--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/ucx/buffer.c Wed Dec 09 11:32:01 2020 +0100
@@ -0,0 +1,297 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2017 Mike Becker, Olaf Wintermann All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "ucx/buffer.h"
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+
+UcxBuffer *ucx_buffer_new(void *space, size_t capacity, int flags) {
+ UcxBuffer *buffer = (UcxBuffer*) malloc(sizeof(UcxBuffer));
+ if (buffer) {
+ buffer->flags = flags;
+ if (!space) {
+ buffer->space = (char*)malloc(capacity);
+ if (!buffer->space) {
+ free(buffer);
+ return NULL;
+ }
+ memset(buffer->space, 0, capacity);
+ buffer->flags |= UCX_BUFFER_AUTOFREE;
+ } else {
+ buffer->space = (char*)space;
+ }
+ buffer->capacity = capacity;
+ buffer->size = 0;
+
+ buffer->pos = 0;
+ }
+
+ return buffer;
+}
+
+void ucx_buffer_free(UcxBuffer *buffer) {
+ if ((buffer->flags & UCX_BUFFER_AUTOFREE) == UCX_BUFFER_AUTOFREE) {
+ free(buffer->space);
+ }
+ free(buffer);
+}
+
+UcxBuffer* ucx_buffer_extract(
+ UcxBuffer *src, size_t start, size_t length, int flags) {
+ if (src->size == 0 || length == 0 ||
+ ((size_t)-1) - start < length || start+length > src->capacity)
+ {
+ return NULL;
+ }
+
+ UcxBuffer *dst = (UcxBuffer*) malloc(sizeof(UcxBuffer));
+ if (dst) {
+ dst->space = (char*)malloc(length);
+ if (!dst->space) {
+ free(dst);
+ return NULL;
+ }
+ dst->capacity = length;
+ dst->size = length;
+ dst->flags = flags | UCX_BUFFER_AUTOFREE;
+ dst->pos = 0;
+ memcpy(dst->space, src->space+start, length);
+ }
+ return dst;
+}
+
+int ucx_buffer_seek(UcxBuffer *buffer, off_t offset, int whence) {
+ size_t npos;
+ switch (whence) {
+ case SEEK_CUR:
+ npos = buffer->pos;
+ break;
+ case SEEK_END:
+ npos = buffer->size;
+ break;
+ case SEEK_SET:
+ npos = 0;
+ break;
+ default:
+ return -1;
+ }
+
+ size_t opos = npos;
+ npos += offset;
+
+ if ((offset > 0 && npos < opos) || (offset < 0 && npos > opos)) {
+ return -1;
+ }
+
+ if (npos >= buffer->size) {
+ return -1;
+ } else {
+ buffer->pos = npos;
+ return 0;
+ }
+
+}
+
+int ucx_buffer_eof(UcxBuffer *buffer) {
+ return buffer->pos >= buffer->size;
+}
+
+int ucx_buffer_extend(UcxBuffer *buffer, size_t len) {
+ size_t newcap = buffer->capacity;
+
+ if (buffer->capacity + len < buffer->capacity) {
+ return -1;
+ }
+
+ while (buffer->capacity + len > newcap) {
+ newcap <<= 1;
+ if (newcap < buffer->capacity) {
+ return -1;
+ }
+ }
+
+ char *newspace = (char*)realloc(buffer->space, newcap);
+ if (newspace) {
+ memset(newspace+buffer->size, 0, newcap-buffer->size);
+ buffer->space = newspace;
+ buffer->capacity = newcap;
+ } else {
+ return -1;
+ }
+
+ return 0;
+}
+
+size_t ucx_buffer_write(const void *ptr, size_t size, size_t nitems,
+ UcxBuffer *buffer) {
+ size_t len;
+ if(ucx_szmul(size, nitems, &len)) {
+ return 0;
+ }
+ size_t required = buffer->pos + len;
+ if (buffer->pos > required) {
+ return 0;
+ }
+
+ if (required > buffer->capacity) {
+ if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
+ if (ucx_buffer_extend(buffer, required - buffer->capacity)) {
+ return 0;
+ }
+ } else {
+ len = buffer->capacity - buffer->pos;
+ if (size > 1) {
+ len -= len%size;
+ }
+ }
+ }
+
+ if (len == 0) {
+ return len;
+ }
+
+ memcpy(buffer->space + buffer->pos, ptr, len);
+ buffer->pos += len;
+ if(buffer->pos > buffer->size) {
+ buffer->size = buffer->pos;
+ }
+
+ return len / size;
+}
+
+size_t ucx_buffer_read(void *ptr, size_t size, size_t nitems,
+ UcxBuffer *buffer) {
+ size_t len;
+ if(ucx_szmul(size, nitems, &len)) {
+ return 0;
+ }
+ if (buffer->pos + len > buffer->size) {
+ len = buffer->size - buffer->pos;
+ if (size > 1) len -= len%size;
+ }
+
+ if (len <= 0) {
+ return len;
+ }
+
+ memcpy(ptr, buffer->space + buffer->pos, len);
+ buffer->pos += len;
+
+ return len / size;
+}
+
+int ucx_buffer_putc(UcxBuffer *buffer, int c) {
+ if(buffer->pos >= buffer->capacity) {
+ if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
+ if(ucx_buffer_extend(buffer, 1)) {
+ return EOF;
+ }
+ } else {
+ return EOF;
+ }
+ }
+
+ c &= 0xFF;
+ buffer->space[buffer->pos] = (char) c;
+ buffer->pos++;
+ if(buffer->pos > buffer->size) {
+ buffer->size = buffer->pos;
+ }
+ return c;
+}
+
+int ucx_buffer_getc(UcxBuffer *buffer) {
+ if (ucx_buffer_eof(buffer)) {
+ return EOF;
+ } else {
+ int c = ((unsigned char*)buffer->space)[buffer->pos];
+ buffer->pos++;
+ return c;
+ }
+}
+
+size_t ucx_buffer_puts(UcxBuffer *buffer, const char *str) {
+ return ucx_buffer_write((const void*)str, 1, strlen(str), buffer);
+}
+
+int ucx_buffer_shift_left(UcxBuffer* buffer, size_t shift) {
+ if (shift >= buffer->size) {
+ buffer->pos = buffer->size = 0;
+ } else {
+ memmove(buffer->space, buffer->space + shift, buffer->size - shift);
+ buffer->size -= shift;
+
+ if (buffer->pos >= shift) {
+ buffer->pos -= shift;
+ } else {
+ buffer->pos = 0;
+ }
+ }
+ return 0;
+}
+
+int ucx_buffer_shift_right(UcxBuffer* buffer, size_t shift) {
+ size_t req_capacity = buffer->size + shift;
+ size_t movebytes;
+
+ // auto extend buffer, if required and enabled
+ if (buffer->capacity < req_capacity) {
+ if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
+ if (ucx_buffer_extend(buffer, req_capacity - buffer->capacity)) {
+ return 1;
+ }
+ movebytes = buffer->size;
+ } else {
+ movebytes = buffer->capacity - shift;
+ }
+ } else {
+ movebytes = buffer->size;
+ }
+
+ memmove(buffer->space + shift, buffer->space, movebytes);
+ buffer->size = shift+movebytes;
+
+ buffer->pos += shift;
+ if (buffer->pos > buffer->size) {
+ buffer->pos = buffer->size;
+ }
+
+ return 0;
+}
+
+int ucx_buffer_shift(UcxBuffer* buffer, off_t shift) {
+ if (shift < 0) {
+ return ucx_buffer_shift_left(buffer, (size_t) (-shift));
+ } else if (shift > 0) {
+ return ucx_buffer_shift_right(buffer, (size_t) shift);
+ } else {
+ return 0;
+ }
+}