First botched attempt at reading image data :D

src/tiff/tiffread.h

@@ -0,0 +1,109 @@
+#ifndef TIFFREAD_H
+#define TIFFREAD_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+#include "aliases.h"
+#include "image.h"
+
+#define TAG_MAX_COUNT (UINT16_MAX * sizeof(const char *))
+// Technically, the type parameter is 2-bytes long, but there aren't so many
+// types specified in the spec, so UINT8_MAX should be sufficient
+#define TYPE_MAX_COUNT (UINT8_MAX * sizeof(const char *))
+
+// clang-format off
+enum tiff_byte_order {
+  TIFF_ORDER_LITTLE_ENDIAN = 0x4949,
+  TIFF_ORDER_BIG_ENDIAN    = 0x4d4d,
+};
+// clang-format on
+
+typedef struct hdr TiffHdr;
+struct hdr {
+  u16 order;
+  u16 magic;
+  u32 first_ifd_offset;
+};
+
+// clang-format off
+enum tiff_public_tags {
+  #include "tiff_public_tags.inc"
+};
+
+internal const char *tag_names[TAG_MAX_COUNT] = {
+  #define TIFF_TAG_LOOKUP
+  #include "tiff_public_tags.inc"
+  #undef TIFF_TAG_LOOKUP
+};
+
+enum tiff_field_types {
+  #include "tiff_field_types.inc"
+};
+
+typedef struct field_type TiffFieldType;
+struct field_type {
+  const char *name;
+  u16 byte_count;
+};
+
+internal TiffFieldType field_types[TYPE_MAX_COUNT] = {
+  #define TIFF_TYPE_LOOKUP
+  #include "tiff_field_types.inc"
+  #undef TIFF_TYPE_LOOKUP
+};
+// clang-format on
+
+typedef struct field TiffField;
+struct field {
+  u16 tag;
+  u16 type;
+  u32 count;
+  u32 value_offset;
+};
+
+typedef struct IFD TiffIFD;
+struct IFD {
+  u16 count;
+  TiffField *fields;
+  u32 next_ifd;
+};
+
+// clang-format off
+enum tiff_compression {
+  TIFF_COMPRESSION_UNCOMPRESSED = 0x0001,
+  TIFF_COMPRESSION_CCITT_1D     = 0x0002,
+  TIFF_COMPRESSION_GROUP_3_FAX  = 0x0003,
+  TIFF_COMPRESSION_GROUP_4_FAX  = 0x0004,
+  TIFF_COMPRESSION_LZW          = 0x0005,
+  TIFF_COMPRESSION_JPEG         = 0x0006,
+  TIFF_COMPRESSION_PACK_BITS    = 0x8005,
+};
+
+enum tiff_photometric_interpretation {
+  TIFF_PHOTOMETRIC_INTERPRETATION_WHITE_IS_ZERO     = 0x0000,
+  TIFF_PHOTOMETRIC_INTERPRETATION_BLACK_IS_ZERO     = 0x0001,
+  TIFF_PHOTOMETRIC_INTERPRETATION_RGB               = 0x0002,
+  TIFF_PHOTOMETRIC_INTERPRETATION_RGB_PALETTE       = 0x0003,
+  TIFF_PHOTOMETRIC_INTERPRETATION_TRANSPARENCY_MASK = 0x0004,
+  TIFF_PHOTOMETRIC_INTERPRETATION_CMYK              = 0x0005,
+  TIFF_PHOTOMETRIC_INTERPRETATION_YCbCr             = 0x0006,
+  TIFF_PHOTOMETRIC_INTERPRETATION_CIELab            = 0x0008,
+
+  TIFF_PHOTOMETRIC_INTERPRETATION_INVALID,
+};
+
+enum tiff_planar_configuration {
+  TIFF_PLANAR_CONFIG_CHUNKY = 0x0001,
+  TIFF_PLANAR_CONFIG_PLANAR = 0x0002,
+};
+// clang-format on
+
+Image *read_baseline_tiff(const char *file, const Allocator *allocator);
+
+#ifdef __cplusplus
+}
+#endif // __cplusplus
+
+#endif // !TIFFREAD_H