--- /dev/null
+/* sfnt format font support for GNU Emacs.
+
+Copyright (C) 2023 Free Software Foundation, Inc.
+
+This file is part of GNU Emacs.
+
+GNU Emacs is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or (at
+your option) any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs. If not, write to the Free Software Foundation,
+Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#ifndef _SFNT_H_
+#define _SFNT_H_
+
+#include <stdint.h>
+#include <stddef.h>
+
+\f
+
+/* Container structure and enumerator definitions. */
+
+/* The sfnt container format is organized into different tables, such
+ as ``cmap'' or ``glyf''. Each of these tables has a specific
+ format and use. These are all the tables known to Emacs. */
+
+enum sfnt_table
+ {
+ SFNT_TABLE_CMAP,
+ SFNT_TABLE_GLYF,
+ SFNT_TABLE_HEAD,
+ SFNT_TABLE_HHEA,
+ SFNT_TABLE_HMTX,
+ SFNT_TABLE_LOCA,
+ SFNT_TABLE_MAXP,
+ SFNT_TABLE_NAME,
+ SFNT_TABLE_META,
+ };
+
+#define SFNT_ENDOF(type, field, type1) \
+ ((size_t) offsetof (type, field) + sizeof (type1))
+
+/* Each of these structures must be aligned so that no compiler will
+ ever generate padding bytes on platforms where the alignment
+ requirements for uint32_t and uint16_t are no larger than 4 and 2
+ bytes respectively. */
+
+struct sfnt_offset_subtable
+{
+ /* The scaler type. */
+ uint32_t scaler_type;
+
+ /* The number of tables. */
+ uint16_t num_tables;
+
+ /* (Maximum power of 2 <= numTables) * 16. */
+ uint16_t search_range;
+
+ /* log2 (maximum power of 2 <= numTables) */
+ uint16_t entry_selector;
+
+ /* numTables * 16 - searchRange. */
+ uint16_t range_shift;
+
+ /* Variable length data. */
+ struct sfnt_table_directory *subtables;
+};
+
+/* The table directory. Follows the offset subtable, with one for
+ each table. */
+
+struct sfnt_table_directory
+{
+ /* 4-byte identifier for each table. See sfnt_table_names. */
+ uint32_t tag;
+
+ /* Table checksum. */
+ uint32_t checksum;
+
+ /* Offset from the start of the file. */
+ uint32_t offset;
+
+ /* Length of the table in bytes, not subject to padding. */
+ uint32_t length;
+};
+
+enum sfnt_scaler_type
+ {
+ SFNT_SCALER_TRUE = 0x74727565,
+ SFNT_SCALER_VER1 = 0x00010000,
+ SFNT_SCALER_TYP1 = 0x74797031,
+ SFNT_SCALER_OTTO = 0x4F54544F,
+ };
+
+typedef int32_t sfnt_fixed;
+typedef int16_t sfnt_fword;
+typedef uint16_t sfnt_ufword;
+
+#define sfnt_coerce_fixed(fixed) ((sfnt_fixed) (fixed) / 65535.0)
+
+typedef unsigned int sfnt_glyph;
+typedef unsigned int sfnt_char;
+
+struct sfnt_head_table
+{
+ /* The version. This is a 16.16 fixed point number. */
+ sfnt_fixed version;
+
+ /* The revision. */
+ sfnt_fixed revision;
+
+ /* Checksum adjustment. */
+ uint32_t checksum_adjustment;
+
+ /* Magic number, should be 0x5F0F3CF5. */
+ uint32_t magic;
+
+ /* Flags for the font. */
+ uint16_t flags;
+
+ /* Units per em. */
+ uint16_t units_per_em;
+
+ /* Time of creation. */
+ uint32_t created_high, created_low;
+
+ /* Time of modification. */
+ uint32_t modified_high, modified_low;
+
+ /* Minimum bounds. */
+ sfnt_fword xmin, ymin, xmax, ymax;
+
+ /* Mac specific stuff. */
+ uint16_t mac_style;
+
+ /* Smallest readable size in pixels. */
+ uint16_t lowest_rec_ppem;
+
+ /* Font direction hint. */
+ int16_t font_direction_hint;
+
+ /* Index to loc format. 0 for short offsets, 1 for long. */
+ int16_t index_to_loc_format;
+
+ /* Unused. */
+ int16_t glyph_data_format;
+};
+
+struct sfnt_hhea_table
+{
+ /* The version. This is a 16.16 fixed point number. */
+ sfnt_fixed version;
+
+ /* The maximum ascent and descent values for this font. */
+ sfnt_fword ascent, descent;
+
+ /* The typographic line gap. */
+ sfnt_fword line_gap;
+
+ /* The maximum advance width. */
+ sfnt_ufword advance_width_max;
+
+ /* The minimum bearings on either side. */
+ sfnt_fword min_left_side_bearing, min_right_side_bearing;
+
+ /* The maximum extent. */
+ sfnt_fword x_max_extent;
+
+ /* Caret slope. */
+ int16_t caret_slope_rise, caret_slope_run;
+
+ /* Caret offset for non slanted fonts. */
+ sfnt_fword caret_offset;
+
+ /* Reserved values. */
+ int16_t reserved1, reserved2, reserved3, reserved4;
+
+ /* Should always be zero. */
+ int16_t metric_data_format;
+
+ /* Number of advanced widths in metrics table. */
+ uint16_t num_of_long_hor_metrics;
+};
+
+struct sfnt_cmap_table
+{
+ /* Should be zero. */
+ uint16_t version;
+
+ /* Number of subtables. */
+ uint16_t num_subtables;
+};
+
+enum sfnt_platform_id
+ {
+ SFNT_PLATFORM_UNICODE = 0,
+ SFNT_PLATFORM_MACINTOSH = 1,
+ SFNT_PLATFORM_RESERVED = 2,
+ SFNT_PLATFORM_MICROSOFT = 3,
+ };
+
+enum sfnt_unicode_platform_specific_id
+ {
+ SFNT_UNICODE_1_0 = 0,
+ SFNT_UNICODE_1_1 = 1,
+ SFNT_UNICODE_ISO_10646_1993 = 2,
+ SFNT_UNICODE_2_0_BMP = 3,
+ SFNT_UNICODE_2_0 = 4,
+ SFNT_UNICODE_VARIATION_SEQUENCES = 5,
+ SFNT_UNICODE_LAST_RESORT = 6,
+ };
+
+enum sfnt_macintosh_platform_specific_id
+ {
+ SFNT_MACINTOSH_ROMAN = 0,
+ SFNT_MACINTOSH_JAPANESE = 1,
+ SFNT_MACINTOSH_TRADITIONAL_CHINESE = 2,
+ SFNT_MACINTOSH_KOREAN = 3,
+ SFNT_MACINTOSH_ARABIC = 4,
+ SFNT_MACINTOSH_HEBREW = 5,
+ SFNT_MACINTOSH_GREEK = 6,
+ SFNT_MACINTOSH_RUSSIAN = 7,
+ SFNT_MACINTOSH_RSYMBOL = 8,
+ SFNT_MACINTOSH_DEVANGARI = 9,
+ SFNT_MACINTOSH_GURMUKHI = 10,
+ SFNT_MACINTOSH_GUJARATI = 11,
+ SFNT_MACINTOSH_ORIYA = 12,
+ SFNT_MACINTOSH_BENGALI = 13,
+ SFNT_MACINTOSH_TAMIL = 14,
+ SFNT_MACINTOSH_TELUGU = 15,
+ SFNT_MACINTOSH_KANNADA = 16,
+ SFNT_MACINTOSH_MALAYALAM = 17,
+ SFNT_MACINTOSH_SINHALESE = 18,
+ SFNT_MACINTOSH_BURMESE = 19,
+ SFNT_MACINTOSH_KHMER = 20,
+ SFNT_MACINTOSH_THAI = 21,
+ SFNT_MACINTOSH_LAOTIAN = 22,
+ SFNT_MACINTOSH_GEORGIAN = 23,
+ SFNT_MACINTOSH_ARMENIAN = 24,
+ SFNT_MACINTOSH_SIMPLIFIED_CHINESE = 25,
+ SFNT_MACINTOSH_TIBETIAN = 26,
+ SFNT_MACINTOSH_MONGOLIAN = 27,
+ SFNT_MACINTOSH_GEEZ = 28,
+ SFNT_MACINTOSH_SLAVIC = 29,
+ SFNT_MACINTOSH_VIETNAMESE = 30,
+ SFNT_MACINTOSH_SINDHI = 31,
+ SFNT_MACINTOSH_UNINTERPRETED = 32,
+ };
+
+enum sfnt_microsoft_platform_specific_id
+ {
+ SFNT_MICROSOFT_SYMBOL = 0,
+ SFNT_MICROSOFT_UNICODE_BMP = 1,
+ SFNT_MICROSOFT_SHIFT_JIS = 2,
+ SFNT_MICROSOFT_PRC = 3,
+ SFNT_MICROSOFT_BIG_FIVE = 4,
+ SFNT_MICROSOFT_WANSUNG = 5,
+ SFNT_MICROSOFT_JOHAB = 6,
+ SFNT_MICROSOFT_UNICODE_UCS_4 = 10,
+ };
+
+struct sfnt_cmap_encoding_subtable
+{
+ /* The platform ID. */
+ uint16_t platform_id;
+
+ /* Platform specific ID. */
+ uint16_t platform_specific_id;
+
+ /* Mapping table offset. */
+ uint32_t offset;
+};
+
+struct sfnt_cmap_encoding_subtable_data
+{
+ /* Format and possibly the length in bytes. */
+ uint16_t format, length;
+};
+
+struct sfnt_cmap_format_0
+{
+ /* Format, set to 0. */
+ uint16_t format;
+
+ /* Length in bytes. Should be 262. */
+ uint16_t length;
+
+ /* Language code. */
+ uint16_t language;
+
+ /* Character code to glyph index map. */
+ uint8_t glyph_index_array[256];
+};
+
+struct sfnt_cmap_format_2_subheader
+{
+ uint16_t first_code;
+ uint16_t entry_count;
+ int16_t id_delta;
+ uint16_t id_range_offset;
+};
+
+struct sfnt_cmap_format_2
+{
+ /* Format, set to 2. */
+ uint16_t format;
+
+ /* Length in bytes. */
+ uint16_t length;
+
+ /* Language code. */
+ uint16_t language;
+
+ /* Array mapping high bytes to subheaders. */
+ uint16_t sub_header_keys[256];
+
+ /* Variable length data. */
+ struct sfnt_cmap_format_2_subheader *subheaders;
+ uint16_t *glyph_index_array;
+ uint16_t num_glyphs;
+};
+
+struct sfnt_cmap_format_4
+{
+ /* Format, set to 4. */
+ uint16_t format;
+
+ /* Length in bytes. */
+ uint16_t length;
+
+ /* Language code. */
+ uint16_t language;
+
+ /* 2 * seg_count. */
+ uint16_t seg_count_x2;
+
+ /* 2 * (2**FLOOR(log2(segCount))) */
+ uint16_t search_range;
+
+ /* log2(searchRange/2) */
+ uint16_t entry_selector;
+
+ /* Variable-length data. */
+ uint16_t *end_code;
+ uint16_t *reserved_pad;
+ uint16_t *start_code;
+ int16_t *id_delta;
+ int16_t *id_range_offset;
+ uint16_t *glyph_index_array;
+
+ /* The number of elements in glyph_index_array. */
+ size_t glyph_index_size;
+};
+
+struct sfnt_cmap_format_6
+{
+ /* Format, set to 6. */
+ uint16_t format;
+
+ /* Length in bytes. */
+ uint16_t length;
+
+ /* Language code. */
+ uint16_t language;
+
+ /* First character code in subrange. */
+ uint16_t first_code;
+
+ /* Number of character codes. */
+ uint16_t entry_count;
+
+ /* Variable-length data. */
+ uint16_t *glyph_index_array;
+};
+
+struct sfnt_cmap_format_8_or_12_group
+{
+ uint32_t start_char_code;
+ uint32_t end_char_code;
+ uint32_t start_glyph_code;
+};
+
+struct sfnt_cmap_format_8
+{
+ /* Format, set to 8. */
+ uint16_t format;
+
+ /* Reserved. */
+ uint16_t reserved;
+
+ /* Length in bytes. */
+ uint32_t length;
+
+ /* Language code. */
+ uint32_t language;
+
+ /* Tightly packed array of bits (8K bytes total) indicating whether
+ the particular 16-bit (index) value is the start of a 32-bit
+ character code. */
+ uint8_t is32[65536];
+
+ /* Number of groups. */
+ uint32_t num_groups;
+
+ /* Variable length data. */
+ struct sfnt_cmap_format_8_or_12_group *groups;
+};
+
+/* cmap formats 10, 13 and 14 unsupported. */
+
+struct sfnt_cmap_format_12
+{
+ /* Format, set to 12. */
+ uint16_t format;
+
+ /* Reserved. */
+ uint16_t reserved;
+
+ /* Length in bytes. */
+ uint32_t length;
+
+ /* Language code. */
+ uint32_t language;
+
+ /* Number of groups. */
+ uint32_t num_groups;
+
+ /* Variable length data. */
+ struct sfnt_cmap_format_8_or_12_group *groups;
+};
+
+struct sfnt_maxp_table
+{
+ /* Table version. */
+ sfnt_fixed version;
+
+ /* The number of glyphs in this font - 1. Set at version 0.5 or
+ later. */
+ uint16_t num_glyphs;
+
+ /* These fields are only set in version 1.0 or later. Maximum
+ points in a non-composite glyph. */
+ uint16_t max_points;
+
+ /* Maximum contours in a non-composite glyph. */
+ uint16_t max_contours;
+
+ /* Maximum points in a composite glyph. */
+ uint16_t max_composite_points;
+
+ /* Maximum contours in a composite glyph. */
+ uint16_t max_composite_contours;
+
+ /* 1 if instructions do not use the twilight zone (Z0), or 2 if
+ instructions do use Z0; should be set to 2 in most cases. */
+ uint16_t max_zones;
+
+ /* Maximum points used in Z0. */
+ uint16_t max_twilight_points;
+
+ /* Number of Storage Area locations. */
+ uint16_t max_storage;
+
+ /* Number of FDEFs, equal to the highest function number + 1. */
+ uint16_t max_function_defs;
+
+ /* Number of IDEFs. */
+ uint16_t max_instruction_defs;
+
+ /* Maximum stack depth across Font Program ('fpgm' table), CVT
+ Program ('prep' table) and all glyph instructions (in the 'glyf'
+ table). */
+ uint16_t max_stack_elements;
+
+ /* Maximum byte count for glyph instructions. */
+ uint16_t max_size_of_instructions;
+
+ /* Maximum number of components referenced at ``top level'' for any
+ composite glyph. */
+ uint16_t max_component_elements;
+
+ /* Maximum levels of recursion; 1 for simple components. */
+ uint16_t max_component_depth;
+};
+
+struct sfnt_loca_table_short
+{
+ /* Offsets to glyph data divided by two. */
+ uint16_t *offsets;
+
+ /* Size of the offsets list. */
+ size_t num_offsets;
+};
+
+struct sfnt_loca_table_long
+{
+ /* Offsets to glyph data. */
+ uint32_t *offsets;
+
+ /* Size of the offsets list. */
+ size_t num_offsets;
+};
+
+struct sfnt_glyf_table
+{
+ /* Size of the glyph data. */
+ size_t size;
+
+ /* Pointer to possibly unaligned glyph data. */
+ unsigned char *glyphs;
+};
+
+struct sfnt_simple_glyph
+{
+ /* The total number of points in this glyph. */
+ size_t number_of_points;
+
+ /* Array containing the last points of each contour. */
+ uint16_t *end_pts_of_contours;
+
+ /* Total number of bytes needed for instructions. */
+ uint16_t instruction_length;
+
+ /* Instruction data. */
+ uint8_t *instructions;
+
+ /* Array of flags. */
+ uint8_t *flags;
+
+ /* Array of X coordinates. */
+ int16_t *x_coordinates;
+
+ /* Array of Y coordinates. */
+ int16_t *y_coordinates;
+
+ /* Pointer to the end of that array. */
+ int16_t *y_coordinates_end;
+};
+
+struct sfnt_compound_glyph_component
+{
+ /* Compound glyph flags. */
+ uint16_t flags;
+
+ /* Component glyph index. */
+ uint16_t glyph_index;
+
+ /* X-offset for component or point number; type depends on bits 0
+ and 1 in component flags. */
+ union {
+ uint8_t a;
+ int8_t b;
+ uint16_t c;
+ int16_t d;
+ } argument1;
+
+ /* Y-offset for component or point number; type depends on bits 0
+ and 1 in component flags. */
+ union {
+ uint8_t a;
+ int8_t b;
+ uint16_t c;
+ int16_t d;
+ } argument2;
+
+ /* Various scale formats. */
+ union {
+ uint16_t scale;
+ struct {
+ uint16_t xscale;
+ uint16_t yscale;
+ } a;
+ struct {
+ uint16_t xscale;
+ uint16_t scale01;
+ uint16_t scale10;
+ uint16_t yscale;
+ } b;
+ } u;
+};
+
+struct sfnt_compound_glyph
+{
+ /* Pointer to array of components. */
+ struct sfnt_compound_glyph_component *components;
+
+ /* Number of elements in that array. */
+ size_t num_components;
+
+ /* Instruction data. */
+ uint8_t *instructions;
+
+ /* Length of instructions. */
+ uint16_t instruction_length;
+};
+
+struct sfnt_glyph
+{
+ /* Number of contours in this glyph. */
+ int16_t number_of_contours;
+
+ /* Coordinate bounds. */
+ sfnt_fword xmin, ymin, xmax, ymax;
+
+ /* Either a simple glyph or a compound glyph, depending on which is
+ set. */
+ struct sfnt_simple_glyph *simple;
+ struct sfnt_compound_glyph *compound;
+};
+
+\f
+
+/* Glyph outline decomposition. */
+
+struct sfnt_point
+{
+ /* X and Y in em space. */
+ sfnt_fixed x, y;
+};
+
+typedef void (*sfnt_move_to_proc) (struct sfnt_point, void *);
+typedef void (*sfnt_line_to_proc) (struct sfnt_point, void *);
+typedef void (*sfnt_curve_to_proc) (struct sfnt_point,
+ struct sfnt_point,
+ void *);
+
+typedef struct sfnt_glyph *(*sfnt_get_glyph_proc) (sfnt_glyph, void *,
+ bool *);
+typedef void (*sfnt_free_glyph_proc) (struct sfnt_glyph *, void *);
+
+\f
+
+/* Decomposed glyph outline. */
+
+struct sfnt_glyph_outline_command
+{
+ /* Flags for this outline command. */
+ int flags;
+
+ /* X and Y position of this command. */
+ sfnt_fixed x, y;
+};
+
+/* Structure describing a single recorded outline in fixed pixel
+ space. */
+
+struct sfnt_glyph_outline
+{
+ /* Array of outlines elements. */
+ struct sfnt_glyph_outline_command *outline;
+
+ /* Size of the outline data, and how much is full. */
+ size_t outline_size, outline_used;
+
+ /* Rectangle defining bounds of the outline. Namely, the minimum
+ and maximum X and Y positions. */
+ sfnt_fixed xmin, ymin, xmax, ymax;
+};
+
+enum sfnt_glyph_outline_flags
+ {
+ SFNT_GLYPH_OUTLINE_LINETO = (1 << 1),
+ };
+
+struct sfnt_build_glyph_outline_context
+{
+ /* The outline being built. */
+ struct sfnt_glyph_outline *outline;
+
+ /* The head table. */
+ struct sfnt_head_table *head;
+
+ /* The pixel size being used, and any extra flags to apply to the
+ outline at this point. */
+ int pixel_size;
+
+ /* Factor to multiply positions by to get the pixel width. */
+ double factor;
+
+ /* The position of the pen in 16.16 fixed point format. */
+ sfnt_fixed x, y;
+};
+
+\f
+
+/* Glyph rasterization. */
+
+struct sfnt_raster
+{
+ /* Basic dimensions of the raster. */
+ unsigned short width, height;
+
+ /* Integer offset to apply to positions in the raster. */
+ unsigned short offx, offy;
+
+ /* Pointer to coverage data. */
+ unsigned char *cells;
+};
+
+struct sfnt_edge
+{
+ /* Next edge in this chain. */
+ struct sfnt_edge *next;
+
+ /* Winding direction. 1 if clockwise, -1 if counterclockwise. */
+ int winding;
+
+ /* X position, top and bottom of edges. */
+ sfnt_fixed x, top, bottom;
+
+ /* step_x is how many pixels to move for each increase in Y. */
+ sfnt_fixed step_x;
+};
+
+\f
+
+/* Polygon rasterization constants. */
+
+enum
+ {
+ SFNT_POLY_SHIFT = 2,
+ SFNT_POLY_SAMPLE = (1 << SFNT_POLY_SHIFT),
+ SFNT_POLY_MASK = (SFNT_POLY_SAMPLE - 1),
+ SFNT_POLY_STEP = (0x10000 >> SFNT_POLY_SHIFT),
+ SFNT_POLY_START = (SFNT_POLY_STEP >> 1),
+ };
+
+\f
+
+/* Glyph metrics computation. */
+
+struct sfnt_long_hor_metric
+{
+ uint16_t advance_width;
+ int16_t left_side_bearing;
+};
+
+struct sfnt_hmtx_table
+{
+ /* Array of horizontal metrics for each glyph. */
+ struct sfnt_long_hor_metric *h_metrics;
+
+ /* Lbearing for remaining glyphs. */
+ int16_t *left_side_bearing;
+};
+
+/* Structure describing the metrics of a single glyph. The fields
+ mean the same as in XCharStruct, except they are 16.16 fixed point
+ values, and are missing significant information. */
+
+struct sfnt_glyph_metrics
+{
+ /* Distance between origin and left edge of raster. Positive
+ changes move rightwards. */
+ sfnt_fixed lbearing;
+
+ /* Advance to next glyph's origin. */
+ sfnt_fixed advance;
+};
+
+\f
+
+/* Font style parsing. */
+
+struct sfnt_name_record
+{
+ /* Platform identifier code. */
+ uint16_t platform_id;
+
+ /* Platform specific ID. */
+ uint16_t platform_specific_id;
+
+ /* Language identifier. */
+ uint16_t language_id;
+
+ /* Name identifier. */
+ uint16_t name_id;
+
+ /* String length in bytes. */
+ uint16_t length;
+
+ /* Offset from start of storage area. */
+ uint16_t offset;
+};
+
+struct sfnt_name_table
+{
+ /* Format selector of name table. */
+ uint16_t format;
+
+ /* Number of name records. */
+ uint16_t count;
+
+ /* Offset to start of string data. */
+ uint16_t string_offset;
+
+ /* Variable length data. */
+ struct sfnt_name_record *name_records;
+
+ /* Start of string data. */
+ unsigned char *data;
+};
+
+/* Name identifier codes. These are Apple's codes, not
+ Microsoft's. */
+
+enum sfnt_name_identifier_code
+ {
+ SFNT_NAME_COPYRIGHT_NOTICE = 0,
+ SFNT_NAME_FONT_FAMILY = 1,
+ SFNT_NAME_FONT_SUBFAMILY = 2,
+ SFNT_NAME_UNIQUE_SUBFAMILY_IDENTIFICATION = 3,
+ SFNT_NAME_FULL_NAME = 4,
+ SFNT_NAME_NAME_TABLE_VERSION = 5,
+ SFNT_NAME_POSTSCRIPT_NAME = 6,
+ SFNT_NAME_TRADEMARK_NOTICE = 7,
+ SFNT_NAME_MANUFACTURER_NAME = 8,
+ SFNT_NAME_DESIGNER = 9,
+ SFNT_NAME_DESCRIPTION = 10,
+ SFNT_NAME_FONT_VENDOR_URL = 11,
+ SFNT_NAME_FONT_DESIGNER_URL = 12,
+ SFNT_NAME_LICENSE_DESCRIPTION = 13,
+ SFNT_NAME_LICENSE_INFORMATION_URL = 14,
+ SFNT_NAME_PREFERRED_FAMILY = 16,
+ SFNT_NAME_PREFERRED_SUBFAMILY = 17,
+ SFNT_NAME_COMPATIBLE_FULL = 18,
+ SFNT_NAME_SAMPLE_TEXT = 19,
+ SFNT_NAME_VARIATIONS_POSTSCRIPT_NAME_PREFIX = 25,
+ };
+
+struct sfnt_meta_data_map
+{
+ /* Identifier for the tag. */
+ uint32_t tag;
+
+ /* Offset from start of table to data. */
+ uint32_t data_offset;
+
+ /* Length of the data. */
+ uint32_t data_length;
+};
+
+struct sfnt_meta_table
+{
+ /* Version of the table. Currently set to 1. */
+ uint32_t version;
+
+ /* Flags. Currently 0. */
+ uint32_t flags;
+
+ /* Offset from start of table to beginning of variable length
+ data. */
+ uint32_t data_offset;
+
+ /* Number of data maps in the table. */
+ uint32_t num_data_maps;
+
+ /* Beginning of variable length data. */
+ struct sfnt_meta_data_map *data_maps;
+
+ /* The whole table contents. */
+ unsigned char *data;
+};
+
+enum sfnt_meta_data_tag
+ {
+ SFNT_META_DATA_TAG_DLNG = 0x646c6e67,
+ SFNT_META_DATA_TAG_SLNG = 0x736c6e67,
+ };
+
+\f
+
+/* Function declarations. Keep these sorted by the order in which
+ they appear in sfnt.c. Keep each line no longer than 80
+ columns. */
+
+#ifndef TEST
+
+extern struct sfnt_offset_subtable *sfnt_read_table_directory (int);
+
+#define PROTOTYPE \
+ int, struct sfnt_offset_subtable *, \
+ struct sfnt_cmap_encoding_subtable **, \
+ struct sfnt_cmap_encoding_subtable_data ***
+static struct sfnt_cmap_table *sfnt_read_cmap_table (PROTOTYPE);
+#undef PROTOTYPE
+
+#define PROTOTYPE int, struct sfnt_offset_subtable *
+extern struct sfnt_head_table *sfnt_read_head_table (PROTOTYPE);
+extern struct sfnt_hhea_table *sfnt_read_hhea_table (PROTOTYPE);
+extern struct sfnt_loca_table_short *sfnt_read_loca_table_short (PROTOTYPE);
+extern struct sfnt_loca_table_long *sfnt_read_loca_table_long (PROTOTYPE);
+extern struct sfnt_maxp_table *sfnt_read_maxp_table (PROTOTYPE);
+extern struct sfnt_glyf_table *sfnt_read_glyf_table (PROTOTYPE);
+#undef PROTOTYPE
+
+extern struct sfnt_glyph *sfnt_read_glyph (sfnt_glyph, struct sfnt_glyf_table *,
+ struct sfnt_loca_table_short *,
+ struct sfnt_loca_table_long *);
+
+#define PROTOTYPE \
+ struct sfnt_glyph *, \
+ struct sfnt_head_table *, \
+ int, sfnt_get_glyph_proc, \
+ sfnt_free_glyph_proc, \
+ void *
+extern struct sfnt_glyph_outline *sfnt_build_glyph_outline (PROTOTYPE);
+#undef PROTOTYPE
+
+extern void sfnt_prepare_raster (struct sfnt_raster *,
+ struct sfnt_glyph_outline *);
+
+#define PROTOTYPE struct sfnt_glyph_outline *
+extern struct sfnt_raster *sfnt_raster_glyph_outline (PROTOTYPE);
+#undef PROTOTYPE
+
+#define PROTOTYPE \
+ int, \
+ struct sfnt_offset_subtable *, \
+ struct sfnt_hhea_table *, \
+ struct sfnt_maxp_table *
+extern struct sfnt_hmtx_table *sfnt_read_hmtx_table (PROTOTYPE);
+#undef PROTOTYPE
+
+extern int sfnt_lookup_glyph_metrics (sfnt_glyph, int,
+ struct sfnt_glyph_metrics *,
+ struct sfnt_hmtx_table *,
+ struct sfnt_hhea_table *,
+ struct sfnt_head_table *,
+ struct sfnt_maxp_table *);
+
+#define PROTOTYPE int, struct sfnt_offset_subtable *
+extern struct sfnt_name_table *sfnt_read_name_table (PROTOTYPE);
+#undef PROTOTYPE
+
+extern unsigned char *sfnt_find_name (struct sfnt_name_table *,
+ enum sfnt_name_identifier_code,
+ struct sfnt_name_record *);
+
+#define PROTOTYPE int, struct sfnt_offset_subtable *
+extern struct sfnt_meta_table *sfnt_read_meta_table (PROTOTYPE);
+#undef PROTOTYPE
+
+extern char *sfnt_find_metadata (struct sfnt_meta_table *,
+ enum sfnt_meta_data_tag,
+ struct sfnt_meta_data_map *);
+
+#endif /* TEST */
+#endif /* _SFNT_H_ */
--- /dev/null
+/* sfnt format font driver for GNU Emacs.
+
+Copyright (C) 2023 Free Software Foundation, Inc.
+
+This file is part of GNU Emacs.
+
+GNU Emacs is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or (at
+your option) any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs. If not, write to the Free Software Foundation,
+Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#include <config.h>
+
+#include "lisp.h"
+#include "sfnt.h"
+#include "coding.h"
+
+/* Generic font driver for sfnt-based fonts (currently TrueType, but
+ it would be easy to add CFF support in the future.)
+
+ This is not a complete font driver. Hooks must be supplied by the
+ platform implementer to draw glyphs. */
+
+\f
+
+/* Description of a font that hasn't been opened. */
+
+struct sfnt_font_desc
+{
+ /* Next font in this list. */
+ struct sfnt_font_desc *next;
+
+ /* Family name of the font. */
+ Lisp_Object family;
+
+ /* Style name of the font. */
+ Lisp_Object style;
+
+ /* Numeric width, weight, slant and spacing. */
+ int width, weight, slant, spacing;
+
+ /* Path to the font file. */
+ char *path;
+};
+
+/* List of fonts. */
+
+static struct sfnt_font_desc *system_fonts;
+
+/* Font enumeration and matching. The sfnt driver assumes it can read
+ data from each font at startup. It then reads the head, meta and
+ name tables to determine font data, and records the font in a list
+ of system fonts that is then matched against. */
+
+/* Set up the coding system CODING to decode string data from the
+ given platform id ID and platform specific id PLATFORM_SPECIFIC_ID.
+ Value is 0 upon success, 1 upon failure. */
+
+static int
+sfnt_setup_coding_system (enum sfnt_platform_id id, int platform_specific_id,
+ struct coding_system *coding)
+{
+ Lisp_Object system;
+
+ system = Qnil;
+
+ /* Figure out what coding system to use. */
+
+ switch (id)
+ {
+ case SFNT_PLATFORM_UNICODE:
+ system = Qutf_16be;
+ break;
+
+ case SFNT_PLATFORM_MACINTOSH:
+
+ if (platform_specific_id == SFNT_MACINTOSH_ROMAN)
+ system = Qmac_roman;
+ else
+ /* MULE doesn't support the rest... */
+ system = Qnil;
+
+ break;
+
+ case SFNT_PLATFORM_MICROSOFT:
+ system = Qutf_16be;
+
+ /* FIXME will someone look at the MS spec and see if this
+ right. */
+ if (platform_specific_id
+ == SFNT_MICROSOFT_BIG_FIVE)
+ system = Qchinese_big5;
+
+ break;
+ }
+
+ if (NILP (system))
+ return 1;
+
+ setup_coding_system (system, coding);
+}
+
+/* Globals used to communicate inside the condition-case wrapper. */
+static struct coding_system *sfnt_font_coding;
+
+/* The src_object being encoded from. This should be on the stack as
+ well, or it will get garbage collected. */
+static Lisp_Object sfnt_font_src_object;
+
+/* From-position. */
+static ptrdiff_t sfnt_font_from, sfnt_font_from_byte;
+
+/* To-position. */
+static ptrdiff_t sfnt_font_to, sfnt_font_to_byte;
+
+/* Destination object. Once again, this should also be on the
+ stack. */
+static Lisp_Object sfnt_font_dst_object;
+
+/* Error flag. Set to true if a signal was caught. */
+static bool sfnt_font_signal;
+
+static Lisp_Object
+sfnt_safe_encode_coding_object_1 (void)
+{
+ encode_coding_object (sfnt_font_coding,
+ sfnt_font_src_object,
+ sfnt_font_from,
+ sfnt_font_from_byte,
+ sfnt_font_to,
+ sfnt_font_to_byte,
+ sfnt_font_dst_object);
+ return Qnil;
+}
+
+static Lisp_Object
+sfnt_safe_encode_coding_object_2 (void)
+{
+ sfnt_font_signal = true;
+
+ return Qnil;
+}
+
+/* Like encode_coding_object, but return 1 if a signal happens. Value
+ is otherwise 0. */
+
+static int
+sfnt_safe_encode_coding_object (struct coding_system *coding,
+ Lisp_Object src_object,
+ ptrdiff_t from, ptrdiff_t from_byte,
+ ptrdiff_t to, ptrdiff_t to_byte,
+ Lisp_Object dst_object)
+{
+ sfnt_font_coding = coding;
+ sfnt_font_src_object = src_object;
+ sfnt_font_from = from;
+ sfnt_font_from_byte = from_byte;
+ sfnt_font_to = to;
+ sfnt_font_to_byte = to_byte;
+ sfnt_font_dst_object = dst_object;
+ sfnt_font_signal = false;
+
+ internal_condition_case (sfnt_safe_encode_coding_object_1,
+ Qt,
+ sfnt_safe_encode_coding_object_2);
+
+ return (int) sfnt_font_signal;
+}
+
+/* Decode the specified string DATA. The encoding is determined based
+ on PLATFORM_ID, PLATFORM_SPECIFIC_ID and LANGUAGE_ID. Consult
+ sfnt.h and the TrueType Reference Manual for more details. LENGTH
+ is the length of DATA in bytes.
+
+ Value is nil upon failure, else the decoded string. */
+
+static Lisp_Object
+sfnt_decode_font_string (unsigned char *data, enum sfnt_platform_id id,
+ int platform_specific_id, int language_id,
+ size_t length)
+{
+ struct coding_system coding;
+
+ memset (&coding, 0, sizeof coding);
+ sfnt_setup_coding_system (id, platform_specific_id, &coding);
+ coding.mode |= CODING_MODE_SAFE_ENCODING;
+ coding.mode |= CODING_MODE_LAST_BLOCK;
+ /* Suppress producing escape sequences for composition. */
+ coding.common_flags &= ~CODING_ANNOTATION_MASK;
+ coding.source = data;
+
+ if (sfnt_safe_encode_coding_object (&coding, Qnil, 0, 0,
+ 0, 0, length, length,
+ Qnil))
+ return Qnil;
+
+ return coding.dst_object;
+}
+
+/* Decode the family and style names from the name table NAME. Return
+ 0 and the family and style names upon success, else 1. */
+
+static int
+sfnt_decode_family_style (struct sfnt_name_table *name,
+ Lisp_Object *family, Lisp_Object *style)
+{
+ struct sfnt_name_record family_rec, style_rec;
+ unsigned char *family_data, *style_data;
+
+ family_data = sfnt_find_name (name, SFNT_NAME_FONT_FAMILY,
+ &family_rec);
+ style_data = sfnt_find_name (name, SFNT_NAME_FONT_SUBFAMILY,
+ &style_rec);
+
+ if (!family_data || !style_data)
+ return 1;
+
+ /* Now decode the data. */
+ *family = sfnt_decode_font_string (family_data,
+ family_rec.platform_id,
+ family_rec.platform_specific_id,
+ family_rec.language_id,
+ family_rec.length);
+ *style = sfnt_decode_font_string (style_data,
+ style_rec.platform_id,
+ style_rec.platform_specific_id,
+ style_rec.language_id,
+ style_rec.length);
+
+ /* Return whether or not it was successful. */
+ return (!NILP (*family) && !NILP (*style)) ? 0 : 1;
+}
+
+struct sfnt_style_desc
+{
+ /* The C string to match against. */
+ const char *c_string;
+
+ /* The value of the style field. */
+ int value;
+};
+
+/* Array of style descriptions describing weight. */
+static struct sfnt_style_desc sfnt_weight_descriptions =
+ {
+ { "thin", 0, },
+ { "extralight", 40, },
+ { "ultralight", 40, },
+ { "demilight", 55, },
+ { "semilight", 55, },
+ { "book", 75, },
+ { "medium", 100, },
+ { "demibold", 180, },
+ { "semibold", 180, },
+ { "bold", 200, },
+ { "extrabold", 205, },
+ { "ultrabold", 205, },
+ { "black", 210, },
+ { "heavy", 210, },
+ { "extrablack", 215, },
+ { "ultrablack", 215, },
+ };
+
+/* Array of style descriptions describing slant. */
+static struct sfnt_style_desc sfnt_slant_descriptions =
+ {
+ { "italic", 100, },
+ { "oblique", 110, },
+ };
+
+/* Array of style descriptions describing width. */
+static struct sfnt_width_desc sfnt_width_descriptions =
+ {
+ { "ultracondensed", 50, },
+ { "extracondensed", 63, },
+ { "condensed", 75, },
+ { "semicondensed", 87, },
+ { "semiexpanded", 113, },
+ { "expanded", 125, },
+ { "extraexpanded", 150, },
+ { "ultraexpanded", 200, },
+ };
+
+/* Figure out DESC->width, DESC->weight, DESC->slant and DESC->spacing
+ based on the style name passed as STYLE. */
+
+static void
+sfnt_parse_style (Lisp_Object style, struct sfnt_font_desc *desc)
+{
+ char *style, single, *saveptr;
+ int i;
+
+ /* Fill in default values. */
+ desc->weight = 80;
+ desc->slant = 0;
+ desc->width = 100;
+
+ /* Split the style into spaces. As long as no weight, slant, or
+ width is encountered, look in the corresponding descriptions
+ array. GC must not happen inside this block. */
+ style = SSDATA (Fdowncase (style));
+ saveptr = NULL;
+
+ while ((single = strtok_r (style, " ", &saveptr)))
+ {
+ style = NULL;
+
+ if (desc->weight == 80)
+ {
+ /* Weight hasn't been found yet. Scan through the weight
+ table. */
+ for (i = 0; i < ARRAYELTS (sfnt_weight_descriptions); ++i)
+ {
+ if (!strcmp (sfnt_weight_descriptions[i].c_string,
+ single))
+ {
+ /* Weight found. Continue on reading the slant and
+ width. */
+ desc->weight = sfnt_weight_descriptions[i].value;
+ goto next;
+ }
+ }
+ }
+
+ if (!desc->slant)
+ {
+ /* Slant hasn't been found yet. Scan through the slant
+ table. */
+ for (i = 0; i < ARRAYELTS (sfnt_slant_descriptions); ++i)
+ {
+ if (!strcmp (sfnt_weight_descriptions[i].c_string,
+ single))
+ {
+ /* Slant found. Continue on reading the weight and
+ width. */
+ desc->slant = sfnt_weight_descriptions[i].value;
+ goto next;
+ }
+ }
+ }
+
+ if (desc->width == 100)
+ {
+ /* Width hasn't been found yet. Scan through the width
+ table. */
+ for (i = 0; i < ARRAYELTS (sfnt_width_descriptions); ++i)
+ {
+ if (!strcmp (sfnt_width_descriptions[i].c_string,
+ single))
+ {
+ /* Width found. Continue on reading the slant and
+ weight. */
+ desc->slant = sfnt_width_descriptions[i].value;
+ goto next;
+ }
+ }
+ }
+
+ next:
+
+ /* Break early if everything has been found. */
+ if (desc->slant && desc->width != 100 && desc->weight != 80)
+ break;
+
+ continue;
+ }
+}
+
+/* Enumerate the font FILE into the list of system fonts. Return 1 if
+ it could not be enumerated, 0 otherwise. */
+
+int
+sfnt_enum_font (const char *file)
+{
+ struct sfnt_font_desc *desc;
+ int fd;
+ struct sfnt_offset_subtable *subtables;
+ struct sfnt_head_table *head;
+ struct sfnt_name_table *name;
+ struct sfnt_meta_table *meta;
+ Lisp_Object family, style;
+
+ /* Create the font desc and copy in the file name. */
+ desc = xzalloc (sizeof *desc + strlen (file) + 1);
+ desc->path = (char *) (desc + 1);
+ memcpy (desc->path, file, strlen (file) + 1);
+
+ /* Now open the font for reading. */
+ fd = emacs_open (file, O_RDWR);
+
+ /* Read the table directory. */
+ subtables = sfnt_read_table_directory (fd);
+
+ if (!subtables)
+ goto bail0;
+
+ /* Check that this is a TrueType font. */
+ if (subtables->scaler_type != SFNT_SCALER_TRUE
+ && subtables->scaler_type != SFNT_SCALER_VER1)
+ goto bail1;
+
+ /* Read required tables. */
+ head = sfnt_read_head_table (fd, subtables);
+ if (!head)
+ goto bail1;
+
+ name = sfnt_read_name_table (fd, subtables);
+ if (!name)
+ goto bail2;
+
+ /* meta is not required, nor present on many non-Apple fonts. */
+ meta = sfnt_read_meta_table (fd, subtables);
+
+ /* Decode the family and style from the name table. */
+ if (sfnt_decode_family_style (name, &family, &style))
+ goto bail3;
+
+ /* Set the family. */
+ desc->family = family;
+
+ /* Parse the style. */
+ sfnt_parse_style (style, desc);
+
+ /* Figure out the spacing. Some fancy test like what Fontconfig
+ does is probably in order but not really necessary. */
+ if (!NILP (Fstring_search (Fdowncase (family),
+ build_string ("mono"),
+ Qnil)))
+ desc->spacing = 100; /* FC_MONO */
+
+ /* Finally add mac-style flags. Allow them to override styles that
+ have not been found. */
+
+ if (head->mac_style & 01 && desc->weight == 80) /* Bold */
+ desc->weight = 200;
+
+ if (head->mac_style & 02 && desc->slant == 0) /* Italic */
+ desc->slant = 100;
+
+ /* Set the style, link the desc onto system_fonts and return. */
+ desc->style = style;
+ desc->next = system_fonts;
+ system_fonts = desc;
+
+ xfree (meta);
+ xfree (name);
+ xfree (head);
+ xfree (subtables);
+ emacs_close (fd);
+ return 0;
+
+ bail3:
+ xfree (meta);
+ xfree (name);
+ bail2:
+ xfree (head);
+ bail1:
+ xfree (subtables);
+ bail0:
+ emacs_close (fd);
+ return 1;
+}
+
+\f
+
+void
+syms_of_sfntfont (void)
+{
+ DEFSYM (Qutf_16be, "utf-16be");
+ DEFSYM (Qmac_roman, "mac-roman");
+}
+
+void
+mark_sfntfont (void)
+{
+ struct sfnt_font_desc *desc;
+
+ /* Mark each font desc. */
+ for (desc = system_fonts; ++desc; desc = desc->next)
+ {
+ mark_object (desc->family);
+ mark_object (desc->style);
+ }
+}
projects / emacs.git / commitdiff