| // Copyright 2019 Joe Drago. All rights reserved. |
| // SPDX-License-Identifier: BSD-2-Clause |
| |
| #include "avif/internal.h" |
| |
| #include <assert.h> |
| #include <inttypes.h> |
| #include <stdint.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| // --------------------------------------------------------------------------- |
| // avifROStream |
| |
| const uint8_t * avifROStreamCurrent(avifROStream * stream) |
| { |
| return stream->raw->data + stream->offset; |
| } |
| |
| void avifROStreamStart(avifROStream * stream, avifROData * raw, avifDiagnostics * diag, const char * diagContext) |
| { |
| stream->raw = raw; |
| stream->offset = 0; |
| stream->numUsedBitsInPartialByte = 0; |
| stream->diag = diag; |
| stream->diagContext = diagContext; |
| |
| // If diag is non-NULL, diagContext must also be non-NULL |
| assert(!stream->diag || stream->diagContext); |
| } |
| |
| avifBool avifROStreamHasBytesLeft(const avifROStream * stream, size_t byteCount) |
| { |
| return byteCount <= (stream->raw->size - stream->offset); |
| } |
| |
| size_t avifROStreamRemainingBytes(const avifROStream * stream) |
| { |
| return stream->raw->size - stream->offset; |
| } |
| |
| size_t avifROStreamOffset(const avifROStream * stream) |
| { |
| return stream->offset; |
| } |
| |
| void avifROStreamSetOffset(avifROStream * stream, size_t offset) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| stream->offset = offset; |
| if (stream->offset > stream->raw->size) { |
| stream->offset = stream->raw->size; |
| } |
| } |
| |
| avifBool avifROStreamSkip(avifROStream * stream, size_t byteCount) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| if (!avifROStreamHasBytesLeft(stream, byteCount)) { |
| avifDiagnosticsPrintf(stream->diag, "%s: Failed to skip %zu bytes, truncated data?", stream->diagContext, byteCount); |
| return AVIF_FALSE; |
| } |
| stream->offset += byteCount; |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamRead(avifROStream * stream, uint8_t * data, size_t size) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| if (!avifROStreamHasBytesLeft(stream, size)) { |
| avifDiagnosticsPrintf(stream->diag, "%s: Failed to read %zu bytes, truncated data?", stream->diagContext, size); |
| return AVIF_FALSE; |
| } |
| |
| memcpy(data, stream->raw->data + stream->offset, size); |
| stream->offset += size; |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadUX8(avifROStream * stream, uint64_t * v, uint64_t factor) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| if (factor == 0) { |
| // Don't read anything, just set to 0 |
| *v = 0; |
| } else if (factor == 1) { |
| uint8_t tmp; |
| AVIF_CHECK(avifROStreamRead(stream, &tmp, 1)); |
| *v = tmp; |
| } else if (factor == 2) { |
| uint16_t tmp; |
| AVIF_CHECK(avifROStreamReadU16(stream, &tmp)); |
| *v = tmp; |
| } else if (factor == 4) { |
| uint32_t tmp; |
| AVIF_CHECK(avifROStreamReadU32(stream, &tmp)); |
| *v = tmp; |
| } else if (factor == 8) { |
| uint64_t tmp; |
| AVIF_CHECK(avifROStreamReadU64(stream, &tmp)); |
| *v = tmp; |
| } else { |
| // Unsupported factor |
| avifDiagnosticsPrintf(stream->diag, "%s: Failed to read UX8 value; Unsupported UX8 factor [%" PRIu64 "]", stream->diagContext, factor); |
| return AVIF_FALSE; |
| } |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadU16(avifROStream * stream, uint16_t * v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECK(avifROStreamRead(stream, (uint8_t *)v, sizeof(uint16_t))); |
| *v = avifNTOHS(*v); |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadU16Endianness(avifROStream * stream, uint16_t * v, avifBool littleEndian) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECK(avifROStreamRead(stream, (uint8_t *)v, sizeof(uint16_t))); |
| *v = littleEndian ? avifCTOHS(*v) : avifNTOHS(*v); |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadU32(avifROStream * stream, uint32_t * v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECK(avifROStreamRead(stream, (uint8_t *)v, sizeof(uint32_t))); |
| *v = avifNTOHL(*v); |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadU32Endianness(avifROStream * stream, uint32_t * v, avifBool littleEndian) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECK(avifROStreamRead(stream, (uint8_t *)v, sizeof(uint32_t))); |
| *v = littleEndian ? avifCTOHL(*v) : avifNTOHL(*v); |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadU64(avifROStream * stream, uint64_t * v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECK(avifROStreamRead(stream, (uint8_t *)v, sizeof(uint64_t))); |
| *v = avifNTOH64(*v); |
| return AVIF_TRUE; |
| } |
| |
| // Override of avifROStreamReadBits() for convenient uint8_t output. |
| avifBool avifROStreamReadBits8(avifROStream * stream, uint8_t * v, size_t bitCount) |
| { |
| assert(bitCount <= sizeof(*v) * 8); |
| uint32_t v32; |
| if (!avifROStreamReadBits(stream, &v32, bitCount)) { |
| return AVIF_FALSE; |
| } |
| *v = (uint8_t)v32; |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadBits(avifROStream * stream, uint32_t * v, size_t bitCount) |
| { |
| assert(bitCount <= sizeof(*v) * 8); |
| *v = 0; |
| while (bitCount) { |
| if (stream->numUsedBitsInPartialByte == 0) { |
| AVIF_CHECK(avifROStreamSkip(stream, sizeof(uint8_t))); // Book a new partial byte in the stream. |
| } |
| assert(stream->offset > 0); |
| const uint8_t * packedBits = stream->raw->data + stream->offset - 1; |
| |
| const size_t numBits = AVIF_MIN(bitCount, 8 - stream->numUsedBitsInPartialByte); |
| stream->numUsedBitsInPartialByte += numBits; |
| bitCount -= numBits; |
| // The stream bits are packed starting with the most significant bit of the first input byte. |
| // This way, packed bits can be found in the same order in the bit stream. |
| const uint32_t bits = (*packedBits >> (8 - stream->numUsedBitsInPartialByte)) & ((1 << numBits) - 1); |
| // The value bits are ordered from the most significant bit to the least significant bit. |
| // In the case where avifROStreamReadBits() is used to parse the unsigned integer value *v |
| // over multiple aligned bytes, this order corresponds to big endianness. |
| *v |= bits << bitCount; |
| |
| if (stream->numUsedBitsInPartialByte == 8) { |
| // Start a new partial byte the next time a bit is needed. |
| stream->numUsedBitsInPartialByte = 0; |
| } |
| } |
| return AVIF_TRUE; |
| } |
| |
| // Based on https://sqlite.org/src4/doc/trunk/www/varint.wiki. |
| avifBool avifROStreamReadVarInt(avifROStream * stream, uint32_t * v) |
| { |
| uint32_t a[5]; |
| AVIF_CHECK(avifROStreamReadBits(stream, &a[0], 8)); |
| if (a[0] <= 240) { |
| *v = a[0]; |
| } else { |
| AVIF_CHECK(avifROStreamReadBits(stream, &a[1], 8)); |
| if (a[0] <= 248) { |
| *v = 240 + 256 * (a[0] - 241) + a[1]; |
| } else { |
| AVIF_CHECK(avifROStreamReadBits(stream, &a[2], 8)); |
| if (a[0] == 249) { |
| *v = 2288 + 256 * a[1] + a[2]; |
| } else { |
| AVIF_CHECK(avifROStreamReadBits(stream, &a[3], 8)); |
| if (a[0] == 250) { |
| *v = (a[3] << 16) | (a[2] << 8) | a[1]; |
| } else { |
| // TODO(yguyon): Use values of a[0] in range [252-255] (avoid pessimization). |
| AVIF_CHECK(avifROStreamReadBits(stream, &a[4], 8)); |
| *v = (a[4] << 24) | (a[3] << 16) | (a[2] << 8) | a[1]; |
| } |
| } |
| } |
| } |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadString(avifROStream * stream, char * output, size_t outputSize) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| |
| // Check for the presence of a null terminator in the stream. |
| size_t remainingBytes = avifROStreamRemainingBytes(stream); |
| const uint8_t * p = avifROStreamCurrent(stream); |
| avifBool foundNullTerminator = AVIF_FALSE; |
| for (size_t i = 0; i < remainingBytes; ++i) { |
| if (p[i] == 0) { |
| foundNullTerminator = AVIF_TRUE; |
| break; |
| } |
| } |
| if (!foundNullTerminator) { |
| avifDiagnosticsPrintf(stream->diag, "%s: Failed to find a NULL terminator when reading a string", stream->diagContext); |
| return AVIF_FALSE; |
| } |
| |
| const char * streamString = (const char *)p; |
| size_t stringLen = strlen(streamString); |
| stream->offset += stringLen + 1; // update the stream to have read the "whole string" in |
| |
| if (output && outputSize) { |
| // clamp to our output buffer |
| if (stringLen >= outputSize) { |
| stringLen = outputSize - 1; |
| } |
| memcpy(output, streamString, stringLen); |
| output[stringLen] = 0; |
| } |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadBoxHeaderPartial(avifROStream * stream, avifBoxHeader * header) |
| { |
| size_t startOffset = stream->offset; |
| |
| uint32_t smallSize; |
| AVIF_CHECK(avifROStreamReadU32(stream, &smallSize)); |
| AVIF_CHECK(avifROStreamRead(stream, header->type, 4)); |
| |
| uint64_t size = smallSize; |
| if (size == 1) { |
| AVIF_CHECK(avifROStreamReadU64(stream, &size)); |
| } |
| |
| if (!memcmp(header->type, "uuid", 4)) { |
| AVIF_CHECK(avifROStreamSkip(stream, 16)); |
| } |
| |
| size_t bytesRead = stream->offset - startOffset; |
| if ((size < bytesRead) || ((size - bytesRead) > SIZE_MAX)) { |
| avifDiagnosticsPrintf(stream->diag, "%s: Header size overflow check failure", stream->diagContext); |
| return AVIF_FALSE; |
| } |
| header->size = (size_t)(size - bytesRead); |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadBoxHeader(avifROStream * stream, avifBoxHeader * header) |
| { |
| AVIF_CHECK(avifROStreamReadBoxHeaderPartial(stream, header)); |
| if (header->size > avifROStreamRemainingBytes(stream)) { |
| avifDiagnosticsPrintf(stream->diag, "%s: Child box too large, possibly truncated data", stream->diagContext); |
| return AVIF_FALSE; |
| } |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadVersionAndFlags(avifROStream * stream, uint8_t * version, uint32_t * flags) |
| { |
| uint8_t versionAndFlags[4]; |
| AVIF_CHECK(avifROStreamRead(stream, versionAndFlags, 4)); |
| if (version) { |
| *version = versionAndFlags[0]; |
| } |
| if (flags) { |
| *flags = (versionAndFlags[1] << 16) + (versionAndFlags[2] << 8) + (versionAndFlags[3] << 0); |
| } |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadAndEnforceVersion(avifROStream * stream, uint8_t enforcedVersion) |
| { |
| uint8_t version; |
| AVIF_CHECK(avifROStreamReadVersionAndFlags(stream, &version, NULL)); |
| if (version != enforcedVersion) { |
| avifDiagnosticsPrintf(stream->diag, "%s: Expecting box version %u, got version %u", stream->diagContext, enforcedVersion, version); |
| return AVIF_FALSE; |
| } |
| return AVIF_TRUE; |
| } |
| |
| // --------------------------------------------------------------------------- |
| // avifRWStream |
| |
| #define AVIF_STREAM_BUFFER_INCREMENT (1024 * 1024) |
| static avifResult makeRoom(avifRWStream * stream, size_t size) |
| { |
| size_t neededSize = stream->offset + size; |
| size_t newSize = stream->raw->size; |
| while (newSize < neededSize) { |
| newSize += AVIF_STREAM_BUFFER_INCREMENT; |
| } |
| return avifRWDataRealloc(stream->raw, newSize); |
| } |
| |
| void avifRWStreamStart(avifRWStream * stream, avifRWData * raw) |
| { |
| stream->raw = raw; |
| stream->offset = 0; |
| stream->numUsedBitsInPartialByte = 0; |
| } |
| |
| size_t avifRWStreamOffset(const avifRWStream * stream) |
| { |
| return stream->offset; |
| } |
| |
| void avifRWStreamSetOffset(avifRWStream * stream, size_t offset) |
| { |
| stream->offset = offset; |
| if (stream->offset > stream->raw->size) { |
| stream->offset = stream->raw->size; |
| } |
| } |
| |
| void avifRWStreamFinishWrite(avifRWStream * stream) |
| { |
| if (stream->raw->size != stream->offset) { |
| if (stream->offset) { |
| stream->raw->size = stream->offset; |
| } else { |
| avifRWDataFree(stream->raw); |
| } |
| } |
| } |
| |
| avifResult avifRWStreamWrite(avifRWStream * stream, const void * data, size_t size) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| if (size) { |
| AVIF_CHECKRES(makeRoom(stream, size)); |
| memcpy(stream->raw->data + stream->offset, data, size); |
| stream->offset += size; |
| } |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteChars(avifRWStream * stream, const char * chars, size_t size) |
| { |
| return avifRWStreamWrite(stream, chars, size); |
| } |
| |
| avifResult avifRWStreamWriteFullBox(avifRWStream * stream, const char * type, size_t contentSize, int version, uint32_t flags, avifBoxMarker * marker) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| if (marker) { |
| *marker = stream->offset; |
| } |
| size_t headerSize = sizeof(uint32_t) + 4 /* size of type */; |
| if (version != -1) { |
| headerSize += 4; |
| } |
| |
| AVIF_CHECKRES(makeRoom(stream, headerSize)); |
| memset(stream->raw->data + stream->offset, 0, headerSize); |
| uint32_t noSize = avifHTONL((uint32_t)(headerSize + contentSize)); |
| memcpy(stream->raw->data + stream->offset, &noSize, sizeof(uint32_t)); |
| memcpy(stream->raw->data + stream->offset + 4, type, 4); |
| if (version != -1) { |
| stream->raw->data[stream->offset + 8] = (uint8_t)version; |
| stream->raw->data[stream->offset + 9] = (uint8_t)((flags >> 16) & 0xff); |
| stream->raw->data[stream->offset + 10] = (uint8_t)((flags >> 8) & 0xff); |
| stream->raw->data[stream->offset + 11] = (uint8_t)((flags >> 0) & 0xff); |
| } |
| stream->offset += headerSize; |
| |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteBox(avifRWStream * stream, const char * type, size_t contentSize, avifBoxMarker * marker) |
| { |
| return avifRWStreamWriteFullBox(stream, type, contentSize, -1, 0, marker); |
| } |
| |
| void avifRWStreamFinishBox(avifRWStream * stream, avifBoxMarker marker) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| uint32_t noSize = avifHTONL((uint32_t)(stream->offset - marker)); |
| memcpy(stream->raw->data + marker, &noSize, sizeof(uint32_t)); |
| } |
| |
| avifResult avifRWStreamWriteU8(avifRWStream * stream, uint8_t v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECKRES(makeRoom(stream, 1)); |
| stream->raw->data[stream->offset] = v; |
| stream->offset += 1; |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteU16(avifRWStream * stream, uint16_t v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| const size_t size = sizeof(uint16_t); |
| AVIF_CHECKRES(makeRoom(stream, size)); |
| v = avifHTONS(v); |
| memcpy(stream->raw->data + stream->offset, &v, size); |
| stream->offset += size; |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteU32(avifRWStream * stream, uint32_t v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| const size_t size = sizeof(uint32_t); |
| AVIF_CHECKRES(makeRoom(stream, size)); |
| v = avifHTONL(v); |
| memcpy(stream->raw->data + stream->offset, &v, size); |
| stream->offset += size; |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteU64(avifRWStream * stream, uint64_t v) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| const size_t size = sizeof(uint64_t); |
| AVIF_CHECKRES(makeRoom(stream, size)); |
| v = avifHTON64(v); |
| memcpy(stream->raw->data + stream->offset, &v, size); |
| stream->offset += size; |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteZeros(avifRWStream * stream, size_t byteCount) |
| { |
| assert(stream->numUsedBitsInPartialByte == 0); // Byte alignment is required. |
| AVIF_CHECKRES(makeRoom(stream, byteCount)); |
| memset(stream->raw->data + stream->offset, 0, byteCount); |
| stream->offset += byteCount; |
| return AVIF_RESULT_OK; |
| } |
| |
| avifResult avifRWStreamWriteBits(avifRWStream * stream, uint32_t v, size_t bitCount) |
| { |
| assert(((uint64_t)v >> bitCount) == 0); // (uint32_t >> 32 is undefined behavior) |
| while (bitCount) { |
| if (stream->numUsedBitsInPartialByte == 0) { |
| AVIF_CHECKRES(makeRoom(stream, 1)); // Book a new partial byte in the stream. |
| stream->raw->data[stream->offset] = 0; |
| stream->offset += 1; |
| } |
| assert(stream->offset > 0); |
| uint8_t * packedBits = stream->raw->data + stream->offset - 1; |
| |
| const size_t numBits = AVIF_MIN(bitCount, 8 - stream->numUsedBitsInPartialByte); |
| stream->numUsedBitsInPartialByte += numBits; |
| bitCount -= numBits; |
| // Order the input bits from the most significant bit to the least significant bit. |
| // In the case where avifRWStreamWriteBits() is used to write the unsigned integer value v |
| // over multiple aligned bytes, this order corresponds to big endianness. |
| const uint32_t bits = (v >> bitCount) & ((1 << numBits) - 1); |
| // Pack bits starting with the most significant bit of the first output byte. |
| // This way, packed bits can be found in the same order in the bit stream. |
| *packedBits |= bits << (8 - stream->numUsedBitsInPartialByte); |
| |
| if (stream->numUsedBitsInPartialByte == 8) { |
| // Start a new partial byte the next time a bit is needed. |
| stream->numUsedBitsInPartialByte = 0; |
| } |
| } |
| return AVIF_RESULT_OK; |
| } |
| |
| // Based on https://sqlite.org/src4/doc/trunk/www/varint.wiki. |
| avifResult avifRWStreamWriteVarInt(avifRWStream * stream, uint32_t v) |
| { |
| if (v <= 240) { |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, v, 8)); |
| } else if (v <= 2287) { |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v - 240) / 256 + 241, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v - 240) % 256, 8)); |
| } else if (v <= 67823) { |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, 249, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v - 2288) / 256, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v - 2288) % 256, 8)); |
| } else if (v <= 16777215) { |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, 250, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 0) & 0xff, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 8) & 0xff, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 16) & 0xff, 8)); |
| } else { |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, 251, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 0) & 0xff, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 8) & 0xff, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 16) & 0xff, 8)); |
| AVIF_CHECKRES(avifRWStreamWriteBits(stream, (v >> 24) & 0xff, 8)); |
| } |
| return AVIF_RESULT_OK; |
| } |