/
fbufopen.c
executable file
·88 lines (68 loc) · 1.72 KB
/
fbufopen.c
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// Buffer memory handler based on fmemopen for MAC
//
// There is a problem about flag EOF in reading streams in fortran
//
// Program created 22, March, 2020. ROR.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "fbufopen.h"
int readfn(void *handler, char *buf, int size) {
fbuf_t *mem = handler;
size_t available = mem->size - mem->pos;
if (size > available) {
size = available;
}
memcpy(buf, (mem->buffer)+(mem->pos), sizeof(char) * size);
mem->pos += size+1;
return size;
}
int writefn(void *handler, const char *buf, int size) {
fbuf_t *mem = handler;
size_t available = mem->size - mem->pos;
if (size > available) {
size = available;
}
memcpy(mem->buffer, buf, sizeof(char) * size);
mem->pos += size;
return size;
}
int nextchfn(void *handler, const char ch ) {
size_t nextch;
fbuf_t *mem = handler;
nextch = (size_t) strchr((mem->buffer)+(mem->pos), ch);
if(nextch){
int numc = nextch-(int)(mem->buffer+mem->pos);
return numc;
}
else {
return 0; }
}
size_t seekfn(void *handler, fpos_t offset, int whence) {
size_t pos;
fbuf_t *mem = handler;
switch (whence) {
case SEEK_SET: pos = offset; break;
case SEEK_CUR: pos = mem->pos + offset; break;
case SEEK_END: pos = mem->size + offset; break;
default: return -1;
}
if (pos > mem->size) {
return -1;
}
mem->pos = pos;
return pos;
}
int closefn(void *handler) {
free(handler);
return 0;
}
fbuf_t *fbufopen(void *buf, size_t size, const char *mode) {
// This data is released on fclose.
fbuf_t* mem = (fbuf_t *) malloc(sizeof(fbuf_t));
// Zero-out the structure.
memset(mem, 0, sizeof(fbuf_t));
mem->size = size;
mem->buffer = buf;
return mem;
}