/*

    SDL - Simple DirectMedia Layer

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public

    License as published by the Free Software Foundation; either

    version 2.1 of the License, or (at your option) any later version.

    This library 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

    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public

    License along with this library; if not, write to the Free Software

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

    Sam Lantinga

    slouken@libsdl.org

*/

#include "SDL_config.h"

#include "SDL_stdinc.h"

#ifndef HAVE_GETENV

#if defined(__WIN32__) && !defined(_WIN32_WCE)

#define WIN32_LEAN_AND_MEAN

#include <windows.h>

/* Note this isn't thread-safe! */

static char *SDL_envmem = NULL; /* Ugh, memory leak */

static size_t SDL_envmemlen = 0;

/* Put a variable of the form "name=value" into the environment */

int

SDL_putenv(const char *variable)

{

    size_t bufferlen;

    char *value;

    const char *sep;

    sep = SDL_strchr(variable, '=');

    if (sep == NULL) {

        return -1;

    }

    bufferlen = SDL_strlen(variable) + 1;

    if (bufferlen > SDL_envmemlen) {

        char *newmem = (char *) SDL_realloc(SDL_envmem, bufferlen);

        if (newmem == NULL) {

            return -1;

        }

        SDL_envmem = newmem;

        SDL_envmemlen = bufferlen;

    }

    SDL_strlcpy(SDL_envmem, variable, bufferlen);

    value = SDL_envmem + (sep - variable);

    *value++ = '\0';

    if (!SetEnvironmentVariable(SDL_envmem, *value ? value : NULL)) {

        return -1;

    }

    return 0;

}

/* Retrieve a variable named "name" from the environment */

char *

SDL_getenv(const char *name)

{

    size_t bufferlen;

    bufferlen =

        GetEnvironmentVariable(name, SDL_envmem, (DWORD) SDL_envmemlen);

    if (bufferlen == 0) {

        return NULL;

    }

    if (bufferlen > SDL_envmemlen) {

        char *newmem = (char *) SDL_realloc(SDL_envmem, bufferlen);

        if (newmem == NULL) {

            return NULL;

        }

        SDL_envmem = newmem;

        SDL_envmemlen = bufferlen;

        GetEnvironmentVariable(name, SDL_envmem, (DWORD) SDL_envmemlen);

    }

    return SDL_envmem;

}

#else /* roll our own */

static char **SDL_env = (char **) 0;

/* Put a variable of the form "name=value" into the environment */

int

SDL_putenv(const char *variable)

{

    const char *name, *value;

    int added;

    int len, i;

    char **new_env;

    char *new_variable;

    /* A little error checking */

    if (!variable) {

        return (-1);

    }

    name = variable;

    for (value = variable; *value && (*value != '='); ++value) {

        /* Keep looking for '=' */ ;

    }

    if (*value) {

        ++value;

    } else {

        return (-1);

    }

    /* Allocate memory for the variable */

    new_variable = SDL_strdup(variable);

    if (!new_variable) {

        return (-1);

    }

    /* Actually put it into the environment */

    added = 0;

    i = 0;

    if (SDL_env) {

        /* Check to see if it's already there... */

        len = (value - name);

        for (; SDL_env[i]; ++i) {

            if (SDL_strncmp(SDL_env[i], name, len) == 0) {

                break;

            }

        }

        /* If we found it, just replace the entry */

        if (SDL_env[i]) {

            SDL_free(SDL_env[i]);

            SDL_env[i] = new_variable;

            added = 1;

        }

    }

    /* Didn't find it in the environment, expand and add */

    if (!added) {

        new_env = SDL_realloc(SDL_env, (i + 2) * sizeof(char *));

        if (new_env) {

            SDL_env = new_env;

            SDL_env[i++] = new_variable;

            SDL_env[i++] = (char *) 0;

            added = 1;

        } else {

            SDL_free(new_variable);

        }

    }

    return (added ? 0 : -1);

}

/* Retrieve a variable named "name" from the environment */

char *

SDL_getenv(const char *name)

{

    int len, i;

    char *value;

    value = (char *) 0;

    if (SDL_env) {

        len = SDL_strlen(name);

        for (i = 0; SDL_env[i] && !value; ++i) {

            if ((SDL_strncmp(SDL_env[i], name, len) == 0) &&

                (SDL_env[i][len] == '=')) {

                value = &SDL_env[i][len + 1];

            }

        }

    }

    return value;

}

#endif /* __WIN32__ */

#endif /* !HAVE_GETENV */

#ifdef TEST_MAIN

#include <stdio.h>

int

main(int argc, char *argv[])

{

    char *value;

    printf("Checking for non-existent variable... ");

    fflush(stdout);

    if (!SDL_getenv("EXISTS")) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Setting FIRST=VALUE1 in the environment... ");

    fflush(stdout);

    if (SDL_putenv("FIRST=VALUE1") == 0) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Getting FIRST from the environment... ");

    fflush(stdout);

    value = SDL_getenv("FIRST");

    if (value && (SDL_strcmp(value, "VALUE1") == 0)) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Setting SECOND=VALUE2 in the environment... ");

    fflush(stdout);

    if (SDL_putenv("SECOND=VALUE2") == 0) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Getting SECOND from the environment... ");

    fflush(stdout);

    value = SDL_getenv("SECOND");

    if (value && (SDL_strcmp(value, "VALUE2") == 0)) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Setting FIRST=NOVALUE in the environment... ");

    fflush(stdout);

    if (SDL_putenv("FIRST=NOVALUE") == 0) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Getting FIRST from the environment... ");

    fflush(stdout);

    value = SDL_getenv("FIRST");

    if (value && (SDL_strcmp(value, "NOVALUE") == 0)) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    printf("Checking for non-existent variable... ");

    fflush(stdout);

    if (!SDL_getenv("EXISTS")) {

        printf("okay\n");

    } else {

        printf("failed\n");

    }

    return (0);

}

#endif /* TEST_MAIN */

/* vi: set ts=4 sw=4 expandtab: */