/* Set the locale based on the HTTP_ACCEPT_LANGUAGE variable value sent by
the browser */
void process_language(char * accept_language) {
accept_languages *accept_langs = NULL;
int x;
char locale_string[ 64];
char * locale = NULL;
char * locale_failsafe[] = { "en_US.utf8", "POSIX", "C" };
if(accept_language != NULL) {
accept_langs = parse_accept_languages(accept_language);
}
if(NULL != accept_langs) {
/* Sort the results */
qsort(accept_langs->languages, accept_langs->count,
sizeof(accept_langs->languages[ 0]), compare_accept_languages);
/* Try each language in order of priority */
for(x = 0; ((x < accept_langs->count) && (NULL == locale)); x++) {
snprintf(locale_string, sizeof(locale_string), "%s_%s.%s",
accept_langs->languages[ x]->language,
accept_langs->languages[ x]->locality, "utf8");
locale = setlocale(LC_ALL, locale_string);
}
free_accept_languages(accept_langs);
}
if(NULL == locale) { /* Still isn't set */
/* Try the fail safe locales */
for(x = 0; ((x < (sizeof(locale_failsafe) / sizeof(char *))) &&
(NULL == locale)); x++) {
locale = setlocale(LC_ALL, locale_failsafe[ x]);
}
}
}
accept_languages * parse_accept_languages( char * acceptlang) {
char * langdup; /* Duplicate of accept language for parsing */
accept_languages *langs = NULL;
char * langtok; /* Language token (language + locality + q value) */
char * saveptr; /* Save state of tokenization */
char * qdelim; /* location of the delimiter ';q=' */
char * localitydelim; /* Delimiter for locality specifier */
int x;
char * stp;
/* If the browser did not pass an HTTP_ACCEPT_LANGUAGE variable, there
is not much we can do */
if( NULL == acceptlang) {
return NULL;
}
/* Duplicate the browser supplied HTTP_ACCEPT_LANGUAGE variable */
if( NULL == ( langdup = strdup( acceptlang))) {
printf( "Unable to allocate memory for langdup\n");
return NULL;
}
/* Initialize the structure to contain the parsed HTTP_ACCEPT_LANGUAGE
information */
if( NULL == ( langs = malloc( sizeof( accept_languages)))) {
printf( "Unable to allocate memory for langs\n");
free( langdup);
return NULL;
}
langs->count = 0;
langs->languages = ( accept_language **)NULL;
/* Tokenize the HTTP_ACCEPT_LANGUAGE string */
langtok = strtok_r( langdup, ",", &saveptr);
while( langtok != NULL) {
/* Bump the count and allocate memory for structures */
langs->count++;
if( NULL == langs->languages) {
/* Adding first language */
if( NULL == ( langs->languages =
malloc( langs->count * sizeof( accept_language *)))) {
printf( "Unable to allocate memory for first language\n");
langs->count--;
free_accept_languages( langs);
free( langdup);
return NULL;
}
}
else {
/* Adding additional language */
if( NULL == ( langs->languages = realloc( langs->languages,
langs->count * sizeof( accept_language *)))) {
printf( "Unable to allocate memory for additional language\n");
langs->count--;
free_accept_languages( langs);
free( langdup);
return NULL;
}
}
if( NULL == ( langs->languages[ langs->count - 1] =
malloc( sizeof( accept_language)))) {
printf( "Unable to allocate memory for language\n");
langs->count--;
free_accept_languages( langs);
free( langdup);
return NULL;
}
langs->languages[ langs->count - 1]->language = ( char *)NULL;
langs->languages[ langs->count - 1]->locality = ( char *)NULL;
langs->languages[ langs->count - 1]->q = 1.0;
/* Check to see if there is a q value */
qdelim = strstr( langtok, ACCEPT_LANGUAGE_Q_DELIMITER);
if( NULL != qdelim) { /* found a q value */
langs->languages[ langs->count - 1]->q =
strtod( qdelim + strlen( ACCEPT_LANGUAGE_Q_DELIMITER), NULL);
langtok[ qdelim - langtok] = '\0';
}
/* Check to see if there is a locality specifier */
if( NULL == ( localitydelim = strchr( langtok, '-'))) {
localitydelim = strchr( langtok, '_');
}
if( NULL != localitydelim) {
/* We have a locality delimiter, so copy it */
if( NULL == ( langs->languages[ langs->count - 1]->locality =
strdup( localitydelim + 1))) {
printf( "Unable to allocate memory for locality '%s'\n",
langtok);
free_accept_languages( langs);
free( langdup);
return NULL;
}
/* Ensure it is upper case */
for( x = 0, stp = langs->languages[ langs->count - 1]->locality;
x < (int)strlen( langs->languages[ langs->count - 1]->locality);
x++, stp++) {
*stp = toupper( *stp);
}
/* Then null out the delimiter so the language copy works */
*localitydelim = '\0';
}
if( NULL == ( langs->languages[ langs->count - 1]->language =
strdup( langtok))) {
printf( "Unable to allocate memory for language '%s'\n",
langtok);
free_accept_languages( langs);
free( langdup);
return NULL;
}
/* Get the next language token */
langtok = strtok_r( NULL, ",", &saveptr);
}
free( langdup);
return langs;
}
