SDL_getenv.c File Reference

#include "../SDL_internal.h"
#include "SDL_stdinc.h"

Include dependency graph for SDL_getenv.c:

Go to the source code of this file.

Functions
int	SDL_setenv (const char *name, const char *value, int overwrite)
char *	SDL_getenv (const char *name)

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

Function Documentation

SDL_getenv()

char* SDL_getenv

(

const char *

name

)

Definition at line 219 of file SDL_getenv.c.

{
    int len, i;
    char *value;
 
    /* Input validation */
    if (!name || SDL_strlen(name)==0) {
        return NULL;
    }
    
    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;
}

References i, NULL, SDL_env, SDL_strlen, and SDL_strncmp.

Referenced by SDL_setenv().

SDL_setenv()

int SDL_setenv	(	const char *	name,
		const char *	value,
		int	overwrite
	)

Definition at line 110 of file SDL_getenv.c.

{
    int added;
    int len, i;
    char **new_env;
    char *new_variable;
 
    /* Input validation */
    if (!name || SDL_strlen(name) == 0 || SDL_strchr(name, '=') != NULL || !value) {
        return (-1);
    }
 
    /* See if it already exists */
    if (!overwrite && SDL_getenv(name)) {
        return 0;
    }
 
    /* Allocate memory for the variable */
    len = SDL_strlen(name) + SDL_strlen(value) + 2;
    new_variable = (char *) SDL_malloc(len);
    if (!new_variable) {
        return (-1);
    }
 
    SDL_snprintf(new_variable, len, "%s=%s", name, value);
    value = new_variable + SDL_strlen(name) + 1;
    name = new_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 (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);
}

References i, NULL, SDL_env, SDL_free, SDL_getenv(), SDL_malloc, SDL_realloc, SDL_snprintf, SDL_strchr, SDL_strlen, and SDL_strncmp.

Variable Documentation

SDL_env

char** SDL_env = (char **) 0

static

Definition at line 108 of file SDL_getenv.c.

Referenced by SDL_getenv(), and SDL_setenv().