ucx/buffer.c

Thu, 28 Feb 2013 08:50:24 +0100

author
Mike Becker <universe@uap-core.de>
date
Thu, 28 Feb 2013 08:50:24 +0100
changeset 103
08018864fb91
parent 95
ecfdc1c4a552
child 140
15f871f50bfd
permissions
-rw-r--r--

added license and copyright notice to all files

     1 /*
     2  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
     3  *
     4  * Copyright 2013 Olaf Wintermann. All rights reserved.
     5  *
     6  * Redistribution and use in source and binary forms, with or without
     7  * modification, are permitted provided that the following conditions are met:
     8  *
     9  *   1. Redistributions of source code must retain the above copyright
    10  *      notice, this list of conditions and the following disclaimer.
    11  *
    12  *   2. Redistributions in binary form must reproduce the above copyright
    13  *      notice, this list of conditions and the following disclaimer in the
    14  *      documentation and/or other materials provided with the distribution.
    15  *
    16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
    20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    26  * POSSIBILITY OF SUCH DAMAGE.
    27  */
    29 #include "buffer.h"
    30 #include <stdarg.h>
    31 #include <stdlib.h>
    32 #include <string.h>
    34 UcxBuffer *ucx_buffer_new(void *space, size_t size, int flags) {
    35     UcxBuffer *buffer = (UcxBuffer*) malloc(sizeof(UcxBuffer));
    36     if (buffer) {
    37         buffer->flags = flags;
    38         if (!space) {
    39             buffer->space = (char*)malloc(size);
    40             if (!buffer->space) {
    41                 free(buffer);
    42                 return NULL;
    43             }
    44             memset(buffer->space, 0, size);
    45             buffer->flags |= UCX_BUFFER_AUTOFREE;
    46         } else {
    47             buffer->space = (char*)space;
    48         }
    49         buffer->capacity = size;
    50         buffer->size = 0;
    52         buffer->pos = 0;
    53     }
    55     return buffer;
    56 }
    58 void ucx_buffer_free(UcxBuffer *buffer) {
    59     if ((buffer->flags & UCX_BUFFER_AUTOFREE) == UCX_BUFFER_AUTOFREE) {
    60         free(buffer->space);
    61     }
    62     free(buffer);
    63 }
    65 UcxBuffer* ucx_buffer_extract(
    66         UcxBuffer *src, size_t start, size_t length, int flags) {
    67     if(src->size == 0) {
    68         return NULL;
    69     }
    70     if (length == 0) {
    71         length = src->size - start;
    72     }
    73     if (start+length > src->size) {
    74         return NULL;
    75     }
    77     UcxBuffer *dst = (UcxBuffer*) malloc(sizeof(UcxBuffer));
    78     if (dst) {
    79         dst->space = (char*)malloc(length);
    80         if (!dst->space) {
    81             free(dst);
    82             return NULL;
    83         }
    84         dst->capacity = length;
    85         dst->size = length;
    86         dst->flags = flags | UCX_BUFFER_AUTOFREE;
    87         dst->pos = 0;
    88         memcpy(dst->space, src->space+start, length);
    89     }
    90     return dst;
    91 }
    93 int ucx_buffer_seek(UcxBuffer *buffer, off_t offset, int whence) {
    94     size_t npos = 0;
    95     switch (whence) {
    96     case SEEK_SET:
    97         npos = 0;
    98         break;
    99     case SEEK_CUR:
   100         npos = buffer->pos;
   101         break;
   102     case SEEK_END:
   103         npos = buffer->size;
   104         break;
   105     }
   107     npos += offset;
   109     if (npos > buffer->size) {
   110         return -1;
   111     } else {
   112         buffer->pos = npos;
   113         return 0;
   114     }
   116 }
   118 int ucx_buffer_eof(UcxBuffer *buffer) {
   119     return buffer->pos >= buffer->size;
   120 }
   122 int ucx_buffer_extend(UcxBuffer *buffer, size_t len) {
   123     size_t newcap = buffer->capacity;
   124     while (buffer->pos + len > newcap) newcap <<= 1;
   126     char *newspace = (char*)realloc(buffer->space, newcap);
   127     if (newspace) {
   128         memset(newspace+buffer->size, 0, newcap-buffer->size);
   129         buffer->space = newspace;
   130         buffer->capacity = newcap;
   131     } else {
   132         return -1;
   133     }
   135     return 0;
   136 }
   138 size_t ucx_buffer_write(const void *ptr, size_t size, size_t nitems,
   139         UcxBuffer *buffer) {
   140     size_t len = size * nitems;
   141     if (buffer->pos + len > buffer->capacity) {
   142         if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
   143             if(ucx_buffer_extend(buffer, len)) {
   144                 return -1;
   145             }
   146         } else {
   147             len = buffer->capacity - buffer->pos;
   148             if (size > 1) len -= len%size;
   149         }
   150     }
   152     if (len <= 0) {
   153         return len;
   154     }
   156     memcpy(buffer->space + buffer->pos, ptr, len);
   157     buffer->pos += len;
   158     if(buffer->pos > buffer->size) {
   159         buffer->size = buffer->pos;
   160     }
   162     return len / size;
   163 }
   165 size_t ucx_buffer_read(void *ptr, size_t size, size_t nitems,
   166         UcxBuffer *buffer) {
   167     size_t len = size * nitems;
   168     if (buffer->pos + len > buffer->size) {
   169         len = buffer->size - buffer->pos;
   170         if (size > 1) len -= len%size;
   171     }
   173     if (len <= 0) {
   174         return len;
   175     }
   177     memcpy(ptr, buffer->space + buffer->pos, len);
   178     buffer->pos += len;
   180     return len / size;
   181 }
   183 int ucx_buffer_putc(UcxBuffer *buffer, int c) {
   184     if(buffer->pos >= buffer->capacity) {
   185         if ((buffer->flags & UCX_BUFFER_AUTOEXTEND) == UCX_BUFFER_AUTOEXTEND) {
   186             if(ucx_buffer_extend(buffer, 1)) {
   187                 return EOF;
   188             }
   189         } else {
   190             return EOF;
   191         }
   192     }
   194     c &= 0xFF;
   195     buffer->space[buffer->pos] = (char) c;
   196     buffer->pos++;
   197     if(buffer->pos > buffer->size) {
   198         buffer->size = buffer->pos;
   199     }
   200     return c;
   201 }
   203 int ucx_buffer_getc(UcxBuffer *buffer) {
   204     if (ucx_buffer_eof(buffer)) {
   205         return EOF;
   206     } else {
   207         int c = buffer->space[buffer->pos];
   208         buffer->pos++;
   209         return c;
   210     }
   211 }
   213 size_t ucx_buffer_generic_copy(void *s1, void *s2,
   214         read_func readfnc, write_func writefnc, size_t bufsize) {
   215     size_t ncp = 0;
   216     char *buf = (char*)malloc(bufsize);
   217     if(buf == NULL) {
   218         return 0;
   219     }
   221     size_t r;
   222     while((r = readfnc(buf, 1, bufsize, s1)) != 0) {
   223         r = writefnc(buf, 1, r, s2);
   224         ncp += r;
   225         if(r == 0) {
   226             break;
   227         }
   228     }
   230     free(buf);
   231     return ncp;
   232 }
   234 size_t ucx_buffer_generic_ncopy(void *s1, void *s2,
   235         read_func readfnc, write_func writefnc, size_t bufsize, size_t n) {
   236     if(n == 0) {
   237         return 0;
   238     }
   240     size_t ncp = 0;
   241     char *buf = (char*)malloc(bufsize);
   242     if(buf == NULL) {
   243         return 0;
   244     }
   246     size_t r;
   247     size_t rn = bufsize > n ? n : bufsize;
   248     while((r = readfnc(buf, 1, rn, s1)) != 0) {
   249         r = writefnc(buf, 1, r, s2);
   250         ncp += r;
   251         n -= r;
   252         rn = bufsize > n ? n : bufsize;
   253         if(r == 0 || n == 0) {
   254             break;
   255         }
   256     }
   258     free(buf);
   259     return ncp;
   260 }

mercurial