ucx: ucx/memstream.c@76caac0da4a0 (annotated)

ucx/memstream.c@76caac0da4a0 (annotated)

ucx/memstream.c

Tue, 09 Oct 2012 15:02:40 +0200

author: Mike Becker <universe@uap-core.de>
date: Tue, 09 Oct 2012 15:02:40 +0200
changeset 56: 76caac0da4a0
child 57: e18157c52985
permissions: -rw-r--r--

added memstream to ucx - still little work to do

 #include "memstream.h"
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 struct _UcxMemstream {
     void *space;
     size_t pos;
     size_t length;
     _Bool autofree;
 };
 UcxMemstream *ucx_memopen(void* space, size_t length) {
     UcxMemstream *stream = (UcxMemstream*) malloc(sizeof(UcxMemstream));
     if (stream) {
         if (!space) {
             stream->space = malloc(length);
             if (!stream->space) {
                 free(stream);
                 return NULL;
             }
             memset(stream->space, 0, length);
             stream->autofree = 1;
         } else {
             stream->space = space;
             stream->autofree = 0;
         }
         stream->length = length;
         stream->pos = 0;
     }
     return stream;
 }
 void ucx_memclose(UcxMemstream *stream) {
     if (stream->autofree) {
         free(stream->space);
     }
     free(stream);
 }
 int ucx_memseek(UcxMemstream *stream, long offset, int whence) {
     size_t npos;
     switch (whence) {
     case SEEK_SET:
         npos = 0;
         break;
     case SEEK_CUR:
         npos = stream->pos;
         break;
     case SEEK_END:
         npos = strlen(stream->space);
         break;
     }
     npos += offset;
     if (npos < 0 || npos > stream->length) {
         return -1;
     } else {
         stream->pos = npos;
         return 0;
     }
 }
 int ucx_memeof(UcxMemstream *stream) {
     return stream->pos >= stream->length;
 }
 int ucx_memoverflow(UcxMemstream *stream) {
     return stream->pos > stream->length;
 }
 size_t ucx_memtell(UcxMemstream *stream) {
     return stream->pos;
 }
 size_t ucx_memio(void* d, size_t s, size_t n, UcxMemstream *m, _Bool read) {
     size_t len;
     if (m->pos + s*n > m->length) {
         if (ucx_memoverflow(m)) {
             len = 0;
         } else {
             len = m->length - m->pos;
             if (s > 1) len -= len%s;
         }
     } else {
         len = s*n;
     }
     if (len == 0) {
         return 0;
     }
     if (read) {
         memcpy(d, m->space+m->pos, len);
     } else {
         memcpy(m->space+m->pos, d, len);
     }
     m->pos += len;
     return len;
 }
 int ucx_memputc(UcxMemstream *stream, int c) {
     if (ucx_memeof(stream)) {
         return EOF;
     } else {
         c &= 0xFF;
         ((char*)(stream->space))[stream->pos] = (char) c;
         stream->pos++;
         return c;
     }
 }
 int ucx_memgetc(UcxMemstream *stream) {
     if (ucx_memeof(stream)) {
         return EOF;
     } else {
         int c = ((char*)(stream->space))[stream->pos];
         stream->pos++;
         return c;
     }
 }
 int ucx_memprintf(UcxMemstream *stream, const char* format, ...) {
     va_list v;
     va_start(v, format);
     int r = vsprintf(stream->space+stream->pos, format, v);
     va_end(v);
     stream->pos += r;
     return r;
 }
 int ucx_memscanf(UcxMemstream *stream, const char* format, ...) {
     /* TODO: vsscanf returns the number of fields read,
      * we need the number of bytes */
     va_list v;
     va_start(v, format);
     int r = vsscanf(stream->space+stream->pos, format, v);
     va_end(v);
     stream->pos += r;
     return r;
 }

Mercurial > hg > ucx / annotate

ucx/memstream.c@76caac0da4a0 (annotated)

ucx/memstream.c