universe@39: /*
universe@39:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
universe@39:  *
universe@39:  * Copyright 2015 Olaf Wintermann. All rights reserved.
universe@39:  *
universe@39:  * Redistribution and use in source and binary forms, with or without
universe@39:  * modification, are permitted provided that the following conditions are met:
universe@39:  *
universe@39:  *   1. Redistributions of source code must retain the above copyright
universe@39:  *      notice, this list of conditions and the following disclaimer.
universe@39:  *
universe@39:  *   2. Redistributions in binary form must reproduce the above copyright
universe@39:  *      notice, this list of conditions and the following disclaimer in the
universe@39:  *      documentation and/or other materials provided with the distribution.
universe@39:  *
universe@39:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
universe@39:  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
universe@39:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
universe@39:  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
universe@39:  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
universe@39:  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
universe@39:  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
universe@39:  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
universe@39:  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
universe@39:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
universe@39:  * POSSIBILITY OF SUCH DAMAGE.
universe@39:  */
universe@39: 
universe@39: #include "buffer.h"
universe@39: #include <stdarg.h>
universe@39: #include <stdlib.h>
universe@39: #include <string.h>
universe@39: 
universe@39: UcxBuffer *ucx_buffer_new(void *space, size_t capacity, int flags) {
universe@39:     UcxBuffer *buffer = (UcxBuffer*) malloc(sizeof(UcxBuffer));
universe@39:     if (buffer) {
universe@39:         buffer->flags = flags;
universe@39:         if (!space) {
universe@39:             buffer->space = (char*)malloc(capacity);
universe@39:             if (!buffer->space) {
universe@39:                 free(buffer);
universe@39:                 return NULL;
universe@39:             }
universe@39:             memset(buffer->space, 0, capacity);
universe@39:             buffer->flags |= UCX_BUFFER_AUTOFREE;
universe@39:         } else {
universe@39:             buffer->space = (char*)space;
universe@39:         }
universe@39:         buffer->capacity = capacity;
universe@39:         buffer->size = 0;
universe@39: 
universe@39:         buffer->pos = 0;
universe@39:     }
universe@39: 
universe@39:     return buffer;
universe@39: }
universe@39: 
universe@39: void ucx_buffer_free(UcxBuffer *buffer) {
universe@39:     if ((buffer->flags & UCX_BUFFER_AUTOFREE) == UCX_BUFFER_AUTOFREE) {
universe@39:         free(buffer->space);
universe@39:     }
universe@39:     free(buffer);
universe@39: }
universe@39: 
universe@39: UcxBuffer* ucx_buffer_extract(
universe@39:         UcxBuffer *src, size_t start, size_t length, int flags) {
universe@39:     
universe@39:     if (src->size == 0 || length == 0 || start+length > src->capacity) {
universe@39:         return NULL;
universe@39:     }
universe@39: 
universe@39:     UcxBuffer *dst = (UcxBuffer*) malloc(sizeof(UcxBuffer));
universe@39:     if (dst) {
universe@39:         dst->space = (char*)malloc(length);
universe@39:         if (!dst->space) {
universe@39:             free(dst);
universe@39:             return NULL;
universe@39:         }
universe@39:         dst->capacity = length;
universe@39:         dst->size = length;
universe@39:         dst->flags = flags | UCX_BUFFER_AUTOFREE;
universe@39:         dst->pos = 0;
universe@39:         memcpy(dst->space, src->space+start, length);
universe@39:     }
universe@39:     return dst;
universe@39: }
universe@39: 
universe@39: int ucx_buffer_seek(UcxBuffer *buffer, off_t offset, int whence) {
universe@39:     size_t npos;
universe@39:     switch (whence) {
universe@39:     case SEEK_CUR:
universe@39:         npos = buffer->pos;
universe@39:         break;
universe@39:     case SEEK_END:
universe@39:         npos = buffer->size;
universe@39:         break;
universe@39:     case SEEK_SET:
universe@39:         npos = 0;
universe@39:         break;
universe@39:     default:
universe@39:         return -1;
universe@39:     }
universe@39: 
universe@39:     size_t opos = npos;
universe@39:     npos += offset;
universe@39:     
universe@39:     if ((offset > 0 && npos < opos) || (offset < 0 && npos > opos)) {
universe@39:         return -1;
universe@39:     }
universe@39:     
universe@39:     if (npos >= buffer->size) {
universe@39:         return -1;
universe@39:     } else {
universe@39:         buffer->pos = npos;
universe@39:         return 0;
universe@39:     }
universe@39: 
universe@39: }
universe@39: 
universe@39: int ucx_buffer_eof(UcxBuffer *buffer) {
universe@39:     return buffer->pos >= buffer->size;
universe@39: }
universe@39: 
universe@39: int ucx_buffer_extend(UcxBuffer *buffer, size_t len) {
universe@39:     size_t newcap = buffer->capacity;
universe@39:     
universe@39:     if (buffer->capacity + len < buffer->capacity) {
universe@39:         return -1;
universe@39:     }
universe@39:     
universe@39:     while (buffer->capacity + len > newcap) {
universe@39:         newcap <<= 1;
universe@39:         if (newcap < buffer->capacity) {
universe@39:             return -1;
universe@39:         }
universe@39:     }
universe@39:     
universe@39:     char *newspace = (char*)realloc(buffer->space, newcap);
universe@39:     if (newspace) {
universe@39:         memset(newspace+buffer->size, 0, newcap-buffer->size);
universe@39:         buffer->space = newspace;
universe@39:         buffer->capacity = newcap;
universe@39:     } else {
universe@39:         return -1;
universe@39:     }
universe@39:     
universe@39:     return 0;
universe@39: }
universe@39: 
universe@39: size_t ucx_buffer_write(const void *ptr, size_t size, size_t nitems,
universe@39:         UcxBuffer *buffer) {
universe@39:     size_t len = size * nitems;
universe@39:     size_t required = buffer->pos + len;
universe@39:     if (buffer->pos > required) {
universe@39:         return 0;
universe@39:     }
universe@39:     
universe@39:     if (required > buffer->capacity) {
universe@39:         if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
universe@39:             if (ucx_buffer_extend(buffer, required - buffer->capacity)) {
universe@39:                 return 0;
universe@39:             }
universe@39:         } else {
universe@39:             len = buffer->capacity - buffer->pos;
universe@39:             if (size > 1) {
universe@39:                 len -= len%size;
universe@39:             }
universe@39:         }
universe@39:     }
universe@39:     
universe@39:     if (len == 0) {
universe@39:         return len;
universe@39:     }
universe@39:     
universe@39:     memcpy(buffer->space + buffer->pos, ptr, len);
universe@39:     buffer->pos += len;
universe@39:     if(buffer->pos > buffer->size) {
universe@39:         buffer->size = buffer->pos;
universe@39:     }
universe@39:     
universe@39:     return len / size;
universe@39: }
universe@39: 
universe@39: size_t ucx_buffer_read(void *ptr, size_t size, size_t nitems,
universe@39:         UcxBuffer *buffer) {
universe@39:     size_t len = size * nitems;
universe@39:     if (buffer->pos + len > buffer->size) {
universe@39:         len = buffer->size - buffer->pos;
universe@39:         if (size > 1) len -= len%size;
universe@39:     }
universe@39:     
universe@39:     if (len <= 0) {
universe@39:         return len;
universe@39:     }
universe@39:     
universe@39:     memcpy(ptr, buffer->space + buffer->pos, len);
universe@39:     buffer->pos += len;
universe@39:     
universe@39:     return len / size;
universe@39: }
universe@39: 
universe@39: int ucx_buffer_putc(UcxBuffer *buffer, int c) {
universe@39:     if(buffer->pos >= buffer->capacity) {
universe@39:         if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
universe@39:             if(ucx_buffer_extend(buffer, 1)) {
universe@39:                 return EOF;
universe@39:             }
universe@39:         } else {
universe@39:             return EOF;
universe@39:         }
universe@39:     }
universe@39:     
universe@39:     c &= 0xFF;
universe@39:     buffer->space[buffer->pos] = (char) c;
universe@39:     buffer->pos++;
universe@39:     if(buffer->pos > buffer->size) {
universe@39:         buffer->size = buffer->pos;
universe@39:     }
universe@39:     return c;
universe@39: }
universe@39: 
universe@39: int ucx_buffer_getc(UcxBuffer *buffer) {
universe@39:     if (ucx_buffer_eof(buffer)) {
universe@39:         return EOF;
universe@39:     } else {
universe@39:         int c = buffer->space[buffer->pos];
universe@39:         buffer->pos++;
universe@39:         return c;
universe@39:     }
universe@39: }
universe@39: 
universe@39: size_t ucx_buffer_puts(UcxBuffer *buffer, char *str) {
universe@39:     return ucx_buffer_write((const void*)str, 1, strlen(str), buffer);
universe@39: }