cyclone/mem-streams.c
2016-08-25 23:38:09 -04:00

91 lines
2.5 KiB
C

/**
* Cyclone Scheme
* https://github.com/justinethier/cyclone
*
* Copyright (c) 2014-2016, Justin Ethier
* All rights reserved.
*
* This file contains platform-specific code for memory streams.
*/
#include "cyclone/types.h"
#include "cyclone/runtime.h"
#include <errno.h>
//#include <limits.h>
//#include <ctype.h>
/* These macros are hardcoded here to support functions in this module. */
#define closcall1(td, clo, a1) \
if (type_is_pair_prim(clo)) { \
Cyc_apply(td, 0, (closure)(a1), clo); \
} else { \
((clo)->fn)(td, 1, clo, a1);\
}
#define return_closcall1(td, clo, a1) { \
char top; \
if (stack_overflow(&top, (((gc_thread_data *)data)->stack_limit))) { \
object buf[1]; buf[0] = a1;\
GC(td, clo, buf, 1); \
return; \
} else {\
closcall1(td, (closure) (clo), a1); \
return;\
} \
}
port_type Cyc_io_open_output_string(void *data)
{
make_port(p, NULL, 0);
errno = 0;
p.fp = open_memstream(&(p.mem_buf), &(p.mem_buf_len));
if (p.fp == NULL){
Cyc_rt_raise2(data, "Unable to open memory stream", obj_int2obj(errno));
}
return p;
}
void Cyc_io_get_output_string(void *data, object cont, object port)
{
Cyc_check_port(data, port);
if (((port_type *)port)->mem_buf == NULL) {
Cyc_rt_raise2(data, "Not an in-memory port", port);
}
{
port_type *p = (port_type *)port;
make_string_with_len(s, p->mem_buf, p->mem_buf_len);
return_closcall1(data, cont, &s);
}
}
// TODO: when closing a memory port, need to free mem_buf if != NULL
// Hacky approach to a minimal string buffer implementation. This may change in the future
// For background see: http://stackoverflow.com/questions/539537/memory-buffer-as-file
//port_type Cyc_io_open_output_string(void *data)
//
//// TODO: no, this is too hacky. fuck it, just use fmemopen or open_memstream
//// for non-supported platforms we'll raise an error and not do anything
//{
// FILE *f = fopen("/dev/null", "w");
// int i;
// int written = 0;
// char *buf = malloc(100000);
// make_port(p, NULL, 0); // TODO: probably wrong params, need to add buf to port obj and type
// //setbuffer(f, buf, 100000);
// if (0 != setvbuf (f, buf, _IOFBF, 100000)){
// // TODO: raise() instead?
// fprintf(stderr, "Unable to setvbuf!\n");
// exit(1);
// }
// for (i = 0; i < 1000; i++) {
// written += fprintf(f, "Number %d\n", i);
// }
// for (i = 0; i < written; i++) {
// printf("%c", buf[i]);
// }
// return p;
//}
//
//// END string buffers