open(2) and save the FD.

 *

 * @param pOpts program option descriptor

 * @param pOD   the option descriptor

 * @param mode  the open mode (uses int flags value)

 */

static void

open_file_fd(tOptions * pOpts, tOptDesc * pOD, tuFileMode mode)

{

    int fd = open(pOD->optArg.argString, mode.file_flags);

    if (fd < 0)

        fserr_exit(pOpts->pzProgName, "open", pOD->optArg.argString);

        /* NOTREACHED */

    if ((pOD->fOptState & OPTST_ALLOC_ARG) != 0)

        pOD->optCookie = VOIDP(pOD->optArg.argString);

    else

        AGDUPSTR(pOD->optCookie, pOD->optArg.argString, "file name");

    pOD->optArg.argFd = fd;

    pOD->fOptState &= ~OPTST_ALLOC_ARG;

}

/**

 *  Open the specified file with open(2) and save the FD.

 *

 * @param pOpts program option descriptor

 * @param pOD   the option descriptor

 * @param mode  the open mode (uses "char *" mode value)

 */

static void

fopen_file_fp(tOptions * pOpts, tOptDesc * pOD, tuFileMode mode)

{

    FILE * fp = fopen(pOD->optArg.argString, mode.file_mode);

    if (fp == NULL)

        fserr_exit(pOpts->pzProgName, "fopen", pOD->optArg.argString);

        /* NOTREACHED */

    if ((pOD->fOptState & OPTST_ALLOC_ARG) != 0)

        pOD->optCookie = VOIDP(pOD->optArg.argString);

    else

        AGDUPSTR(pOD->optCookie, pOD->optArg.argString, "file name");

    pOD->optArg.argFp = fp;

    pOD->fOptState &= ~OPTST_ALLOC_ARG;

}

/*=export_func  optionFileCheck

 * private:

 *

 * what:  Decipher a boolean value

 * arg:   + tOptions *    + pOpts    + program options descriptor  +

 * arg:   + tOptDesc *    + pOptDesc + the descriptor for this arg +

 * arg:   + teOptFileType + ftype    + File handling type          +

 * arg:   + tuFileMode    + mode     + file open mode (if needed)  +

 *

 * doc:

 *   Make sure the named file conforms with the file type mode.

 *   The mode specifies if the file must exist, must not exist or may

 *   (or may not) exist.  The mode may also specify opening the

 *   file: don't, open just the descriptor (fd), or open as a stream

 *   (FILE * pointer).

=*/

void

optionFileCheck(tOptions * pOpts, tOptDesc * pOD,

                teOptFileType ftype, tuFileMode mode)

{

    if (pOpts <= OPTPROC_EMIT_LIMIT) {

        if (pOpts != OPTPROC_EMIT_USAGE)

            return;

        switch (ftype & FTYPE_MODE_EXIST_MASK) {

        case FTYPE_MODE_MUST_NOT_EXIST:

            fputs(zFileCannotExist + tab_skip_ct, option_usage_fp);

            break;

        case FTYPE_MODE_MUST_EXIST:

            fputs(zFileMustExist + tab_skip_ct, option_usage_fp);

            break;

        }

        return;

    }

    if ((pOD->fOptState & OPTST_RESET) != 0) {

        if (pOD->optCookie != NULL)

            AGFREE(pOD->optCookie);

        return;

    }

    check_existence(ftype, pOpts, pOD);

    switch (ftype & FTYPE_MODE_OPEN_MASK) {

    default:

    case FTYPE_MODE_NO_OPEN:  break;

    case FTYPE_MODE_OPEN_FD:  open_file_fd( pOpts, pOD, mode); break;

    case FTYPE_MODE_FOPEN_FP: fopen_file_fp(pOpts, pOD, mode); break;

    }

}

/** @}

 *

 * Local Variables:

 * mode: C

 * c-file-style: "stroustrup"

 * indent-tabs-mode: nil

 * End:

 * end of autoopts/file.c */