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-rw-r--r--libavformat/aviobuf.c687
1 files changed, 687 insertions, 0 deletions
diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c
new file mode 100644
index 0000000000..2e931bd849
--- /dev/null
+++ b/libavformat/aviobuf.c
@@ -0,0 +1,687 @@
+/*
+ * 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 <stdarg.h>
+
+#define IO_BUFFER_SIZE 32768
+
+int init_put_byte(ByteIOContext *s,
+ unsigned char *buffer,
+ int buffer_size,
+ int write_flag,
+ void *opaque,
+ int (*read_packet)(void *opaque, UINT8 *buf, int buf_size),
+ void (*write_packet)(void *opaque, UINT8 *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;
+ return 0;
+}
+
+
+static 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);
+ 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;
+}
+
+offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence)
+{
+ offset_t offset1;
+
+ if (whence != SEEK_CUR && whence != SEEK_SET)
+ return -EINVAL;
+
+ 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 {
+ 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;
+}
+
+void 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 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 val)
+{
+ put_le32(s, (UINT32)(val & 0xffffffff));
+ put_le32(s, (UINT32)(val >> 32));
+}
+
+void put_be64(ByteIOContext *s, UINT64 val)
+{
+ put_be32(s, (UINT32)(val >> 32));
+ put_be32(s, (UINT32)(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++);
+ }
+}
+
+/* Input stream */
+
+static void fill_buffer(ByteIOContext *s)
+{
+ int len;
+
+ /* no need to do anything if EOF already reached */
+ if (s->eof_reached)
+ return;
+ 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;
+ }
+}
+
+/* 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;
+}
+
+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 get_le64(ByteIOContext *s)
+{
+ UINT64 val;
+ val = (UINT64)get_le32(s);
+ val |= (UINT64)get_le32(s) << 32;
+ return val;
+}
+
+unsigned int get_be16(ByteIOContext *s)
+{
+ unsigned int val;
+ val = get_byte(s) << 8;
+ val |= get_byte(s);
+ return val;
+}
+
+unsigned int get_be32(ByteIOContext *s)
+{
+ unsigned int val;
+ val = get_byte(s) << 24;
+ val |= get_byte(s) << 16;
+ val |= get_byte(s) << 8;
+ val |= get_byte(s);
+ return val;
+}
+
+double get_be64_double(ByteIOContext *s)
+{
+ union {
+ double d;
+ UINT64 ull;
+ } u;
+
+ u.ull = get_be64(s);
+ return u.d;
+}
+
+char *get_strz(ByteIOContext *s, char *buf, int maxlen)
+{
+ int i = 0;
+ char c;
+
+ while ((c = get_byte(s))) {
+ if (i < maxlen-1)
+ buf[i++] = c;
+ }
+
+ buf[i] = 0; /* Ensure null terminated, but may be truncated */
+
+ return buf;
+}
+
+UINT64 get_be64(ByteIOContext *s)
+{
+ UINT64 val;
+ val = (UINT64)get_be32(s) << 32;
+ val |= (UINT64)get_be32(s);
+ return val;
+}
+
+/* link with avio functions */
+
+void url_write_packet(void *opaque, UINT8 *buf, int buf_size)
+{
+ URLContext *h = opaque;
+ url_write(h, buf, buf_size);
+}
+
+int url_read_packet(void *opaque, UINT8 *buf, int buf_size)
+{
+ URLContext *h = opaque;
+ return url_read(h, buf, buf_size);
+}
+
+int url_seek_packet(void *opaque, INT64 offset, int whence)
+{
+ URLContext *h = opaque;
+ url_seek(h, offset, whence);
+ return 0;
+}
+
+int url_fdopen(ByteIOContext *s, URLContext *h)
+{
+ UINT8 *buffer;
+ int buffer_size, max_packet_size;
+
+
+ max_packet_size = url_get_max_packet_size(h);
+ if (max_packet_size) {
+ buffer_size = max_packet_size; /* no need to bufferize more than one packet */
+ } else {
+ buffer_size = IO_BUFFER_SIZE;
+ }
+ buffer = av_malloc(buffer_size);
+ if (!buffer)
+ return -ENOMEM;
+
+ if (init_put_byte(s, buffer, buffer_size,
+ (h->flags & URL_WRONLY) != 0, h,
+ url_read_packet, url_write_packet, url_seek_packet) < 0) {
+ av_free(buffer);
+ return -EIO;
+ }
+ s->is_streamed = h->is_streamed;
+ s->max_packet_size = max_packet_size;
+ return 0;
+}
+
+/* XXX: must be called before any I/O */
+int url_setbufsize(ByteIOContext *s, int buf_size)
+{
+ UINT8 *buffer;
+ buffer = av_malloc(buf_size);
+ if (!buffer)
+ return -ENOMEM;
+
+ av_free(s->buffer);
+ s->buffer = buffer;
+ s->buffer_size = buf_size;
+ s->buf_ptr = buffer;
+ if (!s->write_flag)
+ s->buf_end = buffer;
+ else
+ s->buf_end = buffer + buf_size;
+ return 0;
+}
+
+/* NOTE: when opened as read/write, the buffers are only used for
+ reading */
+int url_fopen(ByteIOContext *s, const char *filename, int flags)
+{
+ URLContext *h;
+ int err;
+
+ err = url_open(&h, filename, flags);
+ if (err < 0)
+ return err;
+ err = url_fdopen(s, h);
+ if (err < 0) {
+ url_close(h);
+ return err;
+ }
+ return 0;
+}
+
+int url_fclose(ByteIOContext *s)
+{
+ URLContext *h = s->opaque;
+
+ av_free(s->buffer);
+ memset(s, 0, sizeof(ByteIOContext));
+ return url_close(h);
+}
+
+URLContext *url_fileno(ByteIOContext *s)
+{
+ return s->opaque;
+}
+
+/* XXX: currently size is limited */
+int url_fprintf(ByteIOContext *s, const char *fmt, ...)
+{
+ va_list ap;
+ char buf[4096];
+ int ret;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(buf, sizeof(buf), fmt, ap);
+ va_end(ap);
+ put_buffer(s, buf, strlen(buf));
+ return ret;
+}
+
+/* note: unlike fgets, the EOL character is not returned and a whole
+ line is parsed. return NULL if first char read was EOF */
+char *url_fgets(ByteIOContext *s, char *buf, int buf_size)
+{
+ int c;
+ char *q;
+
+ c = url_fgetc(s);
+ if (c == EOF)
+ return NULL;
+ q = buf;
+ for(;;) {
+ if (c == EOF || c == '\n')
+ break;
+ if ((q - buf) < buf_size - 1)
+ *q++ = c;
+ c = url_fgetc(s);
+ }
+ if (buf_size > 0)
+ *q = '\0';
+ return buf;
+}
+
+/*
+ * Return the maximum packet size associated to packetized buffered file
+ * handle. If the file is not packetized (stream like http or file on
+ * disk), then 0 is returned.
+ *
+ * @param h buffered file handle
+ * @return maximum packet size in bytes
+ */
+int url_fget_max_packet_size(ByteIOContext *s)
+{
+ return s->max_packet_size;
+}
+
+/* buffer handling */
+int url_open_buf(ByteIOContext *s, UINT8 *buf, int buf_size, int flags)
+{
+ return init_put_byte(s, buf, buf_size,
+ (flags & URL_WRONLY) != 0, NULL, NULL, NULL, NULL);
+}
+
+/* return the written or read size */
+int url_close_buf(ByteIOContext *s)
+{
+ put_flush_packet(s);
+ return s->buf_ptr - s->buffer;
+}
+
+/* output in a dynamic buffer */
+
+typedef struct DynBuffer {
+ int pos, size, allocated_size;
+ UINT8 *buffer;
+ int io_buffer_size;
+ UINT8 io_buffer[1];
+} DynBuffer;
+
+static void dyn_buf_write(void *opaque, UINT8 *buf, int buf_size)
+{
+ DynBuffer *d = opaque;
+ int new_size, new_allocated_size;
+ UINT8 *new_buffer;
+
+ /* reallocate buffer if needed */
+ new_size = d->pos + buf_size;
+ new_allocated_size = d->allocated_size;
+ while (new_size > new_allocated_size) {
+ if (!new_allocated_size)
+ new_allocated_size = new_size;
+ else
+ new_allocated_size = (new_allocated_size * 3) / 2 + 1;
+ }
+
+ if (new_allocated_size > d->allocated_size) {
+ new_buffer = av_malloc(new_allocated_size);
+ if (!new_buffer)
+ return;
+ memcpy(new_buffer, d->buffer, d->size);
+ av_free(d->buffer);
+ d->buffer = new_buffer;
+ d->allocated_size = new_allocated_size;
+ }
+ memcpy(d->buffer + d->pos, buf, buf_size);
+ d->pos = new_size;
+ if (d->pos > d->size)
+ d->size = d->pos;
+}
+
+static void dyn_packet_buf_write(void *opaque, UINT8 *buf, int buf_size)
+{
+ unsigned char buf1[4];
+
+ /* packetized write: output the header */
+ buf1[0] = (buf_size >> 24);
+ buf1[1] = (buf_size >> 16);
+ buf1[2] = (buf_size >> 8);
+ buf1[3] = (buf_size);
+ dyn_buf_write(opaque, buf1, 4);
+
+ /* then the data */
+ dyn_buf_write(opaque, buf, buf_size);
+}
+
+static int dyn_buf_seek(void *opaque, offset_t offset, int whence)
+{
+ DynBuffer *d = opaque;
+
+ if (whence == SEEK_CUR)
+ offset += d->pos;
+ else if (whence == SEEK_END)
+ offset += d->size;
+ if (offset < 0 || offset > 0x7fffffffLL)
+ return -1;
+ d->pos = offset;
+ return 0;
+}
+
+static int url_open_dyn_buf_internal(ByteIOContext *s, int max_packet_size)
+{
+ DynBuffer *d;
+ int io_buffer_size, ret;
+
+ if (max_packet_size)
+ io_buffer_size = max_packet_size;
+ else
+ io_buffer_size = 1024;
+
+ d = av_malloc(sizeof(DynBuffer) + io_buffer_size);
+ if (!d)
+ return -1;
+ d->io_buffer_size = io_buffer_size;
+ d->buffer = NULL;
+ d->pos = 0;
+ d->size = 0;
+ d->allocated_size = 0;
+ ret = init_put_byte(s, d->io_buffer, io_buffer_size,
+ 1, d, NULL,
+ max_packet_size ? dyn_packet_buf_write : dyn_buf_write,
+ max_packet_size ? NULL : dyn_buf_seek);
+ if (ret == 0) {
+ s->max_packet_size = max_packet_size;
+ }
+ return ret;
+}
+
+/*
+ * Open a write only memory stream.
+ *
+ * @param s new IO context
+ * @return zero if no error.
+ */
+int url_open_dyn_buf(ByteIOContext *s)
+{
+ return url_open_dyn_buf_internal(s, 0);
+}
+
+/*
+ * Open a write only packetized memory stream with a maximum packet
+ * size of 'max_packet_size'. The stream is stored in a memory buffer
+ * with a big endian 4 byte header giving the packet size in bytes.
+ *
+ * @param s new IO context
+ * @param max_packet_size maximum packet size (must be > 0)
+ * @return zero if no error.
+ */
+int url_open_dyn_packet_buf(ByteIOContext *s, int max_packet_size)
+{
+ if (max_packet_size <= 0)
+ return -1;
+ return url_open_dyn_buf_internal(s, max_packet_size);
+}
+
+/*
+ * Return the written size and a pointer to the buffer. The buffer
+ * must be freed with av_free().
+ * @param s IO context
+ * @param pointer to a byte buffer
+ * @return the length of the byte buffer
+ */
+int url_close_dyn_buf(ByteIOContext *s, UINT8 **pbuffer)
+{
+ DynBuffer *d = s->opaque;
+ int size;
+
+ put_flush_packet(s);
+
+ *pbuffer = d->buffer;
+ size = d->size;
+ av_free(d);
+ return size;
+}
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