Support for the content labelling descriptor

This patch provides decoding and generation of the content labelling descriptor.
Signed-off-by: Jean-Paul Saman <jpsaman@videolan.org>

src/Makefile.am

@@ -41,6 +41,7 @@ pkginclude_HEADERS = dvbpsi.h psi.h descriptor.h demux.h \
                      descriptors/dr_14.h \
                      descriptors/dr_1b.h \
                      descriptors/dr_1c.h \
+                     descriptors/dr_24.h \
 		     descriptors/dr_40.h \
 		     descriptors/dr_41.h \
                      descriptors/dr_42.h \
@@ -101,6 +102,7 @@ descriptors_src = descriptors/dr_02.c \
                   descriptors/dr_14.c \
                   descriptors/dr_1b.c \
                   descriptors/dr_1c.c \
+                  descriptors/dr_24.c \
 		  descriptors/dr_40.c \
 		  descriptors/dr_41.c \
                   descriptors/dr_42.c \

src/descriptors/dr_24.c

+/*
+Copyright (C) 2015 Daniel Kamil Kozar
+
+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 2.1 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+
+#if defined(HAVE_INTTYPES_H)
+#include <inttypes.h>
+#elif defined(HAVE_STDINT_H)
+#include <stdint.h>
+#endif
+
+#include "../dvbpsi.h"
+#include "../dvbpsi_private.h"
+#include "../descriptor.h"
+
+#include "dr_24.h"
+
+/* the minimum size of a valid content labelling descriptor. it consists of
+ * metadata_application_format, content_{reference_id_record_flag, time_base_
+ * indicator}, and a reserved field. they all sum up to 24 bits. */
+#define DR_24_MIN_SIZE 3
+
+static int decode_content_reference_id(dvbpsi_content_labelling_dr_t *p_decoded,
+    const uint8_t **pp_data, uint8_t *pi_left)
+{
+    uint8_t i_left = *pi_left;
+    const uint8_t *p_data = *pp_data;
+
+    if(i_left < 1)
+        return 1;
+
+    p_decoded->i_content_reference_id_record_length = *p_data;
+    i_left--; p_data++;
+
+    /* H.222.0 says that content_reference_id_record_length "shall not be coded
+     * with the value '0'". reject such data as invalid. */
+    if(i_left < p_decoded->i_content_reference_id_record_length ||
+      p_decoded->i_content_reference_id_record_length == 0)
+        return 1;
+
+    p_decoded->p_content_reference_id = malloc(
+        p_decoded->i_content_reference_id_record_length);
+    if(!p_decoded->p_content_reference_id)
+        return 1;
+
+    memcpy(p_decoded->p_content_reference_id, p_data,
+        p_decoded->i_content_reference_id_record_length);
+    i_left -= p_decoded->i_content_reference_id_record_length;
+    p_data += p_decoded->i_content_reference_id_record_length;
+
+    *pp_data = p_data;
+    *pi_left = i_left;
+
+    return 0;
+}
+
+static int decode_content_time_base_indicator(dvbpsi_content_labelling_dr_t
+    *p_decoded, const uint8_t **pp_data, uint8_t *pi_left)
+{
+    const uint8_t *p_data = *pp_data;
+    uint8_t i_left = *pi_left;
+
+    if(p_decoded->i_content_time_base_indicator == 1 ||
+        p_decoded->i_content_time_base_indicator == 2)
+    {
+        if(i_left < 10)
+            return 1;
+
+        p_decoded->i_content_time_base_value =
+            (((uint64_t)(p_data[0] & 0x01)) << 32) |
+            ((uint64_t)p_data[1] << 24) |
+            ((uint64_t)p_data[2] << 16) |
+            ((uint64_t)p_data[3] <<  8) |
+            (uint64_t)p_data[4];
+
+        p_decoded->i_metadata_time_base_value =
+            (((uint64_t)(p_data[5] & 0x01)) << 32) |
+            ((uint64_t)p_data[6] << 24) |
+            ((uint64_t)p_data[7] << 16) |
+            ((uint64_t)p_data[8] <<  8) |
+            (uint64_t)p_data[9];
+
+        p_data += 10; i_left -= 10;
+    }
+
+    if(p_decoded->i_content_time_base_indicator == 2)
+    {
+        if(i_left < 1)
+            return 1;
+
+        p_decoded->i_contentId = *p_data & 0x7f;
+        p_data++; i_left--;
+    }
+
+    if(p_decoded->i_content_time_base_indicator >= 3 &&
+        p_decoded->i_content_time_base_indicator <= 7)
+    {
+        if(i_left < 1)
+            return 1;
+
+        p_decoded->i_time_base_association_data_length = *p_data;
+        p_data++; i_left--;
+
+        if(i_left < p_decoded->i_time_base_association_data_length)
+            return 1;
+
+        if(p_decoded->i_time_base_association_data_length)
+        {
+            p_decoded->p_time_base_association_data = malloc(
+                p_decoded->i_time_base_association_data_length);
+            if(!p_decoded->p_time_base_association_data)
+                return 1;
+
+            memcpy(p_decoded->p_time_base_association_data, p_data,
+                p_decoded->i_time_base_association_data_length);
+        }
+
+        p_data += p_decoded->i_time_base_association_data_length;
+        i_left -= p_decoded->i_time_base_association_data_length;
+    }
+
+    *pp_data = p_data;
+    *pi_left = i_left;
+
+    return 0;
+}
+
+dvbpsi_content_labelling_dr_t* dvbpsi_DecodeContentLabellingDr(
+                                      dvbpsi_descriptor_t * p_descriptor)
+{
+    dvbpsi_content_labelling_dr_t *p_decoded;
+    const uint8_t *p_data = p_descriptor->p_data;
+    uint8_t i_left = p_descriptor->i_length;
+
+    /* check the tag. */
+    if (!dvbpsi_CanDecodeAsDescriptor(p_descriptor, 0x24))
+        return NULL;
+
+    /* don't decode twice. */
+    if (dvbpsi_IsDescriptorDecoded(p_descriptor))
+        return p_descriptor->p_decoded;
+
+    /* simplest descriptors of this type contain 3 bytes of payload. */
+    if (p_descriptor->i_length < DR_24_MIN_SIZE)
+        return NULL;
+
+    p_decoded = malloc(sizeof(*p_decoded));
+    if (!p_decoded)
+        return NULL;
+
+    /* set the pointers to NULL so we can safely free() them in err: */
+    p_decoded->p_content_reference_id = NULL;
+    p_decoded->p_time_base_association_data = NULL;
+    p_decoded->p_private_data = NULL;
+
+    p_decoded->i_metadata_application_format =
+        ((uint16_t)p_data[0] << 8) | (uint16_t)p_data[1];
+    i_left -= 2; p_data += 2;
+
+    if(p_decoded->i_metadata_application_format == 0xFFFF)
+    {
+        if(i_left < 4)
+            goto err;
+
+        p_decoded->i_metadata_application_format_identifier =
+            ((uint32_t)p_data[0] << 24) |
+            ((uint32_t)p_data[1] << 16) |
+            ((uint32_t)p_data[2] <<  8) |
+            (uint32_t)p_data[3];
+        i_left -= 4; p_data += 4;
+    }
+
+    if(i_left < 1)
+        goto err;
+
+    p_decoded->b_content_reference_id_record_flag = (*p_data & 0x80);
+    p_decoded->i_content_time_base_indicator = ((*p_data & 0x78) >> 3);
+    i_left--; p_data++;
+
+    if(p_decoded->b_content_reference_id_record_flag &&
+        decode_content_reference_id(p_decoded, &p_data, &i_left) != 0)
+        goto err;
+
+    if(p_decoded->i_content_time_base_indicator &&
+        decode_content_time_base_indicator(p_decoded, &p_data, &i_left) != 0)
+        goto err;
+
+    p_decoded->i_private_data_len = i_left;
+    if(p_decoded->i_private_data_len)
+    {
+        p_decoded->p_private_data = malloc(p_decoded->i_private_data_len);
+        if(!p_decoded->p_private_data)
+            goto err;
+
+        memcpy(p_decoded->p_private_data, p_data, p_decoded->i_private_data_len);
+    }
+
+    p_descriptor->p_decoded = p_decoded;
+    return p_decoded;
+
+err:
+    free(p_decoded->p_private_data);
+    free(p_decoded->p_time_base_association_data);
+    free(p_decoded->p_content_reference_id);
+    free(p_decoded);
+    return NULL;
+}
+
+static unsigned int generate_get_descriptor_size(const
+    dvbpsi_content_labelling_dr_t * p_decoded)
+{
+    unsigned int size = DR_24_MIN_SIZE + p_decoded->i_private_data_len;
+
+    if(p_decoded->i_metadata_application_format == 0xFFFF)
+        size += 4;
+
+    if(p_decoded->b_content_reference_id_record_flag)
+        size += p_decoded->i_content_reference_id_record_length + 1;
+
+    if(p_decoded->i_content_time_base_indicator == 1 ||
+        p_decoded->i_content_time_base_indicator == 2)
+        size += 10;
+
+    if(p_decoded->i_content_time_base_indicator == 2)
+        size += 1;
+
+    if(p_decoded->i_content_time_base_indicator >= 3 &&
+        p_decoded->i_content_time_base_indicator <= 7)
+        size += p_decoded->i_time_base_association_data_length + 1;
+
+    return size;
+}
+
+static bool generate_check_struct_valid(const
+    dvbpsi_content_labelling_dr_t * p_decoded)
+{
+    /* check if the pointers are valid if relevant sizes are nonzero. also,
+     * check if i_content_reference_id_record_length isn't zero if the flag is
+     * set, as this is explicitly forbidden by H.222.0. */
+    if((p_decoded->b_content_reference_id_record_flag &&
+        !p_decoded->i_content_reference_id_record_length) ||
+        (p_decoded->i_content_reference_id_record_length &&
+        !p_decoded->p_content_reference_id))
+        return false;
+
+    if(p_decoded->i_time_base_association_data_length &&
+        !p_decoded->p_time_base_association_data)
+        return false;
+
+    if(p_decoded->i_private_data_len && !p_decoded->p_private_data)
+        return false;
+
+    return true;
+}
+
+dvbpsi_descriptor_t * dvbpsi_GenContentLabellingDr(
+                                      dvbpsi_content_labelling_dr_t * p_decoded)
+{
+    unsigned int size;
+    dvbpsi_descriptor_t * p_descriptor;
+    uint8_t *p_data;
+
+    if(!generate_check_struct_valid(p_decoded))
+        return NULL;
+
+    size = generate_get_descriptor_size(p_decoded);
+    if(size > 253) /* maximum possible descriptor payload size. */
+        return NULL;
+
+    p_descriptor = dvbpsi_NewDescriptor(0x24, size, NULL);
+    if (!p_descriptor)
+        return NULL;
+
+    p_data = p_descriptor->p_data;
+
+    p_data[0] = (p_decoded->i_metadata_application_format & 0xFF00) >> 8;
+    p_data[1] = (p_decoded->i_metadata_application_format & 0x00FF);
+    p_data += 2;
+
+    if(p_decoded->i_metadata_application_format == 0xFFFF)
+    {
+        p_data[0] = (p_decoded->i_metadata_application_format_identifier & 0xFF000000) >> 24;
+        p_data[1] = (p_decoded->i_metadata_application_format_identifier & 0x00FF0000) >> 16;
+        p_data[2] = (p_decoded->i_metadata_application_format_identifier & 0x0000FF00) >> 8;
+        p_data[3] = (p_decoded->i_metadata_application_format_identifier & 0x000000FF);
+        p_data += 4;
+    }
+
+    *p_data = ((p_decoded->b_content_reference_id_record_flag ? 1 : 0) << 7) |
+        ((p_decoded->i_content_time_base_indicator & 0xf) << 6) |
+        0x07;
+    p_data++;
+
+    if(p_decoded->b_content_reference_id_record_flag)
+    {
+        *p_data = p_decoded->i_content_reference_id_record_length;
+        memcpy(p_data + 1, p_decoded->p_content_reference_id,
+            p_decoded->i_content_reference_id_record_length);
+        p_data += (p_decoded->i_content_reference_id_record_length + 1);
+    }
+
+    if(p_decoded->i_content_time_base_indicator == 1 ||
+        p_decoded->i_content_time_base_indicator == 2)
+    {
+        p_data[0] = 0xfe | ((p_decoded->i_content_time_base_value & 0x100000000) >> 32);
+        p_data[1] = (p_decoded->i_content_time_base_value & 0xFF000000) >> 24;
+        p_data[2] = (p_decoded->i_content_time_base_value & 0x00FF0000) >> 16;
+        p_data[3] = (p_decoded->i_content_time_base_value & 0x0000FF00) >> 8;
+        p_data[4] = (p_decoded->i_content_time_base_value & 0x000000FF);
+
+        p_data[5] = 0xfe | ((p_decoded->i_metadata_time_base_value & 0x100000000) >> 32);
+        p_data[6] = (p_decoded->i_metadata_time_base_value & 0xFF000000) >> 24;
+        p_data[7] = (p_decoded->i_metadata_time_base_value & 0x00FF0000) >> 16;
+        p_data[8] = (p_decoded->i_metadata_time_base_value & 0x0000FF00) >> 8;
+        p_data[9] = (p_decoded->i_metadata_time_base_value & 0x000000FF);
+
+        p_data += 10;
+    }
+
+    if(p_decoded->i_content_time_base_indicator == 2)
+    {
+        *p_data = 0x80 | (p_decoded->i_contentId & 0x7f);
+        p_data++;
+    }
+
+    if(p_decoded->i_content_time_base_indicator >= 3 &&
+        p_decoded->i_content_time_base_indicator <= 7)
+    {
+        *p_data = p_decoded->i_time_base_association_data_length;
+        memcpy(p_data + 1, p_decoded->p_time_base_association_data,
+            p_decoded->i_time_base_association_data_length);
+        p_data += (p_decoded->i_time_base_association_data_length + 1);
+    }
+
+    memcpy(p_data, p_decoded->p_private_data, p_decoded->i_private_data_len);
+    return p_descriptor;
+}

src/descriptors/dr_24.h

+/*
+Copyright (C) 2015 Daniel Kamil Kozar
+
+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 2.1 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+/*!
+ * \file <dr_24.h>
+ * \author Daniel Kamil Kozar <dkk089@gmail.com>
+ * \brief Application interface for the content labelling descriptor decoder and
+ * generator.
+ *
+ * Application interface for the content labelling descriptor decoder and
+ * generator. This descriptor's definition can be found in ISO/IEC 13818-1:2015
+ * section 2.6.56.
+ */
+
+#ifndef _DVBPSI_DR_24_H_
+#define _DVBPSI_DR_24_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*!
+ * \struct dvbpsi_content_labelling_dr_s
+ * \brief Content labelling descriptor structure.
+ *
+ * This structure is used to store a decoded content labelling descriptor.
+ * (ISO/IEC 13818-1 section 2.6.56).
+ */
+
+/*!
+ * \typedef struct dvbpsi_content_labelling_dr_s dvbpsi_content_labelling_dr_t
+ * \brief dvbpsi_content_labelling_dr_t type definition.
+ */
+typedef struct dvbpsi_content_labelling_dr_s
+{
+    uint16_t i_metadata_application_format; /*!< metadata_application_format */
+
+    /*! metadata_application_format_identifier
+     * \warning Valid only if \c i_metadata_application_format is \c 0xFFFF . */
+    uint32_t i_metadata_application_format_identifier;
+
+    /*! content_reference_id_record_flag */
+    bool b_content_reference_id_record_flag;
+    uint8_t i_content_time_base_indicator; /*!< content_time_base_indicator */
+
+    /*! content_reference_id_record_length
+     * \warning Valid only if \c b_content_reference_id_record_flag is true. */
+    uint8_t i_content_reference_id_record_length;
+
+    /*! content_reference_id_byte
+     * An array of \c i_content_reference_id_record_length bytes. Memory is
+     * allocated by the decoder when decoding, and by the caller when generating.
+     * \warning Valid only if \c b_content_reference_id_record_flag is true. */
+    uint8_t *p_content_reference_id;
+
+    /*! content_time_base_value
+     * \warning Valid only if \c i_content_time_base_indicator is 1 or 2. */
+    uint64_t i_content_time_base_value;
+
+    /*! metadata_time_base_value
+     * \warning Valid only if \c i_content_time_base_indicator is 1 or 2. */
+    uint64_t i_metadata_time_base_value;
+
+    /*! contentId
+     * \warning Valid only if \c i_content_time_base_indicator is 2. */
+    uint8_t i_contentId;
+
+    /*! time_base_association_data_length
+     * \warning Valid only if \c i_content_time_base_indicator is 3, 4, 5, 6,
+     * or 7. */
+    uint8_t i_time_base_association_data_length;
+
+    /*! time_base_association_data
+     * An array of \c i_time_base_association_data_length bytes. Memory is
+     * allocated by the decoder when decoding, and by the caller when generating.
+     * \note This field is marked as reserved, but access to it is nevertheless
+     * provided if applications want to use it.
+     * \warning Valid only if \c i_content_time_base_indicator is 3, 4, 5, 6,
+     * or 7. */
+    uint8_t *p_time_base_association_data;
+
+    /*! private_data_len */
+    uint8_t i_private_data_len;
+
+    /*! private_data
+     * \note An array of \c i_private_data_len bytes at the end of the
+     * descriptor. Memory is allocated by the decoder when decoding, and by the
+     * caller when generating. */
+    uint8_t *p_private_data;
+} dvbpsi_content_labelling_dr_t;
+
+/*!
+ * \brief Content labelling descriptor decoder.
+ * \param p_descriptor pointer to the descriptor structure
+ * \return A pointer to a new content labelling descriptor structure which
+ * contains the decoded data.
+ */
+dvbpsi_content_labelling_dr_t* dvbpsi_DecodeContentLabellingDr(
+                                      dvbpsi_descriptor_t * p_descriptor);
+
+/*!
+ * \brief Content labelling descriptor generator.
+ * \param p_decoded pointer to a decoded content labelling descriptor structure.
+ * \return a pointer to a new descriptor structure which contains encoded data.
+ */
+dvbpsi_descriptor_t * dvbpsi_GenContentLabellingDr(
+                                      dvbpsi_content_labelling_dr_t * p_decoded);
+
+#ifdef __cplusplus
+}
+#endif
+
+#else
+#error "Multiple inclusions of dr_24.h"
+#endif