| // 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 <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->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) |
| { |
| stream->offset = offset; |
| if (stream->offset > stream->raw->size) { |
| stream->offset = stream->raw->size; |
| } |
| } |
| |
| avifBool avifROStreamSkip(avifROStream * stream, size_t byteCount) |
| { |
| 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) |
| { |
| 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) |
| { |
| 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) |
| { |
| 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) |
| { |
| 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) |
| { |
| 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) |
| { |
| 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) |
| { |
| AVIF_CHECK(avifROStreamRead(stream, (uint8_t *)v, sizeof(uint64_t))); |
| *v = avifNTOH64(*v); |
| return AVIF_TRUE; |
| } |
| |
| avifBool avifROStreamReadString(avifROStream * stream, char * output, size_t outputSize) |
| { |
| // 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 void 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; |
| } |
| if (stream->raw->size != newSize) { |
| avifRWDataRealloc(stream->raw, newSize); |
| } |
| } |
| |
| void avifRWStreamStart(avifRWStream * stream, avifRWData * raw) |
| { |
| stream->raw = raw; |
| stream->offset = 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); |
| } |
| } |
| } |
| |
| void avifRWStreamWrite(avifRWStream * stream, const void * data, size_t size) |
| { |
| if (!size) { |
| return; |
| } |
| |
| makeRoom(stream, size); |
| memcpy(stream->raw->data + stream->offset, data, size); |
| stream->offset += size; |
| } |
| |
| void avifRWStreamWriteChars(avifRWStream * stream, const char * chars, size_t size) |
| { |
| avifRWStreamWrite(stream, chars, size); |
| } |
| |
| avifBoxMarker avifRWStreamWriteFullBox(avifRWStream * stream, const char * type, size_t contentSize, int version, uint32_t flags) |
| { |
| avifBoxMarker marker = stream->offset; |
| size_t headerSize = sizeof(uint32_t) + 4 /* size of type */; |
| if (version != -1) { |
| headerSize += 4; |
| } |
| |
| 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 marker; |
| } |
| |
| avifBoxMarker avifRWStreamWriteBox(avifRWStream * stream, const char * type, size_t contentSize) |
| { |
| return avifRWStreamWriteFullBox(stream, type, contentSize, -1, 0); |
| } |
| |
| void avifRWStreamFinishBox(avifRWStream * stream, avifBoxMarker marker) |
| { |
| uint32_t noSize = avifHTONL((uint32_t)(stream->offset - marker)); |
| memcpy(stream->raw->data + marker, &noSize, sizeof(uint32_t)); |
| } |
| |
| void avifRWStreamWriteU8(avifRWStream * stream, uint8_t v) |
| { |
| makeRoom(stream, 1); |
| stream->raw->data[stream->offset] = v; |
| stream->offset += 1; |
| } |
| |
| void avifRWStreamWriteU16(avifRWStream * stream, uint16_t v) |
| { |
| size_t size = sizeof(uint16_t); |
| v = avifHTONS(v); |
| makeRoom(stream, size); |
| memcpy(stream->raw->data + stream->offset, &v, size); |
| stream->offset += size; |
| } |
| |
| void avifRWStreamWriteU32(avifRWStream * stream, uint32_t v) |
| { |
| size_t size = sizeof(uint32_t); |
| v = avifHTONL(v); |
| makeRoom(stream, size); |
| memcpy(stream->raw->data + stream->offset, &v, size); |
| stream->offset += size; |
| } |
| |
| void avifRWStreamWriteU64(avifRWStream * stream, uint64_t v) |
| { |
| size_t size = sizeof(uint64_t); |
| v = avifHTON64(v); |
| makeRoom(stream, size); |
| memcpy(stream->raw->data + stream->offset, &v, size); |
| stream->offset += size; |
| } |
| |
| void avifRWStreamWriteZeros(avifRWStream * stream, size_t byteCount) |
| { |
| makeRoom(stream, byteCount); |
| uint8_t * p = stream->raw->data + stream->offset; |
| uint8_t * end = p + byteCount; |
| while (p != end) { |
| *p = 0; |
| ++p; |
| } |
| stream->offset += byteCount; |
| } |