/*

     SDL - Simple DirectMedia Layer

     Copyright (C) 1997-2004 Sam Lantinga

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

     modify it under the terms of the GNU Library General Public

     License as published by the Free Software Foundation; either

     version 2 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

     Library General Public License for more details.

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

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

     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

     Sam Lantinga

     slouken@libsdl.org

 */

 #ifdef SAVE_RCSID

 static char rcsid =

  "@(#) $Id$";

 #endif

 /* Not all environments have a working getenv()/putenv() */

 #ifdef TEST_MAIN

 #define NEED_SDL_GETENV

 #endif

 #include "SDL_getenv.h"

 #ifdef NEED_SDL_GETENV

 #include <stdlib.h>

 #include <string.h>

 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 = (char *)malloc(strlen(variable)+1);

 	if ( ! new_variable ) {

 		return(-1);

 	}

 	strcpy(new_variable, variable);

 	/* 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 ( strncmp(SDL_env[i], name, len) == 0 ) {

 				break;

 			}

 		}

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

 		if ( SDL_env[i] ) {

 			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 = 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 {

 			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 = strlen(name);

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

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

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

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

 			}

 		}

 	}

 	return value;

 }

 #endif /* NEED_GETENV */

 #ifdef TEST_MAIN

 #include <stdio.h>

 int main(int argc, char *argv[])

 {

 	char *value;

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

 	fflush(stdout);

 	if ( ! getenv("EXISTS") ) {

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

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

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

 	value = getenv("FIRST");

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

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

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

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

 	value = getenv("SECOND");

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

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

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

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

 	value = getenv("FIRST");

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

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

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

 	fflush(stdout);

 	if ( ! getenv("EXISTS") ) {

 		printf("okay\n");

 	} else {

 		printf("failed\n");

 	}

 	return(0);

 }

 #endif /* TEST_MAIN */