/*

 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * Maintains a list of currently loaded DLLs (Dynamic Link Libraries)

 * and their associated handles. Library names are case-insensitive.

 */

#include <windows.h>

#include <stdio.h>

#include <string.h>

#include <errno.h>

#include <io.h>

#include <stdlib.h>

#include "sys.h"

#include "path_md.h"

static void dll_build_name(char* buffer, size_t buflen,

                           const char* paths, const char* fname) {

    char *path, *paths_copy, *next_token;

    paths_copy = strdup(paths);

    if (paths_copy == NULL) {

        return;

    }

    next_token = NULL;

    path = strtok_s(paths_copy, PATH_SEPARATOR, &next_token);

    while (path != NULL) {

        _snprintf(buffer, buflen, "%s\\%s.dll", path, fname);

        if (_access(buffer, 0) == 0) {

            break;

        }

        *buffer = '\0';

        path = strtok_s(NULL, PATH_SEPARATOR, &next_token);

    }

    free(paths_copy);

}

/*

 * From system_md.c v1.54

 */

int

dbgsysGetLastErrorString(char *buf, int len)

{

    long errval;

    if ((errval = GetLastError()) != 0) {

        /* DOS error */

        int n = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,

                              NULL, errval,

                              0, buf, len, NULL);

        if (n > 3) {

            /* Drop final '.', CR, LF */

            if (buf[n - 1] == '\n') n--;

            if (buf[n - 1] == '\r') n--;

            if (buf[n - 1] == '.') n--;

            buf[n] = '\0';

        }

        return n;

    }

    if (errno != 0) {

        /* C runtime error that has no corresponding DOS error code */

        const char *s = strerror(errno);

        int n = (int)strlen(s);

        if (n >= len) n = len - 1;

        strncpy(buf, s, n);

        buf[n] = '\0';

        return n;

    }

    return 0;

}

/*

 * Build a machine dependent library name out of a path and file name.

 */

void

dbgsysBuildLibName(char *holder, int holderlen, const char *pname, const char *fname)

{

    const int pnamelen = pname ? (int)strlen(pname) : 0;

    *holder = '\0';

    /* Quietly truncates on buffer overflow. Should be an error. */

    if (pnamelen + (int)strlen(fname) + 10 > holderlen) {

        return;

    }

    if (pnamelen == 0) {

        sprintf(holder, "%s.dll", fname);

    } else {

      dll_build_name(holder, holderlen, pname, fname);

    }

}

void *

dbgsysLoadLibrary(const char * name, char *err_buf, int err_buflen)

{

    void *result = LoadLibrary(name);

    if (result == NULL) {

        /* Error message is pretty lame, try to make a better guess. */

        long errcode = GetLastError();

        if (errcode == ERROR_MOD_NOT_FOUND) {

            strncpy(err_buf, "Can't find dependent libraries", err_buflen-2);

            err_buf[err_buflen-1] = '\0';

        } else {

            dbgsysGetLastErrorString(err_buf, err_buflen);

        }

    }

    return result;

}

void dbgsysUnloadLibrary(void *handle)

{

    FreeLibrary(handle);

}

void * dbgsysFindLibraryEntry(void *handle, const char *name)

{

    return GetProcAddress(handle, name);

}