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/*

 * Commandline option parsing functions

 *

 * Copyright (c) 2003-2008 Fabrice Bellard

 * Copyright (c) 2009 Kevin Wolf <kwolf@redhat.com>

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include <stdio.h>

#include <string.h>

#include "qemu-common.h"

#include "qemu-option.h"

/*

 * Extracts the name of an option from the parameter string (p points at the

 * first byte of the option name)

 *

 * The option name is delimited by delim (usually , or =) or the string end

 * and is copied into buf. If the option name is longer than buf_size, it is

 * truncated. buf is always zero terminated.

 *

 * The return value is the position of the delimiter/zero byte after the option

 * name in p.

 */

const char *get_opt_name(char *buf, int buf_size, const char *p, char delim)

{

    char *q;

    q = buf;

    while (*p != '\0' && *p != delim) {

        if (q && (q - buf) < buf_size - 1)

            *q++ = *p;

        p++;

    }

    if (q)

        *q = '\0';

    return p;

}

/*

 * Extracts the value of an option from the parameter string p (p points at the

 * first byte of the option value)

 *

 * This function is comparable to get_opt_name with the difference that the

 * delimiter is fixed to be comma which starts a new option. To specify an

 * option value that contains commas, double each comma.

 */

const char *get_opt_value(char *buf, int buf_size, const char *p)

{

    char *q;

    q = buf;

    while (*p != '\0') {

        if (*p == ',') {

            if (*(p + 1) != ',')

                break;

            p++;

        }

        if (q && (q - buf) < buf_size - 1)

            *q++ = *p;

        p++;

    }

    if (q)

        *q = '\0';

    return p;

}

/*

 * Searches an option list for an option with the given name

 */

QEMUOptionParameter *get_option_parameter(QEMUOptionParameter *list,

    const char *name)

{

    while (list && list->name) {

        if (!strcmp(list->name, name)) {

            return list;

        }

        list++;

    }

    return NULL;

}

/*

 * Sets the value of a parameter in a given option list. The parsing of the

 * value depends on the type of option:

 *

 * OPT_FLAG (uses value.n):

 *      If no value is given, the flag is set to 1.

 *      Otherwise the value must be "on" (set to 1) or "off" (set to 0)

 *

 * OPT_STRING (uses value.s):

 *      value is strdup()ed and assigned as option value

 *

 * OPT_SIZE (uses value.n):

 *      The value is converted to an integer. Suffixes for kilobytes etc. are

 *      allowed (powers of 1024).

 *

 * Returns 0 on succes, -1 in error cases

 */

int set_option_parameter(QEMUOptionParameter *list, const char *name,

    const char *value)

{

    // Find a matching parameter

    list = get_option_parameter(list, name);

    if (list == NULL) {

        fprintf(stderr, "Unknown option '%s'\n", name);

        return -1;

    }

    // Process parameter

    switch (list->type) {

    case OPT_FLAG:

        if (value != NULL) {

            if (!strcmp(value, "on")) {

                list->value.n = 1;

            } else if (!strcmp(value, "off")) {

                list->value.n = 0;

            } else {

                fprintf(stderr, "Option '%s': Use 'on' or 'off'\n", name);

                return -1;

            }

        } else {

            list->value.n = 1;

        }

        break;

    case OPT_STRING:

        if (value != NULL) {

            list->value.s = strdup(value);

        } else {

            fprintf(stderr, "Option '%s' needs a parameter\n", name);

            return -1;

        }

        break;

    case OPT_SIZE:

        if (value != NULL) {

            double sizef = strtod(value, (char**) &value);

            switch (*value) {

            case 'T':

                sizef *= 1024;

            case 'G':

                sizef *= 1024;

            case 'M':

                sizef *= 1024;

            case 'K':

            case 'k':

                sizef *= 1024;

            case 'b':

            case '\0':

                list->value.n = (uint64_t) sizef;

                break;

            default:

                fprintf(stderr, "Option '%s' needs size as parameter\n", name);

                fprintf(stderr, "You may use k, M, G or T suffixes for "

                    "kilobytes, megabytes, gigabytes and terabytes.\n");

                return -1;

            }

        } else {

            fprintf(stderr, "Option '%s' needs a parameter\n", name);

            return -1;

        }

        break;

    default:

        fprintf(stderr, "Bug: Option '%s' has an unknown type\n", name);

        return -1;

    }

    return 0;

}

/*

 * Sets the given parameter to an integer instead of a string.

 * This function cannot be used to set string options.

 *

 * Returns 0 on success, -1 in error cases

 */

int set_option_parameter_int(QEMUOptionParameter *list, const char *name,

    uint64_t value)

{

    // Find a matching parameter

    list = get_option_parameter(list, name);

    if (list == NULL) {

        fprintf(stderr, "Unknown option '%s'\n", name);

        return -1;

    }

    // Process parameter

    switch (list->type) {

    case OPT_FLAG:

    case OPT_NUMBER:

    case OPT_SIZE:

        list->value.n = value;

        break;

    default:

        return -1;

    }

    return 0;

}

/*

 * Frees a option list. If it contains strings, the strings are freed as well.

 */

void free_option_parameters(QEMUOptionParameter *list)

{

    QEMUOptionParameter *cur = list;

    while (cur && cur->name) {

        if (cur->type == OPT_STRING) {

            free(cur->value.s);

        }

        cur++;

    }

    free(list);

}

/*

 * Parses a parameter string (param) into an option list (dest).

 *

 * list is the templace is. If dest is NULL, a new copy of list is created for

 * it. If list is NULL, this function fails.

 *

 * A parameter string consists of one or more parameters, separated by commas.

 * Each parameter consists of its name and possibly of a value. In the latter

 * case, the value is delimited by an = character. To specify a value which

 * contains commas, double each comma so it won't be recognized as the end of

 * the parameter.

 *

 * For more details of the parsing see above.

 *

 * Returns a pointer to the first element of dest (or the newly allocated copy)

 * or NULL in error cases

 */

QEMUOptionParameter *parse_option_parameters(const char *param,

    QEMUOptionParameter *list, QEMUOptionParameter *dest)

{

    QEMUOptionParameter *cur;

    QEMUOptionParameter *allocated = NULL;

    char name[256];

    char value[256];

    char *param_delim, *value_delim;

    char next_delim;

    size_t num_options;

    if (list == NULL) {

        return NULL;

    }

    if (dest == NULL) {

        // Count valid options

        num_options = 0;

        cur = list;

        while (cur->name) {

            num_options++;

            cur++;

        }

        // Create a copy of the option list to fill in values

        dest = qemu_mallocz((num_options + 1) * sizeof(QEMUOptionParameter));

        allocated = dest;

        memcpy(dest, list, (num_options + 1) * sizeof(QEMUOptionParameter));

    }

    while (*param) {

        // Find parameter name and value in the string

        param_delim = strchr(param, ',');

        value_delim = strchr(param, '=');

        if (value_delim && (value_delim < param_delim || !param_delim)) {

            next_delim = '=';

        } else {

            next_delim = ',';

            value_delim = NULL;

        }

        param = get_opt_name(name, sizeof(name), param, next_delim);

        if (value_delim) {

            param = get_opt_value(value, sizeof(value), param + 1);

        }

        if (*param != '\0') {

            param++;

        }

        // Set the parameter

        if (set_option_parameter(dest, name, value_delim ? value : NULL)) {

            goto fail;

        }

    }

    return dest;

fail:

    // Only free the list if it was newly allocated

    free_option_parameters(allocated);

    return NULL;

}

/*

 * Prints all options of a list that have a value to stdout

 */

void print_option_parameters(QEMUOptionParameter *list)

{

    while (list && list->name) {

        switch (list->type) {

            case OPT_STRING:

                 if (list->value.s != NULL) {

                     printf("%s='%s' ", list->name, list->value.s);

                 }

                break;

            case OPT_FLAG:

                printf("%s=%s ", list->name, list->value.n ? "on" : "off");

                break;

            case OPT_SIZE:

            case OPT_NUMBER:

                printf("%s=%" PRId64 " ", list->name, list->value.n);

                break;

            default:

                printf("%s=(unkown type) ", list->name);

                break;

        }

        list++;

    }

}

/*

 * Prints an overview of all available options

 */

void print_option_help(QEMUOptionParameter *list)

{

    printf("Supported options:\n");

    while (list && list->name) {

        printf("%-16s %s\n", list->name,

            list->help ? list->help : "No description available");

        list++;

    }

}