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/*
* Copyright © 2011 Mozilla Foundation
*
* This program is made available under an ISC-style license. See the
* accompanying file LICENSE for details.
*/
#include "cubeb_strings.h"
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#define CUBEB_STRINGS_INLINE_COUNT 4
struct cubeb_strings {
uint32_t size;
uint32_t count;
char ** data;
char * small_store[CUBEB_STRINGS_INLINE_COUNT];
};
int
cubeb_strings_init(cubeb_strings ** strings)
{
cubeb_strings * strs = NULL;
if (!strings) {
return CUBEB_ERROR;
}
strs = calloc(1, sizeof(cubeb_strings));
assert(strs);
if (!strs) {
return CUBEB_ERROR;
}
strs->size = sizeof(strs->small_store) / sizeof(strs->small_store[0]);
strs->count = 0;
strs->data = strs->small_store;
*strings = strs;
return CUBEB_OK;
}
void
cubeb_strings_destroy(cubeb_strings * strings)
{
char ** sp = NULL;
char ** se = NULL;
if (!strings) {
return;
}
sp = strings->data;
se = sp + strings->count;
for (; sp != se; sp++) {
if (*sp) {
free(*sp);
}
}
if (strings->data != strings->small_store) {
free(strings->data);
}
free(strings);
}
/** Look for string in string storage.
@param strings Opaque pointer to interned string storage.
@param s String to look up.
@retval Read-only string or NULL if not found. */
static char const *
cubeb_strings_lookup(cubeb_strings * strings, char const * s)
{
char ** sp = NULL;
char ** se = NULL;
if (!strings || !s) {
return NULL;
}
sp = strings->data;
se = sp + strings->count;
for (; sp != se; sp++) {
if (*sp && strcmp(*sp, s) == 0) {
return *sp;
}
}
return NULL;
}
static char const *
cubeb_strings_push(cubeb_strings * strings, char const * s)
{
char * is = NULL;
if (strings->count == strings->size) {
char ** new_data;
uint32_t value_size = sizeof(char const *);
uint32_t new_size = strings->size * 2;
if (!new_size || value_size > (uint32_t)-1 / new_size) {
// overflow
return NULL;
}
if (strings->small_store == strings->data) {
// First time heap allocation.
new_data = malloc(new_size * value_size);
if (new_data) {
memcpy(new_data, strings->small_store, sizeof(strings->small_store));
}
} else {
new_data = realloc(strings->data, new_size * value_size);
}
if (!new_data) {
// out of memory
return NULL;
}
strings->size = new_size;
strings->data = new_data;
}
is = strdup(s);
strings->data[strings->count++] = is;
return is;
}
char const *
cubeb_strings_intern(cubeb_strings * strings, char const * s)
{
char const * is = NULL;
if (!strings || !s) {
return NULL;
}
is = cubeb_strings_lookup(strings, s);
if (is) {
return is;
}
return cubeb_strings_push(strings, s);
}