aosp12/external/kmod/shared/strbuf.c

129 lines
2.5 KiB
C

/*
* libkmod - interface to kernel module operations
*
* Copyright (C) 2011-2013 ProFUSION embedded systems
* Copyright (C) 2014 Intel Corporation. All rights reserved.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include "util.h"
#include "strbuf.h"
#define BUF_STEP 128
static bool buf_grow(struct strbuf *buf, size_t newsize)
{
void *tmp;
size_t sz;
if (newsize <= buf->size)
return true;
if (newsize % BUF_STEP == 0)
sz = newsize;
else
sz = ((newsize / BUF_STEP) + 1) * BUF_STEP;
tmp = realloc(buf->bytes, sz);
if (sz > 0 && tmp == NULL)
return false;
buf->bytes = tmp;
buf->size = sz;
return true;
}
void strbuf_init(struct strbuf *buf)
{
buf->bytes = NULL;
buf->size = 0;
buf->used = 0;
}
void strbuf_release(struct strbuf *buf)
{
free(buf->bytes);
}
char *strbuf_steal(struct strbuf *buf)
{
char *bytes;
bytes = realloc(buf->bytes, buf->used + 1);
if (!bytes) {
free(buf->bytes);
return NULL;
}
bytes[buf->used] = '\0';
return bytes;
}
const char *strbuf_str(struct strbuf *buf)
{
if (!buf_grow(buf, buf->used + 1))
return NULL;
buf->bytes[buf->used] = '\0';
return buf->bytes;
}
bool strbuf_pushchar(struct strbuf *buf, char ch)
{
if (!buf_grow(buf, buf->used + 1))
return false;
buf->bytes[buf->used] = ch;
buf->used++;
return true;
}
unsigned strbuf_pushchars(struct strbuf *buf, const char *str)
{
unsigned int len;
assert(str != NULL);
assert(buf != NULL);
len = strlen(str);
if (!buf_grow(buf, buf->used + len))
return 0;
memcpy(buf->bytes + buf->used, str, len);
buf->used += len;
return len;
}
void strbuf_popchar(struct strbuf *buf)
{
assert(buf->used > 0);
buf->used--;
}
void strbuf_popchars(struct strbuf *buf, unsigned n)
{
assert(buf->used >= n);
buf->used -= n;
}
void strbuf_clear(struct strbuf *buf)
{
buf->used = 0;
}