| // Copyright (c) 2010 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include <stdint.h> |
| #include <string.h> |
| |
| #include "bmpblk_header.h" |
| #include "bmpblk_font.h" |
| #include "image_types.h" |
| |
| /* BMP header, used to validate image requirements |
| * See http://en.wikipedia.org/wiki/BMP_file_format |
| */ |
| typedef struct { |
| uint8_t CharB; // must be 'B' |
| uint8_t CharM; // must be 'M' |
| uint32_t Size; |
| uint16_t Reserved[2]; |
| uint32_t ImageOffset; |
| uint32_t HeaderSize; |
| uint32_t PixelWidth; |
| uint32_t PixelHeight; |
| uint16_t Planes; // Must be 1 for x86 |
| uint16_t BitPerPixel; // 1, 4, 8, or 24 for x86 |
| uint32_t CompressionType; // 0 (none) for x86, 1 (RLE) for arm |
| uint32_t ImageSize; |
| uint32_t XPixelsPerMeter; |
| uint32_t YPixelsPerMeter; |
| uint32_t NumberOfColors; |
| uint32_t ImportantColors; |
| } __attribute__((packed)) BMP_IMAGE_HEADER; |
| |
| |
| ImageFormat identify_image_type(const void *buf, uint32_t bufsize, |
| ImageInfo *info) { |
| |
| if (info) |
| info->format = FORMAT_INVALID; |
| |
| if (bufsize < sizeof(BMP_IMAGE_HEADER) && |
| bufsize < sizeof(FontArrayHeader)) { |
| return FORMAT_INVALID; |
| } |
| |
| const BMP_IMAGE_HEADER *bhdr = buf; |
| if (bhdr->CharB == 'B' && bhdr->CharM == 'M' && |
| bhdr->Planes == 1 && |
| (bhdr->CompressionType == 0 || bhdr->CompressionType == 1) && |
| (bhdr->BitPerPixel == 1 || bhdr->BitPerPixel == 4 || |
| bhdr->BitPerPixel == 8 || bhdr->BitPerPixel == 24)) { |
| if (info) { |
| info->format = FORMAT_BMP; |
| info->width = bhdr->PixelWidth; |
| info->height = bhdr->PixelHeight; |
| } |
| return FORMAT_BMP; |
| } |
| |
| const FontArrayHeader *fhdr = buf; |
| if (0 == memcmp(&fhdr->signature, FONT_SIGNATURE, FONT_SIGNATURE_SIZE) && |
| fhdr->num_entries > 0) { |
| if (info) |
| info->format = FORMAT_FONT; |
| return FORMAT_FONT; |
| } |
| |
| return FORMAT_INVALID; |
| } |
| |
| |