Libav 0.7.1
libavformat/aviobuf.c
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00001 /*
00002  * Buffered I/O for ffmpeg system
00003  * Copyright (c) 2000,2001 Fabrice Bellard
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/crc.h"
00023 #include "libavutil/intreadwrite.h"
00024 #include "avformat.h"
00025 #include "avio.h"
00026 #include "avio_internal.h"
00027 #include "internal.h"
00028 #include "url.h"
00029 #include <stdarg.h>
00030 
00031 #define IO_BUFFER_SIZE 32768
00032 
00038 #define SHORT_SEEK_THRESHOLD 4096
00039 
00040 static void fill_buffer(AVIOContext *s);
00041 static int url_resetbuf(AVIOContext *s, int flags);
00042 
00043 int ffio_init_context(AVIOContext *s,
00044                   unsigned char *buffer,
00045                   int buffer_size,
00046                   int write_flag,
00047                   void *opaque,
00048                   int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
00049                   int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
00050                   int64_t (*seek)(void *opaque, int64_t offset, int whence))
00051 {
00052     s->buffer = buffer;
00053     s->buffer_size = buffer_size;
00054     s->buf_ptr = buffer;
00055     s->opaque = opaque;
00056     url_resetbuf(s, write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
00057     s->write_packet = write_packet;
00058     s->read_packet = read_packet;
00059     s->seek = seek;
00060     s->pos = 0;
00061     s->must_flush = 0;
00062     s->eof_reached = 0;
00063     s->error = 0;
00064 #if FF_API_OLD_AVIO
00065     s->is_streamed = 0;
00066 #endif
00067     s->seekable = AVIO_SEEKABLE_NORMAL;
00068     s->max_packet_size = 0;
00069     s->update_checksum= NULL;
00070     if(!read_packet && !write_flag){
00071         s->pos = buffer_size;
00072         s->buf_end = s->buffer + buffer_size;
00073     }
00074     s->read_pause = NULL;
00075     s->read_seek  = NULL;
00076     return 0;
00077 }
00078 
00079 #if FF_API_OLD_AVIO
00080 int init_put_byte(AVIOContext *s,
00081                   unsigned char *buffer,
00082                   int buffer_size,
00083                   int write_flag,
00084                   void *opaque,
00085                   int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
00086                   int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
00087                   int64_t (*seek)(void *opaque, int64_t offset, int whence))
00088 {
00089     return ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
00090                                 read_packet, write_packet, seek);
00091 }
00092 AVIOContext *av_alloc_put_byte(
00093                   unsigned char *buffer,
00094                   int buffer_size,
00095                   int write_flag,
00096                   void *opaque,
00097                   int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
00098                   int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
00099                   int64_t (*seek)(void *opaque, int64_t offset, int whence))
00100 {
00101     return avio_alloc_context(buffer, buffer_size, write_flag, opaque,
00102                               read_packet, write_packet, seek);
00103 }
00104 #endif
00105 
00106 AVIOContext *avio_alloc_context(
00107                   unsigned char *buffer,
00108                   int buffer_size,
00109                   int write_flag,
00110                   void *opaque,
00111                   int (*read_packet)(void *opaque, uint8_t *buf, int buf_size),
00112                   int (*write_packet)(void *opaque, uint8_t *buf, int buf_size),
00113                   int64_t (*seek)(void *opaque, int64_t offset, int whence))
00114 {
00115     AVIOContext *s = av_mallocz(sizeof(AVIOContext));
00116     if (!s)
00117         return NULL;
00118     ffio_init_context(s, buffer, buffer_size, write_flag, opaque,
00119                   read_packet, write_packet, seek);
00120     return s;
00121 }
00122 
00123 static void flush_buffer(AVIOContext *s)
00124 {
00125     if (s->buf_ptr > s->buffer) {
00126         if (s->write_packet && !s->error){
00127             int ret= s->write_packet(s->opaque, s->buffer, s->buf_ptr - s->buffer);
00128             if(ret < 0){
00129                 s->error = ret;
00130             }
00131         }
00132         if(s->update_checksum){
00133             s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
00134             s->checksum_ptr= s->buffer;
00135         }
00136         s->pos += s->buf_ptr - s->buffer;
00137     }
00138     s->buf_ptr = s->buffer;
00139 }
00140 
00141 void avio_w8(AVIOContext *s, int b)
00142 {
00143     *(s->buf_ptr)++ = b;
00144     if (s->buf_ptr >= s->buf_end)
00145         flush_buffer(s);
00146 }
00147 
00148 void ffio_fill(AVIOContext *s, int b, int count)
00149 {
00150     while (count > 0) {
00151         int len = FFMIN(s->buf_end - s->buf_ptr, count);
00152         memset(s->buf_ptr, b, len);
00153         s->buf_ptr += len;
00154 
00155         if (s->buf_ptr >= s->buf_end)
00156             flush_buffer(s);
00157 
00158         count -= len;
00159     }
00160 }
00161 
00162 void avio_write(AVIOContext *s, const unsigned char *buf, int size)
00163 {
00164     while (size > 0) {
00165         int len = FFMIN(s->buf_end - s->buf_ptr, size);
00166         memcpy(s->buf_ptr, buf, len);
00167         s->buf_ptr += len;
00168 
00169         if (s->buf_ptr >= s->buf_end)
00170             flush_buffer(s);
00171 
00172         buf += len;
00173         size -= len;
00174     }
00175 }
00176 
00177 void avio_flush(AVIOContext *s)
00178 {
00179     flush_buffer(s);
00180     s->must_flush = 0;
00181 }
00182 
00183 int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
00184 {
00185     int64_t offset1;
00186     int64_t pos;
00187     int force = whence & AVSEEK_FORCE;
00188     whence &= ~AVSEEK_FORCE;
00189 
00190     if(!s)
00191         return AVERROR(EINVAL);
00192 
00193     pos = s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer));
00194 
00195     if (whence != SEEK_CUR && whence != SEEK_SET)
00196         return AVERROR(EINVAL);
00197 
00198     if (whence == SEEK_CUR) {
00199         offset1 = pos + (s->buf_ptr - s->buffer);
00200         if (offset == 0)
00201             return offset1;
00202         offset += offset1;
00203     }
00204     offset1 = offset - pos;
00205     if (!s->must_flush &&
00206         offset1 >= 0 && offset1 <= (s->buf_end - s->buffer)) {
00207         /* can do the seek inside the buffer */
00208         s->buf_ptr = s->buffer + offset1;
00209     } else if ((!s->seekable ||
00210                offset1 <= s->buf_end + SHORT_SEEK_THRESHOLD - s->buffer) &&
00211                !s->write_flag && offset1 >= 0 &&
00212               (whence != SEEK_END || force)) {
00213         while(s->pos < offset && !s->eof_reached)
00214             fill_buffer(s);
00215         if (s->eof_reached)
00216             return AVERROR_EOF;
00217         s->buf_ptr = s->buf_end + offset - s->pos;
00218     } else {
00219         int64_t res;
00220 
00221 #if CONFIG_MUXERS || CONFIG_NETWORK
00222         if (s->write_flag) {
00223             flush_buffer(s);
00224             s->must_flush = 1;
00225         }
00226 #endif /* CONFIG_MUXERS || CONFIG_NETWORK */
00227         if (!s->seek)
00228             return AVERROR(EPIPE);
00229         if ((res = s->seek(s->opaque, offset, SEEK_SET)) < 0)
00230             return res;
00231         if (!s->write_flag)
00232             s->buf_end = s->buffer;
00233         s->buf_ptr = s->buffer;
00234         s->pos = offset;
00235     }
00236     s->eof_reached = 0;
00237     return offset;
00238 }
00239 
00240 #if FF_API_OLD_AVIO
00241 int url_fskip(AVIOContext *s, int64_t offset)
00242 {
00243     int64_t ret = avio_seek(s, offset, SEEK_CUR);
00244     return ret < 0 ? ret : 0;
00245 }
00246 
00247 int64_t url_ftell(AVIOContext *s)
00248 {
00249     return avio_seek(s, 0, SEEK_CUR);
00250 }
00251 #endif
00252 
00253 int64_t avio_size(AVIOContext *s)
00254 {
00255     int64_t size;
00256 
00257     if(!s)
00258         return AVERROR(EINVAL);
00259 
00260     if (!s->seek)
00261         return AVERROR(ENOSYS);
00262     size = s->seek(s->opaque, 0, AVSEEK_SIZE);
00263     if(size<0){
00264         if ((size = s->seek(s->opaque, -1, SEEK_END)) < 0)
00265             return size;
00266         size++;
00267         s->seek(s->opaque, s->pos, SEEK_SET);
00268     }
00269     return size;
00270 }
00271 
00272 #if FF_API_OLD_AVIO
00273 int url_feof(AVIOContext *s)
00274 {
00275     if(!s)
00276         return 0;
00277     return s->eof_reached;
00278 }
00279 
00280 int url_ferror(AVIOContext *s)
00281 {
00282     if(!s)
00283         return 0;
00284     return s->error;
00285 }
00286 #endif
00287 
00288 void avio_wl32(AVIOContext *s, unsigned int val)
00289 {
00290     avio_w8(s, val);
00291     avio_w8(s, val >> 8);
00292     avio_w8(s, val >> 16);
00293     avio_w8(s, val >> 24);
00294 }
00295 
00296 void avio_wb32(AVIOContext *s, unsigned int val)
00297 {
00298     avio_w8(s, val >> 24);
00299     avio_w8(s, val >> 16);
00300     avio_w8(s, val >> 8);
00301     avio_w8(s, val);
00302 }
00303 
00304 #if FF_API_OLD_AVIO
00305 void put_strz(AVIOContext *s, const char *str)
00306 {
00307     avio_put_str(s, str);
00308 }
00309 
00310 #define GET(name, type) \
00311     type get_be ##name(AVIOContext *s) \
00312 {\
00313     return avio_rb ##name(s);\
00314 }\
00315     type get_le ##name(AVIOContext *s) \
00316 {\
00317     return avio_rl ##name(s);\
00318 }
00319 
00320 GET(16, unsigned int)
00321 GET(24, unsigned int)
00322 GET(32, unsigned int)
00323 GET(64, uint64_t)
00324 
00325 #undef GET
00326 
00327 #define PUT(name, type ) \
00328     void put_le ##name(AVIOContext *s, type val)\
00329 {\
00330         avio_wl ##name(s, val);\
00331 }\
00332     void put_be ##name(AVIOContext *s, type val)\
00333 {\
00334         avio_wb ##name(s, val);\
00335 }
00336 
00337 PUT(16, unsigned int)
00338 PUT(24, unsigned int)
00339 PUT(32, unsigned int)
00340 PUT(64, uint64_t)
00341 #undef PUT
00342 
00343 int get_byte(AVIOContext *s)
00344 {
00345    return avio_r8(s);
00346 }
00347 int get_buffer(AVIOContext *s, unsigned char *buf, int size)
00348 {
00349     return avio_read(s, buf, size);
00350 }
00351 int get_partial_buffer(AVIOContext *s, unsigned char *buf, int size)
00352 {
00353     return ffio_read_partial(s, buf, size);
00354 }
00355 void put_byte(AVIOContext *s, int val)
00356 {
00357     avio_w8(s, val);
00358 }
00359 void put_buffer(AVIOContext *s, const unsigned char *buf, int size)
00360 {
00361     avio_write(s, buf, size);
00362 }
00363 void put_nbyte(AVIOContext *s, int b, int count)
00364 {
00365     ffio_fill(s, b, count);
00366 }
00367 
00368 int url_fopen(AVIOContext **s, const char *filename, int flags)
00369 {
00370     return avio_open(s, filename, flags);
00371 }
00372 int url_fclose(AVIOContext *s)
00373 {
00374     return avio_close(s);
00375 }
00376 int64_t url_fseek(AVIOContext *s, int64_t offset, int whence)
00377 {
00378     return avio_seek(s, offset, whence);
00379 }
00380 int64_t url_fsize(AVIOContext *s)
00381 {
00382     return avio_size(s);
00383 }
00384 int url_setbufsize(AVIOContext *s, int buf_size)
00385 {
00386     return ffio_set_buf_size(s, buf_size);
00387 }
00388 int url_fprintf(AVIOContext *s, const char *fmt, ...)
00389 {
00390     va_list ap;
00391     char buf[4096];
00392     int ret;
00393 
00394     va_start(ap, fmt);
00395     ret = vsnprintf(buf, sizeof(buf), fmt, ap);
00396     va_end(ap);
00397     avio_write(s, buf, strlen(buf));
00398     return ret;
00399 }
00400 void put_flush_packet(AVIOContext *s)
00401 {
00402     avio_flush(s);
00403 }
00404 int av_url_read_fpause(AVIOContext *s, int pause)
00405 {
00406     return avio_pause(s, pause);
00407 }
00408 int64_t av_url_read_fseek(AVIOContext *s, int stream_index,
00409                          int64_t timestamp, int flags)
00410 {
00411     return avio_seek_time(s, stream_index, timestamp, flags);
00412 }
00413 void init_checksum(AVIOContext *s,
00414                    unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
00415                    unsigned long checksum)
00416 {
00417     ffio_init_checksum(s, update_checksum, checksum);
00418 }
00419 unsigned long get_checksum(AVIOContext *s)
00420 {
00421     return ffio_get_checksum(s);
00422 }
00423 int url_open_dyn_buf(AVIOContext **s)
00424 {
00425     return avio_open_dyn_buf(s);
00426 }
00427 int url_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
00428 {
00429     return ffio_open_dyn_packet_buf(s, max_packet_size);
00430 }
00431 int url_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
00432 {
00433     return avio_close_dyn_buf(s, pbuffer);
00434 }
00435 int url_fdopen(AVIOContext **s, URLContext *h)
00436 {
00437     return ffio_fdopen(s, h);
00438 }
00439 #endif
00440 
00441 int avio_put_str(AVIOContext *s, const char *str)
00442 {
00443     int len = 1;
00444     if (str) {
00445         len += strlen(str);
00446         avio_write(s, (const unsigned char *) str, len);
00447     } else
00448         avio_w8(s, 0);
00449     return len;
00450 }
00451 
00452 int avio_put_str16le(AVIOContext *s, const char *str)
00453 {
00454     const uint8_t *q = str;
00455     int ret = 0;
00456 
00457     while (*q) {
00458         uint32_t ch;
00459         uint16_t tmp;
00460 
00461         GET_UTF8(ch, *q++, break;)
00462         PUT_UTF16(ch, tmp, avio_wl16(s, tmp);ret += 2;)
00463     }
00464     avio_wl16(s, 0);
00465     ret += 2;
00466     return ret;
00467 }
00468 
00469 int ff_get_v_length(uint64_t val){
00470     int i=1;
00471 
00472     while(val>>=7)
00473         i++;
00474 
00475     return i;
00476 }
00477 
00478 void ff_put_v(AVIOContext *bc, uint64_t val){
00479     int i= ff_get_v_length(val);
00480 
00481     while(--i>0)
00482         avio_w8(bc, 128 | (val>>(7*i)));
00483 
00484     avio_w8(bc, val&127);
00485 }
00486 
00487 void avio_wl64(AVIOContext *s, uint64_t val)
00488 {
00489     avio_wl32(s, (uint32_t)(val & 0xffffffff));
00490     avio_wl32(s, (uint32_t)(val >> 32));
00491 }
00492 
00493 void avio_wb64(AVIOContext *s, uint64_t val)
00494 {
00495     avio_wb32(s, (uint32_t)(val >> 32));
00496     avio_wb32(s, (uint32_t)(val & 0xffffffff));
00497 }
00498 
00499 void avio_wl16(AVIOContext *s, unsigned int val)
00500 {
00501     avio_w8(s, val);
00502     avio_w8(s, val >> 8);
00503 }
00504 
00505 void avio_wb16(AVIOContext *s, unsigned int val)
00506 {
00507     avio_w8(s, val >> 8);
00508     avio_w8(s, val);
00509 }
00510 
00511 void avio_wl24(AVIOContext *s, unsigned int val)
00512 {
00513     avio_wl16(s, val & 0xffff);
00514     avio_w8(s, val >> 16);
00515 }
00516 
00517 void avio_wb24(AVIOContext *s, unsigned int val)
00518 {
00519     avio_wb16(s, val >> 8);
00520     avio_w8(s, val);
00521 }
00522 
00523 #if FF_API_OLD_AVIO
00524 void put_tag(AVIOContext *s, const char *tag)
00525 {
00526     while (*tag) {
00527         avio_w8(s, *tag++);
00528     }
00529 }
00530 #endif
00531 
00532 /* Input stream */
00533 
00534 static void fill_buffer(AVIOContext *s)
00535 {
00536     uint8_t *dst= !s->max_packet_size && s->buf_end - s->buffer < s->buffer_size ? s->buf_end : s->buffer;
00537     int len= s->buffer_size - (dst - s->buffer);
00538     int max_buffer_size = s->max_packet_size ? s->max_packet_size : IO_BUFFER_SIZE;
00539 
00540     /* no need to do anything if EOF already reached */
00541     if (s->eof_reached)
00542         return;
00543 
00544     if(s->update_checksum && dst == s->buffer){
00545         if(s->buf_end > s->checksum_ptr)
00546             s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_end - s->checksum_ptr);
00547         s->checksum_ptr= s->buffer;
00548     }
00549 
00550     /* make buffer smaller in case it ended up large after probing */
00551     if (s->buffer_size > max_buffer_size) {
00552         ffio_set_buf_size(s, max_buffer_size);
00553 
00554         s->checksum_ptr = dst = s->buffer;
00555         len = s->buffer_size;
00556     }
00557 
00558     if(s->read_packet)
00559         len = s->read_packet(s->opaque, dst, len);
00560     else
00561         len = 0;
00562     if (len <= 0) {
00563         /* do not modify buffer if EOF reached so that a seek back can
00564            be done without rereading data */
00565         s->eof_reached = 1;
00566         if(len<0)
00567             s->error= len;
00568     } else {
00569         s->pos += len;
00570         s->buf_ptr = dst;
00571         s->buf_end = dst + len;
00572     }
00573 }
00574 
00575 unsigned long ff_crc04C11DB7_update(unsigned long checksum, const uint8_t *buf,
00576                                     unsigned int len)
00577 {
00578     return av_crc(av_crc_get_table(AV_CRC_32_IEEE), checksum, buf, len);
00579 }
00580 
00581 unsigned long ffio_get_checksum(AVIOContext *s)
00582 {
00583     s->checksum= s->update_checksum(s->checksum, s->checksum_ptr, s->buf_ptr - s->checksum_ptr);
00584     s->update_checksum= NULL;
00585     return s->checksum;
00586 }
00587 
00588 void ffio_init_checksum(AVIOContext *s,
00589                    unsigned long (*update_checksum)(unsigned long c, const uint8_t *p, unsigned int len),
00590                    unsigned long checksum)
00591 {
00592     s->update_checksum= update_checksum;
00593     if(s->update_checksum){
00594         s->checksum= checksum;
00595         s->checksum_ptr= s->buf_ptr;
00596     }
00597 }
00598 
00599 /* XXX: put an inline version */
00600 int avio_r8(AVIOContext *s)
00601 {
00602     if (s->buf_ptr >= s->buf_end)
00603         fill_buffer(s);
00604     if (s->buf_ptr < s->buf_end)
00605         return *s->buf_ptr++;
00606     return 0;
00607 }
00608 
00609 #if FF_API_OLD_AVIO
00610 int url_fgetc(AVIOContext *s)
00611 {
00612     if (s->buf_ptr >= s->buf_end)
00613         fill_buffer(s);
00614     if (s->buf_ptr < s->buf_end)
00615         return *s->buf_ptr++;
00616     return URL_EOF;
00617 }
00618 #endif
00619 
00620 int avio_read(AVIOContext *s, unsigned char *buf, int size)
00621 {
00622     int len, size1;
00623 
00624     size1 = size;
00625     while (size > 0) {
00626         len = s->buf_end - s->buf_ptr;
00627         if (len > size)
00628             len = size;
00629         if (len == 0) {
00630             if(size > s->buffer_size && !s->update_checksum){
00631                 if(s->read_packet)
00632                     len = s->read_packet(s->opaque, buf, size);
00633                 if (len <= 0) {
00634                     /* do not modify buffer if EOF reached so that a seek back can
00635                     be done without rereading data */
00636                     s->eof_reached = 1;
00637                     if(len<0)
00638                         s->error= len;
00639                     break;
00640                 } else {
00641                     s->pos += len;
00642                     size -= len;
00643                     buf += len;
00644                     s->buf_ptr = s->buffer;
00645                     s->buf_end = s->buffer/* + len*/;
00646                 }
00647             }else{
00648                 fill_buffer(s);
00649                 len = s->buf_end - s->buf_ptr;
00650                 if (len == 0)
00651                     break;
00652             }
00653         } else {
00654             memcpy(buf, s->buf_ptr, len);
00655             buf += len;
00656             s->buf_ptr += len;
00657             size -= len;
00658         }
00659     }
00660     if (size1 == size) {
00661         if (s->error)         return s->error;
00662         if (s->eof_reached)   return AVERROR_EOF;
00663     }
00664     return size1 - size;
00665 }
00666 
00667 int ffio_read_partial(AVIOContext *s, unsigned char *buf, int size)
00668 {
00669     int len;
00670 
00671     if(size<0)
00672         return -1;
00673 
00674     len = s->buf_end - s->buf_ptr;
00675     if (len == 0) {
00676         fill_buffer(s);
00677         len = s->buf_end - s->buf_ptr;
00678     }
00679     if (len > size)
00680         len = size;
00681     memcpy(buf, s->buf_ptr, len);
00682     s->buf_ptr += len;
00683     if (!len) {
00684         if (s->error)         return s->error;
00685         if (s->eof_reached)   return AVERROR_EOF;
00686     }
00687     return len;
00688 }
00689 
00690 unsigned int avio_rl16(AVIOContext *s)
00691 {
00692     unsigned int val;
00693     val = avio_r8(s);
00694     val |= avio_r8(s) << 8;
00695     return val;
00696 }
00697 
00698 unsigned int avio_rl24(AVIOContext *s)
00699 {
00700     unsigned int val;
00701     val = avio_rl16(s);
00702     val |= avio_r8(s) << 16;
00703     return val;
00704 }
00705 
00706 unsigned int avio_rl32(AVIOContext *s)
00707 {
00708     unsigned int val;
00709     val = avio_rl16(s);
00710     val |= avio_rl16(s) << 16;
00711     return val;
00712 }
00713 
00714 uint64_t avio_rl64(AVIOContext *s)
00715 {
00716     uint64_t val;
00717     val = (uint64_t)avio_rl32(s);
00718     val |= (uint64_t)avio_rl32(s) << 32;
00719     return val;
00720 }
00721 
00722 unsigned int avio_rb16(AVIOContext *s)
00723 {
00724     unsigned int val;
00725     val = avio_r8(s) << 8;
00726     val |= avio_r8(s);
00727     return val;
00728 }
00729 
00730 unsigned int avio_rb24(AVIOContext *s)
00731 {
00732     unsigned int val;
00733     val = avio_rb16(s) << 8;
00734     val |= avio_r8(s);
00735     return val;
00736 }
00737 unsigned int avio_rb32(AVIOContext *s)
00738 {
00739     unsigned int val;
00740     val = avio_rb16(s) << 16;
00741     val |= avio_rb16(s);
00742     return val;
00743 }
00744 
00745 #if FF_API_OLD_AVIO
00746 char *get_strz(AVIOContext *s, char *buf, int maxlen)
00747 {
00748     avio_get_str(s, INT_MAX, buf, maxlen);
00749     return buf;
00750 }
00751 #endif
00752 
00753 int ff_get_line(AVIOContext *s, char *buf, int maxlen)
00754 {
00755     int i = 0;
00756     char c;
00757 
00758     do {
00759         c = avio_r8(s);
00760         if (c && i < maxlen-1)
00761             buf[i++] = c;
00762     } while (c != '\n' && c);
00763 
00764     buf[i] = 0;
00765     return i;
00766 }
00767 
00768 int avio_get_str(AVIOContext *s, int maxlen, char *buf, int buflen)
00769 {
00770     int i;
00771 
00772     // reserve 1 byte for terminating 0
00773     buflen = FFMIN(buflen - 1, maxlen);
00774     for (i = 0; i < buflen; i++)
00775         if (!(buf[i] = avio_r8(s)))
00776             return i + 1;
00777     if (buflen)
00778         buf[i] = 0;
00779     for (; i < maxlen; i++)
00780         if (!avio_r8(s))
00781             return i + 1;
00782     return maxlen;
00783 }
00784 
00785 #define GET_STR16(type, read) \
00786     int avio_get_str16 ##type(AVIOContext *pb, int maxlen, char *buf, int buflen)\
00787 {\
00788     char* q = buf;\
00789     int ret = 0;\
00790     while (ret + 1 < maxlen) {\
00791         uint8_t tmp;\
00792         uint32_t ch;\
00793         GET_UTF16(ch, (ret += 2) <= maxlen ? read(pb) : 0, break;)\
00794         if (!ch)\
00795             break;\
00796         PUT_UTF8(ch, tmp, if (q - buf < buflen - 1) *q++ = tmp;)\
00797     }\
00798     *q = 0;\
00799     return ret;\
00800 }\
00801 
00802 GET_STR16(le, avio_rl16)
00803 GET_STR16(be, avio_rb16)
00804 
00805 #undef GET_STR16
00806 
00807 uint64_t avio_rb64(AVIOContext *s)
00808 {
00809     uint64_t val;
00810     val = (uint64_t)avio_rb32(s) << 32;
00811     val |= (uint64_t)avio_rb32(s);
00812     return val;
00813 }
00814 
00815 uint64_t ffio_read_varlen(AVIOContext *bc){
00816     uint64_t val = 0;
00817     int tmp;
00818 
00819     do{
00820         tmp = avio_r8(bc);
00821         val= (val<<7) + (tmp&127);
00822     }while(tmp&128);
00823     return val;
00824 }
00825 
00826 int ffio_fdopen(AVIOContext **s, URLContext *h)
00827 {
00828     uint8_t *buffer;
00829     int buffer_size, max_packet_size;
00830 
00831     max_packet_size = h->max_packet_size;
00832     if (max_packet_size) {
00833         buffer_size = max_packet_size; /* no need to bufferize more than one packet */
00834     } else {
00835         buffer_size = IO_BUFFER_SIZE;
00836     }
00837     buffer = av_malloc(buffer_size);
00838     if (!buffer)
00839         return AVERROR(ENOMEM);
00840 
00841     *s = av_mallocz(sizeof(AVIOContext));
00842     if(!*s) {
00843         av_free(buffer);
00844         return AVERROR(ENOMEM);
00845     }
00846 
00847     if (ffio_init_context(*s, buffer, buffer_size,
00848                       h->flags & AVIO_FLAG_WRITE, h,
00849                       ffurl_read, ffurl_write, ffurl_seek) < 0) {
00850         av_free(buffer);
00851         av_freep(s);
00852         return AVERROR(EIO);
00853     }
00854 #if FF_API_OLD_AVIO
00855     (*s)->is_streamed = h->is_streamed;
00856 #endif
00857     (*s)->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
00858     (*s)->max_packet_size = max_packet_size;
00859     if(h->prot) {
00860         (*s)->read_pause = (int (*)(void *, int))h->prot->url_read_pause;
00861         (*s)->read_seek  = (int64_t (*)(void *, int, int64_t, int))h->prot->url_read_seek;
00862     }
00863     return 0;
00864 }
00865 
00866 int ffio_set_buf_size(AVIOContext *s, int buf_size)
00867 {
00868     uint8_t *buffer;
00869     buffer = av_malloc(buf_size);
00870     if (!buffer)
00871         return AVERROR(ENOMEM);
00872 
00873     av_free(s->buffer);
00874     s->buffer = buffer;
00875     s->buffer_size = buf_size;
00876     s->buf_ptr = buffer;
00877     url_resetbuf(s, s->write_flag ? AVIO_FLAG_WRITE : AVIO_FLAG_READ);
00878     return 0;
00879 }
00880 
00881 static int url_resetbuf(AVIOContext *s, int flags)
00882 {
00883     assert(flags == AVIO_FLAG_WRITE || flags == AVIO_FLAG_READ);
00884 
00885     if (flags & AVIO_FLAG_WRITE) {
00886         s->buf_end = s->buffer + s->buffer_size;
00887         s->write_flag = 1;
00888     } else {
00889         s->buf_end = s->buffer;
00890         s->write_flag = 0;
00891     }
00892     return 0;
00893 }
00894 
00895 int ffio_rewind_with_probe_data(AVIOContext *s, unsigned char *buf, int buf_size)
00896 {
00897     int64_t buffer_start;
00898     int buffer_size;
00899     int overlap, new_size, alloc_size;
00900 
00901     if (s->write_flag)
00902         return AVERROR(EINVAL);
00903 
00904     buffer_size = s->buf_end - s->buffer;
00905 
00906     /* the buffers must touch or overlap */
00907     if ((buffer_start = s->pos - buffer_size) > buf_size)
00908         return AVERROR(EINVAL);
00909 
00910     overlap = buf_size - buffer_start;
00911     new_size = buf_size + buffer_size - overlap;
00912 
00913     alloc_size = FFMAX(s->buffer_size, new_size);
00914     if (alloc_size > buf_size)
00915         if (!(buf = av_realloc(buf, alloc_size)))
00916             return AVERROR(ENOMEM);
00917 
00918     if (new_size > buf_size) {
00919         memcpy(buf + buf_size, s->buffer + overlap, buffer_size - overlap);
00920         buf_size = new_size;
00921     }
00922 
00923     av_free(s->buffer);
00924     s->buf_ptr = s->buffer = buf;
00925     s->buffer_size = alloc_size;
00926     s->pos = buf_size;
00927     s->buf_end = s->buf_ptr + buf_size;
00928     s->eof_reached = 0;
00929     s->must_flush = 0;
00930 
00931     return 0;
00932 }
00933 
00934 int avio_open(AVIOContext **s, const char *filename, int flags)
00935 {
00936     URLContext *h;
00937     int err;
00938 
00939     err = ffurl_open(&h, filename, flags);
00940     if (err < 0)
00941         return err;
00942     err = ffio_fdopen(s, h);
00943     if (err < 0) {
00944         ffurl_close(h);
00945         return err;
00946     }
00947     return 0;
00948 }
00949 
00950 int avio_close(AVIOContext *s)
00951 {
00952     URLContext *h = s->opaque;
00953 
00954     av_free(s->buffer);
00955     av_free(s);
00956     return ffurl_close(h);
00957 }
00958 
00959 #if FF_API_OLD_AVIO
00960 URLContext *url_fileno(AVIOContext *s)
00961 {
00962     return s->opaque;
00963 }
00964 #endif
00965 
00966 int avio_printf(AVIOContext *s, const char *fmt, ...)
00967 {
00968     va_list ap;
00969     char buf[4096];
00970     int ret;
00971 
00972     va_start(ap, fmt);
00973     ret = vsnprintf(buf, sizeof(buf), fmt, ap);
00974     va_end(ap);
00975     avio_write(s, buf, strlen(buf));
00976     return ret;
00977 }
00978 
00979 #if FF_API_OLD_AVIO
00980 char *url_fgets(AVIOContext *s, char *buf, int buf_size)
00981 {
00982     int c;
00983     char *q;
00984 
00985     c = avio_r8(s);
00986     if (s->eof_reached)
00987         return NULL;
00988     q = buf;
00989     for(;;) {
00990         if (s->eof_reached || c == '\n')
00991             break;
00992         if ((q - buf) < buf_size - 1)
00993             *q++ = c;
00994         c = avio_r8(s);
00995     }
00996     if (buf_size > 0)
00997         *q = '\0';
00998     return buf;
00999 }
01000 
01001 int url_fget_max_packet_size(AVIOContext *s)
01002 {
01003     return s->max_packet_size;
01004 }
01005 #endif
01006 
01007 int avio_pause(AVIOContext *s, int pause)
01008 {
01009     if (!s->read_pause)
01010         return AVERROR(ENOSYS);
01011     return s->read_pause(s->opaque, pause);
01012 }
01013 
01014 int64_t avio_seek_time(AVIOContext *s, int stream_index,
01015                        int64_t timestamp, int flags)
01016 {
01017     URLContext *h = s->opaque;
01018     int64_t ret;
01019     if (!s->read_seek)
01020         return AVERROR(ENOSYS);
01021     ret = s->read_seek(h, stream_index, timestamp, flags);
01022     if(ret >= 0) {
01023         int64_t pos;
01024         s->buf_ptr = s->buf_end; // Flush buffer
01025         pos = s->seek(h, 0, SEEK_CUR);
01026         if (pos >= 0)
01027             s->pos = pos;
01028         else if (pos != AVERROR(ENOSYS))
01029             ret = pos;
01030     }
01031     return ret;
01032 }
01033 
01034 /* buffer handling */
01035 #if FF_API_OLD_AVIO
01036 int url_open_buf(AVIOContext **s, uint8_t *buf, int buf_size, int flags)
01037 {
01038     int ret;
01039     *s = av_mallocz(sizeof(AVIOContext));
01040     if(!*s)
01041         return AVERROR(ENOMEM);
01042     ret = ffio_init_context(*s, buf, buf_size,
01043                             flags & AVIO_FLAG_WRITE,
01044                         NULL, NULL, NULL, NULL);
01045     if(ret != 0)
01046         av_freep(s);
01047     return ret;
01048 }
01049 
01050 int url_close_buf(AVIOContext *s)
01051 {
01052     avio_flush(s);
01053     return s->buf_ptr - s->buffer;
01054 }
01055 #endif
01056 
01057 /* output in a dynamic buffer */
01058 
01059 typedef struct DynBuffer {
01060     int pos, size, allocated_size;
01061     uint8_t *buffer;
01062     int io_buffer_size;
01063     uint8_t io_buffer[1];
01064 } DynBuffer;
01065 
01066 static int dyn_buf_write(void *opaque, uint8_t *buf, int buf_size)
01067 {
01068     DynBuffer *d = opaque;
01069     unsigned new_size, new_allocated_size;
01070 
01071     /* reallocate buffer if needed */
01072     new_size = d->pos + buf_size;
01073     new_allocated_size = d->allocated_size;
01074     if(new_size < d->pos || new_size > INT_MAX/2)
01075         return -1;
01076     while (new_size > new_allocated_size) {
01077         if (!new_allocated_size)
01078             new_allocated_size = new_size;
01079         else
01080             new_allocated_size += new_allocated_size / 2 + 1;
01081     }
01082 
01083     if (new_allocated_size > d->allocated_size) {
01084         d->buffer = av_realloc(d->buffer, new_allocated_size);
01085         if(d->buffer == NULL)
01086              return AVERROR(ENOMEM);
01087         d->allocated_size = new_allocated_size;
01088     }
01089     memcpy(d->buffer + d->pos, buf, buf_size);
01090     d->pos = new_size;
01091     if (d->pos > d->size)
01092         d->size = d->pos;
01093     return buf_size;
01094 }
01095 
01096 static int dyn_packet_buf_write(void *opaque, uint8_t *buf, int buf_size)
01097 {
01098     unsigned char buf1[4];
01099     int ret;
01100 
01101     /* packetized write: output the header */
01102     AV_WB32(buf1, buf_size);
01103     ret= dyn_buf_write(opaque, buf1, 4);
01104     if(ret < 0)
01105         return ret;
01106 
01107     /* then the data */
01108     return dyn_buf_write(opaque, buf, buf_size);
01109 }
01110 
01111 static int64_t dyn_buf_seek(void *opaque, int64_t offset, int whence)
01112 {
01113     DynBuffer *d = opaque;
01114 
01115     if (whence == SEEK_CUR)
01116         offset += d->pos;
01117     else if (whence == SEEK_END)
01118         offset += d->size;
01119     if (offset < 0 || offset > 0x7fffffffLL)
01120         return -1;
01121     d->pos = offset;
01122     return 0;
01123 }
01124 
01125 static int url_open_dyn_buf_internal(AVIOContext **s, int max_packet_size)
01126 {
01127     DynBuffer *d;
01128     unsigned io_buffer_size = max_packet_size ? max_packet_size : 1024;
01129 
01130     if(sizeof(DynBuffer) + io_buffer_size < io_buffer_size)
01131         return -1;
01132     d = av_mallocz(sizeof(DynBuffer) + io_buffer_size);
01133     if (!d)
01134         return AVERROR(ENOMEM);
01135     d->io_buffer_size = io_buffer_size;
01136     *s = avio_alloc_context(d->io_buffer, d->io_buffer_size, 1, d, NULL,
01137                             max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
01138                             max_packet_size ? NULL : dyn_buf_seek);
01139     if(!*s) {
01140         av_free(d);
01141         return AVERROR(ENOMEM);
01142     }
01143     (*s)->max_packet_size = max_packet_size;
01144     return 0;
01145 }
01146 
01147 int avio_open_dyn_buf(AVIOContext **s)
01148 {
01149     return url_open_dyn_buf_internal(s, 0);
01150 }
01151 
01152 int ffio_open_dyn_packet_buf(AVIOContext **s, int max_packet_size)
01153 {
01154     if (max_packet_size <= 0)
01155         return -1;
01156     return url_open_dyn_buf_internal(s, max_packet_size);
01157 }
01158 
01159 int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer)
01160 {
01161     DynBuffer *d = s->opaque;
01162     int size;
01163     static const char padbuf[FF_INPUT_BUFFER_PADDING_SIZE] = {0};
01164     int padding = 0;
01165 
01166     /* don't attempt to pad fixed-size packet buffers */
01167     if (!s->max_packet_size) {
01168         avio_write(s, padbuf, sizeof(padbuf));
01169         padding = FF_INPUT_BUFFER_PADDING_SIZE;
01170     }
01171 
01172     avio_flush(s);
01173 
01174     *pbuffer = d->buffer;
01175     size = d->size;
01176     av_free(d);
01177     av_free(s);
01178     return size - padding;
01179 }