Merge "Fix parsing of gps location atom in mp4"

#include <ctype.h>

#include <inttypes.h>

#include <memory>

#include <stdint.h>

#include <stdlib.h>

#include <string.h>

        {

            *offset += chunk_size;

            // Best case the total data length inside "\xA9xyz" box

            // would be 8, for instance "\xA9xyz" + "\x00\x04\x15\xc7" + "0+0/",

            // where "\x00\x04" is the text string length with value = 4,

            // "\0x15\xc7" is the language code = en, and "0+0" is a

            // Best case the total data length inside "\xA9xyz" box would

            // be 9, for instance "\xA9xyz" + "\x00\x05\x15\xc7" + "+0+0/",

            // where "\x00\x05" is the text string length with value = 5,

            // "\0x15\xc7" is the language code = en, and "+0+0/" is a

            // location (string) value with longitude = 0 and latitude = 0.

            if (chunk_data_size < 8) {

            // Since some devices encountered in the wild omit the trailing

            // slash, we'll allow that.

            if (chunk_data_size < 8) { // 8 instead of 9 to allow for missing /

                return ERROR_MALFORMED;

            }

            // Worst case the location string length would be 18,

            // for instance +90.0000-180.0000, without the trailing "/" and

            // the string length + language code, and some devices include

            // an additional 8 bytes of altitude, e.g. +007.186

            char buffer[18 + 8];

            uint16_t len;

            if (!mDataSource->getUInt16(data_offset, &len)) {

                return ERROR_IO;

            }

            // Substracting 5 from the data size is because the text string length +

            // language code takes 4 bytes, and the trailing slash "/" takes 1 byte.

            off64_t location_length = chunk_data_size - 5;

            if (location_length >= (off64_t) sizeof(buffer)) {

            // allow "+0+0" without trailing slash

            if (len < 4 || len > chunk_data_size - 4) {

                return ERROR_MALFORMED;

            }

            // The location string following the language code is formatted

            // according to ISO 6709:2008 (https://en.wikipedia.org/wiki/ISO_6709).

            // Allocate 2 extra bytes, in case we need to add a trailing slash,

            // and to add a terminating 0.

            std::unique_ptr<char[]> buffer(new char[len+2]());

            if (!buffer) {

                return NO_MEMORY;

            }

            if (mDataSource->readAt(

                        data_offset + 4, buffer, location_length) < location_length) {

                        data_offset + 4, &buffer[0], len) < len) {

                return ERROR_IO;

            }

            buffer[location_length] = '\0';

            mFileMetaData->setCString(kKeyLocation, buffer);

            len = strlen(&buffer[0]);

            if (len < 4) {

                return ERROR_MALFORMED;

            }

            // Add a trailing slash if there wasn't one.

            if (buffer[len - 1] != '/') {

                buffer[len] = '/';

            }

            mFileMetaData->setCString(kKeyLocation, &buffer[0]);

            break;

        }