micropython/py/reader.c

147 lines
4.2 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013-2016 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include <assert.h>
#include "py/mperrno.h"
#include "py/reader.h"
typedef struct _mp_reader_mem_t {
size_t free_len; // if >0 mem is freed on close by: m_free(beg, free_len)
const byte *beg;
const byte *cur;
const byte *end;
} mp_reader_mem_t;
STATIC mp_uint_t mp_reader_mem_readbyte(void *data) {
mp_reader_mem_t *reader = (mp_reader_mem_t*)data;
if (reader->cur < reader->end) {
return *reader->cur++;
} else {
return MP_READER_EOF;
}
}
STATIC void mp_reader_mem_close(void *data) {
mp_reader_mem_t *reader = (mp_reader_mem_t*)data;
if (reader->free_len > 0) {
m_del(char, (char*)reader->beg, reader->free_len);
}
m_del_obj(mp_reader_mem_t, reader);
}
bool mp_reader_new_mem(mp_reader_t *reader, const byte *buf, size_t len, size_t free_len) {
mp_reader_mem_t *rm = m_new_obj_maybe(mp_reader_mem_t);
if (rm == NULL) {
return false;
}
rm->free_len = free_len;
rm->beg = buf;
rm->cur = buf;
rm->end = buf + len;
reader->data = rm;
reader->readbyte = mp_reader_mem_readbyte;
reader->close = mp_reader_mem_close;
return true;
}
#if MICROPY_READER_POSIX
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
typedef struct _mp_reader_posix_t {
bool close_fd;
int fd;
size_t len;
size_t pos;
byte buf[20];
} mp_reader_posix_t;
STATIC mp_uint_t mp_reader_posix_readbyte(void *data) {
mp_reader_posix_t *reader = (mp_reader_posix_t*)data;
if (reader->pos >= reader->len) {
if (reader->len == 0) {
return MP_READER_EOF;
} else {
int n = read(reader->fd, reader->buf, sizeof(reader->buf));
if (n <= 0) {
reader->len = 0;
return MP_READER_EOF;
}
reader->len = n;
reader->pos = 0;
}
}
return reader->buf[reader->pos++];
}
STATIC void mp_reader_posix_close(void *data) {
mp_reader_posix_t *reader = (mp_reader_posix_t*)data;
if (reader->close_fd) {
close(reader->fd);
}
m_del_obj(mp_reader_posix_t, reader);
}
int mp_reader_new_file_from_fd(mp_reader_t *reader, int fd, bool close_fd) {
mp_reader_posix_t *rp = m_new_obj_maybe(mp_reader_posix_t);
if (rp == NULL) {
if (close_fd) {
close(fd);
}
return MP_ENOMEM;
}
rp->close_fd = close_fd;
rp->fd = fd;
int n = read(rp->fd, rp->buf, sizeof(rp->buf));
if (n == -1) {
if (close_fd) {
close(fd);
}
return errno;
}
rp->len = n;
rp->pos = 0;
reader->data = rp;
reader->readbyte = mp_reader_posix_readbyte;
reader->close = mp_reader_posix_close;
return 0; // success
}
int mp_reader_new_file(mp_reader_t *reader, const char *filename) {
int fd = open(filename, O_RDONLY, 0644);
if (fd < 0) {
return errno;
}
return mp_reader_new_file_from_fd(reader, fd, true);
}
#endif