/* * Buffered I/O for ffmpeg system * Copyright (c) 2000,2001 Fabrice Bellard * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */#include "avformat.h"#include "avio.h"#include <stdarg.h>#define IO_BUFFER_SIZE 32768int init_put_byte(ByteIOContext *s,                  unsigned char *buffer,                  int buffer_size,                  int write_flag,                  void *opaque,                  int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),                  void (*write_packet)(void *opaque, uint8_t *buf, int buf_size),                  int (*seek)(void *opaque, offset_t offset, int whence)){    s->buffer = buffer;    s->buffer_size = buffer_size;    s->buf_ptr = buffer;    s->write_flag = write_flag;    if (!s->write_flag)         s->buf_end = buffer;    else        s->buf_end = buffer + buffer_size;    s->opaque = opaque;    s->write_packet = write_packet;    s->read_packet = read_packet;    s->seek = seek;    s->pos = 0;    s->must_flush = 0;    s->eof_reached = 0;    s->is_streamed = 0;    s->max_packet_size = 0;    s->update_checksum= NULL;    return 0;}                  #ifdef CONFIG_ENCODERSstatic void flush_buffer(ByteIOContext *s){    if (s->buf_ptr > s->buffer) {        if (s->write_packet)            s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);        if(s->update_checksum){            s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);            s->checksum_ptr= s->buffer;        }        s->pos += s->buf_ptr - s->buffer;    }    s->buf_ptr = s->buffer;}void put_byte(ByteIOContext *s, int b){    *(s->buf_ptr)++ = b;    if (s->buf_ptr >= s->buf_end)         flush_buffer(s);}void put_buffer(ByteIOContext *s, const unsigned char *buf, int size){    int len;    while (size > 0) {        len = (s->buf_end - s->buf_ptr);        if (len > size)            len = size;        memcpy(s->buf_ptr, buf, len);        s->buf_ptr += len;        if (s->buf_ptr >= s->buf_end)             flush_buffer(s);        buf += len;        size -= len;    }}void put_flush_packet(ByteIOContext *s){    flush_buffer(s);    s->must_flush = 0;}#endif //CONFIG_ENCODERSoffset_t url_fseek(ByteIOContext *s, offset_t offset, int whence){    offset_t offset1;    if (whence != SEEK_CUR && whence != SEEK_SET)        return -EINVAL;    #ifdef CONFIG_ENCODERS    if (s->write_flag) {        if (whence == SEEK_CUR) {            offset1 = s->pos + (s->buf_ptr - s->buffer);            if (offset == 0)                return offset1;            offset += offset1;        }        offset1 = offset - s->pos;        if (!s->must_flush &&             offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) {            /* can do the seek inside the buffer */            s->buf_ptr = s->buffer + offset1;        } else {            if (!s->seek)                return -EPIPE;            flush_buffer(s);            s->must_flush = 1;            s->buf_ptr = s->buffer;            s->seek(s->opaque, offset, SEEK_SET);            s->pos = offset;        }    } else #endif //CONFIG_ENCODERS    {        if (whence == SEEK_CUR) {            offset1 = s->pos - (s->buf_end - s->buffer) + (s->buf_ptr - s->buffer);            if (offset == 0)                return offset1;            offset += offset1;        }        offset1 = offset - (s->pos - (s->buf_end - s->buffer));        if (offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {            /* can do the seek inside the buffer */            s->buf_ptr = s->buffer + offset1;        } else {            if (!s->seek)                return -EPIPE;            s->buf_ptr = s->buffer;            s->buf_end = s->buffer;            s->seek(s->opaque, offset, SEEK_SET);            s->pos = offset;        }        s->eof_reached = 0;    }    return offset;}void url_fskip(ByteIOContext *s, offset_t offset){    url_fseek(s, offset, SEEK_CUR);}offset_t url_ftell(ByteIOContext *s){    return url_fseek(s, 0, SEEK_CUR);}int url_feof(ByteIOContext *s){    return s->eof_reached;}#ifdef CONFIG_ENCODERSvoid put_le32(ByteIOContext *s, unsigned int val){    put_byte(s, val);    put_byte(s, val >> 8);    put_byte(s, val >> 16);    put_byte(s, val >> 24);}void put_be32(ByteIOContext *s, unsigned int val){    put_byte(s, val >> 24);    put_byte(s, val >> 16);    put_byte(s, val >> 8);    put_byte(s, val);}/* IEEE format is assumed */void put_be64_double(ByteIOContext *s, double val){    union {        double d;        uint64_t ull;    } u;    u.d = val;    put_be64(s, u.ull);}void put_strz(ByteIOContext *s, const char *str){    if (str)        put_buffer(s, (const unsigned char *) str, strlen(str) + 1);    else        put_byte(s, 0);}void put_le64(ByteIOContext *s, uint64_t val){    put_le32(s, (uint32_t)(val & 0xffffffff));    put_le32(s, (uint32_t)(val >> 32));}void put_be64(ByteIOContext *s, uint64_t val){    put_be32(s, (uint32_t)(val >> 32));    put_be32(s, (uint32_t)(val & 0xffffffff));}void put_le16(ByteIOContext *s, unsigned int val){    put_byte(s, val);    put_byte(s, val >> 8);}void put_be16(ByteIOContext *s, unsigned int val){    put_byte(s, val >> 8);    put_byte(s, val);}void put_tag(ByteIOContext *s, const char *tag){    while (*tag) {        put_byte(s, *tag++);    }}#endif //CONFIG_ENCODERS/* Input stream */static void fill_buffer(ByteIOContext *s){    int len;    /* no need to do anything if EOF already reached */    if (s->eof_reached)        return;    if(s->update_checksum){        s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);        s->checksum_ptr= s->buffer;    }    len = s->read_packet(s->opaque, s->buffer, s->buffer_size);    if (len <= 0) {        /* do not modify buffer if EOF reached so that a seek back can           be done without rereading data */        s->eof_reached = 1;    } else {        s->pos += len;        s->buf_ptr = s->buffer;        s->buf_end = s->buffer + len;    }}unsigned long get_checksum(ByteIOContext *s){    s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);    s->update_checksum= NULL;    return s->checksum;}void init_checksum(ByteIOContext *s, unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len), unsigned long checksum){    s->update_checksum= update_checksum;    if(s->update_checksum){        s->checksum= s->update_checksum(checksum, NULL, 0);        s->checksum_ptr= s->buf_ptr;    }}/* NOTE: return 0 if EOF, so you cannot use it if EOF handling is   necessary *//* XXX: put an inline version */int get_byte(ByteIOContext *s){    if (s->buf_ptr < s->buf_end) {        return *s->buf_ptr++;    } else {        fill_buffer(s);        if (s->buf_ptr < s->buf_end)            return *s->buf_ptr++;        else            return 0;    }}/* NOTE: return URL_EOF (-1) if EOF */int url_fgetc(ByteIOContext *s){    if (s->buf_ptr < s->buf_end) {        return *s->buf_ptr++;    } else {        fill_buffer(s);        if (s->buf_ptr < s->buf_end)            return *s->buf_ptr++;        else            return URL_EOF;    }}int get_buffer(ByteIOContext *s, unsigned char *buf, int size){    int len, size1;    size1 = size;    while (size > 0) {        len = s->buf_end - s->buf_ptr;        if (len > size)            len = size;        if (len == 0) {            fill_buffer(s);            len = s->buf_end - s->buf_ptr;            if (len == 0)                break;        } else {            memcpy(buf, s->buf_ptr, len);            buf += len;            s->buf_ptr += len;            size -= len;        }    }    return size1 - size;}int get_partial_buffer(ByteIOContext *s, unsigned char *buf, int size){    int len;    len = s->buf_end - s->buf_ptr;    if (len == 0) {        fill_buffer(s);        len = s->buf_end - s->buf_ptr;    }    if (len > size)        len = size;    memcpy(buf, s->buf_ptr, len);    s->buf_ptr += len;    return len;}unsigned int get_le16(ByteIOContext *s){    unsigned int val;    val = get_byte(s);    val |= get_byte(s) << 8;    return val;}unsigned int get_le32(ByteIOContext *s){    unsigned int val;    val = get_byte(s);    val |= get_byte(s) << 8;    val |= get_byte(s) << 16;    val |= get_byte(s) << 24;    return val;}uint64_t get_le64(ByteIOContext *s)